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111.
Increasing evidence demonstrates the dissociation of fat deposition, the inflammatory response, and insulin resistance in the development of obesity-related metabolic diseases. As a regulatory enzyme of glycolysis, inducible 6-phosphofructo-2-kinase (iPFK2, encoded by PFKFB3) protects against diet-induced adipose tissue inflammatory response and systemic insulin resistance independently of adiposity. Using aP2-PFKFB3 transgenic (Tg) mice, we explored the ability of targeted adipocyte PFKFB3/iPFK2 overexpression to modulate diet-induced inflammatory responses and insulin resistance arising from fat deposition in both adipose and liver tissues. Compared with wild-type littermates (controls) on a high fat diet (HFD), Tg mice exhibited increased adiposity, decreased adipose inflammatory response, and improved insulin sensitivity. In a parallel pattern, HFD-fed Tg mice showed increased hepatic steatosis, decreased liver inflammatory response, and improved liver insulin sensitivity compared with controls. In both adipose and liver tissues, increased fat deposition was associated with lipid profile alterations characterized by an increase in palmitoleate. Additionally, plasma lipid profiles also displayed an increase in palmitoleate in HFD-Tg mice compared with controls. In cultured 3T3-L1 adipocytes, overexpression of PFKFB3/iPFK2 recapitulated metabolic and inflammatory changes observed in adipose tissue of Tg mice. Upon treatment with conditioned medium from iPFK2-overexpressing adipocytes, mouse primary hepatocytes displayed metabolic and inflammatory responses that were similar to those observed in livers of Tg mice. Together, these data demonstrate a unique role for PFKFB3/iPFK2 in adipocytes with regard to diet-induced inflammatory responses in both adipose and liver tissues.  相似文献   
112.
Enterococcus faecalis is a ubiquitous bacterium of the gut that is observed in persistent periradicular infections. Its pathogenicity is associated with biofilm formation and the ability to survive under nutrient-poor (starvation) conditions. However, characteristics of chemical composition of biofilm cells developed by starved E. faecalis cells remain poorly understood. In this study, E. faecalis cells in exponential, stationary, and starvation phases were prepared and separately cultured to form biofilms. Confocal laser scanning microscopy was performed to verify biofilm formation. Raman microscopy was used to investigate the chemical composition of cells within the biofilms. Compared to cells in exponential or stationary phase, starved cells developed biofilms with fewer culturable cells (P?E. faecalis.  相似文献   
113.
Mice homozygous for targeted disruption of the zinc finger domain of Gli2 (Gli2(zfd/zfd)) die at birth with developmental defects in several organ systems including the skeleton. The current studies were undertaken to define the role of Gli2 in endochondral bone development by characterizing the molecular defects in the limbs and vertebrae of Gli2(zfd/zfd) mice. The bones of mutant mice removed by cesarian section at E16.5 and E18.5 demonstrated delayed endochondral ossification. This was accompanied by an increase in the length of cartilaginous growth plates, reduced bone tissue in the femur and tibia and by failure to develop the primary ossification centre in vertebral bodies. The growth plates of tibiae and vertebrae exhibited increased numbers of proliferating and hypertrophic chondrocytes with no apparent alteration in matrix mineralisation. The changes in growth plate morphology were accompanied by an increase in expression of FGF2 in proliferating chondrocytes and decreased expression of Indian hedgehog (Ihh), patched (Ptc) and parathyroid-hormone-related protein (PTHrP) in prehypertrophic cells. Furthermore, there was a reduction in expression of angiogenic molecules in hypertrophic chondrocytes, which was accompanied by a decrease in chondroclasts at the cartilage bone interface, fewer osteoblasts lining trabecular surfaces and a reduced volume of metaphyseal bone. These results indicate that functional Gli2 is necessary for normal endochondral bone development and that its absence results in increased proliferation of immature chondrocytes and decreased resorption of mineralised cartilage and bone formation.  相似文献   
114.
Ni‐rich Li[NixCoyMn1?x?y]O2 (x ≥ 0.8) layered oxides are the most promising cathode materials for lithium‐ion batteries due to their high reversible capacity of over 200 mAh g?1. Unfortunately, the anisotropic properties associated with the α‐NaFeO2 structured crystal grains result in poor rate capability and insufficient cycle life. To address these issues, a micrometer‐sized Ni‐rich LiNi0.8Co0.1Mn0.1O2 secondary cathode material consisting of radially aligned single‐crystal primary particles is proposed and synthesized. Concomitant with this unique crystallographic texture, all the exposed surfaces are active {010} facets, and 3D Li+ ion diffusion channels penetrate straightforwardly from surface to center, remarkably improving the Li+ diffusion coefficient. Moreover, coordinated charge–discharge volume change upon cycling is achieved by the consistent crystal orientation, significantly alleviating the volume‐change‐induced intergrain stress. Accordingly, this material delivers superior reversible capacity (203.4 mAh g?1 at 3.0–4.3 V) and rate capability (152.7 mAh g?1 at a current density of 1000 mA g?1). Further, this structure demonstrates excellent cycling stability without any degradation after 300 cycles. The anisotropic morphology modulation provides a simple, efficient, and scalable way to boost the performance and applicability of Ni‐rich layered oxide cathode materials.  相似文献   
115.

Background

Whether or not hepatitis B virus (HBV) genotypes, mutations, and viral loads determine outcomes for patients with HBV-induced hepatocellular carcinoma (HCC) remains controversial.

Aims

To study the influence of HBV viral factors on prognoses for patients with HBV-induced HCC after resection surgery and investigate if antiviral therapy could counteract the adverse effects of viral factors.

Methods

A total of 333 HBV-related HCC patients who underwent tumor resection were enrolled retrospectively. Serum HBV DNA levels, mutations, anti-viral therapy, and other clinical variables were analyzed for their association with post-operative recurrence.

Results

After a median follow-up of 45.9 months, 208 patients had HCC recurrence after resection. The 5-year overall survival and recurrence-free survival rates were 55.4% and 35.3%, respectively. Multivariate analysis showed indocyanine green retention rate at 15 minutes >10%, gamma-glutamyltransferase (GGT) level >60 U/L, macroscopic and microscopic venous invasion, and the absence of anti-viral therapy were significant risk factors for recurrence. Anti-viral therapy could decrease recurrence in patients with early stage HCC, but the effect was less apparent in those with the Barcelona-Clinic Liver Cancer stage C HCC. For patients without antiviral therapy after resection, serum HBV DNA levels >106 copies/mL, GGT >60 U/L, and macroscopic and microscopic venous invasion were significant risk factors predicting recurrence. Among the 216 patients without anti-viral therapy but with complete HBV surface gene mapping data, 73 were with pre-S deletion mutants. Among patients with higher serum HBV DNA levels, those with pre-S deletion had significantly higher rates of recurrence. Moreover, multivariate analysis showed multi-nodularity, macroscopic venous invasion, cirrhosis, advanced tumor cell differentiation, and pre-S deletion were significant risk factors predictive of recurrence.

Conclusions

Ongoing HBV viral replication and pre-S deletion are crucial for determining post-operative tumor recurrence. Anti-viral therapy can help reduce recurrence and improve prognosis, especially for those with early stage HCC.  相似文献   
116.
Chemokines participate in various processes of monocyte recruitment including monocyte arrest and migration. Our group and others have demonstrated that growth-related oncogene (GRO)-alpha (CXCL1) can support monocyte arrest in models of inflammation. Here we employed a parallel plate-flow chamber and Transwell reconstitution assay to test whether GRO family chemokines were sufficient for Mono Mac 6 (a human monocytic cell line) and isolated human monocyte recruitment. Our study shows that 1) GRO-alpha, -beta (CXCL2), and -gamma (CXCL3) all act as arrest chemokines for monocyte adhesion on vascular cell adhesion molecule (VCAM)-1 under flow in the presence of P-selectin; 2) CXCR2 is the functional receptor for GRO-family chemokines in monocyte arrest; however, CXCR2 is not an arrest chemokine receptor in general, since epithelial neutrophil-activating peptide ENA-78 failed to arrest monocytes; 3) GRO-alpha, -beta, and -gamma all fail to increase intracellular free Ca2+ or mediate monocyte chemotaxis; and 4) signaling through G alpha(i) protein, phosphoinositide 3-kinase, and actin polymerization but not Ca2+ mobilization or the mitogen-activated kinases p38 and MAPK/extracellular signal-related kinase are necessary for GRO-alpha-mediated Mono Mac 6 cell arrest under flow. We conclude that the GRO-family chemokines are specialized monocyte-arrest chemokines. Their role in monocyte recruitment in inflammation can be inhibited by blocking CXCR2 function or downstream signaling events.  相似文献   
117.
A high-resolution scanning Kelvin nanoprobe is introduced as an alternative technique to the conventional fluorescence and mass spectrometric detection methods currently employed in nucleic acid and protein microarray technology. The new instrument is capable of the highly sensitive discernment of surface biochemical events taking place at molecular level such as nucleic acid hybridization and antibody-antigen interaction. The method involves measurement of changes in work function and surface potential instigated by such interactions. Being a label-free and non-contact technique, the structure, spatial configuration, local properties or function of the molecular system under study are not affected, nor perturbed by intercalating dyes, a strong electric field or ionizing beam. Subsequent to scanning, the microarray can be examined by other alternative approaches. Nucleic acids and proteins have been printed in microarray format on slides with a gold film in place using gold-sulphur interactive chemistry. Hybridization of nucleic acids for complementary and mismatched configurations shows consistent and reproducible values of work function. Differentiation of single internal mismatches is demonstrated. Protein concentration and formation of antibody-antigen pairs can be visualized and examined with high sensitivity and good inter-spot reproducibility.  相似文献   
118.
We employed a genetic approach to determine whether deficiency of 1,25-dihydroxyvitamin D (1,25(OH)2D) and deficiency of the vitamin D receptor (VDR) produce the same alterations in skeletal and calcium homeostasis and whether calcium can subserve the skeletal functions of 1,25(OH)2D and the VDR. Mice with targeted deletion of the 25-hydroxyvitamin D 1alpha-hydroxylase (1alpha(OH)ase-/-) gene, the VDR gene, and both genes were exposed to 1) a high calcium intake, which maintained fertility but left mice hypocalcemic; 2) this intake plus three times weekly injections of 1,25(OH)2D3, which normalized calcium in the 1alpha(OH)ase-/- mice only; or 3) a "rescue" diet, which normalized calcium in all mutants. These regimens induced different phenotypic changes, thereby disclosing selective modulation by calcium and the vitamin D system. Parathyroid gland size and the development of the cartilaginous growth plate were each regulated by calcium and by 1,25(OH)2D3 but independent of the VDR. Parathyroid hormone secretion and mineralization of bone reflected ambient calcium levels rather than the 1,25(OH)2D/VDR system. In contrast, increased calcium absorption and optimal osteoblastogenesis and osteoclastogenesis were modulated by the 1,25(OH)2D/VDR system. These studies indicate that the calcium ion and the 1,25(OH)2D/VDR system exert discrete effects on skeletal and calcium homeostasis, which may occur coordinately or independently.  相似文献   
119.
Two powdery mildew resistance genes were Identified from Aegilops tauschll accessions Y201 and Y212 and mapped using two different F2 populations derived from the crosses between susceptible accession Y2272 and Y201, and susceptible accession Y2263 and Y212. Genetic analysis of resistance to powdery mildew Indicated that the resistance of Y201 was controlled by a single dominant gene, whereas the resistance of Y212 was controlled by a single recessive gene. We have temporarily designated these genes as PmY201 and PmY212, respectively. By bulk segregation analysis, six mlcrosatelllte markers Including Xgwm174, cfd26, cfd57, cfdl02, Xgwm583 and Xgwm639 were found to be linked to PraY201 with genetic distances of 5.2, 7.7, 9.6, 12.5, 20.2 and 22.1 cM, respectively. Five SSR markers, including cfd57, Xgwm182, cfd7, cfd102, and cfd12, were found to be linked to PmY212 with distances of 5.6, 7.2, 11.5, 14.7, and 18.5 cM, respectively. According to the locations of the linked markers, the two resistance genes were located In the 5DL region. Based on the chromosomal locations and the resistance patterns of the two genes, we propose that PmY201 and PmY212 are two novel powdery mildew resistance genes, and are suitable for marker-assisted selection.  相似文献   
120.
We characterized cellular and molecular mechanisms involved in spermatogenesis following short-term heat exposure of murine testis. For these studies, we utilized a proteomic approach with two-dimensional gel electrophoresis (2DE) analyses and mass spectroscopic identification of proteins with altered expression in mouse testes at different times after heat shock. We established a proteome reference map from 7-wk-old mouse testis linked to a federated proteome database. We used these tools to analyze quantitative variations in the tissue over a time course of 0.5, 2, 6, and 12 h following heat exposure. We separated 108 protein spots expressed differentially between the heat shock tissues and the control mouse testes. Of these spots, we identified 36 by comparing with the control reference map. We then focused on the heterogeneous nuclear ribonucleoproteins (hnRNPs) and the chaperonins containing t-complex polypeptide-1 (CCT). Further analysis in this heat-shocked model suggests numerous potential mechanisms for heat shock-induced spermatogenic disorder.  相似文献   
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