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81.
The revision of the Afrotropical Ophioninae is updated, based on the examination of about 800–900 individuals in the South African and European museum collections. A robust interactive matrix key was built to provide quick and reliable identifications. The key is available online at http://www.waspweb.org. Two new species are described: Dicamptus maxipol sp. n. and Enicospilus gauldetmitchellorum sp. n. Numerous new distribution and biological records are provided, and noticeable morphological intra-specific variations are detailed. Enicospilus batus Gauld & Mitchell, syn. n. is considered as a junior synonym of Enicospilus luebberti (Enderlein).  相似文献   
82.

Background

To determine which changes in the host cell genome are crucial for cervical carcinogenesis, a longitudinal in vitro model system of HPV-transformed keratinocytes was profiled in a genome-wide manner. Four cell lines affected with either HPV16 or HPV18 were assayed at 8 sequential time points for gene expression (mRNA) and gene copy number (DNA) using high-resolution microarrays. Available methods for temporal differential expression analysis are not designed for integrative genomic studies.

Results

Here, we present a method that allows for the identification of differential gene expression associated with DNA copy number changes over time. The temporal variation in gene expression is described by a generalized linear mixed model employing low-rank thin-plate splines. Model parameters are estimated with an empirical Bayes procedure, which exploits integrated nested Laplace approximation for fast computation. Iteratively, posteriors of hyperparameters and model parameters are estimated. The empirical Bayes procedure shrinks multiple dispersion-related parameters. Shrinkage leads to more stable estimates of the model parameters, better control of false positives and improvement of reproducibility. In addition, to make estimates of the DNA copy number more stable, model parameters are also estimated in a multivariate way using triplets of features, imposing a spatial prior for the copy number effect.

Conclusion

With the proposed method for analysis of time-course multilevel molecular data, more profound insight may be gained through the identification of temporal differential expression induced by DNA copy number abnormalities. In particular, in the analysis of an integrative oncogenomics study with a time-course set-up our method finds genes previously reported to be involved in cervical carcinogenesis. Furthermore, the proposed method yields improvements in sensitivity, specificity and reproducibility compared to existing methods. Finally, the proposed method is able to handle count (RNAseq) data from time course experiments as is shown on a real data set.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2105-15-327) contains supplementary material, which is available to authorized users.  相似文献   
83.
The genome of Mycobacterium tuberculosis (H37Rv) contains 4,019 protein coding genes, of which more than thousand have been categorized as 'hypothetical' implying that for these not even weak functional associations could be identified so far. We here predict reliable functional indications for half of this large hypothetical orfeome: 497 genes can be annotated based on orthology, and another 125 can be linked to interacting proteins via integrated genomic context analysis and literature mining. The assignments include newly identified clusters of interacting proteins, hypothetical genes that are associated to well known pathways and putative disease-relevant targets. All together, we have raised the fraction of the proteome with at least some functional annotation to 88% which should considerably enhance the interpretation of large-scale experiments targeting this medically important organism.  相似文献   
84.
There is now compelling evidence that members of the family of small heat shock proteins (HSP) can be secreted by a variety of different types of cells. Secretion of small HSP may at times represent altruistic delivery of supporting and stabilizing factors from one cell to another. A probably more general effect of extracellular small HSP, however, is exerted by their ability to activate macrophages and macrophage-like cells. When doing so, small HSP induce an immune-regulatory state of activation, stimulating macrophages to suppress inflammation. For this reason, small HSP deserve consideration as broadly applicable therapeutic agents for inflammatory disorders. In one particular case, however, adaptive immune responses to the small HSP itself may subvert the protective quality of the innate immune response it triggers. This situation only applies to alpha B-crystallin, and is unique for humans as well. In this special case, local concentrations of alpha B-crystallin determine the balance between protective innate responses and destructive adaptive responses, the latter of which are held responsible for the development of multiple sclerosis lesions. This article is part of a Directed Issue entitled: Small HSPs in physiology and pathology.  相似文献   
85.
Quercetin 2,3-dioxygenase is a copper-containing enzyme that catalyzes the insertion of molecular oxygen into polyphenolic flavonols. Dioxygenation catalyzed by iron-containing enzymes has been studied extensively, but dioxygenases employing other metal cofactors are poorly understood. We determined the crystal structure of quercetin 2,3-dioxygenase at 1.6 A resolution. The enzyme forms homodimers, which are stabilized by an N-linked heptasaccharide at the dimer interface. The mononuclear type 2 copper center displays two distinct geometries: a distorted tetrahedral coordination, formed by His66, His68, His112, and a water molecule, and a distorted trigonal bipyramidal environment, which additionally comprises Glu73. Manual docking of the substrate quercetin into the active site showed that the different geometries of the copper site might be of catalytic importance.  相似文献   
86.

Background  

Classical bioconjugation strategies for generating antibody-functionalized nanoparticles are non-specific and typically result in heterogeneous compounds that can be compromised in activity. Expression systems based on self-cleavable intein domains allow the generation of recombinant proteins with a C-terminal thioester, providing a unique handle for site-specific conjugation using native chemical ligation (NCL). However, current methods to generate antibody fragments with C-terminal thioesters require cumbersome refolding procedures, effectively preventing application of NCL for antibody-mediated targeting and molecular imaging.  相似文献   
87.

Background

The CONSORT Statement provides recommendations for reporting randomized controlled trials. We assessed the extent to which leading medical journals that publish reports of randomized trials incorporate the CONSORT recommendations into their journal and editorial processes.

Methods

This article reports on two observational studies. Study 1: We examined the online version of 'Instructions to Authors' for 165 high impact factor medical journals and extracted all text mentioning the CONSORT Statement or CONSORT extension papers. Any mention of the International Committee of Medical Journal Editors (ICMJE) or clinical trial registration were also sought and extracted. Study 2: We surveyed the editor-in-chief, or editorial office, for each of the 165 journals about their journal's endorsement of CONSORT recommendations and its incorporation into their editorial and peer-review processes.

Results

Study 1: Thirty-eight percent (62/165) of journals mentioned the CONSORT Statement in their online 'Instructions to Authors'; of these 37% (23/62) stated this was a requirement, 63% (39/62) were less clear in their recommendations. Very few journals mentioned the CONSORT extension papers. Journals that referred to CONSORT were more likely to refer to ICMJE guidelines (RR 2.16; 95% CI 1.51 to 3.08) and clinical trial registration (RR 3.67; 95% CI 2.36 to 5.71) than those journals which did not. Study 2: Thirty-nine percent (64/165) of journals responded to the on-line survey, the majority were journal editors. Eighty-eight percent (50/57) of journals recommended authors comply with the CONSORT Statement; 62% (35/56) said they would require this. Forty-one percent (22/53) reported incorporating CONSORT into their peer-review process and 47% (25/53) into their editorial process. Eighty-one percent (47/58) reported including CONSORT in their 'Instructions to Authors' although there was some inconsistency when cross checking information on the journal's website. Sixty-nine percent (31/45) of journals recommended authors comply with the CONSORT extension for cluster trials, 60% (27/45) for harms and 42% (19/45) for non-inferiority and equivalence trials. Few journals mentioned these extensions in their 'Instructions to Authors'.

Conclusion

Journals should be more explicit in their recommendations and expectations of authors regarding the CONSORT Statement and related CONSORT extensions papers.  相似文献   
88.
Grass was field-dried to 3 different dry matter (DM) levels (200, 430 and 540 g/kg) and inoculated with 106–107 cfu/g of a Listeria monocytogenes strain sharing a phagovar occasionally involved in food-borne outbreaks of listeriosis. Formic acid (3 ml/kg) or lactic acid bacteria (8·105/g) with cellulolytic enzymes were applied only to forages with low and intermediate DM levels. Forages were ensiled in laboratory silos (1700 ml) and were stored at 25°C for 30 or 90 days. After 90 days of storage, L. monocytogenes could not be detected in any silo, except one with the high dry matter grass without additive. After 30 days of storage, between 102 and 106 cfu L. monocytogenes/g silage were isolated from the untreated silages. Increasing the DM content from 200 to 540 g/kg did not reduce listeria counts possibly because of the lower production of fermentation acids (higher pH). In silages treated with additives, counts of L. monocytogenes were always lower than in silages without additive. In wet silages (DM 200 g/kg) both additives were effective, but in the wilted silages (DM 430 g/kg) only the bacterial additive reduced listeria counts below detection level. Listeria counts were highly correlated to silage pH (r = 0.92), the concentration of lactic acid (r = -0.80) and the pooled amount of undissociated acids (r = -0.83).  相似文献   
89.
90.
When considering the interactions between bacteriophages and their host, the issue of phage-resistance emergence is a key element in understanding the ecological impact of phages on the bacterial population. It is also an essential parameter for the implementation of phage therapy to combat antibiotic-resistant pathogens. This study investigates the phenotypic and genetic responses of five Pseudomonas aeruginosa strains (PAO1, A5803, AA43, CHA, and PAK) to the infection by seven phages with distinct evolutionary backgrounds and recognised receptors (LPS/T4P). Emerging phage-insensitivity was generally accompanied by self and cross-resistance mechanisms. Significant differences were observed between the reference PAO1 responses compared to other clinical representatives. LPS-dependent phage infections in clinical strains selected for mutations in the “global regulatory” and “other” genes, rather than in the LPS-synthesis clusters detected in PAO1 clones. Reduced fitness, as proxied by the growth rate, was correlated with large deletion (20–500 kbp) and phage carrier state. Multi-phage resistance was significantly correlated with a reduced growth rate but only in the PAO1 population. In addition, we observed that the presence of prophages decreased the lytic phage maintenance seemingly protecting the host against carrier state and occasional lytic phage propagation, thus preventing a significant reduction in bacterial growth rate.Subject terms: Bacteriophages, Biodiversity  相似文献   
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