Lack of familial clustering of hepatitis C virus infection

BACKGROUND: Although transmission of hepatitis C virus (HCV) through parental exposure is well documented, it is still controversial whether familial clustering of HCV occurs. METHODS: To investigate risk factors for HCV infection, 109 cases and 84 non-infected controls were studied. In addition, 250 family members (104 men, 146 women) of cases and 170 family members of controls (64 men, 106 women) were tested for HCV infection using an anti-HCV antibody, alanine aminotransferase (ALT), and reverse transcribed polymerase chain reaction (RT-PCR). RESULTS: In the case-control analysis, people aged > or =60 were almost three times more likely to be infected by HCV than those aged <40. Risk of HCV infection was most strongly related to a history of blood transfusion (OR = 12.6, 95% CI: 4.3-36.5) followed by a history of jaundice (OR = 4.1, 95% CI: 1.3-12.6). Only one family member of cases and no-one related to the controls had HCV infection. CONCLUSIONS: These results suggest that, in Korea, age and parenteral exposure, such as a blood transfusion, are risk factors for HCV infection and familial clustering of HCV infection, if it occurs, is rare.     

Pharmacokinetics and pharmacodynamics of sibrafiban (Ro 48-3657), an orally active IIb/IIIa antagonist, administered alone or in combination with heparin, aspirin, and recombinant tissue-type plasminogen activator in beagles

OBJECTIVE: The study aimed to determine the effectiveness of prophylactic medical intervention in reducing the incidence of cystoid macular edema (CME) and the effectiveness of medical treatment for chronic CME after cataract surgery. DESIGN: The study design was a systematic review and meta-analysis of published reports of randomized clinical trials (RCTs). PARTICIPANTS: Sixteen RCTs involving 2898 eyes examining the effectiveness of medical prophylaxis of CME and 4 RCTs involving 187 eyes testing the effectiveness of medical treatment of chronic CME were used in the study. INTERVENTIONS: Medical prophylaxis of treatment (cyclo-oxygenase inhibitors or corticosteroids) versus control (placebo or active treatment) was performed. MAIN OUTCOME MEASURES: Incidence of angiographically diagnosed CME, incidence of clinically significant CME, and vision were measured. RESULTS: Thirty-six articles reported testing a prophylactic medical intervention for CME after cataract surgery. The incidence of CME varied extensively across studies and was related to the study design used. Summary odds ratios (OR) indicated that prophylactic intervention was effective in reducing the incidence of both angiographic CME (OR = 0.36; 95% confidence interval [CI] = 0.28-0.45) and clinically relevant CME (OR = 0.49; 95% CI = 0.33-0.73). There also was a statistically significant positive effect on improving vision (OR = 1.97; 95% CI = 1.14-3.41). A combination of the results of the four RCTs testing medical therapy for chronic CME indicated a treatment benefit in terms of improving final visual acuity by two or more Snellen lines (OR = 2.67; 95% CI = 1.35-5.30). Assessment of the quality of the 20 RCTs included in the meta-analyses indicated problems in the design, execution, and reporting of a number of trials. CONCLUSION: A combination of the results from RCTs indicates that medical prophylaxis for aphakic and pseudophakic CME and medical treatment for chronic CME are beneficial. Because most of the RCTs performed to date have problems related to quality, a well-designed RCT is needed to confirm this result, using clinical CME and vision as outcomes.     

The simplified two-pipette technique is more efficient than the conventional three-pipette method for blastomere biopsy in human embryos

Kell and Kx are two quantitatively minor proteins from the human erythrocyte membrane which carry blood groups antigens and are thought to be a metalloprotease and a membrane transporter, respectively. In the red cell membrane, these proteins form a complex stabilized by disulfide bond(s). Phosphorylation status of these proteins was studied, in the presence or absence of effectors of several kinases, either on intact cells incubated with [32P]-orthophosphate or on ghosts incubated with [gamma-32P]ATP. Purification of Kell-Kx complex, by immunochromatography on an immobilized human monoclonal antibody of Kell blood group specificity allowed to establish that (i) neither protein is phosphorylated on tyrosine; (ii) the Kell protein is a putative substrate for Casein Kinase II (CKII) and Casein Kinase I (CKI) but not for protein kinase C (PKC), whereas Kx protein is phosphorylated by CKII and PKC but not by CKI; (iii) Protein Kinase A neither phosphorylates the Kell nor the Kx proteins.     

Dehydration of tetrahydrofuran by pervaporation using crosslinked PVA/PEI blend membranes

Dense blend membranes were prepared by blending hydrophilic polymers poly(vinyl alcohol) (PVA) and poly(ethyleneimine) (PEI), which were then crosslinked by glutaraldehyde (GA) in a mixture of solvents under the catalysis of hydrochloric acid (HCl) for the dehydration of tetrahydrofuran (THF) by pervaporation. The effect of experimental parameters such as feed water concentration, permeate pressure, and membrane thicknesses on permeate parameters, i.e., flux and selectivity were determined with feed water concentration less than 40 wt %. The membranes were found to have good potential for breaking the azeotrope of 94 wt % THF with a flux of 1.072 and 0.376 kg/m² h for plane PVA/PEI and crosslinked PVA/PEI blend membrane, which exhibited high selectivity of 156 and 579 respectively. Selectivity was found to improve with decreasing feed water concentration and increasing membrane thickness, whereas flux decreased correspondingly. High permeate pressure causes a reduction in both flux and selectivity. These effects were clearly elucidated with the aid of the known relationship among plasticization effect, degree of swelling, permeate pressure, and feed water concentration. These blend membranes were also subjected to sorption studies to evaluate the extent of interaction and degree of swelling in pure as well as binary feed mixtures. Further ion exchange capacity studies were carried out for all the crosslinked and uncrosslinked membranes to determine the total number of interacting groups present in the membranes. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 1152–1161, 2006     

Flow Regime Maps for Flow of Liquid Through Downcomer in a Turbulent Bed Contactor

The provision of a downcomer to classical turbulent bed Contactor (TBC) increases the gas treating capacity of the equipment. When the downcomer is provided, it is expected that all the liquid passes through the downcomer only without any liquid flow through the distributor. In the present study, the operational regime for the flow of liquid only through the downcomer is experimentally evaluated for various geometric parameters and particle characteristics. It is observed that the preferred operational regime without dumping and weeping increases with an increase in Archimedes number and downcomer diameter, and decreases with an increase in static bed height and downcomer weir height. Correlations are proposed to satisfactorily predict experimentally observed operational regime.     

Effects of insulin therapy on non-insulin-dependent diabetics with secondary oral hypoglycemic agent failure

A recent trend among physicians is the categorisation of lung scans as normal [excludes pulmonary embolism (PE)], high probability (confirms PE) and non-diagnostic (no judgement on PE risk). The low probability scan is therefore being eliminated as a functional category. This occasional survey contends that such an approach is misguided. Correction of the original PIOPED data with certain assumptions provides a more reproducible, albeit restricted, low probability scan category which excludes PE in 97% of cases in the low pre-test clinical category. Patients with a low probability scan with risk factors for PE (i.e. medium clinical risk) will require further investigation. More important, the very low probability scan category excludes PE in 98% of patients with low and more than 92% of patients with medium pre-test clinical likelihood. The demise of "low probability" is premature.     

Study on effect of diverse air inlet arrangement on thermal management of cylindrical lithium-ion cells

Lithium-ion cells are preferred in the electrical powertrain due to high-power density, compactness, and modularity. In real driving conditions, the cells undergo discharge rates as high as 4 C resulting in high heat generation affecting the performance. To obtain the maximum performance the pack construction and thermal management of cells are crucial parameters. In our work, air-cooled technique with diverse air inlet and staggered scheme with a two-channel partition approach for thermal management of the cylindrical lithium-ion cells are studied in computational fluid dynamics. The simulation model is validated with experimental results. The obtained results demonstrate that the cells in the dual-directional air inlet arrangement had low maximum temperature difference among and within the cells and required least fan work. This arrangement required least fan work to generate optimal air inlet velocity of 2 m/s for 1, 2, and 3 C and 4 m/s for 4 C discharge rates. There is a reduction of 50% and 33% fan work for 3 and 4 C discharge rates, which are the majority operating points. Also, it shows that the temperature uniformity within the cells has improved. The results of this study can used to optimize parameters for designing an enhanced thermal management system.     

A Note on Moments of Gamma Order Statistics

Previously quadrature approximations were developed to determine the moments of a distribution of the response of a multivariable function when each of the variables is a random variable from a normal distribution. The error was shown to be of the order of the sixth power of the standard deviations of the random variables, but a more useful bound is desired in applied work. Only limited success has been achieved in this direction. It is shown that the best approximating distribution is a Beta distribution of the first kind with β₂ equal to 3 and mean, variance, and β₁ obtained by quadrature, where β₁ and β₂ are standard measures of skewness and kurtosis, respectively. A parametric study of the function X = C_o (a _o, ± y ₁ ± y ₂ ± … ±y_n ) ^m + b _o where the y_i all have the same standard deviation, σ, is conducted both analytically and by quadrature. The mean and variance obtained by quadrature are essentially exact in the range of interest. It is shown that for a large range of σ the above distribution is both a good approximation and a much better approximation than either a normal approximation with the same mean and variance or a linear approximation. The example also shows that the β₂ obtained by quadrature is a poor indicator of the precision of the quadrature approximation.     

Effect of CoFe2O4 mole percentage on multiferroic and magnetoelectric properties of Na0.5Bi0.5TiO3/CoFe2O4 particulate composites

Na_0.5Bi_0.5TiO₃ (NBT), CoFe₂O₄ (CFO) as well as particulate composites containing different mole percentages of NBT and CFO were synthesized by the solid-state sintering route and characterized for their ferroelectric and ferrimagnetic hysteresis loops, magnetostriction and magnetoelectric (ME) output. The mole% of CFO was found to influence the ferroelectric and ferrimagnetic hysteresis loops as well as magnetostriction and piezomagnetic coefficients which in turn had a significant effect on the magnetoelectric voltage coefficient. The highest magnetoelectric voltage coefficient (α) of 0.5 mV/cm/Oe was recorded in (65) NBT–(35) CFO composite.