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Biomedical subjects

M Ben-Bassat

Publications and source records attributed to M Ben-Bassat.

At least 19 recordsLinked to original sources
PubMed1994

Uninephrectomy aggravates tubulointerstitial injury in rats with adriamycin nephrosis.

The effects of uninephrectomy on the function and structure of the remnant kidney were assessed in rats with Adriamycin-induced nephrosis, 12 weeks after the injection of Adriamycin. The kidney volume of Adriamycin-treated uninephrectomized rats (NX-AD) was 2.3 times that of sham-operated, Adriamycin-treated animals (SH-AD; p < 0.001). The marked renal enlargement in NX-AD animals was due to the development of large tubular cysts. Following uninephrectomy, the fractional volume of tubular lumen almost doubled (NX-AD, 0.33 +/- 0.02; SH-AD, 0.17 +/- 0.02; p < 0.001) and the absolute volume of tubular lumen increased more than fourfold (NX-AD, 0.51 +/- 0.08 ml; SH-AD, 0.12 +/- 0.02 ml; p < 0.001). The frequency of tubular lumen with a large cross-sectional area (> or = 40,000 microns 2) was 5.8 +/- 1.1% in NX-AD and 0.7 +/- 0.2% in SH-AD groups (p < 0.001). The fractional volume of interstitial fibrosis in NX-AD animals was larger than in SH-AD (0.09 +/- 0.02 versus 0.04 +/- 0.01%, p < 0.05). As opposed to the worsening of tubulointerstitial disease, single-kidney glomerular filtration rate, fractional protein clearance, glomerular volume and the extent of glomerular sclerosis did not differ significantly in NX-AD as compared to SH-AD groups. This study shows that uninephrectomy in rats with Adriamycin nephrosis worsens interstitial nephrosis and aggravates the formation of tubular cysts, leading to a macrocystic kidney disease. These changes are not associated with an increase in glomerular sclerosis.

Animals↗
PubMed1993

Gaucher's disease and mesangiocapillary glomerulonephritis in childhood--a coincidence?

A 6-year-old boy, presenting with a nephritic syndrome, was diagnosed as suffering from Gaucher's disease (GD) and mesangiocapillary glomerulonephritis (MCGN). GD was suspected because of aseptic necrosis of the femoral heads on X-ray and later confirmed by bone marrow aspiration and a lack of glucocerebrosidase activity in white blood cells; MCGN was documented on renal biopsy. The child was treated with prednisone, dipyridamole and aspirin, and recovered completely clinically. A second biopsy was not performed. The connection between these two rare diseases, and between nephritis and GD in general, is discussed.

Basement Membrane↗
PubMed1992

The effect of cyclosporin A on early and late stages of experimental lupus.

OBJECTIVE: To investigate the effect of cyclosporin A (CSA) on the development of lupus in an experimental model. METHODS: Lupus was induced in naive mice following injection of a human anti-double-stranded DNA (anti-dsDNA) monoclonal antibody carrying the 16/6 idiotype (Id). CSA was injected into the mice at an early stage of the disease (2 months after immunization) and at a late stage (4 months after immunization). RESULTS: CSA was found to have a suppressive effect on autoantibody production, as well as on the appearance of other disease manifestations, in the mice with lupus. The effects of the drug were more prominent when the mice were treated at an early stage. This was reflected by a dramatic decrease, to normal levels, in autoantibodies to dsDNA, histones, cardiolipin, Sm, RNP, SS-A/Ro, SS-B/La, and anti-DNA 16/6 Id. Similar effects on the erythrocyte sedimentation rate, white blood cell count, and urinary protein levels were noted. These data were supported by electron microscopy analysis showing a lack of immunoglobulin deposition in the kidneys of mice in which treatment was started early. CONCLUSION: This study demonstrates that, similar to findings in other autoimmune conditions (e.g., insulin-dependent diabetes mellitus), administration of CSA at an early stage in systemic lupus erythematosus may be more beneficial than if the drug is given at a later stage.

Animals↗
PubMed1992

Induction of experimental anti-phospholipid syndrome associated with SLE following immunization with human monoclonal pathogenic anti-DNA idiotype.

MIV-7 is a human monoclonal antibody that binds to DNA and carries a pathogenic anti-DNA idiotype 16/6. The antibody was generated by fusing peripheral blood lymphocytes of a healthy donor which were stimulated with an anti-idiotypic antibody to B11 (a human mAb anti-mouse mammary tumor virus-MMTV). The MIV-7, in addition to being an anti-DNA antibody, also binds to MMTV glycoproteins. Following immunization into the footpad of naive BALB/c mice with MIV-7, the mice developed anti-phospholipid syndrome (APLS) and SLE. The APLS was characterized by thrombocytopenia, the presence of anticardiolipin antibodies, lupus anticoagulant (prolonged APTT), high resorption rate of fetuses and lower mean weights of the placentae and fetuses. The SLE was characterized by serological markers (e.g. anti-DNA), laboratory (increased sedimentation rate and proteinuria) and histological findings (deposition of immune complexes in the glomeruli). Active immunization of mice with mouse monoclonal anti-cardiolipin antibodies led to the induction of primary APLS without SLE. The results add to our previous passive transfer model in which mouse monoclonal anti-cardiolipin antibody generated from immunized mice (CAM) was infused into the tail vein and also resulted in induction of pure APLS [11]. Our results demonstrate the ability to induce secondary APLS to SLE following immunization with a pathogenic idiotype of anti-DNA antibodies and to induce primary APLS with anti-cardiolipin mAb. The existence of these experimental models may permit controlled studies of novel therapeutic models.

Animals↗
PubMed1991

Modulation of SLE induction in naive mice by specific T cells with suppressor activity to pathogenic anti-DNA idiotype.

T cells (CD8+) with specific suppressor activity against anti-dsDNA antibody (16/6 Id+) were generated in vitro. The cells were established from BALB/c-enriched T cells exposed in vitro to silica beads coated with the pathogenic anti-DNA idiotype, 16/6. The idiotype specificity of the suppressor cells was demonstrated by (a) specific induction of a decrease in proliferative response of T helper cell lines specific for the pathogenic idiotype (16/6 Id), when exposed to the idiotype, with no effect on T cell lines with other specificities, e.g., against human IgM or synthetic polypeptide. (b) Effectively suppressing in vitro antibody production of anti-16/6 antibody, employing 16/6-primed B cells and specific helper T cell line. The 16/6 Id-specific Ts cells were found to be MHC restricted. Weekly intravenous injections of 10(7) 16/6 Id-specific Ts cells given to BALB/c mice at different stages of experimental SLE disease prevented the clinical, serological, and pathological manifestations. This effect was characterized by decreased titers of autoantibodies (e.g., anti-DNA, anti-Sm antibodies) in the sera, by abolishment of the proteinuria, leukopenia, and the increased ESR, followed by decreased immunoglobulin deposition in the kidneys. Treating the mice with control IgM-specific T cells did not affect the above parameters. These studies demonstrate the ability to generate Ts cells specific for pathogenic idiotypes. The method might be employed therapeutically to modulate the course of autoimmune conditions.

Animals↗
PubMed1991

The state of leucocyte adhesiveness/aggregation (LAA) in the peripheral blood of burned mice: an early and sensitive inflammatory indicator and a marker of pulmonary leukostasis.

The inflammatory response during thermal injury increases the adhesiveness of white blood cells. A direct slide test was used to compare the state of leucocyte adhesiveness/aggregation (LAA) in the peripheral blood of mice subjected to a thermal injury with the findings in control animals. The state of LAA in the peripheral blood increased from baseline values of 1.1 +/- 1.1 per cent to 6.5 +/- 1.3 per cent within 1 h and to 11.0 +/- 1.2 per cent and 14.8 +/- 4 per cent after 3 and 6 h respectively following thermal injury. The respective leucocyte counts were 3075 +/- 277/mm3 (baseline), 3871 +/- 359, 3840 +/- 687 and 6395 +/- 1152 cells/mm3. The LAA values had subsided by 5 days following burning and correlated with the degree of pulmonary leukostasis. Our study suggests that the LAA is an early and sensitive marker of inflammation and that it can be used as a marker for the presence of pulmonary leukostasis during thermal injury.

Animals↗
PubMed1991

Idiotype specific T-cell lines inducing experimental systemic lupus erythematosus in mice.

Immunization of mice with either antibodies bearing the 16/6 idiotype (16/6 Id) or anti-idiotypic antibodies against the 16/6 Id induces experimental systemic lupus erythematosus (SLE). We report here the establishment and characterization of 16/6 Id-specific T-cell lines from C3H.SW (H-2b) and BALB/c (H-2d) mice. Both lines proliferate specifically in response to the 16/6 Id in an H-2-restricted manner. The injection of 16/6 Id-specific T cells into syngeneic mice led to the development of experimental SLE. Furthermore, inoculation of the 16/6 Id-specific T-cell line derived from C3H.SW mice into the H-2 compatible C57BL/6 mice, which are non-responders to the 16/6 Id, induced experimental SLE. This report provides direct evidence for the role of idiotype-specific T cells in the induction of experimental SLE.

Animals↗
PubMed1990

Primary malignant melanoma in the parotid gland.

Reports of primary malignant melanoma arising from the parotid salivary gland are extremely rare and, to date, have been sporadic. We report a pertinent case, and tabulate and correlate the clinical findings of the 13 cases reported thus far in the literature. The most common symptom is a progressively enlarging, asymptomatic, firm, and fixed mass. Total excision has been the established treatment of choice. The contribution of radiotherapy, chemotherapy, and immunotherapy remains unclear, and it is not possible at present to predict the outcome of treatment in individual patients. Although rare, primary malignant melanoma should be considered in the differential diagnosis of parotid tumors. The clinical significance of establishing the diagnosis of primary malignant melanoma of the parotid gland is emphasized.

Adult↗
PubMed1990

Use of modified fine needle aspiration for study of glomerular pathology in human kidneys.

In routine fine needle aspiration (FNA) of the kidney, the glomeruli are seldom visualized. They appear as multi-layered, cellular conglomerates and, therefore, are unsuitable for morphological analysis. A novel plasma-clot technique for collection of glomeruli from FNA samples was used in a study of 6 native and 24 transplanted human kidneys with suspected glomerular lesions. This technique produced a satisfactory yield of well preserved glomeruli and enabled the identification of glomerular pathology with the accuracy comparable to that of renal core biopsy. The FNA plasma clot method may prove useful in the study of glomerular pathology under conditions where the use of percutaneous biopsy is conventionally limited or avoided.

Adolescent↗
PubMed1990

Castration inhibits glomerular hypertrophy and proteinuria in uninephrectomized male rats.

Renal mass reduction may lead to glomerular hypertrophy, proteinuria and focal glomerulosclerosis (FGS) in humans and rats. In humans and rats, females are less susceptible than males to these phenomena. This study was undertaken to evaluate the effect of male rat castration on the pathogenesis of proteinuria and FGS. Urinary protein was measured in 60-day-old male and female rats. Uninephrectomy was performed in all rats, and castration in half of the males. After 180 days, proteinuria, glomerular filtration rate (GFR) and blood biochemistry were determined. Kidneys were resected, weighed and subjected to morphologic studies. Following uninephrectomy, male rats developed severe proteinuria: 132.3 +/- 40.9 mg 24 h-1, most of which was accounted for by an albuminuria of 70.9 +/- 19.3 mg 24 h-1. In contrast, protein excretion in female and castrated male rats remained within normal limits: 8.0 +/- 1.8 and 4.2 +/- 0.5 mg 24 h-1, respectively. Mean glomerular volume in male rats was 1.18 +/- 0.08 x 10(6) microns3; much higher than in female rats, 0.84 +/- 0.04 x 10(6) micron3, and castrated male rats, 0.87 +/- 0.03 x 10(6) micron3 (P less than 0.005). On light and electron microscopy, glomeruli of female and castrated male rats were completely normal. In contrast, in four of seven male rats, mild glomerular changes were observed. They consisted mainly of mesangial expansion, electron-dense deposits and collapse of capillary loops. These data suggest that castration confers protection against the development of glomerular hypertrophy and proteinuria in uninephrectomized male rats. Endogenous testosterone may be associated with this development.

Animals↗
PubMed1990

The state of leukocyte adhesiveness/aggregation in the peripheral blood of patients with respiratory tract infections.

The state of leukocyte adhesiveness/aggregation (LAA) in the peripheral blood has been employed as a marker of inflammation. In the present study we examined patients with varying intensities of inflammation caused by respiratory tract infections to further investigate the reliability of the state of LAA for the detection and assessment of the severity of disease activity. The study includes 140 controls, 46 patients with upper respiratory tract infection, 30 with bronchitis, 27 with suspicion of pulmonary infiltrate, and 39 with small and 18 with large pulmonary infiltrate. Assessment was based on assuming an increasing severity of inflammation from the 1st to the 6th diagnostic category and by making use of discriminant analysis. It was found that the state of LAA proved to be the best variable to classify the patients into their diagnostic category (F to enter 27), followed by erythrocyte sedimentation rate at the 1st h (F to enter 20.8) and total white blood cell count (F to enter 8.3). These studies were followed by animal experimentation. A highly significant correlation (p = 0.005) was found between the state of LAA in the peripheral blood and the degree of pulmonary leukostasis in a model of endotoxemia in rabbits. These results suggest that the state of LAA is not an epiphenomenon and represents the tendency of the white blood cells to stick to the endothelium which facilitates their migration into the tissues.

Adolescent↗
PubMed1990

Sarcoidosis with oral involvement.

A case of sarcoidosis with bilateral hilar lymphadenopathy and multiple submucosal papular oral mucosa lesions is presented. The clinical signs and symptoms described in this case are not uncommon, and their distinguishing features may expedite accurate diagnosis. Early incisional biopsy of the oral mucosa appears useful for histopathologic proof of the diagnosis.

Acute Disease↗
PubMed1989

Visualization of vascular platelet aggregation by plastic embedding and light microscopy.

Previous studies have indicated that platelets play a role in inflammation and microvascular damage but routine histologic preparations do not permit clear visualization of the platelets in tissues. Plastic embedding was used in this study to demonstrate platelet aggregates in the pulmonary vasculature of mice exposed to complement activation. The degree of platelet aggregation in the excised lungs was graded semiquantitatively in a total of 75 mice. Control Balb/c mice had a mean aggregation score of 0.16 while mice which received 0.3 ml zymosan-activated plasma (ZAP) intravenously (iv) had a score of 2.2. Injection of 0.3 or 0.4 ml of ZAP to which epsilon-aminocaproic acid was added prior to incubation with zymosan resulted in a score of 2.6 or 4.7 respectively. Balb/c (C5 sufficient) and AKR/J (C5 deficient) mice injected iv with 1 mg zymosan had scores of 2.9 and 3.2, respectively. Cobra venom factor (CVF) injected iv to Balb/c mice induced a dose-dependent aggregation. Taken together, these results confirm that complement activation products can mediate intrapulmonary platelet aggregation and they also demonstrate the suitability of plastic embedding for visualization of intravascular platelet aggregates under light microscopy.

Animals↗
PubMed1989

Ultrastructural abnormalities in endoscopically and histologically normal and involved colon in ulcerative colitis.

Twenty colonoscopies (eight complete or almost complete; 12 short) were carried out on 15 patients with ulcerative colitis with the aim of comparing the endoscopic aspects with the light and electron microscopic features in biopsies taken from multiple sites. Patients with severe attacks were examined without prior preparation (two examinations). When the attack was mild to moderate (11 examinations), or the patient was in remission (seven examinations), two saline enemas were given up to 1 h before examination. There was a favorable correlation between the endoscopic and light microscopic features in 94.7% of the biopsies (total number of biopsies, 76). The electron microscope findings greatly exceeded those observed by light microscope and indicated that the major abnormality resides within the colonic epithelial cells. Distinctive ultrastructural changes were present both in apparently uninvolved (endoscopically and histologically) parts of colon and in inactive stages of ulcerative colitis. These findings suggest that colonic mucosal involvement may be universal, persist during clinical remission, and precede the light microscopic findings. They also support the importance of maintenance therapy.

Adult↗