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Biomedical subjects

R Weinstein

Publications and source records attributed to R Weinstein.

At least 163 records · Page 9Linked to original sources
PubMed1972

Estradiol and testosterone secretion by human, simian, and canine testes, in males with hypogonadism and in male pseudohermaphrodites with the feminizing testes syndrome.

The role of the human testis in the production of 17beta-estradiol (E(2)) was investigated by determining the concentration of E(2) and testosterone in peripheral and spermatic vein plasma samples. Specimens were obtained from eight normal men, three men with hypogonadism, and two patients with the incomplete form of the feminizing testes syndrome. For comparison, similar studies were performed in four monkeys, 10 mongrel dogs, and 4 additional dogs who were given 1000 IU of human chorionic gonadotropin/day for 5 days. Plasma E(2) was measured by radioimmunoassay utilizing sheep anti-E(2) serum preceded by ether extraction and thin layer chromatographic separation of plasma steroids. Procedural blanks, which were subtracted from all reported values were 14.1+/-0.74 (SEM) pg for deionized water and 13.1+/-0.66 pg for charcoaladsorbed pooled male plasma. Pooled male and pooled female control plasmas averaged 17+/-0.71 pg/ml and 95+/-6.9 pg/ml, respectively; individual adult male specimens ranged between 8 and 28 with a mean of 18+/-1.4 pg/ml. In the eight normal men, the mean peripheral vein E(2) concentration was 20+/-1.6 pg/ml, while the spermatic vein concentration was 50 times as great, 1049+/-57 pg/ml. All three patients with testicular abnormalities had low spermatic vein E(2) concentrations (160, 280, and 416 pg/ml). Lesser E(2) gradients were found across the simian (3-fold) and canine (approximately 12-fold) testes. Testicular testosterone gradients (human 110-, simian 10-, and canine 77-fold) were greater than the E(2) gradients in all three species. In four dogs, HCG treatment elicited a 6-fold increase in peripheral and a 9-fold increase in spermatic vein testosterone concentrations; however, peripheral and spermatic vein E(2) concentrations did not differ from control values. Spermatic vein E(2) concentrations were > 4600 and 2210 pg/ml (post-HCG) in two patients with the incomplete form of the feminizing testes syndrome. Postorchiectomy, peripheral E(2) and testosterone concentrations fell precipitously in both patients, confirming the major contribution of the testes, in this syndrome, to circulating E(2) and testosterone. These studies provide direct evidence that the human testic secretes estradiol.

Adult↗
PubMedDate not supplied

Does a patient with hereditary spherocytosis qualify for preoperative autologous blood donation?

BACKGROUND: Hereditary spherocytosis (HS) is characterized by osmotically fragile spherocytic red cells (RBCs), mild to moderate hemolysis, and splenomegaly. Little is known about the safety of blood bank storage of HS RBCs. CASE REPORT: A 50-year-old man with mild autosomally dominant HS asked to make an autologous RBC deposit before his scheduled surgery. His RBCs were serially tested for osmotic fragility during 4 weeks of blood bank storage in CPD with adenine-saline. Aliquots of his fresh and 4-week-old RBCs were also labeled with 51Cr for measurement of in vivo survival. The osmotic fragility of the patient's fresh RBCs was normal, with 50-percent hemolysis at approximately 0.43-percent NaCl and a sigmoid lysis curve. Incubated osmotic fragility (24 hours at 37 degrees C) was abnormal, with 50-percent hemolysis at 0.64-percent NaCl. Median survival of his fresh 51Cr-labeled RBCs was moderately shortened at 17.5 days. Osmotic fragility increased during storage, with 50-percent lysis occurring at 0.58-percent and 0.62-percent NaCl after 2 and 4 weeks, respectively. Volunteer normal donor RBCs exhibited 50-percent lysis in 0.48-percent NaCl after 4 weeks. Median survival of the patient's 4-week-old 51Cr-labeled RBCs was severely shortened, at 3.5 days. At surgery, intraoperatively salvaged RBCs demonstrated osmotic fragility identical to that of the patient's RBCs freshly obtained by venipuncture. CONCLUSION: HS RBCs may lose membrane under optimum storage conditions, becoming unsuitable for transfusion at surgery. Intraoperative autologous transfusion may be preferable to preoperative deposit for avoidance of allogeneic RBC transfusion in patients with HS.

Anion Exchange Protein 1, Erythrocyte↗
PubMedDate not supplied

Hospital case management: the path to empowering nurses.

Hospital nursing case management is a client-centered approach to patient care that emphasizes client outcomes and nurse accountability. While nursing case management uses the nursing process, it also promotes patient advocacy throughout the entire episode of illness. By incorporating this model of care, nurses can increase their authority, creativity, and satisfaction in the health care system.

Humans↗