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91.
92.
93.
Beta‐diversity metrics of the upper digestive tract microbiome are associated with body mass index
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94.
Laura Eichelberger Gwen Murphy Arash Etemadi Christian C. Abnet Farhad Islami Ramin Shakeri Reza Malekzadeh Sanford M. Dawsey 《PloS one》2015,10(5)
Background
Gastric cancer (GC) is the world’s fifth most common cancer, and the third leading cause of cancer-related death. Over 70% of incident cases and deaths occur in developing countries. We explored whether disparities in access to improved drinking water sources were associated with GC risk in the Golestan Gastric Cancer Case Control Study.Methods and Findings
306 cases and 605 controls were matched on age, gender, and place of residence. We conducted unconditional logistic regression to calculate odds ratios (ORs) and 95% confidence intervals (CI), adjusted for age, gender, ethnicity, marital status, education, head of household education, place of birth and residence, homeownership, home size, wealth score, vegetable consumption, and H. pylori seropositivity. Fully-adjusted ORs were 0.23 (95% CI: 0.05–1.04) for chlorinated well water, 4.58 (95% CI: 2.07–10.16) for unchlorinated well water, 4.26 (95% CI: 1.81–10.04) for surface water, 1.11 (95% CI: 0.61–2.03) for water from cisterns, and 1.79 (95% CI: 1.20–2.69) for all unpiped sources, compared to in-home piped water. Comparing unchlorinated water to chlorinated water, we found over a two-fold increased GC risk (OR 2.37, 95% CI: 1.56–3.61).Conclusions
Unpiped and unchlorinated drinking water sources, particularly wells and surface water, were significantly associated with the risk of GC. 相似文献95.
We present MassSieve, a Java‐based platform for visualization and parsimony analysis of single and comparative LC‐MS/MS database search engine results. The success of mass spectrometric peptide sequence assignment algorithms has led to the need for a tool to merge and evaluate the increasing data set sizes that result from LC‐MS/MS‐based shotgun proteomic experiments. MassSieve supports reports from multiple search engines with differing search characteristics, which can increase peptide sequence coverage and/or identify conflicting or ambiguous spectral assignments. 相似文献
96.
Perez J Eigenbrode SD Hilje L Tripepi RR Aguilar ME Mesen F 《Neotropical Entomology》2010,39(4):618-625
The susceptible species Cedrela odorata and Swietenia macrophylla to attack by Hypsipyla grandella (Zeller) larvae were grafted onto the resistant species Khaya senegalensis and Toona ciliata. Six-month-old grafted plants were then compared to their reciprocal grafts and to both intact (non-grafted) and autografted plants for damage due to H. grandella larvae and for their effects on larval performance. Two experiments were conducted: one in which the apical bud of the main plant shoot was inoculated with H. grandella eggs, and the other in which the bud was inoculated with third instars. Damage in each experiment was assessed by the number of frass piles, number and length of tunnels, number of damaged leaves, and damage to the apical bud. Larval performance was evaluated in terms of time to reach pupation and pupal weight and length. In both experiments, plant damage differed significantly among treatments (P < 0.03). Resistant rootstocks conferred resistance to susceptible scions. In both experiments, grafting by itself, regardless of the rootstock and scion combination, also reduced damage caused by H. grandella larvae. Scions of autografted susceptible species had similar resistance to susceptible scions grafted on resistant rootstocks. Few larvae reached pupation, and their pupal weight and length were similar. 相似文献
97.
Allomermis solenopsi n. sp. (Mermithidae: Nematoda) is described from the fire ant Solenopsis invicta Buren (Hymenoptera: Formicidae) in Argentina. Diagnostic characters of the new species include stiff and erect processes on the surface of the mature egg, small female amphids, extension of the latero-medial rows of male genital papillae beyond the middle rows, an obliquely truncate spicule tip and a ventrally swollen male terminus. This is the first record of Allomermis Steiner, 1924 from South America and the first host record for members of this genus. Previous records of mermithids from Solenopsis spp. are summarised. The placement in Allomermis was confirmed by molecular analyses based on nuclear 18S ribosomal DNA sequences, the first such molecular framework for the Mermithidae. The possible life-cycle of the parasite is discussed, with the aim of using A. solenopsi as a biological control agent for fire ants in the United States. 相似文献
98.
Valles SM Strong CA Oi DH Porter SD Pereira RM Vander Meer RK Hashimoto Y Hooper-Bùi LM Sánchez-Arroyo H Davis T Karpakakunjaram V Vail KM Fudd Graham LC Briano JA Calcaterra LA Gilbert LE Ward R Ward K Oliver JB Taniguchi G Thompson DC 《Journal of invertebrate pathology》2007,96(1):18-27
Studies were conducted to examine the phenology, geographic distribution, and host specificity of the Solenopsis invicta virus-1 (SINV-1). Two genotypes examined, SINV-1 and -1A, exhibited similar seasonal prevalence patterns. Infection rates among colonies of S. invicta in Gainesville, Florida, were lowest from early winter (December) to early spring (April) increasing rapidly in late spring (May) and remaining high through August before declining again in the fall (September/October). Correlation analysis revealed a significant relationship between mean monthly temperature and SINV-1 (p<0.0005, r=0.82) and SINV-1A (p<0.0001, r=0.86) infection rates in S. invicta colonies. SINV-1 was widely distributed among S. invicta populations. The virus was detected in S. invicta from Argentina and from all U.S. states examined, with the exception of New Mexico. SINV-1 and -1A were also detected in other Solenopsis species. SINV-1 was detected in Solenopsis richteri and the S. invicta/richteri hybrid collected from northern Alabama and Solenopsis geminata from Florida. SINV-1A was detected in S. geminata and Solenopsis carolinensis in Florida and the S. invicta/richteri hybrid in Alabama. Of the 1989 arthropods collected from 6 pitfall trap experiments from Gainesville and Williston, Florida, none except S. invicta tested positive for SINV-1 or SINV-1A. SINV-1 did not appear to infect or replicate within Sf9 or Dm-2 cells in vitro. The number of SINV-1 genome copies did not significantly increase over the course of the experiment, nor were any cytopathic effects observed. Phylogenetic analyses of SINV-1/-1A nucleotide sequences indicated significant divergence between viruses collected from Argentina and the U.S. 相似文献
99.
Syk, c-Src, the alphavbeta3 integrin, and ITAM immunoreceptors, in concert, regulate osteoclastic bone resorption
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Zou W Kitaura H Reeve J Long F Tybulewicz VL Shattil SJ Ginsberg MH Ross FP Teitelbaum SL 《The Journal of cell biology》2007,176(6):877-888
In this study, we establish that the tyrosine kinase Syk is essential for osteoclast function in vitro and in vivo. Syk−/− osteoclasts fail to organize their cytoskeleton, and, as such, their bone-resorptive capacity is arrested. This defect results in increased skeletal mass in Syk−/− embryos and dampened basal and stimulated bone resorption in chimeric mice whose osteoclasts lack the kinase. The skeletal impact of Syk deficiency reflects diminished activity of the mature osteoclast and not impaired differentiation. Syk regulates bone resorption by its inclusion with the αvβ3 integrin and c-Src in a signaling complex, which is generated only when αvβ3 is activated. Upon integrin occupancy, c-Src phosphorylates Syk. αvβ3-induced phosphorylation of Syk and the latter's capacity to associate with c-Src is mediated by the immunoreceptor tyrosine-based activation motif (ITAM) proteins Dap12 and FcRγ. Thus, in conjunction with ITAM-bearing proteins, Syk, c-Src, and αvβ3 represent an essential signaling complex in the bone-resorbing osteoclast, and, therefore, each is a candidate therapeutic target. 相似文献
100.
Clonogenic assay is a widely used experimental approach to test for the effects of drugs/genes on the growth and proliferative
characteristics of cells in vitro. Accurate quantitation of treatment effects in clonogeneic assays depends on the ability
to visualize and count cell colonies precisely. We report a novel method (referred as ETeB) for staining cell colonies grown
on plastic and specially coated substrates like collagen. Using colon cancer cell lines grown on plastic and collagen, we
compared the colony staining efficiencies of the widely used methylene blue, and Ethidium bromide (ETeB) stains. Results show
that the ETeB protocol works well on plastic and is extremely effective for staining colonies on collagen when compared to
methylene blue. The key features and advantages of ETeB technique are; (a) reduction in background for colonies grown on collagen
and possibly other substrates, (b) the whole procedure takes less than a minute, (c) no post-stain washing step is required
which eliminates colony losses for cell lines that are loosely adherent, (d) colony visualization and counting can be done
immediately following the staining procedure using a standard UV illuminator and software, and (e) the method works across
a wide variety of cell lines. The simplicity and robustness of this procedure should warrant its usage in both small and large-scale
clonogenic experiments.
相似文献
Kishore GudaEmail: |