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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.
The essential oils of fresh leaves, twigs, and/or fruits of spicebush cultivated in Oregon (field distilled) and Delaware (laboratory distilled) are examined by GC/MS. The oil of leaves of spicebush is notably high in 6-methyl-5-hepten-2-one (1.94% in Oregon to 34.83 ± 9.69% in Delaware). β-caryophyllene (15.26% in Oregon to 48.44 ± 1.35% in Delaware), and/or (E)-nerolidol (10.20% in Oregon to 12.05 ± 2.02% in Delaware). The oil of the twigs of spicebush is notably high in 1,8-cineole (45.41 ± 0.35% in Delaware), while the oil of the fruits is notably high in a-phellandrene (64.62 ± 0.66% in Delaware) and β-phellandrene (11.23+0.17% in Delaware).  相似文献   
4.
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   
5.
We have previously shown that a fraction of yeast copper/zinc-superoxide dismutase (SOD1) and its copper chaperone CCS localize to the intermembrane space of mitochondria. In the present study, we have focused on the mechanism by which SOD1 is partitioned between cytosolic and mitochondrial pools. Using in vitro mitochondrial import assays, we show that only a very immature form of the SOD1 polypeptide that is apo for both copper and zinc can efficiently enter the mitochondria. Moreover, a conserved disulfide in SOD1 that is essential for activity must be reduced to facilitate mitochondrial uptake of SOD1. Once inside the mitochondria, SOD1 is converted to an active holo enzyme through the same post-translational modifications seen with cytosolic SOD1. The presence of high levels of CCS in the mitochondrial intermembrane space results in enhanced mitochondrial accumulation of SOD1, and this apparently involves CCS-mediated retention of SOD1 within mitochondria. This retention of SOD1 is not dependent on copper loading of the enzyme but does require protein-protein interactions at the heterodimerization interface of SOD1 and CCS as well as conserved cysteine residues in both molecules. A model for how CCS-mediated post-translational modification of SOD1 controls its partitioning between the mitochondria and cytosol will be presented.  相似文献   
6.

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   
7.
Cell chemotaxis is frequently required in normal or pathological situations such as invasion, metastasis, and tumor angiogenesis and may involve many different cell types. At present, no device can simultaneously (i) make morphological observations, (ii) quantify cell migration, (iii) test multiple chemoattracting gradients, and (iv) analyze cell-cell interactions. We developed an agarose-based assay to address these questions. Two glass molds were designed, around which agarose gel could be poured to form specific well shapes. Using a vital nuclear stain (Hoechst 33258), we characterized the migration profile of adherent or suspension cells. Cells could be observed during the entire migration process. We were able to follow cells moving toward chemoattractants or being repulsed by other molecules, and we could estimate average migration speed. Using this inexpensive assay, we were able to obtain precise, reproducible results concerning the chemotactic behavior of different cell types. The resulting data differentiated between chemokinetic and chemotactic movement. Chemotactic potencies could be compared using different criteria, such as the number of attracted cells, induced speed, and morphological aspect. This improved agarose assay appears to be a reliable and inexpensive alternative to other available chemotaxis study tools.  相似文献   
8.
9.
Survival and development of tumors depends on nutritional and respiratory biological events and exchanges ensured by blood and lymph. Tumor proliferation is associated with an increase in the vascular networks either near the tumor or intra-tumorally. Tumor tissues are able to increase their provisionment according to their needs while directing and optimizing the development of peri-tumoral vessels. The production of growth factors stimulating neo-formation of lymphatic vessels by cancer cells constitutes one of the adaptations responsible for metastatic propagation. During tumor development the lymphatic system is considered in many cases of cancer as the primary means of metastasis dissemination. The study of the lymphatic system setting and ways to block it are important points to consider in oncology.  相似文献   
10.

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   
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