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Biomedical subjects

J Miller

Publications and source records attributed to J Miller.

At least 1,333 records · Page 74Linked to original sources

Politics and care: a study of Czech Americans within Leininger's theory of culture care diversity and universality.

The domain of inquiry for this study was the influence of the American political environmental context on professional and generic care patterns, expressions, and meanings of Czech American immigrants. The purpose of the research was to document, describe, interpret, and analyze the diversities and universalities of professional and generic care for this cultural group, to provide culturally congruent care to Czech Americans, and to explicate the role of politics as an influence on care patterns, health, and well being. The researcher's former transcultural ethnonursing study in Prague, Czechoslovakia in 1991 served as a stimulus for this in-depth study on politics and care. Twelve key and twenty general informants were interviewed. Five major themes were identified. The researcher discovered that the capitalist economic market structure of the United States influenced informant lifeways in all dimensions of Leininger's Theory of Culture Care Diversity and Universality, as depicted in the Sunrise Model. Specific care patterns discovered included care as choice, care as responsibility, and care as helping each other. Findings related to professional and generic care supported researcher predictions that generic culture care patterns would be important to immigrants. Provisions for culturally congruent nursing care were articulated based on research findings.

Cultural Diversity↗

Dynamics of local-anesthetic compounds in regional anesthesia.

The clinical effectiveness and safety of compounded mixtures of lidocaine + bupivacaine and chloroprocaine + bupivacaine for either epidural or brachial-plexus block was studied in 48 adult patients. Of the several alternatives, chloroprocaine + bupivacaine with epinephrine was found the best choice for patients with typical plasma cholinesterase.

Adolescent↗

A modified "soft surface specimen technique" for examination of the inner ear.

A new surface preparation method was devised for assessing intracochlear vessels and sensorineurepithelium. The method is a combination of the conventional osmic acid stained surface preparation method and a surface preparation technique with injection of Prussian blue and decalcification of the cochlea. Such a combination preserves most advantages of each and eliminates many of the disadvantages. To preserve the delicate sensory and nervous structures we examined variations of the preparation, paying particular attention to fixation, staining, and decalcification procedures and solutions. Varying the preparation had a less marked effect on external wall structures than on the basilar membrane; the primary changes consisted of variation in staining contrast. The method proved useful for demonstrating the normal anatomy and pathological changes in cochlear vasculature and in sensorineural and supporting structures of the labyrinth in light and phase contrast microscopy at moderate magnifications.

Animals↗

Cochlear vascular and electrophysiological effects in the guinea pig to 4 kHz pure tones of different durations and intensities.

Round window cochlear microphonic recordings from 33 guinea pigs were obtained prior to and following exposure to a 4 kHz pure tone at levels ranging from 124 dB to 140 dB for 5 to 80 minutes. When electro-physiological evaluation was complete, the animals were killed and tje cochlear tissues prepared using a soft-surface preparation technique. Experimental and control animals were mixed and randomly assessed without prior knowledge of the groups to which the specimens belonged. Histopathological observations were quantified and computer analysed. Statistical analyses suggest that noise exposure results in an overall decrease in blood flow to the cochlea with slight intracochlear increases in flow, perhaps compensatory in nature, to locations corresponding to the 4 kHz exposed region. Results implied that the initial localized hair cell damage known to occur as a result of overexposure to a discrete pure tone is not caused by a decreased blood flow. Relationships between electro-physiological and vascular changes and noise 'dose' are discussed.

Acoustic Stimulation↗

Immediate noise effects on cochlear vasculature in the guinea pig.

Nine guinea pigs were exposed to a 4 kHz narrow band noise at 120 dB for 30 minutes. The animals were killed immediately following exposure and the cochlear tissues prepared using a soft-surface preparation technique. Experimental and control animals were mixed and randomly assessed without prior knowledge of the groups of which the specimens belonged. The results were analysed by computer. Statistically significant differences in the vasculature between noise-exposed and control animals of a general nature included: more changes in spiral lamina than external wall vessels, more changes in vessels facing perilymph than endolymph, and more changes apically than basally. Results indicate slight intracochlear compensations in blood flow, that could potentially maintain a more constant circulation in regions of the cochlea corresponding to the 4 kHz narrow band exposure noise. Methodological aspects of our inner ear vascular technique as well as some hypothetical explanations regarding the observed changes in the blood supply are discussed.

Animals↗

The recovery of vascular changes following brief noise exposure.

Histological measures of cochlear vasculature and blood flow were examined in 20 guinea pigs. Sixteen were exposed to octave band noise at 120 dB SPL for 30 min and then permitted to survive after the exposure for 6 h, 18 h, 48 h, or 4 weeks (N = 4 in each group). Control animals were exposed to the laboratory and apparatus but not to the noise and then sacrificed after 48 h (N = 2) or 4 weeks (N = 2). Statistically significant results indicate that the noise exposure resulted in reduced RBCs in the cochlea for animals permitted to survive 6 to 18 h after the noise exposure. These changes, however, were no longer apparent in animals which were permitted to survive 48 h or 4 weeks after the noise exposure. The vascular sequelae of 30 min exposure to 120 dB octave band noise appear to recover within a few days of the exposure.

Animals↗

Histological measures of cochlear blood flow. A validation study.

Cochlear blood flow in guinea pigs was assessed using histological assessment of various red blood cell and vessel lumen parameters. Cochlear blood flow was either enhanced by administration of carbogen or inhibited by induced positive airway pressure. The resulting enhancement or reduction of blood flow in the cochlea was verified by laser Doppler velocimetry. The results generally indicate that the two measures of cochlear blood flow agree. This agreement was especially apparent when histological parameters of the vessel lumen were considered and when external wall vessels were evaluated.

Animals↗

Protection of cells from complement-mediated attack: CD59 receptor clustering for the entry of macromolecules into hematopoietic cells.

CD59 is a glycosylphosphatidylinositol anchored protein (GPI-protein) that is expressed on surface membranes to protect host cells from complement-mediated attack. CD59 may also serve as a receptor for the endocytosis of macromolecules into nucleated cells. Here we investigate the effects of primary clustering of CD59 with anti-CD59 monoclonal antibody and the secondary clustering of biotinylated anti-CD59 with avidin on red blood cells and erythroleukemic K562 cells. On red blood cells, CD59-targeted antibodies remained evenly distributed on the external membranes. In contrast, clustering, capping and endocytosis of the CD59-targeted complexes was detected on K562 cells. Secondary clustering appeared more efficient and resulted in endosomal localization of the fluorescently labeled complexes within 2 hours. The endocytosis of CD59-bound complexes did not affect K562 cell viability or growth and the surface level of CD59 was constant during the process. These result suggest clustering and subsequent endocytosis of CD59 may enable the entry of macromolecules to the endosomal compartments of hematopoietic cells.

CD59 Antigens↗

Evaluation of the effectiveness of adolescent drug abuse treatment, assessment of risks for relapse, and promising approaches for relapse prevention.

A review of controlled evaluations of adolescent and other drug abuse treatment programs concludes that some treatment is better than no treatment, that few comparisons of treatment method have consistently demonstrated the superiority of one method over another, that posttreatment relapse rates are high, and that more controlled studies of adolescent treatment which allow evaluation of the elements of treatment are needed. In the absence of the clear superiority of specific treatment techniques, it is suggested that examination of factors related to relapse can provide an empirical base for identifying effective treatment approaches. Pretreatment, during-treatment, and posttreatment factors related to relapse are reviewed from existing studies of adolescent treatment. Program components are suggested which have been associated with or hold promise for reducing factors associated with higher relapse rates and increasing factors associated with lower relapse rates.

Adolescent↗

Dead crow densities and human cases of West Nile virus, New York State, 2000.

In 2000, Staten Island, New York, reported 10 human West Nile virus cases and high densities of dead crows. Surrounding counties with <2 human cases had moderate dead crow densities, and upstate counties with no human cases had low dead crow densities. Monitoring such densities may be helpful because this factor may be determined without the delays associated with specimen collection and testing.

Animals↗

Widespread West Nile virus activity, eastern United States, 2000.

In 1999, the U.S. West Nile (WN) virus epidemic was preceded by widespread reports of avian deaths. In 2000, ArboNET, a cooperative WN virus surveillance system, was implemented to monitor the sentinel epizootic that precedes human infection. This report summarizes 2000 surveillance data, documents widespread virus activity in 2000, and demonstrates the utility of monitoring virus activity in animals to identify human risk for infection.

Animals↗