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151.
Salmonellosis is one of the most common and widely distributed food borne diseases caused by Salmonella serovars. The emergence of multi drug resistant strains has become a threatening public health problem and targeting unique effectors of this pathogen can be considered as a powerful strategy for drug design. SalmonellaBase is an online web portal serving as an integrated source of information about Salmonella serovars with the data required for the structural and functional studies and the analysis of druggable targets in Salmonella. We have identified several target proteins, which helps in the pathogenicity of the organism and predicted their structures. The database will have the information on completely sequenced genomes of Salmonella species with the complete set of protein sequences of the respective strains, determined structures, predicted protein structures and biochemical pathways of the respective strains. In addition, we have provided information about name and source of the protein, Uniprot and Protein Data Bank codes and literature information. Furthermore, SalmonellaBase is linked to related databases and other resources. We have set up a web interface with different search and display options so that users have the ability to get the data in several ways. SalmonellaBase is a freely available database.

Availability

http://www.salmonellabase.com/  相似文献   
152.
Streptococcus iniae causes severe septicemia and meningitis in farmed fish and is also occasionally zoonotic. Vaccination against S. iniae is problematic, with frequent breakdown of protection in vaccinated fish. The major protective antigens in S. iniae are the polysaccharides of the capsule, which are essential for virulence. Capsular biosynthesis is driven and regulated by a 21-kb operon comprising up to 20 genes. In a long-term study, we have sequenced the capsular operon of strains that have been used in autogenous vaccines across Australia and compared it with the capsular operon sequences of strains subsequently isolated from infected vaccinated fish. Intriguingly, strains isolated from vaccinated fish that subsequently become infected have coding mutations that are confined to a limited number of genes in the cps operon, with the remainder of the genes in the operon remaining stable. Mutations in strains in diseased vaccinated fish occur in key genes in the capsular operon that are associated with polysaccharide configuration (cpsG) and with regulation of biosynthesis (cpsD and cpsE). This, along with high ratios of nonsynonymous to synonymous mutations within the cps genes, suggests that immune response directed predominantly against capsular polysaccharide may be driving evolution in a very specific set of genes in the operon. From these data, it may be possible to design a simple polyvalent vaccine with a greater operational life span than the current monovalent killed bacterins.  相似文献   
153.
Insulin receptors in the brain are found in high densities in the hippocampus, a region that is fundamentally involved in the acquisition, consolidation, and recollection of new information. Using the intranasal method, which effectively bypasses the blood-brain barrier to deliver and target insulin directly from the nose to the brain, a series of experiments involving healthy humans has shown that increased central nervous system (CNS) insulin action enhances learning and memory processes associated with the hippocampus. Since Alzheimer's disease (AD) is linked to CNS insulin resistance, decreased expression of insulin and insulin receptor genes and attenuated permeation of blood-borne insulin across the blood-brain barrier, impaired brain insulin signaling could partially account for the cognitive deficits associated with this disease. Considering that insulin mitigates hippocampal synapse vulnerability to amyloid beta and inhibits the phosphorylation of tau, pharmacological strategies bolstering brain insulin signaling, such as intranasal insulin, could have significant therapeutic potential to deter AD pathogenesis.  相似文献   
154.
Single nucleotide polymorphisms (SNPs) and haplotype alleles within the prion gene (PRNP) coding sequence of domestic sheep (Ovis aries) are associated with genetic predisposition to scrapie, a transmissible spongiform encephalopathy disease of sheep. This report describes regions of linkage disequilibrium (LD) throughout the PRNP gene region in U.S. sheep and provides a genetic framework for identifying additional PRNP determinants associated with scrapie resistance. Four sequence tagged sites (i.e., STS or amplicons) totaling 3869 bp and spanning 20 kbp of genomic PRNP sequence were sequenced in a diverse panel of 90 sires representing ten popular U.S. breeds of sheep. Analysis of these sequences identified 36 previously unreported polymorphisms. In combination with two previously characterized STS, 62 polymorphisms were analyzed in a 20-kbp PRNP region in this panel of U.S. sheep. Two regions of strong LD and ten common haplotypes were identified. The haplotype encoding amino acid residues A, R, and Q at codons 136, 154, and 171, respectively, was observed on nine larger haplotypes spanning PRNP from the promoter region to the 3′ untranslated region. The haplotype encoding VRQ was observed on two larger haplotypes, whereas ARR, ARH, and AHQ were each present on a single haplotype. The existence of multiple haplotypes encoding ARQ raises the question of whether sheep bearing these different haplotypes are equally susceptible to scrapie. The haplotype structure within the 20-kbp region of PRNP identified in this study is important for higher-resolution analysis of genetics contributions to scrapie susceptibility. Nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under the accession number DQ077504.  相似文献   
155.
156.
Avian vocal duets occur when paired birds produce temporally and structurally coordinated vocalizations. Duets are given by members of many species from taxonomically distinct lineages and show great variety in form that often reflects function. By describing the structure of vocal duets we can learn about the diversity of communication signals present in nature and also gain insight into the evolution and operation of those signals. This study quantified the usage patterns and acoustic structure of California towhee duet vocalizations, and tested the distinctiveness of duets among different pairs. California towhee duets consist of a 'squeal' vocalization that is highly unlike the species-typical call note or male advertizement song. California towhees duet an average of three times per hour during the breeding season, and all duets are accompanied by an approach response that brings duetting partners into close spatial proximity. Males and females produce duet contributions with the same syllabic structure. Individual birds produce highly variable squeal vocalizations that are distinctive enough to signal identity. California towhee duet characteristics indicate that the squeal vocalization has evolved separately from other vocal traits in this species and was promoted by natural selection as a duet-specific vocalization. Duet usage patterns and structure suggest that these communication signals function in a cooperative context.  相似文献   
157.
Summary  Two new combinations, one new and one resurrected name in Plectranthus L’Hér. are provided for species formerly placed in Leocus A. Chev.; conservation assessments are made for five species.  相似文献   
158.

Background

Sensing of muramyl dipeptide (MDP) is impaired in Crohn''s disease (CD) patients with disease-linked variants of the CARD15 (caspase activation and recruitment domain 15) gene. Animal studies suggest that normal CARD15 signalling prevents inflammatory bowel disease, and may be important for disease development in CD. However, only a small fraction of CD patients carry the disease linked CARD15 variants. The aim of this study was thus to investigate if changes could be found in CARD15 signalling in patients without disease associated CARD15 variants.

Methodology/Principal Findings

By mapping the response to MDP in peripheral monocytes obtained from CD patients in remission not receiving immunosuppresives, an impaired response to MDP was found in patients without disease linked CARD15 variants compared to control monocytes. This impairment was accompanied by a decreased activation of IκB kinase α/β (IKKα/β), the initial step in the nuclear factor κB (NFκB) pathway, whereas activation of mitogen-activated protein (MAP)-kinases was unaffected. MDP additionally stimulates the inflammasome which is of importance for processing of cytokines. The inflammasome was constitutively activated in CD, but unresponsive to MDP both in CD and control monocytes.

Conclusions/Significance

These results suggest that inhibited MDP-dependent pathways in CD patients not carrying the disease-associated CARD15 variants might be of importance for the pathogenesis of CD. The results reveal a dysfunctional immune response in CD patients, not able to sense relevant stimuli on the one hand, and on the other hand possessing constitutively active cytokine processing.  相似文献   
159.
Attractiveness judgments are thought to underpin adaptive mate choice decisions. We investigated how these judgments change during adolescence when mate choice is becoming relevant. Adolescents aged 11–15 evaluated faces and voices manipulated along dimensions that affect adults' judgments of attractiveness and that are thought to cue mate value. Facial stimuli consisted of pairs of faces that were more or less average, more or less feminine, or more or less symmetric. The adolescents selected the more average, symmetric, and feminine faces as more attractive more often than chance, but judgments of some facial traits differed significantly with rater age and sex, indicating a role of development in judgments of facial cues. Vocal stimuli consisted of pairs of voices manipulated to raise or lower perceived pitch. The older but not younger girls selected the lower-pitched male voices as more attractive at rates above chance, while the younger but not older boys selected the higher-pitched female voices as more attractive. Controlling for rater age, increased pubertal development was associated with increased selection of lower-pitched boys' voices by girls and decreased selection of feminized male faces by boys. Our results are the first to demonstrate that adolescents show somewhat similar attractiveness judgments to adults in age-matched stimuli and that age, sex, and pubertal development have measurable effects on adolescents' attractiveness judgments. They suggest that attractiveness judgments in humans, at least for some traits, are facultatively calibrated to the individual's life stage, only reaching adult values upon sexual maturity when mate choice decisions become relevant.  相似文献   
160.
Recent numerical studies of abdominal aortic aneurysm (AAA) suggest that intraluminal thrombus (ILT) may reduce the stress loading on the aneurysmal wall. Detailed fluid structure interaction (FSI) in the presence and absence of ILT may help predict AAA rupture risk better. Two patients, with varied AAA geometries and ILT structures, were studied and compared in detail. The patient specific 3D geometries were reconstructed from CT scans, and uncoupled FSI approach was applied. Complex flow trajectories within the AAA lumen indicated a viable mechanism for the formation and growth of the ILT. The resulting magnitude and location of the peak wall stresses was dependent on the shape of the AAA, and the ILT appeared to reduce wall stresses for both patients. Accordingly, the inclusion of ILT in stress analysis of AAA is of importance and would likely increase the accuracy of predicting AAA risk of rupture.  相似文献   
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