Biomedical subjects

C L Hunt

Publications and source records attributed to C L Hunt.

8 recordsLinked to original sources

PubMed2006

Sp1 and NFkappaB pathways are regulated in brain in response to acute and chronic ethanol.

DNA microarray analysis was used to identify candidate ethanol-regulated genes, as a first step towards exploring how transcriptional changes might lead to ethanol-induced changes in behaviour. Mice were treated with a single acute intraperitoneal ethanol dose and DNA microarray analysis performed on midbrain 2 h posttreatment. We predicted that if ethanol-regulated genes contribute towards behaviour, then constitutive variation in brain expression levels may also contribute to strain-specific differences in ethanol-related behaviour of inbred mouse strains. On the basis of this assumption, we interrogated the BXD inbred strain phenotype database and the U74Av2 MAS5 brain expression database using the WebQTL tool (http://www.genenetwork.org/) and correlated ethanol-related behaviours to expression levels. Constitutive expression levels of 70/90 candidate genes, identified from the DNA microarray analysis, varied significantly between inbred strains and correlated significantly with strain-specific differences in ethanol-related behaviours. These genes were then mapped onto biochemical pathways using Stratagene's PathwayAssist software. This analysis identified the transcription factor Sp1 and NFkappaB pathways in the acute response to ethanol. Ethanol regulation of Sp1 transcription was conserved between humans and mouse. As predicted, downstream targets of Sp1 were also ethanol regulated. NFkappaBia, an important regulator of NFkappaB function and Rela, an NFkappaB-binding partner, were both regulated by ethanol. Expression of both Sp1 and NFkappaBialpha were also downregulated following chronic ethanol treatment. As Sp1 and NFkappaB are implicated in plasticity and behaviour, our data suggest a role for these transcription factors in the long-term behavioural adaptations to ethanol.

Adaptation, Physiological↗

PubMed2000

Prevalence and strain differentiation of Giardia intestinalis in calves in the Manawatu and Waikato regions of North Island, New Zealand.

Giardia intestinalis has been reported in newborn calves world-wide; however, information on the extent of G. intestinalis in New Zealand calves has to date been very limited. The current study attempted to establish the prevalence rate of G. intestinalis in calves up to 8 weeks old in New Zealand. More than 700 calf fecal specimens were collected during the spring calving seasons of 1998 and 1999 from two regions in North Island, New Zealand (Manawatu and Waikato) and tested for the presence of G. intestinalis. In addition to determining the presence of G. intestinalis in newborn calves, sequence analysis was performed using specific amplification primers developed to target a section of the ribosomal DNA (rDNA). This locus is considered to be rapidly evolving, and therefore, suitable for use in the elucidation of phylogenetic relationships between G. intestinalis isolates. Sequencing was performed using G. intestinalis DNA extracted from cysts collected directly from the calf fecal matter. There was no culturing of the G. intestinalis isolates either in vivo or in vitro. Over 40% of all collected calf fecal specimens contained G. intestinalis cysts and rDNA sequence analysis revealed two different sequences among calf isolates. These sequence differences were not found to correspond to a particular season, geographical region or farming practice. Preliminary phylogenetic analysis suggests that these two rDNA sequence types are indicative of calf hosts.

Animals↗

PubMed1993

Introduction and expression of the bacterial genes cysE and cysK in eukaryotic cells.

The coding sequences of the cysE and cysK genes from Escherichia coli, which encode the enzymes of the cysteine biosynthetic pathway, namely, serine acetyltransferase (EC 2.3.1.30) and O-acetylserine sulfhydrylase (or cysteine synthase [EC 4.2.99.8]), were modified for expression in eukaryotic cells and introduced into murine L cells. A number of fusion genes comprising the cysE or cysK coding sequences joined to the promoter of the ovine metallothionein-Ia (MT-Ia) gene and various portions of the ovine growth hormone (GH) gene were prepared. Significant differences in the level of transcription were observed, depending on the amount and arrangement of the GH gene sequences used, the highest levels being obtained with the constructs MTCE10 and MTCK7, which contained only the GH 3' untranslated gene sequences. These two constructs were fused to produce the gene MTCEK1. In this single DNA sequence, each bacterial gene is under independent MT-Ia promoter control. Expression of the cysK sequence in this construct (MT-Ia promoter-cysE-3' GH sequence-MT-Ia promoter-cysK-3' GH sequence) was elevated compared with expression of the cysK gene in MTCK7. However, expression of the cysE sequence in MTCEK1 was only 40% of that of the cysE gene cloned into MTCE10. The double-promoter configuration, which enhances the expression of the second gene in MTCEK1, is proposed as a model for the modification of bacterial genes in general.

Acetyltransferases↗

PubMed1992

Catholicism and the Philippine population problem.

"The Philippines has two characteristics which differentiate if from other countries in Southeast Asia. It is the only predominantly Christian country in the region and it has one of the highest rates of population growth. Non-Catholic Christians make up only about 9 per cent of the population compared with around 82 per cent for Roman Catholics. Given the Catholic Church objections to both contraception and abortion, it is not illogical to hypothesize a relation between the religious composition of the population and its rate of population growth."

Abortion, Induced↗

PubMed1990

The potential of transgenic animals for improved agricultural productivity.

The techniques involved in the transfer of foreign DNA to domestic animals have advanced to the stage where transgenic animals that express foreign genes can be reliably produced, albeit still at low efficiency. This paper reviews the current status of some of the more important areas in agriculture where this technology is being applied. Numerous attempts have been made to modify the growth performance characteristics of domestic animals by the introduction of metallothionein/growth hormone fusion genes. A summary of our work with transgenic sheep is presented. The results demonstrate that the unregulated production of growth hormone in transgenic sheep reduces carcass fat, elevates metabolic rate and heat production, causes skeletal abnormalities and impairs survival. The introduction of new metabolic pathways to domestic animals offers an attractive approach to improved animal productivity. This paper summarises recent results of research directed towards the introduction of a cysteine biosynthetic pathway and the glyoxylate cycle to transgenic sheep. So far, the genes encoding the enzymes have been isolated and expressed both in cells in culture and in transgenic mice. The results of work currently in progress demonstrate that some modification of the fusion genes is required to enhance their expression in transgenic animals.

Agriculture↗

PubMed1987

Lambda transducing phage and clones carrying genes of the cysJIHDC gene cluster of Escherichia coli K12.

DNA from each of two specialized transducing lambda phage, lambda dcysJIHD and lambda cysJ, has been analysed by heteroduplex mapping. The segment of the Escherichia coli chromosome carried by lambda dcysJIHD was shown to be large, approximately 18 kb in length, and to replace a large length of lambda DNA, approximately 11 kb, which includes the genes for integration and recombination. Thus lambda dcysJIHD is a bio-type transducing phage. lambda cysJ was shown to have lost very little lambda DNA and to carry about 8 kb of bacterial DNA. Sites for several restriction endonucleases were mapped in the DNA from each phage and cloning experiments located some of the genes of the cluster in relation to the restriction map. Cysteine regulation of the cloned cysJ and cysD genes was shown as well as cysteine regulation of beta-galactosidase in some constructs. The direction of transcription of the cysD gene was established, and from physical evidence the size of the 'silent section' between the cysH and cysD genes was estimated to be at least 11 kb.

Bacteriophage lambda↗

PubMed1982

Philippine nurses and the brain drain.

The Philippines has been one of the greatest exporters of professional personnel to the United States, and nurses outnumber any other category. Although some problems have been reported, their experience in the United States has been generally good. A comparison of samples of Filipino nurses who never left the Philippines with those who had either remained for a long time in the United States or who had remained to the U.S. after a short period found little difference in socioeconomic background. Nurses remaining for long periods in the United States did receive lower scores on scales designed to test anchorage and perceived relative opportunities in the Philippines. The supply of Philippine nurses is growing and migration will continue at a high level if U.S. immigration policies permit.

Attitude of Health Personnel↗

PubMed1977

A system for labeling and control of toxic materials in a large research facility.

For large industrial and research operations, maintaining reasonable control of all toxic materials used in their operations can be a formidable task. A system utilizing cards has been developed which serves a dual purpose - informing the user regarding hazards of a particular material and also facilitating appropriate workplace surveillance during its use. Selected data is printed on the card. The card contains a label which the user detaches and affixes to the container. This label classifies the material according to flammability, toxicity, reactivity and special properties on a 0 through 4 hazard rating system.

Computers↗