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991.
Charles R. Bursey Stephen R. Goldberg Fred Kraus 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2007,52(2):142-145
Falcaustra papuensis sp. nov. (Ascaridida, Kathlaniidae) from the large intestine of Sphenomorphus simus (Squamata, Sciencidae) is described and illustrated. Falcaustra papuensis represents the 4th Australo-Papuan species assigned to this genus and is distinguished from other Australo-Papuan species
by the distribution pattern of caudal papillae (6 precloacal, 6 adcloacal, 8 postcloacal, and 1 median), length of spicules
(561–714 μm) and presence of a pseudosucker. Sphenomorphus simus was found to harbor 2 additional species of nematodes, Meteterakis crombiei and Oswaldocruzia bakeri. Sphenomorphus simus represents a new host record for each of these nematode species. 相似文献
992.
Anthony J Sharp Paul E Polak Vittoria Simonini Shao X Lin Jill C Richardson Ernesto R Bongarzone Douglas L Feinstein 《Journal of neuroinflammation》2008,5(1):33
Background
The purinergic receptor P2x7 is expressed on myeloid cells as well as on CNS glial cells, and P2x7 activation has been shown to increase both glial and T-cell activation. These properties suggest a role in the development of autoimmune disease including multiple sclerosis. 相似文献993.
Woodward MJ Best A Sprigings KA Pearson GR Skuse AM Wales A Hayes CM Roe JM Low JC La Ragione RM 《International journal of medical microbiology : IJMM》2003,293(4):299-308
Ruminants are regarded as a primary reservoir for Escherichia coli O157:H7, an important human pathogen. Intimin, encoded by the Locus of Enterocyte Effacement by E. coli O157:H7 organisms, has been cited as one bacterial mechanism of colonisation of the gastrointestinal tract. To confirm this and to test whether a non-toxigenic E. coli O157:H7 strain would colonise and persist in a sheep model, E. coli O157:H7 strain NCTC12900, that lacks Shiga toxin (stx) genes, was evaluated for use in a sheep model of persistence. Following oral inoculation of six-week-old sheep, persistent excretion of NCTC12900 was observed for up to 48 days. E. coli O157-associated attaching-effacing (AE) lesions were detected in the caecum and rectum of one six-week-old lamb, one day after inoculation. This is the first recorded observation of AE lesions in orally inoculated weaned sheep. Also, mean faecal excretion scores of NCTC12900 and an isogenic intimin (eae)-deficient mutant were determined from twenty-four six-week-old orally inoculated sheep. The eae mutant was cleared within 20 days and had lower mean excretion scores at all time points after day one post inoculation compared with the parental strain that was still being excreted at 48 days. Tissues were collected post mortem from animals selected at random from the study groups over the time course of the experiment. The eae mutant was detected in only 1/43 samples but the parental strain was recovered from 64/140 samples primarily from the large bowel although rumen, duodenum, jejunum, and ileum were culture positive especially from animals that were still excreting at and beyond 27 days after inoculation. 相似文献
994.
Martin DM Mindell MH Kwierant CA Glover TW Gorski JL 《American journal of medical genetics. Part A》2003,(3):268-271
Complex congenital heart defects (CHD) are associated with a variety of single gene abnormalities and chromosomal rearrangements. Of the various forms of CHD, aortic arch interruption, a conotruncal heart defect, is relatively uncommon. Here we report a male neonate with aortic arch interruption type B, secundum atrial septal defect, perimembranous ventricular septal defect, patent ductus arteriosus, aortic and subaortic stenosis, and trisomy 5q31.1q35.1 resulting from a maternal balanced insertion (20;5). Chromosomal deletions, including deletion 22q11, have been reported with interrupted aortic arch (IAA); however, to our knowledge this is the first report of a trisomy of distal chromosome 5q associated with aortic arch interruption. Here we compare this child's features to other cases of trisomy 5q31.1q35.1, and review other causes of IAA. We conclude that gene dosage in this chromosomal region likely influences aortic arch development. 相似文献
995.
Krezowski J Knudson D Ebeling C Pitstick R Giri RK Schenk D Westaway D Younkin L Younkin SG Ashe KH Carlson GA 《Human molecular genetics》2004,13(18):1989-1997
Phenotypes produced by expression of human amyloid precursor protein (APP) transgenes vary depending on the genetic background of the mouse. FVB/N mice overexpressing human APP695 develop a central nervous system disorder and die prematurely, precluding development of Abeta peptide amyloid plaques. 129S6 mice are resistant to the lethal effects of APP overexpression, allowing sufficient levels of Abeta expression for the development of amyloid plaques and age-dependent memory deficits. To identify the genes that determine susceptibility or resistance to APP we analyzed crosses involving FVB/NCr and 129S6.Tg2576 mice that overexpress 'Swedish' mutant (K670N, M671L) APP695. APP transgene-positive FVB129S6F1 (F1) mice are resistant to the lethal effects of APP overexpression, so FVBxF1 backcross and F2 intercross offspring were produced. Analysis of age of death as a quantitative trait revealed significant linkage to loci on proximal chromosome 14 and on chromosome 9; 129S6 alleles protect against the lethal effects of APP. Within the chromosome 14 interval are segments homologous to regions on human chromosome 10 that have been linked to late onset Alzheimer's disease or to levels of Abeta peptide in plasma. However, analysis of plasma Abeta peptide concentrations at 6 weeks in backcross offspring produced no significant linkage. Similarly, elevation of human Abeta peptide concentrations by expression of mutant presenilin transgenes did not increase the proportion of mice dying prematurely, suggesting that early death reflects effects of APP or fragments other than Abeta. 相似文献
996.
Optimization of computer software settings improves accuracy of pulsed-field gel electrophoresis macrorestriction fragment pattern analysis
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Duck WM Steward CD Banerjee SN McGowan JE Tenover FC 《Journal of clinical microbiology》2003,41(7):3035-3042
Computer-assisted analysis of pulsed-field gel electrophoresis (PFGE) libraries can facilitate comparisons of fragment patterns present on multiple gels. We evaluated the ability of the Advanced Analysis (version 4.01) and Database (version 1.12) modules of the Phoretix gel analysis software package (Nonlinear USA, Inc., Durham, N.C.) to accurately match DNA fragment patterns. Two gels containing 38 lanes of SmaI-digested Enterococcus faecalis OG1RF DNA were analyzed to assess the impact of (i) varying the lane position of the standards, (ii) using gel plugs made at different times, and (iii) normalizing the fragment patterns by using molecular weight (MW) algorithms versus retardation factor (R(f)) algorithms. Two sets of PFGE libraries (one containing SmaI restriction patterns from 62 Enterococcus faecium isolates and the other containing SmaI restriction patterns of 89 Staphylococcus aureus isolates) were analyzed to assess the impact of varying the matching tolerance algorithm (designated as the vector box setting [VBS]) in the Phoretix software. Varying the lane position of standards on a gel and using gel plugs made on different days resulted in different VBSs, although it was not possible to judge whether those differences were statistically significant. Normalization of E. faecalis OG1RF fragment patterns by R(f) and MW methodology yielded no statistically significant differences in variability between the same fragment on different lanes. Suboptimal VBSs decreased the specificity with which related isolates were grouped together in dendrograms. The optimal VBS for analysis of PFGE fragment patterns from E. faecalis isolates differed from that for S. aureus isolates and sometimes was not that recommended by the manufacturer. Thus, computer-assisted analysis of PFGE patterns seemed to compensate for the intra- and intergel variation evaluated in the present study, and optimizing the software for the species to be tested was a critical preliminary step before further PFGE library analysis. 相似文献
997.
Alicja Gryczyńska-Siemiątkowska Alicja Siedlecka Joanna Stańczak Miłosława Barkowska 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2007,52(2):165-170
Sand lizards (Lacerta agilis) were trapped and examined for ticks from May to September in 2002 and 2003 in Northeastern Poland. A total of 233 Ixodes ricinus (L.) ticks (76 larvae and 157 nymphs) was found on 31 of 235 captured lizards (13.2%). The tick infestation is relatively
low compared to that of mammals and passerine birds from the same area (Siński et al. 2006, Gryczyńska et al. 2002). Tick infestation depended on the month of capture, being the highest in spring. In autumn no ticks were recorded on
any of the captured lizards. The oldest lizards carried the highest number of ticks but no differences related to sex of the
host were found. All the collected ticks were analysed by PCR for the presence of Borrelia burgdorferi sensu lato, the etiological agents of Lyme disease. Spirochetes were detected in 11 out of 233 (4.7%) ticks tested. Genetic
analysis confirmed that the spirochetes are members of the Borrelia afzelii, B. garinii and B. burgdorferi sensu stricto genospecies. Mixed infection were not detected. The prevalence of infection was analysed in relation to months
of the capture, age and sex of the lizards, but differences were not statistically significant. The obtained results suggest
that lizards are probably not B. burgdorferi reservoirs, but further studies are required to confirm this. 相似文献
998.
Brian R Lawson Stanley M Belkowski John F Whitesides Paul Davis John W Lawson 《BMC complementary and alternative medicine》2007,7(1):20
Background
Rheumatoid arthritis (RA) and its accepted animal model, murine collagen-induced arthritis (CIA), are classic autoimmune inflammatory diseases which require proinflammatory cytokine production for pathogenesis. We and others have previously used N, N-dimethylglycine (DMG) and extracts from the New Zealand green-lipped mussel Perna canaliculus (Perna) as potent immunomodulators to modify ongoing immune and/or inflammatory responses. 相似文献999.
Objective: To evaluate which of 24 β-lactams used in susceptibility tests best discriminated between strains of Klebsiella pneumoniae and Escherichia coli that produce extended spectrum β-lactamases (ESBLs) from strains that produce older, more familiar, plasmid-mediated β-lactamases such as TEM-1 and SHV-1.
Methods: Susceptibility to the 24 β-lactam agents was determined by agar dilution and disk diffusion methodologies, using 27 strains of K. pneumoniae and E. coli that produced 22 different older plasmid-mediated β-lactamases and 28 strains that produced 17 different ESBLs.
Results: In general, strains that produced ESBLs were intermediate or resistant to cefpodoxime, whereas those that produced other β-lactamases were susceptible to this agent. The agar dilution test exhibited 96% sensitivity and 100% specificity in discriminating these two groups of organisms. The disk diffusion test exhibited 100% sensitivity and 96% specificity. All other β-lactam agents tested were inferior discriminators between the two groups of organisms.
Conclusions: Agar dilution and disk diffusion tests with cefpodoxime can be used to discriminate strains of K. pneumoniae and E. coli that produce ESBLs from those that produce older, plasmid-mediated β-lactamases. 相似文献
Methods: Susceptibility to the 24 β-lactam agents was determined by agar dilution and disk diffusion methodologies, using 27 strains of K. pneumoniae and E. coli that produced 22 different older plasmid-mediated β-lactamases and 28 strains that produced 17 different ESBLs.
Results: In general, strains that produced ESBLs were intermediate or resistant to cefpodoxime, whereas those that produced other β-lactamases were susceptible to this agent. The agar dilution test exhibited 96% sensitivity and 100% specificity in discriminating these two groups of organisms. The disk diffusion test exhibited 100% sensitivity and 96% specificity. All other β-lactam agents tested were inferior discriminators between the two groups of organisms.
Conclusions: Agar dilution and disk diffusion tests with cefpodoxime can be used to discriminate strains of K. pneumoniae and E. coli that produce ESBLs from those that produce older, plasmid-mediated β-lactamases. 相似文献
1000.
Patrick Tan 《BMC medicine》2008,6(1):27
Identifying the complete repertoire of genes and genetic variants that regulate the pathogenesis and progression of human
disease is a central goal of post-genomic biomedical research. In cancer, recent studies have shown that genome-wide association
studies can be successfully used to identify germline polymorphisms associated with an individual's susceptibility to malignancy.
In parallel to these reports, substantial work has also shown that patterns of somatic alterations in human tumors can be
successfully employed to predict disease prognosis and treatment response. A paper by Van Ness et al. published this month
in BMC Medicine reports the initial results of a multi-institutional consortium for multiple myeloma designed to evaluate the role of germline
polymorphisms in influencing multiple myeloma clinical outcome. Applying a custom-designed single nucleotide polymorphism
microarray to two separate patient cohorts, the investigators successfully identified specific combinations of germline polymorphisms
significantly associated with early clinical relapse. These results raise the exciting possibility that besides somatically
acquired alterations, germline genetic background may also exert an important influence on cancer patient prognosis and outcome.
Future 'personalized medicine' strategies for cancer may thus require incorporating genomic information from both tumor cells
and the non-malignant patient genome. 相似文献