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51.
Marginal zinc deficiency (MZD) exists in children of industrialized societies and impairs growth and development. MZD is believed to be one of the most common deficiencies, even though there is no data available on its global prevalence. This is partly because of the lack of sensitivity and specificity of serum zinc, the most commonly used biomarker of zinc status, to detect MZD. In children, MZD is always accompanied by a decrease in hair zinc. This cross-sectional study was designed to explore if there are any associations between some socio-demographic and behavioral variables with hair zinc status in an attempt to understand the social determinants of MZD and the profile of at risk children. Our citywide survey (n = 719) indicated a mean hair zinc of 116 ± 43 μg/g with 17% below the cutoff. Logistic regression analysis indicated that age, maternal education, number of adults at home, being described as “eating unhealthy”, and Child Behavior Questionnaire scores of “activity level” as the significant predictors of hair zinc status. Our study provides important information on the hair zinc status of Vancouver preschoolers and some factors in children and their environment associated with hair zinc, which may help in better understanding of hair zinc as a biomarker of MZD.  相似文献   
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Fresh leaves of 150 individuals from 15 populations representing five putative species of Stachys sect. Fragilicaulis, subsect. Fragiles distributed in the Zagros mountains in western Iran were analyzed for isoenzyme variation. Four enzyme systems (peroxidase, esterase, superoxide dismutase and ascorbate peroxidase) have been studied and a total of 32 bands representing seven putative loci have been analyzed by UPGMA using the Euclidean distances. UPGMA analysis resulted in the recognition of three distinct clusters among the considered populations. The average value of Shannon diversity index (H′) estimated for each population ranged from 0.05 to 2.17. The mean number of bands per isoenzyme ranges from 1.60 to 2.50. The value of Euclidean distance ranges from 0.85 to 3.79. The analysis of isoenzyme variation patterns suggests recognizing following species in Stachys sect. Fragilicaulis subsect. Fragiles: Stachys benthamiana (including Stachys megalodonta), Stachys kurdica (including Stachys ballotiformis) and Stachys asterocalyx. These data also suggest paying more attention to geographical distribution of taxa in Stachys for their taxonomic delimitation. This study provides another strong support for application of electrophoretic analysis of isoenzymes in taxonomy at species level.  相似文献   
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Although monocytes can be directed to develop into dendritic cells (DC) in vitro, the molecular mechanisms that induce their transformation in vivo are largely unknown. In the present study we employed an in vivo SCID mouse model to investigate the impact of two proinflammatory chemotaxins, the anaphylatoxin C5a and the chemokine macrophage inflammatory protein-1alpha (CCL3), on the differentiation of human monocytes and immature DC generated from monocytes in the presence of GM-CSF and IL-4. Both C5a and macrophage inflammatory protein-1alpha recruited human monocytes and immature DC into the peritoneal cavity of SCID mice, but only C5a induced their differentiation into phenotypically mature DC by 48 h after injection. Macrophages derived from monocytes by in vitro culture were resistant to C5a-mediated transformation in vivo. The effect of C5a was indirect, since C5a-stimulated TNF-alpha and PGE(2) were found to be obligatory as well as sufficient to induce differentiation of monocytes. In contrast to monocytes, in vitro generated immature DC required TNF-alpha, but not PGE(2), for their C5a-mediated maturation in vivo. C5a-transformed monocytes represented an inflammatory type of DC, as they constitutively secreted high amounts of TNF-alpha, but also retained the capacity to release the Th1 cytokine IL-12 p70 upon stimulation with CD40 ligand. In summary, we identified for the first time a cascade of inflammatory signals that can induce the transformation of monocytes into DC in vivo. This novel function emphasizes the important immunoregulatory role of C5a at the interface of innate and adaptive immunity.  相似文献   
55.
The Arabidopsis thaliana genes PROTEIN INHIBITOR OF ACTIVATED STAT LIKE1 (PIAL1) and PIAL2 encode proteins with SP-RING domains, which occur in many ligases of the small ubiquitin-related modifier (SUMO) conjugation pathway. We show that PIAL1 and PIAL2 function as SUMO ligases capable of SUMO chain formation and require the SUMO-modified SUMO-conjugating enzyme SCE1 for optimal activity. Mutant analysis indicates a role for PIAL1 and 2 in salt stress and osmotic stress responses, whereas under standard conditions, the mutants show close to normal growth. Mutations in PIAL1 and 2 also lead to altered sulfur metabolism. We propose that, together with SUMO chain binding ubiquitin ligases, these enzymes establish a pathway for proteolytic removal of sumoylation substrates.  相似文献   
56.
Cardiovascular diseases are known as one of major causes of morbidity and mortality worldwide. Despite the many advancement in therapies are associated with cardiovascular diseases, it seems that finding of new therapeutic option is necessary. Cell therapy is one of attractive therapeutic platforms for treatment of a variety of diseases such as cardiovascular diseases. Among of various types of cell therapy, stem cell therapy has been emerged as an effective therapeutic approach in this area. Stem cells divided into multipotent stem cells and pluripotent stem cells. A large number studies indicated that utilization of each of them are associated with a variety of advantages and disadvantages. Multiple lines evidence indicated that stem cell therapy could be used as suitable therapeutic approach for treatment of cardiovascular diseases. Many clinical trials have been performed for assessing efficiency of stem cell therapies in human. However, stem cell therapy are associated with some challenges, but, it seems resolving of them could contribute to using of them as effective therapeutic approach for patients who suffering from cardiovascular diseases. In the current review, we summarized current therapeutic strategies based on stem cells for cardiovascular diseases. J. Cell. Biochem. 119: 95–104, 2018. © 2017 Wiley Periodicals, Inc.  相似文献   
57.
Background:In the field of recombinant protein production, downstream processing, especially protein purification, is critical and often the most expensive step. Carbohydrate binding module 64 (CBM64) was shown in 2011 to bind efficiently to a broad range of cellulose materials.Methods:In this study, we developed a protein purification method using nanocrystalline cellulose embedded in a polyacrylamide monolith cryogel and CBM64 affinity tag linked by intein to PD1 as a model protein. The CBM64-Intein-PD1 gene cassette was expressed in E. coli. Following cell lysis, CBM64-Intein-PD1 protein bound to the monolith PA-NCC cryogel. After washing and reducing the pH from 8.0 to 6.5, the intein underwent self-cleavage, resulting in the release and elution of pure PD1 protein.Results:The synthesized monolith column had a porous structure with an average pore size of 30 µm and a maximum binding capacity of 497 µg per gram of dried column. The yield of this purification method was 84%, while the yield of the His tag-acquired CBM64-Intein-PD1 method was 89%.DiscussionWe used cellulose as support for affinity chromatography, which can be used as a cost-effective method for protein purification.Key Words: Affinity tag, CBM64, PD1, Protein purification  相似文献   
58.
The aggressive and highly metastatic nature of triple-negative breast cancer (TNBC) causes patients to suffer from the poor outcome. HIF-1 signalling pathway is a prominent pathway that contributes to angiogenesis and metastasis progression in tumours. On the contrary, the undeniable importance of circular RNAs (circRNAs) as multifunctional non-coding RNAs (ncRNAs) has been identified in breast cancer. These ncRNAs owing to their high stability and specificity have been becoming a hotspot in cancer researches. circRNAs act as competing endogenous RNAs (ceRNAs) and compete with mRNAs for shared miRNAs, thus modulate gene expression. Since the most dysregulated biological functions in TNBC are associated with cellular invasion, understanding the molecular pathogenesis of these processes is a crucial step towards the development of new treatment approaches. The purpose of this study is to undermine the circRNA-associated ceRNA network involved in HIF-1 signalling in TNBC using an integrative bioinformatics approach. In the next step, the novel circ_0047303-mediated ceRNA regulatory axes have been extracted and validated across TNBC samples. We show that circ_0047303 has the highest degree in the circRNA-associated ceRNA network and shows a significant up-expression in TNBC. Moreover, our results suggest that circ_0047303 could mediate the upregulation of key angiogenesis-related genes, including HIF-1, EIF4E2 and VEGFA in TNBC through sponging the tumour-suppressive miRNAs. The circ_0047303 could be a promising molecular biomarker and/or therapeutic target for TNBC.  相似文献   
59.
Aim Increases in annual mean temperature in the course of current climate change are expected to facilitate mass species migration towards higher altitudes and latitudes. However, this migration may be slowed, or even temporarily reversed, by infrequent and unpredictable episodes of low winter temperatures. Iran experienced a severe cold wave in January and February 2008, giving an opportunity to observe the effects on a large number of woody plant species, many growing further north than their natural ranges. Location The study was carried out in the National Botanical Garden of Iran (35°44′20.06″ N; 51°10′25.66″ E). Method To estimate the damage caused to each individual woody plant in the garden, we adopted the following protocol; at the start of the growing season, at the end of March and beginning of April 2008, all woody species were inspected for damage. In the case of evergreens this took the form of obvious damage to foliage, usually manifested as severe browning. In the case of deciduous species, damage was recognized by the failure of all or part of the plant to produce new leaves; all affected individual plants were labelled. In July all labelled plants were rechecked and, based on whole or partial above‐ground die‐back, a final list of damaged individuals was produced. Results As expected, the majority of native and exotic species introduced from cold temperate habitats showed no freezing injuries. Many woody species in the garden were damaged or killed, despite their previous survival and growth, in many cases for up to 40 years. The majority of taxa (101 out of a total of 145) that suffered freezing‐induced damage were evergreens. Main conclusions The results indicate that despite an increase in mean annual temperature, unpredictable lethal cold waves may retard the expansion of plants towards higher altitudes and latitudes. Broadleaved evergreen species from warm climates were particularly badly affected, with many species suffering high rates of mortality.  相似文献   
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