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31.
Presence of the cfxA gene in Bacteroides distasonis 总被引:1,自引:0,他引:1
Avelar KE Otsuki K Vicente AC Vieira JM de Paula GR Domingues RM Ferreira MC 《Research in microbiology》2003,154(5):369-374
In this study we investigated the presence of the cfxA gene (encoding a class A beta-lactamase) in 73 strains of the Bacteroides fragilis group belonging to the species B. distasonis (34), B. vulgatus (14), B. thetaiotaomicron (8), B. merdae (6), B. caccae (9) and B. ovatus (2) isolated from human intestinal microflora of healthy children and adults. Employing specific primers to the cfxA gene, a 312-bp amplified fragment was obtained in 2 strains of B. vulgatus and 9 strains, the majority from children, of B. distasonis. The expression of this enzyme was analysed by determining the MICs to cefoxitin and cefotaxime and values varied from 2 to >256 microg/ml of both cefoxitin and cefotaxime. Sequence analysis of the amplicons corresponding to the cfxA gene from B. distasonis and B. vulgatus revealed identical sequences between these isolates and high similarity with other beta-lactamase genes of anaerobes such as cfxA of B. vulgatus (99%) and cfxA2 of Prevotella intermedia (99%), both sequences of which deposited in Genbank under accession numbers U38243 and AF118110, respectively. However, a fragment obtained from a B. distasonis strain (EC17-4) showed a unique RFLP profile and 87% nucleotide similarity with cfxA and cfxA2 genes. These results seem to suggest a dissemination of these resistance determinants among Bacteroides species. 相似文献
32.
García-Samaniego J Soriano V Miró JM Romero JD Bruguera M Castilla J Esteban JI Gonźlez J Lissen E Moreno A Moreno S Moreno-Otero R Ortega E Quereda C Rodríguez M Sánchez-Tapias JM;Spanish Hepatitis-HIV Consensus Panel 《HIV clinical trials》2002,3(2):99-114
Co-infection by human immunodeficiency virus and hepatitis B and C viruses is quite common because they share similar routes of transmission. The introduction of highly active antiretroviral therapy has significantly improved the life expectancy of HIV-infected patients in the last few years. However, chronic viral hepatitis represents an emerging cause of morbidity and mortality in this population, either as a result of end-stage liver disease or as a consequence of hepatotoxicity induced by antiretroviral drugs. The main goal of the Consensus Conference was to establish specific recommendations for the management of chronic viral hepatitis B and C in HIV-infected patients. The role of orthotopic liver transplantation for co-infected individuals with end-stage liver disease was also assessed. 相似文献
33.
34.
BACKGROUND: The consultation-liaison (C-L) psychiatrist is in an opportune position to undertake the tasks of education, training and assessment of performance as regards future physicians, psychiatrists, specialists in other branches and nurses. This paper describes the education and training programme in the Psychiatric-Psychosomatic C-L Service of Modena University Hospital. DESCRIPTION OF THE PROGRAMME: This programme consists of the following main activities: (1) daily group-case supervision, performed by the full-time psychiatrist together with the psychiatry residents of the C-L staff; (2) a bimonthly quality management meeting, which is part of a European project of measurement and improvement of quality of service; (3) weekly lectures on selected topics; (4) monthly tutorials in research techniques; (5) bimonthly presentations of literature reviews; (6) weekly clinical case conferences, which are the nucleus of the curriculum and which focus on the following main topics: 'the patients', 'the intervention' and 'the group', and (7) liaison meetings requested by non-psychiatric departments. CONCLUSIONS: A common denominator seen throughout the teaching and training activities of such a programme is the attitude of openness and effort toward integration which should be the C-L psychiatrist's distinguishing mark, in the context of the general hospital. 相似文献
35.
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
36.
Comparative effects of estrogens plus androgens and tibolone on bone, lipid pattern and sexuality in postmenopausal women 总被引:4,自引:0,他引:4
Castelo-Branco C Vicente JJ Figueras F Sanjuan A Martínez de Osaba MJ Casals E Pons F Balasch J Vanrell JA 《Maturitas》2000,34(2):161-168
BACKGROUND: The main goals of estrogen replacement therapy (ERT) are the prevention of osteoporosis and cardioprotection and the improvement of quality of life (QL). Androgens and tibolone therapy may increase bone mineral density (BMD) to a greater extent than ERT and offer an increase in QL. Lipid and cardiovascular effects, however, are still a major concern. AIM: To evaluate whether the addition of a weak androgen to ERT may improve postmenopausal bone loss and sexual activity without adverse effects on lipid pattern and to compare these effects with those observed after tibolone therapy. SUBJECTS AND METHODS: This prospective study enrolled 120 surgical postmenopausal women; of these, 96 completed the 1-year follow-up. Patients were allocated to one of four groups. The first group (A; n = 23) received 4 mg of estradiol valerate plus 200 mg of enanthate of dihydroandrosterone im monthly. The second group (E; n = 26) received 50 microg/day of transdermal 17-b-estradiol continuously; the third (T; n = 23) received 2.5 mg of tibolone every day; and finally, the fourth group (C; n = 24) constituted a treatment-free control group. Bone mass (dual X-ray absorptiometry), serum total cholesterol, HDL, LDL, triglycerides, apolipoproteins A1 and B and sexual activity were evaluated before starting therapy and at the end of follow-up. RESULTS: All active treatment groups showed an increase in BMD. This increase was higher in the A treatment group (4.08% P < 0.01). Sexuality improved significantly with therapy; however, tibolone and androgens increased scores to a greater extent than ERT. Androgen therapy was associated with significant increases in total cholesterol, LDL and triglycerides. Cholesterol and LDL fall into groups E and T, HDL into groups A and T and triglycerides in group T only. CONCLUSION: The combined regimen of androgens and ERT increased vertebral bone mass and enhance sexual activity in postmenopausal women equal to that of tibolone and to a greater extent than ERT alone; its effects on lipids, however, are clearly adverse. 相似文献
37.
P G Natali M A Pellegrino L Walker S Ferrone R A Reisfeld 《Journal of immunological methods》1979,25(3):255-264
The human beta2-microglobulin antigen-antibody system was used as a model to illustrate the versatility of a microradioimmunoassay technique using protein A-bearing Staphylococcus aureus Cowan I strain (SACI) bacteria as a non-specific immunoadsorbent in place of a second antibody. Experimental conditions are described for a sensitive microassay which makes it possible to process large numbers of samples more rapidly and with minimum handling. Furthermore, SACI coated with specific antibodies by mixing with unfractionated antisera are a versatile reagent not only for radioimmunoassays but also for use as molecular probes to characterize cell surface antigens. Antibody-coated SACI could be lyophilized and proved extremely stable in storage thus providing a unique advantage for use in binding inhibition assays and as versatile reagent for clinical and investigative immunology. 相似文献
38.
O Segatto C Secchi A Berrini P G Natali 《International journal of tissue reactions》1986,8(3):225-229
Splenic null cells of normal mice have been shown to undergo phenotypic induction of Thy 1.2 antigen by various thymic extracts. This experimental model has been employed in characterizing the Thy 1.2 inducing ability of an acid lysate from calf thymus and its various fractions. Incubation of splenocytes from C3H/He mice with unfractionated Thymomodulin induces a dose-response percent increase in the Thy 1.2 antigen bearing cells (9.28 +/- 2.6%, p less than 0.05). Comparable increase appears in fractions 5B (9.46 +/- 0.55%, p less than 0.001) and 5C (8.09 +/- 3%, p less than 0.005), obtained by ultrafiltration and containing peptides of m.w. 600-10,000 d and less than 600 d, respectively. The activity is confined to the acid fraction (6.61 +/- 0.54%, p less than 0.001) isolated by isoelectrofocusing. Control lysate from pig duodenal mucosa was devoid of Thy 1.2 inducing activity. The present findings indicate that Thymomodulin possesses Thy 1.2 inducing capacity on murine null cells and that such activity is maintained and enhanced after various fractionation procedures. 相似文献
39.
Summary When KB cells were infected either with the fowl plague (FPV) Rostock strain (Hav1N1) or the WSN (H0N1) strain of influenza A virus the yield of cell-associated haemagglutinin and neuraminidase polypeptides was essentially comparable, but virus particles were not produced in the FPV-KB system. WSN virus-infected KB cells synthesized normal amounts of mature virus particles and had all the characteristics of a permissive replication cycle. Biosynthesis and transport of RNP antigen from nucleus to cytoplasm of infected cells were traced by immunofluorescent staining at 4 and 8 hours after the beginning of infection. While the fluorescent-stained material was totally confined to the nuclei in FPV-infected KB cells, RNP antigen migrated out of the nucleus during the replicative cycle of WSN virus in the same host cell. Patterns of virus-specific protein synthesis were studied by pulse-labelling with35S-methionine. The most significant feature concerned the amplification of synthesis of virus-induced matrix (M) protein which did not occur in FPV-infected cells but occurred normally during WSN infection. The different patterns of replication in the same host cell when infected by different influenza A viruses is discussed.With 3 Figures 相似文献
40.
M. Montes D. Vicente O. Esnal G. Cilla E. Pérez-Trallero 《Clinical microbiology and infection》2008,14(1):91-93
Human metapneumovirus (hMPV) genotypes A and B show epidemiological and probably clinical differences. This report describes a fast and simple PCR–restriction fragment length polymorphism (PCR-RFLP) assay, involving digestion of the fusion protein gene with Tsp 509I, that allows lineages A1, A2, B1 and B2 to be distinguished. The assay should help in elucidating the epidemiology of hMPV, and possibly in predicting the severity of clinical infection. 相似文献