The role of tumor necrosis factor-alpha in the pathogenesis of aspiration pneumonitis in rats.

Background: Aspiration pneumonitis is characterized by proteinaceous pulmonary edema and acute infiltration of neutrophils into the alveolar space. This study examined the role of the proinflammatory cytokine, tumor necrosis factor-alpha (TNF-alpha), on the pathogenesis of the injury produced by the different components that may be present in the aspirate, acid, or gastric particles.

Methods: Rats were injured by intratracheal instillation of a vehicle containing acid or gastric particles.

Demonstration of a suppressive effect of inhibin alpha-subunit on the developmental competence of in vitro matured bovine oocytes.

Changes in intrafollicular concentrations of different forms of inhibin (free alpha-subunits and alpha beta dimers) occur during follicle development and may influence the oocyte maturation process. The aim of this study was to investigate the effects of inhibin A and free alpha-subunit (pro-alpha C) isolated from bovine follicular fluid on maturation of bovine cumulus-oocyte complexes, as reflected by their competence for embryo development after in vitro fertilization. Bovine cumulus-oocyte complexes were isolated from ovaries obtained from an abattoir and were cultured for 22-24 h at 38.

Novel selective compounds for the investigation of imidazoline receptors.

Over several years our group has sought to synthesize and identify selective ligands for imidazoline (I) receptors, in particular the I2 binding site. As a consequence, [3H]2-(2-benzofuranyl)-2-imidazoline (2BFI) has proved extremely useful for binding and autoradiographic studies. More recently we have synthesized a BU series of compounds and examined these for their affinities for both I1 and I2 binding sites.

Ellipticity and pulse shape dependence of localised wavepackets.

Atoms in intense, high-frequency laser fields exhibit the remarkable property that they can be stable against ionization. We investigate the structure of stabilized wavepackets for a two-dimensional model hydrogen atom interacting with an intense, high frequency laser pulse as a function of the laser pulse ellipticity and laser pulse rise-time. The computed wavepackets are compared with the corresponding Kramers-Henneberger (K-H) ground states.

A novel function for transforming growth factor-beta1: upregulation of the expression and the IgE-independent extracellular release of a mucosal mast cell granule-specific beta-chymase, mouse mast cell protease-1.

Intestinal mucosal mast cells (IMMC) express granule neutral proteases that are regulated by T-cell-derived cytokines, including interleukin-3 (IL-3) and IL-9, and by stem cell factor (SCF). The IMMC-specific chymase, mouse mast cell protease-1 (mMCP-1), is released in substantial quantities into the blood stream during gastrointestinal allergic responses. We used cultured bone marrow-derived mast cells (mBMMC) to identify cytokines that regulate the expression and extracellular release of mMCP-1.

Ca2+-induced Ca2+ release involved in positive inotropic effect mediated by CGRP in ventricular myocytes.

To investigate the effects and mechanisms of calcitonin gene-related peptide (CGRP) on ventricular contractility, ventricular myocytes isolated from adult rat and mouse hearts were exposed to CGRP. Myocyte contractility was assessed by a video edge motion detector, and the intracellular [Ca2+] transients were measured by a spectroflurophotometer in fura 2-loaded myocytes. CGRP exerted a potent concentration-dependent (10 pM-10 nM, EC50 = 44.

A longitudinal study of maternal serum inhibin-A, inhibin-B, activin-A, activin-AB, pro-alphaC and follistatin during pregnancy.

Maternal serum concentrations of inhibin-A, inhibin-B, activin-A, activin-AB, pro-alphaC-related inhibin forms, total follistatin, steroids and gonadotrophins were measured longitudinally in six normal singleton pregnancies. Maternal venous blood was collected randomly during a spontaneous follicular phase prior to donor insemination, at 5, 7, 9, 11, 16, 20, 24, 28, 32 and 36 weeks after the first missed menses and in the early puerperium. Steroid and gonadotrophin profiles conformed to previous reports.

Measurement of inhibin-A (alpha beta A dimer) during the oestrous cycle, after manipulation of ovarian activity and during pregnancy in ewes.

A new two-site ELISA was validated for ovine plasma and used to measure circulating inhibin-A concentrations during a synchronized oestrous cycle in four ewes and throughout pregnancy in six ewes. Inhibin A concentrations were also determined in four ewes during chronic treatment with a GnRH agonist and after subsequent exposure to pregnant mares' serum gonadotrophin (PMSG) to stimulate ovarian follicular development. Concentrations of FSH, LH, oestradiol and progesterone were determined by radioimmunoassay.

Identification of a Theileria annulata antigen expressed in multiple stages of the parasite life cycle.

In order to identify sporozoite surface molecules which may be involved in invasion and could act as potential vaccine candidates, a number of Mabs were raised in mice against T. annulata sporozoites. These were assayed for their ability to block sporozoite invasion of bovine peripheral blood mononuclear (PBM) cells in vitro.

Histochemical and ultrastructural modification of mucosal mast cell granules in parasitized mice lacking the beta-chymase, mouse mast cell protease-1.

The soluble beta-chymases mouse mast cell protease-1 (mMCP-1) and rat mast cell protease-II are predominantly expressed by intestinal mucosal mast cells (IMMCs) and may promote mucosal epithelial permeability when released during intestinal allergic hypersensitivity responses. To study the function of these chymases, we generated mice with a homozygous null mutation of the mMCP-1 gene and investigated their response to infection with the intestinal nematode Nippostrongylus brasiliensis. Whereas mMCP-2, -4, and -5 were transcribed normally, there was no transcription of the mMCP-1 gene in null (-/-) mice, nor was mature mMCP-1 protein detected in (-/-) jejunal mucosa.

Reactive oxygen species contribute to oxygen-related lung injury after acid aspiration.

Unlabelled: Hyperoxia increases pulmonary damage after acid aspiration. We hypothesize that free radicals play a role in acute lung injury. To examine this hypothesis, we injured rats by intratracheal instillation of acidic isotonic sodium chloride solution (NS) (pH 1.

Effects of active immunization of sheep against an amino terminal peptide of the inhibin alpha C subunit on intrafollicular levels of activin A, inhibin A and follistatin.

Active immunization of ewes against inhibin (IMM) consistently increases ovulation rate but this response is not always accompanied by the expected rise in plasma FSH. Inhibin-related molecules also have local auto/paracrine effects within the ovary and the ovulatory response to IMM could be due to neutralization of one of these effects, independent of changing FSH levels. To investigate this, ovaries were collected from long-term IMM (n = 6) and control (CON; n = 8) ewes killed 48 h after progestagen withdrawal (late follicular phase) and all follicles > or = 3 mm were recovered to determine intrafollicular levels of inhibin A, activin A and follistatin by specific two-site immunoassay and oestradiol and testosterone by radioimmunoassay.

Adrenergic regulation of macrophage-derived tumor necrosis factor-alpha generation during a chronic polyarthritis pain model.

Increases in the levels of proinflammatory cytokines, such as TNF alpha, have been intricately linked with arthritis and the pathogenesis of several models of neuropathic pain. In addition, arthritis (as well as other types of persistent pain) is associated with increased sympathetic activity and alterations of other responses in autonomic nervous activity. Adrenergic regulation of LPS-stimulated TNF production by M phi isolated from rats with streptococcal-cell-wall (SCW)-induced arthritis has been examined.

Contact-angle analysis of intraocular lenses.

Purpose: To present contact-angle measurements of commercially available intraocular lenses (IOLs) in air and in water to facilitate the understanding of how various IOLs might interact in different environments.

Setting: Laboratory.

Methods: Five commercially available IOLs were studied: AMO DuraLens PS-59NB.

Intrasound vibration in the early diagnosis of scaphoid fracture.

A prospective trial was designed to assess the sensitivity and specificity of intrasound vibration for the early detection of scaphoid fracture. We replicated the method described by Finkenburg et al. (J Hand Surg 1993;18A:4-7) in an attempt to corroborate their results.

Differential changes in inhibin A, activin A, and total alpha-subunit levels in granulosa and thecal layers of developing preovulatory follicles in the chicken.

Accumulating evidence implicates inhibins and activins as endocrine and local regulators of follicular development in mammals, and it was recently confirmed that inhibin/activin alpha and betaA genes are also expressed in the avian ovary. To investigate the potential involvement of these proteins in the chicken ovary, thecal and granulosa layers of the four largest follicles (F1-F4) and the most recent postovulatory follicle were collected from hens (10/group) killed 4, 12, and 20 h before the expected time of F1 ovulation. Inhibin A and activin A concentrations of tissue extracts (expressed per mg DNA) were measured using validated two-site enzyme-linked immunosorbent assays; total immunoreactive inhibin alpha-subunit (ir-alpha) was also measured by heterologous RIA (Monash assay).

Modulatory actions of activin-A and follistatin on the developmental competence of in vitro-matured bovine oocytes.

The presence of activin receptors on oocytes and granulosa cells suggests that activin and its binding protein, follistatin, may regulate oocyte maturation. The aim of the present study was to investigate whether activin-A and follistatin can influence the in vitro maturation of bovine oocytes as assessed by their competence to form blastocysts after in vitro fertilization. Bovine cumulus oocyte complexes (COCs) were cultured for 22-24 h at 38.

Alterations in the course of acid-induced lung injury in rats after general anesthesia: volatile anesthetics versus ketamine.

Unlabelled: Pulmonary aspiration of gastric acid is a complication that occurs during anesthesia. The effects of the often used anesthetics on the inflammatory response after aspiration of acid are not known. We examined the effects of three different inhaled anesthetics--halothane, enflurane, and isoflurane--as well as parenteral ketamine, on the associated immediate mortality, alveolar protein leakage, and morphometric changes after intrapulmonary instillation of acidic solution in rats.

Decline in serum follicle-stimulating hormone concentrations alters key intrafollicular growth factors involved in selection of the dominant follicle in heifers.

Declining FSH after a transient rise coincides with selection of a dominant follicle (DF) and atresia of the remaining cohort follicles (subordinates) in cattle. The objectives of this study were to determine 1) whether intrafollicular amounts of inhibins, activin-A, insulin-like growth factor I (IGF-I), and IGF-I-binding proteins (IGFBP) are altered during selection of the first-wave dominant follicle (DF1) and 2) whether these biochemical markers are FSH dependent. Beef heifers received six or eight 6-h injections of saline (controls) or eight 6-h injections of recombinant bovine FSH (1 mg/injection) at 38 to 42 h after estrus (Day 0).

Hyperoxia exacerbates microvascular lung injury following acid aspiration.

Objectives: To examine the effects of an increase in ambient oxygen (O2) concentrations on the extent of inflammatory pulmonary damage following acid aspiration.

Design: Prospective, controlled laboratory study.

Settings: University-affiliated animal research facility.

Analysis of a novel antiinflammatory agent, 1-(7-tert.-butyl-2,3-dihydro-3,3-dimethylbenzo[b]furan-5-yl)-4- cyclopylbutan-1-one (PGV-20229), in plasma matrices by stable-isotope-dilution gas chromatography-mass spectrometry.

A sensitive and selective GC-MS method was developed for the determination of low levels of a novel antiinflammatory agent, 1-(7-tert.-butyl-2,3-dihydro-3,3-dimethylbenzo[b]furan-5-yl)-4- cyclopropylbutan-1-one (I), in small volumes of animal plasma. The method involved the addition of 13C6-labeled-I to plasma samples, followed by a simple liquid-liquid extraction with hexane to isolate the analytes from matrix components.

Effects of supplementary treatment with bovine growth hormone on hormonal and ovulatory responses to inhibin immunization in ewes.

The aim of this study was to determine whether supplementary treatment with recombinant bovine growth hormone(rbGH) can enhance the ovulatory response of ewes to inhibin immunization. Crossbred ewes (n = 20) were actively immunized against bovine inhibin a1-29 peptide conjugate while 20 ewes served as controls. Oestrus was synchronized using progestagen sponges and ewes were allocated to four groups: control ewes (n = 10); control ewes given rbGH (n = 10); inhibin-immunized ewes (n = 10) and inhibin-immunized ewes given rbGH (n = 10).

X-ray intensifying screen visible light detection meter.

A light meter has been designed and built for the purpose of measuring the light emitted from an intensifying screen during x-ray irradiation. The meter uses a photodiode detector with a minimal drift amplification system. The meter repeatability was better than 0.

Activin A and inhibin A as possible endocrine markers for pre-eclampsia.

Background: Inhibin A and activin A are produced by the placenta during human pregnancy. This study aimed to measure circulating concentrations of inhibin A, pro alpha C-containing inhibins, and activin A in the serum of women with pre-eclampsia and of healthy matched control pregnant women, and to establish the molecular-weight forms of circulating inhibin A and activin A in pre-eclampsia.

Methods: In a retrospective cross-sectional study, blood samples were taken from 20 women in hospital with established pre-eclampsia, and from 20 control pregnant women attending antenatal clinics, who were matched for duration of gestation (pre-eclampsia mean 29.