Journal of investigative medicine : the official publication of the American Federation for Clinical Research
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Comparative Study
NADH-methemoglobin reductase (cytochrome b5 reductase) levels in two groups of American blacks and whites.
Sickle cell trait, glucose-6-phosphate dehydrogenase (G6PD) deficiency and alpha-thalassemia trait are common genetic abnormalities among the American Black population. Under oxidative stress, the presence of any of these conditions would predispose the hemoglobin (Hb) to oxidation resulting in accelerated methemoglobin (metHb) formation. It was hypothesized that red cells phenotypic for these genetic variants should have more or different levels of metHb reductase (cytochrome b5 reductase) activity. ⋯ It is concluded that American Blacks have significantly different metHb reductase activity. The different metHb reductase activity in Blacks seems to be unrelated to the presence of G6PD deficiency, sickle cell trait, or alpha-thalassemia and it may be the result of genetic polymorphism. However, our study samples do not exactly represent the cross-sections of the Black and White populations. In addition, all patients were male in this study. Therefore, this study should be confirmed using larger and more population-representative samples. The clinical significance of this problem is not clear at this time.
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The systemic inflammatory response syndrome (SIRS) is a marked, generalized response to a variety of injuries, if infection is implicated, the term "sepsis" is used. Systemic inflammatory response syndrome/sepsis, which is initiated by proinflammatory cytokines, has been found to be associated with increased serum levels of the prohormone of calcitonin, procalcitonin (ProCT) and its aminoterminus peptide (nProCT). The serum levels of ProCT and nProCT are very useful markers for SIRS/sepsis, and may be used to follow the course, the response to therapy, and/or the prognosis. We studied the serum levels and distribution of ProCT and its component peptides in normal persons for comparison with similar immunochemical and separatory studies in patients with neuroendocrine cancer and with SIRS/sepsis of various etiologies. ⋯ These studies indicate that ProCT and its component peptides circulate in normal persons. The serum of patients with SIRS/sepsis contains greatly increased levels of ProCT, nProCT and often, CT:CCP-I. However, in this condition, post-translational processing is incomplete, resulting in mature CT levels that are normal or minimally elevated. In contrast, patients with neuroendocrine cancer have considerably high mature CT levels. Interestingly, although serum CGRP levels often are high in neuroendocrine cancer, they are low in SIRS/sepsis. The marked hyperprocalcitonemia of SIRS/sepsis is probably a consequence of the pro-inflammatory cytokine cascade, and appears to be secreted in a constitutive fashion; the cell(s) of origin of this remarkable hypersecretion is unknown. There is a very marked positive correlation between serum levels of ProCT and nProCT, and the lower level of sensitivity for nProCT may make its measurement a more useful marker for early or mild SIRS/sepsis.
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For a few years, data on SPECT-imaging of dopamine transporters with the cocaine derivate [123I](1R)-2-beta-carbomethoxy-3-beta-(4-iodophenyl)-tropane ([123I] beta-CIT) have been reported mostly in healthy subjects or animals. This study reflects our preliminary results with SPECT-imaging of dopamine transporters using the cocaine analogue 123-beta-CIT in patients with untreated (de novo) parkinsonism. ⋯ 123I-beta-CIT seems to be a promising tool in imaging of untreated parkinsonian patient.
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Comparative Study
The ethics of scientific research: an analysis of focus groups of scientists and institutional representatives.
Little is known about scientists' views on normative research ethics and how these compare with the views of the institutional representatives (IRs) involved in matters of scientific conduct. We qualitatively evaluated scientist and IR perceptions of the norms of science, ethical violations and their harms, factors contributing to violations, and approaches to improve scientific conduct. ⋯ Scientists in these focus groups upheld a complex set of norms that mirror prior codes of science and exceed national misconduct rules. The sharply contrasting views of scientists and IRs concerning responsibility to report misconduct, the utility of misconduct investigation, and penalties for misconduct highlight areas where open discussion and constructive resolution are needed to formulate a functional mechanism to enhance the ethical conduct of science.
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To characterize the New Orleans tuberculosis (TB) patient population and determine what factors might influence outcome, we followed inpatients with active disease at a large, public hospital who then received outpatient treatment at a public clinic. ⋯ Efforts to improve TB control should focus on increasing compliance, particularly among the homeless. Although expansion of DOT is essential, raising therapy completion rates to acceptable levels may require additional social services, financial incentives and enforceable legal remedies for noncompliance. More rigorous treatment guidelines are needed to assure consistent management of patients who receive interrupted treatment.