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排序方式: 共有310条查询结果,搜索用时 218 毫秒
41.
Muhammad Furqan Bari Martin O. Weickert Kavitha Sivakumar Sean G. James David R. J. Snead Bee Kang Tan Harpal Singh Randeva Claire Cecile Bastie Manu Vatish 《PloS one》2014,9(7)
Recently soluble CD163 (sCD163), a cleaved form of the macrophage receptor CD163, was identified as a macrophage-specific risk-predictor for developing Type 2 Diabetes. Here, we investigate circulating levels of sCD163 in gestational diabetes mellitus (GDM). Furthermore, given the role of the placenta in the pathogenesis of GDM, we assessed placental contribution to sCD163 secretion. Paired maternal (venous) and umbilical vein blood samples from GDM (n = 18) and Body Mass Index (BMI) matched control women (n = 20) delivered by caesarean section at 39–40 week gestation were assessed for circulating levels of sCD163, Tumour necrosis factor alpha (TNF-α) and Interleukin 6 (IL-6). Media from explant culture of maternal subcutaneous fat and corresponding placental tissues were assayed for these same molecules. CD163 positive cell numbers were determined in placental and adipose tissues of GDM and control women. We found significantly elevated circulating sCD163 levels in GDM mothers (688.4±46.9 ng/ml vs. 505.6±38.6 ng/ml) and their offspring (418.2±26.6 ng/ml vs. 336.3±24.4 ng/ml [p<0.05 for both]) as compared to controls, together with elevated circulating TNF-α and IL-6 levels. Moreover, both GDM placentae (268.1±10.8 ng/ml/mg vs. 187.6±20.6 ng/ml/mg) and adipose explants (41.1±2.7 ng/ml/mg vs. 26.6±2.4 ng/ml/mg) released significantly more sCD163 than controls. Lastly, significantly more CD163 positive cells were observed in GDM placentae (25.7±1.1 vs. 22.1±1.2) and adipose tissue (19.1±1.1 vs 12.7±0.9) compared to controls. We describe elevated sCD163 levels in GDM and identify human placenta as a novel source of sCD163 suggesting that placental tissues might contribute to the increased levels of circulating sCD163 in GDM pregnancies. 相似文献
42.
Md Monayem Hossain Most Amena Khatun Md Najmul Haque Md Azizul Bari Md Firoz Alam Abul Mandal 《International journal of phytoremediation》2018,20(8):796-804
Arsenic (As) is a phytotoxic element causing health hazards. This work investigates whether and how silicon (Si) alleviates As toxicity in wheat. The addition of Si under As-stress significantly improved morphophysiological characteristics, total protein, and membrane stability compared to As-stressed plants, suggesting that Si does have critical roles in As detoxification in wheat. Analysis of arsenate reductase activity and phytosiderophore (PS) release reveals their no involvement in the Si-mediated alleviation of As in wheat. Furthermore, Si supplementation in As-stressed plants showed a significant increase of As in roots but not in shoots compared with the plants grown under As stress. Further, gene expression analysis of two chelating molecules, TaPCS1 (phytochelatin synthase) and TaMT1 (metallothionein synthase) showed significant induction due to Si application under As stress compared with As-stressed plants. It is consistent with the physiological observations and suggests that alleviation of As toxicity in rice might be associated with As sequestration in roots leading to reduced As translocation in shoots. Furthermore, increased catalase, peroxidase, and glutathione reductase activities in roots imply the active involvement of reactive oxygen species scavenging for protecting wheat plants from As-induced oxidative injury. The study provides mechanistic evidence on the beneficial effect of Si on As toxicity in wheat plants. 相似文献
43.
Marcin Górecki Maria Annunziata M. Capozzi Gianluigi Albano Cosimo Cardellicchio Lorenzo Di Bari Gennaro Pescitelli 《Chirality》2018,30(1):29-42
Three β‐keto sulfoxides ( 1–3 ) were synthesized in enantiopure form and investigated by means of circular dichroism (CD) spectroscopy, both in electronic and vibrational range (ECD, VCD), in combination with quantum chemical calculations. For compound 2 , the X‐ray structure was available; thus, the ECD in the solid state was also considered to reveal the differences between the molecular species in both states. Despite the simplicity of all β‐keto sulfoxides under investigation (29 atoms), reproducing even the major spectral VCD features failed for two compounds, making the use of VCD not ideal to assign their absolute configuration in a reliable way. We demonstrated, however, that the use of ECD spectroscopy, both in solution and solid state, can easily, unambiguously, and without any complication simulate all bands by applying the standard protocol for calculations. This study may stimulate the debate on the need of the use of two chiroptical methods simultaneously in the determination of absolute configurations. 相似文献
44.
Zinc deficiency tolerance in maize is associated with the up‐regulation of Zn transporter genes and antioxidant activities 下载免费PDF全文
M. A. Khatun M. M. Hossain M. A. Bari K. M. Abdullahil M. S. Parvez M. F. Alam A. H. Kabir 《Plant biology (Stuttgart, Germany)》2018,20(4):765-770
- Zinc (Zn) is an essential micronutrient for the growth and development of plants. However, Zn deficiency is a common abiotic stress causing yield loss in crop plants. This study elucidates the mechanisms of Zn deficiency tolerance in maize through physiological and molecular techniques.
- Maize lines tolerant (PAC) and sensitive (DAC) to Zn deficiency were examined physiologically and by atomic absorption spectrometry (AAS). Proteins, H2O2, SOD, POD, membrane permeability and gene expression (using real‐time PCR) of roots and shoots of both maize lines were assessed.
- Zn deficiency had no significant effect on root parameters compared with control plants in PAC and DAC but showed a substantial reduction in shoot parameters in DAC. AAS showed a significant decrease in Zn concentrations in both roots and shoots of DAC but not PAC under Zn deficiency, implying that Zn deficiency tolerance mechanisms exist in PAC. Consistently, total protein and membrane permeability were significantly reduced in DAC but not PAC in both roots and shoots under Zn deficiency in comparison with Zn‐sufficient plants. Real‐time PCR showed that expression of ZmZIP1, ZmZIP4 and ZmIRT1 transporter genes significantly increased in roots of PAC, but not in DAC due to Zn deficiency compared with controls. The H2O2 concentration dramatically increased in roots of DAC but not PAC. Moreover, tolerant PAC showed a significant increase in POD and SOD activity due to Zn deficiency, suggesting that POD‐ and SOD‐mediated antioxidant defence might provide tolerance, at least in part, under Zn deficiency in PAC.
- This study provides an essential background for improving Zn biofortification of maize.
45.
M J Kogan M E Mora S E Bari J Iturraspe J Awruch J M Delfino 《Bioorganic & medicinal chemistry》1999,7(7):1309-1319
Unlike bilirubin IXalpha (1), the isomers bilirubin IXdelta (2) and neobilirubin IXbeta (3) do not require conjugation with glucuronic acid in order to be excreted. A conformational analysis employing an optimized Monte Carlo method and a mixed Monte Carlo stochastic dynamics reveals that isomer 2 exhibits a structure more closed than the well known 'ridge-tile' conformation of 1. The change in the position of both propionic acid chains causes the loss of at least four hydrogen bonds. On the other hand, the change in the configuration of the distal dipyrrinone and the blockage of the lactamic nitrogen by the presence of a bridge in isomer 3 results in an open and more elongated structure, where the chance of hydrogen bond formation in this region is obliterated. The resulting molecular models for these compounds are consistent with 1H NM R, UV-vis, and TLC data. 相似文献
46.
Incorporation and intraparticulate hydrolysis of 131 I-albumin by liver and kidney of an amphibian (Bufo arenarum) 总被引:1,自引:0,他引:1
After a single injection of formaldehyde-treated 131 I-albumin into the heart, the incorporation of the labelled protein by liver (% of total injected radioactivity/% of body weight of the organ) was far greater than in other organs. In kidney and spleen it was respectively six and three times greater than in lungs, intestine, testis and fatty body. No radioactivity was found in brain. The radioactivity in liver and kidney reached a peak 30 minutes after the injection, and quickly decreased during the following four hours. In the 27,000 g × ten minute particles recovered from liver homogenates of animals sacrificed at various times after injection, the rate of 131 I-albumin hydrolysis in vitro and the percentage of trichloroacetic acid soluble radioactivity at zero time of incubation showed different stages of intraparticulate hydrolytic activity. The incorporation and intraparticulate hydrolysis in toad kidney was very low if compared with that of toad liver or mouse kidney; however the catheptic specific activity in toad kidney doubles that of mouse kidney. Isolated toad liver was perfused with total blood, containing 131 I-albumin, for five hours at 22°C in a special chamber. In this conditions, 16% of the labelled albumin was hydrolyzed by the liver. 相似文献
47.
Habibul Bari Shozib Md. Mariful Islam Sultan Abu Saleh Mahmud Md. Nazmul Bari Nasima Akter Saima Jahan Shakir Hosen Mohammad Nazir Hossain A.H.M. Nurun Nabi Muhammad Ali Siddiquee Md. Manjurul Haque 《Saudi Journal of Biological Sciences》2021,28(12):7472-7480
BackgroundBlack pericarp rice has recently become popular among rice consumers for its diverse health benefits specially anti-cancer effect. Cyanidin-3-Glucosides (C3G), an prominant bioactive component of anthocyanins which is abundantly present in black pericarp rice.ObjectivesWe investigated, how effectively it can be used to fortify Cyanidin-3-Glucosides (C3G) content in red and white pericarp polished rice or rice based bakery products for more nutritional value.MethodIn the present study, we have characterized several black pericarp rice cultivars along with some red pericarp and white pericarp rice cultivars by physicochemical including mineral profiling, and quantified the C3G by UFLC and LCMS.ResultsC3G content was significantly reduced from raw rice to cooked rice condition. All the black pericarp rice cultivars synthesized C3G, while this content was not detected in red and white pericarp rice cultivars. However, when 25% of black pericarp rice were mixed with 75% red or white pericarp polished rice, C3G content was significantly retained in cooked rice conditions. Formulation of rice-based bakery food product using black pericarp rice powder was also remarkably retained the C3G content as compared to that of cooking. Black rice is harder in texture, difficult to digest and needs higher energy for cooking. Therefore, we tried to circumvent these challenges by fortifying 25% of black pericarp rice with white or red pericarp rice.ConclusionFortification of C3G enriched black rice (25%) with red or white pericarp rice (75%) might bring a better nutritional quality in both cooking and baking condition. This may lead a way to the effective management of the non-communicable disease such as cancer for common rice consuming population. 相似文献
48.
Angela Picerno Alessandra Stasi Rossana Franzin Claudia Curci Ighli di Bari Loreto Gesualdo Fabio Sallustio 《World journal of stem cells》2021,13(11):1714-1732
Nowadays, it is clear that adult stem cells, also called as tissue stem cells, play a central role to repair and maintain the tissue in which they reside by their self-renewal ability and capacity of differentiating into distinct and specialized cells. As stem cells age, their renewal ability declines and their capacity to maintain organ homeostasis and regeneration is impaired. From a molecular perspective, these changes in stem cells properties can be due to several types of cell intrinsic injury and DNA aberrant alteration (i.e epigenomic profile) as well as changes in the tissue microenviroment, both into the niche and by systemic circulating factors. Strikingly, it has been suggested that aging-induced deterioration of stem cell functions may play a key role in the pathophysiology of the various aging-associated disorders. Therefore, understanding how resident stem cell age and affects near and distant tissues is fundamental. Here, we examine the current knowledge about aging mechanisms in several kinds of adult stem cells under physiological and pathological conditions and the principal aging-related changes in number, function and phenotype that determine the loss of tissue renewal properties. Furthermore, we examine the possible cell rejuvenation strategies. Stem cell rejuvenation may reverse the aging phenotype and the discovery of effective methods for inducing and differentiating pluripotent stem cells for cell replacement therapies could open up new possibilities for treating age-related diseases. 相似文献
49.
Ontogenetic plasticity of anatomical and ecophysiological traits and their correlations in Iris pumila plants grown in contrasting light conditions 下载免费PDF全文
Stevan Avramov Danijela Miljković Nataša Barišić Klisarić Uroš Živković Aleksej Tarasjev 《Plant Species Biology》2017,32(4):392-402
To better understand what directs and limits the evolution of phenotype, constraints in the realization of the optimal phenotype need to be addressed. That includes estimations of variability of adaptively important traits as well as their correlation structures, but also evaluation of how they are affected by relevant environmental conditions and development phases. The aims of this study were to analyze phenotypic plasticity, genetic variability and correlation structures of important Iris pumila leaf traits in different light environments and ontogenetic phases, and estimate its evolutionary potential. Stomatal density, specific leaf area, total chlorophyll concentration and chlorophyll a/b ratio were analyzed on I. pumila full‐sib families in the seedling phase and on the same plants after 3 years of growth in contrasting light conditions typical for ontogenetic stage in question. There was a significant phenotypic plasticity in both ontogenetic stages, but significant genetic variability was detected only for chlorophyll concentrations. Correlations of the same trait between different stages were weak due to changes in environmental conditions and difference in ontogenetic reaction norms of different genotypes. Ontogenetic variability of correlation structures was detected, where correlations and integration were higher in seedlings compared with adult plants 3 years later. Correlations were affected by environmental conditions, with integration being higher in the lower light conditions, but correlations between phases being stronger in the higher light treatment. These findings demonstrated that the analyzed traits can be selected and can mostly evolve independently in different environments and ontogenetic stages, with low genetic variability as a potentially main constraint. 相似文献
50.
The CD spectra of the series PhCH(Me)R, with R = Et (1), nPr (2), iPr (3), and tBu (4), are reported (1-3 for the first time) at room temperature in the 185-280 nm range and at 183 K. These purely hydrocarbon compounds represent the simplest chiral systems containing the phenyl chromophore and exhibit Cotton effects exclusively allied with the benzene transitions. The bands in 1La and 1Lb regions were checked against the available sector rules, with discordant outcomes. Time-dependent density-functional theory calculations, with various functionals and basis sets tested, correctly reproduced the prominent CD bands observed for 1-4. 相似文献