Conjugative IncFI plasmids carrying CTX-M-15 among Escherichia coli ESBL producing isolates at a University hospital in Germany

<p>Abstract</p> <p>Background</p> <p>Multi-drug-resistant, extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae, constitute an emerging public-health concern. Little data on the molecular epidemiology of ESBL producing <it>Escherichia coli </it>is available in Germany. Here we describe the prevalence and molecular epidemiology of ESBL producing-<it>Escherichia coli </it>isolates at a German University hospital.</p> <p>Methods</p> <p>We analysed 63 non-duplicate clinical ESBL isolates obtained over an 8-month period using PCR and sequence-based ESBL allele typing, plasmid replicon typing, phylogenetic group typing. Pulsed-field gel electrophoresis (PFGE) based genotyping and plasmid profiling was performed, as well as confirmatory DNA-based hybridization assays.</p> <p>Results</p> <p>Examination of the 63 <it>Escherichia coli </it>isolates revealed an almost equal distribution among the <it>E. coli </it>phylogenetic groups A, B1, B2 and D. High prevalence (36/63) of the CTX-M-15 gene was observed and an analysis of PFGE-based patterns revealed the presence of this CTX-M allele in multiple clones. Resistance to cefotaxime was a transferable trait and a commonly occurring 145.5 kb conjugative IncFI plasmid was detected in 65% of <it>E. coli </it>carrying the CTX-M-15 allele. The rate of transferable antibiotic resistances for GM, SXT, TET, GM-SXT-TET, SXT-TET and GM-TET was 33%, 61%, 61%, 27%, 44% and 11%, respectively. The remaining strains did not have a common IncFI plasmid but harboured transferable IncFI plasmids with sizes that ranged from 97 to 242.5 kb.</p> <p>Conclusion</p> <p>Our data demonstrate the presence of IncFI plasmids within the prevailing <it>E. coli </it>population in a hospital setting and suggest that the dissemination of CTX-M-15 allele is associated to lateral transfer of these well-adapted, conjugative IncFI plasmids among various <it>E. coli </it>genotypes.</p

How valid are current diagnostic criteria for dental erosion?

In principle, there is agreement about the clinical diagnostic criteria for dental erosion, basically defined as cupping and grooving of the occlusal/incisal surfaces, shallow defects on smooth surfaces located coronal from the enamel–cementum junction with an intact cervical enamel rim and restorations rising above the adjacent tooth surface. This lesion characteristic was established from clinical experience and from observations in a small group of subjects with known exposure to acids rather than from systematic research. Their prevalence is higher in risk groups for dental erosion compared to subjects not particularly exposed to acids, but analytical epidemiological studies on random or cluster samples often fail to find a relation between occurrence or severity of lesions and any aetiological factor. Besides other aspects, this finding might be due to lack of validity with respect to diagnostic criteria. In particular, cupping and grooving might be an effect of abrasion as well as of erosion and their value for the specific diagnosis of erosion must be doubted. Knowledge about the validity of current diagnostic criteria of different forms of tooth wear is incomplete, therefore further research is needed

Effect of different solutions on color stability of acrylic resin-based dentures

The aim of this study was to evaluate the effect of thermocycling and immersion in mouthwash or beverage solutions on the color stability of four different acrylic resin-based dentures (Onda Cryl, OC; QC20, QC; Classico, CL; and Lucitone, LU). The factors evaluated were type of acrylic resin, immersion time, and solution (mouthwash or beverage). A total of 224 denture samples were fabricated. For each type of resin, eight samples were immersed in mouthwashes (Plax-Colgate, PC; Listerine, LI; and Oral-B, OB), beverages (coffee, CP; cola, C; and wine, W), and artificial saliva (AS; control). The color change (SE) was evaluated before (baseline) and after thermocycling (T,), and after immersion in solution for 1 h (T-2), 3 h (T-3), 24 h (T-4), 48 h (T-5), and 96 h (T-6). The CIE Lab system was used to determine the color changes. The thermocycling test was performed for 5000 cycles. Data were submitted to three-way repeated-measures analysis of variance and Tukey&apos;s test (p &lt; 0.05). When the samples were immersed in each mouthwash, all assessed factors, associated or not, significantly influenced the color change values, except there was no association between the mouthwash and acrylic resin. Similarly, when the samples were immersed in each beverage, all studied factors influenced the color change values. In general, regardless of the solution, LU exhibited the greatest SE values in the period from T-1 to T-5; and QC presented the greatest SE values at T-6. Thus, thermocycling and immersion in the various solutions influenced the color stability of acrylic resins and QC showed the greatest color alteration.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Department of Dental Materials and Prosthodontics, Araçatuba Dental School, Univ Estadual Paulista - UNESP, Araçatuba, SP, Brazil.FAPESP: 2010/16962-

Prolongation of skin xenograft survival with modified cultured fibroblasts

Cyclosporine A, one of the most potent immunosuppressive drugs, mediates some of its immunosuppressive and nephrotoxic effects by enhancing transforming growth factor-beta(1) secretion ana receptor expression. In this experimental study, the effect of cyclosporine pretreatment of cultured dermal fibroblasts on xenogeneic tissue rejection after microimplantation beneath skin grafts was investigated. The effects of the site-specific immunosuppressive strategy on skin xenograft survival were tested. Because the skin is an immunological indicator of the rejection of composite tissue allografts, it was considered that this strategy could be used as a supportive therapy for composite tissue allo transplantation in the future. In the first stage of the study, fibroblast cultures obtained from skin biopsy samples from five rats were treated with different single doses of cyclosporine (100 to 3000 ng/ml), and transforming growth factor-beta(1) levels were measured in culture supernatants after 72 hours. In the second stage, 60 Sprague-Dawley rats were divided into six groups, as follows. For group I (sham), only the standard grafting procedure was performed. For group II, after the standard grafting procedure, rats were treated with in traperitoneal injections of 30 mg/kg (n = 5) or 10 mg/kg (n = 5) cyclosporine for 10 days. For group III, cultured fibroblasts obtained from skin biopsy samples from rats were treated with 100 or 500 ng/ml cyclosporine, and the cells were collected by light trypsinization and centrifugation after 72 hours. After the standard skin grafting procedure, modified fibroblasts were implanted between the graft and the recipient bed with a Pasteur pipet. For group IV, the same procedures as for group III were performed and then rats were treated with 10 mg/kg cyclosporine, administered intraperitoneally, for 10 days. For group V, in addition to standard grafting, unmodified fibroblasts (not treated with cyclosporine) were implanted between the graft and the recipient bed. For group VI, the same procedures as for group V were performed and then rats were treated with 10 mg/kg cyclosporine, administered intraperitoneally, for 10 days. The rejection process was observed macroscopically: and statistical significance was determined with the Mann-Whitney U test (p < 0.01). Graft survival times were significantly prolonged in groups III and IV, compared with groups I, II, V, and VI (p < 0.001). No difference between groups III and IV was observed. The novel finding of this investigation is that xenogeneic skin graft survival times could be prolonged with microimplantation of cyclosporine-treated cultured fibroblasts

Molecular characterization of microduplication 22q11.2 in a girl with hypernasal speech

We present a 12-year-old girl with karyotype 46,XX. A comparative genomic hybridization array revealed a 3.172-Mb microduplication on 22q11.2. This chromosome 22q11.2 region microduplication has been described in patients with variable phenotypes; a large majority of them have identical 3-Mb duplications. The girl presented mild mental motor retardation, facial dysmorphism consisting of a long narrow face, widely spaced eyes, downslanting palpebral fissures, broad nasal base, short philtrum, thin upper lip, micro/retrognathia, low set and retroverted ears, microcephaly, high-arched palate, hypoplastic teeth, and hypernasal speech. She had delayed psychomotor development and behavioral problems. Molecular characterization of patients differs greatly among reports and detailed molecular characterization and documentation are needed to better understand the effects of these duplications. This description of the phenotype of a patient with microduplication on 22q11.2 will contribute to the growing knowledge regarding deletions and duplications of the 22q11.2 region; this is important to conclude whether 22q11.2 duplication is a microduplication syndrome or not

CLINICAL, ANDROLOGICAL AND GENETIC CHARACTERISTICS OF PATIENTS WITH CONGENITAL BILATERAL ABSENCE OF VAS DEFERENS (CBAVD)

Congenital bilateral absence of the vas deferens (CBAVD) is a form of infertility with an autosomal recessive genetic background in otherwise healthy males. In this study, we examined the clinical and cystic fibrosis transmembrane-conductance regulator (CFTR) gene mutations in sixty patients with bilateral absence of vas deferens that applied to andrology clinic due to male factor infertility. Urogenital anomalies of vas deferens, seminal vesicle and epididymis were detected in our patient group. CFTR gene mutations, which are known to be frequent among cystic fibrosis patients, could not be detected in our patient group with that high frequency. Delta F508 mutations were detected in only 6% of patients. IVS8 polyT alleles were positive in 68% of patients. No 1677delTA mutations and M470V variants were detected in our patient group. However, sperm retrieval is almost always possible from CBAVD patients; secondary pathologies may also result defective spermatogenesis