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71.
We have identified and sequenced the genes encoding the quinolone-resistance determining region (QRDR) of ParC and GyrA in fluoroquinolone-susceptible and -resistant Streptococcus suis clinical isolates. Resistance is the consequence of single point mutations in the QRDRs of ParC and GyrA and is not due to clonal spread of resistant strains or horizontal gene transfer with other bacteria.  相似文献   
72.
Fonsecaea pedrosoi is the most common etiologic agent of chromoblastomycosis. F. pedrosoi and other dematiaceous fungi are usually identified by morphologic studies. We have developed a duplex polymerase chain reaction (PCR) targeting the ribosomal DNA for rapid and more specific identification of the genus Fonsecaea. DNA samples from 103 isolates of Fonsecaea species and other dematiaceous fungi were amplified by PCR using universal and specific primers targeting ITS1-5.8S-ITS2 region of the ribosomal DNA. Universal primers were used for detection of non-Fonsecaea DNA. Fonsecaea-specific PCR product was found in 70 (68.0%) isolates including 4 strains that did not develop conidiogenesis. Thirty non-Fonsecaea and 3 Fonsecaea compacta isolates were negative by duplex PCR. These results were confirmed by DNA sequencing analysis indicating the high specificity of the duplex PCR assay. In conclusion, the duplex PCR is a rapid and specific assay for identification of Fonsecaea isolates mainly for the strains that are difficult to identify by morphologic methods.  相似文献   
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Graefe's Archive for Clinical and Experimental Ophthalmology - The objective of this study was to analyze the differences in blinking kinematics of spontaneous and voluntary blinks using for...  相似文献   
74.
Despite of controls and preventive measures implemented along the food chain, infection with non‐typhoidal Salmonella (NTS) remains one of the major causes of foodborne disease worldwide. Poultry is considered one of the major sources of NTS. This has led to the implementation of monitoring and control programmes in many countries (including Spain) to ensure that in poultry flocks infection is kept to a minimum and to allow the identification and monitoring of circulating NTS strains and their antimicrobial resistance (AMR) phenotypes. Here, we investigated the information from the monitoring programme for AMR in Salmonella from poultry in Spain in 2011–2017 to assess the diversity in phenotypic resistance and to evaluate the programme's ability to detect multi‐resistance patterns and emerging strains in the animal reservoir. Data on serotype and AMR to nine antimicrobials obtained from 3,047 NTS isolates from laying hens (n = 1,060), broiler (n = 765) and turkey (n = 1,222) recovered during controls performed by the official veterinary services and food business operators were analysed using univariate and multivariate methods in order to describe host and serotype‐specific profiles. Diversity and prevalence of phenotypic resistance to all but one of the antimicrobials (colistin) were higher in NTS from broiler and turkey compared with laying hen isolates. Certain combinations of serotype and AMR pattern (resistotype) were particularly linked with certain hosts (e.g. susceptible Enteritidis with laying hens, multi‐drug resistant (MDR) Derby in turkey, MDR Kentucky in turkey and broiler). The widespread presence of certain serotype‐resistotype combinations in certain hosts/years suggested the possible expansion of MDR strains in the animal reservoir. This study demonstrates the usefulness of the analysis of data from monitoring programmes at the isolate level to detect emerging threats and suggests aspects that should be subjected to further research to identify the forces driving the expansion/dominance of certain strains in the food chain.  相似文献   
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The HTLV-1 envelope gene of 12 TSP/HAM patients from two endemic areas of southwest Colombia (Tumaco and Buenaventura) was amplified by nested PCR, sequenced, and compared with previously reported HTLV-1 envelope sequences from isolates worldwide. In general, the sequence divergences among all Colombian samples ranged from 0.1 to 1.6%. Some amino acid substitutions, referring to the ATK-1 prototype strain in the surface domain gp46 and in p21, were highly prevalent in southwest Colombia, suggesting a geographical clustering of mutations in the envelope gene. The phylogenetic analysis showed that the Colombian isolates belong to the HTLV-1a lineage with minor subgroups. The genetic distance between Colombian and Japanese isolates ranged from 0.1 to 1.8%; in comparison, the genetic distance between Colombian and Caribbean isolates ranged from 0.4 to 2.2%. Our results strongly suggest that the actual quasispecies populations in southwest Colombia have been generated by separate, differently timed introductions of virus.  相似文献   
80.
Objective: Cardiac amyloid infiltration can lead to systolic heart failure (HF) or to conduction disorders (CD). Patients with transthyretin (ATTR) amyloidosis are particularly exposed. We sought to determine the prevalence of ATTR and AL among patients >60?years admitted with CD or unexplained systolic HF and increased wall thickness.

Materials and Methods: We studied 143 patients (57% males, 79?±?9?years) with HF (N?=?28) or CD requiring pacemaker implantation (N?=?115). In total, 139 (97%) patients (28 with HF and 111 with CD) underwent 99mTc-DPD scintigraphy to detect ATTR, and 105 (73%; 19 HF and 86?CD) underwent AL screening.

Results: Five patients (4%; 95%CI:0–7%) exhibited wild-type ATTR (ATTRwt) amyloidosis, 2 (2%; 95%CI:0–4%) had CD and 3 (11%; 95%CI:0–23%) HF. No patient showed AL. The 2 ATTRwt patients with CD were previously asymptomatic, did not show classical ECG signs and exhibited mild LV hypertrophy with preserved LVEF. By contrast, all ATTRwt patients with HF had ECG and echocardiographic signs of amyloid. During a mean follow-up of 18?±?11?months, 3(60%) patients with ATTRwt amyloidosis (1?CD and 2 HF) and 14(10.4%) without died.

Conclusion: Prevalence of ATTRwt amyloidosis in patients with CD requiring pacemaker is low. Although, additional studies are needed, prevalence seems to be higher in elderly patients with systolic HF.  相似文献   

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