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71.
BACKGROUND: Hepatitis virus(es) that are neither hepatitis B (HBV) nor hepatitis C (HCV) (non-B, non-C [NBNC]) may be transmitted by transfusion. The present study assessed donor values for alanine aminotransferase (ALT) and antibody to hepatitis B core antigen (anti- HBc) for their association with HCV and NBNC hepatitis outcomes among allogeneic blood recipients. STUDY DESIGN AND METHODS: Data on blood donors and recipients enrolled in the Transfusion- Transmitted Viruses Study in four United States cities from 1974 through 1980 were supplemented by anti-HBc testing of donors and anti-HCV evaluation of recipients. Two statistical approaches estimated the value of these indirect tests in detecting donors associated with HCV seroconversion and NBNC hepatitis in recipients. RESULTS: For HCV cases, donor ALT alone (at > or = 60 IU/L) had a sensitivity and a specificity of 30 and 96 percent, respectively, and anti-HBc alone (at > or = 60% inhibition) had a sensitivity and specificity of 53 and 86 percent, respectively. The two markers combined had a sensitivity and a specificity of 69 and 83 percent. For NBNC hepatitis cases, each measure had low sensitivity (20%) that was not improved by using both (28%) [corrected]. CONCLUSION: The indirect tests proved to be equal in sensitivity to the first-generation anti-HCV tests. The positive predictive power of these indirect tests in the 1980s was sufficient to affect HCV incidence in studies during that period. Improved anti-HCV assays, however, replaced the need for indirect tests. The sensitivity of indirect tests for NBNC hepatitis contributed little.  相似文献   
72.
OBJECTIVE: To search for novel genes contributing to adiposity in familial combined hyperlipidemia (FCH), a disorder characterized by abdominal obesity, hyperlipidemia and insulin resistance, using a 10cM genome-wide scan. DESIGN: Plasma leptin and soluble tumor necrosis factor receptor superfamily members 1A and 1B (sTNFRSF1A and sTNFRSF1B, also known as sTNFR1 and sTNFR2) were analyzed as unadjusted and adjusted quantitative phenotypes of adiposity, in addition to body mass index (BMI), in multipoint and single-point analyses. In the second stage of analysis, an important chromosome 1 positional candidate gene, the leptin receptor (LEPR), was studied. SUBJECTS: Eighteen Dutch pedigrees with familial combined hyperlipidemia (FCH) (n= 198) were analyzed to search for chromosomal regions harboring genes contributing to adiposity. RESULTS: Multipoint analysis of the genome scan data identified linkage (log of odds, LOD, 3.4) of leptin levels to a chromosomal region defined by D1S3728 and D1S1665, flanking the leptin receptor (LEPR) gene by approximately 9 and 3 cM, respectively. The LOD score decreased to 1.8 with age- and gender-adjusted leptin levels. Notably, BMI also mapped to this region with an LOD score of 1.2 (adjusted BMI: LOD 0.5). Two polymorphic DNA markers in LEPR and their haplotypes revealed linkage to unadjusted and adjusted BMI and leptin, and an association with leptin levels was found as well. In addition, the marker D8S1110 showed linkage (LOD 2.8) with unadjusted plasma concentrations of soluble TNFRSF1A. BMI gave a LOD score of 0.6. Moreover, a chromosome 10 q-ter locus, AFM198ZB, showed linkage with adjusted BMI (LOD 3.3). CONCLUSION: These data provide evidence that a human chromosome 1 locus, harboring the LEPR gene, contributes to plasma leptin concentrations, adiposity and body weight in humans affected with this insulin resistant dyslipidemic syndrome. Novel loci on chromosome 8 and 10 qter need further study.  相似文献   
73.

Background  

After the WHO issued the global alert for 2009 pandemic influenza A (H1N1), many national health agencies began to screen travelers on entry in airports, ports and border crossings to try to delay local transmission.  相似文献   
74.

Background  

Patients with diabetic polyneuropathy (DPN) are often confronted with ulceration of foot soles. Increased plantar pressure under the forefoot has been identified as a major risk factor for ulceration. This study sets out to test the hypothesis that changes in gait characteristics induced by DPN related muscle weakness are the origin of the elevated plantar pressures.  相似文献   
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Low yield and insufficient purity limit the transplantation of human islets of Langerhans. In the rat, a new technique to isolate the islets of Langerhans was developed by intraarterial infusion of iron particles into the islet capillaries. After digestion the iron-loaded islets were purified with magnetic retraction (MR). In the present study, 10 human pancreata not suitable for clinical use were arterially injected with an iron-oxide suspension. After injection a small piece was used for histological analysis, and the tail was intraductally perfused with collagenase and manually digested. The yield was compared with 11 pancreata processed in the standard way. Nine of 10 pancreata were successfully injected with iron-oxide and digested. After MR, enrichment was achieved but the purity was not more than 50%. Similar results between the 2 groups were obtained regarding digestion times (23 +/- 1.1 vs 22.7 +/- 1.5 minutes) and purification yields (1749 +/- 502.1 vs 2111 +/- 501.8 IE/g, P = .6) for the MR vs control groups, respectively. Histological analysis revealed that 60% to 88% of the islets contained iron aggregations with substantially higher concentrations compared with the exocrine tissue. In conclusion, iron-oxide did not influence the isolation outcome before purification. Islet purification with MR gave enrichment but no pure fractions.  相似文献   
77.
BACKGROUND: We previously demonstrated the involvement of the Ca2+-independent protein kinase C-delta (PKC-delta) isoform in sevoflurane-induced cardioprotection against ischaemia and reperfusion (I/R) injury. Since sevoflurane is known to modulate myocardial Ca2+-handling directly, in this study we investigated the role of the Ca2+-dependent PKC-alpha isoform in sevoflurane-induced cardioprotective signalling in relation to reactive oxygen species (ROS), adenosine triphosphate-sensitive mitochondrial K+ (mitoK+(ATP)) channels, and PKC-delta. METHODS: Preconditioned (15 min 3.8 vol% sevoflurane) isolated rat right ventricular trabeculae were subjected to I/R, consisting of 40 min superfusion with hypoxic, glucose-free buffer, followed by normoxic glucose-containing buffer for 60 min. After reperfusion, contractile recovery was expressed as percentage of force development before I/R. The role of PKC-alpha, ROS, mitoK+(ATP) channels, and PKC-delta was established using the following pharmacological inhibitors: Go6976 (GO; 50 nM), n-(2-mercaptopropionyl)-glycine (MPG; 300 microM), 5-hydroxydecanoic acid sodium (5HD; 100 microM), and rottlerin (ROT; 1 microM). RESULTS: Preconditioning of trabeculae with sevoflurane improved contractile recovery after I/R [65 (3)% (I/R + SEVO) vs 47 (3)% (I/R); n = 8; P < 0.05]. This cardioprotective effect was attenuated in trabeculae treated with GO [42 (4)% (I/R + SEVO + GO); P > 0.05 vs (I/R)]. In sevoflurane-treated trabeculae, PKC-alpha translocated towards mitochondria, as shown by immunofluorescent co-localization analysis. GO and MPG, but not 5HD or ROT, abolished this translocation. CONCLUSIONS: Sevoflurane improves post-ischaemic contractile recovery via activation of PKC-alpha. ROS production, but not opening of mitoK+(ATP) channels, precedes PKC-alpha translocation towards mitochondria. This study shows the involvement of Ca2+-dependent PKC-alpha in addition to the well-established role of Ca2+-independent PKC isoforms in sevoflurane-induced cardioprotection.  相似文献   
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Concentrations of p,p'-DDT, p,p'-DDE, and p,p'-DDD were determined in serum of members of households of two different areas of KwaZulu. Annual intradomiciliary application of DDT is used for the interruption of malaria transmission in one area (the exposed group) while the other served as the control. Demographic differences between the two groups resulted in significantly more females in the control group. The two groups were comparable with respect to age. Serum from household members living in DDT-treated dwellings had significantly higher (p less than .005) levels of sigma DDT and metabolites (mean sigma DDT 140.9 micrograms/l) than those from the control area (mean sigma DDT 6.04 micrograms/l). Percentage DDT was also significantly higher (p less than .05) in the exposed group (28.9%) than the control group (8.3%). sigma DDT for the 3-10 yr age interval (168.6 micrograms/l) was significantly higher (p less than .05) than the 20-29 (60.5 micrograms/l) and 30-39 (84.2 micrograms/l) yr age intervals. There seemed to be two groups with regard to accumulation and elimination. The age group 3-29 appeared to be eliminating DDT, most likely accumulated from contaminated breast milk, faster than they accumulated it. From around 29 yr of age accumulation predominated as the levels increased with age. Regression analysis suggested pharmacokinetic differences for DDE and DDT between the two groups. Liver function parameters between the two groups only differed significantly for gamma-glutamyl transferase (gamma GT) (p less than .005), but the influence of difference in alcohol consumption, which was significantly higher in the exposed group (p less than .0001), offered a better explanation. Those of the exposed group that consumed alcohol had a significantly higher (p less than .05) mean gamma GT level (41.5 IU/l) than those that did not (20.2 IU/l), but were not significantly different for sigma DDT (p greater than .05). The safety of DDT used in malaria control for subjects aged 3 and older was confirmed by the levels of DDT in serum when compared with other studies, which showed lack of any negative effects associated with these levels in adults, and an apparently normal liver function in the exposed and control groups.  相似文献   
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