摘要:

Nonobese patients with essential hypertension have been reported to be insulin resistant. Because blockade of the reninangiotensin system has been demonstrated to improve insulin sensitivity in hypertensive patients, the authors evaluated the effects of angiotensin-II administration and of angiotensin-converting enzyme inhibition with enalapril on insulin-mediated glucose uptake in normotensive men. The results showed no change in insulin sensitivity with either 0.3 ng/kg/min or 1 ng/kg/min angiotensin-II administration or with enalapril therapy. The authors conclude that neither physiologic amounts of angiotensin-II nor converting enzyme inhibition alter insulin sensitivity in normotensive men.

ISSN:0002-9629    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

Myelodysplastic syndrome is a frustrating disorder, which until recently lacked effective treatment. Patients usually succumb to infection, bleeding complications, or progression to acute leukemia. Recombinant cytokines such as granulocyte macrophage-colony stimulating factor, granulocyte-colony stimulating factor, interleukin-3, and erythropoietin have been used to ameliorate the cytopenias associated with this disease. Small clinical trials in myelodysplastic syndrome patients, using cytokines with myeloid activity (G-CSF, GMCSF, IL-3), have shown consistent elevations in the white blood cell counts with little success in elevating hemoglobin or platelets. Erythropoietin is able to increase the hemoglobin in a small group of myelodysplastic syndrome patients. Future trials using combinations of these cytokines may lead to multilineage effects.

ISSN:0002-9629    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

Human immunodeficiency virus (HIV) is a major cause of immunoincompetence. Whether the virus, itself, accounts for all the deficiency remains in question. Steroids can also influence immune function; glucocorticoids cause immunoincompetence while dehydroepiandros-terone (DHEA) enhances immune function. Changes in the levels of such hormones during the course of HIV illness might result in significant changes in immune competence. The purpose of this study is to investigate whether dehydroepiandrosterone-sulphate (DHEA-S) or cortisol levels correlate with absolute CD4lymphocyte levels. Plasma for cortisol and DHEA-S was drawn from 98 adults with HIV. Of these, 67 had simultaneous CD4levels. Cortisol levels were 12.4 ± 4.6 ±g/dl, DHEA-S 262 ± 142 ±g/ dl, and CD4levels were 308 ± 217/mm3(mean ± SD). Correlational analysis revealed a significant relationship between DHEA-S and CD4levels (r = 0.30; p = 0.01) but not between CD4levels and cortisol (r = 0.11; p = 0.36) or cortisol/DHEA-S ratios (r = 0.17; p = 0.16). When analyzed by clinical subgroups, significant differences were also found with a decrease in DHEA-S levels seen in persons with more advanced illness. The data exhibit a positive relationship between the immune status of patients with HXV-related illness and DHEA, leading to the hypothesis that DHEA deficiency may worsen immune

ISSN:0002-9629    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

The effect of asbestosis on lung volumes was studied in 46 workers by measuring total lung capacity (TLC), forced vital capacity, vital capacity, and residual volume using two standard methods: body plethysmography and radiographic lung area. Nine men had neither irregular opacities of any International Labour Office profusion category nor pleural abnormalities; 9 had pleural abnormalities only, 19 had irregular opacities only; and 9 had pulmonary asbestosis with pleural plagues. Of the 28 with irregular opacities, 18 had moderate or advanced asbestosis (category 2/1 or greater). The radio-graphic method gave a mean TLC of 8.11 L and the body plethysmographic mean was 8.09 L. Thus, the radiographic and plethysmographic methods produced virtually identical mean values for TLC and for residual volume 3.84 L and 3.81 L and residual volume/TLC, 47.3 and 47.3, respectively. Lung volumes measured by body plethysmography and by x-ray area were the same in each of the four radiographic categories of asbestosis. The air trapping and normal or slightly elevated TLC, which characterize asbestosis in men who have smoked cigarettes, are revealed by both methods. The radiographic method, when adequate measures are taken to obtain full inspirations, effectively duplicates the body plethysmographic method but is quicker and simpler, particularly for field studies.

ISSN:0002-9629    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

Unilateral nephrectomy (UNX) is followed by a prompt increase in sodium excretion from the remaining kidney. Recently, an important role for atrial natriuretic peptide (ANP) in mediating the UNX-associated natriuresis has been suggested. The present studies were undertaken to gain insight into the intra-renal mechanisms participating in the post-UNX natriuresis in circumstances in -which the release or the action of endogenous ANP were suppressed by prior removal of the right atrial appendage and by administration of monoclonal anti-ANP antibodies, respectively. In anesthetized euvolemic untreated rats, UNX resulted in a twofold increase in urinary excretion of sodium (from 0.93 ± 0.23 to 2.14 ± 0.34 ±Eq/min; p < 0.03), whereas glomerular filtration rate did not change significantly. Fractional excretion of lithium, an index of proximal tubular handling of sodium, increased from 30.7 ± 3.4% to 39.4 ± 4.0%, and fractional distal reabsorption of sodium decreased from 98.6 ± 0.2% to 96.5 ± 0.4% (both p < 0.006). Neither sham atrial appendectomy nor the administration of nonspecific antibodies affect the natriuretic response of the remaining kidney. The natriuretic response to UNX was abolished in right atrial appendectom-ized rats, as well as in rats receiving anti-ANP antibodies. Post-UNX changes in both proximal and distal tubular reabsorption of sodium were also suppressed in these animals. These observations indicate that ANP may be an important mediator of the natriuretic response to UNX and that the proximal and the distal part of the nephron contribute to the postnephrectomy natriuresis.

ISSN:0002-9629    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

Many studies have shown that vigorous exercise acutely stimulates growth hormone (GH) release but the relative contribution of daily physical activity to maintaining the GH/ somatomedin C (SmC) axis is not known. It has been reported that basal and post-exercise plasma SmC values are higher in physically conditioned young men than in sedentary men of similar age. To assess the effect of severe inactivity on the plasma SmC level, basal concentrations of this hormone were measured in patients with quadriplegia (QP) resulting from spinal cord injury (SCI). Venous blood samples were obtained after overnight fast in 41 QP men, ages 24–66, and compared with 119 healthy men of similar ages. Nonparametric analysis of variance showed SmC to be significantly lower in QP than in healthy men (p < .007). Plasma SmC below 0.35 U/ml in adults usually indicates little or no GH secretion by the pituitary gland. In QP, 46% of plasma SmC values were <0.35 U/ml compared to 24% in the healthy group (p < .02). In both groups, an inverse relationship of SmC and increasing age was observed (p < .01). The data suggest that severe inactivity or SCI tend to cause hyposomatomedinemia. The latter endocrine alteration may contribute to the decrease in lean body mass and muscle atrophy of QP patients, and add further functional impairment to the original neurologic deficit. In addition, hyposomatomedinemia could increase the tendency for pressure sore formation and osteoporosis in SCI patients.

ISSN:0002-9629    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

Thrombotic thrombocytopenic purpura is a clinical syndrome defined by the pentad of thrombocytopenia, microangiopathic hemolytic anemia, fever, and renal and neurologic abnormalities. The pathogenesis of this syndrome remains enigmatic, though appropriate management usually involves plasma administration. The authors report on an alternative therapy, high-dose intravenous immunoglobulin, used in the patient after the failure of plasma-pheresis. The implications and potential applications of this therapy are discussed.

ISSN:0002-9629    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

The authors discuss the unusual intravenous pyelogram (IVP) findings in a patient with blunt abdominal trauma. Although the patient had apparent renal dysfunction, both ne-phrogram and pyelogram were seen clearly after a moderate dose of iothalamate. This may be explained by the fact that the underlying complete obstruction was relieved by his traumatic bladder rupture, prior to the contrast study. Alternatively, evidence of azotemia may be an artifact, resulting from resorption of urea and creatinine after rupture. Thus, the nephro-pyelogram may accurately reflect his renal function.

ISSN:0002-9629    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

Although malignant pericardial effusion is a common complication of malignancy, it is rarely the initial manifestation. A case of a nonsmoking 36-year-old woman who had pericardial tamponade due to malignant pericardial effusion as the initial manifestation of malignancy is presented. Case reports of patients with malignant pericardial effusion as the initial manifestation of malignancy published since 1974 are reviewed. The clinical presentation, histology, and survival of these patients is compared with those cases published prior to 1974. Survival of patients with primary malignancy in the lung who present with malignant pericardial effusion has not improved.

ISSN:0002-9629    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

There are only three prior reports of abnormal thyroid function tests in patients who have received salsalate, the salicylate ester of salicylic acid. The authors report an elderly clinically euthyroid man who had thyroid function tests suggestive of central hypothyroidism while taking salsalate but whose thyroid tests returned to normal after the drug was discontinued. They also studied thyroid function tests, including free thyroxine (FT4) and reverse (T3), in two normal volunteers who took salsalate 750 mg twice daily for 1 week. In the normal subjects, total T4and FT4began to fall within 24 hours after the first dose of salsalate, and remained suppressed for at least 24 hours after the drug was discontinued. This rapidity of effect by salsalate is previously undescribed. There was also a fall in FT4, probably due to the use of diluted serum in the equilibrium dialysis FT4assay. Because FT4measurement using diluted serum or equilibrium dialysis may cause falsely low FT4measurements, the authors believe ultrafiltration may be the only reliable method of measuring FT4in these patients.

ISSN:0002-9629    

出版商:OVID    

年代:1993

数据来源: OVID