Search PubMed⌕ Search

Biomedical subjects

G Cole

Publications and source records attributed to G Cole.

At least 37 records · Page 2Linked to original sources
PubMed1998

Using "stages of behavioral change" constructs to measure the short-term effects of a worksite-based intervention to increase moderate physical activity.

We evaluated a three-level incentive program to promote regular, moderate physical activity among employees working in a federal agency. The objective was to assess the short-term effects of the intervention by examining the stages people go through as they attempt to make permanent changes in physical activity. Indicators of the process by which changes in physical activity take place were based on a modified version of the Transtheoretical Model of Behavior. A one-group pretest/posttest design was used to ascertain which of the stages the 1,192 participants were in both before and after the intervention. Analysis indicated that, of the 1,192 participants, 6.5% regressed one or more stages, 30.3% did not regress or progress from one stage to another, 27.7% remained in the maintenance stage, and 35.4% progressed one (21.1%) or more (14.3%) stages during the 50-day intervention. Among those who progressed, the most common change was from preparation to late preparation (20.8%) and from late preparation to action (19.4%). Findings reinforce the notion that the stages of change concept can serve as indicators of the change process which in turn, can be used as evidence of the short-term effectiveness of interventions. Findings also indicate this type of intervention holds promise for increasing physical activity among willing participants of a worksite population.

Behavior Therapy↗
PubMed1997

Spheroid body myopathy revisited.

Having reported spheroid body myopathy from Indiana (IN) inherited in an autosomal-dominant fashion several years ago, we now describe additional findings from the Oregon branch--briefly recorded earlier--and confirm earlier studies in another clinically affected IN member of this kinship demonstrating identical spheroid bodies within the myopathic muscle specimens. The spheroid bodies also contained increased amounts of desmin, alpha-B crystallin, and ubiquitin within muscle fibers. Our studies now have established that spheroid body myopathy is a member of the growing family of desminopathic neuromuscular conditions.

Adult↗
PubMed1997

Factors associated with client-reported HIV infection among clients entering methadone treatment.

To determine demographic and behavioral factors associated with client-reported HIV infection among new enrollees in methadone maintenance treatment programs (MMTPs) in Massachusetts and Connecticut, we examined ethnographic data and interview data from MMTP clients (N = 674). Clients responded to questions about behaviors in the 30 days before drug treatment. ETHNOGRAPH was used to analyze qualitative data, and logistic regression analysis was used to identify variables associated with client-reported HIV infection. Statistical significance was set at p < .05. The client-reported HIV infection rate was 20% (132/674). Odds ratios for factors associated with client-reported HIV infection were being white (0.53), increase in age (1.07), use of non-injected heroin (0.12), use of injected heroin (6.24), cocaine injection (1.78), sharing of "works" with strangers (2.15), and "safer sex" behavior (4.04). Additionally, 35% of those who did not use illicit drugs reported being seropositive. The qualitative data suggested HIV positive clients were concerned about protecting sex partners, and learning of HIV infection motivated some to stop using drugs. Although some clients engaged in low-risk behaviors, others did not, therefore the potential for HIV transmission among injection drug users (IDUs) in Connecticut and Massachusetts exists. HIV prevention and drug treatment program personnel should reinforce and build on the low-risk behaviors that are acceptable and adopted by some in this population.

Adult↗
PubMed1996

Correlative memory deficits, Abeta elevation, and amyloid plaques in transgenic mice.

Transgenic mice overexpressing the 695-amino acid isoform of human Alzheimer beta-amyloid (Abeta) precursor protein containing a Lys670 --> Asn, Met671 --> Leu mutation had normal learning and memory in spatial reference and alternation tasks at 3 months of age but showed impairment by 9 to 10 months of age. A fivefold increase in Abeta(1-40) and a 14-fold increase in Abeta(1-42/43) accompanied the appearance of these behavioral deficits. Numerous Abeta plaques that stained with Congo red dye were present in cortical and limbic structures of mice with elevated amounts of Abeta. The correlative appearance of behavioral, biochemical, and pathological abnormalities reminiscent of Alzheimer's disease in these transgenic mice suggests new opportunities for exploring the pathophysiology and neurobiology of this disease.

Aging↗
PubMed1996

Detection of Mycobacterium tuberculosis in respiratory specimens by strand displacement amplification of DNA.

A total of 294 clinical respiratory specimens, including 75 with culture-positive results, were tested for the presence of Mycobacterium tuberculosis by strand displacement amplification (SDA) of DNA. A region of the IS6110 insertion element and an internal control sequence were amplified and then detected by a chemiluminescence assay. Receiver operator-characteristic curves were used to evaluate three methods for declaring specimens positive for M. tuberculosis. By the preferred method, SDA chemiluminescence results were converted to theoretical numbers of M. tuberculosis organisms. A positive threshold (PT) value, above which 95% of the SDA results were judged to be M. tuberculosis positive (sensitivity = 95%), was found to be 2.4 M. tuberculosis organisms per SDA reaction. The analogous PT value for 95% sensitivity on smear-positive specimens was 3.6 M. tuberculosis organisms per reaction. The PT of 2.4 M. tuberculosis organisms per reaction detected 100% of culture-positive, smear-positive specimens (sensitivity = 100%), while 95% sensitivity was achieved with a PT of 15.5 M. tuberculosis organisms per reaction. Specificities, which were calculated with respect to culture- and smear-negative specimens, ranged from 96% at a PT of 15.5 M. tuberculosis organisms to 84% at a PT of 2.4 M. tuberculosis organisms per reaction. The M. tuberculosis-negative specimens were also segregated according to whether the patients received antituberculosis chemotherapy. SDA specificity ranged from 90% (PT = 2.4 M. tuberculosis organisms) to 98% (PT = 15.5 M. tuberculosis organisms) for the M. tuberculosis-negative specimens from patients who had not received chemotherapy. SDA specificity in the M. tuberculosis-negative specimens from patients who received chemotherapy was lower (85 to 94%). This study represents the first large-scale demonstration of M. tuberculosis detection in clinical sputum specimens by isothermal DNA amplification with SDA.

Bacteriological Techniques↗
PubMed1996

Interaction of organ donor families and recipients.

An exploratory descriptive study of donor families and recipients of cadaveric organs was done to determine their feelings about direct contact with each other. Direct contact was desired by 70% of donor families and 75% of recipients. Donor families wanted to see firsthand the benefit of the transplant to another person. Recipients primarily wanted to express gratitude. Both groups think they have a right to meet. Although both think these interactions should be professionally regulated and facilitated, they do not think the transplant center or the organ procurement organization is responsible for the outcome of a meeting. Donor families and recipients think the process should be gradual with prior correspondence. On the basis of our findings, we have developed a list of suggested guidelines to use when facilitating an interaction.

Adult↗
PubMed1995

In vitro activity of A-86719.1, a novel 2-pyridone antimicrobial agent.

This study evaluated the in vitro activity of A-86719.1, a novel 2-pyridone antimicrobial agent. The drug inhibited all tested members of the family Enterobacteriaceae at < or = 0.5 microgram/ml and all tested Pseudomonas aeruginosa, Burkholderia (Pseudomonas) cepacia, and Xanthomonas maltophilia strains at < or = 2 micrograms/ml. All but two strains of gram-positive bacteria were inhibited by < or = 1 microgram of the new drug per ml, including isolates highly resistant to ciprofloxacin.

Anti-Bacterial Agents↗
PubMed1995

The effects of supercooling chemicals on myocardial ultrastructure: a transmission electron microscopy case study.

Extended ischemia results in organ infarction which limits the availability of donor hearts. Hypothermic storage extends heart preservation by effectively stopping cellular metabolism, thereby preventing toxic accumulations of metabolic wastes and depletion of energy stores. However, cell swelling as a result of ion concentration changes and cell laceration due to ice crystal growth are consequences of hypothermic ischemia. Supercooling successfully preserves hearts for an extended time without associated myocardial necrosis. The efficacies of four supercooling preservative solutions, containing hypertonic glucose, polyethylene glycol, and or winter flounder antifreeze protein, are assessed using the Langendorff isolated organ perfusion apparatus and transmission electron microscopy. Polyethylene glycol seems the most effective in preventing myocardial necrosis possibly by dehydrating, minimizing cellular ice formation, protecting against cell swelling, and functioning as an antioxidant. Hypertonic glucose seems the most effective in reducing cell swelling; it may also depress solution freezing points, bind water, adjust both intra- and extracellular osmolarities, stabilize proteins, and assist in adenosine triphosphate (ATP) production. Antifreeze protein seems to bind effectively to ice and inhibit its growth; it may also reduce membrane permeabilities to Ca2+ and K+ ions.

Animals↗
PubMed1994

Autopsy findings in patients with mental handicap.

Autopsies were carried out on 60 mentally handicapped patients and the brain was examined in detail in all cases. The clinical records were studied and correlated with the pathological findings. A variety of pathological changes were found in the central nervous system, and there was a high incidence of microcephaly and gross abnormalities among the patients with epilepsy and neurological dysfunction. The incidence of Alzheimer's disease was very high among patients with Down's syndrome, but in those patients without Down's syndrome, the incidence appeared to be much the same as in the general population. The most common cause of death was respiratory disease, followed by cardiovascular disease. There was a high incidence of volvulus among the group with epilepsy. The findings are discussed, and reference made to the long-term care of the mentally handicapped. The study demonstrates the importance of the autopsy in terms of furthering knowledge in the field of mental handicap.

Adult↗
PubMed1994

In vitro activities of two glycylcyclines against gram-positive bacteria.

The glycylcyclines designated CL 329,998 and CL 331,002 are N,N-dimethylglycylamido derivatives of minocycline and 6-demethyl-6-deoxytetracycline, respectively. In vitro activities of these two antimicrobial agents were compared with those of tetracycline, minocycline, and seven other antimicrobial agents against 412 gram-positive organisms. Both new drugs were significantly more active than minocycline against methicillin-resistant Staphylococcus aureus (MICs for 90% of isolates tested, 0.25 and 0.5 microgram/ml versus 4 micrograms/ml). CL 329,998 inhibited all streptococci, lactobacilli, and Leuconostoc spp. at concentrations of < or = 0.5 microgram/ml, with CL 331,002 slightly less active against some species. All enterococci, including minocycline-resistant and multidrug-resistant isolates, were inhibited at < or = 0.5- and < or = 1.0-microgram/ml concentrations of the new drugs, respectively. Only bacteriostatic activity was evident by time-kill curves. The two glycylcyclines demonstrated activities in vitro that were superior to those of minocycline against several gram-positive bacterial species, and at relatively low concentrations, they inhibited isolates resistant to both tetracycline and minocycline.

Anti-Bacterial Agents↗
PubMed1993

A polymorphism of the human beta 2-adrenergic receptor within the fourth transmembrane domain alters ligand binding and functional properties of the receptor.

We have recently identified several naturally occurring variants of the human beta 2-adrenergic receptor (beta 2AR). One of these polymorphisms, which is relatively uncommon, is a mutation occurring in the fourth transmembrane spanning domain, with Ile substituted for Thr at amino acid 164 within the proposed ligand binding pocket. This mutation is adjacent to Ser165 which has been predicted to interact with the beta-carbon hydroxyl group of adrenergic ligands. To determine the functional significance of this variant, we constructed by site-directed techniques a mutated beta 2AR (Ile164) with this substitution and expressed it in CHW-1102 cells. In the presence of guanine nucleotide, Ile164 displayed a lower binding affinity for epinephrine as compared with the wild-type beta 2AR (Ki = 1450 +/- 79 versus 368 +/- 39 nM; p < 0.001). A similarly decreased affinity was found with the catecholamines isoproterenol and norepinephrine, but not with dobutamine or dopamine which lack hydroxyl groups on their beta-carbons. In addition, antagonists without aromatic ring polar substituents displayed a decreased affinity for the mutated receptor. In agonist competition experiments conducted in the absence of guanine nucleotide, Ile164 failed to exhibit detectable high affinity binding, suggesting an impairment in the formation of the agonist-receptor-Gs complex. Consistent with this finding, functional coupling to Gs as determined in adenylyl cyclase assays was significantly (approximately 50%) depressed with Ile164 under both basal and agonist-stimulated conditions. beta 2AR sequestration, which is also triggered by agonist binding, was also found to be approximately 65% reduced in the Ile164 polymorphism. This study represents the first characterization of a naturally occurring mutation of a human adrenergic receptor. Our findings generally support the hypothesized role of this region of the receptor for ligand binding and receptor activation, as well as for establishing critical interactions for overall receptor conformation.

Adenylyl Cyclases↗
PubMed1993

The distribution of amyloid plaques in the cerebellum and brain stem in Down's syndrome and Alzheimer's disease: a light microscopical analysis.

The distribution and severity of the neuropathological changes in 57 cases of Alzheimer's disease, and 11 patients with Down's syndrome were investigated with reference to the cerebellum. A modified silver stain and a monoclonal antibody raised against amyloid beta-protein were used to identify amyloid plaques. The highest incidence of amyloid plaques in the cerebellum (93%) was found in the group of patients who developed dementia before 65 years of age. This figure dropped to 56% in those patients with dementia beginning after 75 years. In 37 of these cases the distribution of the pathological changes of the disease were also examined in the brain stem. The severity of the pathological changes in the cerebellum corresponded to the involvement of the brain stem nuclei with connections to the cerebellar cortex. The possibility that the disease process spreads to the cerebellum by involving the fibres from the brain stem is discussed with reference to previous anatomical and neurochemical studies.

Adult↗
PubMed1993

Serotonin involvement in the antitumour and host effects of flavone-8-acetic acid and 5,6-dimethylxanthenone-4-acetic acid.

The relationship of serotonin (5-HT) receptors to the action of the experimental antitumour drugs flavone-8-acetic acid (FAA) and 5,6-dimethylxanthenone-4-acetic acid (5,6-MeXAA) was studied. Both FAA and 5,6-MeXAA are known to induce the synthesis of tumour necrosis factor-alpha (TNF) and to stimulate nitric oxide synthesis in vivo, as measured by elevation of plasma nitrate. Serotonin potentiated the effect of a subtherapeutic dose of 5,6-MeXAA (20 mg/kg) as measured both by plasma nitrate increase and by growth delay of s.c. implanted colon 38 tumours. On the other hand, administration of the serotonin 5-hydroxytryptamine-2 (5-HT2) antagonist cyproheptadine (20 mg/kg) inhibited both the plasma nitrate response and, to a lesser extent, the induction of tumour haemorrhagic necrosis by 5,6-MeXAA, FAA and TNF. Reduction of circulating plasma serotonin by pre-treatment with p-chlorophenylalanine and reserpine reduced the plasma nitrate response, but not the tumour necrosis response, to 5,6-MeXAA (30 mg/kg). It is suggested that serotonin is necessary for the induction of nitric oxide synthases and acts, either directly or indirectly, in concert with TNF. Serotonin agonists may have utility in increasing nitric oxide synthesis in response to TNF or to agents that induce TNF as part of their antitumour action.

Animals↗
PubMed1993

Malignant osteoblastoma of the skull.

A bone tumour of intermediate grade malignancy in the skull is described. These tumours are extremely rare and share several histological features with the benign osteoblastomas and low grade osteosarcomas. They may be associated with local invasion and pulmonary metastases. Treatment of this tumour in the skull poses several problems in view of its proximity to the cerebral cortex.

Adult↗
PubMed1993

The effects of prenatal care utilization and maternal risk factors on pregnancy outcome between Mexican Americans and non-Hispanic whites.

This study evaluates the effects of prenatal care classification and levels of maternal risk status on pregnancy outcomes in Mexican Americans and non-Hispanic whites in Arizona. All live birth certificates from 1986 and 1987 were reviewed yielding a total population of 101,206 (26,827 Mexican Americans). The adequacy of prenatal care was evaluated based on an index that includes six prenatal care groups. Two levels of maternal risk status (low and high) were defined based on a series of maternal risk factors. Overall, Mexican Americans had a greater proportion of maternal risk factors and a greater proportion of mothers with inadequate or no prenatal care compared with non-Hispanic whites. Prematurity and macrosomia were more prevalent than low birthweight in Mexican Americans. Low-risk status and adequate prenatal care regardless of ethnicity were found to be associated with a lower prevalence of low birthweight and preterm delivery. Whites, however, had a greater variation in the prevalence of low birthweight associated with changes in prenatal care utilization and maternal risk status compared with Mexican Americans. Finally, logistic regression analysis showed an independent effect of prenatal care, maternal risk status, maternal age, and maternal birthplace in predicting the overall low birthweight rate in Mexican Americans. The implications of these results are discussed relative to the usefulness of prenatal care as a health-care intervention in Mexican Americans.

Female↗