PubMed Health⌕ Search

Biomedical subjects

G D Martin

Publications and source records attributed to G D Martin.

8 recordsLinked to original sources
PubMed2006

Recovery of an estuary in the southwest coast of India from tsunami impacts.

Water quality in the Cochin Estuary, southwest coast of India during the tsunami attack was assessed and compared with the pre and post tsunami characteristics. From the results obtained, it is evident that a drastic change in hydrography has been inflicted by the energy transferred through the tsunami, which disturbed the entire estuarine embayment. However, the post tsunami water quality showed normal levels indicating that the region has recovered from the tsunami impacts.

Disasters↗
PubMed1995

Biological and genetic characterization of TnphoA mutants of Salmonella typhimurium TML in the context of gastroenteritis.

TnphoA transposon insertion mutants of phoN-negative derivatives of Salmonella typhimurium TML (of human gastroenteritic origin) were selected by growing mutagenized recipient bacteria under a variety of growth conditions. Ninety-seven individual mutants, which expressed alkaline phosphatase, were collected and tested for their ability to invade HEp-2 cells. Seven smooth mutants had a reduced ability to invade HEp-2 cells, and three smooth mutants were consistently more invasive than their corresponding parental strains. One rough mutant was of similar invasiveness and two were of reduced invasiveness when compared with that of parental strains. The seven smooth hypoinvasive mutants, the three smooth hyperinvasive mutants, and the three rough mutant strains were tested for their abilities to invade ileal enterocytes by the rabbit ileal invasion assay described previously (3). All smooth mutants exhibited parental levels of invasiveness. The rough mutants were hypoinvasive in the rabbit ileal invasion assay. The HEp-2 system is therefore not a good predictor of behavior in gut tissue in this model. DNA sequences flanking the transposon were determined for five mutants which were hypoinvasive in the HEp-2 cell assay. The mutations were found to be insertions in two previously identified invasion genes, invG and invH, and in a gene not normally associated with invasion, pagC. These observations lead one to be cautious in the interpretation of the biological significance of data obtained from invasion of tissue culture monolayers when extrapolated to gut tissue.

Alkaline Phosphatase↗
PubMed1990

Prospective analysis of rural interhospital transfer of injured patients to a referral trauma center.

A 1-year prospective review of 78 multiply injured patients initially treated at local community hospitals and subsequently transported more than 25 miles to a referral trauma center was completed. Injury mechanisms were blunt in 74 (95%) patients and penetrating in four. Patient ages ranged from 6 to 88 years (mean, 33 years). Trauma Scores ranged from 6 to 16 (mean, 13.9) and Injury Severity Scores ranged from 4 to 54 (mean, 21.5). The quality of care during initial stabilization and transport was evaluated by ATLS guidelines for airway management, treatment of shock, spine and fracture immobilization, neurologic evaluation, secondary assessment, and chart documentation. Most frequent departures from these standards involved failure to place a nasogastric tube before transport (72%), failure to document neurologic status (47%), inadequate cervical spine immobilization (32%), inadequate intravenous access (29%), inadequate oxygen delivery (28%), and incomplete or absent records (22%). Life-threatening deficiencies were identified in four (5%) patients and serious deficiencies in 62 (80%). This study demonstrates the need for further education of rural physicians about priorities in trauma management. Increased emphasis on stabilization and transport should be added to ATLS training courses. Established transport protocols between institutions would enhance the quality of care and engender improved interhospital communication. The implementation of trauma systems designed specifically for rural areas must be supported.

Adolescent↗
PubMed1976

Binding of polycyclic aromatic hydrocarbons to transcriptionally active nuclear subfractions of AKR mouse embryo cells.

The objective of this study was to examine the binding of carcinogenic polycyclic aromatic hydrocarbons in well-characterized nuclear subfractions from transformable cells in culture. A cloned line of AKR mouse embryo cells was exposed to culture medium containing [3H]-3-methyl-cholanthrene (MC) (0.4 mug/ml) 670 Ci/mole). Cellular uptake and nuclear binding were determined after 4 hr of exposure. The addition of unlabeled MC up to 10 mug/ml did not cause reduction of [3H]MC cellular uptake or nuclear binding. From 2 to 5% of the total cellular MC was localized in the nuclei. All nuclear subfractions obtained from mechanically sheared nuclei and separated on sucrose gradients showed some MC binding; however, a high-affinity, high-specific-activity binding of MC was associated only with the slower-sedimenting component shown to represent that fraction of nuclear chromatin that is transcriptionally active. Conditions that caused the precipitation of this chromatin also resulted in the precipitation of the radioactive compound, thus suggesting that the MC was physically bound to the chromatin. Unlabeled MC (10 mug/ml) saturated this high-affinity MC binding to the transcripitionally active chromatin but did not saturate the binding to the other nuclear fractions. The binding of another potent carcinogen, [3H]-1,2,5,6-dibenzanthracene, and the "weak" carcinogen, [3H]-1,2,3,4-dibenzanthracene (3,4-DBA), to whole nuclei and nuclear subfractions was also determined. The concentration, specific activity, and time of treatment were identical with those used for MC. The level of binding of [3H]-1,2,5,6-dibenzanthracene was approximately 3-fold greater in whole nuclei on a per mass DNA basis than in those of either the MC or the 3,4-DBA. The binding of MC and 3,4-DBA to whole nuclei was approximately equal. As with MC, the [3H]-1,2,5,6-dibenzanthracene demonstrated a peak of high specific activity binding to the slower-sedimenting fraction of chromatin while the 3,4-DBA displayed considerably less binding to this fraction.

Benz(a)Anthracenes↗