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51.
Clonal Distribution of Methicillin-Resistant Staphylococcus aureus in Poland 总被引:3,自引:0,他引:3
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T. Leski D. Oliveira K. Trzcinski I. Santos Sanches M. Aires de Sousa W. Hryniewicz H. de Lencastre 《Journal of clinical microbiology》1998,36(12):3532-3539
We report on a study of 158 methicillin-resistant Staphylococcus aureus (MRSA) clinical isolates obtained from 1990 to 1996 in 18 different hospitals in Poland. All isolates were recovered from infection and carriage sites of patients, carriage sites of health care personnel, and hospital environment samples. Fifty-seven MRSA strains described here were studied previously and these were divided into two different clusters according to the degree of heterogeneity of methicillin resistance expression. The aim of this study was to extend the correlation between the two clusters and identify the clonal identities among all isolates by a combination of different methodologies: (i) analysis of mecA polymorphs and Tn554 insertion patterns and (ii) determination of pulsed-field gel electrophoresis patterns of chromosomal SmaI digests. Ninety-seven of 158 strains showed a heterogeneous expression of resistance to methicillin. Among these, 75 (77.3%) were ClaI-mecA type I, ClaI-Tn554 type NH (NH, no homology with transposon Tn554), and pulsed-field gel electrophoresis (PFGE) pattern A (I::NH::A); 10 isolates were III::B::M (10.3%); and the remaining clones included a few or single isolates. The isolates with homogeneous expression of resistance to methicillin (n = 61) were predominantly ClaI-mecA type III (49 of 61 [80.3%]) but had great variability in their ClaI-Tn554 and PFGE patterns. This study confirmed the existence of two main clusters of MRSA in Poland. 相似文献
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53.
How to use Chlamydia antibody testing in subfertility patients 总被引:1,自引:9,他引:1
Screening for tubal factor subfertility by means of Chlamydia antibody
testing (CAT) was introduced into the initial work-up of subfertile couples
several years ago. The results reported, however, are heterogeneous, and no
uniformity exists in cut-off levels of titres, or in definitions of tubal
factor subfertility. We performed a prospective cohort study to evaluate
the implications of varying the definitions of tubal pathology and of
modifying the cut-off levels on the clinical impact of CAT in predicting
tubal factor subfertility. In 227 consecutive patients who attended our
fertility clinic, the Chlamydia IgG antibody titre was determined and
related to tuboperitoneal abnormalities at laparoscopy as a reference
standard. According to received operating characteristic (ROC) curve
analysis, a titre of 16 is the optimum cut-off level. Increasing the
cut-off level improves specificity and positive likelihood ratio (LR+), at
the expense of sensitivity and negative LR (LR-). Changing the definition
of tubal factor subfertility from unspecified tuboperitoneal abnormalities
into extensive adhesions and/or bilateral distal tubal occlusion improves
LR+, LR- and kappa significantly. We conclude that CAT is more accurate in
predicting severe distal tubal pathology than unspecified tuboperitoneal
abnormalities. Although from a statistical point of view a titre of 16 is
the optimum cut-off level, from a clinical point of view 32 or 64 may be
preferable, depending on the aim of screening and the inception cohort.
相似文献
54.
Anxiety during pregnancy and fetal attachment after in-vitro fertilization conception 总被引:3,自引:4,他引:3
McMahon CA; Ungerer JA; Beaurepaire J; Tennant C; Saunders D 《Human reproduction (Oxford, England)》1997,12(1):176-182
The aim of this study was to compare 70 couples who had conceived by in-
vitro fertilization (IVF) with 63 matched controls for the prevalence of
anxiety and quality of attachment to the baby during pregnancy. Results for
mothers showed no group differences using a global measure of anxiety, the
Spielberger State-Trait Anxiety Inventory. However, pregnancy-specific
measures revealed significantly higher levels of anxiety in IVF mothers
about the survival and normality of their unborn babies, about damage to
their babies during childbirth and about separating from their babies after
birth. When IVF mothers were differentiated according to the number of
treatment cycles, more differences in anxiety level were revealed, with
most increases occurring in mothers who had experienced two or more
treatment cycles. IVF fathers did not differ from controls on the global
anxiety measure. No data on pregnancy-specific anxiety were available for
fathers. Neither IVF mothers nor IVF fathers differed from controls on
measures of attachment to the baby during pregnancy. Results are discussed
in the context of the need for researchers to employ differentiated and
issue-specific measures to identify concerns that may be unique to IVF
couples. Clinical implications regarding the need for psychological support
during pregnancy are also discussed.
相似文献
55.
56.
Cardoso O Leitão R Figueiredo A Sousa JC Duarte A Peixe LV 《Microbial drug resistance (Larchmont, N.Y.)》2002,8(2):93-97
Resistance to carbapenems is emerging, and it is a great problem to therapeutics. Three isolates of Pseudomonas aeruginosa from a Portuguese hospital identified in urine and sputum, in 1995, presented a high-level resistance to imipenem (> 32 mg/L). Afterward, one isolate of P. aeruginosa recovered from urine of an ambulatory patient in 1998 showed high resistance to imipenem and meropenem. The resistance to carbapenems in these strains was associated with the production of a class B beta-lactamase, as was demonstrated by imipenem hydrolysis and inhibition by EDTA. Using primers described for bla(IMP) and bla(VIM), the amplification of the latter was observed in all isolates and a VIM-2 metallo-enzyme was identified. The pulsed-field gel electrophoresis (PFGE) patterns of these isolates were indistinguishable, suggesting dissemination to the community of this VIM-2 producer. 相似文献
57.
58.
59.
Melter O Aires de Sousa M Laskafeldová K Urbásková P Wünschová M de Lencastre H 《Microbial drug resistance (Larchmont, N.Y.)》2004,10(3):218-223
The aim of this study was to define the endemic clones of methicillin-resistant Staphylococcus aureus (MRSA) among strains collected between September, 2001, and February, 2003, at the regional hospital of Novy Jicín, Czech Republic. The isolates were characterized by susceptibility tests, HindIII ribotyping, and pulsed-field gel electrophoresis. Representatives of each clonal type were analyzed by multilocus sequence typing and staphylococcal cassette chromosome mec (SCCmec) typing. The prevalence of the most important macrolide (ermA, ermB, ermC, and msrA) and aminoglycoside (aac6'-aph2", aph3', and ant4') resistance genes was evaluated as well. Our results document the existence of two international MRSA clones: (1) the Iberian clone (ST247:SCCmec IA:PFGE A:ribotype H2), endemic in the hospital and associated to a single multiresistant phenotype; and (2) clone EMRSA-15 (ST22:SCCmec IV:PFGE H-ribotype H7), appearing in the beginning of 2002 and associated with three phenotypes. These two clones could be distinguished by antibiogram, distribution of macrolide and aminoglycoside resistance genes (ermA, aac6'-aph2", ant4' versus ermC and msrA in a few isolates), production of beta-lactamase, and presence of enterotoxin A (in the Iberian clone). 相似文献
60.
Aires De Sousa M Miragaia M Sanches IS Avila S Adamson I Casagrande ST Brandileone MC Palacio R Dell'Acqua L Hortal M Camou T Rossi A Velazquez-Meza ME Echaniz-Aviles G Solorzano-Santos F Heitmann I de Lencastre H 《Journal of clinical microbiology》2001,39(6):2197-2205
Four hundred ninety-nine methicillin-resistant Staphylococcus aureus (MRSA) isolates recovered from 1996 to 1998 from 22 hospitals in five countries of Latin America-Argentina, Brazil, Chile, Uruguay and Mexico-were examined for antimicrobial susceptibility and clonal type in order to define the endemic clones in those hospitals. The hybridization of ClaI restriction digests with the mecA- and Tn554-specific DNA probes combined with pulsed-field gel electrophoresis of chromosomal SmaI digests (ClaI-mecA::ClaI-Tn554::PFGE clonal types) documented not only the predominance and persistence of the Brazilian clone (XI::B::B) in Brazil (97%) and Argentina (86%) but also its massive dissemination to Uruguay (100%). Moreover, a close relative of the Brazilian clone (XI::kappa::B) was highly represented in Chile (53%) together with a novel clone (47%) (II::E'::F) resistant to pencillin, oxacillin, ciprofloxacin, chloramphenicol, clindamycin, erythromycin, and gentamicin. A unique clonal type (I::NH::M) was detected in Mexico among pediatric isolates and was resistant to penicillin, oxacillin, and gentamicin only. This study clearly documented the very large capacity for geographic expansion and the persistence of the Brazilian clone, contributing not only to the increasing uniformity of the MRSA in South America but worldwide as well. 相似文献