Insertion of a sequence encoding light chain 3 of microtubule-associated proteins 1A and 1B in a pestivirus genome: connection with virus cytopathogenicity and induction of lethal disease in cattle.

Pestiviruses represent the first RNA viruses for which recombination with cellular protein-coding sequences has been reported. As a result of such recombinations cytopathogenic (cp) pestiviruses can develop from noncytopathogenic (noncp) viruses. In the case of bovine viral diarrhea virus (BVDV), the generation of cp mutants is linked to the induction of the lethal syndrome mucosal disease (MD) in cattle.

A B-cell-homing chemokine made in lymphoid follicles activates Burkitt's lymphoma receptor-1.

Secondary lymphoid organs (spleen, lymph nodes and Peyer's patches) are divided into compartments, such as B-cell zones (follicles) and T-cell zones, which provide specialized environments for specific steps of the immune response. Migration of lymphocyte subsets into these compartments is essential for normal immune function, yet the molecular cues guiding this cellular traffic are poorly defined. Chemokines constitute a family of chemotactic cytokines that have been shown to direct the migration of leukocytes during inflammation and which may be involved in the constitutive homing of lymphocytes into follicles and T-cell zones.

A chemokine expressed in lymphoid high endothelial venules promotes the adhesion and chemotaxis of naive T lymphocytes.

Preferential homing of naive lymphocytes to secondary lymphoid organs is thought to involve the action of chemokines, yet no chemokine has been shown to have either the expression pattern or the activities required to mediate this process. Here we show that a chemokine represented in the EST database, secondary lymphoid-tissue chemokine (SLC), is expressed in the high endothelial venules of lymph nodes and Peyer's patches, in the T cell areas of spleen, lymph nodes, and Peyer's patches, and in the lymphatic endothelium of multiple organs. SLC is a highly efficacious chemoattractant for lymphocytes with preferential activity toward naive T cells.

Human apolipoprotein B transgenic mice generated with 207- and 145-kilobase pair bacterial artificial chromosomes. Evidence that a distant 5'-element confers appropriate transgene expression in the intestine.

We reported previously that approximately 80-kilobase pair (kb) P1 bacteriophage clones spanning either the human or mouse apoB gene (clones p158 and p649, respectively) confer apoB expression in the liver of transgenic mice, but not in the intestine. We hypothesized that the absence of intestinal expression was due to the fact that these clones lacked a distant DNA element controlling intestinal expression. To test this possibility, transgenic mice were generated with 145- and 207-kb bacterial artificial chromosomes (BACs) that contained the human apoB gene and more extensive 5'- and 3'-flanking sequences.

Tissue expression studies on the mouse acyl-CoA: cholesterol acyltransferase gene (Acact): findings supporting the existence of multiple cholesterol esterification enzymes in mice.

Cholesterol esterification is involved in the regulation of cellular cholesterol content and has been hypothesized to play a role in important physiologic processes including intestinal cholesterol absorption, hepatic lipoprotein production, and macrophage foam cell formation in atherosclerotic lesions. Although initial studies of the mouse acyl CoA:cholesterol acyltransferase gene (Acact) suggested that its gene product was responsible for cholesterol esterification in most tissues, we observed recently that Acact-/- mice have only tissue-specific reductions in cholesterol esterification. To better understand the role of Acact in cholesterol esterification, we used in situ hybridization and immunoblotting to perform tissue expression studies in wild-type mice.

Establishment of serial persistent infections with bovine viral diarrhoea virus in cattle and sheep and changes in epitope expression related to host species.

A pestivirus was transmitted by contact from a persistently infected (P.I.) bullock to pregnant sheep.

Monocyte chemoattractant protein-1 is sufficient for the chemotaxis of monocytes and lymphocytes in transgenic mice but requires an additional stimulus for inflammatory activation.

Monocyte chemoattractant protein-1 (MCP-1), a chemotactic cytokine, acts in vitro as a chemotactic and activating factor for multiple types of leukocytes. To determine the chemotactic and activating effects of MCP-1 in vivo, we constructed transgenic mice that express human MCP-1 in type II alveolar epithelial cells and secrete it into the bronchoalveolar space. We found that MCP-1 overexpression led to a marked increase in the numbers of both monocytes and lymphocytes that could be recovered by bronchoalveolar lavage.

Labeling of proteins by organometallic complexes of rhenium. (I). Synthesis and biological activity of the conjugates.

We describe herein a totally new pathway for the introduction of rhenium in the form of low oxidation state organometallic complexes covalently attached to various proteins. The synthesis of several rhenium conjugates takes advantage of the specificity of N-succinimidyl esters for amino residues. Conjugation experiments were carried out under various conditions, and analysis of the conjugates was performed by FT-IR spectroscopy.

Endothelin activates voltage-dependent Ca2+ current by a G protein-dependent mechanism in rabbit cardiac myocytes.

1. Endothelin is a vasoactive peptide released from vascular endothelial cells which has potent cardiac inotropic effects. We examined the effect of endothelin on the verapamil-sensitive Ca2+ current (ICa) in enzymatically dispersed rabbit ventricular myocytes.

A truncated form of fibroblast growth factor receptor 1 inhibits signal transduction by multiple types of fibroblast growth factor receptor.

A truncated form of the type 1 fibroblast growth factor receptor (FGFR1) lacking most of its cytoplasmic domain was tested for its ability to inhibit signal transduction by each of three different wild-type FGFRs (FGFR1, 2, and 3). When the truncated FGFR1 was expressed in Xenopus oocytes in excess of each wild-type FGFR, mobilization of intracellular calcium mediated by the wild-type FGFRs was completely blocked. The truncated FGFR did not inhibit signal transduction by the co-expressed platelet-derived growth factor beta-receptor.

Prospective, randomized trial of hypertonic sodium lactate versus lactated Ringer's solution for burn shock resuscitation.

We prospectively randomized 51 adult burned patients on admission to study fluid, electrolyte, and physiologic parameters during burn resuscitation with the use of hypertonic saline (HSL, Na 250 mEq/L, 514 mOsm) or lactated Ringer's solution (LR, Na 130 mEq/L, 268 mOsm). Patients suffered at least 20% total body surface area burns (BSA); the mean BSA injury was 36.7% BSA, with a range of 20 to 74% BSA.

Comparative analysis of monoclonal antibodies against pestiviruses: report of an international workshop.

Thirty-three pestivirus strains were grown in cell culture and characterized by immunostaining with 19 monoclonal antibodies (MAbs) raised against hog cholera virus (HCV), with 42 MAbs against bovine viral diarrhoea virus (BVDV) and with 13 MAbs against border disease virus (BDV). Seven MAbs reacted with all pestivirus strains tested, eight MAbs detected only the seven HCV strains, three detected only the 16 BVDV strains. No MAb was found that was specific for BDV.

Accidental sulfur poisoning in a group of holstein heifers.

Fourteen animals died or were euthanized after toxic levels of elemental sulfur were accidentally fed to a group of 120 Holstein heifers. Dehydration, rumen stasis, tachycardia, and diarrhea were seen along with metabolic acidosis, hypokalemia, and hypochloremia. The majority of deaths occurred from 3 to 10 days after the sulfur was fed to the heifers.

Mechanisms of accumulation of arachidonic acid in cultured myocardial cells during ATP depletion.

Previous studies have suggested that the accumulation of free arachidonic acid may be of major importance in the pathophysiology of myocardial ischemia. The purpose of the present study was to determine if the release of arachidonic acid from myocardial cells was more dependent on the extent of ATP depletion than on the inhibition of fatty acid oxidation. In addition, these studies were designed to determine if arachidonic acid release only occurred when ATP was depleted beyond a critical threshold level.