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101.
A large open reading frame (ORF) has been identified in two German cowpox virus strains. The ORFs (5676 and 5679 nt, respectively) differ in 10 nucleotides, resulting in an amino acid homology of 99.8%. In searching GenBank nucleotide sequences (>90% identity) were present in several small ORFs in variola major, variola minor and camelpox virus genomes. Alignments revealed that these small ORFs are fragments of a large ORF. However, sequences of the ORF described here are entirely absent in the two cowpox virus reference strains. Databank analysis revealed amino acid identities (ranging from 25 to 39%) with so-called B22R-like poxviral proteins with unknown function encoded by several chordopoxviruses. Further sequencing of one cowpox virus strain under study identified an ORF (5790 nt) which displays high levels of nucleotide identity to ORFs present in several orthopoxvirus species. Taken together, the two cowpox viruses analyzed here contain one large ORF which is conserved within the genus Orthopoxvirus and a unique, more distantly related ORF of similar size, which is conserved in the subfamily Chordopoxvirinae. 相似文献
102.
Rotavirus infection of cultured cells induces a progressive increase in plasma membrane permeability to Ca2+. The viral product responsible for this effect is not known. We have used tunicamycin and brefeldin A to prevent glycosylation and membrane traffic and study the involvement of viral glycoproteins, NSP4 and/or VP7, in rotavirus-infected HT29 and MA104 cells. In infected cells, we observed an increase of plasma membrane Ca2+ permeability and a progressive depletion of agonist-releasable ER pools measured with fura 2 and an enhancement of total Ca2+ content measured as 45Ca2+ uptake. Tunicamycin inhibited the increase in membrane Ca2+ permeability, induced a depletion of agonist-releasable and 45Ca2+-sequestered pools. Brefeldin A inhibited the increase of Ca2+ permeability and the increase in 45Ca2+ uptake induced by infection. We propose that the glycosylated viral product NSP4 (and/or VP7) travels to the plasma membrane to form a Ca2+ channel and hence elevate Ca2+ permeability. 相似文献
103.
Molecular epidemiology of sequential outbreaks of Acinetobacter baumannii in an intensive care unit shows the emergence of carbapenem resistance 总被引:15,自引:0,他引:15
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Zarrilli R Crispino M Bagattini M Barretta E Di Popolo A Triassi M Villari P 《Journal of clinical microbiology》2004,42(3):946-953
The molecular epidemiology of multidrug-resistant Acinetobacter baumannii was investigated in the medical-surgical intensive care unit (ICU) of a university hospital in Italy during two window periods in which two sequential A. baumannii epidemics occurred. Genotype analysis by pulsed-field gel electrophoresis (PFGE) of A. baumannii isolates from 131 patients identified nine distinct PFGE patterns. Of these, PFGE clones B and I predominated and occurred sequentially during the two epidemics. A. baumannii epidemic clones showed a multidrug-resistant antibiotype, being clone B resistant to all antimicrobials tested except the carbapenems and clone I resistant to all antimicrobials except ampicillin-sulbactam and gentamicin. Type 1 integrons of 2.5 and 2.2 kb were amplified from the chromosomal DNA of epidemic PFGE clones B and I, respectively, but not from the chromosomal DNA of the nonepidemic clones. Nucleotide analysis of clone B integron identified four gene cassettes: aacC1, which confers resistance to gentamicin; two open reading frames (ORFs) coding for unknown products; and aadA1a, which confers resistance to spectinomycin and streptomycin. The integron of clone I contained three gene cassettes: aacA4, which confers resistance to amikacin, netilmicin, and tobramycin; an unknown ORF; and bla(OXA-20), which codes for a class D beta-lactamase that confers resistance to amoxicillin, ticarcillin, oxacillin, and cloxacillin. Also, the bla(IMP) allele was amplified from chromosomal DNA of A. baumannii strains of PFGE type I. Class 1 integrons carrying antimicrobial resistance genes and bla(IMP) allele in A. baumannii epidemic strains correlated with the high use rates of broad-spectrum cephalosporins, carbapenems, and aminoglycosides in the ICU during the study period. 相似文献
104.
105.
Bellan C De Falco G Lazzi S Micheli P Vicidomini S Schürfeld K Amato T Palumbo A Bagella L Sabattini E Bartolommei S Hummel M Pileri S Tosi P Leoncini L Giordano A 《The Journal of pathology》2004,203(4):946-952
CDK9 is a member of the CDC2-like family of kinases. Its cyclin partners are members of the CYCLIN T family (T1, T2a, and T2b) and CYCLIN K. The CDK9/CYCLIN T1 complex is very important in the differentiation programme of several cell types, controlling specific differentiation pathways. Limited data are available regarding the expression of CDK9/CYCLIN T1 in haematopoietic and lymphoid tissues. The aim of this study was to analyse the expression of the CDK9/CYCLIN T1 complex in lymphoid tissue, in order to assess its role in B- and T-cell differentiation and lymphomagenesis. CDK9/CYCLIN T1 expression was found by immunohistochemistry in precursor B and T cells. In peripheral lymphoid tissues, germinal centre cells and scattered B- and T-cell blasts in interfollicular areas expressed CDK9/CYCLIN T1, while mantle cells, plasma cells, and small resting T-lymphocytes displayed no expression of either molecule. CDK9/CYCLIN T1 expression therefore appears to be related to particular stages of lymphoid differentiation/activation. CDK9 and CYCLIN T1 were highly expressed in lymphomas derived from precursor B and T cells, from germinal centre cells, such as follicular lymphomas, and from activated T cells (ie anaplastic large cell lymphomas). Hodgkin and Reed-Sternberg cells of classical Hodgkin's lymphoma also showed strong nuclear staining. Diffuse large B-cell, Burkitt's lymphomas, and peripheral T-cell lymphomas, among T-cell lymphoproliferative disorders, showed a wide range of values. No expression of CDK9 or CYCLIN T1 was detected in mantle cell and marginal zone lymphomas. However, at the mRNA level, an imbalance in the CDK9/CYCLIN T1 ratio was found in follicular lymphoma and diffuse large B-cell lymphomas with germinal centre phenotype, and in the cell lines of classical Hodgkin's lymphomas, Burkitt's lymphomas, and anaplastic large cell lymphoma, in comparison with reactive lymph nodes. These results suggest that the CDK9/CYCLIN T1 complex may affect the activation and differentiation programme of lymphoid cells. The molecular mechanism through which the CDK9/CYCLIN T1 complex is altered in malignant transformation needs to be elucidated. 相似文献
106.
The incidence of kidney disease in the United States is rising at a steady, alarming pace. The growth rate has been particularly rapid for end-stage renal disease (ESRD), which has been reported to double every 10 years. Of even greater concern is the emergence of striking racial disparities in the prevalence, morbidity, and mortality of kidney disease, and in the provision of optimal care to prevent or slow progression of the disease. Hispanics, who are among the fastest-growing racial groups in the United States, are twice as likely to develop kidney failure as non-Hispanic whites, largely due to the increased prevalence of diabetes mellitus in the Hispanic population. However, Hispanic patients are less likely than the general U.S. population to be screened for risk factors for kidney disease or receive optimal treatment after diagnosis. Several actions are required to redress these racial inequalities. Improved cultural sensitivity on the part of physicians is fundamentally important, as are patient education programs targeted specifically at the diverse Hispanic groups. In addition, local initiatives should be supported on a wider scale by healthcare policymakers to encourage improved medical care within Hispanic communities and thereby reduce the burden of kidney disease on American society as a whole. 相似文献
107.
The effect of yoghurt on the cytotoxic and phagocytic activity of macrophages in tumour‐bearing mice
Juan Carlos Valdez Mirta Rachid Elena Bru Gabriela Perdigón 《Food and Agricultural Immunology》1997,9(4):299-308
In a previous paper, it was demonstrated that feeding yoghurt was able to inhibit the growth of an intestinal tumour induced chemically with 1,2‐dimethylhydrazine (DMH). This effect was due to the increase in IgA‐producing cells and a diminution of the inflammatory immune response. In this paper the phagocytic and cytotoxic capacity of macrophages both involved and not involved in the target organ are studied. The study was aimed at determining whether in the intestinal tumour inhibition demonstrated previously the systemic immune response was also increased. The cytotoxic capacity and ß‐glucuronidase enzyme levels of the peritoneal macrophages were analyzed together with the cytolytic effect of the serum on tumour cells and the phagocytic activity of the macrophages infiltrating the intestinal mucosa. Groups of mice were split into three experimental groups. One group was treated with DMH. The others were treated with DMH, and their diets were supplemented with yoghurt for 7 or 10 consecutive days, during 24 weeks. It was demonstrated that feeding yoghurt for 7 or 10 days increased cytotoxic and ß‐glucuronidase levels in peritoneal macrophages, and also the cytolytic capacity of serum, reaching values significantly higher than those in the DMH control. Enhancement of the phagocytic activity of the macrophages associated with the large intestine was also observed. This increase in the macrophage activity involved in the systemic and mucosal immune responses could also be responsible for the tumour inhibition observed in the group of mice fed with yoghurt. The presence in the serum of lytic factors (cytokines) which were released by immune cells activated by feeding yoghurt may also have had a role in tumour inhibition. 相似文献
108.
Vicente AC Agwale SM Otsuki K Njouku OM Jelpe D Idoko JA Caride E Brindeiro RM Tanuri A 《Virus genes》2001,22(2):181-186
In Nigeria, the most populous country in Africa, the characterization of HIV-1 strains has been limited. In this study we evaluated the genetic diversity of the protease coding region, one of the anti-retroviral therapy target, and investigated the presence of mutations related to resistance to HIV protease inhibitors. We analyzed samples collected during 1996 and all patients were anti-retroviral drug na¨ves. Ten samples were evaluated by sequencing of the protease gene. The majority, 80%, were classified as subtype A and the two others were unclassified-divergent strains, something in between A and G subtypes. The gag region from these outliners were sequenced and the phylogenetic analysis classified them as subtype G. The protease amino acid consensus sequence of the Nigerian subtype A are in complete agreement with the consensus A differing from the USA subtype B consensus in 10 positions (L10V, I13V, K14R, I15V, K20I, M36I, R41K, P63L, H69K and L89M).The secondary substitutions associated with protease inhibitor resistance were observed in all Nigerian sequences at the positions L10V, M36I and L89M. The majority of sequence variation was concentrated in the interval between aminoacids 70–90 where the protease substrate binding region is located. 相似文献
109.
Francesca Blasi Elena Bacchelli Giulia Pesaresi Simona Carone Anthony J Bailey Elena Maestrini 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2006,(3):220-221
Neuroligin abnormalities have been recently implicated in the aetiology of autism spectrum disorders (ASD), given the finding of point mutations in the two X-linked genes NLGN3 and NLGN4X and the important role of neuroligins in synaptogenesis. To enquire on the relevance and frequency of neuroligin mutations in ASD, we performed a mutation screening of NLGN3 and NLGN4X in a sample of 124 autism probands from the International Molecular Genetic Study of Autism Consortium (IMGSAC). We identified a new non-synonymous variant in NLGN3 (Thr632Ala), which is likely to be a rare polymorphism. Our data indicate that coding mutations in these genes are very rarely associated to ASD. 相似文献
110.
Loubinoux J Rio B Mihaila L Foïs E Le Fleche A Grimont PA Marie JP Bouvet A 《Journal of clinical microbiology》2005,43(7):3564-3566
A yellow-pigmented rod- to coccoid-shaped coryneform microorganism was isolated from the blood of a patient with acute myeloid leukemia. It was identified by 16S rRNA gene sequencing as a previously undescribed species of Janibacter. The isolate was susceptible to penicillins, aminoglycosides, fluoroquinolones, and glycopeptides. 相似文献