[Applied anatomy of the breast: blood supply and innervation]. Convinced of the importance of a precise understanding of anatomy in modern surgery, the author studied the arterial blood supply and venous and lymphatic drainage and re-evaluated the innervation of the mammary gland; 60 fresh cadavers, 350 thermographies and 5 in vivo arteriographies were analysed. Twenty years of surgical practice either supported or contradicted these anatomical findings. Schematically, the arterial blood supply is ensured by three plexuses: cutaneoglandular plexus, retroglandular plexus, intraglandular anastomotic plexus; the cutaneoglandular plexus corresponds to a combination of the dermal and the glandular blood supplies. The ectodermal embryological origin of the mammary gland clearly accounts for this common blood supply. This concept allowed the development of deepithelialised periareolar pedicle reduction mammaplasty and acts as a guide for subcutaneous mastectomies. The retroglandular plexus is supplied, in particular, by the musculocutaneous and, in this case, musculoglandulocutaneous arteries. This plexus ensures the blood supply of the remaining gland following posterior or inferior pedicle reduction mammaplasty techniques. The venous drainage was studied in particular detail. Two venous plexuses are present: one runs parallel to the arterial blood supply and the other is superficial, subcutaneous and anastomotic not only with the deep plexus, but also with the all of the surrounding regions. This plexus, quiescent under normal conditions, becomes functionally important in certain pathological conditions or after correction of mammary hypertrophy. The external and internal pathways of lymphatic drainage have been described for a long time. The authors describe the lesser known accessory pathways which nevertheless play an essential role in certain forms of metastatic spread or recurrence of breast cancer. Lastly, the authors describe the sensory innervation of the mammary gland which is an essential element for preservation of nipple sensitivity, in particular, following reduction or augmentation mammaplasty or even breast reconstructions.


[Prognostic factors in breast cancer].

[Prognostic factors in breast cancer]. Among the various factors reported as having significant prognostic value in primary breast cancers, the author discusses the value of well established "classical" prognostic factors used routinely and "new" prognostic factors developed over recent years as a result of progress in cell and molecular biology. The presence of axillary lymph node metastases remains the most important prognostic factor of recurrence, justifying post-surgical adjuvant therapy. However, in patients with negative axillary nodes (N-), the size of the tumour, Scarff-Bloom-Richardson (SBR and MSBR) histological grade, certain particular histological types (carcinoma in situ and tubular, colloid or pure papillary cancer) and hormone receptors (ER and PR) appear to be well established prognostic factors allowing the identification, within this group of N- patients who generally have a good prognosis, those patients with a low risk of recurrence and therefore not requiring adjuvant therapy. In contrast, the proliferative activity (ploidy and S phase, Thymidine Labeling Index, antibody Ki67), cathepsin D, thymidine kinase, EGF receptors, several genes including oncogene HER-2/neu, are recently developed prognostic factors whose significance needs to be confirmed by further studies.


[Histological typing of the breast by multifocal biopsies]. The current concept of high risk mastopathy was revolutionised by the work of Dupont and Page (1985), who demonstrated the importance of proliferative mastopathies in the assessment of the risk, particularly when they are associated with epidemiological factors. Based on these data, the Montpellier breast pathology study and research group (GERPAMM) developed on original method designed to define the precise histological profile of women considered to be at risk of breast cancer, despite the absence of any focal mammographic signs. This typing, consisting of a rigorous surgical protocol strictly complying with Page's histological definitions, was performed in women presenting a certain risk defined by clinical, cytological and radiological criteria (density and disseminated microcalcifications). This paper presents a preliminary review of 6 years' experience in 162 cases. The preliminary results confirm than many cases of atypical hyperplasia are not associated with a focal mammographic abnormality. However, in the absence of focal signs, certain types of disseminated microcalcifications with a morphological appearance suggestive of an intraductal origin, are significantly associated with high-risk histological signs. Histological typing is therefore useful to predict the cancer risk, to dedramatise cases without significant hyperplasia and to propose an adapted and justified approach to cases with a high histological risk.


[Screening of cancer of the breast].

[Screening of cancer of the breast]. Breast cancer is the commonest cancer in women. Screening for a severe and frequent disease with a long doubling time can be applied to breast cancer. Mammography is accepted by the population as a screening test, as it is simple, painless and safe. Many foreign studies combining either clinical examination and mammography or using mammography alone have confirmed the following elements: cancers are detected at an earlier stage than in the control population, screening of women under the age of 50 years does not provide convincing results, as a decreased mortality is only observed for women over the age of 50 years. Screening was introduced in France in 1989 by law and is now performed in 8 departments. The number of deaths prevented as a result of this action is estimated to be a minimum of 1,000 per year. Screening has positive effects on the quality of radiological equipment, improvement of preoperative detection techniques and on the accuracy of the pathology report. Inversely, its disadvantages include false-negative and false-positive results, leading to a certain number of negative operations. Screening will decrease the incidence of invasive cancers and mastectomies and the role of reconstructive surgery after mastectomy for breast cancer. However, the indications for plastic surgery in clinically detectable breast cancer will increase based on collaboration between breast cancer specialists and plastic surgeons.


[Primary surgery in the treatment of invasive cancers of the breast]. The modalities and indications for surgery in the treatment of breast cancers have changed considerably over the last 30 years with a succession of exclusive surgery, exclusive radiotherapy, then limited surgery with adjuvant radiotherapy, adjuvant chemotherapy and finally neoadjuvant chemotherapy. With the contribution of all of these treatment modalities, the authors discuss the respective roles of radical surgery and conservative surgery as first-line surgery for invasive breast cancers. After recalling its objectives, first-line surgery is then described in terms of its diagnostic role in the presence of a suspicious node, an patch of mastopathy, nipple discharge or subclinical lesions. The various radical and conservative techniques of primary curative surgery are then described in the context of combined therapy (adjuvant radiotherapy and/or chemotherapy): no longer Halsted's radical mastectomy, by modified Patey's mastectomy with limited lymph node dissection and especially partial mastectomies (quadrantectomy, lumpectomy) with axillary lymph node dissection, alone or combined with radiotherapy. The implications on the cosmetic result and the various modalities of reconstructive surgery are also discussed.


[Exclusive radiotherapy and brachytherapy in the treatment of breast cancer]. Exclusive radiotherapy is one of the modalities of conservative treatment for breast cancer. It is designed to destroy the tumour without surgery and to retain a treated breast comparable to the contralateral breast. The efficacy of radiotherapy, alone or in combination with brachytherapy, expressed in terms of overall survival and disease-free survival, has been documented by a large number of retrospective studies. The results published, especially by French teams, pioneers in this field, are comparable to the results reported for other conservative and radical techniques. The quality of the cosmetic results is inversely proportional to the dose delivered and decreases with the observation time. Although the cosmetic role of radiotherapy is modest, its therapeutic role remains essential in the case of initially or subsequently inoperable lesions. The current development of primary chemotherapy and rehabilitation techniques have limited the indications for exclusive radiotherapy plus or minus brachytherapy, but have paradoxically led to a renewed interest in this technique.


[Primary chemotherapy in the treatment of breast cancer]. Between 1980 and 1992, 457 consecutive patients with initial breast cancer entered two successive protocols combining neoadjuvant chemotherapy, hormonotherapy (tamoxifen) and locoregional radiotherapy (teleradiotherapy and boost by iridium) as exclusive locoregional treatment. Cytological diagnosis, hormone receptors, cytological grading were provided by fine needle aspiration. Both protocols included velbe, thiotepa, methotrexate, 5FU and adriamycin with some minor differences regarding the schedule of doses and their number during induction and during the consolidation phase. In both studies, over 50% patients had locally advanced breast cancer (IIb, IIIa or IIIb). Chemotherapy induced tumor regression over 50% in 91% patients of the first protocol (30% complete clinical remission CR) and in 94% patients of the 2nd protocol (40% CR): in this protocol 20 poor responders were given a rescue protocol (2 CR; 9 partial remissions). The 5 year actuarial rate of breast preservation is 94% and the 5 year actuarial rate of local relapses is 15%. The cosmetic results according to Danoff are excellent 20%, good 55%, mean 35%. Disease free survival and overall survival compare favorably to published data: they depend on TNM stages, tumor differentiation and chemotherapy induced early tumor regression.


[Plastic surgery and breast cancer. Are there contraindications for plastic surgery?]. Plastic surgery has acquired an important place in primary breast cancer treatment (conservative or radical) and in the treatment of sequelae. The authors have tried to define, based on their experience, the contraindications for breast reconstruction. They are rare from a technical point of view. The carcinologic contraindications are relative: highly aggressive cancers, locally advanced cancers, cancers with metastases or recurrences. Radionecrosis and radio-induced sarcomas, treatment sequelae are also contraindications for breast reconstruction. General contraindications are relative (major obesity, smoking, diabetes, general weakness). Psychological contraindications must be taken into consideration. The authors conclude that contraindications for breast reconstruction are mainly carcinologic and the decision for reconstruction is usually taken by the patient after complete medical information.


[Plastic surgery and conservative treatment of breast cancer. Indications and results]. After conservative treatment for breast cancer, 75% of patients have good cosmetic results, but 20 to 25% of patients have a fair or a bad result. The tumor itself is responsible for some of these bad results (tumor volume, location in the inferior quadrants of the breast) but more often, failures are related to surgery and/or radiotherapy. Some patients will then ask for reconstructive surgery. It should always be preceded by a careful examination of the breast, both with an oncologic and a reconstructive approach. The techniques used are numerous, ranging from simple reexcision of the lumpectomy scar to mastectomy with immediate TRAM flap reconstruction. We believe that plastic surgery techniques should be used as soon as the initial lumpectomy, as they help to fill in the defect. In the case of a tumor located in the inferior quadrants, bad cosmetic results are twice as frequent as in the upper quadrants: we treated 16 of these patients with immediate bilateral breast reduction, reshaping the breast at the same time as the lumpectomy, and achieving symmetry of the contralateral breast. This technique did not interfere with radiotherapy or chemotherapy. When radiotherapy followed surgery, cosmetic results were good. Local and distant recurrences were not modified by the adjunction of a breast reduction to the lumpectomy. In 49 cases, we also proposed a bilateral breast reduction for larger tumors (T > 3 cm, bifocal cancer). 4-year local recurrence rate was less than 10%: this technique could help to extend the indications for conservative treatment for breast cancer. More cases and longer follow-up are necessary.


[Conservative and esthetic surgery in cancer of the breast]. After a review of the studies justifying conservative surgery in the treatment of breast cancer, the author describes the possibilities of improving the results of this surgery either by the use of flaps or prostheses or (in the case of large breasts) by performing mammoplasties. The review of a series of 116 cases illustrates the range of possibilities of cosmetic surgery.


[Immediate mammary reconstruction in the radical treatment of cancer of the breast]. Based on a series of 516 patients operated between 1976 and 1991, the authors present their experience of the various aspects of immediate breast reconstruction (IBR). A prosthesis was used in the majority of cases (80%) and the essential technical aspect was the creation of a complete muscular compartment, possibly by combining pectoralis major and serratus anterior, latissimus dorsi (5%) and by using an expander (8%) or even a musculocutaneous flap. The rectus abdominis musculocutaneous flap (TRAM, 10%) had the advantage of allowing IBR without a prosthesis. The mastectomy scar plays a major role in determining the final shape of the breast: the skin resection must be modulated according to the site of the tumour. The complications observed (40%), which required removal of the prosthesis in 12% of cases, were either immediate complications (20%), some of which (infections, necrosis, dehiscence) tended to delay adjuvant therapy, or secondary complications, principally grade III-IV contracture (20%). Evaluation of the cosmetic results of IBR in comparison with a population undergoing secondary reconstruction over the same period, did not reveal any significant difference between the two approaches. The authors discuss in detail the oncological and technical arguments for and against IBR and conclude on the psychological advantages of IBR for mastectomised patients.


[Secondary mammary reconstruction after radical treatment of cancer of the breast. Indications and results]. The author reports his experience of more than 500 secondary total breast reconstructions over a period of 8 years. Every patient should at least be referred for an opinion concerning the type of reconstruction which can be proposed and the delays are defined. The role of breast reconstruction and follow-up in oncological surveillance is explained. The complications most frequently encountered after mastectomy and lymph node dissection and after radiotherapy are described together with their consequences for reconstruction. This reconstruction is always proposed in two operative sessions consisting of recreation of a breast volume and restoration of symmetry, while the areola is only reconstituted on stable volumes, possibly as an outpatient procedure. A prosthesis is used to create volume in 75% of cases, even after irradiation, without a previous expansion phase by means of a thoraco-abdominal ascension flap. A myocutaneous flap is required in 25% of cases; the TRAM was used in 15% of cases, particularly in obese patients, in the absence of any abdominal contraindication; and a latissimus dorsi flap was used in 10% of cases. The advantages, indications, limitations, contraindications, complications and disadvantages of each technique are described. The history and the risk of cancer in the contralateral breast and the attitude adopted in such a case are discussed. Morphologically, a symmetrisation prosthesis was necessary in 5% of cases, but never in the case of TRAM; in hypertrophic and/or ptosed breasts, a symmetrisation plasty was necessary in 50% of cases of prosthesis, 40% of cases of latissimus dorsi flap and 30% of cases of TRAM and, in this latter case, always at a second operation. Reconstruction of the areolo-nipple complex was performed in only 70% of cases. The nipple is best reconstructed by longitudinal splitting of the opposite nipple or more rarely by a local, tattooed flap. In the case of a local flap, the nipple is always grafted from a thigh flap, despite its disadvantages; more than 90% of nipples can be tattooed.


[Secondary microsurgical reconstruction of the breast and free inferior gluteal flap]. A technique of secondary breast reconstruction by microsurgical transfer of an inferior gluteal flap is presented. The principal characteristics of the inferior gluteal myocutaneous flap, described for the first time by the author in 1978, are presented: anatomical bases, harvesting technique. Breast reconstruction with this flap is performed in three operative steps. Step 1: application of a skin expander in the breast region in order to re-create the mammary space. Step 2: microsurgical transfer of the de-epithelialized flap, rolled up to create a pseudo-mammary gland, then insertion into the expanded mammary space. Step 3: reconstruction of the areola-nipple complex from the contralateral side and restoration of breast symmetry. The results of breast reconstruction according to this technique were evaluated in a series of 14 cases operated between 1987 and 1991, while the sequelae of the gluteal donor site were evaluated on a series of 65 free inferior gluteal flaps performed between 1977 and 1991. The advantages of this procedure are the natural curvature and softness of the reconstructed breast, the moderate sequelae at the donor site, leaving a scar dissimulated in the gluteal fold. This technique was compared with other reconstruction techniques: microsurgical procedures (non de-epithelialized inferior gluteal flap, superior gluteal flap, lateral mammary flap, etc.) and conventional procedures (breast expansion+prosthesis, latissimus dorsi flap, rectus abdominis flap). In conclusion, another technique is described, which appears to offer the advantages of the de-epithelialized inferior gluteal flap without the disadvantage of microsurgical transfer: reconstruction with a de-epithelialized rectus abdominis pedicle flap after expansion of the mammary space.


Tumorigenicity and metastatic ability of MmB16 mouse melanoma cell line and its two Aleuria aurantia agglutinin resistant variants. The availability of neoplastic cell lines with well defined growth characteristics has greatly facilitated study of the tumor phenotype, tumor progression and metastatic process. MmB16 cell line has been established in vitro from the B16 mouse melanoma serially passaged in C57BL/6 mice. From MmB16 cells two lectin-resistant (LecR) variants were selected with the use of Aleuria aurantia agglutinin (AAA). The correlation between the lectin resistance and their in vivo growth parameters, especially tumorigenicity and metastatic ability, were evaluated. The local tumor growth and the average survival time of mice after subcutaneous (s.c.) inoculation of AAAR variant cells did not differ significantly from those of the parent MmB16 cells. However, the AAAR variants revealed significantly higher experimental lung colonizing ability after intravenous (i.v.) administration and slightly increased spontaneous metastatic ability after s.c. inoculation, as compared to parent MmB16 cells.


The migration of granulocytes from allergic and nonallergic infiltrations in patients with atopic asthma. The granulocyte migration inhibition tests both in vivo and in vitro from allergic skin infiltrations were carried out in 30 patients with atopic asthma and in 20 healthy people used as a control. It was found that the migration of leukocytes from allergic skin infiltrations was defective with the lowest ability to migrate. Neutrophils comprised about 80% cells found in the cutaneous allergic infiltrations.


Effect of Pre-S1 protein on the long-term cultures of human lymphocytes after hepatitis B immunization. Long-term cultured T-cells, reactive to Pre-S1 protein, were developed from peripheral blood mononuclear cells (PBMC) of individuals after recovery from hepatitis B infection and of vaccine recipients by in vitro Pre-S1 protein stimulation in the presence of IL-2. The proliferative responses to Pre-S1 protein and functional activities of cultured T-cells were characterized.


Studies on effect of pesticide Chlorfenwinfos on mouse immune system. The effect of organophosphate pesticide--Chlorfenwinfos on the selected parameters of humoral and cellular immunologic response in mice was investigated. Hematologic and histologic examinations were run parallelly. The animals were treated with pesticide p.o. during 90 days in doses 1/100, 1/50 and 1/25 of LD50. It was found that Chlorfenwinfos exerts immunotropic effect. After high doses the strong suppressive effect in PFC and EA rosettes was observed. Significant involution of thymus was noted. Il-1 activity, DTH reaction (24 h after challenge) and endogenous and exogenous spleen colonies were stimulated. It seems that immunotropic effect of this pesticide is reversible. Three weeks after the exposure to this compound had been stopped, PFC, IgG and IgM level came back to the normal value.


Padma 28 modifies immunological functions in experimental atherosclerosis in rabbits. The effect of Padma 28 on selected parameters of humoral and cellular immune reactions in rabbits subjected to experimental atherosclerosis was studied. The drug significantly reduced the size of atherosclerotic plaques in the aorta and restored to a varying extent the immune functions studied. The possible mechanism by which Padma 28 may exert its anti-atherosclerotic action is discussed in the scope of the immunological theory of atherosclerosis.


Humoral response in mice immunized with outer membrane proteins of Hafnia alvei. Protective activity of anti-OMP-antibodies. Intraperitoneal immunization of mice with outer membrane proteins (OMP) of Hafnia alvei induced in the animals a synthesis of specific antibodies. The antibody levels, determined by ELISA test, were found to be relatively low in the sera of mice immunized with a single dose (5 micrograms) of OMP and after a second immunization. However, they were higher in mice immunized with three doses of OMP. The antibodies were present in circulation for a relatively short time after immunization. Serum containing anti-OMP antibodies given intraperitoneally to normal mice protected them only against challenge with a homologous Hafnia strain.


Binding properties and expression of the Fc gamma receptors on guinea pig peritoneal macrophages treated with inhibitors of glycosylation. The effect of inhibition of glycosylation in guinea pig peritoneal macrophages on interaction of their surface Fc gamma receptors with guinea pig and rabbit IgG was studied. The inhibitors used were tunicamycin and monensin. The cells treated with tunicamycin incorporated markedly less [3H]mannose, bound less peanut (PNA) and wheat germ (WGA) lectins and showed diminished ability of binding IgG in comparison with control cells. Treatment of the cells with monensin resulted in an increased incorporation of [3H]mannose, increased binding of PNA but a decreased binding of WGA. Monensin affected binding of guinea pig IgG2 and rabbit IgG to macrophages and had no effect on guinea pig IgG1 binding. Analysis of binding parameters showed that although the number of IgG-binding sites on treated cells was significantly lower, especially in the case of tunicamycin, the apparent association constants were 2-4 times higher than in control cells. The effect of tunicamycin and monensin on parameters of binding of guinea pig IgG2 or rabbit immunoglobulins was much more pronounced than in the case of binding guinea pig IgG1. The results showed that glycosylation modulates expression and IgG binding ability of the Fc gamma receptors on the surface of guinea pig peritoneal macrophages.


Hemagglutinins of Beauveria bassiana strains: the effect of growth conditions on their production. Forty strains of Beauveria bassiana were screened for their ability to produce hemagglutinins. It has been found that majority of mycelial extracts but not cultural broth display non specific hemagglutinating activity toward animal and human type AB and A, B, O erythrocytes when microorganisms are cultivated on rich in amino acids media supplemented with saccharose. The formation of hemagglutinins in mycelia is strongly dependent on composition of medium and associated with a production of extracellular lipases, chitinases and amylases. No monosaccharide binding specificity of obtained hemagglutinins toward glucose/mannose, N-acetylglucosamine, N-acetylgalactosamine/galactose, L-fucose and sialic acid was observed.


Purification and some properties of hemagglutinin from Beauveria bassiana. A novel hemagglutinin produced by insect pathogen Beauveria bassiana was isolated from mycelium of the stationary growing microorganism and purified by adsorption on carboxymethyl cellulose followed by separation on Spherogel TSK--phenyl 5 PW column using high performance liquid chromatography. The purified hemagglutinin was homogeneous in polyacrylamide gel electrophoresis and isoelectric focusing. Its molecular weight was estimated to be around 25,000, isoelectric point was found at pH 8.6 +/- 0.2. Amino acid composition of purified B. bassiana hemagglutinin was determined by HPLC fluorometric analysis of o-phthaldialdehyde derivatives of protein hydrolysate. Purified hemagglutinin agglutinated some animal and all human erythrocytes independently of blood group ABO phenotype. The observed hemagglutination is not inhibited by glucose/mannose, N-acetylglucosamine, N-acetyl galactosamine, galactose, L-fucose and sialic acid.


The use of antibodies labelled with dyes for fast and simple assay of some human proteins by immunofiltration technique. Immunofiltration technique with polyclonal and monoclonal antibodies for semi-quantitative assays of human albumin, chorionic gonadotropin, immunoglobulin G and transferrin was elaborated. An amount of antibody was immobolized in the form of 6 radially located small bars on a dry test filter made of glass microfibre sheet. The other amount of antibody, used in solution, was labelled with some dyes like commercial disperse dyes, colloidal elements, formazans and polypyrrole. Number of colour bars appearing on the test filter showed ranged of analyte concentration. Good results were obtained using antibodies labelled with colloidal gold, Disperse Red 11 and formazan from MTT. Assays with monoclonal antibodies were more sensitive than with polyclonal antibodies.


Effect of recombinant human granulocyte-macrophage colony-stimulating factor on chemotherapy-induced myelosuppression. We have studied the efficacy of recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) in stimulating haematopoiesis of patients with chemotherapy-induced myelosuppression. Ten patients with various myeloid and lymphoid neoplasias were treated daily with a single subcutaneous dose of rhGM-CSF (5 micrograms/kg/day), for a period of 5-10 days, after receiving highly myelotoxic chemotherapy. The treatment increased the white blood cell count (WBC) in nine of ten patients, primarily because of an increase in the number of neutrophils. Increase in bone marrow myeloid precursor cells, and myeloid to erythroid cell rations accompanied the white-cell response. In spite of this, five patients demonstrated rapid platelet recoveries, and in two patients erythrocyte levels increased after GM-CSF treatment. No toxicity was encountered with the cytokine therapy. Although rhGM-CSF was shown to stimulate haematopoiesis in patients with chemotherapy-induced myelosuppression, additional studies are needed to assess whether the use of GM-CSF will reduce chemotherapy-associated morbidity and improve response rates and survival among patients with neoplasias.


The influence of recombinant human tumor necrosis factor (rh-TNF alpha) on granulocyte-macrophage progenitor cells (CFU-GM) and clonogenic leukaemic blasts (CFU-L) in cultures in vitro. We investigated the influence of recombinant human tumor necrosis factor alfa (rh-TNF alpha) on the clonal growth of CFU-GM from 14 normal individuals and clonogenic blasts (CFU-L) from 16 patients with acute myeloid leukaemia (AML) in semi-solid cultures in vitro. Recombinant human TNF was produced by the Center of Molecular and Macromolecular Studies of the Polish Academy of Sciences (Lódź, Poland) as a lyophylized powder. This factor was added to the culture medium at the concentrations of 10, 100, 1000 U/ml. A dose-dependent growth inhibition of CFU-GM and AML CFU-L was observed. The inhibitory effect of rh-TNF alpha was significantly greater on CFU-L than CFU-GM.


[Polymorphic ventricular tachycardia. Analysis of the onset of the episodes]. To analyze the spontaneous onset of events for polymorphous ventricular tachycardia, to determine the importance of this parameter in the clinical and electrophysiologic context. We evaluated 124 modes of onset of polymorphous ventricular tachycardias recorded by 24 hr of continuous ECG monitoring in 6 patients. Four patients were using quinidine and diuretics, and two patients only diuretics. We determined the two preceding cycle in milliseconds from the initiating events and also the induced cycle (cycles A, B and C). Careful analyses of T and U waves alternans and QT ou QTU intervals inside and outside the episodes of tachycardia. In 105 episodes (84%) the events were pause-dependent; in 12 episodes (10%) they occurred without pauses but after a ventricular fusion and in 7 episodes (6%) also without pauses but with sudden cycle (C) shortening (R on T phenomena). The pause-dependent episodes were only seen in patients using quinidine with the association of diuretics and non-pause related episodes were registered in patients using diuretics. All patients had prolonged QTU intervals outside the episodes. There were a linear correlation (r = 0.865) between the amplitude of the U waves of the cycles C and duration of cycles A and B, in pause-dependent episodes. The contribution of this study is that: the analyses of the spontaneous onset of polymorphous ventricular tachycardia can allow the differentiation of typic forms of torsades des de pointes (pause-dependent) and other atipic forms. The former type occurred probably as a result of EADs provoking triggered rhythms. The latter could be better explained as polymorphous ventricular tachycardia due to reentry mechanisms or enhanced automatic focus. Only the tipic forms should be acutely benefited with regularization of cardiac cycles with cardiac pacing.


[The use of primary coronary angioplasty in acute myocardial infarction in patients over 70 years of age]. To evaluate the use of primary coronary angioplasty (PTCA) in patients older than 70 years, evolving with acute myocardial infarction, without the previous administration of thrombolytic agents. Forty-two patients with acute myocardial infarction (AMI) and more than 70 years of age (m = 76.4y). There were 54.7% men and 43% of them had anterior MI. PTCA was carried out during the first 12 hours of evolution and in the first 3 hours of duration in 47% of them. PTCA was done only to the AMI related artery, which was the left descending artery in 43%, the right coronary artery in 47% and the left circumflex in the remaining patients. Nineteen percent of these patients were in Killip class III e IV. Primary success was achieved in 86%. The in hospital mortality was 14.2%, and it was superior in female gender (26.3%), in Killip class III and IV (37.5%), in those with multivessel coronary disease (16.6%) and in those where primary PTCA failed (33%). There were 9.3% of reinfarction, but no major hemorrhages happened. Late angiography was done in 50% of patients, showing 72% of patency in the AMI related artery, and a significant improval of global ejection fraction and of the wall motion, particularly, in those who maintained arterial patency. Primary PTCA, without former use of thrombolytic agents, when applied early in elderly patients evolving with AMI, has a high success rate and low mortality rate in this subset of high risk patients. It also shows no major hemorrhagic complications.


[Malnutrition in dilated cardiomyopathy. Correlation with echocardiographic indices of left ventricular function]. To evaluate the incidence of severe protein-calorie malnutrition in patients with dilated cardiomyopathy (DC), and its correlation with left ventricular contractility. Group A--51 patients with DC in decompensated congestive heart failure class III or IV, 36 men, aged 51.9 +/- 15.6 years. Group B--25 patients admitted for elective myocardial revascularization with normal LV contractility, 20 men, aged 57.2 +/- 10.5 years. Tricipital skinfold thickness (TS) and mid-arm muscle circumference (MAMC) were obtained in all patients. Severe protein-calorie malnutrition was defined when both measurements were below the fifth populational percentile (Frisancho tables). In Group Am the echocardiographic left ventricular (LV) diastolic diameter (DD), ejection fraction (EF) and systolic volume (SV) were obtained. Those LV parameters were compared between DC patients with and without severe malnutrition. Correlation analysis were performed between TS, MAMC and LV DD, EF, and SV, in the patients of Group A. Severe malnutrition occurred in 7/51 (13.7%) of Group A, and none in Group B. TS values were of 8.90 +/- 4.47 cm in Gr. A and 23.48 +/- 8.52 in B (p < 0.001). MAMC measured 22.25 +/- 3.13 cm in Gr. A and 23.58 +/- 8.52 in B (p = 0.03), LVEF was of 36.29 +/- 9.43% in severe malnutrition patients and of 37.84 +/- 9.78 in the other patients of Group A (p = 0.70). Conversely, LVDD was of 70.90 +/- 11.3 mm vs. 70.75 +/- 8.54 mm (p = 0.98), and LVSV was of 113.0 +/- 52.7 ml vs. 137.6 +/- 56.8 (p = 0.45), when compared severe malnutrition with the rest of patients of Group A. No correlation was found between TS and MAMC and LV, EF, DD and SV in Group A. Severe malnutrition was frequent in patients with DC and heart failure. TS measurements, reflecting caloric reserves, were more affected. Echocardiographic parameters of LV function did not correlate with nutritional status.


[Technical modification of total cavo-pulmonary connection]. A variation of total cavopulmonary connection without anastomosing the superior vena cava to the right pulmonary artery branch is presented. Both vena cava flow go through an intra atrial tunnel to the right atrial appendage, which is anastomosed to the right pulmonary artery, in anatomical eligible cases.


[Current approach in the treatment of isolated coronary arterial stenosis associated to arteriovenous coronary fistula]. Congenital coronary arteriovenous fistulae are commonly associated with complications which include congestive heart failure, bacterial endocarditis, angina pectoris, secondary to "coronary steal" phenomenon and fistula rupture. Conventional treatment of large coronary arteriovenous fistulae is surgical ligation. In this report we describe the data and therapeutic approach of a patient with a severe coronary stenosis in a large diagonal branch in whom PTCA was successfully conducted, while, in this opportunity no embolization of the fistula was performed.


[Directional atherectomy and coronary angioplasty: a therapy complementary to myocardial revascularization surgery]. A white male patient, 59 years old, with two prior surgical myocardial revascularization and unstable angina, was submitted to coronary arteriography that showed: all the saphenous vein grafts patent and obstruction of 75% in the saphenous vein graft to the second marginal branch of left circumflex artery. Left internal mammary artery (LIMA) was angiographically normal and 80% stenosis was detected in the distal segment of the left anterior descending coronary artery (LAD). The patient was submitted to directional coronary atherectomy for saphenous vein graft and coronary angioplasty for distal-LAD. Both procedures were successfully performed.


[Cardiomyopathy induced by incessant ventricular tachycardia ("tachycardiomyopathy"): cure after control of arrhythmia]. A case of severe dilated cardiomyopathy in a young boy presenting with incessant ventricular tachycardia, who had been referred for heart transplantation is reported. Complete resolution of dilated cardiomyopathy followed arrhythmia control with oral amiodarone. Such evolution strongly suggests a cause-effect relationship between incessant ventricular tachycardia and dilated cardiomyopathy in this particular case.


[Treatment of hypertensive crisis in outpatients with sublingual isradipine]. Evaluate the efficacy and tolerability of isradipine, a new dihydropyridine calcium antagonist in the therapy of outpatients hypertensive crisis. Twenty seven patients with mean age of 37.2 +/- 2.5 years (ages ranging from 18 to 59 years old) of different races (14 white, 13 not white); 15 men and 12 women, with diastolic blood pressure over 130 mmHg and without signs of recent target organ damage were studied. The patients were divided in three groups according to the used dosage of Isradipine tablets by sublingual route. Group I (n = 10): 1.25 mg; Group II (n = 10): 2.5 mg and Group III (n = 7): 5.0 mg. Arterial blood pressure levels and heart rate were determined before the drug administration and every 30 minutes until 120 minutes after dosing. Mean arterial blood pressure (MABP) decrease significantly in all patients from 153.43 +/- 4.3 to 124.0 +/- 2.3 mmHg after 60 minutes and to 118.0 +/- 2.1 mmHg after 120 minutes (p < 0.001). Heart rate did not show significant changes with the drug. Clinical significant side effects were not observed. The comparative analysis of MABP curves did not show significant differences among the groups I, II and III. However, a tendency of a greater decrease in MABP was observed in the patients of group III. Isradipine tablets in the dosages of 1.25, 2.5 and 5.0 mg by sublingual route is effective and well tolerated in the treatment of ambulatorial patients with hypertensive crisis.


[Captopril in mild and moderate arterial hypertension resistant to diuretic therapy. A multicenter study]. To evaluate the antihypertensive effect of captopril in mild and moderate hypertensive patients uncontrolled with diuretics. Low dose of captopril (25 to 50 mg) bid were associated during 9 weeks in 120 patients previously treated with 100 mg of hydrochlorothiazide. A subgroup of patients (74) were followed additionally for 3 weeks with the same dose of the drugs administered as a single dose. The patients were clinically evaluated after two weeks placebo, and each three weeks of active drugs. Blood pressure normalization were considered when diastolic arterial pressure was < or = 90 mmHg. Laboratory tests were measured before diuretic, before captopril and at the end of combined twelve weeks treatment. After 15 days washout, the baseline supine arterial pressure, 168 +/- 2/ 109 +/- 1 mmHg decrease significantly with diuretic to 151 +/- 1/ 101 +/- 1 mmHg and the drop was further increased with captopril b.i.d., with a mean dose of 44 +/- 1 mg, to 137 +/- 1/ 90 +/- 1 mmHg. Blood pressure normalization was obtained in 58% patients with captopril b.i.d. and in 63% as single dose. Blood pressure normalization was achieved in 63% of non-white patients and in 56% patients over 45 years old. Plasmatic potassium decreased significantly with diuretic and did not recovered when captopril was associated. Our results indicate that the addition of low dose of captopril twice or once a day may result in a marked additional blood pressure reduction in cases of insufficient control by the diuretic alone.


Transforming growth factor beta stimulates mitogenically mouse NIH3T3 fibroblasts and those cells transformed by the EJ-H ras oncogene. TGF-beta 1 stimulates thymidine incorporation and the growth rate of mouse NIH3T3 fibroblasts and of those cells transformed by the EJ-H-ras oncogene (TR15 cells), in the presence and the absence of serum. Thymidine incorporation, in serum-deprived cells, is stimulated to a higher degree by 0.1-1 ng/ml of TGF-beta in NIH3T3 than in TR15 cells, which have a 10-fold higher basal level of incorporation. In both cell types TGF-beta 1 is as active, or more active than other mitogens (TGF-alpha, PDGF-AB, bFGF) at the same concentration. The growth rate of NIH3T3 cells, in low serum or serum-free (S-) medium, is stimulated by only 10 picograms/ml of TGF-beta 1, and that of TR15 cells, in S- medium, by only 1 picogram/ml. In contrast, TGF-beta 1 inhibits mitogenically unestablished mouse embryo fibroblasts and these fibroblasts immortalized spontaneously and able to grow in S- medium. It also inhibits the anchorage-independent growth of TR15 cells. NIH3T3 and TR15 cells respond, similarly, to TGF-beta activated by acification of their culture medium. The kinetics of thymidine incorporation and of activation of the c-myc proto-oncogene, observed already after 1 hr, in treated NIH3T3 and TR15 cells, suggests a direct mitogenic stimulation. The level of activated c-myc RNA is 2-fold higher at 2 hr, and subsequently decreases relatively less in the TR15 cells.


Basic fibroblast growth factor is synthesized and released by isolated ovine fetal growth plate chondrocytes: potential role as an autocrine mitogen. Basic fibroblast growth factor (basic FGF) is a mitogen for isolated epiphyseal growth plate chondrocytes. To determine whether basic FGF might function as an autocrine stimulus to longitudinal skeletal growth in utero, we investigated the synthesis and release of basic FGF by isolated growth plate chondrocytes from the ovine fetus, the expression of mRNA for a high affinity basic FGF receptor by these cells, and the contribution of endogenous basic FGF to the DNA synthetic rate of the cells in vitro. Chondrocytes were isolated from the proximal tibial growth plate of the lamb fetuses between 35 and 132 days' gestation using collagenase, and were cultured in monolayer before use between passages 3 and 6. Viability was confirmed over the duration of the experiments by the exclusion of trypan blue, and an absence of lactate dehydrogenase accumulation in conditioned medium. Immunocytochemistry of chondrocyte monolayers showed immunoreactive basic FGF to be present in the cytoplasm of approximately 80% of sub-confluent cells which was accompanied by pronounced nuclear staining in approximately 30% of cells. Serum-free, conditioned culture medium, extracellular matrix and chondrocyte cytoplasm contained 52 +/- 2 pM/micrograms DNA, 66 +/- 2 pM/micrograms DNA and 22 +/- 3 pM/micrograms DNA basic FGF, respectively (mean +/- S.E.M., n = 8 fetuses), for cells obtained from animals of 35-40 days' gestation when assessed by radioimmunoassay. Chondrocyte-conditioned medium increased endothelial cell proliferation in vitro (a specific bio-assay for basic FGF and related peptides); and the mitogenic activity was removed from conditioned medium by incubation with heparin-Sepharose demonstrating that this was due to heparin-binding protein(s). Western blot analysis of conditioned medium using a specific basic FGF antibody revealed a single immunoreactive protein of approximately 18 kDa molecular size. The appearance of radiommunoassayable basic FGF in conditioned medium, extracellular matrix, and chondrocyte cytoplasm observed during culture was blocked by co-incubation with cycloheximide. The levels of immunoreactive basic FGF present in each compartment decreased with gestational age as did basal DNA synthetic rate assessed by the incorporation of [3H] thymidine. Incubation of chondrocytes with transforming growth factor beta, resulted in a significant increase while exposure to insulin-like growth factors or insulin caused a decrease, in the content and release of basic FGF. Basic FGF presence was unaltered when medium was supplemented with varying amounts of glucose (2.7-16.7 mM). In situ hybridization on cell monolayers using a cRNA probe encoding the high affinity flg receptor for FGFs showed an abundant expression of mRNA for the receptor.(ABSTRACT TRUNCATED AT 400 WORDS)


Expression of interleukin 5 by the CD4+CD45R0+ subset of human T cells. The expression of IL5 by CD4+CD45RA+, CD4+CD45R0+ and CD3+CD8+ subsets of human peripheral blood mononuclear cells was assessed. Interleukin 5 expression was detected by RNA extraction, reverse transcription and polymerase chain reaction. Populations of highly purified cells were obtained by a protocol of sequential plastic adherence, magnetic bead separation and flow cytometric cell sorting. IL5 was clearly expressed in the CD4+CD45R0+ subset from 3 to 48 hr after activation. The CD4+CD45RA+ and CD3+CD8+ subsets expressed very much less IL5. By contrast, IL2 expression was readily detected in all sorted populations. Thus, in activated CD4+ cells, IL5 was predominantly expressed in the CD4+CD45R0+ subset, a pattern of expression corresponding to that reported for a number of other cytokines, and differing from that of IL2.


Characterization of the mouse PDGF A-chain gene. Evolutionary conservation of gene structure, nucleotide sequence and alternative splicing. The mouse platelet-derived growth factor (PDGF) A-chain gene has been structurally characterized and compared with its human counterpart. The organization of the two genes is similar. Both consist of 7 exons spaced by 6 introns of corresponding sizes. As in the human gene, exon 6 encodes a sequence which is alternatively spliced. When present, it codes for an alternative C-terminus of the A-chain. In intron 5, conserved stretches of nucleotides, potentially involved in the regulation of the alternative splicing, are identified. The untranslated sequences show a high degree of nucleotide sequence identity and several conserved consensus binding sites for transcription factors are identified within the 5' untranslated as well as in the 5' flanking region.


Effects of insulin-like growth factors (IGFs) and IGF receptor antibodies on the proliferation of human breast cancer cells. It has been shown previously that MCF-7 cells proliferate in response to nanomolar concentrations of IGF-I and IGF-II. It has also been reported that the actions of both peptides are mediated through the IGF-I receptor. To further characterize these observations, we used MCF-7 and Hs578T cell lines in the serum-free/phenol red-free system developed by Ogasawara and Sibarsku, 1988. Cell proliferation was studied in the presence of insulin, IGF-I and -II and a series of growth factor receptor antibodies. No effect was observed on Hs578T cell proliferation with any of the growth factors. However, MCF-7 cells were stimulated 4-5 fold with IGF-I and insulin, while IGF-II was only slightly less potent. alpha IR3, a monoclonal antibody directed against the IGF-I receptor, was stimulatory when added alone. However, alpha IR3 blocked approximately 50% of the IGF-I response, only 5% of the insulin response, and did not block the IGF-II effect on cell proliferation. These data suggest that alpha IR3 and IGF-I are acting as agonists through the IGF-I receptor, but that insulin and IGF-II are acting through other receptors. Two different IGF-II/M-6-P receptor antibodies and an insulin receptor antibody failed to significantly block IGF-II actions. All three antibodies were stimulatory when added alone. beta-gal inhibited 27% of the IGF-II response and had no effect when added alone. Since beta-gal decreases the binding affinity of the IGF-II/M-6-P receptor for IGF-II and does not bind to the IGF-I or insulin receptor, these data suggest the possibility that IGF-II mitogenic action is mediated through the IGF-II/M-6-P receptor. In summary, these data indicate that nanomolar concentration of insulin, IGF-I and IGF-II are potent mitogens in MCF-7 cells and can potentially stimulate cell proliferation through all three receptors.


Gamma-interferon-induced nerve growth factor receptors in colorectal carcinoma cell lines. Gamma-interferon (gamma IFN) was found to induce expression of the 150,000 M(r) cell surface and the 35,000 M(r) chromatin receptors for nerve growth factor (NGF) in the SW1116 colorectal carcinoma cell line that does not express NGF receptors. In the SW707 colorectal carcinoma cell line that expresses a low level of NGF receptors, gamma IFN stimulated expression of the cell surface and the nuclear receptors. Induction of NGF receptors in SW1116 cells resulted in internalization and nuclear translocation of 125I-NGF. When NGF bound to the chromatin, ribosomal RNA synthesis was inhibited. Two-dimensional gel electrophoresis of [35S]methionine-labeled chromatin proteins indicated significant changes in chromatin protein composition in cells treated and not-treated with gamma IFN. gamma IFN effectively stimulated the expression of NGF receptors in two colorectal carcinoma cell lines, but inhibited the expression in melanoma and breast carcinoma cells. It is suggested that gamma IFN, by modulating the expression of NGF receptors may affect the NGF-dependent growth of some tumor cell lines.


The insulin receptor and type I IGF receptor: comparison of structure and function. The insulin receptor and type I IGF receptor are closely related in structure and function. The receptors are heterotetrameric glycoproteins, of structure alpha beta beta alpha, which are widely distributed in mammalian tissues. A third member of this receptor family has been described, the insulin receptor-related receptor for which a ligand has still to be identified. It has also been demonstrated that the insulin receptor and IGF receptor form alpha beta beta alpha hybrids in cells expressing both receptors. The key elements in the function of any receptor are recognition of ligand and transmission of an intracellular signal. In the insulin and IGF receptors, determinants of binding specificity are contained within amino-terminal and cysteine-rich domains of the extracellular alpha-subunit. Intracellular signalling is dependent on ligand activated tyrosine kinase activity in the transmembrane beta-subunit, which phosphorylates both the receptor itself and the specific substrate insulin receptor substrate-1 (IRS-1). Phosphorylated IRS-1 binds the enzyme phosphatidylinositol 3-kinase and may act as a multivalent docking site for SH2 domains of other proteins involved in signalling. The possibility that some signalling molecules interact directly with the receptors has not been ruled out. The specificity of action of insulin and IGFs in vivo depends on differences between the respective receptors in tissue distribution, ligand binding specificity and intrinsic signalling capacity. However, the detailed aspects of gene and receptor structure which underly these functional differences are still poorly understood. Moreover, the issue of specificity is complicated by the existence of hybrid and atypical receptors, which in principle could bind and respond to both insulin and IGF-I, although the physiological significance of these receptor subtypes is at present unclear.


Control of transforming growth factor-beta activity: latency vs. activation. Transforming growth factor-beta is a pluripotent regulator of cell growth and differentiation. The growth factor is expressed as a latent complex that must be converted to an active form before interacting with its ubiquitous high affinity receptors. This conversion involves the release of the mature growth factor through disruption of the non-covalent interactions with its pro-peptide or latency associated peptide. The mechanisms for this release in vivo have not been fully characterized but appear to be cell specific and might involve processes such as acidification or proteolysis. Although several factors including transcriptional regulation, receptor modulation and scavenging of the active growth factor have been implicated, the critical step controlling the biological effects of transforming growth factor-beta may be the activation of the latent molecule.


Leukemia inhibitory factor (LIF): a growth factor with pleiotropic effects on bone biology. Historically, growth factors are denominated based on a specific biological activity. In many cases, these factors display a much broader spectrum of activities, especially when their effect is tested on various cell or tissue types. Consequently, names of certain factors are quite deceptive. A textbook example is leukemia inhibitory factor (LIF). LIF was initially described based on its ability to induce differentiation in the murine myeloid leukemia cell line M1. Later, LIF turned out to be a synonym for at least nine different factors defined on the basis of their effects on a variety of cell types including lymphomas, liver cells, embryonic stem cells and carcinoma cells, neurons, melanomas and osteoclasts. Apart from its differential effect on unrelated cell types and tissues. LIF induces biphasic effects on cells of the same "lineage" as well. Needless to say, LIF activity in these circumstances largely depends on the developmental stage of the target cells. An example is LIF activity on bone cells. Osteoclast as well as osteoblast activity is stimulated or suppressed by LIF depending on the developmental stage of the respective cells. This concept is of utmost importance in the evaluation of the seemingly opposing or contradictory effects of LIF in vitro as well as in vivo.


In vivo interactions of TGF-beta and extracellular matrix. TGF-beta, a multifunctional cytokine, plays an important role in embryogenesis and in regulating repair and remodeling following tissue injury. Many of the biological actions of TGF-beta are mediated by widespread effects on deposition of extracellular matrix. TGF-beta stimulates the synthesis of individual matrix components including proteoglycans, collagens and glycoproteins. TGF-beta also blocks matrix degradation by decreasing the synthesis of proteases and increasing the synthesis of protease inhibitors. Finally, TGF-beta increases the synthesis of matrix receptors and alters their relative proportions on the surface of cells in a manner that could facilitate adhesion to matrix. All of these events have largely been demonstrated in vitro in cultured cells. In an experimental model of glomerulonephritis we have shown that TGF-beta is responsible for the accumulation of pathological matrix in the glomeruli following immunological injury. Furthermore, all three of TGF-beta's actions on extracellular matrix--increased synthesis, decreased degradation and modulation of receptors--have now been documented to be involved in matrix deposition in vivo in this model. Administration of the proteoglycan decorin suppressed TGF-beta-induced matrix deposition in the nephritic glomeruli, thus confirming a physiological role for decorin as a regulator of TGF-beta. Inhibitors of TGF-beta may be important future drugs in treating fibrotic diseases caused by overproduction of TGF-beta.


Psychological implications of genetic screening. Providing genetic information about the risk of developing certain conditions or passing them on to children has far-reaching implications for how people act, think and feel with regards to their health and themselves. Not all of these effects are intended or desirable. Likely interventions to reduce some of the adverse effects may include educational programs aimed at the general population as well as those presenting the tests. Legislation to protect the rights of those being tested may also be required. Well-planned studies are needed to document the psychological effects of genetic screening and to determine how the benefits can be maximized and any adverse effects minimized. Unless these data are collected we will have no way of refuting the assertion made over fifteen years ago by Kuhr that the benefits of population-based genetic screening have not been shown to outweigh the psychological costs (Kuhr, 1975).


[Transduodenal sphincteroplasty of the Oddi-Boyden for free bilio-pancreatic flow]. In 58 patients we performed transduodenal sphincteroplasty to show the effectiveness of this procedure in patients with stenosis of the sphincter of Oddi-Boyden, choledocholithiasis and biliary pancreatitis with follow up ranging from 14 months to 11 years 3 months. The sphincteroplasty was performed in 33 cases (27%) for stenosis, in 13 cases (22%) for biliary pancreatitis and in 12 cases (12%) for choledocholithiasis. All cases with the exception of one had cholelithiasis or choledocholithiasis. In 39 patients (67%) the cholangiography performed before the sphincteroplasty demonstrated a common bile duct with average diameter of 1.6 cm. On the first, third and fifth postoperative examination of serum bilirubin and amylase showed a progressive decrease, implying free flow through the common bile duct. Post operative cholangiography confirmed free flow of contrast trough the common bile duct into the duodenum (p < 0.05). The morbidity and mortality were 24.5% and 1.7% respectively. The results were bad in 2 cases, fair in one case, and excellent in 55 cases (94.6%); which were completely free of symptoms postoperatively. We conclude that transduodenal sphincteroplasty of the sphincter of Oddi-Boyden is a useful procedure to reestablish free biliary flow in cases of stenosis, choledocholithiasis and biliary pancreatitis.


[Amebic liver abscess in Tarapoto-Peru]. In order to know the incidence and epidemiologic features of the Amebic Hepatic Abscess we realized this study in the medicine service. 86.67% were males, the average age was 41.38 +/- 18.60 years old being more frequent between 30 and 69 years old (74.48%). The more affected were farmers (60%), students (10%) and Housekeepers (6.67%). The average time of the disease was 12.12 +/- 6.35 dias. The most frequent symptoms were abdominal pain in the upper right quadrant (96.66%), Hepatomegaly (83.33%), Fever (82.22%), Diarrhea (37.77%), Nausea (36.66%), Jaundice (33.33%). The initial diagnosis was AHA (45.55%), acute cholecystitis (14.44%), generalized infectious syndrome (7.77%), acute hepatitis (6.66%). The most frequent studies was: echography (98.85%). AHA alone was in the right lobe (84.05%), left lobe (14.49%). The bigger abscess was of 12 cm in diameter. The treatment was metronidazole + antibioticos (37.78%), metronidazole + antibiotico+percutaneous drainage (24.45%), Metronidazole + surgical drainage (3.33%). The complications were right pleural effusion (8.89%), peritonitis (5.56%) and pioneumothorax (1.11%). The hospitalization time was 14 +/- 8.02 days. There was one death (1.11%). The AHA was ones of each 76 deliveries in our medicine service.


[Oral hydration with rehydration salts in appendectomized patients]. A randomised prospective study of 80 patients to demonstrate if oral hydration with rehydratant salts is as effective as the parenteral infusion for the hydration of patients immediately after appendectomy was performed. The tolerance and conditions of hydration were excellent with 92.5% and 87.5% respectively with oral hydration and with parenteral hydration (p > 0.05). The use of Metronidazole orally with Gentamycetin intramuscular or complication such a wound infection did not influence the hospital stay. With oral hydration, apatite returned sooner, (p < 0.05) patients ambulated sooner (p < 0.05), and the hospital stay was shorter (p < 0.05). In effect our study showed that oral hydration is effective as parenteral immediately after the appendectomy in all stages of appendicitis, this include apendicular abscess and diffuse peritonitis. There was saving of cost, saving of time en administration of fluids and shorter hospital stay in the patient with oral hydration than with the parenteral hydration group.


[Prognostic significance of age in resectable cancer of the stomach]. From January 1, 1966 to December 31, 1991, 137 patients with carcinoma of the stomach underwent standard radical gastrectomy at Belen Hospital, Trujillo, Perú. The patients were classified into two groups--those with age < or = 40 years (n = 19) and those with age > 40 years (n = 118)--and we analyzed herein comparatively clinicopathologic features and five year survival rates using the Mantel Haenszel test. In patients aged 40 years and younger there was a significant increased in the number of patients with carcinomas present in the upper two-thirds of stomach (p < 0.01) and in undifferentiated type adenocarcinoma in histology (p < 0.01) compared with patients more than 40 years old. There were no statistically significant differences between these two groups of age with regard to sex, abdominal mass, size of tumor, type of cancer (early vs advanced carcinoma), Borrmann's criteria, depth of invasion (T), nodal involvement (N), clinical stage (UICC, 1987), type of operation, curability, operative death and five year actuarial survival (8.0 percent vs 6.0 percent, respectively) (p > 0.05). In this study, carcinomas in young people were found to have a higher incidence of undifferentiated forms pathologically and the majority occurred in the body and after gastric resection were similar in both groups of patients.


[Digestive physiology and pathology in high altitude]. In the high altitude environment the oxygen and air density are decreased, the temperature and humidity are low, there es an increase in radioactivity. These environmental factors influence on the human body; it has been known for many years that people born and living at high altitude have different morphological and physiological characteristic than those at low altitude. The digestive mechanism for adaptation or acclimation to high altitude has interested physiologist and clinicians for many years. The objective of this article is to present a brief overview of the digestive physiology and pathology in the high altitude.


[Rules and procedures in the diagnosis and medical (non-surgical) treatment of acute abdomen]. The acute abdomen is due to a medical disorder or surgical problems. Diagnosis is often difficult; acute diseases of the lung, chest, kidney, for example, may closely mimic primary diseases of the abdomen and can masquerade as surgical abdomen. The history assumes overwhelming importance, a careful physical examination is absolutely essential. It is incumbent upon the physician first to decide what is the most likely diagnosis to be correct; and then to undertake treatment indicated for that diagnosis. The laboratory studies, x-ray studies, echography, abdominal paracentesis and other diagnostic approaches may be indicated, when the diagnosis may still be obscure. In the course of the investigation of a patient with acute abdomen, the immediate goals are the correction of dehydration, electrolyte depletion and other problems. It is extremely important that no analgesics or sedatives ever be given until a decision is made as to a proper working diagnosis.


[Hepatitis C].

[Hepatitis C]. The development of specific serological markers for virus C hepatitis makes possible the identification of patients infected with this virus. Epidemiological aspects as well as clinical and therapeutic ones are summarize in this article.


[Gastroenterologic endocrinology: basic aspects]. Gastrointestinal cells produce several substances which act as messengers in the various biochemical processes of the body. These substances are released by endocrine, paracrine and neurocrine mechanisms. Both, hormonal and neuronal phenomenaregulate the absorptive, secretory and motility activity of the gastrointestinal tract. This paper goes over basic and general aspects of hormones secreted in the gastrointestinal system in order to make easier the understanding of their influence in the health and disease.


[Lantibiotics].

[Lantibiotics]. Lantibiotics synthesized by gram positive bacteria (Staphylococcus, Streptococcus, Bacillus, genera) are a special group of polycyclic polypeptides constituted of protein amino acids and unusual amino acids (i.e. lanthionine, beta-methyllantionine etc.) these last ones exhibiting interchain thioeter bridges and ring structures. Some lantibiotics are already used in medical therapy (nisin, gallidermin, epidermin) as well as for food preservation (nisin). Their special structures and synthesis have focused substantial scientific interest, the lantibiotics proving to be ideal experimental models not only for microbiology but also for biochemistry, molecular biology, gene technology and protein engineering in the purpose to get more insights in the fundamental aspects of the cell biology.


Entamoeba histolytica: phylogenetic considerations. A review. Comparison of 16S rRNA sequences alone positions E. histolytica in rRNA-based phylogenies branching after flagellates such as Euglenoids and Kinetoplastids, whereas morphological and functional features had suggested an earlier branching and different relationships. As several characteristics of this parasite do not precisely adjust to the phylogenetic frame obtained by comparison of ribosomal sequences, and the inferences from this approach could be skewed because of the high A+T content of Entamoeba rDNA, a re-evaluation of E. histolytica phylogeny seems convenient at this point. The data about genomic and protein sequences could provide bases to complement or expand the rRNA-based phylogeny.


Subcellular distribution of amebapain, the major cysteine proteinase of Entamoeba histolytica. Amebapain, the major cysteine proteinase of E. histolytica, appears to be important both for digestion and as a cytotoxic factor. By immunocytology we established that amebapain was bound to matrix-like structures both on the cell surface and within subcellular vesicles; the amebapain co-localized with pinocytized iron oxide, suggesting that the enzyme recycles between plasma membrane and pinocytic vesicles. We conclude from these data that (i) the pinocytic vesicles in E. histolytica perform functions that in higher eukaryotes are taken over by specialized organelles such as lysosomes and cytotoxic granules, and (ii) the vesicles contain a matrix that helps retain the protease upon exocytosis of vesicle contents.


Entamoeba histolytica collagen binding proteins. Three main collagen binding proteins from trophozoites of E. histolytica have been isolated: 105 kDa, 56 kDa and 30 kDa. They display a type I collagenolytic activity. The enzyme behaves as a mammalian collagenase regarding to its activity, collagen degradation products and inhibitors. Antibodies against affinity-purified molecules inhibit the binding of trophozoites to collagen substrates. Indirect evidence suggests that the 30 kDa molecule is the putative collagen receptor. These surface molecules may be necessary for attachment and migration of the parasite into solid tissue.


High resolution two-dimensional protein gel evidence of differential gene expression during Entamoeba encystation. As an initial step of investigation into the regulatory mechanisms of encystation in Entamoeba, we compared the protein profiles of newly formed cysts and trophozoites of E. invadens using high resolution two-dimensional PAGE and digitized video image analysis of silver stained gels. A total of 155 proteins unique to trophozoites and a total of 72 proteins unique to cysts were detected. Five of the most prominent cyst specific proteins were identified as candidates for further study. These results imply that extensive changes in gene expression accompany the progression of this parasite through its life cycle.


Collagenase activity in clinical isolates of Entamoeba histolytica maintained in xenic cultures. Several isolates of pathogenic and non-pathogenic E. histolytica from xenic cultures were tested for their capacity to digest native type I collagen gels. The results demonstrate that the pathogenic isolate HM48:IMSS has a high collagenolytic activity. The non-pathogenic isolates, HM43:IMSS, HM44:IMSS and HM46:IMSS showed significantly lower collagenolytic activity. Six groups showing different degrees of collagenase activity or non-activity were separated from the non-pathogenic isolates by a Percoll gradient. The groups obtained from the pathogenic isolate HM48:IMSS always displayed enzymatic activity.


Identification and partial purification of an Entamoeba histolytica membrane protein that binds fibronectin. A 37 kDa protein has been described as a putative receptor for fibronectin (Fn) on E. histolytica trophozoites (1). We have now identified a membrane protein that binds biotinylated fibronectin (BFn) with an apparent molecular weight of 140 kDa. Using BFn we were able to follow this protein during partial purification through DEAE-cellulose and Fn-Sepharose chromatography. Antisera prepared against a peptide corresponding to the deduced amino acid sequence for the putative receptor binding site for human Fn (2) recognized a protein with the same molecular weight. The purified protein was also recognized by this sera. We propose that this protein may function as a Fn receptor and will explore the possibility for it being an integrin.


Fibronectin "receptor" in Entamoeba histolytica: purification and association with the cytoskeleton. Preferential binding of E. histolytica trophozoites to fibronectin (FN) is mediated by a 37 kDa peptide (1). We report now the further purification of this "putative" FN receptor (FN-R) and its characterization as an external membrane component also associated to the cortical cytoskeleton. The FN-R was solubilized from Triton-cytoskeletons and separated by chromatography in FN-Sepharose. The FN-R, labeled when live trophozoites were iodinated with 125I, remained associated to the cytoskeleton together with the FN bound to it, but was removed from the surface by trypsinization. The association of the FN-R to the cytoskeleton was inhibited by cytochalasin D, which also interferes with the adhesion of trophozoites to FN substrates and the organization of actin adhesion plates.


Actin associated proteins of Entamoeba histolytica. Treatment of E. histolytica HM1-IMSS trophozoite extracts to conditions that produce gels of actin and associated cytoskeletal proteins in other ameboid cells caused formation of macroscopic actin rich complexes (ARCs). The one-dimensional PAGE protein profile of this ARC was similar to those of Dictyostelium and Acanthamoeba actin gels. Formation of the E. histolytica ARCs was enhanced by added lipids. In addition to actin, the ARC was enriched with proteins that showed cross-reactivity to antibodies to alpha-actinin and the 50K actin binding protein (elongation factor 1 alpha) from Dictyostelium. E. histolytica ARCs appear to be comprised of a number of actin cytoskeleton proteins and provide a source for their isolation and characterization.


Biochemical analysis of Entamoeba histolytica HM1 strain resistant to complement lysis. In this study, quantitation of several hydrolases and analysis of electrophoretic patterns of E. histolytica HM1 axenic strain periodically exposed to lytic-human serum (lytic-HS), heat-inactivated human (HI-HS) or bovine (HI-BS) sera were performed. The N-acetylglucosaminidase (NAGAse) levels increased in amebas resistant to complement. The acid phosphatase (AP) and proteolytic activity (PA) levels did not vary significantly in all groups of treated amebas, as compared with amebas from axenic cultures. Moreover, amebas exposed to either HI-HS or lytic-HS sera showed a discrete quantitative increase as compared with HI-BS group, in some peptides with a M(r) between 116 and 45 kDa. These results indicate that, besides resistance to complement lysis, exposure of E. histolytica to lytic-HS induces an augmentation in NAGAse levels.


Macrophage colony-stimulating factor enhances the respiratory burst of human monocytes in response to Entamoeba histolytica. Mononuclear phagocytes (MP) are probably the most capable effector cells of the body in the defense against virulent strains of E. histolytica. Killing of E. histolytica by MP appears to involve both oxidative and non-oxidative mechanisms. Thus, in this study we have investigated whether trophozoites of an axenic virulent strain E. histolytica HM1:IMSS (EH) were capable of eliciting an oxidative response in pure populations of freshly isolated human monocytes. Using a luminol-enhanced chemiluminescence assay we demonstrate that these cells produce a strong respiratory burst when challenged with live amebas over a wide range of MP:EH ratios. Furthermore, pre-incubation of monocytes with recombinant Macrophage Colony Stimulating Factor (M-CSF) could further increase the oxidative metabolism of MP in response to E. histolytica. Our results indicate that, in contrast to what occurs with polymorphonuclear leukocytes, the interaction of E. histolytica with MP leads to the production of reactive oxygen intermediates by this cells. The enhancement of this potent microbicidal mechanism by inflammatory cytokines may further increase the amebicidal capacity of human mononuclear phagocytes.


The killing of Entamoeba histolytica by activated human eosinophils. Unlike normal, opsonin aided human eosinophils, fMLP-activated human eosinophils are capable of destroying virulent E. histolytica. Opsonins are not required for this action, although they enhance the effect. Some activated eosinophils succumb in the action as well, probably victims of toxic products released by dying amebas. Activated eosinophils thus appear to resemble activated macrophages in their dealing with this parasite.


Entamoeba histolytica modulates TNF-alpha, IL-1 alpha/beta and c-fos gene expression in macrophages. E. histolytica infections induce a state of transient suppression of cell-mediated immunity. As macrophages are involved in host defense in amebiasis, we determined whether soluble amebic lysates (Eh) can modulate TNF-alpha, IL-1 alpha/beta and c-fos gene expression in naive bone marrow-derived macrophages (BM delta). By Northern analysis, the RNA production of these genes after 0, 0.5, 1 and 3 h exposure to Eh was determined and compared to lipopolysaccharide (LPS) stimulation. In response to Eh, TNF-alpha mRNA was increased two fold while IL-1 alpha/beta RNA levels were increased 6- and 19-fold, respectively. Pretreatment of BM delta with H7, a PKC inhibitor, abrogated Eh induced TNF-delta gene expression and reduced IL-1 alpha/beta gene expression 3.5- to 4-fold over control levels. We conclude that E. histolytica stimulates BM delta to induce TNF-alpha gene expression through a PKC-dependent pathway and IL-1 alpha/beta gene expression partially through PKC and another yet undetermined pathway(s).


Further physicochemical characterization of the monocyte locomotion inhibition factor (MLIF) produced by Entamoeba histolytica. Ultrafiltration, gel-sieve chromatography and HPLC were used to purify MLIF. This material was HCl-hydrolyzed and the amino acids analyzed by HPLC-ortho-ophthaldialdehyde. Two hydrophobic non-polar (ile,leu), two uncharged polar (thr,tyr) and two positively charged (basic) (his, arg) amino acids were found in clear excess to their concentration in AMC and thus may intervene in the composition of MLIF.


Sex differences in systemic and local immune responses to Entamoeba histolytica after intraperitoneal and rectal immunization in Balb/c mice. The antibody responses against Entamoeba histolytica in Peyer's patches and spleen after rectal, intraperitoneal and intragastric immunization with glutaraldehyde-fixed amebas (GFA) was compared between male and female mice by the use of a spot forming cell (SFC) assay. We found that female mice elicit significant higher anti-amebic SFC responses than male mice, in both spleen and Peyer's patches after rectal and intraperitoneal stimulation, whereas by intragastric route females show higher responses than males in spleen but not in Peyer's patches.


Effect of the monocyte locomotion inhibitory factor (MLIF) produced by Entamoeba histolytica upon the respiratory burst of human leukocytes. In addition to inhibiting the locomotion of human MP, MLIF appears capable of inhibiting the respiratory burst (measured by chemiluminescence) of MP and of PMN as well. The effect on the latter cells may or may not be relevant in the host-E. histolytica interaction, as PMN have been found to be notoriously inefficient in dealing with amebas and, foremost, do not use oxidative mechanisms in dealing with the parasite. On the other hand, the inhibitory effect on MP may represent a true evasion mechanism inasmuch as activated MP are capable of destroying virulent amebas, and do so by both oxidative and non-oxidative mechanisms.


Active immunization in hamsters with live Entamoeba histolytica trophozoites of low virulence. Live trophozoites of Entamoeba histolytica of low virulence (LV) were inoculated intraportally in hamsters. One week later they were challenged intrahepatically with highly virulent (HV) trophozoites of the same strain and sacrificed 1 week later. Significant protection manifested by the production of smaller lesions was observed in immunized animals. Antiamebic IgG levels were significantly higher in the immunized group. Histologically, livers of immunized animals presented small lesions containing foamy macrophages, epithelioid cells, fibroblasts and devoid of amebas. Lymphocyte and plasma cell infiltrates were seen periportally.


Kinetics of the anti-amebic antibody producing cells response in Peyer's patches and spleen after both local and systemic stimulation in Balb/c mice. The kinetics of the anti-amebic antibody producing cell (APC) response was analyzed by a spot forming cell (SFC) assay, after a single dose of glutaraldehyde fixed amebas (GFA) by intragastric, rectal and intraperitoneal routes. It was found that mice elicited both local and systemic immune responses in Peyer's patches and spleen, by either local or systemic stimulation. The analysis of the isotype of the anti-amebic APC in mice given four times the GFA by the mentioned routes revealed that mice produced anti-amebic APC of the three major isotypes in both spleen and Peyer's patches.


Identification of a parasite-specific cytoplasmic 67 kDa Entamoeba histolytica antigen recognized by patient sera and monoclonal antibodies. To avoid false positive reactions in tests for anti-ameba antibodies, we wanted to identify parasite-specific component(s). Amebiasis patient sera recognized an antigen of 67 kDa by immunoblotting in an active E. histolytica fraction obtained by ion exchange chromatography. Monoclonal antibodies against the fraction were made. Antibody 3G2 reacted with three antigenic components of 67, 40 and 25 kDa and in the immunocytology with an epitope located in the cytoplasm of E. histolytica trophozoites. ELISAs using the isolated parasite fraction and monoclonal antibody 3G2 (to assay inhibition of binding) were capable of distinguishing specific reactivity in sera from amebiasis patients.


Scanning electron microscopy of erythrophagocytosis by Entamoeba histolytica trophozoites. We analyzed by scanning electron microscopy (SEM) the sequence of erythrocyte ingestion by a virulent strain of Entamoeba histolytica trophozoites. Axenic cultures of amebas were placed in chamber plastic slides for 30 min. Human red blood cells (RBC) were added to the wells in a ratio of 1:100, ameba:erythrocytes. After different times of interaction, cells were fixed and processed for SEM. Erythrophagocytosis by E. histolytica is characterized by random suction of cells at early stages and polarization of the phagocytic event at one end of the parasite during later stages.


Phagocytosis and proteinase activity are not related to pathogenicity of Entamoeba histolytica. To examine the relationship between phagocytosis, proteinase activity and pathogenicity of axenically grown trophozoites of E. histolytica of strain HM-1:IMSS four different cultures were used: 1) a culture preserved in our laboratory for over 4 years, that lost its pathogenicity 3 years ago; 2) a culture passaged several times through hamster liver, that lost its pathogenicity recently; 3) a highly virulent culture supplied by another laboratory; and 4) amebas recovered from hamster liver abscesses caused by the latter culture. Phagocytosis was measured as erythrophagocytosis. Proteinase activity was determined on azocasein. Pathogenicity was defined as the capacity to cause liver abscesses in hamsters. A negative correlation was found between phagocytic activity and pathogenicity, since amebas unable to cause liver abscesses had the highest phagocytic activity whereas those recovered from liver abscesses had the lowest phagocytic activity. The percent of phagocytic amebas increased progressively in all cultures through a 2-month observation period. No correlation was found between the level of proteinase activity and pathogenicity. It is concluded that neither phagocytosis nor proteinase activity are adequate markers of amebic pathogenicity.


A unique cysteine proteinase gene of pathogenic Entamoeba histolytica correlates with virulence. Extracellular neutral cysteine proteinases are an important virulence factor of E. histolytica. Experimental evidence supporting its role in invasion includes the ability to degrade components of the extracellular matrix and activate complement by specifically cleaving C3. We had previously reported the isolation of fragments encoding cysteine proteinase genes from HM-1 (ACP1) and a nonpathogenic strain (REF291, ACP2) by PCR using consensus sequences based on conserved structural motifs of eukaryotic cysteine proteinases. Using similar techniques, we have now identified a third gene encoding a cysteine proteinase which is present in both pathogenic and nonpathogenic strains and have correlated cysteine proteinase specific-mRNA levels with enhanced proteolytic activity and cytopathic effect on a fibroblast cell monolayer, a quantitative assay of virulence.


Effect of intestinal bacteria on the virulence of Entamoeba histolytica. The effect on amebal virulence of Escherichia coli, Clostridium symbiosum and a mixture of lactobacilli was investigated. Amebas from HM1 and HK axenic strains were incubated with a single bacterial strain or lactobacilli for short, intermediate, or long periods and analyzed for their erythrophagocytosis, hemolytic activity and cytotoxicity in vitro and hepatic abscesses formation in vivo. It was found that in vitro virulence was enhanced by all studied bacteria in HK9 but not in HM1 strains, which only showed an increase in cytotoxicity. The virulence in vivo was solely increased in trophozoites of HM1 strain by all tested bacteria.


Early invasive intestinal amebiasis in Mongolian gerbils. Mongolian gerbils were inoculated intracecally with E. histolytica trophozoites cultured monoxenically. During the first hours of interaction an increase in mucus production was observed. Microulcerative mucosal lesions appeared 24 to 72 h post-inoculation. Inflammatory infiltrate and edema of the lamina propria were associated with necrotic foci. At 96 h, the cecal mucosa was normal and live amebas were no longer detected. It is concluded that gerbils are useful as experimental models for studying the early stages of invasive intestinal amebiasis.


cDNA cloning of Entamoeba histolytica histone H3. E. histolytica has an unusual nuclear structure. Although nucleosome-like particles were observed, no information about histones was available so far. In this paper we describe a cDNA clone with significant homology to H3 histones that was isolated from a lambda Zap library of pathogenic E. histolytica. The complete cDNA encodes a 15 kDa polypeptide, which is shorter by one residue than the human homologue. The amino acid sequence has only 69% identity with human H3.3 histone. Our results indicate that this divergence may contribute to the unusual chromatin structure of E. histolytica.


Immediate cell membrane damage produced by Entamoeba histolytica subcellular extracts. The alpha[14C]amino isobutyric acid is a synthetic amino acid with low molecular weight, not incorporated to protein. Chinese hamster ovary (CHO) cells were labeled with this radioactive compound and treated with the amebal subcellular fraction P30 at short times. We detected membrane damage in CHO cells by specific radiolabel release from the first 30 sec of interaction between cell cultures and amebal fraction.


Interaction of various Entamoeba histolytica strains with human intestinal cell lines. The interaction of four pathogenic and three nonpathogenic E. histolytica strains with two human intestinal cell lines (Caco-2 and HT-29) was examined. The adherence of pathogenic and nonpathogenic E. histolytica to these cells was similar, indicating that defective adherence to intestinal cells is not a common feature of nonpathogenic strains. The addition of different carbohydrates confirmed the importance of the galactose-binding lectin of E. histolytica in binding to these intestinal cells. On the other hand, only virulent E. histolytica strains damaged monolayers of intestinal cells. The results indicate that Caco-2 cells and differentiated HT-29 cells are useful models for research of intestinal amebiasis.


Model of intestinal amebiasis: structural and functional lesions to the rabbit colon mucosa by Entamoeba histolytica lysates. Although the events occurring during the initial interaction of E. histolytica trophozoites with the mucosa of the large intestine probably determine the invasion by the parasites, an appropriate experimental model does not exist. To develop such a model we used full-thickness rabbit colon preparations (0.28 cm2) mounted in Ussing-type chambers. Untreated preparations had electrophysiological properties (potential difference, short-circuit current and electrical resistance) similar in magnitude and duration to those reported for stripped colonic mucosa. Exposure to E. histolytica trophozoite lysates for up to 80 min produced dose-dependent lesions in the colon, consisting of: (a) increased decay rates for potential difference, short-circuit current and transmural resistance, and (b) mucosal lesions involving vacuolation at the bases and shortening of epithelial cells, loss of intercellular junctions, destruction of microvilli, and necrosis of interglandular epithelial zones. The specificity and speed of the electrophysiologic effects and their correlation with the microscopic lesions suggest that this new model will help to understand the initial pathogenic events of intestinal amebiasis.


Morphological characterization of experimental amebic liver lesions in gerbils. Gerbils are susceptible to amebic liver abscess (ALA) production under experimental conditions. However, little is known about the histopathological changes that occur during the evolution of the lesion. We analyzed microscopically the sequence of cellular events of ALA in gerbils inoculated intraportally or intrahepatically with E. histolytica. At early stages trophozoites were associated with different degrees of inflammatory reaction. Amebas were also observed in areas devoid of inflammatory cells. Damaged hepatocytes were either related or not to inflammatory reaction. At late stages, lysis of macrophages and epithelioid cells were seen in relation to necrotic tissue and trophozoites. We conclude that amebic liver necrosis in gerbils at early stages may result from lysis of inflammatory cells as shown previously by us in hamsters, but also by direct contact and lytic activity of amebas to hepatocytes. The late destruction and expansion of hepatic tissue necrosis is apparently associated with damage of macrophages and epithelioid cells.


Histological changes during healing of experimental amebic liver abscess treated with metronidazole. Morphological changes during the healing of amebic liver abscess (ALA) in hamsters treated with metronidazole were studied. Animals with ALA of 4 days of evolution were treated orally with metronidazole (5 mg/100 g for 10 days). Liver samples were studied at different times from the beginning of treatment up to 22 days. The resolution of ALA was accompanied by chronic inflammatory reaction, increased number of foamy macrophages and gradual disappearance of the granulomas. Neoformed hepatocytes and blood vessels, and proliferation of biliary ducts were also observed. Foamy macrophages play an important role in the adequate healing of ALA.


Growth inhibition of Entamoeba histolytica by rat colon components. Susceptibility to invasive amebiasis has been suggested to be due to intrinsic amebic factors and/or to such host factors as intestinal microflora, mucus and colonic redox potential. We investigated the effect of rat colon components on the growth of axenically cultured E. histolytica trophozoites. Extracts of rat colon tissue produced a 57% amebic growth inhibition. The main growth inhibitory components were precipitated by 65% ammonium sulfate and were heat-sensitive. These components were partially separated by ultrafiltration and gel filtration chromatography. Thus, we found colonic components (Mr 50-100 kDa) that produced strong growth inhibition (75%). These results suggest that rat colonic products may play an active role in resistance to amebic infection.


The fast release of mucin secretion from human colonic cells induced by Entamoeba histolytica is dependent on contact and protein kinase C activation. The mucus producing colonic cell line, LS174T, was used as a model to study E. histolytica-induced mucin secretion. E. histolytica trophozoites in contact with the mucus layer overlying the LS174T cells and in response to PMA, a protein kinase C activator, and Ca2+ ionophore A23187 which elevates intracellular Ca2+ ([Ca]i), caused a time-dependent (0.25-2.00 h) release of mucin. PKC inhibitors, H7 and staurosporine inhibited E. histolytica (37 and 75%) and PMA (46 and 100%)-induced mucin secretion, whereas in response to Ca2+ ionophore mucin secretion was augmented (56 and 17%). Both PMA and E. histolytica-induced the translocation of the PKC enzyme from the cytoplasm to the membrane fraction with increased enzyme activity. These results suggest that even though mucin secretion can be induced by PKC and Ca(2+)-dependent pathways, E. histolytica evokes the fast release of mucins by a PKC-dependent mechanism.


Bile salts promote adherence-decreasing effect of colonic luminal hydrolases on Entamoeba histolytica. E. histolytica trophozoites cultivated for > 7 h in the presence of glycosidases, produced by a subset of the colonic anaerobic bacteria of healthy humans, and pancreatic proteases show decreased adherence to Chinese hamster ovary epithelial cells. Since activities of the glycosidases are enhanced by bile salts we investigated whether bile salts would enhance the E. histolytica-CHO cell adherence decreasing effects of the luminal hydrolases (glycosidases plus proteases). CHO cell adherence of control trophozoites was 78.4 +/- 1.2% (mean +/- SEM). Incubations with the hydrolases alone for 4 h did not change adherence. Addition of 5.0 mM sodium taurocholate to the hydrolases for 4 h decreased trophozoite adherence to 30.5 +/- 3.2% of that of control trophozoites (p < 0.05). The effect of sodium taurocholate was dose dependent over 0.5-5.0 mM. Four hour incubation with the hydrolases and sodium taurodeoxycholate at 2.0 and 5.0 mM also decreased trophozoite adherence to 25.1 +/- 2.9% and 29.4 +/- 1.7%, respectively, of that of control trophozoites. These findings show that bile salts enhance the effects of luminal hydrolases on E. histolytica trophozoites, decreasing their ability to adhere to epithelial cells.


Inhibition of adhesion process mediated by anti-Entamoeba histolytica specific monoclonal IgA antibodies. Adhesion of trophozoites to target cells in the host intestine is the first of three consecutive steps (adherence, cytolytic effect and phagocytosis) involved in the invasion of colonic tissue by E. histolytica. To investigate the possible participation of the local secretory immune response in the interference with this early host-parasite relationship, we produced IgA monoclonal anti-E. histolytica antibodies to test their capacity for blocking the adhesion process in vitro (MDCK and HT-29 cell lines) and in situ (colonic mucosa from Balb/c mice and gerbils). Results demonstrate that the monoclonal antibodies tested inhibited trophozoite adherence both in vitro and in situ. This suggests that the local antibody response may play an important role in protection against the invasive process in intestinal amebiasis.


Neutral proteinase activities in different strains and clones of Entamoeba histolytica. Correlation with virulence. Although several factors are involved in the invasive behavior of E. histolytica, proteinases seem to play a key role. Different proteinases have been found in virulent trophozoites of this parasite. Cytosols of clones A, 32-1 462-1 and L-6 of E. histolytica exhibiting various degrees of virulence were used to study the activity of trypsin-like, plasminogen activator and cathepsin B neutral proteinases with specific synthetic oligopeptides. Cathepsin-B like activity showed the highest values in highly virulent clone A, which is derived from virulent strain HM1:IMSS. On the contrary, non virulent clones had very low activity. Clone L-6, a non virulent subclone of strain HM1:IMSS, retained some cathepsin B-like activity. Trypsin-like and plasminogen activator assays revealed low activity and no differences between virulent and non-virulent clones were found. It is concluded that the Arg-Arg-thiol proteinase (Cathepsin B-like) is a good virulence marker.


Inhibition of adhesion by monoclonal antibody to 66 kDa surface antigen of Entamoeba histolytica. The adherence of E. histolytica trophozoites to target cells was studied using a monoclonal antibody to a major surface antigen of 66 kDa. Preincubation of trophozoites with monoclonal antibody decreased their ability to adhere to and engulf erythrocytes and destruction of CHO cells. The monoclonal antibody was specific for the 66 kDa antigen which is possibly a major participant in adhesion which precedes other events in phagocytosis and cytopathic effects.


Purification and functional characterization of the 112 kDa adhesin of Entamoeba histolytica. The 112 kDa adhesin of E. histolytica is directly involved in the cytopathogenic activity of the parasite. We describe here the purification of the 112 kDa protein by electroelution and immunoaffinity chromatography using a monoclonal antibody against the adhesin. Two proteins of 70 and 50 kDa were eluted from the immunoaffinity column along with the 112 kDa adhesin. The three proteins were recognized by monospecific polyclonal antibodies against the adhesin. The same peptides (72 and 56 kDa) were also observed after incubation of the purified intact adhesin in diethylamine buffer. Proteins of 112 and 72 kDa were found to have protease activity, evidenced by their ability to degrade gelatin. Our results indicate that the 112 kDa adhesin was specifically broken down into two polypeptides of 50-56 and 70-72 kDa. The significance of this in vivo is as yet unclear. The adhesin has proteolytic activity, which is retained in the 70-72 kDa polypeptide but not in the 50-56 kDa one.


Purification and partial characterization of an hemolytic activity from Entamoeba histolytica. It is generally accepted that hydrolytic and cytolytic amebic components are involved in the pathogenic mechanisms of E. histolytica. We have now identified a lytic activity in two membrane proteins of 23.5 kDa and 25 kDa, which are able to lyse rat erythrocytes. The activity was purified from total homogenates of the virulent strains HM1:IMSS and HM38:IMSS, and the erythrocyte lysis was directly related to protein concentration. The hemolytic activity was heat-sensitive and resistant to reduction by 2-mercaptoethanol. Total amino acid analysis of pure proteins showed a high hydrophobic amino acid content: 36% for 23.5 kDa and 50% for 25 kDa. This hemolytic activity could be related, along with other amebic factors, to tissue damage.


Profile of amebic liver abscess.

Profile of amebic liver abscess. Two hundred cases of amebic liver abscess diagnosed between 1989 and 1991 at the Kasturba Medical College, Manipal were analyzed in this retrospective study. The clinical features and investigation reports were studied and the treatment and its response were analyzed. Amebic liver abscess constituted 0.6% of total hospital admissions during the study period. The male to female ratio was 13:1 with the most common age group of presentation between the fourth and fifth decades of life. Abdominal pain was the most common symptom (92%) and hepatomegaly was observed in 94% of the cases. Ultrasonogram of the abdomen served as the most useful diagnostic aid. Right lobe abscess was observed in 87% of the cases. Abscess was single in 81.5% of cases. Abscess size of more than 4 cm was observed in 46.5% of the cases. Metronidazole and chloroquine were found to be effective in most cases. Aspiration was done in 35.5% of cases. The complications encountered in this study were pleural effusion (two cases), pneumonic consolidation (four cases), pericardial effusion (one case) and ascitis (two cases).