The use of backscattered electron imaging, X-ray microanalysis and X-ray microscopy in demonstrating physiological cell death.

The cytochemical localization of enzymatic activity by means of backscattered electron imaging (BEI) is reviewed and the application of BEI to changes in acid phosphatase and ATPase distribution during physiological (programmed) cell death in Heliothis midgut is explored. Programmed cell death entails the release of nascent free acid phosphatase as extracisternal hydrolase. This shift can readily be detected by means of the atomic number contrast imparted by BEI of the lead phosphatase reaction product, thus enabling the distribution of dying cells to be mapped.

Hormonal regulation of rat Leydig cell cytochrome P-45017 alpha mRNA levels and characterization of a partial length rat P-45017 alpha cDNA.

We have isolated and characterized a P-45017 alpha cDNA fragment from a rat testis library. The partial length rat P-45017 alpha cDNA (1Kb) has high overall nucleotide and deduced amino acid similarity with human and bovine P-45017 alpha cDNA's and contains the conserved tridecapeptide and heme regions, the termination codon and polyadenylation site. Using this rat testis cDNA probe we measured P-45017 alpha mRNA levels of rat Leydig cells from animals treated with hCG.

Two new hormones: prohormone atrial natriuretic peptides 1-30 and 31-67 circulate in man.

Two peptides consisting of amino acids 1-30 and 31-67 of the N-terminal end of the prohormone of atrial natriuretic factor (pro ANF) which vasodilate aortas in vitro, lower blood pressure in vivo, and have natriuretic properties were found to circulate in 54 normal human volunteers. The mean circulating concentration of pro ANF 1-30 was 1861 +/- 87 pg/ml (SEM) while pro ANF 31-67 mean concentration was 1478 +/- 71 pg/ml versus a level of 67 +/- 3 pg/ml for atrial natriuretic factor (ANF). In chronic renal failure their mean concentrations increased to 40,484 +/- 6,929 pg/ml (SEM), 108,566 +/- 16,888 pg/ml, and 348 +/- 81 pg/ml for pro ANFs 1-30 and 31-67 and ANF respectively.

Circadian rhythm of prohormone atrial natriuretic peptides 1-30, 31-67 and 99-126 in man.

Two peptides consisting of amino acids 1-30 and 31-67 of the N-terminal end of the prohormone of the atrial natriuretic factor (pro ANF), vasodilate aortas in vitro, lower blood pressure in vivo, and have natriuretic properties similar to the atrial natriuretic factor (ANF, amino acids 99-126 of the prohormone). It has been recently discovered that pro ANF 1-30 and pro ANF 31-67 as well as ANF circulate in man. To determine if these three peptide hormones have a circadian variation in their circulating plasma concentrations, eight housestaff volunteers were studied on a day when they were in the hospital for 24 hr.

A study of patient acceptance of double-contrast barium enema and colonoscopy. Which procedure is preferred by patients?

To our knowledge, no previous study has addressed the question of which method of evaluation of the lower gastrointestinal tract is preferred by patients, air-contrast barium enema or colonoscopy. Over a four-month period, we asked 189 consecutive patients who had undergone colonoscopy to express their preference for either air-contrast barium enema or colonoscopy. A clear preference for colonoscopy was expressed by our patients in terms of comfort and polyp detection despite higher cost.

Patient preference in upper gastrointestinal studies: roentgenography versus endoscopy.

We prospectively compared roentgenography and endoscopy of the upper gastrointestinal tract in terms of patient acceptance and tolerance. Endoscopy was significantly better tolerated and easier overall for patients. Patients found no difference between endoscopy and radiography with respect to pain or life-style interruption.

Esophageal acid sensitivity in Barrett's esophagus.

Esophageal acid sensitivity was evaluated in 15 patients with Barrett's esophagus and in 15 patients with reflux esophagitis uncomplicated by Barrett's. Patients with Barrett's esophagus had sensitivity to esophageal acid perfusion less frequently than those with uncomplicated reflux esophagitis (66 vs. 100%; p less than 0.

Barrett's esophagus. A prevalent, occult complication of gastroesophageal reflux disease.

A prospective study of patients with symptoms of gastroesophageal reflux was undertaken to determine the prevalence of Barrett's esophagus and reevaluate the diagnostic approach necessary to detect this complication. Endoscopy with mucosal biopsy was performed in 97 subjects. Twelve (12.

Multistep regulation of Leydig cell function.

LH controls Leydig cell steroidogenesis by interaction with specific membrane receptors initiating membrane coupling events. Stimulation of the androgen pathways occurs mainly through cAMP mediated mechanism including LH induced guanyl nucleotide binding, membrane phosphorylation and adenylate cyclase activation. cAMP dependent kinase activation presumably causes phosphorylation of key proteins of the steroidogenic pathway and consequent increase in testosterone production.

Solid-phase gastric emptying in patients with Barrett's esophagus.

Delayed gastric emptying as a pathophysiologic factor in patients with gastroesophageal reflux (GER) is controversial. In order to further evaluate this question, we studied a population with severe reflux, specifically, patients with Barrett's esophagus. Solid-phase gastric emptying was measured in 17 patients and in 17 healthy volunteers using radionuclide imaging.

Biliary dyskinesia with associated high amplitude esophageal peristaltic contractions.

A 60-yr-old woman with recurrent biliary-type pain and pancreatitis was found to have abnormal biliary manometrics. Sphincter of Oddi basal and phasic contraction pressures were significantly elevated. Esophageal manometrics revealed high amplitude peristaltic contractions that were unassociated with chest discomfort.

Expression of an estrogen-regulated protein in rat testis Leydig cells.

Previous studies have demonstrated that the induction of an estrogen-regulated protein precedes the desensitization of microsomal enzymes after in vitro treatment of Leydig cells with hCG or estradiol (E2). This protein is recognized by a monoclonal antibody against an estrogen-dependent protein of mol. wt 28,000 from MCF-7 cells [Science 226 (1984) 445].

Variation in prophylactic antibiotic use in pediatric orthopedic surgery.

Fifty-two pediatric patients undergoing orthopedic surgery were evaluated to determine the pattern of prophylactic antibiotic use. Of the 50 patients receiving antibiotics, 43 patients were given the antibiotic prior to surgery; 38 patients received the drug within two hours prior to surgery. All patients received the postoperative antibiotic for a duration ranging from 2 to 14 days.

Characterization of Leydig cell protein kinase. Further studies in hormone action.

Leydig cell cAMP-dependent protein kinase has been characterized using rapid fractionation and optimal conditions to minimize proteolysis. DEAE-cellulose analysis showed a single Type I peak of cAMP binding and enzyme activity that eluted at 0.1 M KCl.

Esophageal bougienage in symptomatic patients with the nutcracker esophagus. A primary esophageal motility disorder.

A wide variety of therapies have been suggested for patients with painful esophageal motility disorders. In a prospective, double-blind, cross-over clinical trial, we evaluated the effectiveness of mercury bougienage ("placebo," 24 F; "therapeutic," 54 F) in eight symptomatic patients with the nutcracker esophagus (NE). There were no significant differences between the placebo or therapeutic dilators in relation to chest pain, dysphagia, lower esophageal sphincter pressure, or amplitude.