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121.
The Arabidopsis genome encodes a family of inositol 1,3,4-trisphosphate 5/6-kinases which form a subgroup of a larger group of ATP-grasp fold proteins. An analysis of the inositol 1,3,4-trisphosphate 5/6-kinase family might, ultimately, be best rewarded by detailed comparison of related enzymes in a single genome. The enzyme encoded by At2G43980, AtITPK4; is an outlier to its family. At2G43980 is expressed in male and female organs of young and mature flowers. AtITPK4 differs from other family members in that it does not display inositol 3,4,5,6-tetrakisphosphate 1-kinase activity; rather, it displays inositol 1,4,5,6-tetrakisphosphate and inositol 1,3,4,5-tetrakisphosphate isomerase activity.  相似文献   
122.
123.
Nine phenolic compounds, such as cis-/trans-p-coumaric acid, cis-/trans-p-coumaric acid methyl ester, glucose ester of cis-/trans-p-coumaric acid, caffeic acid methyl ester, kaempferol 7-O-beta-D-glucoside and kaempferol 3-O-beta-D-glucoside, were isolated from Lavatera trimestris flowers by chromatographic techniques and their structures were elucidated by spectral means (NMR). All compounds were tested for their antioxidant activity, while the methanolic extract was tested also for its antimicrobial activity. Also several non-polar constituents have been identified using GC and GC/MS methods. This is the first time that phenolic esters and non-polar constituents were identified in the flowers of L. trimestris L.  相似文献   
124.
Amniotic fluid has been recently suggested as an alternative source of mesenchymal stem cells. However, the fate of amniotic fluid-derived mesenchymal stem cells (AF-MSCs) after in vivo transplantation has yet to be determined. In the present study we explored whether human AF-MSCs could survive and migrate following transplantation into the striatum of normal and ischemic rat. We found that the grafted cells could survive and migrate towards multiple brain regions in the normal animals, while they moved towards the injured region in the ischemic rat. Double-immunostaining analyses showed that the implanted human AF-MSCs express markers for immature neurons (Doublecortin) at 10 days, and for astrocytes (GFAP) at 10, 30 and 90 after transplantation. This study provides the first evidence that human amniotic fluid contains cells having the potential to survive and integrate into adult rat brain tissue and, therefore, to function as effective stem cells for therapeutic strategies.  相似文献   
125.
The main objective of this study was to isolate lactic acid bacteria from kefir grains and investigate their probiotic potential. In this study, 48 bacterial strains were isolated from kefir grains, whereas 39 strains were categorized to the genus Lactobacillus. Evaluation of the probiotic potential of the isolated stains was performed, including resistance to low pH, tolerance to pepsin, pancreatin and bile salts, and antibiotic resistance. In addition, evaluation of adhesion and antiproliferative properties in in vitro experimental systems was also conducted. Strains SP2 and SP5 that displayed the best performance in the conducted in vitro tests were selected for further studies. Firstly, genotypic identification of the two strains was performed by partial 16S rRNA gene sequencing, BLAST analysis, and species-specific multiplex PCR assay. The two strains were confirmed to be Pediococcus pentosaceus SP2 and Lactobacillus paracasei SP5. Then, the adhesion properties of the two strains were examined in vitro. Both strains displayed substantial adherence capacity to HT-29 human colon cancer cells. Moreover, a significant decrease of HT-29 cell growth after treatment with viable P. pentosaceus SP2 or L. paracasei SP5 was recorded. In addition, downregulation of anti-apoptotic genes and over-expression of cell cycle–related genes was recorded by real-time PCR analysis. Treatment with conditioned media of the two strains also caused significant reduction of cancer cell proliferation in a time- and concentration-dependent manner. P. pentosaceus SP2 and L. paracasei SP5 displayed the best probiotic properties that exerted substantial adherence on human colon cancer cells as well as significant anti-proliferative properties.  相似文献   
126.
The ability to monitor the activation state of T‐cells during immunotherapy is of great importance. Although specific activation markers do exist, their abundance and complicated regulation cannot definitely define the activation state of the cells. Previous studies have shown that Third Harmonic Generation (THG) imaging could distinguish between activated versus resting microglia and healthy versus cancerous cells, mainly based on their lipid‐body profiles. In the present study, mitogen or antigen‐stimulated T‐cells were subjected to THG imaging microscopy. Qualitative and quantitative analysis showed statistically significant increase of THG mean area and intensity in activated versus resting T‐cells. The connection of THG imaging to chemical information was achieved using Raman spectroscopy, which showed significant differences between the activation processes and controls, correlating of THG signal area with cholesterol and lipid compounds, but not with triglycerides. The obtained results suggested a potential employment of nonlinear microscopy in evaluating of T‐cell activation, which is expected to be largely appreciated in the clinical practice.   相似文献   
127.
Introduction: Proteomic analyses have been acknowledged to carry a significant prospective in elucidating the pathogenesis of several diseases, including osteoarthritis (OA). But it has not been an easy road: major technical issues, mainly derived from the complex and rigid nature of the cartilage tissue, had to be faced; an obstacle that led to the development of different approaches.

Areas covered: In this review, we categorized the proteomic studies undertaken (proteomic analyses of the cartilage, cartilage explants, cultured chondrocytes, and chondrocytes’ secretome) as part of the different strategies developed in order to overcome tissue and disease-specific challenges. Essentially these approaches aimed at identifying differences in the proteome of healthy vs diseased tissue. Our aim was to point out the novel players that have emerged from these analyses and highlight the associated mechanism(s) suggested to play a role in the pathogenesis of OA.

Expert commentary: The identified factors indicate the implication of age-associated mechanisms, such as metabolic deregulation, inflammation, and redox imbalance, in OA onset and/or progression. Taken together these results outline the causal network of the disease and place chondrocytes’ senescence at the center of the emerging aetiopathological atlas.  相似文献   

128.
Rapid tumor growth can establish metabolically stressed microenvironments that activate 5′-AMP-activated protein kinase (AMPK), a ubiquitous regulator of ATP homeostasis. Previously, we investigated the importance of AMPK for the growth of experimental tumors prepared from HRAS-transformed mouse embryo fibroblasts and for primary brain tumor development in a rat model of neurocarcinogenesis. Here, we used triple-negative human breast cancer cells in which AMPK activity had been knocked down to investigate the contribution of AMPK to experimental tumor growth and core glucose metabolism. We found that AMPK supports the growth of fast-growing orthotopic tumors prepared from MDA-MB-231 and DU4475 breast cancer cells but had no effect on the proliferation or survival of these cells in culture. We used in vitro and in vivo metabolic profiling with [13C]glucose tracers to investigate the contribution of AMPK to core glucose metabolism in MDA-MB-231 cells, which have a Warburg metabolic phenotype; these experiments indicated that AMPK supports tumor glucose metabolism in part through positive regulation of glycolysis and the nonoxidative pentose phosphate cycle. We also found that AMPK activity in the MDA-MB-231 tumors could systemically perturb glucose homeostasis in sensitive normal tissues (liver and pancreas). Overall, our findings suggest that the contribution of AMPK to the growth of aggressive experimental tumors has a critical microenvironmental component that involves specific regulation of core glucose metabolism.  相似文献   
129.
In an attempt to investigate the significance of lipid peroxidation in the pathogenesis of gastritis associated with or without Helicobacter pylori infection, malonodialdehyde (MDA) levels were measured by the thiobarbiturate assay in the gastric juice of 101 patients undergoing upper GI endoscopy and correlated with histopathological findings. Elevated MDA levels were found in all patients with gastritis compared with controls. MDA levels were significantly correlated with the extent of the mucosal inflammation and with disease activity in patients with reactive gastritis. In patients with H. pylori associated gastritis MDA levels were not correlated with disease activity but rather with the degree of atrophy. In this case, MDA levels were equal or even less than in patients with reactive gastritis. MDA levels were not affected by the history of consumption of PPIs, of H(2)-blockers or of NSAIDs over the last month before the endoscopy. It is concluded that lipid peroxidation is a mechanism involved in the pathogenesis of gastritis associated or not to H. pylori infection.  相似文献   
130.
Runella slithyformis Larkin and Williams 1978 is the type species of the genus Runella, which belongs to the Cytophagaceae, a family that was only recently classified to the order Cytophagales in the class Cytophagia. The species is of interest because it is able to grow at temperatures as low as 4°C. This is the first completed genome sequence of a member of the genus Runella and the sixth sequence from the family Cytophagaceae. The 6,919,729 bp long genome consists of a 6.6 Mbp circular genome and five circular plasmids of 38.8 to 107.0 kbp length, harboring a total of 5,974 protein-coding and 51 RNA genes and is a part of the Genomic Encyclopedia of Bacteria and Archaea project.  相似文献   
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