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W Nash

Publications and source records attributed to W Nash.

9 recordsLinked to original sources
PubMed2002

Dynamic light scattering investigation of sodium caseinate and xanthan mixtures.

Aqueous solutions of sodium caseinate and xanthan at pH 7 and containing 0.1 M NaCl, and their mixtures were investigated using dynamic light scattering. Sodium caseinate solutions showed a bimodal distribution of relaxation rates; with the aggregate peak distribution predominating. Xanthan solutions showed a single distribution at low concentrations (< or =0.06 wt.%) and a bimodal distribution at higher concentrations. The sodium caseinate-xanthan mixture modes were independent of the total biopolymer concentration, and behaved as a superposition of sodium caseinate solution alone and xanthan solution alone. This indicates that there is no interaction between xanthan and sodium caseinate in the range of concentrations considered in this study.

Caseins↗
PubMed2002

Insulin, unlike food intake, does not suppress ghrelin in human subjects.

UNLABELLED: Food intake suppresses plasma levels of the gastric peptide ghrelin in humans. We hypothesize that the food intake- suppression of ghrelin could be secondary to the plasma glucose and insulin changes after a meal. The aim of this study was to compare the effect of the administration of a combined pulse of glucose and insulin to the effect of one meal on plasma ghrelin in human subjects. A secondary aim was to study the effect of an oral glucose load on ghrelin levels. METHODS: Experiment 1 (n = 10) studied plasma glucose, insulin, leptin and ghrelin for 6 hours after a 790 kcal liquid meal. In Experiment 2 (n = 7), a subcutaneous pulse of insulin (Humalog 0.03U/kg) and an I.V. infusion of glucose were administered in order to mimic the plasma changes of glucose and insulin after a meal, and plasma ghrelin levels were monitored for 9 h. The OGTT data was used to study the effect of oral glucose on ghrelin. RESULTS: A mixed liquid meal decreased basal serum ghrelin by 26% at 40 minutes (p = 0.009). A 75 gr oral glucose load suppresses ghrelin by 28% at 30 minutes. Contrary to the meal effect, the parenteral administration of insulin and glucose did not suppress serum ghrelin. CONCLUSION: Unlike food intake, the administration of insulin and glucose does not suppress ghrelin levels. These data suggest that the suppressive effect of food intake or oral glucose on serum ghrelin is unlikely mediated by the changes of plasma insulin and glucose observed after the ingestion.

Administration, Oral↗
PubMed1999

Vertebrate slit, a secreted ligand for the transmembrane protein roundabout, is a repellent for olfactory bulb axons.

The olfactory bulb plays a central role in olfactory information processing through its connections with both peripheral and cortical structures. Axons projecting from the olfactory bulb to the telencephalon are guided by a repulsive activity in the septum. The molecular nature of the repellent is not known. We report here the isolation of vertebrate homologs of the Drosophila slit gene and show that Slit protein binds to the transmembrane protein Roundabout (Robo). Slit is expressed in the septum whereas Robo is expressed in the olfactory bulb. Functionally, Slit acts as a chemorepellent for olfactory bulb axons. These results establish a ligand-receptor relationship between two molecules important for neural development, suggest a role for Slit in olfactory bulb axon guidance, and reveal the existence of a new family of axon guidance molecules.

Animals↗
PubMed1991

The initial clinical experience with an implantable cardioverter defibrillator/antitachycardia pacemaker.

Guardian antitachycardia pacing (ATP) 4210 is a third generation, multi-programmable cardioverter defibrillator undergoing Phase I clinical trials. The tiered response includes ATP, low energy cardioversion or defibrillation, and bradycardia support. Extensive telemetry is available, including an episode log and details of all episode events. Five patients underwent the implantation of Guardian ATP 4210 as part of a Phase I trial at the University of Louisville. Two of the five patients had multiple VT episodes that were reverted successfully using ATP pacing (slow VT) and defibrillation (fast VT) and VF episodes, which resulted in defibrillation therapy over a follow-up period of 6 to 8 months. Four of the five patients required bradycardia support for bradyarrhythmias unassociated with ATP therapy or defibrillation and one patient required bradycardia support postdefibrillation therapy. The device design is microprocessor based and requires continuous interrogation of the microprocessor memory and checks of the validity of programmed parameters to continue its operation. When the safety check fails, the device is designed to shut down its antitachycardia and defibrillator functions. This design feature has a potential for leaving the patient unprotected if the device shuts down. Modification of this feature is required to ensure the device's long-term safety.

Aged↗
PubMed1986

Conserved chromosomal positions of dual domains of the ets protooncogene in cats, mice, and humans.

The mammalian protooncogene homologue of the avian v-ets sequence from the E26 retrovirus consists of two sequentially distinct domains located on different chromosomes. Using somatic cell hybrid panels, we have mapped the mammalian homologue of the 5' v-ets-domain to chromosome 11 (ETS1) in man, to chromosome 9 (Ets-1) in mouse, and to chromosome D1 (ETS1) in the domestic cat. The mammalian homologue of the 3' v-ets domain was similarly mapped to human chromosome 21 (ETS2), to mouse chromosome 16 (Ets-2), and to feline chromosome C2 (ETS2). Both protooncogenes fell in syntenic groups of homologous linked loci that were conserved among the three species. The occurrence of two distinct functional protooncogenes and their conservation of linkage positions in the three mammalian orders indicate that these two genes have been separate since before the evolutionary divergence of mammals.

Animals↗
PubMedDate not supplied

Isolation and characterization of a novel human bladder cancer cell line: BK10.

Molecular studies of bladder carcinomas have aided in determining causative genetic events and the prognosis of cancers endowed with certain abnormalities. In vitro bladder cancer characterization of key cytogenetic alterations is useful for study of molecular changes that may promote oncogenic events. In our laboratory, a novel human bladder cancer cell line, BK10, has been established in vitro and passaged for more than 20 mo. This new bladder cancer cell line (BK10) was derived from bladder tissue containing grade III-IV/IV transitional cell carcinoma. Bladder cancer tissue was obtained at the time of radical cystoprostatectomy extirpation. Cell cultures derived from this surgical sample exhibited an epithelial morphology and expressed epithelial cytokeratins. Immunostains of BK10 were negative for prostate specific antigen (PSA), fibronectin, smooth muscle actin alpha, and desmin. Karyotypic analysis revealed an aneuploid chromosomal content <4n> with many numerical and structural abnormalities previously linked to bladder oncogenesis. Translocations occurred in chromosomes 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 13, 14, 15, 16, 17, 19, 20, 21, 22, X and Y. G-banding analysis revealed rearrangements involving chromosomes 9q and 17p, and the location of the ab11 oncogene and the p53 gene, respectively. The availability of this bladder cancer cell line will provide a useful tool for the further study of bladder carcinoma oncogenesis and gene therapy.

Aged↗