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991.
M Ciccozzi M Equestre A Costantino N Marascio A Quirino A Lo Presti E Cella R Bruni MC Liberto A Focà G Pisani G Zehender AR Ciccaglione 《Journal of medical virology》2012,84(10):1613-1619
Hepatitis C Virus (HCV) genotype 4 predominates in Middle East and Central Africa countries. Recently, it has become also prevalent in Southern European countries where it is thought to have been introduced through immigration and the movement of intravenous drug users. In Italy, the prevalence of genotype 4 is particularly high (4.5%) in Southern regions, such as Calabria, and reaches values of 8.4% in specific areas where there appears to be endemic circulation of this genotype. In the present study, the phylogeny of HCV subtype 4d isolated from 19 Italian patients in Calabria was investigated by analysing a fragment of the NS5B viral genomic region. A Bayesian coalescent‐based framework was used to estimate origin and spread of the HCV 4d in this area. The mean evolutionary rate HCV 4d NS5B sequences was estimated using a dataset of sequences sampled at known times and a relaxed clock constant model that best fitted the data. By using a Bayesian coalescent method, the Italian 4d isolates collected in Calabria were found to share a common ancestor with reference 4d isolates whose origin was traced back to 1940s. The genotype 4d epidemic in Southern Italy was maintained in a steady non‐expanding phase until the late 1970s after that it grew exponentially up to 1990s probably sustained by the vast increase of unsafe blood transfusions and the spread of illicit intravenous drug users. J. Med. Virol. 84:1613–1619, 2012. © 2012 Wiley Periodicals, Inc. 相似文献
992.
Multicenter evaluation of a sequence-based protocol for subtyping shiga toxins and standardizing stx nomenclature 总被引:1,自引:0,他引:1
Scheutz F Teel LD Beutin L Piérard D Buvens G Karch H Mellmann A Caprioli A Tozzoli R Morabito S Strockbine NA Melton-Celsa AR Sanchez M Persson S O'Brien AD 《Journal of clinical microbiology》2012,50(9):2951-2963
When Shiga toxin-producing Escherichia coli (STEC) strains emerged as agents of human disease, two types of toxin were identified: Shiga toxin type 1 (Stx1) (almost identical to Shiga toxin produced by Shigella dysenteriae type 1) and the immunologically distinct type 2 (Stx2). Subsequently, numerous STEC strains have been characterized that express toxins with variations in amino acid sequence, some of which confer unique biological properties. These variants were grouped within the Stx1 or Stx2 type and often assigned names to indicate that they were not identical in sequence or phenotype to the main Stx1 or Stx2 type. A lack of specificity or consistency in toxin nomenclature has led to much confusion in the characterization of STEC strains. Because serious outcomes of infection have been attributed to certain Stx subtypes and less so with others, we sought to better define the toxin subtypes within the main Stx1 and Stx2 types. We compared the levels of relatedness of 285 valid sequence variants of Stx1 and Stx2 and identified common sequences characteristic of each of three Stx/Stx1 and seven Stx2 subtypes. A novel, simple PCR subtyping method was developed, independently tested on a battery of 48 prototypic STEC strains, and improved at six clinical and research centers to test the reproducibility, sensitivity, and specificity of the PCR. Using a consistent schema for nomenclature of the Stx toxins and stx genes by phylogenetic sequence-based relatedness of the holotoxin proteins, we developed a typing approach that should obviate the need to bioassay each newly described toxin and that predicts important biological characteristics. 相似文献
993.
Rachel Grossman MD Debraj Mukherjee MD David C. Chang PhD Michael Purtell MD Michael Lim MD Henry Brem MD Alfredo Quiñones-Hinojosa MD 《Annals of surgical oncology》2011,18(2):521-528
Objective
Risks of brain surgery in elderly patients with brain metastases are not well defined. This study was designed to quantify the postoperative risk for these patients after brain surgery for metastatic disease to the brain.Methods
We performed a retrospective analysis of the Nationwide Inpatient Sample (1998–2005). Patients aged 65 years or older who underwent tumor resection of brain metastases were identified by ICD-9 coding. Primary outcome was inpatient death. Other outcomes included systemic postoperative complications, length of stay (LOS), and total charges.Results
A total of 4,907 patients (53.6% men) were identified. Mean age was 72.1 years. Mean Charlson comorbidity score was 7.8. Inpatient mortality was 4%. The most common adverse events were pulmonary complications (3.4%). Mean length of stay was 9.2 days. Mean total charges were $57,596.39. In multivariate analysis, patients up to age 80 years had no significantly greater odds of inpatient death, relative to their 65- to 69-year-old counterparts. Each 1-point increase in Charlson score was associated with 12% increased odds of death, 0.52 days increased LOS, and $1,710.61 higher hospital charges. Postoperative pulmonary complications, stroke, or thromboembolic events increased LOS and total charges by up to 9.6 days and $57,664.42, respectively. These associations were statistically significant (P < 0.05).Conclusions
Surgical resection of brain metastases among the elderly up to the ninth decade of life is feasible. Age older than 80 years and higher Charlson comorbidity scores were found to be important prognostic factors for inpatient outcome. Incorporating these factors into preoperative decision making may help to select appropriately those elderly candidates for neurosurgical intervention. 相似文献994.
Alfredo De Diego Damiá Julio Cortijo Gimeno M. José Selma Ferrer Montserral León Fabregas Patricia Almudever Folch Javier Milara Paya 《Archivos de bronconeumologia》2011,47(9):447-453
IntroductionCigarette smoke is the main cause of inflammation in COPD. The mechanisms that differentiate smokers who develop COPD are diverse. In this study, we analyzed the presence of cytokines in the respiratory secretions of smokers with or without COPD and the secretory properties of the differentiated bronchial epithelium obtained from the individuals themselves after exposure to tobacco smoke.Material and methodsTwenty-seven smokers were studied, 12 of whom had COPD that had not been previously treated with steroids. In 11, samples were obtained by means of induced sputum, and the remaining samples were collected from bronchial aspiration after bronchoscopy. Concentrations of IL8, IL13, and TNFα in the supernatant were determined. The results obtained were compared between individuals with and without COPD, and we studied their relationship with the severity of COPD as expressed by the degree of obstruction, dyspnea, presence of hypersecretion and intensity of smoking. Bronchial epithelial cell cultures were obtained by air–liquid interface in 4 smokers. The samples were exposed to increasing concentrations of cigarette smoke (5%–20%) and the epithelial mRNA expressions of Muc5AC, IL8, and TNFα were determined.ResultsCOPD patients had significantly higher values of IL8 than healthy smokers (41 [22] pM vs 21 [12] pM). The values of IL8 correlated significantly with the severity of the obstruction (r=0.6; P<.05), dyspnea (r=0.45; P<.05) and the presence of hypersecretion. There was no relationship between cytokines and the intensity or duration of the tobacco habit. Cigarette smoke produced a dose-dependent increase in the expression of RNAm for Muc5AC, IL8, and TNFα.ConclusionsThere are differences in cytokine production (fundamentally IL8) between smokers and smokers with COPD which could be explained by the direct action of cigarette smoke on epithelial cells. 相似文献
995.
996.
997.
Jennifer J. Hunter Benjamin Masella Alfredo Dubra Robin Sharma Lu Yin William H. Merigan Grazyna Palczewska Krzysztof Palczewski David R. Williams 《Biomedical optics express》2011,2(1):139-148
In vivo two-photon imaging through the pupil of the primate eye has the potential to become a useful tool for functional imaging of the retina. Two-photon excited fluorescence images of the macaque cone mosaic were obtained using a fluorescence adaptive optics scanning laser ophthalmoscope, overcoming the challenges of a low numerical aperture, imperfect optics of the eye, high required light levels, and eye motion. Although the specific fluorophores are as yet unknown, strong in vivo intrinsic fluorescence allowed images of the cone mosaic. Imaging intact ex vivo retina revealed that the strongest two-photon excited fluorescence signal comes from the cone inner segments. The fluorescence response increased following light stimulation, which could provide a functional measure of the effects of light on photoreceptors.OCIS codes: (010.1080) adaptive optics, (330.4460) Ophthalmic optics and devices, (330.5310) Vision – photoreceptors, (330.7327) Visual optics, ophthalmic instrumentation 相似文献
998.
Parafoveal function is important for daily visual tasks such as reading. Here the variability in cone density along the four cardinal meridians in parafoveal regions of the retina was investigated in vivo using an adaptive optics fundus camera. Ten healthy normal trichromatic individuals were included in the study. There were significant differences in cone density between individuals at all four tested eccentricities (0.5, 1, 2 and 3°) and meridians. Cone density ranged from 34,900 to 63,000 cones/mm(2) at 1° horizontally, and from 31,600 to 60,700 at 1° vertically. The results were consistent with those of Curcio et al. (1990), although between-individual variability is greater than previously reported in the parafovea from 1 to 3.2°. 相似文献
999.
1000.
García-Kutzbach A Montenegro A Iraheta I Bará C Saénz R 《The American journal of the medical sciences》2011,341(4):295-297
The authors reviewed retrospectively a cohort of 233 spondyloarthropathy patients observed in 2 centers in Guatemala City, Guatemala, and in hospitals in San Salvador, El Salvador, and San Jose, Costa Rica. Guatemalan patients were either from the clinic of Guatemalan Association against Rheumatic Diseases (n = 105) or from the private clinic of AGK (n = 78). El Salvador patients (n = 17) were from Hospital Instituto Salvadoreño del Seguro Social, and Costa Rican patients (n = 33) were from Hospital Calderon Guardia, San Jose, Costa Rica. Except for the Costa Rican data, which were published in 2007, the patients’ medical records were analyzed using standardized questionnaires. Prevalence of spondyloarthropathy was slightly higher in females than males (57% versus 43%, respectively). The median age was 47.5 years. Most of our patients were diagnosed with reactive arthritis or undifferentiated arthritis (47% and 33%, respectively); 10% of patients had ankylosing spondylitis and 9% psoriatic arthritis. 相似文献