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1.
Phenotypic and genetic features of enteropathogenic Escherichia coli isolates from diarrheal children in the Ribeirão Preto metropolitan area,São Paulo State,Brazil 下载免费PDF全文
André Pitondo‐Silva Gerson Nakazato Juliana P. Falcão Kinue Irino Roberto Martinez Ana Lúcia C. Darini Rodrigo Tavanelli Hernandes 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2015,123(2):128-135
This study was designed to characterize a collection of 60 enteropathogenic Escherichia coli (EPEC) isolates from diarrheic feces of patients in the Ribeirão Preto metropolitan area regarding different phenotypic and molecular features. We examined antibiotic resistance profiles, occurrence of virulence factors‐encoding genes, intimin subtypes and the correlation of serotypes among typical (tEPEC) and atypical (aEPEC) EPEC isolates. The results demonstrated that atypical EPEC was more heterogeneous than typical EPEC concerning the characteristics investigated and 45.2% do not belong to classical EPEC serogroups. Intimin subtype β was the most frequent among the EPEC isolates (46.7%), being detected in both tEPEC and aEPEC. The majority of aEPEC isolates presented localized adherence‐like (LAL) pattern to HEp‐2 cells, although aEPEC isolates displaying diffuse adherence (DA) or non‐adherent were also detected. High prevalence of antimicrobial resistance was found for ampicillin, cephalothin, sulfonamide and tetracycline. In general, tEPEC isolates were more resistant to the antimicrobials tested than aEPEC isolates. 相似文献
2.
Spread of an Enterococcus faecalis sequence type 6 (CC2) clone in patients undergoing selective decontamination of the digestive tract 下载免费PDF全文
Izaskun Muruzábal‐Lecumberri Cecilia Girbau Andrés Canut Rodrigo Alonso Aurora Fernández‐Astorga 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2015,123(3):245-251
Enterococcus faecalis (E. faecalis) is a common cause of nosocomial infection in immunocompromised patients. The presence and dissemination of high‐risk clonal complexes, such as CC2, is an ongoing problem in hospitals. The aim of this work was to characterize 24 E. faecalis isolates from ICU patients undergoing selective decontamination of the digestive tract (SDD) by phenotypical (antimicrobial susceptibility) and genotypical (presence of virulence genes, RAPD‐PCR and MLST) methods. Our results showed high prevalence of the ST6 E. faecalis clone (91.6%), especially adapted to the hospital environment, with a multidrug resistance pattern and a multitude of putative virulence genes. In addition, ST179 (4.2%) and ST191 (4.2%) were detected. By RAPD–PCR analysis, the 22 isolates identified as ST6 showed six different DNA patterns, while the two remaining isolates, ST179 and ST191, showed two additional profiles. CC2 is a known clonal complex with high adaptability to hospital environment and worldwide distribution. The high prevalence of the ST6 clone in the studied population could be related to the presence of gentamicin in the SDD mixture since most strains were gentamicin resistant. Consequently, strict surveillance should be applied for rapid detection and control of this clone to prevent future spread outside the ICU. 相似文献
3.
4.
Rodrigo Pacheco 《中国神经再生研究》2019,(12)
正The emerging role of gut microbiota as a key player in the development of neurodegenerative disorders:Mammals have evolved togetherwithcommensalmicrobiotatoestablishasymbioticrelationship in which they regulate reciprocally by synthesizing and responding to several common chemical substances. In this regard, gut microbiota 相似文献
5.
Mariana Spitz Alexandre Aluízio Costa Machado Rodrigo do Carmo Carvalho Fernanda Martins Maia Monica Santoro Haddad Dagoberto Calegaro Milberto Scaff Egberto Reis Barbosa 《Movement disorders》2006,21(9):1520-1522
We report on 3 patients with pseudoathetosis, which are involuntary, slow, writhing movements due to loss of proprioception. 相似文献
6.
Rodrigo O Perez Angelita Habr-Gama Igor Proscurshim Fábio G Campos Desiderio Kiss Joaquim Gama-Rodrigues Ivan Cecconello 《Journal of gastrointestinal surgery》2007,11(11):1431-8; discussion 1438-40
BACKGROUND: The role of local excision for pT2 distal rectal cancer has been challenged because of the observation of high rates of lymph node metastases and local failure. However, neoadjuvant chemoradiation therapy (CRT) has led to increased local disease control and significant tumor downstaging, possibly decreasing rates of lymph node metastases. In this setting, a possible role for local excision of ypT2 has been suggested. METHODS: A total of 401 patients with distal rectal cancer underwent neoadjuvant CRT. Tumor response assessment was performed after at least 8 weeks from CRT completion. One hundred and twelve patients with complete clinical response were not immediately operated on and were excluded from the study, and 289 patients with incomplete clinical response were managed by radical surgery. Patients with final pathological stage ypT2 were analyzed to determine the risk of unfavorable pathological features that could represent unacceptable risk for local failure after local excision. RESULTS: Eighty-eight (30%) patients had ypT2 rectal cancer. Final ypT status was not associated with pretreatment radiological staging (p = 0.62). ypT status was significantly associated with the risk of lymph node metastases, risk of perineural and vascular invasion, and recurrence (p = 0.001). Lymph node metastases were present in 19% of patients with ypT2 rectal cancer. The risk of lymph node metastases in ypT2 was associated with the presence of perineural invasion (47% vs 4%; p = <0.001), vascular invasion (59% vs 6%; p < 0.001), and decreased mean interval CRT surgery (12 vs 18 weeks; p < 0.001), but not with mean tumor size (3.2 vs 3.1 cm; p = 0.8). Disease-free and overall survival rates were significantly better for patients with ypT2N0 (p = 0.02 and 0.006, respectively). Fifty-five (63%) patients with ypT2 had at least one unfavorable pathological feature for local excision (lymph node metastases, vascular or perineural invasion, mucinous type or tumor size >3 cm). CONCLUSION: Lymph node metastases were present in 19% of patients with ypT2 and were significantly associated with poor overall and disease-free survival rates. The risk of lymph node metastases could not be predicted by radiological staging or tumor size. Radical surgery should be considered the standard treatment option for ypT2 rectal cancer after CRT. 相似文献
7.
Ignacio Alvarez Alvarez M.D. Pedro Sanchez Lazo Ph.D. Sofia Ramos Gonzalez Ph.D. J. Pablo Rodrigo Tapia M.D. Faustino Nunez Batalla M.D. Carlos Suarez Nieto M.D. 《American journal of otolaryngology》1997,18(6):375
Purpose: Increasingly, evidence has shown that human papillomavirus (HPV) plays a role in the induction of certain carcinomas. The presence of HPV sequences in 56 previously untreated oral and pharyngolaryngeal carcinomas was examined by the polymerase chain reaction (PCR).Materials and Methods: After DNA extraction, samples underwent 40 replication cycles with specific oligonucleotide primers corresponding to sequences from the E6 open-reading frame of HPV-6b, HPV-16, and HPV-18. To determine the E6 genomic integration, positive samples were processed with specific primers for the corresponding HPV L1 genes. Genomic HPV DNA cloned into PBR 322 was used as positive control.Results: HPV E6 DNA of the 6b and 16 types was detected in 14 patients (25%). The L1 gene was not present.Conclusion: Detected HPV E6 DNA might be integrated into the cell genome in the positive cases as indicated by the absence of the L1 gene-coding for the viral capside. Histological and clinical parameters, such as tumor location, degree of differentiation, stage, recurrence, and survival rates, were unrelated to the presence of HPV. 相似文献
8.
The smoking control policies recommended by the World Health Organisation have achieved a slight decrease in smoking prevalence in developed countries, although associated mortality is still very high. The use of tobacco products other than cigarettes and even medicinal nicotine (known as nicotine replacement therapy [NRT]) has been proposed as a risk reduction strategy. Among the tobacco products with less individual risk than cigarettes would be any type of tobacco without smoke (smokeless) with a low content in nitrosamines and modified cigarettes; both forms included under the PREP (Potentially Reduced Exposure Products) concept. The idea would be to promote these products among patients who cannot quit smoking or wish to reduce their risk without giving up nicotine intake. The possible effects of risk reduction strategies, including PREP, on the decreased prevalence and morbidity and mortality are reviewed, and the possible implications that this measure could have in Spain are analysed. Tobacco control measures in Spain have only been made recently and are still insufficient. Therefore, the current priority in Spain is to develop control policies that have proven to be more than effective. The marketing and advertising of new tobacco products, even with reduced potential risk, seems more a serious threat than an opportunity for developing smoking control policies. 相似文献
9.
Ramón Rodrigo Hernán Prat Walter Passalacqua Julia Araya Cristián Guichard Jean P B?chler 《Hypertension research》2007,30(12):1159-1167
This study investigated the association of blood pressure with blood oxidative stress-related parameters in normotensive and hypertensive subjects. A cross-sectional design was applied to 31 hypertensive patients and 35 healthy normotensive subjects. All subjects were men between the ages of 35 and 60 years. Exclusion criteria were obesity, dyslipidemia, diabetes mellitus, smoking and current use of any medication. All patients underwent 24-h ambulatory blood pressure monitoring and sampling of blood and urine. Antioxidant enzymes activity, reduced/oxidized glutathione ratio (GSH/GSSG), and lipid peroxidation (malondialdehyde) were determined in erythrocytes. Parameters measured in the plasma of test subjects were plasma antioxidant status, lipid peroxidation (8-isoprostane), plasma vitamin C and E, and the blood pressure modulators renin, aldosterone, endothelin-1 and homocysteine. Daytime systolic and diastolic blood pressures of hypertensives were negatively correlated with plasma antioxidant capacity (r=-0.46, p<0.009 and r=-0.48, p<0.007), plasma vitamin C levels (r=-0.53, p<0.003 and r=-0.44, p<0.02), erythrocyte activity of antioxidant enzymes, and erythrocyte GSH/GSSG ratio, with hypertensives showing higher levels of oxidative stress. Blood pressures showed a positive correlation with both plasma and urine 8-isoprostane. Neither plasma vitamin E nor the assessed blood pressure modulator levels showed significant differences between the groups or correlation with blood pressures. These findings demonstrate a strong association between blood pressure and some oxidative stress-related parameters and suggest a possible role of oxidative stress in the pathophysiology of essential hypertension. 相似文献
10.
Deep-freezing versus 4 degrees preservation of avascular osteocartilaginous shell allografts in rats 总被引:1,自引:0,他引:1
Osteocartilaginous allografts (distal femurs of rats) were stored at 4 degrees for six, 12, 24, and 48 hours and at -80 degrees for five days and then evaluated for viability of the bone and cartilage. Storage at 4 degrees for 12 or 24 hours had little effect on cartilage viability but decreased bone viability to 40% and 10% of controls, respectively. Storage at -80 degrees for five days resulted in nonviable bone in all cases but showed an either/or response of cartilage, with high viability in two cases and nonviability in the other eight cases. In a second set of experiments, femurs from rats were stored in situ at 4 degrees for 12 or 24 hours or were harvested and stored at -80 degrees for five days, after which they were transplanted into rats of a different strain. The antibody response to each set of femurs was measured at two, six, and 12 weeks after operation. The 4 degrees storage resulted in a moderately decreased immunogenicity, whereas the storage at -80 degrees resulted in significantly reduced immunogenicity. 相似文献