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141.
SNA (Sensitive to Na+) proteins form a membrane protein family, which, in the yeast Saccharomyces cerevisiae, is composed of four members: Sna1p/Pmp3p, Sna2p, Sna3p and Sna4p. In this study, we focused on the 79 residue Sna2p protein. We found that Sna2p is localized in the vacuolar membrane. Directed mutagenesis showed that two functional tyrosine motifs YXXØ are present in the C‐terminal region. Each of these is involved in a different Golgi‐to‐vacuole targeting pathway: the tyrosine 65 motif is involved in adaptor protein (AP‐1)‐dependent targeting, whereas the tyrosine 75 motif is involved in AP‐3‐dependent targeting. Moreover, our data suggest that these motifs also play a crucial role in the exit of Sna2p from the endoplasmic reticulum (ER). Directed mutagenesis of these tyrosines led to a partial redirection of Sna2p to lipid bodies, probably because of a decrease in ER exit efficiency. Sna2p is the first yeast protein in which two YXXØ motifs have been identified and both were shown to be functional at two different steps of the secretory pathway, ER exit and Golgi‐to‐vacuole transport.  相似文献   
142.
Matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) play a role in the development of obesity by contributing to adipogenesis, angiogenesis, and extracellular matrix degradation. We have evaluated a potential functional role of TIMP‐1, which inhibits most MMPs, in in vivo adipogenesis. Therefore, human (h) TIMP‐1 was overexpressed by injection in the tail vein of NUDE mice of an adenoviral vector 3 days before injection of 3T3‐F442A preadipocytes in the back. After 4 weeks of high‐fat diet, the de novo formed fat was analyzed. Overexpression of hTIMP‐1 had no effect on de novo formed fat pad mass. However, the blood vessel density of the fat pads from mice overexpressing hTIMP‐1 was significantly lower than in controls (587 ± 11 mm?2 vs. 806 ± 20 mm?2, P < 0.0001) whereas the adipocytes were somewhat larger (1,477 ± 44 µm2 vs. 1,285 ± 32 µm2, P = 0.03). Thus, in vivo hTIMP‐1 overexpression did not significantly affect the extent of de novo adipose tissue formation, but was associated with significantly lower blood vessel density.  相似文献   
143.
During the early stages of germination and vegetative development,cotyledons of intact bean (Phaseolus vulgaris L.) seedlingsshowed active ABA catabolism causing a low endogenous ABA content.At the end of the substrate mobilizing phase, when the cotyledonsbecame senescent, a drastic increase of the endogenous ABA contentlinked with a decrease of the ABA catabolic activity was observed.This indicates that a close connection exists between senescenceand endogenous ABA content and metabolism in bean cotyledons. Removal of the apical growth region induced in the cotyledonsactivation of the ABA catabolism and the endogenous ABA concentrationdecreased below the detection limit (0.1 ng/g fr wt) at theonset of the outgrowth of the axillary buds. From then, apicaldominance was restored and the cotyledons returned to the senescentstate, which was correlated with a drastic increase of theirendogenous ABA content. 1 Bevoegd verklaard navorser N. F. W. O. 2 Wetenschappelijk medewerker F. K. F. O. (Received November 25, 1980; Accepted February 13, 1981)  相似文献   
144.
145.

Background

Ad35.CS.01 is a pre-erythrocytic malaria candidate vaccine. It is a codon optimized nucleotide sequence representing the P. falciparum circumsporozoite (CS) surface antigen inserted in a replication deficient Adenovirus 35 backbone. A Phase 1a trial has been conducted in the USA in naïve adults and showed that the vaccine was safe. The aim of this study is to assess the safety and immunogenicity of ascending dosages in sub Saharan Africa.

Methods

A double blind, randomized, controlled, dose escalation, phase Ib trial was conducted in a rural area of Balonghin, the Saponé health district (Burkina Faso). Forty-eight healthy adults aged 18-45 years were randomized into 4 cohorts of 12 to receive three vaccine doses (day 0, 28 and 84) of 109, 1010, 5X1010, 1011 vp of Ad35.CS.01 or normal saline by intra muscular injection. Subjects were monitored carefully during the 14 days following each vaccination for non serious adverse events. Severe and serious adverse events were collected throughout the participant study duration (12 months from the first vaccination). Humoral and cellular immune responses were measured on study days 0, 28, 56, 84, 112 and 140.

Results

Of the forty-eight subjects enrolled, forty-four (91.7%) received all three scheduled vaccine doses. Local reactions, all of mild severity, occurred in thirteen (27.1%) subjects. Severe (grade 3) laboratory abnormalities occurred in five (10.4%) subjects. One serious adverse event was reported and attributed to infection judged unrelated to vaccine. The vaccine induced both antibody titers and CD8 T cells producing IFNγ and TNFα with specificity to CS while eliciting modest neutralizing antibody responses against Ad35.

Conclusion

Study vaccine Ad35.CS.01 at four different dose levels was well-tolerated and modestly immunogenic in this population. These results suggest that Ad35.CS.01 should be further investigated for preliminary efficacy in human challenge models and as part of heterologous prime-boost vaccination strategies.

Trial Registration

ClinicalTrials.gov NCT01018459 http://clinicaltrials.gov/ct2/show/NCT01018459  相似文献   
146.
Paleodemographers have developed several methods for estimating the age structure of historical populations in absence of civil registration data. Starting from biological indicators alone, they use a reference population of known sex and age to assess the conditional distribution of the biological indicator given age. However, the small amount of data available and the unstable nature of the related statistical problem mean that most methods are disappointing. Using the most reliable reference data possible, we propose a simple statistical method, integrating the maximum amount of information included in the actual data, which quite significantly improves age estimates for a buried population. Here the method is applied to a French cemetery used from Late Antiquity to the end of the Early Middle Ages. Am J Phys Anthropol, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
147.
148.
Oxydative cyclization of lapachol was attempted by feeding this compound into the culture broth of Beauveria sulfurescens and two ionophore-producing strains of Streptomyces albus and Streptomyces griseus. As a result, three compounds were obtained, lomatiol, lomatic acid and lomatiol acetate, only with B. sulfurescens and S. albus. The structures of these products were determinated by NMR and mass spectrometry. The stereochemistry is given by a comparison with butene analogs.  相似文献   
149.

Introduction

Despite the evidence for preventing childhood morbidity and mortality, financial resources are cited as a constraint for Governments to scale up the key health interventions in some countries. We evaluate the cost effectiveness of implementing IMNCI program in India from a health system and societal perspective.

Methods

We parameterized a decision analytic model to assess incremental cost effectiveness of IMNCI program as against routine child health services for infant population at district level in India. Using a 15-years time horizon from 2007 to 2022, we populated the model using data on costs and effects as found from a cluster-randomized trial to assess effectiveness of IMNCI program in Haryana state. Effectiveness was estimated as reduction in infant illness episodes, deaths and disability adjusted life years (DALY). Incremental cost per DALY averted was used to estimate cost effectiveness of IMNCI. Future costs and effects were discounted at a rate of 3%. Probabilistic sensitivity analysis was undertaken to estimate the probability of IMNCI to be cost effective at varying willingness to pay thresholds.

Results

Implementation of IMNCI results in a cumulative reduction of 57384 illness episodes, 2369 deaths and 76158 DALYs among infants at district level from 2007 to 2022. Overall, from a health system perspective, IMNCI program incurs an incremental cost of USD 34.5 (INR 1554) per DALY averted, USD 34.5 (INR 1554) per life year gained, USD 1110 (INR 49963) per infant death averted. There is 90% probability for ICER to be cost effective at INR 2300 willingness to pay, which is 5.5% of India’s GDP per capita. From a societal perspective, IMNCI program incurs an additional cost of USD 24.1 (INR 1082) per DALY averted, USD 773 (INR 34799) per infant death averted and USD 26.3 (INR 1183) per illness averted in during infancy.

Conclusion

IMNCI program in Indian context is very cost effective and should be scaled-up as a major child survival strategy.  相似文献   
150.

Background

Food-based approaches such as biofortification are meant to sustainably address micronutrient deficiencies in poor settings. Knowing more about micronutrient intakes and deficiencies is a prerequisite to designing and evaluating interventions.

Objective

The objectives of the study were to assess biological status and dietary intakes of iron, zinc and vitamin A among women and children aged 36–59 months in rural Burkina Faso and to study relationships between intake and status to better inform future food-based interventions.

Design

A cross-sectional survey was carried out in two rural provinces of Burkina Faso on a random cluster sample of 480 mother-child pairs. Dietary data was obtained by 24-hour recalls repeated on a random sub-selection of 37.5% of subjects to allow calculation of nutrient’s probability of adequacy (PA). Biomarkers were measured on a sub-sample of 180 mother-child pairs. Blood samples were analyzed for hemoglobin, serum ferritin, soluble transferrin receptors (sTfR), C-reactive protein, alpha-1-glycoprotein, serum zinc concentration (SZnC) and retinol. For each micronutrient the relationship between biomarker and dietary intake was investigated by multiple linear regression models accounting for inflammatory biomarkers.

Results

Mean PA for iron, zinc and vitamin A was 0.49, 0.87 and 0.21 among women and 0.61, 0.95 and 0.33 among children, respectively. Prevalence of anemia, corrected low serum ferritin and high sTfR was 37.6%, 4.0% and 77.5% among women and 72.1%, 1.5% and 87.6% among children, respectively. Prevalence of low SZnC and corrected low serum retinol was 39.4% and 12.0% among women and 63.7% and 24.8% among children, respectively. There was a tendency for a positive relationship between vitamin A intakes and serum retinol among women (β = 0.0003, P = 0.06). Otherwise, no link was found between micronutrients biomarkers and intakes.

Conclusion

Our study depicted different images of micronutrient deficiencies when based on dietary intakes or biomarkers results, thus highlighting the need for more suitable biomarkers and more precise measures of absorbable micronutrient intakes at the individual level. It thus points to challenges in the design and evaluation of future biofortification or other food-based interventions in rural areas of Burkina Faso.  相似文献   
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