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2.
'Cialit' as a tissue preservative: a microbiological assessment   总被引:1,自引:0,他引:1  
We describe bacterial contamination of a 'Cialit'-preserved cartilage bank which continued after a variety of changes to the harvesting and preservation protocols during a 3-year prospective study. Our results emphasize the importance of adequate tissue bank microbiological screening. Alternative methods of tissue preservation should be considered.  相似文献   
3.
Bordetella pertussis is known to release a factor which promotes the loss of ciliated respiratory epithelium and copurifies with a soluble peptidoglycan (PG) fragment termed tracheal cytotoxin (TCT). The objective of this study was to determine whether pertussis organisms turn over and release PG derivatives in addition to TCT. B. pertussis Tohama (phase III) was grown in liquid Stainer-Scholte medium containing [3H]diaminopimelic acid (DAP) to label PG specifically, washed to remove free label, and suspended in fresh medium without [3H]DAP. Molecular sieve chromatography of supernatants obtained from such cultures revealed a single included peak of 3H, the elution volume of which corresponded roughly to a disaccharide peptide monomer standard (ca. 10(3) daltons). This material (i) contained [3H]DAP in acid-hydrolyzable linkage, (ii) comigrated with 1,6-anhydro-N-acetylmuramic acid-containing disaccharide peptides on paper chromatography, (iii) was resistant to degradation by mild alkali, and (iv) was indistinguishable from authentic TCT by high-voltage paper electrophoresis and two reversed-phase high-performance liquid chromatography systems. Together, the data suggest that B. pertussis releases a markedly homogeneous set of PG fragments, consisting principally of TCT, and that TCT is possibly a nonreducing, anhydromuramic acid-containing fragment or a cyclic PG derivative.  相似文献   
4.
Maternal effects in atopic disease   总被引:2,自引:0,他引:2  
  相似文献   
5.
Eighteen chronic schizophrenic patients who had shown improvement from increased maintenance dosages of cis(z)-flupenthixol decanoate were entered into a double-blind study in which half of the patients were randomly allocated to be maintained on 50% of their pre-trial dosage. During the 44 week study the reduced dosage group showed increased morbidity and one-third of these patients had a schizophrenic relapse. The greatest deterioration occurred in patients reduced from above to below 200 mg cis(z)-flupenthixol decanoate biweekly. A review of all the patients entered into the study showed a relationship between deterioration of schizophrenic and depressive features and cis(z)-flupenthixol plasma levels which reflected the administered dosage. Prolactin levels in general did not reflect control of schizophrenic symptoms. Side-effects were few, and there was no emergence of tardive dyskinesia. A multicentre trial is needed for further evaluation.  相似文献   
6.
7.
Primarily saprophytic in nature, fungi of the genus Acremonium are a well-documented cause of mycetoma and other focal diseases. More recently, a number of Acremonium spp. have been implicated in invasive infections in the setting of severe immunosuppression. During the course of routine microbiological studies involving a case of fatal mycosis in a nonmyeloablative hematopoietic stem cell transplant patient, we identified a greater-than-expected variation among strains previously identified as Acremonium strictum by clinical microbiologists. Using DNA sequence analysis of the ribosomal DNA intergenic transcribed spacer (ITS) regions and the D1-D2 variable domain of the 28S ribosomal DNA gene (28S), the case isolate and four other clinical isolates phenotypically identified as A. strictum were found to have <99% homology to the A. strictum type strain, CBS 346.70, at the ITS and 28S loci, while a sixth isolate phenotypically identified only as Acremonium sp. had >99% homology to the type strain at both loci. These results suggest that five out of the six clinical isolates belong to species other than A. strictum or that the A. strictum taxon is genetically diverse. Based upon these sequence data, the clinical isolates were placed into three genogroups.  相似文献   
8.

Objective

To develop a consensus-based set of generic competencies in antimicrobial prescribing and stewardship for European prescribers through a structured consensus procedure.

Methods

The RAND-modified Delphi procedure comprised two online questionnaire rounds, a face-to-face meeting between rounds, and a final review. Our departure point was a set of competencies agreed previously by consensus among a UK multi-disciplinary panel, and which had been subsequently revised through consultation with ESCMID Study Group representatives. The 46 draft competency points were reviewed by an expert panel consisting of specialists in infectious diseases and clinical microbiology, and pharmacists. Each proposed competency was assessed using a nine-point Likert scale, for relevance as a minimum standard for all independent prescribers in all European countries.

Results

A total of 65 expert panel members participated, from 24 European countries (one to six experts per country). There was very high satisfaction (98%) with the final competencies set, which included 35 competency points, in three sections: core concepts in microbiology, pathogenesis and diagnosing infections (11 points); antimicrobial prescribing (20 points); and antimicrobial stewardship (4 points).

Conclusions

The consensus achieved enabled the production of generic antimicrobial prescribing and stewardship competencies for all European independent prescribers, and of possible global utility. These can be used for training and can be further adapted to the needs of specific professional groups.  相似文献   
9.
Staphylococcus aureus isolates carrying the genes that encode for Panton-Valentine leucocidin (PVL), a highly potent toxin, have been responsible for recent outbreaks of severe invasive disease in previously healthy children and adults in the United States of America and Europe. To determine the frequency of PVL-positive isolates sent to the Staphylococcus Reference Unit (United Kingdom) for epidemiological purposes, we tested 515 isolates of S. aureus, and 8 (1.6%) were positive for the PVL locus. A further 470 isolates were selected to explore the association of PVL-positive S. aureus with clinical disease. Of these, 23 (4.9%) were PVL positive and most were associated with skin and soft tissue infections (especially abscesses). The PVL genes were also detected in isolates responsible for community-acquired pneumonia, burn infections, bacteremia, and scalded skin syndrome. Genotyping by pulsed-field gel electrophoresis and multilocus sequence typing revealed that the PVL-positive isolates were from diverse genetic backgrounds, although one prevalent clone of 12 geographically dispersed methicillin-resistant S. aureus (MRSA) isolates was identified (ST80). All 12 isolates were stapylococcal cassette chromosome mec type IVc, had an agr3 allele, and shared a common toxin gene profile (sea-see, seg-sej, eta, etb, and tst negative but etd positive). ST80 strains with similar genetic characteristics have been responsible for community-acquired infections in France and Switzerland. The remaining PVL-positive isolates were mostly methicillin-sensitive S. aureus and belonged to 12 different sequence types, including ST22 and ST30, which are closely related to the most prevalent MRSA clones in United Kingdom hospitals, EMRSA-15 and EMRSA-16, respectively.  相似文献   
10.
Identification of medically relevant yeasts can be time-consuming and inaccurate with current methods. We evaluated PCR-based detection of sequence polymorphisms in the internal transcribed spacer 2 (ITS2) region of the rRNA genes as a means of fungal identification. Clinical isolates (401), reference strains (6), and type strains (27), representing 34 species of yeasts were examined. The length of PCR-amplified ITS2 region DNA was determined with single-base precision in less than 30 min by using automated capillary electrophoresis. Unique, species-specific PCR products ranging from 237 to 429 bp were obtained from 92% of the clinical isolates. The remaining 8%, divided into groups with ITS2 regions which differed by /=99%. Seven clinical isolates contained ITS2 sequences that did not agree with their phenotypic identification, and ITS2-based phylogenetic analyses indicate the possibility of new or clinically unusual species in the Rhodotorula and Candida genera. This work establishes an initial database, validated with over 400 clinical isolates, of ITS2 length and sequence polymorphisms for 34 species of yeasts. We conclude that size and restriction analysis of PCR-amplified ITS2 region DNA is a rapid and reliable method to identify clinically significant yeasts, including potentially new or emerging pathogenic species.  相似文献   
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