The effect of antihypertensive therapy on the course of renal failure. The course and prognosis of chronic renal failure are much worse in hypertensive patients than in normotensive patients with otherwise similar basic disease. Therefore, antihypertensive measures with a combination of diuretics, beta-blockers, and vasodilators have clearly been shown to improve the progression of diabetic nephropathy. Treatment of hypertension with angiotensin-converting enzyme (ACE) inhibitors has also been shown to have a favorable effect on the prognosis of chronic renal failure. In the past few years, more knowledge about the pathogenesis of hypertension and the development of hypertension-induced organ damage has been followed by changing attitudes to antihypertensive therapy and the introduction of calcium antagonists for the treatment of hypertension, even in chronic renal failure. ACE inhibitors and calcium antagonists seem to be advantageous in the prognosis of chronic renal failure as they act on the humoral and trophogenic factors now known to be important in antihypertensive therapy.


Nilvadipine in hypertension with renal dysfunction. The pharmacokinetics and pharmacodynamics of nilvadipine, a new dihydropyridine calcium antagonist, were examined in 16 patients divided into two different population groups. The first group of eight patients had arterial hypertension with limited renal function (creatinine clearance of 15-50 ml/min). The second group of eight patients had arterial hypertension with no concomitant renal dysfunction (creatinine clearance over 80 ml/min). Following a 1-week placebo washout period, all patients were given 8 mg of nilvadipine once daily for 10 days. The diastolic blood pressure (24-h postdose) fell in group I from a mean of 100.5 to 91.5 mm Hg and in group II from a mean of 106.7 to 88.2 mm Hg, which was significant in comparison to the placebo period. In neither group was there a significant change in heart rate, renin and aldosterone plasma levels, serum electrolytes, or sodium and potassium excretion. The pharmacokinetics of the unchanged nilvadipine were not significantly different between group I and group II. Neither group showed unchanged nilvadipine in urine. There was a slight increase in plasma levels of the inactive main metabolites M3 and M7; there was correspondingly less M3 found in the urine of group I patients. Nilvadipine appears to be an effective hypotensive agent at single daily doses of 8 mg. This dosage was well tolerated. The findings of this study did not suggest that lower doses need to be given to patients with limited renal function, at least not those with a creatinine clearance between 15 and 50 ml/min.


In situ hybridisation: a review of methodologies and applications in the biomedical sciences. In situ hybridisation methodology is reviewed with particular emphasis on the latest modifications of technique. Methodology is evaluated, with suggestions on how to maximise its successful application. Emphasis is placed upon non-radioactive techniques which can be used by morphologically orientated laboratories, and details of the use of digoxigenin-labelled oligonucleotide probes are given special mention. Recent applications in morphology, and neurobiology, virology, pathology and cytogenetics are detailed. Developments where significant advances have been made in the biomedical sciences are highlighted.


A modified Ziehl-Neelsen stain for mycobacteria. For the preliminary detection of mycobacteria in routine pathology specimens heavy reliance is placed on staining methods. Difficulties encountered with a cold-staining method, which had possibly gone un-noticed for several years despite a quality control check programme, are described. An alternative to the 'classical' Ziehl-Neelsen stain is described, which although devised initially as a 'stop-gap' is still in use eight years later.


Spinal versus epidural anesthesia during transurethral resection of the prostate. The operative superiority of epidural anesthesia during transurethral resection of the prostate (TURP) stimulated this study. Twenty patients scheduled for TURP were randomly allocated to receive either spinal anesthesia (n = 10) with 8 ml bupivacaine 0.5%+ 5ml lignocaine 2%. During and after the operative procedure, PR, BP, ECG, and pulse oximetry were monitored, and blood Hb and Hct, plasma free Hb, and serum sodium and potassium levels were measured. Both techniques resulted in similar PR and BP changes. TURP with spinal anesthesia resulted in more prolonged period of hyponatremia and more increased duration of raised plasma free Hb.


Molecular cloning, nucleotide sequence and expression of a cDNA encoding an intracellular protein tyrosine phosphatase, PTPase-2, from mouse testis and T-cells. The PTP-2 cDNA encoding an intracellular protein tyrosine phosphatase (PTPase-2) was isolated and sequenced from mouse testis and T-cell cDNA libraries. This PTP-2 cDNA was found to be homologous to human PTP-TC and rat PTP-S, and contained 1,551 nucleotides, including 1,146 nucleotides encoding 382 amino acids as well as 5' (61 nucleotides) and 3' (344 nucleotides) non-coding regions. Northern blot analysis indicated that PTP-2 mRNA of 1.9 Kb was most abundant in testis and kidney, although it was also present in spleen, muscle, liver, heart and brain.


Development of infants with disabilities and their families: implications for theory and service delivery. This Monograph presents the results of a nonexperimental, longitudinal investigation of developmental change in 190 infants and their families after 1 year of early intervention services. The Early Intervention Collaborative Study (EICS), conducted in association with 29 community-based programs in Massachusetts and New Hampshire, was designed to assess correlates of adaptation in young children with disabilities and their families over time, to inform social policy by analyzing the influences of family ecology and formal services on child and family outcomes, and to generate conceptual models to guide further investigation. The study sample (mean age at entry = 10.6 months) includes 54 children with Down syndrome, 77 with motor impairment, and 59 with developmental delays of uncertain etiology. Data were collected during two home visits (within 6 weeks of program entry and 12 months later) and included formal child assessments, observations of mother-child interaction, maternal interviews, and questionnaires completed independently by both parents as well as monthly service data collected from service providers. Child and family functioning varied considerably. Developmental change in the children (psychomotor abilities, adaptive behavior, spontaneous play, and child-mother interaction skills) was influenced to some extent by gestational age and health characteristics, but the strongest predictor of change was the relative severity of the child's psychomotor impairment at study entry. Families demonstrated generally positive and stable adaptation (in terms of the effect of rearing a child with disabilities on the family, parenting stress, and social support), despite persistent challenges with respect to mother-child interaction and differences in reported stress between mothers and fathers. Documentation of services revealed that early intervention is a complex and multidimensional experience that spans multiple public and private systems. Vulnerable and resilient subgroups within the sample were identified, and different correlates of adaptive change were demonstrated. Results of data analyses suggest new perspectives on the study of early childhood disability. The implications of the findings for developmental theory and social policy are discussed.


Abnormal distribution of desmin and vimentin in myofibers in adult onset myotubular myopathy. We report, for the first time, muscle immunocytochemical studies in sporadic, adult onset myotubular myopathy (SAOMM), which show intramyofibrillar central, perinuclear desmin and vimentin. This pattern was absent in a normal control and in myofibers with increased internal nuclei associated with denervation and myotonic muscular dystrophy (MyD). These findings resemble those reported in 8- to 15-week-old human fetal myotubes and myofibers of infantile MM, implying a possible regression of intermediate filaments of adult myofibers to an early developmental phase in SAOMM.


Expression of glial fibrillary acidic protein (GFAP) by cultured angiofibroma stroma cells from patients with tuberous sclerosis. Large dendritic cells were cultured from facial angiofibromas of six patients with tuberous sclerosis. The cells were examined immunocytochemically for expression of selected cytoskeletal and non-structural proteins and the results compared with the staining profiles obtained with normal skin fibroblasts and normal glial cells. In similarity to normal glia, the angiofibroma stroma cells expressed glial fibrillary acidic protein (GFAP). Conversely, by analogy to fibroblasts, the abnormal stroma cells produced fibronectin and did not react with the antibody to S-100 protein. By immunogold labelling it was established that GFAP and vimentin were co-localized in intermediate filaments of the angiofibroma cells.


An assessment of the proliferative potential of 'balloon cells' in focal cortical resections performed for childhood epilepsy. Cerebral cortical dysplasia is an uncommon pathological substrate of severe intractable childhood epilepsy, sometimes treated by hemispherectomy. Neuropathological findings include abnormal gyrus formation, loss of cortical lamination, unusual giant neurons and 'balloon cells' of indeterminate histogenesis similar in appearance to neoplastic gemistocytic astrocytes. In order to investigate the proliferative potential of 'balloon cells', we used Crocker's silver impregnation technique to demonstrate nucleolar organizer regions (AgNORs) involved in cellular proliferation, together with immunohistochemical evaluation of proliferating cell nuclear antigen (PCNA) expression. Balloon cells (5.56 +/- 0.24) had significantly (P < 0.001) greater AgNOR numbers than reactive astrocytes (3.89 +/- 0.15), neurons (2.30 +/- 0.13) or giant neurons (4.26 +/- 0.20). However, when corrected for nuclear size, results showed that 'balloon cells' (0.093 +/- 0.006) had significantly (P < 0.001) fewer AgNORs/square micrometre of nuclear area than reactive astrocytes (0.225 +/- 0.016) and had significantly (P < 0.001) more AgNORs/square micrometre of nuclear area than normal (0.048 +/- 0.003) or giant neurons (0.054 +/- 0.003). On the assumption that astrocytes are typical interphase cells and that normal neurons are post-mitotic, the results suggest that 'balloon cells' are unlikely to be undergoing proliferative activity and, when adjusted for nuclear size, the number of AgNORs/unit of nuclear area is more reflective of cellular ploidy than of proliferative activity in non-neoplastic neural tissues. The virtual absence of PCNA expression by 'balloon cell' nuclei supports such an interpretation of the AgNOR results.


Comparison of modified Bielschowsky silver impregnation and anti-ubiquitin immunostaining of cortical and nigral Lewy bodies. We have compared the sensitivity of a modified Bielschowsky silver impregnation with that of anti-ubiquitin immunostaining for the detection of Lewy bodies in five cases of diffuse Lewy body disease. In two of the cases there were neuritic plaques and neurofibrillary tangles within the neocortex in sufficient numbers to warrant an additional diagnosis of Alzheimer's disease. The modified Bielschowsky technique was as effective as anti-ubiquitin immunohistochemistry at demonstrating cortical Lewy bodies in 7 micron-thick paraffin sections. As might therefore be expected, silver impregnation of 20 micron-thick sections revealed significantly more cortical Lewy bodies than did the immunostaining of 7 micron-thick sections (P = 0.004). The silver impregnation had the further advantage of allowing much better visualization of the Alzheimer-type changes. In contrast to the cortical-type Lewy bodies, the dense-core type present in sections of midbrain were relatively poorly impregnated by the modified Bielschowsky method, possibly reflecting differences in the composition of the two types of inclusion.


Response of hypothalamic peptide mRNAs to thyroidectomy. Using in situ hybridization histochemistry, we have investigated the effect of thyroid hormone on the expression of several peptide mRNAs in the hypothalamic paraventricular nucleus (PVN) of adult male rats. Hypothyroidism was induced by surgical ablation of the thyroid gland. The animals (control sham-operated, thyroidectomized, thyroidectomized+T4 replaced rats) were studied 28 and 50 days after surgery. Sections of the PVN were hybridized using synthetic oligonucleotide probes complementary to mRNA for thyrotropin-releasing hormone (TRH), corticotropin-releasing hormone (CRH), galanin (GAL), enkephalin (ENK), neurotensin (NT), vasoactive intestinal polypeptide (VIP) and vasopressin (VP). GAL mRNA was also analyzed in the anterior paraventricular, arcuate, and dorsomedial nuclei of the hypothalamus. At the PVN level, a feedback effect of thyroid hormone on TRH synthesis was demonstrated by the TRH mRNA increase in hypothyroidism and by its decrease in hyperthyroidism. Hypothyroidism caused a dramatic decrease in GAL mRNA in parvo- and magnocellular PVN neurons both 28 and 50 days after thyroid ablation, whereas no effect was seen in VP mRNA, the main peptide hormone coexisting with GAL. The T4 replacement prevented the GAL mRNA impairment. Hypothyroidism did not influence GAL mRNA in the anterior PVN, perifornical area or in the arcuate nucleus, whereas a decrease in GAL mRNA was observed in the dorsomedial nucleus. VIP mRNA, which is undetectable in the PVN of normal animals, was present in several PVN neurons after thyroidectomy. CRH mRNA was decreased after thyroidectomy, whereas the T4 restitution caused an upregulation. The levels of ENK or NT mRNA were not significantly affected by the thyroid status. The present results show that, in addition to TRH mRNA, other hypothalamic peptide mRNAs are affected by thyroid hormone levels.


Transient outward currents in cochlear ganglion neurons of the chick embryo. Cochlear ganglion neurons were isolated from chick embryos and membrane currents recorded using the patch-clamp technique. Depolarizing voltage steps elicited transient outward currents whose inactivation was best fitted by a double-exponential function with time constants < 30 ms and > 100 ms. The fast inactivating transient outward current (Ito,f) had a threshold for activation of -61 +/- 5.5 mV; steady-state inactivation was voltage-dependent between -90 and -60 mV, with half-inactivation near -75 mV. The slowly inactivating outward current (Ito,s) showed an activation threshold of 34 +/- 4 mV. Half-inactivation was at -67 +/- 3 mV. Ito,f was blocked by 4-aminopyridine which did not affect Ito,s. The effect was concentration- and voltage-dependent. Tetraethylammonium had no effect on either fast or slow transient currents but reduced the amplitude of the non-inactivating outward current in a dose-dependent manner. Ito,f was strongly inhibited by removing Ca2+ from the extracellular bathing solution. Cobalt ions inhibited Ito,f in a dose-dependent manner between 2 and 20 mM. The inhibitory effect of Co2+ was voltage-dependent, displaying a bell-shaped inhibition curve as a function of membrane voltage, maximal inhibition occurring between -20 and 0 mV. Ca2+ removal did not affect Ito,s and partially reduced the amplitude of the steady-state current. These results provide kinetic and pharmacological evidence for the presence of two distinct transient outward currents in cochlear neurons. These currents may play a role in the first synaptic relay of sound transmission.


Spinal substance P and N-methyl-D-aspartate receptors are coactivated in the induction of central sensitization of the nociceptive flexor reflex. We have studied the effects and interactions of the neurokinin-1 receptor antagonist CP-96,345 and the N-methyl-D-aspartate receptor/channel blocker MK-801, both applied intravenously, on the flexor reflex and on the facilitation of the flexor reflex by conditioning stimulation of cutaneous C-afferents in decerebrate, spinalized, unanesthetized rats. The flexor reflex was evoked by subcutaneous electrical stimuli applied to the sural nerve innervation area 1/min at an intensity that activated C-fibers and was recorded as electromyogram from the ipsilateral hamstring muscles. The magnitude of the baseline flexor reflex was usually highly stable in the course of the experiments without experimental manipulations. The same stimulus was used as a conditioning train (0.9 Hz, 20 shocks) and caused a brief facilitation of the flexor reflex, which was maximal 0.5 and 1 min after stimulation (255.1 +/- 23.6% over baseline). During the course of the conditioning stimulus train, the reflex magnitude was gradually increased (wind-up). MK-801 (0.1 and 0.5 mg/kg) consistently depressed the polysynaptic flexor reflex. At a dose of 0.5 mg/kg, but not 0.1 mg/kg, MK-801 reduced the wind-up and blocked the facilitation of the flexor reflex induced by the conditioning stimulus by 90%. The facilitatory effect of 7 pmol intrathecal substance P was also partially reduced by MK-801. CP 96,345 (1 and 3 mg/kg) did not depress the flexor reflex, but dose-dependently antagonized reflex facilitation by the conditioning stimulus train, similarly to its antagonism of intrathecally applied 7 pmol substance P-induced facilitation.(ABSTRACT TRUNCATED AT 250 WORDS)


Direct projections from the central amygdaloid nucleus to the globus pallidus and substantia nigra in the cat. Employing both anterograde and retrograde axonal tracing, we investigated direct projections from the central amygdaloid nucleus to the basal ganglia in the cat. The anterograde axonal tracing of Phaseolus vulgaris-leucoagglutinin revealed that projection fibers from the central amygdaloid nucleus to the basal ganglia ended in the globus pallidus (the feline homolog to the external segment of the globus pallidus of primates) and substantia nigra. The amygdalopallidal fibers terminated chiefly in the medial most part of the globus pallidus at its caudal level. The amygdalonigral fibers terminated densely in the substantia nigra pars lateralis, and moderately in the dorsolateral part of the substantia nigra pars reticulata; none of them were found to end in the substantia nigra pars compacta. Both of the amygdalopallidal and amygdalonigral projections were ipsilateral. These neuronal connections were confirmed by retrograde axonal tracing of cholera toxin B subunit in the second set of the experiments: The cells of origin of the amygdalopallidal and amygdalonigral projections were located predominantly in the lateral part of the central amygdaloid nucleus, and additionally in the intercalated cell islands of the amygdala. Most of them were of small bipolar or multipolar type. The cells projecting to the globus pallidus were preferentially distributed at the rostral levels of the central nucleus and intercalated cell islands of the amygdaloid complex, while those projecting to the substantia nigra were mainly located at the caudal levels of these amygdaloid subdivisions. In the third set of the experiments, sequential double-antigen immunofluorescence histochemistry for transported cholera toxin B subunit and horseradish peroxidase showed that some single neurons in the lateral part of the central amygdaloid nucleus, particularly at its middle level, issued axon collaterals to both the globus pallidus and substantia nigra pars lateralis. The results of the present study indicate that the central amygdaloid nucleus sends projection fibers to the globus pallidus and substantia nigra possibly to exert a limbic influence upon forebrain motor mechanisms.


Immunohistochemical localization of argininosuccinate synthetase in the rat brain in relation to nitric oxide synthase-containing neurons. The distribution of the urea cycle enzyme, argininosuccinate synthetase, in the rat brain was determined using immunohistochemistry. This enzyme participates in the only known metabolic pathway for citrulline, its condensation with aspartate to form argininosuccinate, which can then be cleaved to fumarate and arginine. It may thus provide a mechanism to recycle citrulline, formed in the nervous system via nitric oxide synthase activity, back to the nitric oxide precursor, L-arginine. Argininosuccinate synthetase immunoreactivity was detected in discrete populations of neurons throughout the brain. Double-staining with nicotinamide adenine dinucleotide phosphate (reduced form)-diaphorase histochemistry for the localization of nitric oxide synthase demonstrated that argininosuccinate synthetase coexists with nitric oxide synthase in some brain regions. However, many neurons were found that contained one of these two enzymes, but not the other. Thus some nitric oxide synthase-containing neurons appear able to recycle citrulline via argininosuccinate, while others do not. Additional roles for argininosuccinate synthetase in the brain are discussed.


Histochemical localization of nitric oxide-synthesizing neurons and vascular sites in the guinea-pig intestine. Laminar preparations of fixed segments of the guinea-pig intestine were examined for nitric oxide synthase activity using reduced nicotinamide adenine dinucleotide phosphate and nitroblue tetrazolium salt as substrates. Under conditions specific for detecting nitric oxide synthase-related diaphorase activity, a subpopulation of neural elements in the myenteric plexus, deep muscular plexus and submucosa were intensely stained. Intensely stained nerve fibres were distributed throughout the meshworks of the myenteric plexus and its innervation of the circular muscle, and in the submucosa within Henle's plexus. Intensely stained nerve cells and their processes were evident in most myenteric ganglia but were rare in ganglia of Henle's plexus. Stained ganglion cells comprised types I, II and VI of the morphologically defined enteric nerve cells. Stained neural elements were increasingly prevalent within successively more caudal segments of the intestine. In addition to neuronal staining, arterioles of the submucosal vascular network displayed distinct, punctate patches of staining distributed over their surface. Perivascular nerve fibre staining was absent. These results show nitric oxide synthase activity to be present within neurons and fibres of the major enteric nerve layers and within submucosal blood vessels throughout the guinea-pig small and large intestine.


Modulation of GABAA receptor-activated current by norepinephrine in cerebellar Purkinje cells. Previous studies employing extracellular single-unit recording in the intact cerebellum have demonstrated that norepinephrine can potentiate GABA-induced suppression of Purkinje cell spike activity. However, many issues related to the nature of this modulatory phenomenon remain to be resolved. Using whole-cell patch clamp recording, the present study investigated the effect of norepinephrine on GABA-activated membrane currents (IGABA) in solitary Purkinje cells isolated from neonatal rat cerebella following acute dissociation. Exposure of Purkinje cells to norepinephrine at a concentration which, by itself, had no obvious effect on Purkinje cell membrane conductance, consistently augmented IGABA. The catecholamine also potentiated GABA-gated chloride currents as well as muscimol-induced currents in Purkinje cells. Thus, the facilitating effect of norepinephrine on IGABA was attributed to an interaction between norepinephrine and the GABAA receptor-mediated chloride conductance. The effect of norepinephrine could be mimicked by isoproterenol as well as by 8-bromo cAMP, suggesting that a beta-receptor-mediated, cAMP-dependent cascade may underlie the observed heteroreceptor interaction. Our results establish the existence of a postsynaptic mechanism by which norepinephrine, through activation of the beta-adrenoceptor, may modulate GABAA receptor function in cerebellar Purkinje cells. This study provides the groundwork for a detailed investigation into the cascade of membrane and intracellular events underlying such a synergistic modulatory interaction at the cellular and subcellular levels.


Transmitter diversity in carotid body afferent neurons: dopaminergic and peptidergic phenotypes. Hypoxic stimulation of carotid body chemoreceptors is conveyed to the brainstem by primary sensory neurons whose peripheral axons run in the carotid sinus nerve. While considerable attention has focused on defining chemical neuroregulators released by glomus cells in the carotid body, our understanding of the morphology, distribution and transmitter phenotype of these carotid body afferent neurons remains limited. Carotid body afferent neurons were labeled by microinjection of the retrograde tracer, Fluorogold, into the vascularly isolated rat carotid body. In addition, immunoelectron microscopy was used to correlate transmitter phenotype with ultrastructural features of afferent terminals in the carotid body. Our results indicate that 41% of all carotid body afferent neurons express tyrosine hydroxylase, the rate-limiting enzyme in catecholamine biosynthesis, whereas 7% contain substance P. Tyrosine hydroxylase- and substance P-positive neurons constitute separate subpopulations of carotid body afferents, as these two phenotypes were not colocalized. Most of the tyrosine hydroxylase-containing carotid body afferent neurons were small- or medium-sized (mean cell diameter 15-20 microns) and located in the distal petrosal ganglion, whereas the majority of substance P-containing carotid body afferent neurons were medium- to large-sized (mean cell diameter 20-29 microns) and located in the proximal petrosal ganglion and jugular ganglion. These differences strengthen the notion that these catecholaminergic and peptidergic carotid body afferent neurons give rise to functionally distinct subsets of chemoafferent fibers. To further characterize the catecholaminergic phenotype expressed by tyrosine hydroxylase-positive cells in the petrosal ganglion, we examined the colocalization of tyrosine hydroxylase and DOPA decarboxylase, the dopamine-synthesizing enzyme. Eighty-six per cent of tyrosine hydroxylase-positive neurons in the distal petrosal ganglion also contained DOPA decarboxylase; as these cells do not express the norepinephrine-synthesizing enzyme, dopamine beta-hydroxylase, these data indicate that the catecholaminergic carotid body afferent neurons are dopaminergic. Finally, ultrastructural analysis of the peripheral processes of tyrosine hydroxylase-positive afferent terminals in the carotid body demonstrated endings in close opposition to Type I glomus cells, consistent with a role for dopaminergic afferent neurons in carotid body chemoreception. One possibility is that these cells, in addition to their role as afferents, constitute a morphologic substrate for dopaminergic "efferent" inhibition in the carotid body.


A calcium-permeable channel in the apical membrane of primary cultures of the rabbit distal bright convoluted tubule. Calcium is actively reabsorbed in the distal nephron segments and recent studies have demonstrated the presence of Ca2+ channels in these epithelial cells, which could be involved in transepithelial transport. To test this possibility, single-channel currents were recorded by the patch-clamp technique in the apical membrane of primary cultures of the rabbit distal bright convoluted tubule cells (DCTb). In the cell-attached mode with 100 mmol/l BaCl2 in the pipette and 145 mmol/l NaCl in the bath, inward negative currents, consistent with Ba2+ currents, were recorded. In these conditions, the single-channel conductance was 15 pS. In excised inside-out patches, the single-channel conductance was 13 pS and the current reversal potential of +60 mV was close to the Nernst equilibrium potential for Ba2+ (> +58 mV). Similar experiments conducted with Ca2+ as the main charge carrier showed that this ion was less permeant through the channel than Ba2+ (PBa/PCa approximately 1.4). We also showed that the Ca(2+)-channel blocker, lanthanum (1 mumol/l La3+), added on the cytosolic side of the membrane, reversibly blocked the channel activity. On the other hand, verapamil (0.1 mmol/l) and nifedipine (10 mumol/l), perfused on the cytosolic side of the membrane, abolished the channel activity but this effect was not reversible. Another type of channel was also identified in the apical membrane of cultured DCTb cells. Ion-substitution experiments showed that this 21-pS conductance channel did not discriminate between Na+ and K+ and did not conduct Ba2+.(ABSTRACT TRUNCATED AT 250 WORDS)


Large-conductance chloride channels of new-born rat cardiac myocytes are activated by hypotonic media. Large-conductance chloride (LC-type Cl-) channel activity was studied in rat ventricular myocyte membrane during development. In contrast with results previously obtained in cultured ventricular myocytes of the new-born rat, we failed to record single-channel activity in freshly isolated myocytes whatever the age of the animal (from 2 days old to adult) and the recording patch configuration used. However, spontaneous single-channel activity of LC-type Cl- channels was recorded in bleb membranes of myocytes of rats younger than 12 days, with a higher frequency in excised inside-out membrane patches than in cell-attached membrane patches. In intact neonatal myocytes, application of hypotonic media (150 mOsm) also initiated the channel activity, after variable delays (25-200 s). The channel could not be activated by suction applied through the pipette and was not observable in cells from rats older than 15 days. The LC-type Cl- channels showed properties similar to those reported in other preparations and previously observed in cardiac cultured cells: they had a large single-channel conductance of 400 pS in symmetrical 150 mM NaCl, showed multiple subconductance states, a relatively high selectivity to Cl- ions over Na+ ions (PCl/PNa = 24.6), were blocked by 10 microM 4-acetamido-4'-isothiocyanatostilbene-2,2'-disulphonic acid (SITS) and showed voltage-dependent inactivation. They were not activated by 10 microM colchicine or 3 microM cytochalasin D.(ABSTRACT TRUNCATED AT 250 WORDS)


Chloride and potassium conductances of cultured human sweat ducts. The purpose of this study was to characterize the ion conductances, in particular those for Cl- and K+, of human sweat duct cells grown in primary culture. Sweat duct cells from healthy individuals were grown to confluence on a dialysis membrane, which was then mounted in a mini-Ussing chamber and transepithelial and intracellular potentials were measured under open-circuit conditions. Under control conditions the epithelia developed mucosa-negative transepithelial potentials, Vte, of about -10 mV. The apical membrane potential, Va, was -25 mV to -30 mV (n = 97) in most cells, but several cells had a higher potential of about -55 mV (n = 29). Mucosal amiloride (10 mumol/l) hyperpolarized Va from -31 +/- 1 mV to a new sustained level of -46 +/- 2 mV (n = 36). These changes were accompanied by increase in the fractional resistance of the apical membrane, fRa, and decreases of Vte and the equivalent short-circuit current, Isc. In amiloride-treated tissues an increase in mucosal K+ concentration (5 mmol/l to 25 mmol/l) depolarized Va by 5 +/- 1 mV (n = 8), while the same step on the serosal side depolarized Va by 20 +/- 2 mV (n = 8). A Cl- channel blocker 3',5-dichlorodiphenylamine-2-carboxylate DCl-DPC; 10 mumol/l) depolarized Va by 5 +/- 1 mV (n = 6), an effect that was lost after amiloride application. The blocker had no effect from the serosal side. Reduction of mucosal Cl- (from 120 to 30 or 10 mmol/l) depolarized Va by 9-11 mV (n = 35), an effect that was often followed by a secondary hyperpolarization of 10-30 mV (n = 27).(ABSTRACT TRUNCATED AT 250 WORDS)


The outwardly rectifying Cl- channel is not involved in cAMP-mediated Cl- secretion in HT-29 cells: evidence for a very-low-conductance Cl- channel. The patch-clamp technique and transepithelial current measurements in conjunction with analysis of transepithelial current noise were employed in order to clarify the role of the outwardly rectifying, depolarization-induced Cl- channel (ORDIC) during cAMP-mediated Cl- secretion in HT-29/B6 cells. Confluent monolayers growing on permeable supports were used in order to ensure the apical location of measured Cl- channels. The ORDIC needed to be activated by excision and/or depolarization, and was found in both cAMP-stimulated and non-stimulated cells. Both 5-nitro-2-(3-phenylpropylamino)-benzoate (NPPB) and 4,4'-dinitro-2,2'-stilbenedisulphonate (DNDS) induced fast flickery-type blocks of the ORDIC at low, micromolar blocker concentrations and were used as a probe for ODIC. However, these substances were ineffective in blocking transepithelial forskolin-induced Cl- secretion of monolayers in Ussing chambers. No inhibitory effect at all was detected for DNDS up to 1 mmol/l. NPPB blocked the ORDIC at low concentrations (IC50 = 0.5 +/- 0.3 mumol/l) by reducing its open probability, but NPPB did not block forskolin-induced Cl- secretion unless high concentrations were used (IC50 = 240 +/- 10 mumol/l). In order to exclude effects of NPPB other than on the apical Cl- channel, transepithelial measurements were performed in basolaterally amphotericin-permeabilized, forskolin-stimulated preparations, and a serosal-to-mucosal Cl- gradient was applied as a driving force. Under these conditions, NPPB's inhibitory effects were also very small. Noise analysis of this gradient-driven Cl- current showed a very-low-frequency Lorentzian noise component (fc = 1.4 +/- 0.2 Hz), which was not compatible with Lorentzians predicted from single-channel gating of ORDIC.(ABSTRACT TRUNCATED AT 250 WORDS)


Cardiac gap junctions: three distinct single channel conductances and their modulation by phosphorylating treatments. The effects of an increase in intracellular cyclic GMP (cGMP)-concentration on gap junctional current (Ij) were studied in cultured neonatal rat heart cells using both the whole-cell and perforated patch voltage-clamp method. In whole-cell measurements, exposure to 8-bromo-cGMP or carbachol reduced Ij. With the perforated patch technique, on the other hand, Ij was not affected by either 8-bromo-cGMP or carbachol. Addition of alkaline phosphatase prevented the carbachol-induced decrease in Ij in whole-cell measurements. Reduction of Ij in well-coupled cell pairs by application of heptanol allowed us to study the effects of these substances on the single gap junction channel level. We found that cGMP-treatment shifts the single channel conductance (gamma j) from 43 to 21 pS in whole-cell measurements and that intracellular addition of phosphatase prevents this shift. In contrast, intracellular phosphatase-treatment itself shifts gamma j to 70 pS. Our results indicate that Cx43-gap junction channels may exhibit three conductance levels (21 pS, 40-45 pS and 70 pS), depending on the phosphorylation state of the protein.


Heterologous expression of the human potassium channel Kv2.1 in clonal mammalian cells by direct cytoplasmic microinjection of cRNA. The cloned human delayed rectifying K+ channel Kv2.1 (drk1) was expressed in clonal mouse fibroblasts (L-cells) and rat basophilic leukemia cells (RBL-1) by direct cytoplasmic microinjection of complementary RNA (cRNA). Within six hours, cells microinjected with Kv2.1 cRNA expressed a large sustained outward current as determined from whole-cell patch-clamp recordings. Nearly 100% of cells injected with cRNA expressed outward current. Current density was 30-70 pA/pF when measured at a potential of +50 mV. Steady-state activation and inactivation parameters for Kv2.1 were similar when expressed in either L-cells or RBL-1 cells. These results are the first to demonstrate that functional ion channel proteins can be expressed in mammalian clonal cell lines by direct cytoplasmic microinjection of cRNA.


Mucoadhesion of copolymers and mixtures containing polyacrylic acid. Water-soluble polymers were synthesized from dextran and polyacrylic acid and their ocular mucoadhesion was evaluated. One series had polyacrylic acid grafted onto the polysaccharide backbone of dextran, and another series had dextran grafted onto the polyacrylic acid backbone. Mucoadhesion of these copolymers was investigated using a tensile apparatus and compared with that of polyacrylic acid/dextran mixtures prepared in different proportions. Whatever the copolymer structure, no synergistic effects were seen and mucoadhesion was not markedly increased compared to dextran. The adhesion of copolymers was the same as that of mixtures having a similar polyacrylic acid content and was always less than that of polyacrylic acid alone. Formation of an interpolymer complex occurred at concentrations up to 60% polyacrylic acid, and only above this value did bioadhesion increase above that of dextran. When this complex was dissociated by neutralization of the carboxyl groups of polyacrylic acid, the mucoadhesion of the copolymers and the mixtures was improved. These experiments demonstrated that copolymers and mixtures of dextran and polyacrylic acid did not produce polymers with improved ocular mucoadhesion.


[Endometriosis of the large intestine].

[Endometriosis of the large intestine]. Two cases of large intestine endometriosis are presented. The disease was diagnosed during histological examination of samples taken during surgery. Clinically one case was diagnosed as Crohn's disease, while the second as cancer of the large intestine. The authors suggest, that an extent of surgery for, tumours of the large intestine should be carefully planned, specially if the tissue specimen was not examined histologically earlier.


Folate deficiency, biopterin and monoamine metabolism in depression. Seven (21%) of 34 patients with a severe DSM-III diagnosis of major depression had red-cell folate levels below 150 ng/ml. This subgroup with folate deficiency had significantly lower CSF 5-hydroxyindoleacetic acid (5HIAA) compared to neurological controls. For all depressed patients red-cell folate was significantly correlated with CSF 5HIAA and homovanillic acid (HVA). CSF tetrahydrobiopterin (BH4) was significantly correlated with CSF 5HIAA and HVA and red-cell folate. Our observations provide further evidence of the links between folate, biopterin and monoamine metabolism in depression.


Sulfur dioxide-induced bronchoconstriction via ruthenium red-sensitive activation of sensory nerves. The mechanism of sulfur dioxide-induced bronchoconstriction was studied using isolated perfused and ventilated guinea-pig lungs. They were exposed to sulfur dioxide after pretreatment with different compounds, either via the pulmonary artery or via the air passages. Neither the cyclooxygenase inhibitor indomethacin (30 microM) nor the H1-receptor antagonist diphenhydramine (15 microM), given via the perfusate, attenuated the sulfur dioxide-induced bronchoconstriction. Furthermore, sulfur dioxide exposure did not cause a release of either thromboxane or histamine into the perfusate. In experiments with atropine equivocal results were obtained with regard to protection against sulfur dioxide-evoked bronchoconstriction. Intratracheal instillation of the local anesthetic agent lidocaine (1 mg/50 microliters) markedly reduced the sulfur dioxide-induced bronchoconstriction. Also, ruthenium red (10 microM), an agent with calcium entry-blocking properties and an inhibitor of capsaicin-induced bronchoconstriction, was able to inhibit the effect of sulfur dioxide. The sulfur dioxide-induced bronchoconstriction was associated with release of calcitonin gene-related peptide, a sensory neuropeptide. The effect of sulfur dioxide was also inhibited by a Ca(2+)-free buffer plus EGTA. These results suggest that sulfur dioxide-induced bronchoconstriction in the guinea-pig lung is the result of a local effect on sensory nerves (C-fiber activation). The mechanism seems to be dependent on the Ca(2+)-dependent release of sensory neuropeptides and to be linked to opening of the cation channel, which is associated with the proposed capsaicin receptor on sensory nerves as revealed by the inhibitory effect of ruthenium red.


[The role of radiotherapy in the early stages of Hodgkin's disease]. The outcome of treatment for a first relapse in early stages (IA and IIA) of Hodgkin's disease after primary radiotherapy was analyzed in 86 patients. They received total nodal radiotherapy (TNR) as the primary treatment. Survival was used as the major endpoint. Median follow-up was 13.1 years. Duration of first complete remission was 60% for patients in stage IA and 39% for patients in stage IIA (p < .01). At 10-years, the survival for patients in stage IA was 78% and only 55% for patients in stage IIA (p < .01). A risk factor analysis showed that the presence of stage IIA and bulky disease (adenopathy > 7 cm) were associated with a worse prognosis. We believe that the use of TNR as initial treatment in early stages of Hodgkin's disease should be considered in patients in stage IA and without bulky disease. Patients in stage IIA and risk factors, such as bulky disease, should be treated with more aggressive therapeutic regimens.


Follicular gastritis and its association with Helicobacter pylori infection. Fifty endoscopic biopsies with follicular gastritis (FG) were reviewed to define the frequency of association of FG and Helicobacter pylori (H pylori) infection. All biopsies were studied in sections stained with hematoxylin and eosin and no special techniques were employed. In forty-two out of the fifty cases (84%) H pylori was documented and most of the gastritis showed activity. There was no correlation between the quantity of follicles and the number of bacilli; some biopsies with few follicles showed many microorganisms and others with many follicles showed only a few. There was also no correlation between the presence of the follicles and the distribution of Helicobacter: in some biopsies the microorganisms were found in the tissue fragments with hyperplastic follicles but in others, it was observed in fragments without lymphoid follicles. The high frequency of association between FG and H pylori suggests that this microorganism has some antigenic properties that condition lymphoid tissue hyperplasia in gastric mucosa. It is concluded that the diagnosis of follicular gastritis should be considered an important finding and its presence should lead to a careful search for H pylori. In most cases the microorganism can be identified in routine sections using only hematoxylin and eosin stain.


Response of lipoprotein lipase to calorie intake in streptozotocin-induced diabetic rats. The mechanism regulating lipoprotein lipase (LPL) expression in adipose tissue was examined in rats in the conditions of different calorie intakes with and without streptozotocin-induced (STZ-) diabetes. The LPL activity released from adipose tissue was greater with the higher calorie intake (20 g of normal chow diet per day) than with the lower calorie intake (13 g of normal chow diet per day), and was greater in normal rats than in STZ-diabetic rats. The LPL activity was proportional to the serum insulin level in all conditions. Dot-blot analysis showed that the amount of LPL mRNA in adipose tissue was increased by the higher calorie diet and that the increase was less in the diabetic state. Expression of mRNA was also nearly parallel with the serum insulin level. LPL activity released from the heart was not affected by either the calorie intake or the diabetic state. These results suggest that the mechanisms of LPL expression in adipose tissue and the heart are different, and that LPL expression in adipose tissue was closely dependent on the insulin level.


Primary B cell lymphoma of the rectum in a patient coinfected with HIV-1 and HTLV-I. This report describes a clinical case of a large cell, immunoblastic plasmacytoid malignant B-cell lymphoma of the rectum in an AIDS patient coinfected with HTLV-I. The malignant cells showed clonal genetic rearrangement of the HC (JH) and LCK genes. Infection by EBV was demonstrated serologically and with slot blots using genomic DNA of the cancer cells. Southern blot analysis with DNA extracted from the lymphoma cells were negative for HTLV-I. The patient received seven cycles of VACO-B which induced complete but transient clinical remission of the tumor. The final outcome of the patient is unknown.


[Non-Hodgkin's lymphoma secondary to Hodgkin's disease treated with chemo- and radiotherapy. Report of a case]. In 18 years of experience in the use of combined chemotherapy in Hodgkin's disease at the Instituto Nacional de la Nutrición Salvador Zubirán, the first case of non-Hodgkin's lymphoma secondary to Hodgkin's disease was identified. The patient was a 23 year old male who initially developed a nodular sclerosis type of Hodgkin's disease. Three years later, the biopsies showed lymphocyte predominance type of Hodgkin's disease. Finally, one year later, the patient developed a diffuse small cleaved cell lymphoma. Non-Hodgkin's lymphoma occurring in patients treated with combined chemotherapy and radiotherapy after Hodgkin's disease is a rare complication. We believe that the genesis of a second neoplasm in these cases may be due to both disturbances in the cellular immunity intrinsic to Hodgkin's disease and the treatment with combined chemotherapy and radiotherapy.


Influence of agents affecting monooxygenase activity on taurolithocholic acid-induced cholestasis. In rats, pretreatment with certain ketones results in enhanced taurolithocholic acid (TLCA)-induced reduction in bile flow, whereas pretreatment with inhibitors of protein synthesis diminishes the effect on bile flow of cholestatic regimens. In the present study, the possible role of cytochrome P-450 in the ketone potentiation phenomenon was investigated. Male rats were pretreated with inducers or inhibitors of hepatic cytochrome P-450 and the impact of these pretreatments on TLCA-induced cholestasis assessed. Phenobarbital, 3-methylcholanthrene, chlordecone or mirex were used as inducers, and SKF 525-A, piperonyl butoxide, or cobaltous chloride as inhibitors of monooxygenase activity. Phenobarbital and 3-methylcholanthrene pretreatment enhanced TLCA-induced reduction of bile flow, while mirex and chlordecone were without effect. The three inhibitors of monooxygenase activity did not diminish TLCA-induced cholestasis. Instead, piperonyl butoxide and cobaltous chloride appeared to enhance the action of TLCA. Consequently, an increase in cytochrome P-450 (or specific isozymes) as a common denominator in the potentiation phenomenon appears unlikely. While hepatic proteins may play an important role in the potentiation of TLCA-induced cholestasis following pretreatment with ketones, the pattern of potentiation after pretreatment of rats with different inducers or inhibitors of cytochrome P-450 does not appear to implicate this family of proteins.


Fetal mouse salivary glands and applications for determining teratogenic mechanisms in vitro. Culture systems offer advantages for studying the actions of chemicals on mechanisms of development. Growth, [3H]thymidine incorporation, and 14C-amino acid incorporation were measured to determine culture conditions and the response of glands to three chemicals. Eagle's MEM supported the best growth and the best time for double isotope presence was the second 24 h of culture. Cyclamate had no effect on growth or isotope incorporation but cycloheximide disturbed 14C more than 3H. 5-Azacytidine was toxic but the incorporation of both isotopes exhibited the same pattern.


[Diagnostic value of the analysis of alpha fetoprotein levels in malignant neoplasms of the digestive system]. The concentration of alpha-fetoprotein (AFP) in serum was determined in 58 patients (35 males and 23 females) aged from 38 to 87 years treated surgically for malignant tumours of the digestive tract, including colonic carcinoma in 30, gastric carcinoma in 11, pancreatic carcinoma in 10 and oesophageal carcinoma in 7 cases. In 33 patients the tumour was disseminated (into the liver in 22 cases). On the ground of AFP concentration determinations in 40 patients (19 males and 21 females) aged 22 to 80 years operated on for non-neoplastic abdominal diseases the upper normal range was accepted as 9.42 ng/ml. Raised AFP concentration was found in only patient with advanced pancreatic carcinoma and multiple metastases to the liver and lymph nodes. The study showed that serum AFP level in cases of digestive tract malignancies is of limited diagnostic value.


[Spontaneous intraperitoneal rupture of asymptomatic hydronephrosis]. A 63-year-old patient had spontaneous rupture of asymptomatic hydronephrosis+ into the peritoneal cavity as result of cast renal calculus. During the operation similar changes in the right kidney were found and, in view of this, palliative operation was done with removal of concrements and sparing of both pathologically changed kidneys. After the operation the kidneys resumed their function.


[Non-Hodgkin's lymphomas: principles and application of the Kiel classification]. In the Kiel classification malignant non-Hodgkin's lymphomas (NHL) are defined essentially according to their constituent cells, based on their morphologically and immunologically defined normal equivalents. For pragmatic reasons they are also divided into low and high grade malignant lymphomas. The most important condition for applying the classification is technical excellence, especially in embedding. The usual criteria of malignancy are only partially applicable to the division into reactive and malignant lymph node diseases. There are borderline cases between nonneoplastic and neoplastic lymph node diseases that cannot presently be distinguished with certainty with any method--including immunohistochemistry and molecular and classical genetics. Thus the gold standard of lymphoma diagnostics remains the subtle morphological investigation. In doubtful cases there should be close feedback between pathologists and clinicians.


[Histological classification of malignant non-Hodgkin's lymphomas and patient survival: the Kiel classification versus the working formulation]. In 163 out of 251 histologically classified malignant Non-Hodgkin's lymphomas, a comparison was made of the patient survival with respect to both histological type and malignant grade according to the Kiel Classification (KC) and the three prognostic groups of the Working Formulation (WF). As expected, the survival rate of 94 low-grade malignant lymphoma cases (KC) was significantly better than that of 69 high-grade cases (p < 0.0001). Similar results were found both for 46 low grade cases (WF) in comparison to 50 high grade cases (p < 0.001) and for 67 intermediate grade cases (WF) compared with the 50 high grade cases (p < 0.05). The survival rates of low and intermediate grade cases (WF), however, showed no statistically significant difference. The low- and high-grade malignant lymphoma entities of KC, which together constitute the intermediate grade of WF, differed significantly with respect to patient survival (p < 0.05). Therefore, it appears that an intermediate grade is not essential in the KC.


[Angioimmunoblastic lymphadenopathy (AILD): histology and survival time]. In order to identify histological and immunohistochemical criteria of prognostic value in AILD 40 lymph nodes with typical and 15 cases with incomplete features were semiquantitatively analyzed. Their expression were correlated with survival data of all patients. Significant prognostic value could be detected for following parameters: mitoses, immunoblasts, CD 30-positive blasts, multinuclear tumor cells and eosinophilic granulocytes. However residual lymph node structures, venules, PAS-positive material, and reticulum cells did not correlate with survival data. The short median survival time does not justify AILD grouping as low grade malignant lymphoma.


[T-cell rich B-cell lymphoma associated with hemophagocytic syndrome]. Report of a T-cell rich B-cell lymphoma (TCRBCL) in a 43 years old man with an associated haemophagocytic syndrome (HS). At presentation the haemophagocytic cells involved the same organs as the lymphoma, i.e. spleen, liver, abdominal lymph nodes and bone marrow. As supportive measure to alleviate chemotherapy-induced granulocytopenia the cytokine granulocyte-macrophage colony-stimulating factor (GM-CSF) was given. After an initial improvement of the blood granulocyte count pancytopenia developed again, resulting in fatal sepsis. Autopsy demonstrated massive proliferation of macrophages in the bone marrow with haemophagocytosis as morphological correlation to the pancytopenia. The observation that exogenous GM-CSF enhanced the preexistent HS primarily reactive to the TCRBCL raises the question if endogenous GM-CSF may play a role in triggering a HS. The observed association of TCRBCL and HS has not been reported so far.


[Lymphoid follicles of the human large bowel mucosa: structure and function]. Little is known about morphology and function of human solitary lymphoid follicles (LF), a component of the gut-associated lymphoid tissue. We have studied 156 LF in situ from 10 colorectal resection specimens by use of serial frozen sections and immunohistochemistry (APAAP technique) and found 8 to 10 LF per cm2, i.e. 11,000 to 14,000 LF in the whole organ. Two types were identified: (1) One type, located in the colon, displayed a pit-like follicle-associated epithelium (FAE). A large part of this LF extended into the submucosa. (2) The other type was noticed mainly in the tunica mucosa of the rectum and had a flat FAE. All LF exhibited a rather constant structure. The main elements were FAE, dome region, B-lymphocyte region with surrounding T-lymphocyte area including high endothelial venules, and a lymph sinus that delimited the LF against the submucosa. One out of five LF contained a germinal center. Marked differences were found between the immunological effector cell population of the LF and that of the lamina propria. These observations denote (1) a striking compartmentation of these cells in the gut mucosa; (2) a marked similarity of the immunomorphology of LF to that of Peyer patches; (3) a functional analogy: The LF belong to a physically discrete compartment that constitutes the afferent limb of the local immune system, as the Peyer patch does. The lymphomonocytic elements of the lamina propria belong to the efferent limb. Results of in vitro studies, generally based on a mixture of cells from both compartments, may thus not reflect the conditions found in vivo.


[Morphological changes in the lymphatic system of children with hereditary immunologic deficiency syndromes]. The morphology of lymphatic tissues in 43 autopsy cases of children with inherited immunodeficiency states were analysed. Among the more common diseases, such as Di-George-syndrome, CID-patients, congenital agammaglobulinemia Bruton, CVID, selective IG-A deficiency, Wiskott-Aldrich-syndrome, tissue sections of very rare conditions associated with immunodeficiency, e.g. fetopathia diabetica and leprechaunismus, were investigated by routine and immunohistochemical stainings. Clinical history and laboratory data, augmented by the characteristic pathomorphology of lymphatic tissue sections, will establish or at least suggest a definite diagnosis. Since true thymic dysplasia is very rare (or even non-existent) in the human, this term should be abandoned. Severe thymic tissue alterations in SCID-patients, occur secondary to enzyme defects in lymphatic cells. If patients are successfully treated by bone marrow transplantation, the thymus will subsequently develop into a functionally normal organ.


[Value of "non-specific" lymphoid infiltrates in bone marrow in high grade malignant peripheral non-Hodgkin's lymphomas]. We studied iliac crest biopsies of 120 patients with extramedullary high-grade Non-Hodgkin's lymphomas (NHL). The bone marrow of 69 patients contained foci of small lymphoid cells, which cytologically differed significantly from the extramedullary NHL and which we termed abnormal lymphoid infiltrates (ALI). The ALIs in 14 out of 25 cases immunohistochemically investigated in more detail were made up of small CD3+ cells optionally intermingled with a minority of CD20+ cells of small to intermediate size. In 10 patients, however, the ALIs satisfied the criteria of a low-grade NHL. In the vicinity of the extramedullary high-grade lymphoma, residues of the corresponding low-grade NHL were identified in up to 7 of 10 cases. We conclude that bone marrow ALIs associated with extramedullary high-grade NHL exhibit at least in part the criteria of a systemic clonal expansion of premalignant lymphoid cells or low-grade NHLs respectively, which gives rise to the final evolution of the extramedullary high-grade NHL.


Extranodal lymphomas: the MALT concept.

Extranodal lymphomas: the MALT concept. Extranodal lymphomas account for as many as 40% of non-Hodgkin's lymphomas and most arise in the gastro-intestinal tract which is a major lymphoid organ in its own right. Gastrointestinal (gut) associated lymphoid tissue (GALT) and that of other mucosae (MALT), differs both structurally and functionally from nodal lymphoid tissue and low grade B cell lymphomas arising in the gastrointestinal tract and other mucosae have been found to recapitulate the structure and cytological features of MALT. Moreover, these lymphomas are clinically indolent which could be explained by the restricted homing patterns of MALT. Curiously, however, most MALT lymphomas arise in sites, such as the stomach, where MALT is not normally present. Several chronic inflammatory conditions, most of which have an autoimmune component, result in the acquisition of MALT-like lymphoid tissue, and have been identified as necessary precursors for the development of MALT lymphoma. These include Helicobacter pylori induced chronic gastritis, Sjögren's syndrome and Hashimoto's thyroiditis. Histologically, low grade MALT lymphomas are characterized by centrocyte-like (CCL) B cells which surround reactive follicles and form characteristic lympho-epithelial lesions with adjacent epithelium; they frequently show plasma cell differentiation. Specific colonization of reactive follicles by CCL cells often occurs and transformation into a high grade lymphoma may occur. The phenotype of MALT lymphoma CCL-cells is similar to that of marginal zone B cells; no characteristic genotypic features have yet been identified. When lymph nodes are involved by MALT lymphoma their appearance may be indistinguishable from those of so-called monocytid B cell lymphoma, a primary lymph node tumour which, unlike MALT lymphoma, shares the clinical features of other low grade nodal B cell lymphomas.


[Malignant lymphomas of soft tissues].

[Malignant lymphomas of soft tissues]. Among annually 1000 consultation cases of soft tissue tumors, minimally 1.2% to maximally 2% malignant lymphomas could be identified, which presented as (primary) soft tissues tumor. Thus malignant lymphoma as soft tissue tumor is rare, however, it has to be considered in differential diagnosis not only of cellular round cell sarcoma, but also with undifferentiated carcinomas (large cell Ki-1 lymphomas) and various myxoid spindle cell sarcomas (sarcomatoid lymphoma). Decisive in differential diagnosis were decorations with pan-leucocyte antibody, as well as, B- and T-cell markers. All cases turned out to be non-Hodgkin lymphomas, the majority of B-cell type, with large cells which qualified as centroblasts (according to Kiel classification). Similar findings, predominance of B-cell non-Hodgkin lymphomas with large cells, were reported in the few series published of malignant lymphomas as soft tissue tumors. Remarkable were relatively good prognosis with "highly malignant" morphology and preference for involvement of soft tissue even after dissemination. Future studies are requested to shed light on possible specific cellular findings as to phenotype and genotype in malignant lymphoma presenting as soft tissue tumors, as already had been done with subcutaneous T-cell lymphoma and primary lymphoma of the bone.


[Non-Hodgkin's lymphoma with primary osseous manifestation, from the files of the Bone Tumor Registry of Westphalia]. 30 cases of non-Hodgkin-lymphoma with primary bone manifestation were selected from the files of the Bone Tumor Registry of Westfalia from 1975 until 1992. Clinical data and radiologic aspects were evaluated. 60% of the lesions were localized within the long bones (femur 10, humerus 6, tibia 2). The lymphomas were classified based on paraffin-embedded material in combination with immunohistochemical findings according to the updated Kiel-classification. 29 B-cell lymphomas and one T-cell lymphoma of medium-sized pleomorphic type were found. 5 B-cell lymphomas were of low and 23 of high malignancy. Almost 50% of the tumors were of centroblastic type. The Kiel-classification was not applicable for one lymphoma, 3 others could not be subclassified because of shrinking artefacts. Prognosis in patients with localized disease (9 cases) was favorable, whereas only 25% of patients with generalized disease (12/cases) survived for 3 years or longer.


[Proliferating cells in Hodgkin's disease]. We have studied the proliferation fraction of Hodgkin- and Reed-Sternberg (HRS) cells and L&H cells in paraffin sections of 15 cases of classical Hodgkin's disease (HD) (12 nodular sclerosis [NS], 3 mixed cellularity [MC]) and 8 cases of nodular lymphocyte predominant Hodgkin's disease (NLPHD) using an antibody to proliferating cell nuclear antigen (PCNA). By double staining with anti-PCNA and antibodies to B- and T-cells we also determined the growth fraction and immunophenotype of the background lymphocytes in each case. In classical HD 45.3% of HRS cells, and in NLPHD 76.9% of L&H cells were in cycle. In both classical HD and NLPHD the majority of proliferating cells in the background were T-cells with 57.8% respectively 68.5%, whereas only a few B-cells were proliferating in each type of HD.


[Which are the proliferating cells in Hodgkin's disease?]. This investigation characterizes the proliferating cells in Hodgkin's disease. We used the antibody PC 10 which reacts with the proliferating cell nuclear antigen (PCNA) and works on paraffin sections in combination with B- and T-cell markers in a double-staining technique. In all 38 cases of Hodgkin's disease (lymphocyte predominant type n = 10, nodular sclerosis type n = 10, mixed cellularity type n = 10, lymphocyte depletion type n = 8) a high percentage of the Hodgkin and Sternberg-Reed cells (95%-97%) expressed PCNA. There was no statistical significance between the different types. In contrast, only a small amount of the reactive lymphocytes (2.8%-3.4%) demonstrated positivity for PCNA in the four types of Hodgkin's disease. Nearly all of these lymphocytes were T-lymphocytes.


[Borderline between Hodgkin and non-Hodgkin lymphomas with unfavorable clinical course: a clinical, histological and immunohistochemical analysis of 33 cases within the German Hodgkin Lymphoma Study]. Reevaluation of diagnostic biopsies from 502 patients who entered the German Hodgkin Therapy trial was performed by a panel of four pathologists. Classification revealed 90% of unambiguous Hodgkin-lymphomas (HL), 1.6% of Non-Hodgkin-lymphomas (NHL) and 8.4% of cases difficult to evaluate, reflecting to the well-known problem of the border between these 2 groups of lymphoma. As these cases had the worst prognosis, a second attempt of reclassification, including immunohistochemical studies, was made, resulting in final classifying of 25% of these cases as NHL, 50% as HL, and 25% as further unclassifiable. The most common differential diagnostic problem was separating pleomorphic nodular sclerosing HL from large cell NHL's and HL with rather few Hodgkin- or Reed-Sternberg-cells from Lennerts lymphoma or angioimmunoblastic lymphadenopathy. Immunohistochemistry was helpful for the differential diagnostic decisions in these individual cases. A very high percentage of these problem cases had initially entered the trial as lymphocyte depleted HL, and the large majority of deaths came from the large cell NHL group.


[Immunohistochemical in situ demonstration of cytokines in Hodgkin and non-Hodgkin lymphoma]. Primary biopsies from 149 patients with malignant lymphomas were examined by histological and immunohistochemical techniques. Twenty eight cases were classified as Hodgkin's disease and 121 as non-Hodgkin's lymphomas. The immunohistochemical distribution of cytokine expression (Il-1 alpha, Il-1 beta, Il-6 and TNF-alpha) was demonstrated in neoplastic cells and in tumor-associated macrophages (TAM). Neoplastic cells showed mostly weak positivity for TNF-alpha in 40% of Hodgkin's disease and in 20% of T cell lymphoma cases. Two groups of malignant lymphomas were established which differed in the numbers of cytokine expressing TAM. The first group consisted of malignant lymphomas which contained large quantities of cytokine-possessing TAM. In the second group significantly lower frequencies of cytokine expressing TAM were found. In both groups high and low grade malignant lymphomas were encountered. There was a significantly positive correlation between the number of Il-6 possessing TAM and the proliferation of lymphoma cells in only the non-Hodgkin's lymphomas. Our results suggest a paracrine tumor growth stimulating mechanism which is created by a self perpetuating cytokine production loop. A supposed cytokine produced by neoplastic cells dependent from their proliferative activity may induce Il-6 secretion by TAM. Il-6 in turn may stimulate the proliferation of the lymphoma cells without maturation thus leading to a self-sustaining growth.


[Bcl-2 in potentials precursors of nodular paragranuloma and its dedifferentiated variant (large cell B-lymphoma)]. We have investigated seven cases of large cell lymphomas (LCL) developing simultaneously or metachronously to nodular lymphocyte-predominant Hodgkin's disease (nodular paragranuloma, NP) for the presence of EBV and the chromosomal translocation t(14;18) by use of the polymerase chain reaction (PCR). The expression of the bcl-2 oncogene product in these cases and in five cases of progressive transformation of germinal centres as a potential precursor of NP was detected immunohistochemically with the monoclonal antibodies bcl-2-100 and bcl-2-124. All cases investigated were negative for EBV genomic material. The chromosomal translocation t(14;18) was also absent. Expression of the bcl-2 oncogene could be detected only in one case of nodular paragranuloma and in an unrelated case of LCL. Hence, LCL developing out of NP differ from other germinal center derived high-grade lymphomas.


[Influence of Epstein-Barr virus genome on patient survival in Hodgkin's disease]. In the literature EBV is considered a possible etiologic factor for Hodgkin's disease (HD). We investigated 187 cases of HD for the presence of Epstein Barr virus using the polymerase chain reaction (PCR) technique on formalin fixed, paraffin embedded lymph node tissue to clarify the clinical importance of the incidence of this genome. The 187 cases included all subtypes. 66 cases (35.2%) were positive for EBV DNA. The statistical analysis of follow-up data from 130 patients revealed no influence of EBV DNA on survival time. In our investigation detection of EBV DNA by PCR showed no prognostic relevance for patients with HD.


[Nodular paragranuloma and Epstein-Barr virus: frequency of EBV DNA and clinical relevance]. Studies demonstrating Epstein-Barr virus (EBV) DNA in Hodgkin's disease (HD) provide little information about the EBV-status in the lymphocyte predominant subtype (nodular paragranuloma) which is due to the small number of cases investigated. Therefore we studied 99 typical cases of nodular paragranuloma for the presence of EBV-DNA using the polymerase chain reaction (PCR) technique. Genomic DNA was amplifiable in 71 cases; 29 cases (= 40%) were positive for EBV-DNA (EBNA-1). In situ hybridization revealed EBV-RNA (EBER-1) in L&H cells and in a few lymphocytes. PCR results were correlated to clinical follow-up data and did not show any statistically significant relationship between EBV positivity and survival of the patients.


[Demonstration of Epstein-Barr virus DNA and determination of immunoglobulin and T-cell receptor gene rearrangerments in diagnostic lymph node biopsies from patients with Hodgkin's disease]. Lymph node biopsies of 52 patients with Hodgkin's disease were analyzed by Southern blot hybridization for the presence of monoclonal rearrangements of immunoglobulin and T cell receptor genes. The same tissues were tested for Epstein-Barr virus DNA by the polymerase chain reaction using four different sets of primers. Monoclonal rearrangements were identified in only four tumors, whereas Epstein-Barr virus was present in 79% of biopsies. A correlation between the degree of infiltration by Reed-Sterberg cells, clonality and the presence of Epstein-Barr virus could not be found. These results are in agreement with similar studies reported in the literature. The nature of the malignant cell in Hodgkin's disease and the role of Epstein-Barr virus in the etiology of this tumor remains to be established.


[Opportunistic malignant lymphomas in SIV infected primates--a model for Epstein-Barr virus associated lymphomas in AIDS]. In a series of 33 cynomolgus monkeys (Macaca fascicularis) experimentally infected with Simian Immunodeficiency virus (SIV), strain smm3, 13 animals developed malignant Non-Hodgkin lymphomas. These lymphomas presented with unusual primary manifestations like in the orbita, testes, and brain. The morphological features and immunophenotyping identified the tumors as high malignant B-cell lymphomas. In all tumors as well as in tumor-derived cell lines a cynomolgus B-lymphotropic herpes virus (CBLV) with structural homogeneity to the Epstein-Barr virus (EBV) could be demonstrated by Southern blotting with EBV-specific probes. The lymphoma cells also expressed CBLV-associated nuclear antigens involved in B-cell transformation crossreacting with EBNA-specific human sera and monoclonal antibodies. Ig-gene rearrangement studies revealed clonal populations, however, no translocations of the c-myc oncogene could be detected. The lymphomas developing with high frequency in SIV-induced immunodeficiency resemble a major subtype of human EBV-associated AIDS lymphomas. This animal model can therefore be used to further elucidate interactions of HIV and EBV in AIDS-related lymphomagenesis.


[EBV in malignant lymphomas].

[EBV in malignant lymphomas]. PCR and in-situ-Hybridization were used to detect EBV-DNA within Hodgkin- and Non-Hodgkin-Lymphomas. By the use of primers for the Bam H1 W fragment we could show EBV-DNA to be associated with 45% Hodgkin- and 25% T-Lymphomas, whereas we could not find EBV-DNA within B-Lymphomas. In about one third of the PCR-positive cases we could localize EBV-DNA mostly in the tumor cell nuclei by in-situ-hybridization.


[Detection of Epstein-Barr virus genomes in various entities of low and high grade T-cell lymphomas]. 72 T-cell lymphomas were analyzed for the presence of Epstein-Barr virus DNA using Southern or dot blot hybridization. EBV DNA was found in 25 peripheral T-cell lymphomas and in none of 6 T-lymphoblastic tumors. A high prevalence of EBV was detected in AILD type, Lennert's, pleomorphic medium and large cell nodal lymphomas and in upper aerodigestive tract lymphoma biopsies. Clonotypic analysis revealed monoclonal as well as oligoclonal viral populations. The possible influence of EBV in lymphomagenesis, the impact of virus-mediated interactions in the B- and T-cell system and factors involving site of tumor development are discussed.


[Heterogeneous Epstein-Barr virus infection patterns in peripheral T cell lymphoma of the angioimmunoblastic lymphadenopathy type]. 32 cases of T cell lymphoma of angioimmunoblastic lymphadenopathy type (AILD-TCL) were investigated for their association with Epstein-Barr virus (EBV). Polymerase chain reaction (PCR) for detection of EBV-DNA and in situ hybridization for EBV-encoded small nuclear RNAs (EBER) produced almost identical results, showing that all but one of AILD-TCL cases contained EBV genomes. Three distinctive patterns of EBV infection were observed after immunophenotypical characterization of EBER positive cells: 1. predominant infection of B-immunoblasts (26% of the cases), 2. predominant infection of neoplastic T cells (42% of the cases) and 3. infection of few small lymphocytes (32% of the cases). EBV-encoded latent membrane protein was frequently detectable in cases exhibiting patterns 1 and 2. These findings suggest that, in AILD-TCL patients B cells and especially T cells are highly susceptible to a persistent EBV infection which may lead to a growth advantage of infected cells.


[Classification and virus expression of primary cerebral lymphomas]. Fourty-three primary cerebral lymphomas (PCL) were histologically classified and examined for genome expression of Epstein Barr Virus (EBV) and human herpes virus 6 (HHV6) using dot blotting, polymerase chain reaction, and Southern blotting. Only 20 tumors (16 high grade and 4 low grade lymphomas) could be suitably placed into a category of the Updated Kiel Classification, whereas the non-classified 23 tumors were highly malignant B-lymphomas and referred to as small-cell (SC) or large-cell (LC) blastic PCL. Most of the LC PCL showed a tumor-like infiltration pattern with high cellular density and little remaining parenchyma, whereas the SC PCL more often showed an inflammation-like pattern characterized by loose arrangement of tumor cells and marked astrocytic, microglial and T-lymphocytic reaction. EBV genome was found in 3/3 AIDS cases, but in none of 40 immunocompetent cases, while HHV6 was detected in 2 tumors of immunocompetent patients. We conclude that (1) the Updated Kiel Classification is not applicable to a majority of PCL, and (2) EBV and HHV6 do not appear to play a major role in the pathogenesis of PCL in immunocompetent subjects.


[EBV-lymphadenitis: diagnostic possibilities using immunohistochemistry and in situ hybridization]. EBV infections were studied in paraffin embedded lymph node specimens (n = 20) on DNA, protein, and histological level. The lymph nodes were obtained from 20 patients all testing positive for EBV serologically. The EBV DNA was detected by non radioactive in-situ-hybridisation using the BamHI W fragment of the virus. The EBV latent membrane protein was detected immunohistochemically using the LMP antibody (DAKO). Infected cells were characterized by monoclonal B cell antibodies. By in-situ-hybridization we found positive signals for EBV in all specimens. In contrast, no LMP was detectable immunohistochemically in 2/20 lymph nodes.


[Follicular dendritic cells in extranodal non-Hodgkin's lymphomas]. Extranodal lymphomas of the thyroid (n = 19), kidney (n = 15) and testis (n = 30) were investigated histologically and immunohistochemically using the monoclonal antibody Ki-FDC1P, which recognizes follicular dendritic cells on paraffin sections. Only lymphomas of the thyroid were of MALT-lymphoma type and contained tumor associated abortive follicles of follicular dendritic cells. In kidney and testis, no MALT-Lymphomas were found. Lymphoepithelial lesions, a hallmark of MALT-Lymphomas, occurred not only in thyroid MALT-lymphomas, but also in testicular centroblastic lymphomas (lacking other features of MALT-lymphomas). Therefore, lymphoepithelial lesions are not specific for MALT-lymphomas.


[Sinus lining cells:morphology, function and neoplasia]. Lymph node sinuses consist mainly of sinus lining cells with clear dendritic morphology. Enzyme cytochemical and immune phenotypical analysis classify sinus lining cells as an intermediate cell type linking monocyte/macrophage to follicular dendritic cells, which are accepted immune accessory cells to humoral immune response. Labeling studies indicate sinus lining cells to hematogenous and possible monocytogenous in origin. In functional term sinus lining cells bind and present soluble antigen as the first cell type following antigen pulse. In addition sinus lining cells bind carcinoma cells and may play a role in metastasis. Sinus lining cells give rise to a well defined entity of neoplasia which is proposed to be termed sinus lining cell reticulosarcoma. In this presentation a case report exemplifies such a new entity.


[Morphological and immunohistochemical findings on the frequency of intranuclear immunoglobulin inclusions (Dutcher bodies) in malignant B-cell lymphomas]. 318 cases of 682 malignant B-cell lymphomas reacted positive for cIg. 66 of them showed Dutcher bodies (DB). DB were found in about 22% of plasmacytomas, 17% of immunocytomas, and in 7.5% of follicular lymphomas and polymorphic centroblastomas, respectively. Regarding only the cIg-positive cases, DB occurred in about 27% of immunocytomas, 20% of follicular lymphomas and 18% of polymorphic centroblastomas. A single case of prolymphocytic leukaemia, centrocytoma, monomorphic centroblastoma, and immunoblastoma each showed also DB. Usually, DB-positive plasmacytomas showed kappa, alpha, and J-chains. The remaining lymphomas mostly expressed kappa, my, and J-chains. In conclusion Dutcher bodies can occur with any cIg-producing B-cell lymphoma. They are not limited to immunocytomas.


[Expression of beta 1 integrins in normal B lymphocytes at different stages of development and in B cell neoplasias]. VLA-1 to -6 are cell surface molecules binding to matrix molecules such as collagen, fibronectin, epiligrin, and laminin. In addition, VLA-4 binds to VCAM-1 and ICAM-2, thus mediating intercellular adhesion prerogative for lymphocyte extravasation or "homing". Using frozen tissue of normal lymphoid organs and of 100 morphologically and immunologically typed B cell neoplasias, monoclonal antibodies to all six VLA-alpha subunits and to the common beta 1-chain were applied to serial sections. VLAs were found differentially expressed in cytologically and microtopographically defined B cell subsets [follicular mantle zone cells (MZ), follicular center cells (FC), extrafollicular cells (EF), and plasma cells (PC)] of normal spleen, lymph node, and thymic medulla (which contains an EF compartment). Thus, these cell types, which correspond to discrete stages of B cell development, can also be defined by their VLA status. Acute B lymphoblastic leukemia (ALL) was VLA-1-, 2-, 3 +/-, 4 +/-, 5 +/-, 6-. The VLA-1-, -2 +/-, -3+, -4+, -5+, -6- phenotype of chronic B lymphocytic leukemia (CLL) resembled that of MZ. Hairy cell leukemia (HCL) differed from CLL in its tendency to lack VLA-2, in its consistent lack of VLA-3, and altogether resembled splenic EF in its VLA profile. Mantle zone lymphoma (MZL) consistently expressed VLA-3 and -4 and frequently VLA-5. Nodal follicular center cell lymphomas (FCCL) were VLA-1- and -2- and very rarely expressed VLA-5 and -6. Thus, FCCL although roughly corresponding to FC, tended to aberrantly express VLA-3 and/or VLA-4. Burkitt's lymphoma resembled FCCL but expressed VLA-4 more frequently and at higher levels.(ABSTRACT TRUNCATED AT 250 WORDS)


[Expression of APO-1, a cell surface molecule mediating apoptosis, during normal B cell ontogeny and in B cell tumors. Co-expression and coregulation of APO-1 and ICAM-1 (CD54) in germinal central cells]. APO-1 is a 48kDa transmembrane glycoprotein and belongs to the NGF/TNF receptor family of surface molecules. Cross-linking of APO-1 induces apoptotic cell death in sensitive cells. Here we show that APO-1 is an activation molecule on B cells. It could be induced/enhanced on dense and buoyant tonsillar B cells, respectively, through surface immunoglobulin cross-linking in combination with interleukin-2 or by interferon-gamma together with tumor necrosis factor-alpha. These conditions also increased the amount of intercellular adhesion molecule-1 (ICAM-1; CD54) on these cells. Epstein-Barr virus transformants of peripheral B cells co-expressed APO-1 and CD54 at very high levels. Immunohistologically, APO-1 was detectable at low levels in a subpopulation of follicular center B blasts and, at higher levels, in sinusoidal B cells. APO-1 was undetectable in follicular mantle B cells and plasma cells. Neoplastic B cell essentially mimicked their reactive counterpart with regard to APO-1 and CD54 expression.


[Hodgkin's disease--an entity?].

[Hodgkin's disease--an entity?]. Since 26 years Hodgkins disease is classified according to the Rye classification into 4 types. This classification is based on morphology and has turned out to be clinically relevant. However, sometimes the classification on morphological and immunohistochemical ground can be difficult to put a special case in a defined category of the 4 types. In addition, there seems to be no sharp, or well defined borders between Hodgkin's disease and Non-Hodgkin's lymphomas, especially T-cell lymphomas. Immunophenotyping of small lymphocytes and detection of follicular dendritic cells can demonstrate typical patterns in different types of Hodgkin's disease. In all types of Hodgkin's disease there is the same amount of proliferating small T-cells present. Hodgkin cells are lymphoid cells with B- or T-cell markers. Hodgkin cells of nodular para-granuloma (lymphocyte predominant type of Hodgkin's disease) show m-RNA for one light chain in the cytoplasm which can be visualized by in situ-hybridization. A new technique called "molecular histology" is applied to Hodgkin's disease. This is a single cell PCR of immunostained cells extracted from tissue sections by a micromanipulator. This technique enables us for the first time to demonstrate light chain and heavy chain gene rearrangements in Hodgkin cells of nodular sclerosis and mixed cellularity type. Hodgkin's disease seems to be no single entity but a heterogenous group of B- and possibly T-cell lymphomas. In the B-cell types Hodgkin cells are probably pre-B and B-cells.


[Detection of clonal immunoglobulin rearrangements in paraffin embedded tissues by PCR]. A polymerase chain reaction based method was established using immunoglobulin VH and VK gene rearrangements as markers to detect clonal B cell populations in paraffin embedded sections. Family specific VH and VK primers are used in separate reactions together with the corresponding J primers to amplify rearranged VH and VK genes from genomic DNA. This allows to distinguish clonal from polyclonal B cell populations in most of the cases. The method may be helpful in routine diagnosis of B cell NHL and some morphological and immunohistochemical difficult cases.


[Tumor proliferation, MDR phenotype and tumor associated t-lymphocytes in non-Hodgkin's lymphomas]. In this study we examined the P170-expression (mdr-phenotype) in 42 non-Hodgkin's Lymphomas with variant entities immunohistochemically with the mab JSB1. The mdr-phenotype was related to the tumor proliferation as measured by Ki67-expression and AgNOR numbers. Furthermore the mdr-phenotype was related to the tumor associated T-lymphocytes. The mdr-phenotype showed no relation to histological type and the proliferation of the tumor. There was a positive correlation between the mdr-phenotype and CD2-reactive lymphocytes. There was also a significant positive correlation between CD4-reactive lymphocytes and the mean number of AgNOR's. Possibly P170-expression and proliferation of the tumor cells have a lymphotactic effect on T-lymphocytes. The latter could promote tumor progression by means of paracrine mechanisms.


[B-cells in thymic epithelial tumors: phenotype, distribution and relation to the intramedullary B-cell population of the normal thymus]. Immunohistochemical analysis of 26 thymomas and thymic carcinomas revealed the occurrence of two different intratumoral B-cell populations. High numbers of B-lymphocytes with formation of lymphoid follicles were found in the extra-epithelial perivascular spaces of cortical thymomas and well differentiated thymic carcinomas associated with myasthenia gravis. On the other hand, B-cells within the epithelial meshwork frequently occurred in organoid medullary islands of predominantly cortical and cortical thymomas. In their distribution and phenotype, these cells correspond to the intramedullary B-cell population of the normal thymus, reflecting a specific intratumoral B-cell homing dependent on medullary epithelial differentiation.


[Neurofilament expression in thymic epithelial tumors and anti-axonal autoantibodies in myasthenia gravis: a model for autoimmunity by abnormal T cell selection]. Thymic epithelial tumors from myasthenia gravis (MG) patients and non-neoplastic thymuses were investigated by immunohistochemistry for the expression of neurofilament (NF) epitopes. There was little immunoreactivity confined to the medulla in non-neoplastic thymuses and a faint staining only for a 200 kD NF epitope in medullary and mixed thymomas. In contrast, cortical thymomas and well-differentiated thymic carcinomas expressed epitopes of the 68 kD and 160 kD NF. Demonstrating anti-axonal and anti-NF autoantibodies in thymoma patients we conclude that "false-positive T cell selection" is a mechanism of autoimmunity in paraneoplastic MG.


[Cysts and tumors of the jaw bone].

[Cysts and tumors of the jaw bone]. The new entities of cysts and odontogenic tumors of the second edition of WHO "Histological Typing of Odontogenic Tumors" (Kramer et al., 1992) are presented. The classification is based on tumor behavior. The benign epithelial odontogenic tumors are classified in relation to tooth development. The malignant odontogenic tumors are subdivided in carcinomas, sarcomas and carcinosarcomas, which are very rare. This international classification has the purpose to make rare cases comparable, so that more detailed knowledge of their characteristics can be achieved. Types of bone tumor that also occur in other parts of the skeleton are not discussed here.


[Clinical and prognosis relevance of the Kiel classification of non-Hodgkin lymphomas]. The Kiel classification of non-Hodgkin lymphomas (NHL) identifies distinct entities by morphological and immunological criteria, subdivided into those of low and high grade malignancy and of B- or T-cell subtype. Numerous clinical studies have proven the clinical and prognostic relevance of this classification scheme although the degree of malignancy alone cannot be automatically equated with prognosis. Thus, histological low grade malignancy correlates with favorable response to therapy in all, but with long term survival only in some clearly defined low grade NHL and final cure is achieved in none of them so far. High grade malignancy corresponds to the aggressive spontaneous course of these NHL but is contrasted with the mostly favorable response to therapy and the chance of cure. The immunological T-cell subtype is clearly associated with an inferior prognosis. Additional biological features of NHL, namely chromosomal aberrations and the status of clonality will contribute to a more differentiated view of NHL and will possibly prove to bear prognostic potential.


Homing receptors and lymphocyte migration. Lymphocyte migration and recirculation of lymphocytes between the lymphoid organs and other tissues is thought to be essential for effective immunologic surveillance and dissemination of the immune response. In addition, lymphocyte recirculation may also be important in the segregation of lymphocytes with particular functions in the different lymphoid tissues. Furthermore, insight in the molecular basis of these processes may help us to understand lymphoma spreading and metastatic invasion of carcinoma cells.


[Malignant lymphomas in spleen--morphology and microenvironment]. The different entities of malignant lymphomas in the spleen exhibit characteristic stage-dependent infiltration patterns which, in conjunction with cytologic findings, may be employed for diagnostic purposes. These infiltration patterns result from complex interactions between neoplastic and non-neoplastic splenic cell populations which are only incompletely understood. These interactions are governed by intrinsic properties of the involved cell populations, e.g. surface receptors, proliferation activity, cytokine production, immunocompetence etc., as well as by extrinsic factors, e.g. splenic microanatomy and the behavior of splenic immunocompetent and accessory cells which are responsible for the highly organized splenic microenvironments.


[Cytogenetics of malignant lymphomas].

[Cytogenetics of malignant lymphomas]. Cytogenetic findings contribute not only to a detailed classification of malignant lymphomas, but also to better prediction of prognosis. Therefore cytogenetic findings gain increasing importance in lymphoma diagnosis. Here, the characteristic chromosome abnormalities t(8;14)(q24;q32), t(2;8)(p12;q24), t(8;22)(q24;q11), t(14;18)(q32;q21), t(11;14)(q13;q32), + 12, + 3 and t(2;5)(p23;q35) and their molecular consequences are described.


[Molecular genetics of malignant non-Hodgkin's lymphoma]. Molecular genetical analyses are a valuable adjunct in the diagnosis and biological characterization of malignant lymphomas. They help to define clonality, lymphocyte lineage, and stage of differentiation of the lymphocyte clone. Investigations on the immune receptor gene rearrangement status can now be carried out by the fast and robust polymerase chain reaction (PCR) technique. However, this approach has its drawbacks and cannot completely substitute for Southern Blot experiments. Oncogene rearrangements are used not only to define clonality, but also give an idea about the origin of a lymphocyte clone in malignant lymphoma from a morphologically defined lymph node compartment. One has to be aware of the fact that gene rearrangement studies can only provide reliable results on the basis of a sound morphological evaluation of the lymphoid tumour tissue and that clonality of a lymphoproliferative disease does not necessarily imply a malignant course of disease for the patient.


[Cytokines and malignant lymphomas].

[Cytokines and malignant lymphomas]. Cytokines are potent modulators of the physiological immune response. A number of reactive processes are associated with a deregulation of this cytokine expression. Animal models with transgenic mice or transfection experiments have shown that an autocrine or paracrine pathway might be involved in tumor progression and/or tumorigenesis. The study of cytokine expression in malignant lymphomas showed a heterogeneous expression pattern with a number of cases which quantitatively show indications for a marked deregulation of the cytokine expression. The expression od IL-7 and IL-9 seem to be special features of Hodgkin's disease and large cell anaplastic lymphomas. Transfection experiment with IL-9 into mouse T cells results in an autocrine loop and tumorigenesis of the transfected cells. These tumors share a number of similarities to Hodgkin's disease and large cell anaplastic lymphomas in human.


[Epstein-Barr virus associated lymphocyte proliferation]. In recent years, techniques, probes, and reagents became available to reliably visualize individual Epstein-Barr virus (EBV)-infected cells, to assess EBV gene expression, and to analyze the clonal composition of EBV genomes in human tissues. Application of these techniques to more than 1000 lymphoid tissue specimens revealed (1) characteristic cellular and compartmental distribution patterns of EBV-infected cells in normal lymph nodes, reflecting the interference of EBV with physiologic B cell differentiation pathways, (2) an association of EBV with various mono- and oligoclonal lymphoproliferations ranging from benign conditions to overtly malignant lymphomas, and (3) characteristic patterns of EBV gene expression among EBV-associated lymphoproliferations. In the context of the established immortalizing and transforming properties of EBV, the findings support the concept of an etiologic role of EBV for cases of certain lymphomas such as Burkitt's lymphoma, anaplastic large cell lymphoma, Hodgkin's disease, and lymphomas arising in immunocompromised individuals. In contrast, lymphomas harboring EBV in only proportions of the tumor cells (such as cases of peripheral T cell lymphoma and some B cell lymphoma types) argue against an etiologic role in the primary process of malignant transformation for the virus in these instances. Since in many of these cases a proportion of the EBV infected tumor cells express the EBV oncoprotein LMP (latent membrane protein) the virus may influence, however, the proliferative properties as well as the morphological and molecular phenotype of the neoplastic cells.


[Autoimmune diseases and malignant lymphoma]. During the recent decade evidence accumulated, that autoantibodies exist with a high frequency in the normal B-cell repertoire. The autoreactive B-cell repertoire may undergo malignant transformation through the continuous challenge by autoantigen. Previous work on human paraproteins of plasmocytoma and immunocytoma has shown that a high proportion of paraproteins bind to self determinants. B-cell lymphoma may mimic the lesions in organotropic autoimmune disease, eg. Sjögren's disease, Hashimoto's thyroiditis and coeliac disease by the neoplastic expansion of autoimmune receptors. Considerable evidence has been obtained, that the specific receptor interactions of the lymphoma with the autoantigen may be of functional significance. More precise knowledge on receptor specificities would permit new approaches to the understanding and manipulation of autoimmune disease and lymphoma.


Impairment of peripheral nervous system in patients with non-Hodgkin's lymphomas treated with CBVPM/AVBP and CHOP schedules. Clinical examination and conduction velocity measurements in peripheral nerves have been done on 56 patients with non-Hodgkin's lymphomas of high malignancy (NHL). It is suggested that: the evaluation of the influence of chemotherapy on peripheral nervous system (PNS) is possible by means of systematic neurological and electroneurographic studies; electroneurographic assessment is most important in the diagnosis of early subclinical stages of peripheral neuropathy; toxic influence of CBVPM/AVBP protocol on PNS is greater than CHOP schedule; impairment of PNS due to chemotherapy is reversible in patients during complete remission (CR).


Unusual case of granular lymphocytes (GL) proliferation: simultaneous reactive and neoplastic proliferation. We report a case of a 55-year-old male with lymphoproliferative disease of granular lymphocytes. In the first year of follow-up reactive expansion of granular lymphocytes was observed during infectious episodes additionally to malignant proliferation. Histopathological studies revealed malignant lymphocytic infiltrations of the liver and gallbladder walls. The number of GL varied from 1.1 G/l to 17.8 G/l. Immunophenotyping studies showed surface phenotype CD3+, CD8+. There was markedly reduced NK cell function. The patient exhibited lack of severe parenchymal involvement, moderately increased white cell count (up to 21.0 G/l), severe neutropenia (0.06 G/l - 0.8 G/l) and recurrent infectious episodes.


[Clinical course of hormone refractory cancer of the prostate]. Analysis of the clinical progression of 61 patients with prostate cancer undergoing hormone therapy. PSA allowed early detection in 86.9% cases. In 25 patients no rescue treatment was instituted, and 36 patients were treated with estramustine phosphate resulting in decreased PSA levels in 58% and objective response in 36%. Of these, 82% showed decreased PSA levels for over six months. Survival rate was higher in respondent, treated patients and comparable in non-respondents, treated versus non treated patients.


Familial occurrence of renal and Müllerian duct hypoplasia, craniofacial anomalies, severe growth and developmental delay. Absence of the kidneys and of the Müllerian structures has been reported in many patients. We report on a brother and sister, born to nonconsanguineous parents, with renal hypoplasia, Müllerian duct hypoplasia, and strikingly similar facial abnormalities. Both sibs have severe growth and developmental retardation. We think that the unique clinical findings in these sibs represent a new syndrome. The embryological and genetic implications of this condition are discussed.


Abnormal regulation of insulin-like growth factor gene expression in peripheral blood mononuclear cells from patients with IgA nephropathy. We investigated insulin-like growth factor (IGF)-I and -II mRNA expression in peripheral blood mononuclear cells (PBMC) and T cells obtained from 31 patients with IgA nephropathy (IgAN), 43 patients with other types of glomerulonephritis and 16 health age-matched controls. The majority of patients with IgAN showed elevated IGF-I and -II mRNA expression in PBMC, while no IGF-I and -II mRNA expression was detected in PBMC obtained from patients with other types of glomerulonephritis or normal controls. In T cells obtained from IgAN, other types of glomerulonephritis and normal controls, however, IGF-I and -II mRNA expression was not detected. A positive correlation was noted between IGF-I and -II mRNA levels and urinary protein excretion. IGF-I and -II mRNA expression also correlated with the histopathological findings in the renal tissue of patients with IgAN. Sixty-nine percent of patients with more than 1.0 g/day proteinuria showed strong [more than (++)] IGF-I and -II mRNA expression in their PBMC. Eighty-one and 76% of patients with grade III and IV histopathological findings, respectively, showed strong IGF-I and -II gene expression in their PBMC. We also studied the clinical course of 11 patients with IgAN during hospitalization. The IGF-I and -II mRNA levels in these patients decreased gradually, as did proteinuria, after treatment. These studies suggest that abnormal regulation of IGF-I and -II gene expression in PBMC may be associated with the progression of IgAN and may be useful as an indicator of disease activity.