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Studies were conducted to determine whether encephalomyocarditis virus infection causes proteolytic cleavage of any of the polypeptides which comprise eucaryotic initiation factor 4F. Since no such alterations in the components of the initiation factor were detected, these observations confirmed that the mechanisms whereby encephalomyocarditis virus and poliovirus shut off host translation are different.  相似文献   
53.

Background

Anemia affects over 500 million women, and in pregnancy is associated with impaired maternal and infant outcomes. Intermittent antenatal iron supplementation is an attractive alternative to daily dosing; however, the impact of this strategy on infant outcomes remains unclear. We compared the effect of intermittent antenatal iron supplementation with daily iron supplementation on maternal and infant outcomes in rural Viet Nam.

Methods and Findings

This cluster randomised trial was conducted in Ha Nam province, Viet Nam. 1,258 pregnant women (<16 wk gestation) in 104 communes were assigned to daily iron–folic acid (IFA), twice weekly IFA, or twice weekly multiple micronutrient (MMN) supplementation. Primary outcome was birth weight. Mean birth weight was 3,148 g (standard deviation 416). There was no difference in the birth weights of infants of women receiving twice weekly IFA compared to daily IFA (mean difference [MD] 28 g; 95% CI −22 to 78), or twice weekly MMN compared to daily IFA (MD −36.8 g; 95% CI −82 to 8.2). At 32 wk gestation, maternal ferritin was lower in women receiving twice weekly IFA compared to daily IFA (geometric mean ratio 0.73; 95% CI 0.67 to 0.80), and in women receiving twice weekly MMN compared to daily IFA (geometric mean ratio 0.62; 95% CI 0.57 to 0.68), but there was no difference in hemoglobin levels. Infants of mothers who received twice weekly IFA had higher cognitive scores at 6 mo of age compared to those who received daily IFA (MD 1.89; 95% CI 0.23 to 3.56).

Conclusions

Twice weekly antenatal IFA or MMN did not produce a clinically important difference in birth weight, when compared to daily IFA supplementation. The significant improvement in infant cognitive outcomes at 6 mo of age following twice weekly antenatal IFA requires further exploration, and provides additional support for the use of intermittent, rather than daily, antenatal IFA in populations with low rates of iron deficiency.

Trial registration

Australia New Zealand Clinical Trials Registry 12610000944033 Please see later in the article for the Editors'' Summary  相似文献   
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Molecular and Cellular Biochemistry - Ginseng is commonly used as an herbal medicine for improvement of life quality. It is also used as a supplemental medication with anti-cancer drugs to enhance...  相似文献   
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Background

The Kato-Katz thick smear (Kato-Katz) is the diagnostic method recommended for monitoring large-scale treatment programs implemented for the control of soil-transmitted helminths (STH) in public health, yet it is difficult to standardize. A promising alternative is the McMaster egg counting method (McMaster), commonly used in veterinary parasitology, but rarely so for the detection of STH in human stool.

Methodology/Principal Findings

The Kato-Katz and McMaster methods were compared for the detection of STH in 1,543 subjects resident in five countries across Africa, Asia and South America. The consistency of the performance of both methods in different trials, the validity of the fixed multiplication factor employed in the Kato-Katz method and the accuracy of these methods for estimating ‘true’ drug efficacies were assessed. The Kato-Katz method detected significantly more Ascaris lumbricoides infections (88.1% vs. 75.6%, p<0.001), whereas the difference in sensitivity between the two methods was non-significant for hookworm (78.3% vs. 72.4%) and Trichuris trichiura (82.6% vs. 80.3%). The sensitivity of the methods varied significantly across trials and magnitude of fecal egg counts (FEC). Quantitative comparison revealed a significant correlation (Rs >0.32) in FEC between both methods, and indicated no significant difference in FEC, except for A. lumbricoides, where the Kato-Katz resulted in significantly higher FEC (14,197 eggs per gram of stool (EPG) vs. 5,982 EPG). For the Kato-Katz, the fixed multiplication factor resulted in significantly higher FEC than the multiplication factor adjusted for mass of feces examined for A. lumbricoides (16,538 EPG vs. 15,396 EPG) and T. trichiura (1,490 EPG vs. 1,363 EPG), but not for hookworm. The McMaster provided more accurate efficacy results (absolute difference to ‘true’ drug efficacy: 1.7% vs. 4.5%).

Conclusions/Significance

The McMaster is an alternative method for monitoring large-scale treatment programs. It is a robust (accurate multiplication factor) and accurate (reliable efficacy results) method, which can be easily standardized.  相似文献   
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Some infants sleep facedown for long periods with no ill effects, whereas others become hypoxemic. Rebreathing of expired air has been determined by CO(2) measurement; however, O(2) levels under such conditions have not been determined. To evaluate this and other factors influencing inspired gas concentrations, we studied 21 healthy infants during natural sleep while facedown on soft bedding. We measured gas exchange with the environment and bedding, ventilatory response to rebreathing, and concentrations of inspired CO(2) and O(2). Two important factors influencing inspired gas concentrations were 1) a variable seal between bedding and infants' faces and 2) gas gradients in the bedding beneath the infants, with O(2)-poor and CO(2)-rich air nearest to the face, fresher air distal to the face, and larger tidal volumes being associated with fresher inspired air. Minute ventilation increased significantly while rebreathing because of an increase in tidal volume, not frequency. The measured drop in inspired O(2) was significantly greater than the accompanying rise in inspired CO(2). This appears to be due to effects of the respiratory exchange ratio and differential tissue solubilities of CO(2) and O(2) during unsteady conditions.  相似文献   
59.
We have investigated the potential antiviral activity of three cobalt(III) compounds. Two compounds, Co(III)-cyclen-methylbenzoic acid and its methyl ester derivative, are based on the macrocyclic chelator, cyclen, and were synthesized in our laboratory. Both compounds have been shown to bind tightly to nucleic acids and to hydrolyze phosphodiester bonds. However, neither compound exhibited any significant antiviral activity in an in vitro model of Sindbis virus replication. In contrast, a third compound, Co(III)hexammine, significantly inhibited Sindbis virus replication in baby hamster kidney (BHK) cells in a dose- and time-dependent manner. In plaque assays, the incubation of Co(III)hexammine with Sindbis virus resulted in a dose-dependent decrease in virus replication when measured at both 24 and 48-h post-infection. Over the concentration range of 0-5mM Co(III)hexammine, the IC(50) for the inhibition of viral replication was determined to be 0.10+/-0.04mM at 48h. Additionally, when BHK cell monolayers were pretreated with Co(III)hexammine for 6h prior to Sindbis infection, optimal cellular morphology and plasma membrane integrity were observed at 0.6-1.2mM Co(III)hexammine. Analysis by flow cytometry confirmed that Co(III)hexammine mediated a concomitant dose-dependent increase in BHK cell viability and a decrease in the percentage of Sindbis virus-infected cells (IC(50)=0.13+/-0.04mM). Our findings demonstrate for the first time that Co(III)hexammine possesses potent antiviral activity. We discuss our findings within the context of the ability to further functionalize Co(III)hexammine to render it a highly specific antiviral therapeutic reagent.  相似文献   
60.
Gel microdroplet – fluorescence activated cell sorting (GMD-FACS) is an innovative high throughput screening platform for recombinant protein libraries, and we show here that GMD-FACS can overcome many of the limitations associated with conventional screening methods for antibody libraries. For example, phage and cell surface display benefit from exceptionally high throughput, but generally require high quality, soluble antigen target and necessitate the use of anchored antibody fragments. In contrast, the GMD-FACS assay can screen for soluble, secreted, full-length IgGs at rates of several thousand clones per second, and the technique enables direct screening against membrane protein targets in their native cellular context. In proof-of-concept experiments, rare anti-EGFR antibody clones were efficiently enriched from a 10,000-fold excess of anti-CCR5 clones in just three days. Looking forward, GMD-FACS has the potential to contribute to antibody discovery and engineering for difficult targets, such as ion channels and G protein-coupled receptors.  相似文献   
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