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OBJECTIVE: To analyze the safety and effectiveness of abacavir, lamivudine, and zidovudine (ABC/3TC/ZDV) in antiretroviral therapy (ART)-naive HIV-infected patients. DESIGN: Retrospective observational cohort study. METHODS: We analyzed all consecutive ART-naive HIV-infected patients who initiated ABC/3TC/ZDV in 71 centers throughout Spain and had a clinical visit and laboratory data at least 16 weeks after initiating this regimen. We assessed safety, mortality, new AIDS-defining conditions (ADCs) and treatment failure, the latter defined by any of the following: (1) reduction in plasma HIV-1 viral load (pVL) <1 log during the first 12 weeks of ART, unless it was less than the lower limit of quantification (LOQ); (2) failure to achieve a pVL or = LOQ after achieving a pVL 相似文献   
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Vaccination generates a neutralizing immune response against SARS-CoV-2. The genomic surveillance is showing the emergence of variants with mutations in spike, the main target of neutralizing antibodies. To understand the impact of these variants, we report the neutralization potency against alpha, gamma, and D614G SARS-CoV-2 variants in 44 individuals that received two doses of CoronaVac vaccine, an inactivated SARS-CoV-2 vaccine. Plasma samples collected at 60 days after the second dose of CoronaVac were analyzed by the reduction of cytopathic effect in Vero E6 cells with the three infectious variants of SARS-CoV-2. Plasma showed lower neutralization with alpha (geometric mean titer [GMT] = 18.5) and gamma (GMT = 10.0) variants than with D614G (GMT = 75.1) variant. Efficient neutralization against the alpha and gamma variants was not detected in 31.8% and 59.1% of plasma, respectively. These findings suggest the alpha and gamma variants could escape from neutralization by antibodies elicited by vaccination. Robust genomic and biological surveillance of viral variants could help to develop effective strategies for the control of SARS-CoV-2.  相似文献   
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Factor VIII (FVIII), von Willebrand factor (vWF) and the ABO blood groups have been associated with thrombosis. The ABO locus has functional effects on vWF and FVIII levels and is genetically correlated with FVIII, vWF and thrombosis. We carried out a case-control study to assess the role of FVIII, vWF and ABO types on thrombotic risk. We analyzed 250 patients with venous thrombosis and 250 unrelated controls. FVIII, vWF and other factors related to thrombophilia were measured, ABO groups were analyzed by genotyping. FVIII and vWF were higher in non-O individuals. Group O was more frequent in the controls (44.3% v 23.3%; difference 21.1%; 95% CI: 13.0-29.3%) and Group A in patients (59.2% v. 41.5%; difference 17.7%, 95% CI: 9.1-26.4%). Individuals carrying the A1 allele had a higher risk of thrombosis (OR 2.6; 95% CI, 1.8-3.8). The risk attributed to vWF disappeared after adjusting for the ABO group. Patients with FVIII above the 90th percentile had a high thrombotic risk (adjusted OR 3.7; 95% CI, 2.1-6.5), and a high risk of recurrence (OR 2.3; 95% CI: 1.3-4.1). In conclusion, high FVIII levels and non-O blood groups, likely those with the A1 allele, are independent risk factors for venous thromboembolism and should be considered in evaluating of thrombophilia.  相似文献   
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The IIA binding site of human serum albumin (HSA) preferentially binds hydrophobic organic anions of medium size (e.g., aspirin, benzylpenicillin, warfarin, etc.) and bilirubin. This binding ability is particularly important for the distribution, metabolism, and efficacy of drugs. In addition, HSA can also covalently link to different IIA substrates owing to the presence of a highly reactive residue, Lys199, which is strategically located in the IIA site. Herein, we present results of three restrained molecular dynamics (MD) simulations of the IIA binding site on the HSA protein. From these simulations, we have determined the influence that the ionization state of the key residue, Lys199, and the nearby Lys195 has on the structure and dynamics of the IIA binding site. When Lys199 is neutral the computed average distances for the most significant interresidue contacts are in good agreement with those estimated from the X-ray coordinates. The analysis of the solvent structure and dynamics indicates that the basic form of Lys199 is likely connected to the acid form of Lys195 through a network of H-bonding water molecules with a donor --> acceptor character. The presence of these water bridges can be important for stabilizing the configuration of the IIA binding site and/or promoting a potential Lys195 --> Lys199 proton-transfer process. These results suggest that both lysine residues located in the IIA binding site of HSA, Lys195 and Lys199, could play a combined and comparable chemical role. Our simulations also give insight into the binding of bilirubin to HSA.  相似文献   
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LMNA mutations have been associated with familial or sporadic dilated cardiomyopathy (DC), with or without conduction system disease. We studied the LMNA gene in 67 consecutive patients with DC (18 had familial DC, 17 had possible familial DC, and 32 sporadic DC). From genomic DNA, coding regions of the LMNA gene were amplified by polymerase chain reaction, studied by single-strand conformation polymorphism, and cycle sequenced. Mutations were confirmed by restriction fragment length polymorphism. Two disease-causing mutations were found in families A and B. In family A, a novel R349L mutation was present in the mother and her identical twin daughters. They required cardiac transplantation at 36, 18, and 20 years of age. In family B, the R190W mutation was present in 2 cousins with DC and without conduction system disease (1 had cardiac transplantation at 45 years of age and 1 died suddenly at 46 years of age) and in 2 of their sons. The mothers of the 2 affected patients died due to cardiac causes in their 40s (1 died suddenly). One of the carriers fulfilled diagnostic criteria for isolated left ventricular noncompaction. Our data associated the R349L and R190W mutations in LMNA with severe forms of familial DC. LMNA mutations should be considered in the genetic screening of patients with familial DC without conduction system disease. Isolated left ventricular noncompaction may be part of the phenotypic spectrum of the laminopathies.  相似文献   
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Recent evidence suggests that nasal irrigation with hypertonic saline may be useful as an adjunctive treatment modality in the management of many sinonasal diseases. However, no previous studies have investigated the efficacy of this regimen in the prevention of seasonal allergic rhinitis-related symptoms in the pediatric patient. Twenty children with seasonal allergic rhinitis to Parietaria were enrolled in the study. Ten children were randomized to receive three-times daily nasal irrigation with hypertonic saline for the entire pollen season, which had lasted 6 weeks. Ten patients were allocated to receive no nasal irrigation and were used as controls. A mean daily rhinitis score based on the presence of nasal itching, rhinorrea, nasal obstruction and sneezing was calculated for each week of the pollen season. Moreover, patients were allowed to use oral antihistamines when required and the mean number of drug assumption per week was also calculated. In patients allocated to nasal irrigation, the mean daily rhinitis score was reduced during 5 weeks of the study period. This reduction was statistically significantly different in the 3th, 4th and 5th week of therapy. Moreover, a decreased consumption of oral antihistamines was observed in these patients. This effect became evident after the second week of treatment and resulted in statistically significant differences during the 3th, 4th and 6th week. This study supports the use of nasal irrigation with hypertonic saline in the pediatric patient with seasonal allergic rhinitis during the pollen season. This treatment was tolerable, inexpensive and effective.  相似文献   
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