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C Schneider

Publications and source records attributed to C Schneider.

At least 19 recordsLinked to original sources
PubMed1992

cDNA sequence analysis of an antibiotic dodecapeptide from neutrophils.

The full-length cDNA of a neutrophil antibiotic dodecapeptide has been cloned by reverse transcription/PCR from bovine bone marrow RNA. This peptide was originally isolated from bovine neutrophils, and shown to exert a potent antimicrobial activity in vitro on both Escherichia coli and Staphylococcus aureus. The cDNA codes for a polypeptide of 155 amino acid residues with a predicted mass of 17,629 Da and a pI of 8.03. The deduced sequence comprises a putative signal peptide of 29 amino acids, a 114 residue pro-region, and a carboxy-terminal dodecapeptide corresponding to the mature antibiotic. The pro-sequence displays extensive identity to corresponding regions of other structurally unrelated antibiotic peptides of bovine neutrophils recently cloned.

Amino Acid Sequence↗
PubMed1992

cDNA cloning of the neutrophil bactericidal peptide indolicidin.

A structurally novel, tryptophan-rich antimicrobial tridecapeptide amide, named indolicidin, has recently been purified from bovine neutrophils (Selsted et al. (1992) J. Biol. Chem. 267, 4292-4295). Here we describe the molecular cloning of this endoantibiotic, which is synthesised in bone marrow cells as a 144 amino acid residue precursor. The encoded protein has a predicted mass of 16479 Da and a pI of 6.51. A putative signal peptide of 29 amino acids precedes a 101 residue pro-region. The mature peptide is at the 3' end of the open reading frame. A glycine, not found in purified indolicidin, is present at the carboxyl terminus of the deduced sequence and is very likely involved in post-translational peptide amidation.

Amino Acid Sequence↗
PubMed1992

The growth arrest-specific gene, gas1, is involved in growth suppression.

This report describes the structure of the mRNA, the protein product, and the growth-regulating activity of one of the growth arrest-specific genes, gas1. From the predicted amino acid sequence, in vitro translation of gas1 mRNA, and immunofluorescence of cells in culture, it appears that the gas1 protein is an integral plasma membrane protein whose expression is linked to growth arrest. When gas1 is overexpressed from a constitutive promoter in quiescent cells, the serum-induced transition from the G0 to the S phase of the cell cycle is inhibited without affecting the normal early serum response. Ectopic expression of the gas1 gene by microinjection in normal and transformed NIH 3T3 cell lines with the notable exception of SV40-transformed 3T3 cells leads to inhibition of DNA synthesis. Thus, gas1 appears to be one component of a negative circuit that governs growth suppression. Its effect is, however, abolished in SV40-transformed cells.

3T3 Cells↗
PubMed1992

Localization of growth arrest-specific genes on mouse chromosomes 1, 7, 8, 11, 13, and 16.

Growth arrest in NIH3T3 cells is associated with increased expression of a variety of mRNAs, several of which have been isolated as cDNA clones. Six of these growth arrest-specific (Gas) genes were mapped by following the inheritance of DNA restriction fragment length variants (RFLVs) associated with them in panels of recombinant inbred (RI) strains of mice and in the progeny of backcrosses both between laboratory mouse strains and between a laboratory strain and Mus spretus. The six genes are unlinked. Gas-1 maps to Chromosome (Chr) 13, Gas-2 to Chr 7, Gas-3 to Chr 11, Gas-4 to Chr 16, Gas-6 to Chr 8, and Gas-10 to Chr 1.

3T3 Cells↗
PubMed1992

Effects of the prodrug loperamide oxide, loperamide, and placebo on jejunal motor activity.

This crossover, double-blind study investigated the effects of single oral doses of the prodrug loperamide oxide, which is reduced gradually to loperamide in the intestine, and loperamide on jejunal motor activity in 12 fasting healthy men. Five minutes after a phase III of the migrating motor complex (MMC), 2 mg loperamide oxide, 4 mg loperamide oxide, 4 mg loperamide, or placebo were administered. Thereafter, motor activity 10-30 cm abroad the ligament of Treitz was recorded with five catheter orifices at 3-cm intervals over 4 hr. Number of contractions and area under curve increased significantly with 4 mg loperamide and 4 mg loperamide oxide, the increases with loperamide oxide occurring more gradually. Placebo and 2 mg loperamide oxide had no discernible effects. With both 4 mg loperamide and 4 mg loperamide oxide, phase I of the MMC was slightly prolonged and phase II and the time from drug administration to the onset of the first phase III slightly shortened. The percentage of aborally propagated contractions in phase II increased with all active treatments, whereas the occurrence of phases III was not altered.

Administration, Oral↗
PubMed1992

Immunogenicity of free synthetic peptides corresponding to T helper epitopes of the influenza HA 1 subunit. Induction of virus cross reacting CD4+ T lymphocytes in mice.

Four linear synthetic peptides corresponding to residues 12-29, 50-67, 121-138 and 131-147 of the HA 1 subunit of H3 subtype influenza virus (NT/60/68) were tested for their capacity to elicit in vivo peptide-specific CD4+ T cells cross reacting with whole virus. By studying the in vitro peptide proliferative response of lymph node cells from mice sensitized in vivo with free peptides emulsified in complete or incomplete Freund adjuvant, it was found that region 12-29 could be recognized by CD4+ T lymphocytes in the context of H-2k and H-2b, region 50-67 in association with H-2b and region 121-138 in the context of H-2d MHC molecules. Outbred OF 1 mice could recognize regions 50-67 and 121-138. Peptides 50-67 and 121-138 are of potential interest for synthetic vaccine design since they induced in BALB/c (peptide 121-138) and OF 1 (both peptides) mice a CD4+ T cell population that cross reacted with whole virus. The region 50-67 is of particular interest since only few substitutions have been found in this area in natural variants of the H3 virus subtype.

Amino Acid Sequence↗
PubMed1992

Purification and functional characterization of bovine RP-A in an in vitro SV40 DNA replication system.

The single-stranded DNA binding protein RP-A is required in SV40 DNA in vitro replication. The RP-A purified from calf thymus contains 4 polypeptides with molecular weights 70kDa, 53kDa, 32kDa, and 14kDa. The p70 subunit and its proteolysed form p53 are recognized by the monoclonal antibody 70C (Kenny et al. (1990)) and bind to ssDNA. The p70 and p32 subunits of bovine RP-A are phosphorylated by CDC2-cyclin B kinase. Bovine RP-A supports the origin dependent unwinding of SV40 DNA by T antigen. Furthermore, bovine RP-A can efficiently substitute for human RP-A in SV40 DNA replication in vitro. A modified blotting technique revealed that RP-A interacts specifically and directly with the p48 subunit of DNA polymerase alpha-primase complex.

Ammonium Sulfate↗
PubMed1992

Neuromuscular blockade in aeromedical airway management.

STUDY OBJECTIVE: Induction of paralysis before intubation is controversial in the aeromedical setting. We reviewed our experience using neuromuscular blockade with nurse/paramedic aeromedical teams to determine effectiveness and outcome. MATERIALS AND METHODS: In 670 flights during a 16-month period, 119 patients required endotracheal intubation aided by muscle relaxant administration. Age ranged from two months to 83 years, with a mean of 33 years. All patients were hyperventilated with 100% oxygen before intubation. Sedation was given if presenting systolic blood pressure was greater than 100 mm Hg. A short-acting depolarizing agent was then given in a 1-mg/kg dose. Once the airway was secure, a longer-acting, nondepolarizing agent and/or sedation was given. RESULTS: Of the 119 patients, 115 (96.6%) were orally intubated. Four (3.4%) required surgical airway intervention because of injuries and conditions prohibiting oral intubation. Of 115 oral intubations, 99 (86%) were achieved on the first attempt. Eight patients (7%) were intubated on a second attempt, and another eight were intubated on a third attempt. There was no change in operator. Sixty-eight percent of patients requiring airway management were multiple trauma victims with associated head injuries. There were no laryngeal injuries, detected cardiac rhythm changes, bleeding episodes, or neurologic complications despite incomplete cervical-spine evaluation. CONCLUSION: Neuromuscular blockade can be used safely and effectively in the field by experienced nurse/paramedic teams. Although problematic intubation was not eliminated, the difficulties encountered were manageable and the overall risk/benefit ratio was acceptable.

Adolescent↗
PubMed1992

Gas2, a growth arrest-specific protein, is a component of the microfilament network system.

In this report we analyze the protein product of a growth arrest-specific gene, gas2, by means of an affinity-purified antibody raised against the protein produced in bacteria. The regulation of Gas2 biosynthesis reflects the pattern of mRNA expression (Schneider, C., R. King, and L. Philipson. 1988. Cell. 54:787-793): its relative level is tightly associated with growth arrest. Gas2 seems to be regulated also at the posttranslational level via a phosphorylation mechanism. Gas2 is well conserved during the evolution with the same apparent molecular mass (36 kD) between mouse and human. We also demonstrate that Gas2 is a component of the microfilament system. It colocalizes with actin fiber, at the cell border and also along the stress fiber, in growth-arrested NIH 3T3 cells. The pattern of distribution, detected in arrested cells, can also be observed in growing cells when they are microinjected with the purified GST-Gas2 protein. In none of the analyzed oncogene-transformed NIH 3T3 cell lines was Gas2 expression induced under serum starvation.

3T3 Cells↗
PubMed1992

Oesophageal pH-metry: should meals be standardized?

To assess the effect of a late-evening, high-fat meal on nocturnal supine gastro-oesophageal reflux, eight healthy volunteers (aged 20 to 38 years) underwent two ambulatory oesophageal pH-metry recordings, the first after a standardized light meal at 1930 h and the second after a high-fat meal including peppermint and chocolate, at 2130 h. Between 2300 and 0700 h, when subjects were supine, the median acid exposure time (percentage recording with pH less than 4) increased from 0.0% (range, 0.0-6.8%) after the standardized meal to 7.9% (0.0-17.8%) after the high-fat meal (p = 0.031). Similarly, the median number of reflux episodes increased from 0 (0 to 11) after the standardized meal to 7 (0 to 26) after the high-fat meal (p = 0.031). Reflux occurred after both meals, but, in general, persistent nocturnal reflux was observed only after the high-fat meal. Thus, the analysis of oesophageal pH recordings should consider the effects of meal composition and timing on oesophageal acid exposure.

Adult↗
PubMed1992

[Cushing syndrome in a neuroendocrine pancreatic tumor. Clinicopathologic case report].

A 59-year-old female patient with mild clinical features of a Cushing syndrome underwent surgery for a suspected hormonally active tumor of the left adrenal gland. Surprisingly, the adrenal gland was unremarkable, however, a tumor in the pancreatic tail was found. A left pancreatic resection with splenectomy resulted in curative removal of the tumor. The pathohistological examination of the tumor established the diagnosis of an ACTH-producing pancreatic carcinoid. Morphology and pathogenesis of pancreatic carcinoids which are tumors of the APUD-cell-system are discussed in detail.

ACTH Syndrome, Ectopic↗
PubMed1992

[Whose nose?].

Explore the source record for details and available documents.

Adult↗
PubMed1992

Evaluation of ground ambulance, rotor-wing, and fixed-wing aircraft services.

It is hoped that this article has offered insightful suggestions and criteria in choosing the most appropriate method to transport patients. Ground ambulances, rotor-wing, and fixed-wing aircraft each have advantages and disadvantages in particular circumstances. The advantages and disadvantages of any mode of transport must be considered to best meet the needs of the patient. In the twentieth century alone, great strides have been made in the field of emergency stabilization and transport. An efficient, well-trained ground ambulance program remains the backbone of prehospital and interhospital transport systems. Helicopters and fixed-wing transports must be integrated into the EMS system. One advantage of the helicopter and fixed-wing aircraft is rapid travel times when time is critical. As Hicks et al said, "early resuscitation and timely transfer of selected patients are critical factors in reducing morbidity and mortality." The future holds many possibilities for enhanced patient transport. Hospitals may be able to use tilt-rotor, vertical landing, fixed-wing aircraft to combine the advantages of helicopter and fixed-wing aircraft. After all, our primary goal is to get the right patient, with the right personnel, to the right place in the right amount of time.

Aircraft↗
PubMed1991

Change in the expression of a nuclear matrix-associated protein is correlated with cellular transformation.

We have identified a monoclonal antibody that recognizes a nuclear matrix-associated protein in NIH 3T3 cells. The immunofluorescence pattern consists predominantly of bright nuclear granule clusters distributed throughout the nucleoplasm, with the exclusion of nucleoli. It recognizes a protein of 190 kDa that is down-regulated to various degrees in a panel of single-oncogene-transformed NIH 3T3 cells. Its localization is similar, but not identical, to the spliceosomal speckles. p190 shows a coordinate expression during the growth cycle of nontransformed NIH 3T3 cells; it is synthesized at the highest level under growth arrest conditions. It is expressed in adult mouse brain and is also present in human IMR-90 fibroblasts.

Animals↗
PubMed1991

S-cyclophilin. New member of the cyclophilin family associated with the secretory pathway.

Cyclophilin is an abundant and ubiquitous cytosolic protein that is conserved throughout evolution from man to bacteria. It is the target of the immunosuppressive drug cyclosporin A. Cyclophilin has peptidyl-prolyl cis/trans-isomerase activity, and it accelerates protein folding in vitro, suggesting that it might be involved in the folding of cytosolic proteins. We describe a novel cyclophilin-like protein, S-cyclophilin, in the chick. Analysis of S-cyclophilin cDNA revealed the presence of a signal sequence followed by an open reading frame coding for a protein very similar to cytosolic cyclophilin, except for the presence of unique additional short amino acid segments at the N and C termini of the protein. S-Cyclophilin mRNA was abundant and present in all embryonic chick tissues tested. Cyclophilin and S-cyclophilin are coded by separate genes in the chick genome. Recombinant S-cyclophilin was expressed in insect cells by means of the baculovirus system. Pulse-chase experiments revealed that a significant fraction of newly synthesized recombinant S-cyclophilin was rapidly secreted into the culture medium. Our findings indicate that cyclophilins are associated with most if not all intra- and extracellular compartments and suggest that enzyme-assisted conformational conversions in proteins might also take place in post-endoplasmic reticulum compartments, possibly including the extracellular space.

Amino Acid Isomerases↗
PubMed1991

Histamine release induced by opioid analgesics: a comparative study using porcine mast cells.

Studies in vitro have demonstrated histamine release induced by opioid analgesics from rat peritoneal mast cells and human skin mast cells. In humans, elevated plasma histamine levels have also been found following intravenous or oral administration. This study compared the reactivity of five opioid analgesics on mast cell suspensions obtained from porcine heart, kidneys, liver and lungs. The five compounds investigated were hydromorphone, levomethadone, morphine, pethidine and oxycodone. Both morphine and hydromorphone produced little histamine release from all cell types tested. The other drugs demonstrated clear differences between the different cell populations. Thus, the cardiac cells responded most strongly to oxycodone but were the least responsive to pethidine. These differences, if confirmed in vivo, could indicate which drugs may be more suitable for patients with different underlying disease states.

Analgesics, Opioid↗