Idiopathic magnesium deficiency in mitral valve prolapse.
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to A Laor.
Explore the source record for details and available documents.
Resting and stimulated whole and parotid salivary composition and flow rate were examined in 63 healthy volunteers. No significant differences were found between the young and old in secretion rates and salivary concentrations of sodium, potassium, calcium, magnesium, and total protein. The activity of amylase in the resting and stimulated parotid saliva was significantly lower in the old.
In 17 critically ill men, low levels of FT4, TT4, TT3 and elevated levels of rT3 and cortisol were found. In spite of the low levels of circulating thyroid hormones, TSH levels of the critically ill men were significantly lower than those of the control group, with no correlations to the high cortisol levels. After iv injection of metoclopramide (MCP), a dopamine (DA) receptor blocker, the TSH and prolactin (Prl) increments in the critically ill patients were significantly lower than in the controls. No correlation was observed between basal cortisol levels and integrated TSH response to MCP. It is suggested that increased DA tone or high cortisol levels are not responsible for the lower basal TSH levels and for the blunted TSH or Prl responses to MCP in the critically ill. High levels of cortisol may be responsible for the altered TT4 peripheral metabolism to TT3 and rT3 in these patients.
Serum, bone and urinary magnesium as well as bone mineral crystal size and perfection were determined in 10 chronic hypercapnic patients with chronic obstructive pulmonary disease. Decreased serum magnesium levels were found. Urinary magnesium excretion decreased while bone magnesium increased. Bone mineral crystal size and perfection decreased.
Serum, lymphocyte and bone magnesium concentrations were determined in 5 alcoholic patients in order to assess their total body magnesium status. Decreased values confirmed the existence of magnesium deficiency in chronic alcoholism. Spinal osteoporosis on X-rays, together with magnesium deficiency and decreased bone magnesium concentration in alcohol-associated osteoporosis match similar findings in involutional osteoporosis.
8 young, untreated, hypomagnesemic patients with a recent onset of high-renin essential hypertension, were treated with 750 mg Mg oxide daily. Only functional (vasospastic) lesions were observed in their retinal vessels. After 3 months of therapy, despite no significant change in blood pressure, complete reversal of the retinal changes was observed. The retinal vascular changes could be attributable to vasospasm secondary to hypomagnesemia since serum Mg levels normalized during treatment.
We performed nerve conduction studies in order to study the ability of nerve conduction data to discriminate between patients with and without a given vascular complication (peripheral vascular disease, coronary disease and retinopathy). All data were processed by discriminant analysis. The nerve conduction studies could discriminate between patients with and without retinopathy, but could not discriminate between those with peripheral vascular disease and those with coronary disease. Our work supports the hypothesis that there is a common pathogenesis of nerve conduction and retinal changes.
A rise in free fatty acids (FFA) and a concomitant decrease in serum magnesium levels were found soon after acute myocardial infarction (AMI) in a group of 5 patients. Magnesium and FFA returned to normal levels within 3 days. No changes in serum FFA and magnesium levels were found in the postinfarction period in 5 patients who were under treatment with propranolol during the time they developed AMI. The linear model, magnesium = f(time, FFA), was investigated according to the stepwise regression-forward selection system. It was found that the magnesium level in AMI is best predicted by the FFA level (inverse correlation). In the period of 0-72 h after infarction, an inverse linear correlation was found to exist between the FFA level and the period of time after infarction.
Lymphocyte Mg concentration was measured in 2 patients with congestive heart failure, on long-term diuretic treatment, and was found to be lower than normal. The patients exhibited prolonged Q-Tc intervals on ECG analysis. During treatment with Mg sulfate, the Q-Tc interval normalized as the lymphocyte Mg approached control values. An Mg-sparing diuretic was added to the therapeutic regimen.
Of 147 young women, aged 17 to 34 years, with signs, symptoms and bacteriological evidence of urinary tract infection (UTI), 23 (15.6%) had an infection caused by coagulase-negative Staphylococcus (coag- neg Staph). All patients with coag- neg Staph UTI were sexually active, in contrast to 84.7% of those with UTI of other causes (one-tailed P = 0.03). The former had a higher rate of vaginal discharge (60.9 vs. 25.8% in the latter group, P = 0.003), but fewer of them used tampons as menstrual protection or oral contraceptives. A high percentage of women with coag- neg Staph UTI had commenced sexual activity recently, as compared with the rest of the group (P = 0.03). In a stepwise logistic regression analysis, the only variables that were significantly associated with coag- neg Staph UTI were vaginal discharge and recent onset of sexual activity.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
In order to identify patients who benefit most from a cardiac rehabilitation program, we studied retrospectively all patients who completed a 3-month comprehensive cardiac rehabilitation program during a 2-year period. Questionnaires regarding physical exercise habits were sent to 122 patients and returned by 117 (96%) of them (53 post-acute myocardial infarction, 50 post-coronary artery bypass surgery, 14 post-infarction and surgery, 2 post-angioplasty). Exercise capacity (subset of 66 patients) improved by 19% after rehabilitation (7.8 +/- 3.1 to 9.3 +/- 2.7 METs, p < 0.0001). Univariate and multivariate analysis identified initial exercise capacity as the only independent variable predicting improvement in exercise performance (inverse relationship) (r2 = 0.24, p < 0.0001). The improvement was not related to age, sex, left ventricular function or time from cardiac event to rehabilitation. Patients recovering from both infarction and coronary artery bypass surgery showed a greater improvement (delta exercise capacity 2.8 +/- 1.4 METs) than patients after myocardial infarction alone (delta exercise capacity 0.8 +/- 2 METs, p < 0.02). Improvement was sustained for up to 2 years after completion of the program.
Despite an exercise electrocardiogram (ECG) positive for ischemia by established criteria, many patients referred for coronary angiography to evaluate chest pain are found to have angiographically normal coronary arteries (NCA). Exercise ECG were analyzed from 27 patients with chest pain and angiographically NCA and 28 patients with chest pain and coronary artery disease (CAD) using univariate and multivariate logistic regression analysis. We derived the following logistic model for the logit probability of CAD: 3 + SEX x 4 - METs x 0.7 + STDV5 x 0.8, where SEX = 0 for female and SEX = 1 for male, METs = maximal estimated work load (metabolic equivalents) and STDV5 = horizontal or downsloping ST depression (mm) in V5. A logit probability > or = 0 identified CAD with a sensitivity of 79% and a specificity of 89%. The model correctly identified 28/36 (78%) patients with CAD, and 7/10 (70%) patients with NCA (correct diagnosis 76%; p < 0.02) in a separate random group of 46 unselected patients with positive exercise tests undergoing diagnostic coronary angiography.
We conducted a nation-wide study of the relationship of myopia with height, weight and body-mass index in order to confirm observations that myopic persons are taller than non-myopes. From a review of the data of 106,926, consecutive male military recruits aged 17 to 19 years, we found that myopia is associated neither with higher stature nor with greater weight. Persons with severe myopia were slightly shorter (172.8 +/- 7.1 cm) and weighed less (62.6 +/- 11.0 kg) than those with mild myopia (173.3 +/- 6.9 cm and 63.8 +/- 10.5 kg respectively), while the non-myopes were taller (173.7 +/- 6.7 cm) and heavier (63.9 +/- 10.2 kg) than the myopes (p = 0.0001). The mean body-mass index was only slightly smaller among the myopes (21.1 +/- 3.1 kg/m2) than among the non-myopes (21.2 +/- 2.9 kg/m2, p = 0.0001).
Explore the source record for details and available documents.
Phototherapy for neonatal hyperbilirubinemia was introduced to our medical center in March 1971. To assess the influence of phototherapy on subsequent cognitive outcome, we compared the intelligence test scores at 17 years of age of subjects born 4 months before and 10 months after the introduction of phototherapy. The intelligence quotient score (mean +/- SE) at 17 years for 84 subjects with severe neonatal hyperbilirubinemia was 108 +/- 2 for those treated by phototherapy and 107 +/- 2 for controls matched for gestational age and birth weight. The confounding effect on intelligence quotient scores of perinatal factors (bilirubin concentrations, gestational age, birth weight, Apgar score) and demographic characteristics (ethnic origin, socioeconomic status, paternal education) was taken into account in a multiple logistic regression analysis by using a General Linear Models procedure. Phototherapy was found to have no independent effect on intelligence quotient scores after adjustment for the effect of confounding factors. We conclude that for full-term newborn infants with neonatal hyperbilirubinemia, phototherapy had neither a beneficial nor an adverse effect on intellectual ability in late adolescence.