The binding of [(3)H]tyrosyl-PBAN28-33NH(2) to pheromone gland membranes of the moth Heliothis peltigera was investigated. The study describes the development of a pheromone biosynthesis-activating neuropeptide (PBAN) radioreceptor assay and demonstrates the presence of a putative PBAN binding site on the pheromone gland. It also describes synthesis of a radioligand and optimization of binding conditions with respect to membrane preparation, number of gland equivalents, kinetics of ligand binding and composition of the binding solution.
View Article and Find Full Text PDFBackground: The successful application of noninvasive Doppler spectrum analysis has been reported for the hemodynamic assessment of LIMA graft after myocardial revascularization.
Hypothesis: The objective of this study was to assess the utility of transthoracic Doppler echocardiography (TTE) in providing information on LIMA flow in patients after coronary artery bypass graft surgery.
Methods: In all, 22 patients (aged 62 +/- 8 years) with LIMA graft to the left anterior descending (LAD) coronary artery who underwent coronary angiography were assessed using high-frequency (5 MHz) transthoracic Doppler echocardiography.
A new approach for the design and synthesis of pheromone biosynthesis activating neuropeptide (PBAN) agonists and antagonists using the backbone cyclization and cycloscan concepts is described. Two backbone cyclic (BBC) libraries were synthesized: library I (Ser library) was based on the active C-terminal hexapeptide sequence Tyr-Phe-Ser-Pro-Arg-Leu-NH2 of PBAN1-33NH2; whereas library II (D-Phe library) was based on the sequence of the PBAN lead linear antagonist Arg-Tyr-Phe-d-Phe-Pro-Arg-Leu-NH2. In both libraries the Pro residue was replaced by the BBC building unit Nalpha-(omega-aminoalkyl) Gly having various lengths of alkyl chain.
View Article and Find Full Text PDFA radio-receptor assay (RRA) for the insect pyrokinin/PBAN family has been developed. The development involved examination of the ligand (3H-tyrosyl-PBAN28-33NH2)-receptor interaction under various incubation conditions and variations on sex pheromone gland membrane preparation. Application of the RRA for a partial characterization of the putative pyrokinin/PBAN receptor in the pheromone gland of H.
View Article and Find Full Text PDFWe have used perforated patch clamp and Fura-2 microfluorescence measurements to study Ca(2+)-activated Cl- currents in cultured mouse renal inner medullary collecting duct cells (mIMCD-3). The conductance was spontaneously active under resting conditions and whole cell currents were time and voltage-independent with an outwardly rectifying current-voltage relationship. The channel blockers DIDS, niflumic acid, glybenclamide and NPPB reversibly decreased the basal currents, whereas the sulfhydryl agent, DTT produced an irreversible inhibition.
View Article and Find Full Text PDFWe report the discovery of a linear lead antagonist for the insect pheromone biosynthesis activating neuropeptide (PBAN) which inhibits sex pheromone biosynthesis in the female moth Heliothis peltigera. Two approaches have been used in attempting to convert PBAN agonists into antagonists. The first involved omission of the C-terminal amide and reduction of the sequence from the N-terminus in a linear library based on PBAN 1-33NH(2.
View Article and Find Full Text PDF1. The nature of Cl- conductance(s) participating in transepithelial anion secretion by renal inner medullary collecting duct (IMCD, mIMCD-K2 cell line) was investigated. 2.
View Article and Find Full Text PDFInt J Artif Organs
September 1999
The control of intravascular volume (IVV) by continuous on-line measurement of protein concentration would optimise the patients' specific rate of ultrafiltration. To prove the accuracy of a refractometric device, plasma was continuously drawn by haemofiltration during 10 haemodialysis treatments of male patients. Refractometry reflects highly significant changes in the concentrations of filtrate proteins (r = 0.
View Article and Find Full Text PDFWe describe an application of the backbone cyclization and cycloscan concept for the design and synthesis of pheromone biosynthesis activating neuropeptide (PBAN) antagonists capable of inhibiting sex pheromone biosynthesis in Heliothis peltigera female moths. Two backbone cyclic (BBC) sub-libraries were designed and synthesized. The structure of the first sub-library ([Arg27]PBAN27-33NH2, termed the Ser sub-library) was based on the active C-terminal hexapeptide sequence (Tyr-Phe-Ser-Pro-Arg-Leu-NH2) of PBAN1-33NH2, which was found to comprise its active core.
View Article and Find Full Text PDFIt was hypothesized that estrogen-induced cardioprotection is mediated by up-regulation and down-regulation of expression of nitric oxide (NO) and P-selectin, respectively. Published data on circulating levels of the vasodilator NO, atherogenic glycoprotein P-selectin, and lipoprotein-a [Lp(a)] in users of triphasic contraceptive steroids are lacking. A total of 30 healthy women (nonusers, controls) and 82 women using oral triphasic contraceptive steroids (ethinyl estradiol and levonorgestrel: Triovlar, Schering AG) for 18 to 24 cycles participated in this study.
View Article and Find Full Text PDFJ Soc Gynecol Investig
October 1996
Objective: To investigate serum interleukin-2 (IL-2) and soluble interleukin-2 receptor (SIL-2) levels in gestational trophoblastic diseases (GTD).
Methods: Sixty-six patients with GTDs and 23 first-trimester healthy pregnant women (controls) participated in this study. According to the World Health Organization scoring system, GTDs were subgrouped into the following groups: 30 hydatidiform mole spontaneous regression (HMSR), 12 postmolar gestational trophoblastic tumors of high risk (PMHR), 14 low-risk choriocarcinomas, and ten high-risk choriocarcinomas.
Tumour necrosis factor alpha (TNF alpha) concentration was determined by a solid phase immunoradiometric assay in sera of 20 healthy postmenopausal women (reference group), 10 women suffering from postmenopausal bleeding with histologically confirmed cystic glandular hyperplasia, and 10 postmenopausal bleeding patients with histologically confirmed endometrial adenocarcinoma. In cases of endometrial adenocarcinoma serum TNF alpha (157.6 +/- 28 pg/ml) was found to be significantly higher than in controls (80.
View Article and Find Full Text PDFArch Insect Biochem Physiol
July 1992
This study describes the preparation and characterization of a highly specific antiserum to Helicoverpa zea pheromone biosynthesis activating neuropeptide (Hez-PBAN), and the use of this antiserum, in an enzyme linked immunosorbent assay (ELISA), to determine: a) the content of endogenous PBAN in head extracts of male and female Heliothis peltigera; b) the level of PBAN at different developmental stages; and c) the content of PBAN in four different moth species. Cross-reactivity studies revealed that the antiserum is directed mainly toward the N-terminal region of the neuropeptide, and that it exhibits similar binding affinities toward the oxidized and reduced forms of PBAN. Analysis of PBAN content in head extracts of male and female H.
View Article and Find Full Text PDFAn electrochemical measuring system for the recording of transmucosal gastrointestinal potential differences based on silver electrodes with double-junctions and continuous-flow saline bridges is described. Under bioelectrochemical control, a probe can passed from the esophagus via the stomach into the duodenum can be accurately assigned to each of these three segments of the intestine. Measurements are demonstrated and applications discussed.
View Article and Find Full Text PDFObjective: To evaluate beta-endorphin secretion in euprolactinemic cases of luteal phase defect (LPD).
Design: Serial blood samples from the 18th to the 26th day of the menstrual cycle were assayed for beta-endorphin, progesterone (P), estradiol (E2), and prolactin (PRL) in cases of LPD and controls. Diagnosis of LPD was based on determinations of serum P and premenstrual endometrial biopsy.
In rats weighting 230-280 g, the resistance, the protein, and the electrolyte concentration of portal vein blood were measured continuously. At constant electrolyte concentration (Cel) resistance was a true measure of hematocrit. Protein concentration (Cprot) was monitored refractometrically in a continuous stream of filtered plasma.
View Article and Find Full Text PDFA refractometric method was used for the continuous registration of plasma protein concentration in rats during and after 3 and 5 minutes of provoked activity. Simultaneous conductometric measurements of hematocrit (hct) showed that, although both invariably changing in the same direction, the relative change of protein concentration is always less than that of hct: plasma volume changes calculated from the former fall short of those calculated from hct by 34 +/- 23% during the hemoconcentrative period during activity and by 52 +/- 11% during the hemodilutory period after activity. The difference between these figures was significant, thus implying that fluid leaving the circulation during the filtration phase is less rich in protein than that entering it during the absorptive phase of microvascular adjustments.
View Article and Find Full Text PDFA method for continuous plasmapheresis and refractometric determination of the protein concentration of blood circulating in the vascular system of the unanesthetized rat is presented. The method is applied to demonstrate very rapid transvascular fluid exchange during physical activity of the animal, noradrenalin infusions and hemorrhage. Changes of protein concentration are compared with concomitant changes of hematocrit in the hepatic portal vein and the v.
View Article and Find Full Text PDFTotal electrolyte concentrations in portal vein and aortic blood of unanesthetized rats were measured continuously by means of ultrafiltrate conductometry. Portal flow rate and mesenteric venous pressure (pmes) could also be measured. The last could be raised to any desired level by a specially developed portal vein clamp.
View Article and Find Full Text PDFBasic Res Cardiol
January 1985
Blood (3.4-13.5% of blood volume) was pumped in and out of the circulation of rats at different rates and period lengths during continuous measurements of blood conductivity (reciprocally related to hematocrit) and arterial pressure.
View Article and Find Full Text PDFCutaneous leishmaniasis of the classical noduloulcerative variety is endemic in Al-Hassa, Saudi Arabia. In a clinical study in which 56 Saudi patients and 66 non-Saudi patients were examined, it was found that the Saudi patients were considerably younger and had significantly milder disease compared with the non-Saudi patients.
View Article and Find Full Text PDFWhole blood and ultrafiltrate conductivity in the portal vein (as a measure of hematocrit and total electrolyte concentration, Cel, respectively) and arterial pressure of alert rats were measured continuously. Single intraduodenal injections of solutions iso- and hyperosmotic to blood (0.5 or 1 per cent of body weight) produced characteristic changes which were compared with those after the application of water.
View Article and Find Full Text PDFBasic Res Cardiol
January 1984
Short bursts of activity are accompanied by a sharp rise, then a sharp drop, followed facultatively by a tonic rise of pressure in the portal and mesenteric vein. Caval vein and abdominal pressure show only a monophasic rise during activity. The drop of portal pressure immediately after the activity peak can be shown to be passive, due to a fall in portal flow rate.
View Article and Find Full Text PDFBasic Res Cardiol
January 1984
The fluid content of circulating blood was followed continuously by conductometric measurement of large vein hematocrit in the alert rat. Arterial pressure was registered simultaneously. 2.
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