Specific contribution of different phospholipid surfaces to the activation of prothrombin by the fully assembled prothrombinase.

This paper addresses, in thermodynamic and kinetic terms, the reasons for the acidic lipid specificity of the human prothrombinase complex. We obtained, from the measured lipid titrations of the initial rates of prothrombin activation, the empirical binding constants for prothrombinase assembly on different membranes. These favored assembly on phosphatidylserine (PS)- as opposed to phosphatidylglycerol (PG)-containing membranes.

Interspecific and intrapopulation variation in mitochondrial ribosomal DNA sequences of Mytilus spp. (Bivalvia: Mollusca).

A 560-base pair portion of the mitochondrial 16S ribosomal DNA (16S rDNA) from three morphologically similar mussels, Mytilus edulis, M. galloprovincialis, and M. trossulus, was amplified with the polymerase chain reaction, and 349 base pairs were sequenced.

Sequence analysis of teleost retina-specific lactate dehydrogenase C: evolutionary implications for the vertebrate lactate dehydrogenase gene family.

At least two gene duplication events have led to the three lactate dehydrogenase (LDH; EC 1.1.1.

Influenza A virus-specific cytotoxic T lymphocyte activity declines with advancing age.

Objective: To investigate whether influenza A-specific cytotoxic T lymphocyte (CTL) activity is reduced in elderly compared with younger adults.

Design: Case series comparing outcomes in young and elderly cohorts.

Setting: Saint Louis University Division of Geriatric Medicine.

A unique hypertonic response to hypotonic infusion in the pregnant ewe.

Objective: The purpose of this study was to compare the responses of the maternal ewe to intravenous volume expansion with either sufficient lactated Ringer's solution to elevate maternal venous pressure or sufficient hypotonic fluid to reduce blood osmolality.

Study Design: Chronically catheterized pregnant sheep were intravenously infused over 4 hours with either commercial lactated Ringer's solution (5.55 +/- 0.

Pulmonary effects of exposure to fine fibreglass: irregular opacities and small airways obstruction.

Objective: Man made mineral fibres imitate asbestos and produce tumours of the pleura in animals. To answer the question, Does prolonged exposure to fibreglass adversely affect pulmonary function or produce radiographic abnormalities in human subjects? we studied workers in a midwestern appliance plant where refrigerator doors and previously entire cabinets were insulated with fibreglass sheeting and loose rotary spun fibreglass.

Methods: Spirometry and lung volumes were measured, respiratory and occupational questionnaires were administered, and chest x-ray films were read for pneumoconiosis using International Labour Office (ILO) 1980 criteria in 284 workers with exposure of 20 years or more.

Evolutionary adaptation to different thermal environments via transcriptional regulation.

Populations of the teleost fish Fundulus heteroclitus are subjected to the clinical variation in environmental temperatures that occurs along the eastern seacoast of North America. In concordance with this change in temperature is the clinal variation in the enzyme concentration of the heart-type lactate dehydrogenase (LDH-B; E.C.

Affinity precipitation of proteins by surfactant-solubilized, ligand-modified phospholipids.

The use of ligand-modified phospholipids solubilized in aqueous solution by nonionic surfactant for affinity precipitation of proteins is described. Avidin was precipitated by contact with solutions in which dimyristoylphosphatidylethanolamine (DMPE) functionalized with biotin (DMPE-B) was solubilized in octaethylene glycol mono-n-dodecyl ether (C12E8) solutions. The nonionic surfactant solubilizes the phospholipid in micelles above its critical micelle concentration (CMC) and in small submicellar aggregates below this concentration.

Electroporation: a method for transferring genes into the gametes of zebrafish (Brachydanio rerio), channel catfish (Ictalurus punctatus), and common carp (Cyprinus carpio).

Recombinant plasmids containing the Rous sarcoma virus long-terminal repeat (RSVLTR) promoter linked to either rainbow trout (Oncorhyncus mykiss) growth hormone 1 (rtGH1) or growth hormone 2 (rtGH2) cDNA were linearized and introduced into the fertilized eggs of zebrafish (Brachydanio rerio), channel catfish (Ictalurus punctatus), and common carp (Cyprinus carpio) by both electroporation and microinjection. The latter two species had these rainbow trout constructs (RSVLTR-rtGH1cDNA or RSVLTR-rtGH2) electroporated into both gametes (i.e.

Transfer, expression, and inheritance of salmonid growth hormone genes in channel catfish, Ictalurus punctatus, and effects on performance traits.

We examined expression and inheritance of salmonid growth hormone genes RSVLTR-rtGH1 cDNA and RSVLTR-csGH cDNA, transferred to channel catfish (Ictalurus punctatus) by microinjection. One to 9 copies of the foreign DNA were inserted in either head-to-tail tandem array at single insertion sites or single copies at multiple insertion sites. All P1 transgenic catfish evaluated produced salmonid growth hormone regardless of the construct.

Establishing and maintaining performance claims. A manufacturer's viewpoint.

Performance claims are the vehicle by which a manufacturer communicates the analytic capabilities of its methods to laboratory users and to regulatory agencies. Claims describe the expected performance of an analytic system. To be useful, claims must be meaningful, achievable, and verifiable.

Phenotypic and functional similarities between 5-azacytidine-treated T cells and a T cell subset in patients with active systemic lupus erythematosus.

Objective: Antigen-specific CD4+ T cells treated with DNA methylation inhibitors become autoreactive, suggesting a novel mechanism for autoimmunity. To test whether this mechanism might be involved in systemic lupus erythematosus (SLE), phenotypic markers for the autoreactive cells were sought.

Methods: Cloned normal T cells were treated with the DNA methylation inhibitor 5-azacytidine (5-azaC) and studied for altered gene expression.

Molecular phylogeny of the prickly shark, Echinorhinus cookei, based on a nuclear (18S rRNA) and a mitochondrial (cytochrome b) gene.

The classification of the sharks is unclear. This is particularly true for the superorder Squalomorphii. The relationships between the squalomorphs and other superorders of sharks and the relationships between the different orders within the squalomorphs are a matter of debate.

Nucleotide sequence of the 18S ribosomal ribonucleic acid gene from two teleosts and two sharks and their molecular phylogeny.

The 18S rRNA sequence was determined for two teleostean fish species, Fundulus heteroclitus and Sebastolobus altivelis, and two sharks, Squalus acanthias and Echinorhinus cookei. To study the molecular phylogeny of these taxa, the sequences were compared with 18S rRNA sequences of the Coelacanth Latimeria chalumnae, the frog Xenopus laevis, and humans. Maximum parsimony analysis of the sequences resulted in a single most parsimonious tree that is in agreement with the expected phylogeny.

Age-related changes in LFA-1 expression, cell adhesion, and PHA-induced proliferation by lymphocytes from senescence-accelerated mouse (SAM)-P/8 and SAM-R/1 substrains.

Accelerated senescence-prone mice of the SAM-P/8jf series were compared with senescence-resistant SAM-R/1 controls in terms of age-related changes in phytohemagglutinin (PHA) proliferative responses and lymphocyte function-associated antigen-1 (LFA-1) utilization by non-adherent splenocytes. Advancing age was associated with a reduction in cell proliferative responses to PHA in both substrains, although the rate of decline was significantly more rapid in the senescence-prone animals. Conversely, in both substrains there was a progressive age-related increase in the proportion of splenocytes expressing high levels of LFA-1, and a parallel increase in the degree of LFA-1-dependent cell aggregation induced by phorbol ester.

Ribosomal RNA sequences and the diversity of symbiotic dinoflagellates (zooxanthellae).

Zooxanthellae are unicellular algae that occur as endosymbionts in many hundreds of common marine invertebrates. The issue of zooxanthella diversity has been difficult to address. Most zooxanthellae have been placed in the dinoflagellate genus Symbiodinium as one or several species that are not easily distinguished.

Mivacurium infusion during nitrous oxide-isoflurane anesthesia: a comparison with nitrous oxide-opioid anesthesia.

Study Objective: To determine the potentiation of the neuromuscular blockade induced by a titrated infusion of mivacurium in the presence of isoflurane versus a nitrous oxide (N2O)-opioid anesthesia.

Design: An open-label, controlled study.

Setting: The inpatient anesthesia service of two university medical centers.

Reduced infectivity of cold-adapted influenza A H1N1 viruses in the elderly: correlation with serum and local antibodies.

Objective: To compare young and elderly adults in terms of their immune responses and rates of infection following intranasal vaccination with a live attenuated influenza virus.

Design: Time series, comparing outcomes in young and elderly convenience sample.

Method: Retrospective laboratory analysis of serum and nasal wash specimens collected during prior studies in which young or elderly volunteers had been inoculated with cold-adapted influenza A/Kawasaki/86 (H1N1) reassortant virus.

Effect of hypoalbuminemia and parenteral nutrition on free water excretion and electrolyte-free water resorption.

Objective: To measure the effect of human albumin supplementation during parenteral nutrition on serum albumin concentrations, colloid oncotic pressure, free water clearance, electrolyte-free water resorption, and sodium excretion.

Design: Prospective, randomized, controlled trial.

Setting: Tertiary care center.

Platelet-activating factor stimulates phosphoinositide turnover in neurohybrid NCB-20 cells: involvement of pertussis toxin-sensitive guanine nucleotide-binding proteins and inhibition by protein kinase C.

Platelet-activating factor (PAF) is an unusually potent phospholipid known to be produced by neuronal cells and to modulate cerebral blood flow and metabolism. In previous studies with NCB-20 cells, we reported that PAF induced a significant mobilization of intracellular free Ca2+ ([Ca2+]i), which was inhibited by PAF antagonists. The increase was the result of release from intracellular stores and influx from extracellular sources.

Erythropoietin in preeclampsia.

To investigate the possible effect of preeclampsia on erythropoietin metabolism, we measured plasma and urine erythropoietin concentrations and complete blood count in 19 women with preeclampsia and nine healthy gravidas. Hemoglobin concentration and hematocrit values in the preeclamptic patients did not differ significantly from those of the normal pregnant controls. However, the plasma erythropoietin concentration tended to be higher in the preeclamptic group than in the normal pregnant controls (26.

Fetal cardiovascular and fluid responses to maternal volume loading with lactated Ringer's or hypotonic solution.

To determine whether elevations in maternal vascular pressures or reductions in maternal osmolality would promote fluid transfer to the fetus, we intravenously infused either lactated Ringer's solution or diluted (hypotonic) lactated Ringer's solution continuously over 4 hours into late-gestation pregnant sheep. During the Ringer's solution infusion, the increases in maternal arterial (20.7 +/- 1.

Evidence of lactate dehydrogenase-B allozyme effects in the teleost, Fundulus heteroclitus.

The evolutionary significance of protein polymorphisms has long been debated. Exponents of the balanced theory advocate that selection operates to maintain polymorphisms, whereas the neoclassical school argues that most genetic variation is neutral. Some studies have suggested that protein polymorphisms are not neutral, but their significance has been questioned because one cannot eliminate the possibility that linked loci were responsible for the observed differences.