L-tryptophan ingestion does not induce progressive systemic sclerosis (scleroderma). A retrospective analysis of 153 patients suffering from progressive systemic sclerosis failed to show any correlation between either onset or worsening of the disease and L-tryptophan ingestion. Only one woman developed typical acrosclerosis without signs of the eosinophilia-myalgia syndrome during exposure to the drug.


Staphylococcus aureus leukocidin: a new virulence factor in cutaneous infections? An epidemiological and experimental study. Panton-Valentine leukocidin (PVL) is a Staphylococcus aureus (SA) exotoxin, which kills human granulocytes and monocytes in vitro. Among 43 SA strains from cutaneous infections, 12 were PVL producers, whereas among 49 blood culture strains, only 1 produced PVL. Most PVL-producing strains (11/22) came from 22 primitive cutaneous infections, especially furuncles and abscesses, while only 1 PVL-producing strain came from 21 secondary infections of dermatoses such as bullous or pruritic diseases. Intradermal injections of PVL in rabbits induced edema, erythema and necrosis; histopathological changes at the injection sites consisted mainly in leukocytoclasis and vascular necrosis. All changes were dose dependent, and previous immunization of rabbits partially neutralized PVL-induced effects. Production of PVL in vivo after injections of bacteria seems to be low, and the histopathological lesions induced in the rabbit skin do not appear to be specifically related to PVL activity. However, PVL is a good candidate as a new virulence factor in cutaneous SA infections.


Extensive variant of cutaneous amyloidosis: report of a case with electron-microscopic and immunohistochemical studies of the basement membrane zone at sites of amyloid production. A 60-year-old Japanese female developed widespread lichenoid eruptions with pigmentation, which initially appeared in preceding erythematous skin lesions due to dermatomyositis. Thioflavine T and Dylon stainings, electron microscopy and immunohistochemistry revealed that thick amyloid deposits were present in the papillary dermis particularly beneath the epidermis. Autopsy showed no evidence of systemic amyloidosis. Electron microscopy of the lesional skin disclosed the disturbance of lamina densa formation in the epidermal basement membrane zone (BMZ). There was disruption and dissociation of the lamina densa from the basal cell, and a lamina-densa-like substance was found in the amyloid deposits. Immunofluorescence and immunoelectron microscopy showed that type IV and VII collagens, LDA-1 antigen (a noncollagenous component of the BMZ) and laminin were distributed in irregular thick deposits along the BMZ and were also present within the amyloid itself. These findings indicate that morphological and immunohistochemical abnormalities of the lamina densa may be involved in amyloid production at the interface of the epidermis and dermis, at least in this case.


Derivation of a dysplasia index for epidermal neoplasia. Measurements have been performed on histological sections of normal, paralesional and affected skin of patients with solar keratoses in an attempt at quantification of the degree of dysplasia. Features of dysplasia, including the epidermal thickness, the nuclear fraction and nuclear size distribution and shape, have been individually derived and incorporated into a formula designed to reflect the degree of dysplastic change within the epidermis. Application of this 'index of dysplasia' has been shown to differentiate lesional epidermis from that of the surrounding and normal non-sun-exposed skin. In addition, this index correlated well with independent dermatopathologists' assessments of the degree of dysplasia.


Progressive facial hemiatrophy: report of five cases and biochemical analysis of connective tissue. Five cases of progressive facial hemiatrophy (PFH) are reported. A nonindurated depression on normal-colored skin was observed in the cheeks of 3 subjects, and 2 patients showed indurated, pigmented atrophic lesions associated with linear scleroderma or generalized morphea. Lipoatrophy with mild subcutaneous fibrosis was observed histologically in the patients with nonindurated depressions. In contrast, the patients with indurated lesions exhibited a marked dermal fibrosis and the disappearance of appendices in the dermis. When compared with unaffected skin used as a control, collagen and glycosaminoglycan contents were not different in diseased areas. However, the dermatan sulfate/hyaluronic acid ratio was increased 1.5- to 3.2-fold in PFH patients regardless of their clinical and histological differences. These results suggest that both types of PFH may be based on a similar connective tissue disorder.


Decreased peripheral blood eosinophil counts in severe psoriatic patients treated with low-dose cyclosporine A. We report a clinical observation, a statistically significant decrease in peripheral blood eosinophils in patients treated with low-dose cyclosporine A for severe psoriasis 225/microliters at baseline to 114/microliters at week 12 (p = 0.04). We discuss the potential significance of this clinical finding.


Palmoplantar orthokeratotic filiform hyperkeratosis in a patient with associated Darier's disease. Classification of filiform hyperkeratosis. We present here the third published case of palmoplantar orthokeratotic filiform hyperkeratosis of particular clinical interest because of associated Darier's disease. We propose a classification of filiform hyperkeratosis in three groups on the basis of the topography (i.e. palmar and plantar, disseminated with palmoplantar sparing and linear) and the histology (i.e. porokeratosis or orthokeratosis) of the lesions. This keratinization disorder does not seem to be a specific disease entity but rather a syndrome secondary to various disorders.


Inflammatory familial palmoplantar keratoderma: Greither's disease? A case of a familial palmoplantar inflammatory keratoderma with autosomal dominant inheritance is reported. Associated clinical features included vasomotor troubles and hyperhidrosis consistent with a diagnosis of Greither's disease. Light microscopy was nonspecific. Electron microscopy showed aggregated tonofilaments around the nucleus, without true clumps. Desmosomes were numerous and cell-cell junctions showed an imbricated pattern, well demonstrated in the stratum corneum. The diagnosis of Greither's keratoderma is discussed.


A meta-analysis of studies carried out between 1946 and 1988 concerned with the efficacy of speech and language therapy treatment for aphasic patients. An examination of the empirical evidence for the efficacy of speech and language therapy treatment for adult aphasic patients is undertaken with the aid of meta-analysis which affords a statistical method of systematic data summary and synthesis. Patient characteristics and treatment outcomes are correlated to identify factors that contribute to the demonstration of a treatment effect. One of the most striking results of this retrospective study was the identification of the overwhelming failure to report data or include, in experimental controls, variables that might crucially affect outcome.


Developmental verbal dyspraxia. I: A review and critique. Developmental verbal dyspraxia is examined from four perspectives: clinical, phonetic, linguistic and cognitive. The paper critically discusses the problems encountered when criteria for identifying acquired speech disorders in the adult population are applied to children's speech difficulties without modifications. It is argued that studies of verbal dyspraxia in children have ignored the unfolding nature of this condition and that a developmental perspective has been lacking in the literature. A need for the inclusion of appropriate control groups and longitudinal case studies is identified. The issue and process of differential diagnosis are addressed and a checklist of criteria for identifying developmental verbal dyspraxia is included. It is noted that this process will inevitably be lengthy with data needed from different aspects of a child's development. Phonetic characteristics alone may not be sufficient to recognise this medical condition with its complex psycholinguistic and educational consequences.


Developmental verbal dyspraxia. II: A developmental perspective on two case studies. A longitudinal study of the speech errors of two school-age children with what was described as developmental verbal dyspraxia is presented. By comparing them with a group of normally developing children matched on articulation age, it was possible to identify speech errors not typical of earlier speech development, involving problems with syllable structure planning and vocal tract coordination. The speech-disordered children could produce more words correctly than the controls, but, when they did make speech errors, these were more serious than those found in the younger children. The speech-disordered children were followed up 4 years later. Although their speech had improved, they presented with the same profile of error types. They had increased intelligibility by adding more word-specific articulations but still had difficulties with novel and complex material. The adoption of a developmental framework in this study allowed the identification of different levels of breakdown within the speech production process. The case-study method is recommended to investigate how these levels may interact and the clinical implications of the findings are outlined.


The predictive validity and accuracy of a screening test for language delay and auditory perceptual disorder. Infants (321) who had been screened for language delay and auditory perceptual problems at 9 months of age were evaluated 1 year later. Of these infants 88.6% were correctly classified as at-risk or not-at-risk of delayed linguistic development. The correlation between performance on the screen and on a language scale was 0.49. The great majority of those with receptive and expressive delay continued to show problems at 2 years of age, whereas half of those with expressive delay alone were within normal limits. No evidence was found that a history of fluctuating hearing loss contributed to the development of either language delay or auditory perceptual problems.


The communication abilities of 2- to 4-year-old twins. The speech and language abilities of pre-school multiple-birth children (MBC) are often reported to be impaired. In this study, teh syntactic, semantic, pragmatic, articulation and phonological skills of 19 sets of MBC were assessed. The comparisons made were between MBC and matched singleton controls, between siblings within multiple-birth sets, and for each multiple-birth child with different conversational partners (sibling versus speech and language therapist). The results indicated that the MBC performed more poorly than the singleton controls on measures of syntax and phonology. Whilst there were quantitative and qualitative similarities between siblings' linguistic abilities, their phonologies were not identical, and the MBC's speech and language changed with different conversational partners. The implications of the results for the existence of 'twin language', choice of language sample for assessment of functional communication and the need for preventive intervention programmes are discussed.


A simple nasal anemometer for clinical purposes. There is a need for clinical methods which give more direct information about the behaviour of the velopharyngeal mechanism in natural speech than do the examination methods normally applied to patients suffering from velopharyngeal insufficiency. One possibility is the recording of nasal airflow in order to detect nasal emission of air. The purpose of the present study is to examine the qualities and the characteristics of a simple and cheap nasal anemometer. As this type of flowmeter is considered less reliable than most other flowmeters, its limitations must be clearly understood and accounted for in drawing conclusions. Therefore, nasal airflow in speech obtained with this flowmeter is discussed in relation to nasal airflow obtained by the more reliable pneumotachograph and in relation to nasal airflow data found in the literature. The tests made here suggest that, at least for the type of speech material and measurements used in the present study, reliable nasal airflow data can be obtained by the anemometer.


Can the Lombard effect be used to improve low voice intensity in Parkinson's disease? Low voice intensity is a common problem in Parkinson's disease. It is typically resistant to drug therapy and often persists despite extensive behavioural speech and language therapy. Based on previous findings that masking noise will produce a consistent increase in voice intensity in most normal individuals, the effects of white masking noise, presented at a sound pressure level of 90 dB, was examined in 10 parkinsonian patients with low voice intensity. Results indicated that all Parkinson's disease patients showed a marked increase in their voice intensity. Given this finding, it is proposed that masking noise may be an effective treatment for reduced voice intensity in parkinsonian speakers, particularly with the future adaptation of portable voice-activated maskers, such as the Edinburgh Masker.


Vocal attrition related to idiosyncratic dysphonia: re-analysis of survey data. In a recent survey study it was found that female army instructors were significantly more likely to suffer from symptoms of vocal attrition than new female recruits, supporting the clinical impression that those who are engaged in a vocally taxing vocation are at higher risk for vocal attrition than those who are not. In the present study we found that instructors who reported having rapid, excessive or loud speech, or a combination of these, were significantly more likely to report symptoms of vocal attrition than instructors who reported not having these speech habits. Difference in prevalence of vocal attrition symptoms among recruits with and without these speech habits was statistically non-significant. The present findings confirm the clinical impression that idiosyncratic dysphonia can increase the risk of vocal attrition, especially in people who are engaged in a vocally demanding profession or vocation.


An evaluation study of voice therapy in non-organic dysphonia. Thirty patients diagnosed as suffering from non-organic dysphonia were assigned to one of three treatment groups: direct therapy, indirect and no treatment for a period of 8 weeks. Therapeutic outcome was evaluated by independent judges, patient self-evaluation, electrolaryngograph ratings and measures of fundamental frequency. The direct treatment group showed the most significant improvement in the return to normal voice functioning followed by the indirect treatment group. One patient in the control group showed improvement without any intervention. This study provides evidence in support of the effectiveness of both direct and indirect therapy in the treatment of non-organic dysphonia and raises questions concerning individual patient responses to these approaches.


A survey of the communication-impaired population of Tayside. There are few published surveys that are designed specifically to describe the total population of clients with communication disorders who might potentially benefit from the use of a communication aid. Such data, however, would be useful in planning the funding and staffing of rehabilitation services in a region. Figures are also needed to identify populations whose needs are currently not being met and thus to establish areas of future developments both for service and research purposes. The survey reported here was carried out as part of a project concerned with the provision of augmentative communication to the neurologically impaired child and young adult. It was intended to produce a broad description of the communication-impaired population in Tayside. The survey was then used to identify detailed information about clients who may benefit from using a communication aid, and it also highlighted some provision and research issues. Access to communication aids for the non-speaking population was found to have been restricted by lack of funding, resources and opportunities for training for therapists in the use of augmentative and alternative communication. Future research and development should particularly address the needs of the aphasic population whose needs were not found to be met by currently available communication aids.


Routine quantitative analysis of brain and cerebrospinal fluid spaces with MR imaging. A computerized system for processing spin-echo magnetic resonance (MR) imaging data was implemented to estimate whole brain (gray and white matter) and cerebrospinal fluid volumes and to display three-dimensional surface reconstructions of specified tissue classes. The techniques were evaluated by assessing the radiometric variability of MR volume data and by comparing automated and manual procedures for measuring tissue volumes. Results showed (a) the homogeneity of the MR data and (b) that automated techniques were consistently superior to manual techniques. Both techniques, however, were affected by the complexity of the structure, with simpler structures (eg, the intracranial cavity) showing less variability and better spatial correlation of segmentation results between raters. Moreover, the automated techniques were completed for whole brain in a fraction of the time required to complete the equivalent segmentation manually. Additional evaluations included interrater reliability and an evaluation that included longitudinal measurement, in which one subject was imaged sequentially 24 times, with reliability computed from data collected by three raters over 1 year. Results showed good reliability for the automated segmentation procedures.


MR angiography with a cardiac-phase--specific acquisition window. A method for cardiac-phase-specific magnetic resonance (MR) angiography is presented. An electronics module permits incrementing of phase-encoding gradients and storage of incoming data only during a chosen portion of the cardiac cycle. Suppression of stationary material is maintained by delivering radio-frequency pulses at constant TR throughout the cycle. Imaging of a pulsatile flow phantom demonstrates that acquiring data only during systole substantially increases the signal intensity of flowing material. In addition, phase-encoding ghost artifacts are eliminated from the neighborhood of the vessel. Image acquisition time is minimized by acquiring only the low-frequency phase-encoding lines in the cardiac-phase-specific mode. In healthy volunteers, greatly improved MR angiograms of the lower extremities are obtained. Fat saturation and magnetization transfer further enhance vessel/background contrast. Acquiring data only during systole ensures rapid inflow for all phase-encoding lines, permitting a near-longitudinal section orientation without in-plane saturation. This substantially reduces total acquisition time relative to axial acquisition.


Effects of acceleration on the accuracy of MR phase velocity measurements. Acceleration in blood flow can affect the accuracy of phase velocity measurements. Convective acceleration is due to changes in flow geometry and is independent of the time-varying acceleration caused by flow pulsatility. To analyze the effects of convective acceleration on flow velocity measurements, phase velocity measurements were obtained in steady laminar flow in the convergent segment of a 90%, hourglass-shaped stenosis phantom at a Reynolds number of 1,500. Measurements at the stenosis indicated that convective acceleration caused the measured values of average cross-sectional velocity to deviate as much as 37% from the theoretical values. The magnitude of the error could be accounted for by including the convective acceleration term in the phase shift equation. Convective acceleration effects should not be ignored in flow velocity measurements through stenoses, even when time-dependent acceleration due to flow pulsatility can be neglected.


Magnetization-prepared MR angiography with fat suppression and venous saturation. Magnetization-prepared magnetic resonance (MR) angiography (MPMRA) is an inflow-based two-dimensional (2D) imaging sequence in which a preparation phase precedes rapid image acquisition. For maximal blood/tissue contrast, an inversion-recovery preparation nulls signal from static tissue. If needed, a second inversion suppresses signal from fat. Fully magnetized blood flows in after the inversion pulse(s), providing high signal intensity. The centric phase-encoding order, which ensures that the initial contrast is reflected in the image set, requires the use of a modified venous saturation technique. The sequence is described and its performance assessed with regard to (a) depiction of in-plane flow, (b) fat suppression, and (c) venous saturation. Phantom and volunteer studies showed good performance in all three areas. MPMRA images, acquired in just 2-4 seconds per image, had a blood/tissue contrast-to-noise ratio nearly twice that of standard 2D time-of-flight MR angiograms, acquired in 5-7 seconds. The technique is promising for restless patients and in anatomic areas plagued by motion degradation.


Phase-contrast MR angiography of vascular malformations of the spinal cord at 0.5 T. Preliminary experience with phase-contrast magnetic resonance (MR) angiography at 0.5 T applied in 12 cases of vascular malformations of the spinal cord is reported. There were six intramedullary arteriovenous malformations (AVMs), four perimedullary fistulas, and two dural arteriovenous fistulas with perimedullary drainage, all proved with x-ray angiography. The small size of the vessels and their location within a bony structure presented a technical challenge. Serpentine vascular signal patterns were identified within the spinal canal in all cases, showing good correlation with the x-ray angiographic pattern. Relative to spin-echo images, MR angiograms allowed better visualization of the venous drainage. The nidus of intramedullary AVMs was more difficult to recognize. The ability to manipulate the velocity-encoding value allows better characterization of flow speed. The results underline the two dimensions of the phase-contrast technique, which provides both anatomic images and dynamic information about vascular malformations. MR angiography does not replace selective x-ray angiography, which is indispensable for therapeutic strategy (endovascular procedure or surgery), but it can be considered a valuable alternative to x-ray angiography during follow-up.


MR imaging-histopathologic correlation of thermal injuries induced with interstitial Nd:YAG laser irradiation in the chronic model. Magnetic resonance (MR) imaging-histopathologic correlation of thermal injuries induced with interstitial laser irradiation was performed in a chronic model up to 12 weeks after laser exposure. T2-weighted MR images showed irreversible coagulative necrosis as a low-signal-intensity area. A higher-intensity surrounding area, corresponding to edema, was also present in acute lesions on T2-weighted images. Serial studies of the chronic model showed that a substantial portion of the interstitial edema zone progressed to coagulative necrosis up to 7 days after laser irradiation. This necrotic zone decreased in size beyond 2 weeks, presumably through biologic healing. MR imaging and pathologic findings correlated well in the chronic model. MR imaging has the potential to depict acute, irreversible thermal damage even before morphologic change is seen at the standard pathologic examination. Recognizing the dynamics of tissue response to interstitial laser irradiation on MR images is valuable for estimation of true lesion volume.


Dynamic image reconstruction: MR movies from motion ghosts. It has been previously shown that an image with motion ghost artifacts can be decomposed into a ghost mask superimposed over a ghost-free image. The present study demonstrates that the ghost components carry useful dynamic information and should not be discarded. Specifically, ghosts of different orders indicate the intensity and phase of the corresponding harmonics contained in the quasi-periodically varying spin-density distribution. A summation of the ghosts weighted by appropriate temporal phase factors can give a time-dependent dynamic image that is a movie of the object motion. This dynamic image reconstruction technique does not necessarily require monitoring of the motion and thus is easy to implement and operate. It also has a shorter imaging time than point-by-point imaging of temporal variation, because the periodic motion is more efficiently sampled with a limited number of harmonics recorded in the motion ghosts. This technique was tested in both moving phantoms and volunteers. It is believed to be useful for dynamic imaging of time-varying anatomic structures, such as in the cardiovascular system.


Correlation of MR changes with Doppler US measurements of blood flow in exercising normal muscle. Muscle data from phosphorus-31 magnetic resonance (MR) spectroscopy and hydrogen-1 MR imaging and popliteal artery data from duplex Doppler ultrasound were compared during an exercise test of the anterior compartment of the leg, in nine healthy volunteers. Significant variations (mean +/- standard deviation) were observed at the end of exercise versus rest in intracellular pH (pHi) (6.32 +/- 0.02 vs 7.02 +/- 0.04, P < .001), T2 (38.2 msec +/- 2.3 vs 29.5 msec +/- 1.1, P < .001), and popliteal output (652 mL/min +/- 232 vs 149 mL/min +/- 65, P < .001). These variables showed the following significant correlations at the end of exercise: T2 and pHi (r = -.784, P < .01), T2 and popliteal output (r = .737, P < .03), and pHi and popliteal output (r = -.902, P < .001). However, during recovery, the T2 curve was significantly different from those of pHi and popliteal output. This suggests that even if circulatory conditions play a role in the maximum T2 variation during exercise, they do not directly explain T2 changes. Furthermore, the correlations involving pHi suggest the role of the metabolism of exercising muscle in transcapillary fluid movement.


Altered phase-encoding order for reduced sensitivity to motion in three-dimensional MR imaging. A method of reordering phase and slab encoding that can be used to address some of the inherent problems due to motion in three dimensional imaging is described and implemented. The method is shown to be more robust with respect to reducing artifacts resulting from several fundamental types of motion. It can be readily implemented on a standard magnetic resonance imager with essentially no increase in total imaging time. Results of simulations and phantom and in vivo experiments are presented.


Occupational radiation exposure to interventional radiologists: a prospective study. This study investigates the occupational radiation dose to interventional radiologists and the operator-controlled factors that may affect dose. Thirty interventional radiologists wore radiation badges over and under lead aprons for 2 months and answered a questionnaire. The relationships between dose and caseload, case mix, experience, optional fluoroscopy features, lead apron type, and additional lead shielding were evaluated. Mean projected yearly dose (PYD) over lead was 49.1 mSv (1 mSv = 100 mrem) but was 66.6 mSv for persons performing 1,000 or more cases per year (P = .027). Mean PYD under lead was 0.9 mSv but was 1.3 mSv for persons with 0.5-mm lead coverage and 0.4 mSv for those with 1.0-mm lead coverage (P = .002). No other significant correlation was found. Conclusions are that caseload and apron thickness are the primary determinants of total body dose, that over-lead dose is high enough to warrant additional lead shielding for the head and neck, and that a double-thickness apron lowers under-lead dose by two-thirds. The large difference between under-lead and over-lead doses suggests that use of a collar badge alone for monitoring purposes is not predictive of total-body effective dose for this group of radiation workers.


MR imaging with spatially variable resolution. In some situations it may be advantageous to produce "locally focused" magnetic resonance images that have nonuniform spatial resolution matching the expected local rate of spatial variation in the object. Because such an image has fewer pixels than a conventional image with uniformly high resolution, it can be reconstructed from fewer signals, acquired in less time. This can be done by using a highly convergent representation of the image as a sum of orthonormal functions with slow (fast) spatial variation in relatively homogeneous (heterogeneous) parts of the object. Since this series is shorter than a conventional truncated Fourier series, its terms can be calculated from a subset of the usual array of phase-encoded signals. The optimal choice of these phase encodings, which are usually scattered nonuniformly in k space, results in minimization of noise in the reconstructed image. The technique is illustrated by applying it to simulated data and to data from images of phantoms.


Life tables for clinical scientists.

Life tables for clinical scientists. The life-table, or Cutler-Ederer, method of survival analysis is a simple and efficient means of estimating the probability that the first instance of an event will occur in a given period of time in studies complicated by incomplete patient follow-up. This discussion is designed to acquaint the nonstatistician with the general concepts, assumptions, advantages, and disadvantages of life-table analysis. The arcane nature of the calculations frustrates attempts at simplification. A glossary of statistical terms and sample calculations are provided for interested readers.


Cardiac metabolism in patients with dilated and hypertrophic cardiomyopathy: assessment with proton-decoupled P-31 MR spectroscopy. Proton-decoupled phosphorus-31 heart spectroscopy was performed in healthy subjects (n = 9) and patients with dilated cardiomyopathy (DCM, n = 9) or hypertrophic cardiomyopathy (HCM, n = 8). The phosphocreatine (PCr)-to-adenosine triphosphate ratio (+/- one standard deviation) after correction for blood contribution and partial saturation was significantly lower in HCM patients relative to the control subjects (1.32 +/- 0.29 vs 1.65 +/- 0.26, P < .05) but not in DCM patients (1.52 +/- 0.58 vs 1.65 +/- 0.26). The inorganic phosphate (Pi) peak was resolved only in patients with the highest spectral quality. Myocardial pH was lower in HCM patients (n = 6) relative to control subjects (n = 4) (7.07 +/- 0.07 vs 7.15 +/- 0.03, P < .05). The Pi/PCr ratio was higher in DCM (n = 3) and HCM (n = 6) patients relative to control subjects (n = 4) (0.29 +/- 0.06 and 0.20 +/- 0.04, respectively, vs 0.14 +/- 0.06; P < .05). Elevated phosphodiester signal in DCM patients correlated with 2,3-diphosphoglycerate signal (r = .94), reflecting blood pool contamination. P-31 spectroscopy enabled detection of abnormalities in cardiac metabolism and determination of pH in patients with HCM and DCM.


Correlation of MR imaging and histologic findings in mouse melanoma. M2R melanoma tumors in male C57 black mice were used to correlate magnetic resonance (MR) images with the corresponding histologic slices and to determine if analysis of the achievable correlation can provide a basis for predicting gross histologic features with MR imaging alone. The MR imaging sections obtained at 4.7 T were each 680 microns thick, with an in-plane resolution of 195 microns. The distribution of melanin within the histologic slices correlated well with the high-signal-intensity regions on the T1-weighted images (T1WIs), while these regions had low signal intensity on the T2-weighted images (T2WIs), providing evidence that melanin or melanin-associated paramagnetic species are responsible for the observed proton relaxation rate enhancement. Viable melanoma cells typically showed intermediate signal intensity on T2WIs, T1WIs, and proton-density images. Necrosis typically had high signal intensity on T2WIs, T1WIs, and proton-density images. Quantitation of the MR imaging results, followed by statistical analysis, demonstrated statistically significant differences between melanin-rich, viable-melanoma, and necrotic regions on MR images.


Long-term results of angioplasty in 110 patients with renal artery stenosis. Percutaneous transluminal renal angioplasty (PTRA) is generally considered of little benefit in the treatment of ostial renal artery stenosis. This report contains long-term follow-up (> 12 months in all patients; mean follow-up, 38 months) for 110 patients who underwent PTRA for treatment of ostial renal artery stenosis. There was no significant difference in patient benefit related to bilaterality or multiplicity of lesions treated or to renal function before angioplasty (P > .1). Although there was no statistically significant difference in benefit among groups of patients who received treatment, certain trends were apparent. The least benefit occurred in patients with insulin-dependent diabetes and those with symptoms or history of vascular disease in another organ system. Treatment of lesions with proportionately larger balloons did not result in greater benefit. Restenoses were redilated in 16 patients for whom initial treatment failed. Eleven of these were ostial restenoses. The ostial stenosis in one patient was redilated a second time. At the end of follow-up, primary, secondary, and tertiary clinical benefits were 48%, 57%, and 58%, respectively. This was not statistically different (P = .14) from a control group of 94 patients with nonostial stenoses who had 68% long-term benefit. The authors conclude that ostial renal artery stenosis is not a contraindication to PTRA, and balloon angioplasty can play an important role in blood pressure control in this patient population.


Laryngospasm after administration of gadopentetate dimeglumine. Few serious adverse reactions associated with the use of gadopentetate dimeglumine in magnetic resonance imaging have been reported. The present case involves an 8-year-old girl who developed laryngospasm after administration of gadopentetate dimeglumine.


Prolonged binding of radiolabeled recombinant tissue-type plasminogen activator after angioplasty and enclosed thrombolysis of the femoropopliteal arteries. The authors measured the binding of indium-111-labeled recombinant tissue-type plasminogen activator (rt-PA) within the recanalized femoropopliteal segment after percutaneous transluminal angioplasty (PTA) and enclosed thrombolysis. In patients with long occlusions (n = 3), 91 micrograms of rt-PA was bound 1 hour after the procedure, and the half-time of the final washout curve averaged 114 hours. After PTA in patients with multiple stenoses (n = 6), 45 micrograms of rt-PA was bound, and the half-time averaged 32 hours. These values were significantly smaller than those in patients with occlusions (P < .01). In patients with a single stenosis (n = 4), 19 micrograms of rt-PA was bound, and the half-time averaged 5 hours. These values were significantly smaller than those in patients with multiple stenoses (P < .01). The progressive accumulation of rt-PA at the sites of PTA therapy is most likely related to increasing presence of fibrin with increasing lesion severity. Fibrin accumulation may be partly responsible for early failures after PTA in extensive lesions. Removal of this fibrin with enclosed thrombolysis might improve patency.


Lumbar myelography with three-dimensional MR imaging. A strongly T2*-weighted, three-dimensional (3D) PSIF (time-reversed FISP [fast imaging with steady-state precession]) gradient-echo magnetic resonance (MR) sequence, with postprocessing of the 3D data set with a maximum-intensity projection (MIP) algorithm, produced x-ray myelography-equivalent images. The method was tested in 10 healthy volunteers to optimize sequence parameters and was evaluated in 30 patients with proven lumbar disk disease. MIP myelograms, unlike two-dimensional MR images, could not show the pathologic disks themselves but clearly demonstrated the effect on the thecal sac, giving a clear overall view of its geometry and dimensions, especially when displayed in a cine loop. All 28 medial and mediolateral disk herniations could be visualized, whereas only three of eight intraforminal disk herniations were seen on MR myelograms.


Does memory loss occur after MR imaging? In four separate studies, the existence of specific memory loss after magnetic resonance (MR) imaging at 1.5 T was assessed by means of recognition and recall tests for faces, common objects, lexical items, and by digit span, in a pre-post paradigm. Although specific memory loss was demonstrated, it was shown that the loss was not due to the main magnetic field of the imager or to radio-frequency pulse sequences, but rather to probable psychological (not physical) factors. No gross or subtle memory changes could be attributed to MR imaging, because control groups showed similar patterns of memory loss.


Preoperative embolization of the spleen in children with hypersplenism. Splenomegaly associated with myelodysplastic disorders in children may be massive and can result in pancytopenia, abdominal discomfort, and respiratory distress. When these symptoms cannot be relieved by nonsurgical means, splenectomy may be indicated. Under such conditions, surgical splenectomy carries increased risks, as the thrombocytopenia is difficult to correct secondary to splenic sequestration. Additionally, the surgical anatomy is often distorted secondary to the massive spleen and dissection can be difficult. These factors can lead to uncontrollable hemorrhage. In an attempt to decrease intraoperative blood loss, the authors successfully performed preoperative splenic artery embolization in 11 of 12 children (age range, 1-11 years) with pancytopenia due to hypersplenism. Hypersplenism requiring surgical splenectomy was due to leukemia (n = 9), myelodysplastic syndrome (n = 1), immune thrombocytopenia (n = 1), and osteopetrosis (n = 1). Embolization was performed under general anesthesia, prior to surgery, with gelatin sponge particles alone, Gianturco coils alone, or a combination of polyvinyl alcohol sponge particles and Gianturco coils. Embolization allowed for safe surgical splenectomy.


Direct aneurysm puncture and coil occlusion: a new approach to peripancreatic arterial pseudoaneurysms. A patient with pancreatitis complicated by a pseudoaneurysm in the pancreatic head was treated with a radiologic-surgical approach. At surgery, the phlegmon was exposed and treated by means of direct puncture and embolization with Gianturco coils under color Doppler flow imaging guidance.


Fluoroscopically guided percutaneous gastrostomy in children. Percutaneous gastrostomy was performed in 27 patients with ages ranging from 7 months to 18 years (mean, 8 years). Patient weights ranged from 4.7 to 73 kg (mean, 25 kg). Access to the stomach was planned and achieved with only fluoroscopic guidance. The technical success rate was 100%. Major procedure-related complications including death, sepsis, hemorrhage, peritonitis, or early tube removal did not occur. The minor complication of local skin infection occurred in six patients. Twenty-six patients (96%) tolerated tube feedings well. Mean follow-up was 184 days, and median follow-up was 103 days. At 30 days, 26 patients (96%) were alive. Percutaneous gastrostomy under fluoroscopic guidance is a safe and effective method of obtaining long-term nonparenteral nutritional access in pediatric patients.


Percutaneous gastrostomy and gastrojejunostomy after gastric surgery. The authors reviewed their experience with percutaneous gastrostomy and gastrojejunostomy in 30 consecutive patients who had undergone prior gastric surgery consisting of either partial resections (n = 24) or alteration of normal gastric anatomy (n = 6). Parameters evaluated included indications for the procedure, procedural modifications, type of prior gastric surgery, major and minor procedural complications, tube efficacy, and follow-up data. Gastrostomy tubes were placed in 27 patients for enteral feeding and in three for decompression. The success rate (100%), as well as the prevalence of major (0%) and minor (23%) morbidity--transient fever, skin infection, and high gastric residuals--were similar to those reported in patients who had not undergone prior gastric surgery. Thirty-day mortality was 13% (four patients); no deaths were related to the gastrostomy tube placement. Minor procedural modifications such as an extra-long needle, a peel-away sheath, or additional rotational fluoroscopy were necessary in 18 patients (60%). Knowledge of the postsurgical gastric anatomy is crucial in this subset of patients. Prior gastric surgery is no longer a contraindication to percutaneous gastrostomy or gastrojejunostomy tube placement.


Passive blood/contrast agent exchange in angiographic catheters and its effects on platelets. A static column of contrast agent or saline in an angiographic catheter will passively exchange with blood during angiography. The authors investigated the time course of this exchange in 5.5- and 7-F polyethylene catheters inclined at various angles. Passive blood exchange occurred 2 cm into the catheters within 7-15 seconds at most catheter tip angles, except for those catheters oriented so that their tips were nearly horizontal. In a separate series of experiments, the effect of contrast agent on platelet function and blood clotting was analyzed. The agent was sufficiently diluted in blood so as to simulate an angiographic procedure. The studies were performed in 60 cylindrical polyethylene containers with both unheparinized and heparinized blood. Use of an ionic contrast agent, more than a nonionic agent, lengthened the time for platelet aggregation (mean increases for ionic vs nonionic agents were 46.4 and 37.1 seconds, for unheparinized and heparinized blood, respectively), platelet adhesion to polyethylene surfaces (mean increases, 46.0 and 64.2 seconds), and platelet-stimulated coagulation (mean increases, 38.5 and 43.9 seconds). Conventional, intermittent flushing with saline or filling the catheter with contrast agent may be insufficient to prevent blood from rapidly back-filling the catheter tips. Contrast agents (ionic more than nonionic) distributed in the patient's blood volume inhibit platelet coating of catheter lumens and/or blood clotting under such circumstances.


Optimal central trapping (OPCETRA) vena caval filter: results of experimental studies. The authors present the in vitro and in vivo results of use of a new vena caval filter, the optimal central trapping (OPCETRA) filter. The in vitro study was designed to compare the clot-trapping effectiveness of three filters: the OPCETRA, the stainless steel Greenfield, and the original Vena Tech-LGM. Standardized 3-mm, 5-mm, and 7-mm clots were captured in 66%, 100%, and 100% of cases, respectively, with the OPCETRA filter; in 34%, 82%, and 100% of cases with the Greenfield filter; and in 50%, 100%, and 100% of cases with the LGM filter. When filters were tilted 15 degrees, 100% of the 5-mm clots were trapped with the OPCETRA filter versus 50% with the Greenfield (P < 1.04 x 10(-9)) and 70% with the LGM (P < 1.78 x 10(-5)) filters. The in vivo animal study was designed to confirm ease of placement, tolerance, and effectiveness of the OPCETRA filter in sheep. Animals were separated into two groups: Group 1 underwent embolization through the femoral vein 40 days after filter implantation and were killed immediately; group 2 underwent embolization at 90 days and were killed 8 days later. In all cases pathologic analysis on the vena cava wall was performed after resection. The in vivo study demonstrated no tilting or migration with the OPCETRA filter. These encouraging results can be explained by the filter's hourglass shape, the number of arms, and the slow release of the filter at insertion.(ABSTRACT TRUNCATED AT 250 WORDS)


Transvenous retrieval of misplaced stainless steel Greenfield filters. Transvenous retrieval was attempted in five patients following surgical misplacement of stainless steel Greenfield filters. Four filters were located within the right atrium, and one was in the left hepatic vein. All retrievals were attempted within 5 days of placement. Retrieval was successful for the four filters in the right atrium and failed for the filter in the left hepatic vein. One air embolism occurred; this was the only filter- or retrieval-related complication. Transvenous retrieval is a safe and effective minimally invasive method of removing misplaced filters.


Placement of dual bird's nest filters in an unusual case of duplicated inferior vena cava. The authors describe an unusual variant of inferior vena cava duplication, with azygos continuation of the right vena cava and hemiazygos continuation of the left vena cava, discovered at cavography in a patient with pulmonary embolism. Following unsuccessful attempts to advance titanium Greenfield filters through tortuous iliac veins, bilateral Bird's Nest filters were placed successfully.


Injection characteristics and downstream contrast material distribution of flush aortography catheters: in vitro study. Performance of 11 commercially available 4- and 5-F aortic flush catheters was evaluated with respect to the extent of upstream injection, catheter motion, and downstream homogeneity of a 10-, 15-, and 20-mL/sec bolus of 76% meglumine sodium diatrizoate at room temperature. Tests were made in a pulsatile aortic flow model containing circulating fluid isoviscous to blood. The injection process was recorded on videotape. Homogeneity of the contrast material bolus was determined spectrophotometrically from samples collected from the center and each of the four quadrants of the vessel lumen. Upstream contrast material injection between 1.5 and 7 cm in length emerged from all catheters; it was lowest with one of the "tennis racket" designs from one and a new spiral end-loop design (Halo) from another manufacturer. All catheters, except the most rigid and largest-caliber catheter (5.8 F) showed considerable shaft motion at the higher injection rates. Downstream contrast material mixing homogeneity was always best at the highest injection rate but altogether was better for the Halo catheter than for any other catheter tested. It is concluded that all tested 4- and 5-F aortic flush catheters show some undesirable features, but certain design modifications improve performance and comparative testing is helpful to distinguish such features.


Arteriography for proximity of injury in penetrating extremity trauma. Arteriography for proximity of injury was studied prospectively at a trauma center. Findings in 85 patients with penetrating extremity wounds were analyzed to determine the prevalence and types of vascular abnormalities seen with these injuries. Ninety-two limb segments were studied for 77 gunshot and 15 stab wounds. Arteriographic findings were positive in 24% overall but in only 5% for injuries confined to major vessels. A 60% positive rate was seen in a small subgroup of 10 patients with fractures due to gunshot wounds. The most frequently injured vessels were muscular branches of the deep femoral artery (59%); the most common injury was focal, non-occlusive spasm (42%). All patients were treated conservatively, without sequelae at follow-up. In this study, the vascular injuries found at arteriography for proximity of injury in penetrating trauma due to bullets of knives, particularly in the thigh, did not require surgical or radiologic intervention.


The effects of intraluminal and extraluminal drug application on secretion and smooth muscle tone in the ferret liquid-filled trachea in vitro. With the ferret liquid-filled trachea in vitro, intraluminal methacholine (MCh), phenylephrine (PE) and histamine (Hist) increased smooth muscle tone and salbutamol (Salb) decreased tone. Lysozyme output was increased by intraluminal MCh and PE. Albumin transport into the lumen was not altered by intraluminal Hist, Salb or PE. The concentration-response curves for smooth muscle contraction and for lysozyme output to extraluminal MCh lay to the left of those for intraluminal MCh. Indomethacin shifted the smooth-muscle response curves to MCh significantly to the left but did not significantly alter lysozyme output. Extraluminal MCh produced a concentration-dependent increase in albumin output whilst intraluminal MCh did so in one of three studies. Albumin output in response to MCh was not significantly altered by indomethacin. Thus, MCh has a less potent effect on smooth muscle and lysozyme secretion and, to a lesser extent, on epithelial albumin transport when given intraluminally. This may be because the epithelium restricts diffusion of the drug or due to the production of a non-prostanoid factor which inhibits smooth muscle responsiveness. Smooth muscle responsiveness is enhanced by blocking cyclooxygenase activity, suggesting MCh-induced release of a prostanoid with relaxant activity.


Localization of immunoreactive endothelin and proendothelin in the human lung. The endothelins are a family of three 21-amino-acid peptides: endothelin-1, endothelin-2 and endothelin-3. They are powerfully vasoactive, causing both contraction and relaxation of blood vessels. They are also active in the lung causing long lasting bronchoconstriction. Antibodies were raised in rabbits against the C-terminal heptapeptide of endothelin-1 (endothelin-1(15-21)) and to portions of the C-terminus of the human proendothelin-1(31-38), proendothelin-2(31-37) and proendothelin-3(31-41 amide) and tested by enzyme-linked immunosorbent assay to determine their titre and cross-reactivity. We used these antibodies to determine the localization of mature endothelin in the adult human lung and to determine the distribution of each of the three proendothelins. Mature endothelin immunoreactivity was present in airway epithelia and submucosal glands throughout the lung. In the airway epithelia immunoreactive proendothelin-1 and proendothelin-3 were detected, while immunoreactivity of all three isoforms was present in submucosal glands. Quantitative in vitro receptor autoradiography was used to locate specific endothelin binding sites. The rank order for density of endothelin binding site occurrence was: lung parenchyma greater than airway smooth muscle greater than airway epithelia. If immunoreactive endothelin is released onto these sites in vivo, endothelin may act as a paracrine mediator in the human lung.


An in vivo preparation for measurement of plasma protein and lysozyme output in the ferret tracheal lumen. An in-vivo ferret tracheal preparation has been developed to study the appearance in the liquid-filled trachea of fluorescein-labelled plasma proteins (FLP) and of lysozyme from submucosal gland serous cells. In order to investigate the influence of nervous activity on the appearance of FLP and lysozyme in the tracheal lumen, the effects of intraluminal bradykinin (an inflammatory mediator and sensory nerve stimulant), intraluminal capsaicin (a stimulant of C-fibres) and electrical stimulation of the cut peripheral end of the right cervical vagus nerve have been measured. Vagal stimulation (10 V, 10 Hz, 1 ms, 90-120 s) increased the secretory rate of lysozyme. It had no effect on FLP rate of output. Intraluminal bradykinin (100 microM) produced a small but significant increase in FLP output but had no effect on lysozyme secretion. Intraluminal capsaicin (33 microM) had no effect on FLP output and had variable effects on lysozyme output. Tracheal pressure was increased by vagal stimulation but was unaffected by bradykinin and capsaicin. Thus, bradykinin increases plasma protein output, probably by an action on the epithelium, whilst vagal stimulation and capsaicin stimulate submucosal glands. This method could be used to determine the factors which alter the rate of movement of plasma proteins into the airway lumen and the secretion of submucosal glands in vivo.


Relationship of airway responsiveness to agents causing bronchoconstriction and cough in sensitized guinea-pigs. The relationship between airway responsiveness to bronchoconstrictor- and cough-inducing stimuli has been examined in Ascaris suum-sensitized conscious guinea-pigs. Guinea-pigs were sensitized to Ascaris suum [4000 PNU and 100 mg Al(OH)3 i.p. on days 1 and 7] and then challenged with aerosolized antigen on days 21, 28 and 35. At day 35, antigen-exposure produced an early bronchoconstrictor response (EBR) and in about 50% of the animals also a late bronchoconstrictor response (LBR) commencing 4-8 h later. The bronchial responsiveness to inhaled histamine was increased in sensitized guinea-pigs and increased further 20-24 h after acute antigen challenge. Guinea-pigs developing only EBR were equally sensitive to histamine as those having both EBR and LBR. In contrast, the cough and reflex bronchoconstriction produced by inhaled citric acid (0.40 M, acting on capsaicin-sensitive sensory neurons) and cigarette smoke (3 min exposure; exciting both capsaicin-sensitive neurons and rapidly adapting stretch receptors) were not altered by sensitization. Furthermore, acute antigen challenge did not alter the effect of citric acid as measured 24 h later. The antigen-induced airway hyperresponsiveness to histamine was not accompanied by an altered sensitivity of airway sensory nerves mediating cough (and reflex bronchoconstriction), demonstrating that bronchial- (airway obstruction) and sensory- (cough) hyperresponsiveness involve separate and independent mechanisms.


The effect of GR32191 (a thromboxane receptor antagonist) on airway responsiveness in asthma. Airway responsiveness to methacholine was measured in nine subjects (22-53 years, seven male) with chronic stable asthma. All subjects were taking inhaled beclomethasone (less than 1000 micrograms daily). The mean baseline FEV1 was 2.841 (77% of predicted) and the geometric mean PD20FEV1 was 31 micrograms. After a run-in period, the subjects were randomly allocated to two treatment periods with the specific thromboxane receptor antagonist GR32191, 40 mg four times daily for 3 weeks, and identical placebo capsules. A double-blind, placebo-controlled, cross-over design was employed with 4 weeks between the two treatment periods. Treatment with GR32191 did not result in any significant improvement in mean FEV1 (2.941 after placebo and 2.861 after GR3219; F7.71 = 1.02, P greater than 0.1) or PD20FEV1 (24.3 micrograms after placebo and 38.5 micrograms after GR32191; F7.71 = 0.59, P greater than 0.1). We conclude that thromboxane is not important in the maintenance of airway hyperresponsiveness in chronic asthma and that thromboxane receptor antagonists are unlikely to provide effective treatment for this group of patients.


Capillary blood glucose monitoring.

Capillary blood glucose monitoring. The complications associated with inaccurate capillary blood glucose monitoring and poor control of diabetes are well known. This article explores the research identifying potential causes of inaccurate testing, examines ways of minimizing error and investigates quality control issues.


Chronic fatigue syndrome: cause, controversy and care. There is much controversy as to whether chronic fatigue syndrome is a physical or a psychological illness. This article reviews the literature, explains where nursing stands in the controversy and makes suggestions for nursing care.


Models of psychiatric consultation liaison nursing. Recent developments in healthcare legislation have caused nurses to examine new and innovative styles of practice. Psychiatric consultation liaison nursing promotes collaboration among healthcare practitioners, raises standards of patient care and strengthens rather than negates the traditional role of the mental health nurse.


Effects of mentorship on learners.

Effects of mentorship on learners. This small study was carried out in a unit for the care of the elderly to which second-level student nurses are allocated. No mentorship scheme was in operation in this unit and therefore the nursing officer, ward sisters, staff nurses and the nurse teacher in charge of the small school decided to compare the benefits of mentorship with non-mentorship.


The Roper nursing model as an educational and research tool. Models are thought to be of value as guides to professional practice; however, nursing models are often criticized. This article examines the concept of a model as a 'tool' and describes how the Roper model was used in a research project and proved to be both flexible and educationally sound as a teaching model.


Career development in intensive care: 1. Nursing is becoming more specialized and leaner in terms of structure and therefore competition for positions is increasing. It is essential for nurses who are considering a career in intensive care to commence the planning process as early as possible. In this, the first of two articles, intensive care nursing and the career opportunities available will be examined.


Passive euthanasia in palliative care.

Passive euthanasia in palliative care. Passive euthanasia is invariably practised in palliative care. This article aims to address the legal, moral and ethical implications of not hydrating dying patients and presents the results of a questionnaire assessing doctors' attitudes.


Patient satisfaction as a measure of quality in the care of the elderly. This article examines the relevance of obtaining patients' views in the measurement of quality in nursing care. The literature on the selection of instruments that measure quality in the care of older people is reviewed.


Effects of dipentylnitrosamine (DPNA) on the respiratory tract of rats. Wistar rats (40 males and 40 females), treated over a period of 25 weeks with subcutaneous injections of dipentylnitrosamine (DPNA) at doses of 0, 62.5, 125 and 250 mg/kg body weight showed dose-dependent, sex-related, proliferative and metaplastic alterations in the upper and lower respiratory tract within one year. The biologic behavior of the induced lung tumors is very similar to that of human lung adenocarcinomas.


Differentiation of Clara cell (distal type) antigen in human fetal bronchial epithelial cell line (HFBE). A human fetal bronchial cell line (HFBE) grew in an undifferentiated pattern under conventional culture conditions. Despite a somewhat fibroblastic shape, however, they still maintained an immuno-reactivity to cytokeratin, carcinoembryonic antigen (CEA) and epithelial membrane antigen (EMA). When grown on a collagen gel in a growth hormone-supplemented medium, their spindle shape became more conspicuous. With the additional supplement of 6 micrograms/ml vitamin A, most of the cells underwent differentiation by producing many bright inclusion bodies which proved to be strongly positive to periodic acid Schiff (PAS) and barely positive to alcian-blue (AB) staining. Electron microscopy revealed well-developed rough endoplasmic reticulum (rER), enlarged Golgi apparatus and many highly electron-dense secretory granules resembling those of Clara cells. Biochemical analysis demonstrated that HFBE cells cultured on collagen gel with vitamin A secreted products containing glycoconjugates of two different molecular weights. The higher molecular weight-product was identified as hyaluronic acid and the lower molecular weight-product as a mixture of neutral glycoproteins containing mainly N-linked glycoproteins whose glycans were of a complex type. While the secretion of hyaluronic acid was inhibited by vitamin A in a dose-dependent manner, that of the neutral glycoproteins was most enhanced by vitamin A in the range from the physiological concentration of 600 ng/ml to 6 micrograms/ml. A monoclonal antibody (SEC-41) generated against the secretory products with the lower molecular weight detected a glycoprotein of approximately 52 kd in the spent culture medium of differentiated HFBE cells. This antibody also reacted with the intra-cytoplasmic secretory granules in these cells. When tested on freeze-sectioned lung tissue, immunohistochemical reactivity of SEC-41 antibody was confined to Clara cells, some type II pneumocytes in the adult lung and respiratory epithelial cells of the fetal lung tissue. Moreover, this antibody could detect the secretory glycoproteins in the broncho-alveolar lavages (BAL) of two human cases. This paper has clearly demonstrated that cells derived from human fetal bronchial epithelium can be cultivated in an undifferentiated precursor state and under appropriate culture conditions they can be stimulated to undergo differentiation into a Clara cell type.


Immunohistochemical expression of monoclonal antibodies (epi-1 and myo-1) derived from human breast cancer against rat mammary tumors. Immunohistochemical expression of monoclonal antibodies epi-1 and myo-1 derived from human breast cancer cell line (HBC-4W) was examined for DMBA-induced rat mammary tumors. Antibody epi-1 reacted with luminal epithelial cells while antibody myo-1 reacted with myoepithelial cells of the mammary glands in rats, respectively. The reactions with both antibodies were markedly visible, in particular, in the normal mammary gland, tumor-like lesions and benign epithelial mammary tumors in rats, which showed clear two-cell-type structures. Among malignant mammary tumors, adenocarcinoma was strongly positive with antibodies epi-1 and myo-1. However, squamous cell carcinoma and adenoacanthoma mainly reacted with antibody epi-1. On the other hand, the intercellular matrices of pleomorphic cell sarcoma and stromal areas of the normal mammary gland or epithelial tumors were positive with antibody myo-1.


The rat esophagus: ultrastructure and radiological aspects of tissue response after 1320 nm Nd:YAG laser irradiation. Morphological tissue response towards laser treatment was investigated in the esophagi of adult Wistar rats by light- and transmission electron microscopy. The specimens were fixed by perfusion immediately, 2 days and 14 days after laser treatment in order to assess different stages of the healing process. The epithelium of the lasercentre was completely destroyed in the immediate group. The connective tissue showed damaged cells, fused collagenous fibres and occluded blood vessels. Smooth muscle cells presented a vacuolated sarcoplasm and pycnotic nuclei. The cross striation of skeletal muscle cells had disappeared and their nuclei were karyolytic. In a distance of 4 mm from the lasercentre all wall tissues had an almost normal appearance. After 2 days the morphological feature of the lasercentre was the same as in the immediate group. In a distance of 2 mm some layers of flat and intact epithelial cells were observed below the necrotic epithelium. The adjacent connective tissue was infiltrated by inflammatory cells. After 14 days the formation of granulation tissue had caused an occlusion of the lumen in the lasercentre. In a distance of 2 mm the lumen was patent and the wall tissues had been partly restored. As the rat esophagus serves as a model for esophagotracheal fistulae in newborn children we assume the 1320 nm Nd:YAG laser to be a possible application in occlusion of these fistulae.


Electron microscopic and 31-P NMR studies of ischemic injured rat livers during preservation and reflow. Ischemic injury induced during preservation and reperfusion contributes to post-operative failure in liver transplantation. Hepatic injury and recovery from preservation was studied in an isolated rat liver model reperfused with oxygenated erythrocytes. In order to correlate morphological and functional findings, 31-P nuclear magnetic resonance spectroscopy and electron microscopy were used to investigate metabolic and ultrastructural changes during 6 hours of reperfusion. Following cold preservation, EM's showed a primary sinusoidal cell injury, whereas the hepatocytes were well maintained. During reperfusion, hepatocytes displayed further damage. The simultaneous presence of vacuolarly degenerated mitochondria and mitochondria of increased activity was noted. 31-P NMP spectra demonstrated initially a partial ATP-recovery. The maximum level of 60% of the control ATP-value could not be further increased. EM and 31-P NMR indicate that the progressive injury to the liver is due to microcirculatory malfunction induced by an endothelial cell damage, followed by injured hepatocytes themselves, and the consequent intracellular energy crisis that is produced.


Hepatotoxicity of heated and oxygenated corn oil. The present study was undertaken in rats to examine the hepatotoxicity of ingested heated and oxygenated corn oil. Activities of serum glutamic pyruvic transaminase markedly increased in the rats given heated and oxygenated corn oil for two weeks as compared with that of the control group. In the rats given heated and oxygenated corn oil, small fat droplets were found in the liver cells, but liver cell necrosis was not seen. Ultrastructurally, there was no conspicuous change in the liver cells, except for depletion of glycogen and dilatation of cisternae of rough and smooth surfaced endoplasmic reticulum. These experimental data show that ingestion of heated and oxygenated corn oil induces hepatic injury, and that the development of hepatic injury may relate to liver cell membrane damage due to active oxygen radicals contained in heated and oxygenated corn oil.


Endogenous and exogenous factors modifying the activity of human liver cytochrome P-450 enzymes. Cytochrome P-450 dependent monooxygenases play a dual role for xenobiotic metabolism. On one hand they initiate the primary rate limiting step for the elimination of a bulk of drugs and organic chemicals. On the other hand they catalyze the formation of toxic metabolites from chemical carcinogens and many other toxic chemicals. Numerous studies have shown that their activity in animals is subject to the influence of various modifying factors, such as strain, species, sex, age, diurnal rhythm and the effect of enzyme inducers. Less is known about the influence of these factors on human cytochrome P-450 enzymes. Here we report the results of an extended study on human liver cytochrome P-450 performed with liver biopsies of 178 individuals taken for diagnostic purposes. The enzymatic activity was determined by the aldrin epoxidase assay indicating a variety of enzymes inducible by phenobarbital and by glucocorticoid and androgenic hormones. The frequency histogram of individual aldrin epoxidase activities showed a unimodal distribution and a variation factor of 100 between maximal and minimal activity. Individuals with severe liver diseases, such as cirrhosis and fatty liver, exhibited a 50% loss of enzyme activity. Age and sex did not significantly influence the enzyme activity. No significant correlation was observable between the rate of aldrin epoxidation and debrisoquine 4-hydroxylation, a prototype of a genetically controlled cytochrome P-450 reaction. We assume that the broad interindividual variation of epoxidase activities is more likely due to the influence of exogenous and endogenous inducers rather than to a genetic polymorphism.(ABSTRACT TRUNCATED AT 250 WORDS)


Glutathione homeostasis and turnover in the totally hepatectomized rat: evidence for a high glutathione export capacity of extrahepatic tissues. Glutathione (GSH) homeostasis and turnover were investigated in totally hepatectomized (HX) rats. A technique is described to remove the liver totally, with preservation of the hepatic portal and vena caval vasculature. Euglycemia could be maintained with hourly infusions of 50 mg 100 g-1 b.m. of glucose after bolus i.v. injection of glucose at the same dose. The efficiency of the animal model was demonstrated by examination of paraclinical blood parameters: progressive increases in total plasma bilirubin and alkaline phosphatase activity were noted after HX; the other parameters tested were predominantly in the normal range during the observation period of 6 hours. Histological examination revealed an acute but reversible impairment of intestine and kidneys. These results indicate that the surgical procedure and postoperative care were able to secure sufficient physiological conditions for the experiments over a longer period. 3 to 6 hours after HX we observed a decreased but stable plasma GSH level in anhepatic rats (about 50% of the control value). The GSH levels of brain and kidney were not changed. With increasing time period after HX the heart and lung GSH levels were depressed. A small depression of muscle GSH concentration was observed 4 and 6 hours after HX. A progressive increase in the concentration of oxidized glutathione was seen in brain and kidney. Our observations could be indicative for a high GSH export capacity of extrahepatic tissues contributing about 50% of the total GSH influx into circulation. Probably, the skeletal musculature is an important GSH origin for plasma.


Placental morphology and concentrations of glutathione (GSH and GSSG) and lipid peroxides (LPO) in two models of disturbed pregnancy of Uje:WIST rats. Treatment of pregnant rats with heat-denaturated bacterial material (endotoxin-model) or exposure to chronic restraint of prenatally lithium-treated pregnant dams (stress-model) were used as two models of disturbed pregnancy, both causing decreased fetal body mass. The quotient of fetal/placental mass was lowered in the endotoxin-group only. Placental mass and protein content were not changed significantly in both experimental groups, although a tendency to smaller placentae was noticed in the stress-group. Placental histology of the stress-group did not differ from untreated controls. In the endotoxin-group an altered structure of the placental barrier was observed. Small decreases of GSH and GSSG in the endotoxin-group and of GSSG in the stress-group without significant changes of the GSH/GSSG relationship were measured in homogenates of the placental labyrinth. Moderate enhancement of LPO concentration occurred in the endotoxin-group and more distinctly in two litters of the stress-group, the latter being connected with high GSSG concentrations and low fetal/placental mass-quotients.


Proliferative glomerulonephritis in mice induced by sea snake (Aipysurus laevis) venom. Aipysurus laevis venom has been shown to have a direct nephrotoxic effect in mice. A single subcutaneous injection (0.075 mg/kg body wt.) of the whole venom caused acute renal tubular degeneration and proliferative glomerulonephritis. The tubular changes appeared within 1 hour and remained for at least 14 days. Mesangial proliferative glomerulonephritis developed within 3-10 days, and is characterised by mild mesangial proliferation, mesangial and glomerular basement membrane deposits. This is followed by a partial resolution and subsequent mesangial sclerosis. The exact pathogenesis of venom-induced glomerulonephritis is not clear although it may have an immunological basis similar to that seen in human poststreptococcal glomerulonephritis. It was not possible to clarify the nature of the deposits by conventional immunohistochemical stains.


Epidermis-specific gene expression in Pachyphytum. Transcripts of exclusively epidermis-specific expression were obtained by differential screening of a cDNA library prepared from isolated epidermis tissue of a succulent plant, Pachyphytum. Six transcripts were selected and characterized by RNA gel blot hybridization. Five cDNAs represented abundant mRNAs found exclusively in the epidermis. In situ hybridizations with three of these transcripts further substantiated their epidermal location. While two transcripts were present in all cells of the epidermis, one transcript was enriched in subsidiary cells of the stomatal complexes. All of the transcripts were highly expressed in the protoderm of the shoot apical meristem. DNA sequence determination indicated that the mRNAs identified represent novel sequences, encoding yet unknown plant functions. These transcripts, their control elements, and their encoded functions should help to advance our understanding of epidermal cell determination and differentiation.


Rhizobium meliloti elicits transient expression of the early nodulin gene ENOD12 in the differentiating root epidermis of transgenic alfalfa. To study the molecular responses of the host legume during early stages of the symbiotic interaction with Rhizobium, we have cloned and characterized the infection-related early nodulin gene MtENOD12 from Medicago truncatula. In situ hybridization experiments have shown that, within the indeterminate Medicago nodule, transcription of the MtENOD12 gene begins in cell layers of meristematic origin that lie ahead of the infection zone, suggesting that these cells are undergoing preparation for bacterial infection. Histochemical analysis of transgenic alfalfa plants that express an MtENOD12 promoter-beta-glucuronidase gene fusion has confirmed this result and further revealed that MtENOD12 gene transcription occurs as early as 3 to 6 hr following inoculation with R. meliloti in a zone of differentiating root epidermal cells which lies close to the growing root tip. It is likely that this transient, nodulation (nod) gene-dependent activation of the ENOD12 gene also corresponds to the preparation of the plant for bacterial infection. We anticipate that this extremely precocious response to Rhizobium will provide a valuable molecular marker for studying early signal exchange between the two symbiotic organisms.


A maize protein associated with the G-box binding complex has homology to brain regulatory proteins. The G-box element is a moderately conserved component of the promoter of many inducible genes, including the alcohol dehydrogenase genes of Arabidopsis and maize. We used monoclonal antibodies generated against partially purified G-box binding factor (GBF) activity to characterize maize proteins that are part of the DNA binding complex. Antibodies interacted with partially purified maize GBF complexes to produce a slower migrating complex in the gel retardation assay. Immunoprecipitation experiments suggested that the protein recognized by the antibody is not a DNA binding protein in and of itself, but rather is associated with the DNA binding complex. These monoclonal antibodies were used to isolate cDNA clones encoding a protein that we have designated GF14. Maize GF14 contains a region resembling a leucine zipper and acidic carboxy and amino termini, of which the latter can form an amphipathic alpha-helix similar to known transcriptional activators such as VP16 and GAL4. Protein gel blot analysis of cell culture extract showed that a single, major protein of approximately 30 kD is recognized by anti-GF14; the protein is also present predominantly in the kernel and root. The deduced amino acid sequence of maize GF14 is more than 80% identical to Arabidopsis GF14 and Oenothera PHP-O, and is more than 60% identical to a class of mammalian brain proteins described as both protein kinase C inhibitors and activators of tyrosine and tryptophan hydroxylases. GF14 is found in a variety of monocotyledons and dicotyledons, gymnosperms, and yeast. This suggests a deep evolutionary conservation of a potential regulatory protein associated with a core sequence found in the promoter region of many genes.


TGA1 and G-box binding factors: two distinct classes of Arabidopsis leucine zipper proteins compete for the G-box-like element TGACGTGG. Regulatory elements containing the sequence ACGT are found in several plant promoters and are recognized by various basic/leucine zipper (bZIP) proteins. The Arabidopsis G-box binding factor 1 (GBF1), initially identified by its ability to bind to the palindromic G-box (CCACGTGG), also interacts with the TGACGT motif if this hexamer sequence is followed by either the dinucleotide GG--as found in the Hex motif of the wheat histone 3 promoter--or GT. Here we describe the isolation of an Arabidopsis bZIP protein, denoted TGA1, that also recognizes ACGT-containing sequences. However, TGA1 differs from members of the GBF family in the spectrum of base pair permutations flanking the ACGT sequence that are required for DNA binding. TGA1 primarily requires a TGACG motif and preferentially binds to those pentamers that are followed by a T residue. We show that although both TGA1 and GBF1 bind to the Hex motif (TGACGTGG), this binding can be distinguished on the basis of their specific DNA-protein contacts. Furthermore, TGA1 also differs from members of the GBF family in that it apparently does not form heterodimers with any member of this family.


Transactivation of geminivirus AR1 and BR1 gene expression by the viral AL2 gene product occurs at the level of transcription. Tomato golden mosaic virus is a bipartite geminivirus whose genome is divided between two circular DNA molecules. DNA A encodes functions necessary for viral DNA replication and encapsidation, whereas DNA B provides functions needed for movement in the host. Previous studies have shown that the viral AL2 gene product transactivates expression of the coat protein gene (AR1). We have investigated the role of the AL2 protein in the regulation of B component gene expression and examined the transcriptional and post-transcriptional components of this regulation. We found that AL2 protein is required for efficient expression of both the AR1 and BR1 genes, but not the BL1 gene. A comparison of steady state transcript levels and transcript levels determined by nuclear run-on analysis showed that activation of AR1 and BR1 gene expression by the AL2 protein occurs primarily at the level of transcription. These results provide an explanation for the lack of infectivity demonstrated by AL2 mutants, and suggest that the AL2 protein interacts with the cellular transcription machinery to activate the expression of rightward viral genes.


[Staphylococcus aureus nosocomial infections in an intensive care milieu (1985-1989) in Tunis]. 221 strains of Staphylococcus aureus oxacillin resistant (MetiR) caused nosocomial infections were isolated from 1985 to 1989 in a medical intensive care unit. The survey of susceptibility to antibiotics was established according to the computerized data of disk susceptibility test. The resistance phenotypes to beta-lactams, aminoglycosides and macrolides were established for epidemiological study. S. aureus infections were mainly bacteraemia (31%) and peritonitis (12%). These isolates were resistant to oxacillin with a high level (mean MIC 386 micrograms/ml). Their resistance phenotypes were MLSBc (constitutive resistance to macrolides, lincosamine and streptogramines B) in 53% and S + KGT (resistance to streptomycin, kanamycin, gentamicin and tobramycin) in 61%. All the isolates were susceptible to pristinamycin and vancomycin (MIC 0.1 and 2 micrograms/ml). These phenotypes related to the spread of multiply drug resistant strains were responsible of nosocomial outbreaks. Strains with the same pattern of resistance were isolated among the medical staff and in the environment. Infection control measures allowed to stop these outbreaks.


[The reappearance of chancroid in Algeria]. After 35 observations of the chancroid observed in the department of dermato-venereology of the University Hospital of Tlemcen (West Algeria) from August 1988 to December 1991, we are led to analyze the flare of this sexual transmitted disease. The principal affected subjects are single male no older than 30 years, having had sexual intercourse with prostitutes (30/35). Less than 10 days (19/29) after the sexual contacts, the ulcer appears, and most often unique (25/35), mildly painful, accompanied frequently by adenopathies (31/35). The contamination took place mainly in Bel Abbès--city located at 90 km from Tlemcen--(12 cases), in Tlemcen (4 cases) and Morocco (5 cases). The treatment based on sulfonamides, erythromycin and tetracycline or doxycycline, has been constantly efficient. No concomitant HIV infection has been revealed. The chancroid is the first STD observed in our department in 1991, and also, the first cause for genital ulcer.


[Drug sensitivity study of Plasmodium falciparum in the city of Yaounde (Cameroon)]. In July 1990, the in vitro chemosensitivity of 22 isolates of Plasmodium falciparum was assessed by an isotopic semi-microtest in Yaounde, Cameroon. Out of them, 54.5% were resistant to chloroquine, 28.6% to amodiaquine, 4.8% to quinine and 4.5% had a decrease of sensitivity to mefloquine. A strong positive correlation between the IC50 of the antimalarial drugs compared by pairs was detected.


[Falciparum malaria in French residents in Yaounde]. In South Cameroon, malaria is a disquieting problem. It represented 2.6% of consultants and concerned each year 10% among French residents. We have included 310 cases of Falciparum malaria between January 1, 1990 and December 31, 1990. There were 207 adults and 103 children with a mean age of 26 years. The duration of the stay was over one year in 137 cases and lower than 1 year in 183 patients. The chemoprophylaxis was correct in 194 patients according to the dose and duration. Forty-nine patients followed a combination of chloroquine and proguanil. Malaria attack was observed in 272 patients. Among them, there were 95 children. A severe malaria occurred in 38 cases. Mean parasitemia was of 0.24% (range: 0.002-7.5%). Therapy regimen was quinine: 36 cases, halofantrine: 266 cases, amodiaquine: 7 cases and association MFP (Fansimef) in 12 patients. The study shows the importance of malaria in an endemic area among expatriates despite the observance of chemoprophylactics regimens including proguanil.


[Specifics of the epidemiology of urinary schistosomiasis in Mauritius]. Early observations on this disease were made in Mauritius by Chapotin (1812) before the discovery of Schistosoma haematobium. Bulinus cernicus, the snail intermediate host, one of the nine species within the B. forskali group, is restricted to the island and the disease is not occurring in the neighbouring islands of La Reunion and Rodrigues. Under laboratory conditions, the snail susceptibility to the Mauritian strain of S. haematobium has been demonstrated. But the infection rate of the snail remains very low and the transmission of the disease is sporadic except in three foci. Its occurrence is not linked with agriculture or irrigation but is closely related to other man/water contacts in the rivers. Without clinical significant signs, the disease, quite different of the historic description, is largely underestimate. The snail is well adapted to the climatic conditions on Mauritius with a remarkably resistance to long drought periods. In fact, distribution of snail and evolution of population size fluctuate dramatically. Canalization and drainage of rivers, streams and marches since the beginning of malaria outbreak, widespread use of pesticides during the antimalaria spraying campaigns, only overhead irrigation, permanent maintenance of the lined canal system, induced many ecological constraints to possible snail habitats. Without animal reservoir of infection, control of urinary schistosomiasis or even its eradication looks feasible through a large school case-finding eventually associated with mollusciciding activities in the main foci.


[Autochthonous strongyloidiasis in the north of France]. The authors discuss four cases of indigenous strongyloidiasis, which were detected in northern France during the past twenty years. In our hemisphere, the limits of this helminthiasis range between the 50th and the 53rd parallels of latitude. In two cases, indoor contamination must be suspected; in the third case, transmission has been facilitated by insalubrity and crowding; the fourth case was related to the activities of a dustman in camping sites. Nose bleedings were noticed in two cases and the haemorrhagic manifestations in strongyloidiasis are mentioned.


[Visceral leishmaniasis in Algeria. Cases reported of visceral leishmaniasis (1985-1990)]. Following their epidemiological studies of visceral leishmaniasis in Algeria, the authors report in this survey 1122 cases diagnosed in different hospitals of the country from 1985 to 1990. The authors mention that after a temporary decline observed during the last decade, they take part to a disquieting course of this disease.


[The Anopheles fauna and the transmission of human malaria in Kinshasa (Zaire)]. A longitudinal epidemiological study of malaria and its vectors was conducted in Kinshasa. 264 night-bite collections on human bait (1,056 man nights) and 384 collections of the house-resting fauna were carried out from April 1989 to October 1990. The anophelian fauna was identified and inventoried, 7 Anopheles species were found: Anopheles gambiae, An. funestus, An. paludis, An. hancocki, An. counstani, An. brunnipes, and An. nili. A single species, An. gambiae s. l. is responsible for the transmission of malaria, it represents 93.27% of the anopheline fauna. The average number of anophele bites man day was 16.28 bites/man/night, it varied between 1 b/m/n in urban area to 26.05 b/m/n in semi-rural area. The average of the sporozoite index for An. gambiae was 3.3%, but it varied from 0% in the urban area to 6.52% in the semi-rural area. The entomological inoculation rate (h) was 197 infective bites per year. This rate fluctuated from 1 infective bite each 128 nights in urban area to 1.7 infective night-bite in semi-rural area. Other epidemiological index were also determined: the level of daily survival rate (p = 8.75 days), the vectorial capacity of 17.97 and the Macdonald's stability 3.5 bites on man taken by a vector during its entire lifetime.


[Study of phlebotomus sandflies in Syria]. An entomological survey was carried out during 1986 in ten provinces of Syria representative of the main natural areas of this country. 932 sandflies were caught with aspirators in domestic resting sites. Captures are analysed for each species.


[Survey of the infestation level of the Ixodes ricinus tick by Borrelia burgdorferi. Complimentary report]. In a recent report, we gave results of a 4 year consecutively survey (1987 to 1990) of the level of Ixodes ricinus nymphs infested by Borrelia burgdorferi in two forests of the western part of France. This brought us to conclude that there was a relative stability for this level in course of time. Results of this survey kept on in 1991 oblige us to partly modify our conclusion, on account of an important dropping of the tick infection frequency in one of the two forests, this perhaps in connection with a large observed decreasing of the micromammals populations (but not of ticks ones) due probably to an exceptional drought during all the 1990 year.


ABR screening for acoustic neuromata: the role of rate-induced latency shift measurements. The audiological assessment of patients considered 'at risk' for an acoustic neuroma is problematic when the patient has a severe hearing loss. The utility of ABR rate-induced latency shift (RLS) measurements was investigated in 189 patients who had passed a conventional assessment and 31 patients with an acoustic neuroma. A test based on the RLS of wave V using rates of 11.1 s-1 and 88.8 s-1 had a sensitivity of 89.5% and a specificity of 90.8% when applied with a dual interpretive criterion which included the loss of wave V at the higher rate. This test was included in an ABR screening protocol which had a sensitivity of 100% and a specificity of 97.9%. The RLS test requires no correction for age, sex, hearing loss or stimulus intensity and may be used in patients with severe hearing loss for whom other ABR tests are inappropriate.


Temporal modulation transfer functions for band-limited noise in subjects with cochlear hearing loss. The modulation depth required for the detection of sinusoidal amplitude modulation was measured as a function of modulation rate, giving temporal modulation transfer functions (TMTFs). The carrier was a one-octave wide noise centred at 2 kHz, and it was presented in an unmodulated background noise lowpass filtered at 5 kHz. Three subjects with unilateral cochlear hearing loss were tested. For each subject, the normal ear was tested both at the same sound pressure level (SPL) and at the same sensation level (SL) as the impaired ear. The TMTFs were essentially the same for the normal and impaired ears, both at equal SPL and at equal SL. The better ears of three subjects with bilateral cochlear losses were also tested. Again, TMTFs were essentially the same as obtained for normal ears. These results suggest that temporal resolution is not necessarily adversely affected by cochlear hearing loss, at least as measured by this task.


An audit of hearing aid quality in Denmark. This investigation was aimed towards an evaluation of the quality of hearing aids, dispensed from a National Hearing Health Service. During a twelve month period all subjects attending the hearing aid servicing section were recorded, and the reason for the visit noted. A total of 4450 people attended (45% males, 55% females) with a median age of 71 years, range 8-99 years. Among these 60.4% of attendances could be ascribed to defective hearing aids. Among the defective hearing aids 20.6% had been used less than one year and 91.4% of the defective aids had been used less than four years, that is within the guarantee period. The recording demonstrated that specific series of aids have a defect rate of 6.6-70.9% within the first year of use. A comparison between the frequency of defects in different types of hearing aids (BTE, ITE, ITC and other hearing aids) was performed indicating that there is a risk of 8.6% that BTE will be defective within one year of provision. As 20.6% of the applicants' defective hearing aids had been used less than one year, it is concluded that the quality of hearing aids should be improved; the hearing aid manufacturers' main categories for fault finding can be used in the audiological departments within the National Hearing Health Service; the recording offers valuable data on the quality of hearing aids, and specifically poor series can be revealed within a limited period.


Latency stability of auditory brainstem responses in children aged 10-12 years compared with younger children and adults. Previous articles have reported the results of using standard clinical procedures in our laboratory for testing auditory brainstem responses (ABR) in a repeated-measures design, in order to quantify ABR latency and amplitude stability in normal young adults. In a subsequent paper, these findings were extended to include the results of similar procedures in a group of seven children ranging in age from 5 to 7 years. The current experiment involves repeated-measures ABRs in a group of nine children ranging in age from 10 to 12 years. Results indicate that while these older children show the expected similarities with adults in terms of ABR peak latencies, their latency stability values are in some cases significantly lower than adults. At the same time, ABR stabilities measured in the older children show some differences compared to data from the younger children studied previously. For all groups, the same types of patterns are observed: (1) significant differences contrasting the degree of between-subject v. within-subject latency stability; (2) clear individual differences characterizing subjects; (3) within-subject distinctions according to ear of stimulation; and (4) instances of good replicability of the 'latency-stability profiles' calculated for one set of repeated waveforms v. a second set collected later in testing.


Comparison of different methods of repair of long peripheral nerve defects: an experimental study. In order to compare the performance of free nerve grafts, vascularised nerve grafts, and freeze-thawed muscle autografts for the repair of long nerve defects an experimental study was undertaken in the rabbit peroneal nerve. 5 cm defects were repaired using each method. Recovery of function was assessed after 250 days using sensory and motor physiology, and histological examination of the nerve. Reliable recovery occurred with both types of nerve graft but not with muscle grafts. Vascularised nerve grafts performed better than free nerve grafts on all parameters measured but this only reached statistical significance for sensory receptive areas and myelinated fibre diameters distal to the grafts. The role of each method of repair in peripheral nerve surgery is reviewed.


Histomorphological observations on dermal repair in expanded rabbit skin: a preliminary report. In 11 New Zealand rabbits, small tissue expanders were placed in a pocket between the dermis and the panniculus carnosus and inflated during a period of 10 days. Animals were killed immediately after the inflation procedure (Group I, N = 4), 25 days thereafter (Group II, N = 5), and 35 and 55 days thereafter (Group III, N = 2). Dermal connective tissue architecture was studied by routine light microscopy. Specimens in group I showed a striking disturbance in polarity of the dermal collagen bundles. These changes were accompanied by a clear increase of cellular infiltration. In groups II and III, the collagen polarity showed a tendency to recover to normal, while cellular infiltration was decreased. The current findings indicate that there is a spontaneous repair of the damaged dermal collagen in expanded skin with time.


The effects of ultraviolet irradiation on wound contraction in the hairless guinea pig. Ultraviolet radiation has been shown to alter wound tensile strength and evoke a number of intracellular changes in fibroblasts. We examined the effects of relatively high doses of ultraviolet radiation on subsequent wound contraction of circular wounds in the hairless guinea pig model. Female hairless guinea pigs were divided into two experimental groups receiving 80 J/cm2 or 480 J/cm2 every other day for 16 weeks. Age-matched unirradiated animals were used as controls. After exposure, all animals had either a 4 mm punch biopsy (80 J/cm2) or a 2.4 cm diameter ((480 J/cm2) Groups 3 and 4) circular area excised from the dorsum. The extent of wound enlargement immediately following wounding of the irradiated animals was decreased as compared to the controls. The rate of wound contraction was significantly lower during early stages of wound contraction in each group of irradiated animals, and wound contraction was significantly slower overall in both groups of irradiated animals compared to controls.


The beneficial effect of cyclosporin-A on the no-reflow phenomenon in rat skin island flaps. The no-reflow phenomenon is one of the factors that increase morbidity in flap and replantation surgery. Prevention and treatment of the phenomenon is an area of intense current research. This study investigated the possible effect of cyclosporin administered systemically on survival of skin flaps subjected to ischaemia-reperfusion injury. Cyclosporin treated flaps showed a statistically significant increase in survival areas regardless of the time of infusion (p < 0.01). These findings suggest that cyclosporin could be valuable in preventing or treating no-reflow in critical flaps. Possible mechanisms of action are discussed.


The effect of continuous topical application of heparin on flap survival. To evaluate the beneficial effects of heparin on flap survival area, an experimental study was carried out on dorsal flaps in rats. Topical applications of heparin, released from a silicone gel sheet onto the critical area (which generally necrosed without treatment), resulted in an increase in the flap survival area and rate as compared to controls (p < 0.01). When heparin was applied topically but solely to an area proximal to the critical area however, no increase in the survival area resulted.


Mid-facial sensation following craniofacial surgery. During mid-face advancement and correction of orbital dystopia, the infraorbital nerves are always stretched and displaced by the orbital floor osteotomies and bone displacement, and are at risk of damage. We have found no published work that has investigated the function of the infraorbital nerves following elective craniofacial procedures. In this study the cheek sensation and tooth sensibility in 20 patients who have had either mid-face advancement or correction of orbital dystopia was assessed. The function of the infraorbital nerve is largely undisturbed by the osteotomies and bone displacement performed during these procedures. A small proportion of patients could not feel cold in their anterior maxillary teeth, suggesting that there is damage to the anterior superior alveolar nerve branch of the infraorbital nerve.


Critical analysis of methods of reconstruction of exenterated orbits. Reconstructive procedures were used on 14 patients who had undergone orbital exenteration and radiotherapy for malignant tumours. All patients were tumour free after a follow-up of between 5 and 18 years. Reconstruction was carried out in 3 stages. In the first operation the orbit was filled, in the second the orbital rims and eyelids were shaped, and in the third a cavity for a static eye prosthesis was created. Critical assessment of results showed that the first stage alone produced a marked improvement in appearance and occluded existing fistulae. The subsequent procedures improved aesthetic results further. Difficulties were encountered from retraction of the tissues and insufficient tissue mobility.


Tissue expansion in the treatment of tubular breast deformity. Four cases of tubular breast deformity were treated using tissue expansion. The expanders were inserted through either an axillary or an infra-mammary approach in as low a position as possible. The expanders were then over-inflated and allowed to settle for a period of time before removal and insertion of a permanent implant. We present our experience using this technique and the complications and problems we had to deal with.


Lignocaine vs bupivacaine in prominent ear correction: a controlled trial. Thirty patients were assigned to two equal groups to compare the effects of ear infiltration with bupivacaine versus lignocaine prior to correction of prominent ears. There was a statistically significant decrease in narcotic requirement in the first 4 h postoperatively in the bupivacaine group, associated with a decrease in the antiemetic requirement. The choice of local anaesthetic did not significantly affect the incidence of vomiting.