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Biomedical subjects

Y Maaravi

Publications and source records attributed to Y Maaravi.

17 recordsLinked to original sources

Mortality in the Jerusalem 70-year-olds longitudinal study: does nifedipine have a role?

BACKGROUND: Short-acting nifedipine was found to be associated with increased mortality in elderly patients in some studies. METHODS: We examined effects of long-acting nifedipine in a longitudinal study of Jerusalem 70 year olds (448 participants). RESULTS: After follow-up of 6.5 years (1990-1996) 70 subjects died. We examined the effects of baseline variables on total mortality. Hypertensives had higher mortality than normotensives, 21.2% versus 13.8%, p = 0.01. Diuretic-treated patients (n = 72), mostly hypertensive (n = 71), had significantly higher mortality than non-diuretic-treated patients (n = 375), 45.5% versus 14.1%; p < 0.001. Although nifedipine-treated patients had a higher prevalence of coronary heart disease diagnosis than diuretic-treated patients (52% versus 35%), their relative risk of mortality was 0.8 (CI 0.4-1.4) of that of diuretic-treated patients. A multiple logistic regression model, including gender, systolic blood pressure, creatinine, cholesterol, diagnosis of congestive heart failure, cardiovascular arrest, diabetes, previous myocardial infarction, physical activity, nifedipine, other calcium channel and beta blockers and diuretics, found only serum creatinine and diuretic therapy associated with total mortality, p = 0.004 and p < 0.02, respectively. When interaction terms were added to account for drug combinations, diuretic therapy lost significance, but the combination of diuretics and beta blockers (probably representing a more severe form of hypertension) became significant, p = 0.03. CONCLUSION: Long acting nifedipine is not associated with increased mortality in elderly hypertensives.

Aged

Inhibition of concanavalin A-induced acute T cell dependent hepatic damage in mice by hypothyroidism.

AIMS/BACKGROUND: Concanavalin A (Con A) activates T lymphocytes and causes acute T-cell-mediated hepatic injury in mice. Decreased thyroid hormonal production is associated with a variety of immunological manifestations, including inactivation of macrophages with reduced TNF production and reduced soluble IL-2 receptors in the serum. We have recently shown that hypothyroidism prevents the development of cirrhosis and also minimizes hepatic damage in rats with fulminant hepatic failure. In the present study we examined the effects of hypothyroidism on a mouse model of Con A induced T cell-mediated acute hepatitis. METHODS: Hypothyroidism was induced both medically (MMI, PTU) and surgically. Eight groups of 10 mice each were studied: euthyroid controls (2 groups: water, Con A) and hypothyroid (6 groups: MMI, PTU, Surgical, MMI-Con A, PTU-Con A, Surgical-Con A). RESULTS: Hepatic inflammation was significantly decreased in each of the Con A treated hypothyroid groups of mice. The serum transaminases, TNF-alpha and IL-6 levels were significantly elevated in the Con A treated group while near normal levels were found in the hypothyroid Con A treated groups (mean+/-SE AST: 1499+/-18 vs 78+/-10 IU/l, p<0.001; TNF: 2500+/-250 vs 135+/-15 pg/ml, p<0.001, IL-6: 12,200+/-300 vs 1260+/-140 pg/ml, p<0.001, respectively). CONCLUSIONS: Hypothyroidism, independent of the mode of induction, can effectively inhibit the development of acute T cell-mediated liver damage in mice. These results suggest that some decrease in thyroid function might have a role in the prevention of immune mediated liver diseases.

Alanine Transaminase

Methimazole slows hepatocyte streaming in rats.

Hepatocytes are hypothesized to continually stream from the portal tract to the terminal hepatic vein. By this model, when a cell divides, one of its progeny replaces the dividing ancestor and the other is displaced into a more remote location. The present experiment aims to demonstrate that hypothyroidism affects liver cell turnover. Thirty male adult rats were divided into two groups. One received methimazole for two weeks and the other served as control. Each rat was injected intraperitoneally with 18.5 KBq [3H]thymidine/g body weight. Rats were killed after 1 hr and two and four weeks. Autoradiography was done. The distance of the labeled cells from the portal tract was measured. The mean TSH levels of the methimazole-treated group and controls were 1.45 and 0.25 mM/liter, respectively (P < 0.01). Hepatocyte streaming was lower in hypothyroid (1.8 microns/day) than in untreated rats (2.5 microns/day) (P < 0.01). The respective labeling indices 1 hr after labeling were 0.9% and 1.24% (P < 0.05). We conclude that hypothyroidism diminishes hepatocyte and littoral cell turnover and slows down their streaming.

Animals

Anti-thyroid drugs decrease mucosal damage in a rat model of experimental colitis.

BACKGROUND: Methimazole, an anti-thyroid drug, was recently found to be useful in the treatment of systemic lupus erythematosus and other autoimmune diseases. Moreover, decreased thyroid hormone production is associated with a variety of immunological manifestations, such as reduced activation of CD4+ cells, increased CD8+ cell activity and reduced soluble IL-2 receptors. In the present study we examined the effects of methimazole and propylthiouracil on a rat model of experimental colitis. METHODS: Colitis was induced by intracolonic administration of 30 mg trinitrobenzene sulphonic acid (TNB). Two weeks prior to induction of colitis, rats were treated by either methimaziole (0.04%) or propylthiouracil (0.01%) in drinking water after a week of free access to water. Rats were sacrificed 48 h or 7 days after induction of colitis. The colon was isolated, rinsed with ice-cold water and weighed. Damage was assessed both macroscopically and microscopically and myeloperoxidase (MPO) activity determined. RESULTS: All treated rats were hypothyroid as manifested by a significant elevation of thyroid stimulating hormone (TSH), by comparison with the control groups (mean -1.82 +/- 0.40 versus 0.11 +/- 0.02 mmol/L, respectively). The inflammatory response elicited by TNB resulted in severe mucosal damage 48 h after damage induction, which persisted for 7 days. Pre-treatment with either methimazole 0.04% or propylthiouracil 0.01% significantly decreased mucosal damage macroscopically (lesion area, lesion score and segmental weight) microscopically and also significantly decreased MPO level at both time points (P < 0.01). CONCLUSIONS: Methimazole and propylthiouracil significantly reduce mucosal damage and colonic weight in a rat model of colitis. The mode by which they do so remains to be studied.

Animals

Laboratory reference values for the 70 year olds.

Reference values for common laboratory tests were determined as part of a cross-sectional survey of 70 year olds in Jerusalem in 1991. Subjects were systematically chosen from electoral lists. They were extensively interviewed regarding demographic, socioeconomic and health characteristics. Subsequently, 456 underwent a thorough medical examination including hematologic, biochemical and endocrinologic testing. Analysis of disease-specific mortality and hospital morbidity at 3 year follow-up proved these subjects to be representative of the overall Jerusalem Jewish population of 70 year olds. Test-specific reference subgroups were determined to exclude effects of known diseases and drug consumption. Reference values in these subgroups differ significantly from reference values currently used for adults without regard to age. The determination of disease for subjects provided the opportunity to identify changes that might reflect normal aging and those that might be affected by subclinical pathology. Interpretation of laboratory testing of older adults must consider the age-related differences in reference values.

Aged

The nutritional status of 70 year olds in Jerusalem.

Inadequate nutrition is a major problem of elderly people today, a rapidly growing segment of western societies. Yet information on the nutritional state of the elderly in the community is much needed. We surveyed the nutritional status of a cohort of 70 year olds living in western Jerusalem. A total of 605 persons were interviewed in their home regarding socioeconomic variables, education, self-assessed global health status, use of medicines, and activities of daily living (ADL). In the second stage, a subsample of 463 of the above attended an outpatient geriatric clinic where a medical history was taken and a physical examination, a cognitive test, a psychological profile, blood and urine tests, electrocardiogram, pulmonary function tests, and grip strength measurement performed. Most of the sample population lived at home. Twelve percent reported having severe financial problems. Approximately 14% exhibited some cognitive problems, 83% were totally independent in ADL, and only 15% were housebound with 2.5% being bedbound. Body mass index (BMI) of < 19 kg/m2 was found in 1.1% of the population, while obesity, defined as a BMI > 30 kg/m2, was found in 13.5% of males and 28.6% of females. Polypharmacy was prevalent. A quarter of the study population were taking three or more prescription drugs. Serum triglycerides were below the normal limit in 7.3% of males and 4.7% of females, while total serum cholesterol concentrations were low in 13.9% and 4.7% of males and females respectively. Serum albumin was found below the lower limit of normal (35 g/l) in 16.9% of females and 11.4% of males. The significance of these results, their relation to other nutritional surveys, and their implications for the future are discussed.

Activities of Daily Living

Hemodynamic effects of hypothyroidism induced by methimazole in normal and portal hypertensive rats.

Portal hypertension is accompanied by a hyperdynamic circulatory state that shares some similarities with thyrotoxicosis. This study was conducted in order to investigate the hemodynamic effects of hypothyroidism in a rat model with portal hypertension induced by partial portal vein ligation (PVL). Four groups of 10 rats each were studied: normal control and hypothyroid rats, and PVL control and hypothyroid rats. Hypothyroidism was induced by methimazole 0.04% in drinking water. Hemodynamic measurements were performed using the radioactive microsphere technique. Induction of hypothyroidism was confirmed by elevated TSH levels. In the PVL groups, hypothyroidism ameliorated the hyperdynamic circulation. Portal venous inflow and portal pressure dropped significantly: 7.1 +/- 0.2 vs 4.8 +/- 0.3 ml/min/100 g body wt (P < 0.01) and 13.4 +/- 0.9 vs 10.9 +/- 0.8 mm Hg; (P < 0.01), respectively. In normal rats, hypothyroidism was manifested by a hypodynamic circulatory state. These results demonstrate that hypothyroidism induced by methimazole is followed by amelioration of the hyperdynamic circulation, normalization of portal venous inflow, and reduction of portal pressure.

Animals

Somatostatin-receptor imaging of medullary thyroid carcinoma.

In-111 pentetreotide scintigraphy of 10 patients with residual or metastatic medullary thyroid carcinoma is described. Six patients had sporadic tumor and 4 had MEN IIB. Foci of increased tracer uptake were observed in 9 patients: in the thyroid bed (4 patients), the mediastinum (3 patients.), the shoulder area and left lower abdomen (1 patient), and the left upper abdomen (1 patient). The 10th patient had no abnormal uptake. CT confirmed 2 mediastinal lesions and 2 out of 3 thyroid masses, but did not detect the thyroid remnants or the lesions in the shoulder area and abdomen. Lung lesions < or = 1 cm in diameter and ill-defined liver foci (2 patients) were seen on CT, but not on scintigraphy. Small liver metastases not demonstrated on CT or on scintigraphy were identified at surgery in a MEN IIB patient. Elevated urinary epinephrine was found in 2 out of 4 MEN IIB patients. In one, tracer uptake in the left adrenal corresponded to a mass on CT, to pathological uptake of MIBG and DMSA, and to a tumor removed at surgery. The second patient had peritoneal spread of malignant pheochromocytoma (at surgery), but negative CT and only a single focus in the left lower abdomen on scintigraphy. Somatostatin-receptor imaging is useful for the detection of residual and recurrent medullary thyroid carcinoma, and may identify pheochromocytoma in MEN IIB patients.

Adrenal Gland Neoplasms

A unique presentation of lymphoma of the colon.

Non-Hodgkin's lymphoma often involves the gastrointestinal tract, but primary lymphoma of the colon is rare. Primary lymphoma of the colon masquerading as inflammatory bowel disease is even rarer. We report a patient with an initial diagnosis of Crohn's colitis, who later appeared to have had non-Hodgkin's lymphoma of the colon. We review the diagnosis and treatment of this rare disease.

Adult

Multiple brain abscesses caused by Streptococcus bovis.

A case of multiple brain abscesses caused by Streptococcus bovis in a 28-year-old man is described. Infected bronchiectasis is presumed to be the source of infection. Streptococcus bovis infection is a rare cause of brain abscess. The aetiology and manifestations of this infection are discussed.

Adult

Partial resistance to anticoagulation after streptokinase treatment for acute myocardial infarction.

This study examines the response of 3 different groups of patients to anticoagulants: 50 patients previously treated with streptokinase for acute myocardial infarction (AMI) (group 1), 24 patients with AMI who had received anticoagulants without prior thrombolysis (group 2) and 11 subjects who received anticoagulants for noncoronary indications (group 3). No significant differences were detected between groups 2 and 3; therefore, they were combined for analysis. After streptokinase, patients required 37,755 +/- 1,516 (mean +/- standard error of the mean) U of heparin per day to achieve the desired activated partial thromboplastin time (APTT). The dosage was 30,294 +/- 1,089 U/day in patients without antecedent thrombolysis (p less than 0.001). Group 1 patients required 5 +/- 0.4 days until adequate anticoagulation was achieved, compared with 3 +/- 0.2 days in the control group (p = 0.01). Despite higher heparin requirements, group 1 patients had a lower APTT value than the other subjects (87 +/- 5 vs 101 +/- 6 seconds, p = 0.08). Group 1 patients required 5 +/- 0.3 days to reach anticoagulation with warfarin versus 4 +/- 0.2 days in groups 2 + 3 (p = 0.05). Comparison of groups 1 and 2 yielded similar, although smaller, differences. Patients treated with streptokinase for AMI seem to be partially resistant to anticoagulation, which may increase the risk of reocclusion.

Anticoagulants

Cerebrovascular accident and myocardial infarction associated with anticardiolipin antibodies in a young woman with systemic lupus erythematosus.

A 26 year old woman with systemic lupus erythematosus, including malar rash, photosensitivity, and arthritis, developed a cerebrovascular accident and acute myocardial infarction. High titres to antinuclear factor, anti-DNA antibodies, positive Venereal Disease Research Laboratory (VDRL) test, and anticardiolipin antibodies were found in her serum. A possible association between the presence of anticardiolipin antibodies and the two major thrombotic events is discussed.

Adult