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Biomedical subjects

M Ben-Bassat

Publications and source records attributed to M Ben-Bassat.

At least 37 records · Page 2Linked to original sources
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↗
PubMed1988

Instability of leukocyte aggregation: lack of evidence for leukoembolization during various states of inflammation.

This study centers on the question of whether the phenomenon of leukocyte aggregation, which is typical to inflammatory conditions, is pathogenic per se. We examined patients and laboratory animals in whom the presence of aggregated leukocytes in the peripheral blood was documented by direct visualization and where, despite the presence of aggregated leukocytes, neither the patients nor the laboratory animals showed clinical or pathological evidence for leukoembolization. Our in vitro findings about the reversibility of the phenomenon of leukocyte aggregation help to explain the above-mentioned observations as well as the well-known daily clinical experience that, despite complement activation and other aggregatory stimuli, there is no clinical or pathological evidence for leukoembolization.

Aged↗
PubMed1988

Induction of a systemic lupus erythematosus-like disease in mice by a common human anti-DNA idiotype.

Systemic lupus erythematosus (SLE) is considered to be the quintessential autoimmune disease. It has not been possible to induce SLE in animal models by DNA immunization or by challenge with anti-DNA antibodies. We herewith report a murine model of SLE-like disease induced by immunization of C3H.SW female mice with a common human monoclonal anti-DNA idiotype (16/6 idiotype). Following a booster injection with the 16/6 idiotype, high levels of murine anti-16/6 and anti-anti-16/6 antibodies (associated with anti-DNA activity) were detected in the sera of the immunized mice. Elevated titers of autoantibodies reacting with DNA, poly(I), poly(dT), ribonucleoprotein, autoantigens [Sm, SS-A (Ro), and SS-B (La)], and cardiolipin were noted. The serological findings were associated with increased erythrocyte sedimentation rate, leukopenia, proteinuria, immune complex deposition in the glomerular mesangium, and sclerosis of the glomeruli. The immune complexes in the kidneys were shown to contain the 16/6 idiotype. This experimental SLE-like model may be used to elucidate the mechanisms underlying SLE.

Animals↗
PubMed1988

Theophylline prolongs survival and decreases renal damage in female NZB/W F-1 mice.

Theophylline (Th) augments suppressor T cell activity (STCA). We attempted to test this immunoregulatory effect of TH on survival, renal disease and several immunologic parameters in NZB/W F-1 female mice. The median survival was 274 +/- 50 days for the mice receiving Th and 235 +/- 39 days for the controls (p less than 0.01). Assessment of the extent of renal damage by light microscopy revealed activity scores of 1.86 +/- 2 and 4.71 +/- 2.7 for the Th and control groups, respectively (p less than 0.001). T cell activity of NZB/W F-1 lymphocytes was assessed by the local xenogeneic GVH reaction. The mean GVH reaction volume of the Th group was significantly lower (9.3 +/- 8.8 mm3) as compared to controls (31 +/- 9 mm3) (p less than 0.001). The proportion of Lyt-1 versus Lyt-2 spleen lymphocytes did not change significantly. It is concluded that Th prolongs survival and decreases the extent of renal damage in female NZB/W F-1 mice.

Animals↗
PubMed1987

Surgical treatment of livedo vasculitis.

Surgical treatment for livedo vasculitis as a primary approach is not mentioned in the literature. A young female patient suffering from livedo vasculitis (atrophie blanche) was admitted with huge ulcerations and pre-ulcerative, infarcted skin areas of both feet and ankles. The lesions were promptly excised and skin grafted with excellent results. The course of treatment, including several surgical procedures, is described.

Adult↗
PubMed1987

Effect of long-term aluminum administration on the renal structure of the rat.

Kidneys of patients on hemodialysis therapy often undergo structural changes leading to acquired cystic disease. A wide variety of chemical compounds are known to induce experimental renal cystic disease. Since aluminum intoxication has been implicated in the development of encephalopathy, osteomalacia and anemia in uremic patients, this study was designed to investigate whether aluminum administration to normal rats could induce renal morphological changes. Male Wistar rats were divided into three groups; Animals of the Low-dose aluminum (LDA) group received 0.2 mg/day of aluminum, animals of the high-dose aluminum (HDA) group received 2 mg/day of aluminum; the third group consisted of controls (C). Aluminum was injected intraperitoneally as aluminum chloride (6 days a week). 13 weeks later, the kidneys were removed and examined by light and electron microscopy. The findings on eight-microscopic examination were normal in all groups. Electron-microscopic examination was unremarkable in the C and LDA group. In HDA rats, ultrasections of the cortex and outer medulla showed changes in the proximal tubules with increased size and number of lysosomes, osmiophilic granular material inside the lysosomes, vacuolisation of organelles and mitochondrial damage of varying degree. No cystic changes were found.

Aluminum↗
PubMed1987

An epidemic of suicide attempts by burning in a psychiatric hospital.

Three patients attempted suicide by burning in one ward of a psychiatric hospital in a period of less than 1 month. No such attempts had occurred there in the previous 9 years. The three patients were schizophrenics with depressive features who occupied the same room in the ward. It seems reasonable to suggest that at least the choice of method and the timing of these suicide attempts were influenced by imitation. Hospital staff should be especially aware of the influence of imitation in suicide in order to avert such undesired epidemics.

Adult↗
PubMed1987

Multiple myeloma presenting as anaplastic carcinoma. The role of electron microscopy in the diagnosis.

A tumor excised from the ninth right rib of a patient with chest pains was diagnosed independently by two pathologists as anaplastic carcinoma. Light microscopy of the tumor cells found in the sternal bone aspiration biopsy did not contribute to the diagnosis. When the cells were examined with a transmission electron microscope, the diagnosis of multiple myeloma was established and proved by suitable laboratory tests. Following treatment according to the M2 protocol, the patient is presently in an excellent condition. This case indicates that the electron microscope may serve as an important tool for the diagnosis of diseases difficult to clarify with the light microscope.

Aged↗
PubMed1987

Transcutaneous electrical stimulation of the normal rabbit joint.

To determine the effect of transcutaneous electrical stimulation on the rabbit joint, we studied skin and intraarticular temperatures and pressure both before and following the stimulation in nine rabbits. An elevation in skin temperature by a mean of 0.6 degrees C (p less than 0.05) and increase in intraarticular temperature by a mean of 0.8 degrees C (p less than 0.01) was noted following the electrical stimulation. Intraarticular pressure in the stimulated joints has only a trend to increase, but not significantly. In four other rabbits, synovial tissue of the stimulated joint showed blood vessels congestion and interstitial edema. These results suggest that the analgetic effect produced by electrical stimulation on joints may partially involve intraarticular temperature and pressure alterations.

Animals↗
PubMed1986

Late metastases (beyond ten years) of cutaneous malignant melanoma. Literature review and case report.

A case of late metastasis of a primary malignant melanoma of the sole of the foot after a disease-free interval of 13 years in a premenopausal woman is presented. The clinicopathologic findings are described, and the literature concerning late metastases (beyond 10 years) of melanoma is reviewed. Only seventeen documented cases have been previously reported, to which we add our own case. Sixteen of these eighteen cases concerned premenopausal women. This phenomenon suggests that female gonadal hormones may exert an inhibitory effect on cutaneous melanoma, hence lengthening the disease-free interval.

Adult↗
PubMed1986

Primary malignant melanoma of the vermilion of the lower lip.

A 30-year-old man with primary nodular, rapidly growing malignant melanoma of the vermilion of the lower lip is described. The tumor was excised with wide tumor-free margins and an Abbe-Estlander reconstruction was carried out. The literature on oral melanomas has also been reviewed with special attention given to melanoma of the lip which is extremely rare (31 reported cases). This case is highly unusual in two respects: the melanoma was a nodular type, level 5, while nearly all melanomas reported previously have been superficial with slow radial growth; it was a small lesion arising on the vermilion and not an extension from the cutaneous junction or oral mucosa.

Adult↗
PubMed1986

Oligozoospermia, asthenozoospermia, and sperm abnormalities in ex-addict to heroin, morphine, and hashish.

A 40-year-old male had been addicted to heroin, morphine, hashish, and other narcotics for 12 years. At examination, 2 years after abstinence from drugs, his semen analysis revealed oligozoospermia, asthenozoospermia, and morphologically abnormal spermatozoa such as "round-headed" and "kinked"--sperm with neck abnormalities and immature forms. There was no evidence of other morphological abnormalities or of the presence of morphologically normal sperm. A possible correlation is discussed between the long-lasting drug addiction and morphological sperm abnormality, endocrinological function, karyotype, and immunological status.

Adult↗
PubMed1986

Proteinuria in benign nephrosclerosis.

Benign nephrosclerosis seldom is associated with significant proteinuria or reduced renal function. This study demonstrated that, despite the finding of benign nephrosclerosis on a renal biopsy specimen, concomitant proteinuria is predictive of a poor prognosis. Twelve patients, ranging in age from 24 to 59 years, with hypertension, proteinuria (greater than 1 g/d), and findings of benign nephrosclerosis on renal biopsy specimens were studied retrospectively. In three of these patients, the hypertension and proteinuria were diagnosed during pregnancy. Follow-up was possible in 11 patients. Nine patients became nephrotic in the course of their disease. Two patients had endstage renal disease and required maintenance dialysis treatment. Seven patients had decreased renal function as shown by the increase in serum creatinine levels. Thus, the combination of hypertension, proteinuria (greater than 1 g/d), and benign nephrosclerosis may be indicative of a progressive condition with a high percentage of patients having renal failure.

Adult↗
PubMed1985

Amphotericin B causes aggregation of neutrophils and enhances pulmonary leukostasis.

The influence of amphotericin B (AmB) on the aggregation of polymorphonuclear leukocytes (PMN) was examined by means of in vitro aggregometry as well as in an in vivo model of pulmonary leukostasis (PL). The AmB caused a dose-dependent aggregation of PMN that was partially blocked by addition of serum to the drug prior to its reaction with the PMN. No aggregation of PMN was seen after the addition of nystatin, a similar polyene antibiotic. In vivo studies were conducted in rabbits, where PL was induced by an intravenous infusion of zymosan-activated plasma (ZAP) or phorbol myristate acetate (PMA), and the degree of resulting leukostasis was expressed as the number of PMN per high power field (HPF). Animals in the control group had 6 +/- 3 PMN/HPF. This number increased to 12.4 +/- 5.6 when ZAP was infused and postmortem examination was performed 1 h later and to 17.4 +/- 4 if the examination was performed after 24 h. These numbers increased more than twice when AmB (1 mg/kg) was infused together with the ZAP. Increased PL after the infusion of ZAP and AmB was not attenuated by prior administration of methylprednisolone (30 mg/kg) to the animals. Infusions of AmB per se caused no significant PL but did cause increased pinocytosis in the pulmonary endothelium. Enhancement of PL by AmB was also examined in a model of PMA-induced PL.(ABSTRACT TRUNCATED AT 250 WORDS)

Amphotericin B↗