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111.
Focà E Motta D Pollara C Brianese N Gotti D Albini L Quiros-Roldan E Torti C Manca N 《The new microbiologica》2012,35(2):227-231
Our objective was to explore whether positive human cytomegalovirus (HCMV) DNAemia at baseline impaired CD4+ T-cell increase after 1 year of HAART. A sub-study of a randomized clinical trial in selected patients with <200 cell/mm CD4+ at baseline was conducted. Six out of 30 patients had detectable HCMV DNAemia at baseline, all reaching HCMV suppression at week 52 after HAART (only 1 of them was treated with valgancyclovir). No significant differences were found between patients with detectable or undetectable HCMV DNAemia in terms of CD4+ T-cell increase and HIV RNA response to HAART. Although some data may favor HCVM pre-emptive therapy to decrease immune activation, our results do not indicate that this practice may increase CD4+ T-cell count after HAART. At the same time, HAART proved effective in reducing HCMV DNAemia without the need for a specific therapy. 相似文献
112.
Cavka M Janković I Sikanjić PR Ticinović N Rados S Ivanac G Brkljacić B 《Collegium antropologicum》2010,34(3):797-802
The aim of the study was to analyze possible human skeletal remains within the wrappings of a mummy from the Archaeological Museum, Zagreb, Croatia through the use of the multidetector CT (MDCT) technology. Plain X-ray films and MDCT images of the mummy were taken in both frontal and lateral views. In a single volumetric acquisition of the whole body by MDCT 0.75 mm axial slices were obtained and combined with sagittal and coronal reformatting and three-dimensional (3D) reconstruction. Sex and age was assessed visually using standard anthropological methods. The results suggest that the mummy was of an adult female, most likely over 40 years of age at death. Pathologies observed included degenerative changes on the vertebral column and healed fractures of the lower right arm. Damage of the ethmoid bone at the roof of the nasal cavity was most likely caused by mortuary brain removal practice. Remnants of a resin and an unusual object were found inside the cranial cavity. An elongated metal object and additional three metal "belts" can be seen on the lower portion of the body. All internal organs were removed and thoracic and abdominal cavities were filled with various substances, most likely mud and pieces of linen cloth. Our results show that the MDCT is a very useful technique for assessing the human remains in archeological samples, especially in comparison to the use of plain film (X-ray), where important details are obscured and 3D imaging impossible. 相似文献
113.
Pollara CP Corbellini S Chiappini S Sandrini S De Tomasi D Bonfanti C Manca N 《The new microbiologica》2011,34(2):165-171
Infection by polyomavirus BK (BKV) is an emerging problem in the clinical management of renal transplant patients because it is responsible for nephropathy and consequently can cause loss of the transplanted organ (BKV associated nephropathy, BKVAN). Aim of this study was to evaluate the use of blood viral load measurement as a screening tool for diagnosis of BKV infection and to identify a threshold value for the management of patients. A total of 75 kidney transplant patients, corresponding to 338 consecutive plasma samples, were analyzed by an automatic system for nucleic acid extraction and quantitative real-time polymerase chain reaction (PCR) for detection of BKV. BKV was detected in 170 samples (26 patients) with a median viral load of 4.1 log10 copies/mL; among these 26 patients, seven (34.7%) were found to have BKVAN on allograft biopsy together with a median viral load of 5 log10 copies/mL. The ROC curve analysis identified a viral load equal to 4.1 log10 copies/mL as the best discriminant cut-off value to predict the disease and to identify patients at risk of developing BKVAN. 相似文献
114.
Carrie V. Breton Wendy J. Mack Jin Yao Kiros Berhane Milena Amadeus Fred Lurmann Frank Gilliland Rob McConnell Howard N. Hodis Nino Künzli Ed Avol 《PloS one》2016,11(3)
Exposure to ambient air pollutants increases risk for adverse cardiovascular health outcomes in adults. We aimed to evaluate the contribution of prenatal air pollutant exposure to cardiovascular health, which has not been thoroughly evaluated. The Testing Responses on Youth (TROY) study consists of 768 college students recruited from the University of Southern California in 2007–2009. Participants attended one study visit during which blood pressure, heart rate and carotid artery arterial stiffness (CAS) and carotid artery intima-media thickness (CIMT) were assessed. Prenatal residential addresses were geocoded and used to assign prenatal and postnatal air pollutant exposure estimates using the U.S. Environmental Protection Agency’s Air Quality System (AQS) database. The associations between CAS, CIMT and air pollutants were assessed using linear regression analysis. Prenatal PM10 and PM2.5 exposures were associated with increased CAS. For example, a 2 SD increase in prenatal PM2.5 was associated with CAS indices, including a 5% increase (β = 1.05, 95% CI 1.00–1.10) in carotid stiffness index beta, a 5% increase (β = 1.05, 95% CI 1.01–1.10) in Young’s elastic modulus and a 5% decrease (β = 0.95, 95% CI 0.91–0.99) in distensibility. Mutually adjusted models of pre- and postnatal PM2.5 further suggested the prenatal exposure was most relevant exposure period for CAS. No associations were observed for CIMT. In conclusion, prenatal exposure to elevated air pollutants may increase carotid arterial stiffness in a young adult population of college students. Efforts aimed at limiting prenatal exposures are important public health goals. 相似文献
115.
Amodio R Zarcone M Cusimano R Campisi I Dolcemascolo C Traina A Agostara B Romano N 《Omics : a journal of integrative biology》2011,15(6):363-367
The development of new therapeutic strategies, such as monoclonal antibodies directed against human epidermal growth factor receptor-2 (HER2), has offered new hopes for women with early breast cancer whose tumors overexpress HER2. We retrospectively analyzed the population-based data of Breast Cancer Registry of Palermo in 2004-2006, and selected 1401 invasive breast cancer cases, nonmetastatic at diagnosis, having HER2/neu oncogene expression determined. We have correlated this information to age, tumor stage at diagnosis (TNM), nodal involvement, and receptor status (ER and PgR). Survival analysis was conducted dividing the patients in two different groups according to date of diagnosis: one group diagnosed in 2004 and a second group in 2005-2006. In the 460 cases of 2004, nodal involvement, receptor status, age at diagnosis and TNM maintained a strong predictive value (p?0.0001). In this group of patients, overall survival was significantly different according to the HER2 expression levels (p?=?0.001). In the second group of patients (941 incident cases in 2005-2006) there was a statistically significant survival difference comparing patients with high levels of HER2 expression treated with trastuzumab versus those untreated (p?=?0.006). Our data show that elevated levels of HER2 are a negative prognostic factor. In addition, patients overexpressing HER2 show a significant increase of overall survival when treated with trastuzumab. 相似文献
116.
117.
Daniel Restrepo-Montoya Luis F Nino Manuel E Patarroyo Manuel A Patarroyo 《BMC bioinformatics》2011,12(1):21
Background
Most predictive methods currently available for the identification of protein secretion mechanisms have focused on classically secreted proteins. In fact, only two methods have been reported for predicting non-classically secreted proteins of Gram-positive bacteria. This study describes the implementation of a sequence-based classifier, denoted as NClassG+, for identifying non-classically secreted Gram-positive bacterial proteins. 相似文献118.
Nino Lomtadze Lali Kupreishvili Archil Salakaia Sergo Vashakidze Lali Sharvadze Russell R. Kempker Matthew J. Magee Carlos del Rio Henry M. Blumberg 《PloS one》2013,8(12)
Background
The country of Georgia has a high prevalence of tuberculosis (TB) and hepatitis C virus (HCV) infection.Purpose
To determine whether HCV co-infection increases the risk of incident drug-induced hepatitis among patients on first-line anti-TB drug therapy.Methods
Prospective cohort study; HCV serology was obtained on all study subjects at the time of TB diagnosis; hepatic enzyme tests (serum alanine aminotransferase [ALT] activity) were obtained at baseline and monthly during treatment.Results
Among 326 study patients with culture-confirmed TB, 68 (21%) were HCV co-infected, 14 (4.3%) had chronic hepatitis B virus (HBV) infection (hepatitis B virus surface antigen positive [HBsAg+]), and 6 (1.8%) were HIV co-infected. Overall, 19% of TB patients developed mild to moderate incident hepatotoxicity. In multi-variable analysis, HCV co-infection (adjusted Hazards Ratio [aHR]=3.2, 95% CI=1.6-6.5) was found to be an independent risk factor for incident anti-TB drug-induced hepatotoxicity. Survival analysis showed that HCV co-infected patients developed hepatitis more quickly compared to HCV seronegative patients with TB.Conclusion
A high prevalence of HCV co-infection was found among patients with TB in Georgia. Drug-induced hepatotoxicity was significantly associated with HCV co-infection but severe drug-induced hepatotoxicity (WHO grade III or IV) was rare. 相似文献119.
Malate synthase catalyzes the Claisen-like condensation of acetyl-coenzyme A (AcCoA) and glyoxylate in the glyoxylate shunt of the citric acid cycle. The Mycobacterium tuberculosis malate synthase G gene, glcB, was cloned, and the N-terminal His(6)-tagged 80 kDa protein was expressed in soluble form and purified by metal affinity chromatography. A chromogenic 4,4'-dithiodipyridine assay did not yield linear kinetics, but the generation of an active site-directed mutant, C619S, gave an active enzyme and linear kinetics. The resulting mutant exhibited kinetics comparable to those of the wild type and was used for the full kinetic analysis. Initial velocity studies were intersecting, suggesting a sequential mechanism, which was confirmed by product and dead-end inhibition. The inhibition studies delineated the ordered binding of glyoxylate followed by AcCoA and the ordered release of CoA followed by malate. The pH dependencies of k(cat) and k(cat)/K(gly) are both bell-shaped, and catalysis depends on a general base (pK = 5.3) and a general acid (pK = 9.2). Primary kinetic isotope effects determined using [C(2)H(3)-methyl]acetyl-CoA suggested that proton removal and carbon-carbon bond formation were partially rate-limiting. Solvent kinetic isotope effects on k(cat) suggested the hydrolysis of the malyl-CoA intermediate was also partially rate-limiting. Multiple kinetic isotope effects, utilizing D(2)O and [C(2)H(3)-methyl]acetyl-CoA, confirmed a stepwise mechanism in which the step exhibiting primary kinetic isotope effects precedes the step exhibiting the solvent isotope effects. We combined the kinetic data and the pH dependence of the kinetic parameters with existing structural and mutagenesis data to propose a chemical mechanism for malate synthase from M. tuberculosis. 相似文献
120.
Martin Adam Medea Imboden Eva Boes Emmanuel Schaffner Nino Künzli Harish Chandra Phuleria Florian Kronenberg Jean-Michel Gaspoz David Carballo Nicole Probst-Hensch 《PloS one》2014,9(8)