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151.
The throat is an ecological assemblage involved human cells and microbiota, and the colonizing bacteria are important factors in balancing this environment. However, this bacterial community profile has thus been poorly investigated. The purpose of this study was to investigate the microbial biology of the larynx and to analyze the throat biodiversity in laryngeal carcinoma patients compared to a control population in a case-control study. Barcoded pyrosequencing analysis of the 16S rRNA gene was used. We collected tissue samples from 29 patients with laryngeal carcinoma and 31 control patients with vocal cord polyps. The findings of high-quality sequence datasets revealed 218 genera from 13 phyla in the laryngeal mucosa. The predominant communities of phyla in the larynx were Firmicutes (54%), Fusobacteria (17%), Bacteroidetes (15%), Proteobacteria (11%), and Actinobacteria (3%). The leading genera were Streptococcus (36%), Fusobacterium (15%), Prevotella (12%), Neisseria (6%), and Gemella (4%). The throat bacterial compositions were highly different between laryngeal carcinoma subjects and control population (p = 0.006). The abundance of the 26 genera was significantly different between the laryngeal cancer and control groups by metastats analysis (p<0.05). Fifteen genera may be associated with laryngeal carcinoma by partial least squares discriminant analysis (p<0.001). In summary, this study revealed the microbiota profiles in laryngeal mucosa from tissue specimens. The compositions of bacteria community in throat were different between laryngeal cancer patients and controls, and probably were related with this carcinoma. The disruption of this bio-ecological niche might be a risk factor for laryngeal carcinoma.  相似文献   
152.
Osteoarthritis (OA) is a common joint disorder with varying degrees of inflammation. The ideal anti-OA drug should have immunomodulatory effects while at the same time having limited or no toxicity. We examined the anti-inflammatory effects of Ginkgo biloba extract (EGb) in interleukin-1 (IL-1)-stimulated human chondrocytes. Chondrocytes were prepared from cartilage specimens taken from patients with osteoarthritis who had received total hip or total knee replacement. The concentrations of chemokines and the degree of cell migration were determined by ELISA and chemotaxis assays, respectively. The activation of inducible nitric oxide synthase (iNOS), mitogen-activated protein kinases (MAPKs), activator protein-1 (AP-1), and nuclear factor-kappaB (NF-κB) was determined by immunoblotting, immunohistochemistry, and electrophoretic mobility shift assay. We found that EGb inhibited IL-1-induced production of chemokines, which in turn resulted in attenuation of THP-1 cell migration toward EGb-treated cell culture medium. EGb also suppressed IL-1-stimulated iNOS expression and release of nitric oxide (NO). The EGb-mediated suppression of the iNOS-NO pathway correlated with the attenuation of activator protein-1 (AP-1) but not nuclear factor-kappaB (NF-κB) DNA-binding activity. Of the mitogen-activated protein kinases (MAPKs), EGb inhibited only c-Jun N-terminal kinase (JNK). Unexpectedly, EGb selectively caused degradation of c-Jun protein. Further investigation revealed that EGb-mediated c-Jun degradation was preceded by ubiquitination of c-Jun and could be prevented by the proteosome inhibitor MG-132. The results imply that EGb protects against chondrocyte degeneration by inhibiting JNK activation and inducing ubiquitination-dependent c-Jun degradation. Although additional research is needed, our results suggest that EGb is a potential therapeutic agent for the treatment of OA.  相似文献   
153.
154.

Background

Dengue virus (DENV) is the most widespread arbovirus with an estimated 100 million infections occurring every year. Endemic in the tropical and subtropical areas of the world, dengue fever/dengue hemorrhagic fever (DF/DHF) is emerging as a major public health concern. The complex array of concurrent host physiologic changes has hampered a complete understanding of underlying molecular mechanisms of dengue pathogenesis.

Methodology/Principle Findings

Systems level characterization of serum metabolome and lipidome of adult DF patients at early febrile, defervescence, and convalescent stages of DENV infection was performed using liquid chromatography- and gas chromatography-mass spectrometry. The tractability of following metabolite and lipid changes in a relatively large sample size (n = 44) across three prominent infection stages allowed the identification of critical physiologic changes that coincided with the different stages. Sixty differential metabolites were identified in our metabolomics analysis and the main metabolite classes were free fatty acids, acylcarnitines, phospholipids, and amino acids. Major perturbed metabolic pathways included fatty acid biosynthesis and β-oxidation, phospholipid catabolism, steroid hormone pathway, etc., suggesting the multifactorial nature of human host responses. Analysis of phospholipids and sphingolipids verified the temporal trends and revealed association with lymphocytes and platelets numbers. These metabolites were significantly perturbed during the early stages, and normalized to control levels at convalescent stage, suggesting their potential utility as prognostic markers.

Conclusions/Significance

DENV infection causes temporally distinct serum metabolome and lipidome changes, and many of the differential metabolites are involved in acute inflammatory responses. Our global analyses revealed early anti-inflammatory responses working in concert to modulate early pro-inflammatory processes, thus preventing the host from development of pathologies by excessive or prolonged inflammation. This study is the first example of how an omic- approach can divulge the extensive, concurrent, and dynamic host responses elicited by DENV and offers plausible physiological insights to why DF is self limiting.  相似文献   
155.

Background

The recurrence of colorectal cancer (CRC) is frequent within the first year of curative resection surgery and may be unavoidable. microRNAs have been suggested to play roles in carcinogenesis and cancer recurrence. We recently identified microRNA-29c (miRNA-29c) as a predictor of early recurrence in CRC. In the present study, we further investigated the functions and serum level of miRNA-29c in relation to early recurrence of CRC.

Methods

First we further confirmed overexpression of miRNA-29c in non-early relapse subjects. Gain-of-function in vitro studies were used to evaluate the effect of miRNA-29c on cell proliferation, migration, invasion, and cell cycle progression. The colon cancer cell line Caco2 and a stable clone overexpressing miRNA-29c were xenografted to evaluate the in vivo effect of miRNA-29c in null mice. Finally, circulating miRNA-29c was investigated as a potential biomarker for identifying early relapse.

Results

miRNA-29c expression significantly decreased during early relapse compared to non-early relapse in UICC stage II and III CRC patients (P = 0.021). In vitro studies showed that overexpression of miRNA-29c inhibited cell proliferation and migration. The cell cycle studies also revealed that miRNA-29c caused an accumulation of the G1 and G2 population. In vivo, miRNA-29c suppressed tumor growth in null mice. The serum miRNA-29c increased significantly in early relapsed patients compared to non-early elapsed patients (P = 0.012).

Conclusions

miRNA-29c shows anti-tumorigenesis activity, and preoperative circulating miRNA-29c levels can be used to predict postoperative early relapse of CRC.  相似文献   
156.

Background

Pre-eclampsia is the leading cause of maternal and neonatal morbidity and mortality with incompletely understood etiopathogenesis. The purpose of the current study is to determine whether there is a relationship between the presence of autoantibodies against β1, β2 and α1 adrenoreceptors and severe pre-eclampsia.

Methodology/Principal Findings

Synthetic peptides corresponding to amino acid sequences of the second extracellular loops of β1, β2 and α1 adrenoreceptors were synthesized as antigens to test 34 patients with severe pre-eclampsia, 36 normal pregnancy women and 40 non-pregnant controls for the presence of autoantibodies using enzyme-linked immunosorbent assay. The respective frequencies of autoantibodies against β1, β2 and α1 adrenoreceptors were 50.0% (17/34), 52.9% (18/34) and 55.9% (19/34) in patients with severe pre-eclampsia, 19.4% (7/36) (p = 0.011), 19.4% (7/36) (p = 0.006) and 17.6% (6/36) (p = 0.001) in normal pregnancy women and 10% (4/40), 7.5% (3/40) and 10% (4/40) (p<0.001) in non-pregnant controls. Titers of these autoantibodies were also significantly increased in patients with severe pre-eclampsia. By logistic regression analysis, the presence of these three autoantibodies significantly increased the risk of neonatal death (odds ratio, 13.5; 95% confidence interval, 1.3–141.3; p = 0.030) and long-term neonatal hospitalization (odds ratio, 5.0; 95% confidence interval, 1.3–19.1; p = 0.018). The risk of hypertension and fetal distress were also associated with the presence of these three autoantibodies.

Conclusions/Significance

This novel pilot study demonstrated for the first time that the presence of autoantibodies against β1, β2 and α1 adrenoreceptors are increased in patients with severe pre-eclampsia. Pregnant women who are positive for the three autoantibodies are at increased risks of neonatal mortality and morbidity. We posit that these autoantibodies may be involved in the pathogenesis of severe pre-eclampsia.  相似文献   
157.
Strontium (Sr) can promote the process of bone formation. To improve bioactivity, porous allograft bone scaffolds (ABS) were doped with Sr and the mechanical strength and bioactivity of the scaffolds were evaluated. Sr-doped ABS were prepared using the ion exchange method. The density and distribution of Sr in bone scaffolds were investigated by inductively coupled plasma optical emission spectrometry (ICP-OES), X-ray photoelectron spectroscopy (XPS), and energy-dispersive X-ray spectroscopy (EDS). Controlled release of strontium ions was measured and mechanical strength was evaluated by a compressive strength test. The bioactivity of Sr-doped ABS was investigated by a simulated body fluid (SBF) assay, cytotoxicity testing, and an in vivo implantation experiment. The Sr molar concentration [Sr/(Sr+Ca)] in ABS surpassed 5% and Sr was distributed nearly evenly. XPS analyses suggest that Sr combined with oxygen and carbonate radicals. Released Sr ions were detected in the immersion solution at higher concentration than calcium ions until day 30. The compressive strength of the Sr-doped ABS did not change significantly. The bioactivity of Sr-doped material, as measured by the in vitro SBF immersion method, was superior to that of the Sr-free freeze-dried bone and the Sr-doped material did not show cytotoxicity compared with Sr-free culture medium. The rate of bone mineral deposition for Sr-doped ABS was faster than that of the control at 4 weeks (3.28±0.23 µm/day vs. 2.60±0.20 µm/day; p<0.05). Sr can be evenly doped into porous ABS at relevant concentrations to create highly active bone substitutes.  相似文献   
158.
Hip (HD) and Elbow Dysplasia (ED) are two common complex developmental disorders of dogs. In order to decrease their prevalence and severity, the Orthopedic Foundation for Animals (OFA) has a voluntary registry of canine hip and elbow conformation certified by boarded radiologists. However, the voluntarily reports have been severely biased against exposing dogs with problems, especially at beginning period. Fluctuated by additional influential factors such as age, the published raw scores barely showed trends of improvement. In this study, we used multiple-trait mixed model to simultaneously adjust these factors and incorporate pedigree to derive Estimated Breeding Values (EBV). A total of 1,264,422 dogs from 74 breeds were evaluated for EBVs from 760,455 hip scores and 135,409 elbow scores. These EBVs have substantially recovered the reporting bias and the other influences. Clear and steady trends of genetic improvement were observed over the 40 years since 1970. The total genetic improvements were 16.4% and 1.1% of the phenotypic standard deviation for HD and ED, respectively. The incidences of dysplasia were 0.83% and 2.08%, and the heritabilities were estimated as 0.22 and 0.17 for hip and elbow scores, respectively. The genetic correlation between them was 0.12. We conclude that EBV is more effective than reporting raw phenotype. The weak genetic correlation suggested that selection based on hip scores would also slightly improve elbow scores but it is necessary to allocate effort toward improvement of elbow scores alone.  相似文献   
159.
NHERF1 is a PDZ adaptor protein that scaffolds the assembly of diverse signaling complexes and has been implicated in many cancers. However, little is known about the mechanism responsible for its scaffolding promiscuity or its ability to bind to multiple targets. Computational studies have indicated that PDZ promiscuity may be attributed to its conformational dynamics, but experimental evidence for this relationship remains very limited. Here we examine the conformational flexibility of the NHERF1 PDZ1 domain using crystal lattice trapping via solving PDZ1 structure of a new crystal form. The structure, together with prior PDZ1 structures of a different space group, reveals that 4 of 11 ligand-interacting residues undergo significant crystal packing-induced structural changes. Most of these residues correspond to the residues involved in allosteric transition when a peptide ligand binds. In addition, a subtle difference in ligand conformations causes the same peptide to bind in slightly different modes in different crystal forms. These findings indicate that substantial structural flexibility is present in the PDZ1 peptide-binding pocket, and the structural substate trapped in the present crystal form can be utilized to represent the conformational space accessible to the protein. Such knowledge will be critical for drug design against the NHERF1 PDZ1 domain, highlighting the continued need for experimentally determined PDZ1-ligand complexes.  相似文献   
160.
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