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1.
PGRP-S (Tag7) is an innate immunity protein involved in the antimicrobial defense systems, both in insects and in mammals. We have previously shown that Tag7 specifically interacts with several proteins, including Hsp70 and the calcium binding protein S100A4 (Mts1), providing a number of novel cellular functions. Here we show that Tag7–Mts1 complex causes chemotactic migration of lymphocytes, with NK cells being a preferred target. Cells of either innate immunity (neutrophils and monocytes) or acquired immunity (CD4+ and CD8+ lymphocytes) can produce this complex, which confirms the close connection between components of the 2 branches of immune response.  相似文献   
2.
34Fusarium graminearum Schw isolates produced 4-deoxynivalenol to form significant amounts of 4, 7 — dideoxynivalenol and lesser amounts of 4 — deoxynivalenol monoacetates on grain substratesin vitro. This is the first report on the capability a large group of naturally occurring isolates to produce 4,7-dideoxynivalenol. The average levels of 4,7-dideoxynivalenol on rice, corn, barley, and wheat as a substrate were respectively 26.8, 14.0, 12.8, and 10.5% of the level of 4-deoxynivalenol. 4, 7 — dideoxynivalenol was present in all examined naturally contaminated wheat kernel samples at levels of 1.7 to 7.9% of the level of 4-deoxynivalenol. These findings suggest that more attention should be given to the occurrence of 4,7-dideoxynivalenol in cereals.  相似文献   
3.
Objectives Somatoform disorders are common in international primary care settings, but have been little studied in the developing world. The objective of this study was to determine the prevalence of severe undifferentiated somatoform disorder, and its relationship to depression and anxiety, among patients attending walk-in clinics in Trinidad.Methods The study participants, who were all aged 18 years or older and attending walk-in clinics at 16 randomly selected health centres, were surveyed between May and August 2007 using the PRIME-MD questionnaire.Results There were 594 participants (the response rate was 92%), of whom 72.7% were female. Their ages ranged from 18 to 93 years, and 54.5% were over 50 years of age. In total, 37.2% were married and 25.9% were single. Indo-Trinidadians represented 43.1% and Afro-Trinidadians represented 36% of the study sample; 56.5% of the participants reported that their income was less than US$ 400 per month, and 65.7% were unemployed. At walk-in clinics in Trinidad, the estimated prevalence of severe undifferentiated somatoform disorder was 10.3% (95% CI: 7.86–12.74), that of hypochondriasis was 28.5% (95% CI: 24.9–32.1), and that of body dysmorphic disorder was 15.8% (95% CI: 11.9–18.7). Severe undifferentiated somatoform disorder was statistically significantly associated with gender and ethnicity but not with age, level of education, employment status or income. Chi-square testing found significant associations between the presence of severe undifferentiated somatoform disorder and both depression and anxiety (P < 0.05), between hypochondriasis and both anxiety and depression (P < 0.05), and between body dysmorphic disorder and depression (P < 0.05) but not anxiety. Regression analysis suggested that the demographic features that predicted severe undifferentiated somatoform disorder were being female or Indo-Trinidadian.Conclusions Walk-in clinics in Trinidad that serve older patients on a lower income have a high proportion of patients with somatoform disorders as measured by the PRIME-MD scale. These patients exhibit many features of anxiety and depression. These findings have implications for medical training and service delivery.  相似文献   
4.

Background  

Phylogenetic hypotheses of higher-level relationships in the order Charadriiformes based on morphological data, partly disagree with those based on DNA-DNA hybridisation data. So far, these relationships have not been tested by analysis of DNA sequence data. Herein we utilize 1692 bp of aligned, nuclear DNA sequences obtained from 23 charadriiform species, representing 15 families. We also test earlier suggestions that bustards and sandgrouses may be nested with the charadriiforms. The data is analysed with methods based on the parsimony and maximum-likelihood criteria.  相似文献   
5.

Background

Immunocompromised patients are vulnerable to severe or complicated influenza infection. Vaccination is widely recommended for this group. This systematic review and meta-analysis assesses influenza vaccination for immunocompromised patients in terms of preventing influenza-like illness and laboratory confirmed influenza, serological response and adverse events.

Methodology/Principal Findings

Electronic databases and grey literature were searched and records were screened against eligibility criteria. Data extraction and risk of bias assessments were performed in duplicate. Results were synthesised narratively and meta-analyses were conducted where feasible. Heterogeneity was assessed using I2 and publication bias was assessed using Begg''s funnel plot and Egger''s regression test. Many of the 209 eligible studies included an unclear or high risk of bias. Meta-analyses showed a significant effect of preventing influenza-like illness (odds ratio [OR] = 0.23; 95% confidence interval [CI] = 0.16–0.34; p<0.001) and laboratory confirmed influenza infection (OR = 0.15; 95% CI = 0.03–0.63; p = 0.01) through vaccinating immunocompromised patie nts compared to placebo or unvaccinated controls. We found no difference in the odds of influenza-like illness compared to vaccinated immunocompetent controls. The pooled odds of seroconversion were lower in vaccinated patients compared to immunocompetent controls for seasonal influenza A(H1N1), A(H3N2) and B. A similar trend was identified for seroprotection. Meta-analyses of seroconversion showed higher odds in vaccinated patients compared to placebo or unvaccinated controls, although this reached significance for influenza B only. Publication bias was not detected and narrative synthesis supported our findings. No consistent evidence of safety concerns was identified.

Conclusions/Significance

Infection prevention and control strategies should recommend vaccinating immunocompromised patients. Potential for bias and confounding and the presence of heterogeneity mean the evidence reviewed is generally weak, although the directions of effects are consistent. Areas for further research are identified.  相似文献   
6.

Background

Aluminum (Al) toxicity is an important limitation to food security in tropical and subtropical regions. High Al saturation on acid soils limits root development, reducing water and nutrient uptake. In addition to naturally occurring acid soils, agricultural practices may decrease soil pH, leading to yield losses due to Al toxicity. Elucidating the genetic and molecular mechanisms underlying maize Al tolerance is expected to accelerate the development of Al-tolerant cultivars.

Results

Five genomic regions were significantly associated with Al tolerance, using 54,455 SNP markers in a recombinant inbred line population derived from Cateto Al237. Candidate genes co-localized with Al tolerance QTLs were further investigated. Near-isogenic lines (NILs) developed for ZmMATE2 were as Al-sensitive as the recurrent line, indicating that this candidate gene was not responsible for the Al tolerance QTL on chromosome 5, qALT5. However, ZmNrat1, a maize homolog to OsNrat1, which encodes an Al3+ specific transporter previously implicated in rice Al tolerance, was mapped at ~40 Mbp from qALT5. We demonstrate for the first time that ZmNrat1 is preferentially expressed in maize root tips and is up-regulated by Al, similarly to OsNrat1 in rice, suggesting a role of this gene in maize Al tolerance. The strongest-effect QTL was mapped on chromosome 6 (qALT6), within a 0.5 Mbp region where three copies of the Al tolerance gene, ZmMATE1, were found in tandem configuration. qALT6 was shown to increase Al tolerance in maize; the qALT6-NILs carrying three copies of ZmMATE1 exhibited a two-fold increase in Al tolerance, and higher expression of ZmMATE1 compared to the Al sensitive recurrent parent. Interestingly, a new source of Al tolerance via ZmMATE1 was identified in a Brazilian elite line that showed high expression of ZmMATE1 but carries a single copy of ZmMATE1.

Conclusions

High ZmMATE1 expression, controlled either by three copies of the target gene or by an unknown molecular mechanism, is responsible for Al tolerance mediated by qALT6. As Al tolerant alleles at qALT6 are rare in maize, marker-assisted introgression of this QTL is an important strategy to improve maize adaptation to acid soils worldwide.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2164-15-153) contains supplementary material, which is available to authorized users.  相似文献   
7.
African men play important roles in the decisions about family life, including fertility and family planning. However, fertility and family planning research and programmes have ignored their roles in the past, focusing only on women's behaviours. Since the 1994 International Conference on Population and Development (ICPD), interest in men's involvement in reproductive health has increased. Unfortunately, data on their knowledge and use of contraception are generally scanty. This paper examines knowledge and use of contraception among ever-married men in Nigeria. A total of 1451 ever-married men aged 18-55 were interviewed in Imo and Ondo States, Nigeria. The findings reveal that men's level of contraceptive knowledge is high in the study areas. About 90% knew at least one method of family planning. Furthermore, the level of contraceptive use among married men is such that men could participate in family planning activities if there were adequate programmes to involve them. Men in the sample areas were found not only to support their spouses' use of contraceptives, but were actually using condoms to delay or prevent pregnancy. Age, education, place of residence, number of living children and being counselled for family planning were identified as key factors determining contraceptive knowledge and use among married men in the study areas. To ensure increased participation of men in family planning, programmes must be designed to educate them on the need for family size limitation and involve them in service delivery, even if only to their male counterparts.  相似文献   
8.

Background  

The typical antbirds (Thamnophilidae) form a monophyletic and diverse family of suboscine passerines that inhabit neotropical forests. However, the phylogenetic relationships within this assemblage are poorly understood. Herein, we present a hypothesis of the generic relationships of this group based on Bayesian inference analyses of two nuclear introns and the mitochondrial cytochrome b gene. The level of phylogenetic congruence between the individual genes has been investigated utilizing Bayes factors. We also explore how changes in the substitution models affected the observed incongruence between partitions of our data set.  相似文献   
9.
10.
The Michaelis constant of catecholase in 3 cultivars of Dioscorea alata was determined. Oxidative browning was related to the activity of the enzyme in the yams. Inhibition by cysteine was competitive, while 2-mercaptoethanol caused an uncompetitive type of inhibition. On DEAE column chromatography a minor peak preceded the major peak in the fresh yam while a minor peak was eluted after the major peak in the stored yam.  相似文献   
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