Search PubMed⌕ Search

Biomedical subjects

R Fink

Publications and source records attributed to R Fink.

At least 145 records · Page 8Linked to original sources
PubMedDate not supplied

Influence of different planes of energy supply prior to the breeding season on blood metabolites in female mink (Mustela vison).

Metabolic blood profiles were studied in a total of 30 female mink (Mustela vison) at different planes of nutrition prior to the breeding season in a control (CON; n = 10), a flushed (FLUSH; n = 10) and a negative energy balance group (NEG; n = 10). The animals were kept in metabolism cages or under normal farm conditions, respectively. The experiment, which was divided into six 1-week periods, started on 6 February and continued until 20 March. Flushing was performed by restricted feeding in periods 2 and 3 and refeeding in periods 4 and 5. The animals were weighted weekly and blood sampled at the end of periods 1, 2 and 4, 1 week after changes in the food supply of the FLUSH group. Plasma was analysed for insulin, insulin-like growth factor-1, total triiodothyronine, total thyroxine, free thyroxine, glucose and fructosamine. Generally, within the FLUSH group, animal live weights and blood metabolites were strongly influenced by energy supply, these variables remained almost constant in the CON group. In the NEG group the live weight, total triiodothyronine, total thyroxine, insulin and glucose concentrations decreased significantly. Differences in blood metabolites between the FLUSH and CON groups were non-significant, reflecting only small differences when considered over the total experimental period, thus reflecting an acute response to a varied energy supply, while the differences between the NEG group and the CON and FLUSH groups were significant, indicating a considerable chronic response in all metabolites to a constantly low energy supply.

Animal Nutritional Physiological Phenomena↗
PubMedDate not supplied

LH release in mink (Mustela vison). Pattern of the LH surge and effect of metabolic status.

The mink is a seasonal breeder with induced ovulation and delayed implantation. Reproductive processes are strongly influenced by energy supply and body condition. Items for which there is paucity or complete lack of data were the main objectives of this study: the temporal relationship between copulation and the pre-ovulatory LH surge and the influence of energy supply on LH release. A total of 30 yearling female mink with a well defined metabolic status was used. Twelve females kept in the laboratory were measured in six consecutive one-week balance periods each including the measurement of heat production by means of indirect calorimetry, and 18 females were kept under conventional farm conditions. The animals were fed so as to maintain energy balance (CON), flush fed by 2 weeks food restriction followed by 2 weeks refeeding (FLUSH), or kept in a negative energy balance (NEG). Plasma concentrations of the thyroid hormones, IGF-1 and insulin were determined weekly (n = 12), or 1 week after change in energy supply to the FLUSH group (n = 18). On the day of mating, blood samples for LH and oestradiol-17beta (E2) were taken before and immediately after mating and then 4, 8, 12, 24, 30 and 48 h thereafter. Frequent blood samplings, each lasting 60 min, were taken during the LH surge from two other females surgically fitted with venous access ports. Peak concentrations of LH were recorded on the first sampling, an average 16 min after mating. The concentrations remained elevated for 12 h, but almost decreased to basal values 24 h after mating. Plasma E2 was high before mating and peak values were attained 4 h after mating after which it decreased. Energy supply had no significant influence on LH and E2, but there was a tendency for a more sluggish LH release in NEG animals. The lack of response in FLUSH animals was explained by these animals having a lower intake of metabolisable energy than CON animals, the total intake not being significantly different from the NEG group. Plasma concentrations of thyroid hormones, IGF-1 and insulin were not significantly affected by the treatment, but in FLUSH animals the values mirrored energy supply, and in the NEG group, the values tended to decrease during the course of the experiment. It was concluded that the pre-ovulatory LH surge is an immediate response to mating, and that reproductive activity in the mink is maintained over a wide range of energy supply and body condition.

Animals↗
PubMedDate not supplied

Salt water-acclimated pink salmon fry (Oncorhynchus gorbuscha) develop stress-related visceral lesions after 10-day exposure to sublethal concentrations of the water-soluble fraction of North Slope crude oil.

Pink salmon fry. Oncorhynchus gorbuscha, after a 10-day exposure to one of two sublethal concentrations (25-54 microg x L(-1) or 178-348 microg x L(-1)) of the water-soluble fractions from Alaska North Slope crude oil, possessed morphologic and stress induced lesions in their hepatic, head kidney and gill tissues. Analysis of livers from oil-exposed fry revealed a variety of hepatocellular changes, including steatosis, nuclear pleomorphism. megalocytosis and necrosis. Epithelial proliferation of the bile ducts also occurred. An increase in the head kidney's interrenal cell nuclear diameter, a biomarker for stress responses, was correlated with hydrocarbon exposure. Gill abnormalities such as eqithelial lifting. fusion, mucous cell hyperplasia and vascular constriction were found in all test groups, but were more severe in fry given the high water soluble fraction of crude oil. The study demonstrated that sublethal exposure to the water-soluble fraction of crude oil results in multiple microscopic lesions (in several viscera) that are consistent with a pronounced response to environmental stress.

Acclimatization↗
PubMedDate not supplied

A case study in assessing an ethnically diverse community-based aging population: a multimethod approach.

Obtaining useful information to improve services for older, multi-ethnic populations requires a nontraditional approach to assessing needs that can overcome both cultural barriers and natural suspicions about research. This case study describes a multimethod needs assessment conducted in a large senior housing facility, where 58% of residents were non-English-speaking. Methods of data collection were both qualitative and quantitative. Data were gathered by focus groups, interviews, and a written survey (N = 874) on topics of need for personal care assistance, level of assistance required for instrumental activities of daily living, and mobility. Qualitative inquiry yielded information about facilities and safety, and culturally specific needs, particularly communication. The case study concludes by discussing how the research findings translated into on-site programmatic changes, and delineating the factors that contributed to the success of this approach.

Activities of Daily Living↗
PubMedDate not supplied

Containment considerations for the biotechnology industry.

The handling of hazardous organisms or chemical substances in any research and development activity must be performed in such a manner as to minimize worker exposure to these materials. The term containment is used to describe the assemblage of primary and secondary preventive measures that provide personal, experimental, and environmental protection.

Biotechnology↗
PubMedDate not supplied

Risk assessment of biological hazards in the biotechnology industry.

Almost 15 years have elapsed since the discussions of the risk of biotechnology began. The tentative principles proposed years ago, that microorganisms were to be contained through the application of proper procedures and practices, and the use of proper facilities and equipment, and that the level of containment was to be matched to the estimated risk, remain applicable and of value today.

Biotechnology↗
PubMedDate not supplied

Health promotion and disease prevention in HMOs: a survey of newly established IPAs in New York City.

Independent Practice Associations (IPAs) are the fastest growing segment of the Health Maintenance Organization (HMO) industry, but little is known about their provision of health promotion and disease prevention to subscribers. To examine the extent to which IPA policies encourage health promotion and disease prevention, we interviewed medical directors and other senior administrators of six newly developing IPA-HMOs in New York City. We also reviewed promotional literature to assess how extensively health promotion and disease prevention were marketed to the potential subscriber. Although medical protocols for preventive screening exist in most IPAs, compliance with guidelines is left largely to the individual physician's judgment for implementation. IPA respondents suggested that their physician panels are oriented toward prevention, but there is uncertain evidence in this regard, and incentive payments could discourage referrals for screening. Health education programs are sporadic. Health promotion and disease prevention do not appear to be a high priority among six newly established IPAs in New York City. We recommend several steps that would encourage IPA-HMOs to increase their health promotion activities.

Adult↗
PubMedDate not supplied

Significance of increased efforts to gain participation in screening for breast cancer.

With increasing evidence of the effectiveness of mass screening in reducing mortality from breast cancer, the Breast Cancer Screening Study of the Health Insurance Plan of Greater New York is reviewed for its impact on increased efforts to gain participation among its target population. Initial contact efforts brought a 47% response rate, and further efforts increased this to 65%. The additional contact efforts increased response rates among most demographic groups. Women requiring minimum contact efforts were appreciably more likely than the increased effort group to participate in the full set of four screenings. Among those requiring increased efforts, more than 40% had the full set of screening examinations, and about 80% had at least one screening examination in addition to the baseline. Differences in breast cancer detection rates among contact effort groups were small, and there was little difference in mortality from breast cancer. Mortality rates from other causes, however, were higher among reluctant participants and highest among women who refused screening. Efforts to increase participation in screening for breast cancer should be linked to women's concerns with other health problems and to their medical care system.

Adult↗