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91.
92.
Yebra G de Mulder M Martín L Rodríguez C Labarga P Viciana I Berenguer J Alemán MR Pineda JA García F Holguín A;Cohort of the Spanish AIDS Research Network 《Journal of clinical microbiology》2012,50(2):407-413
HIV-1 group M is classified into 9 subtypes, as well as recombinants favored by coinfection and superinfection events with different variants. Although HIV-1 subtype B is predominant in Europe, intersubtype recombinants are increasing in prevalence and complexity. In this study, phylogenetic analyses of pol sequences were performed to detect the HIV-1 circulating and unique recombinant forms (CRFs and URFs, respectively) in a Spanish cohort of antiretroviral treatment-naïve HIV-infected patients included in the Research Network on HIV/AIDS (CoRIS). Bootscanning and other methods were used to define complex recombinants not assigned to any subtype or CRF. A total of 670 available HIV-1 pol sequences from different patients were collected, of which 588 (87.8%) were assigned to HIV-1 subtype B and 82 (12.2%) to HIV-1 non-B variants. Recombinants caused the majority (71.9%) of HIV-1 non-B infections and were found in 8.8% of CoRIS patients. Eleven URFs (accounting for 13.4% of HIV-1 non-B infections), presenting complex mosaic patterns, were detected. Among them, 10 harbored subtype B fragments. Four of the 11 URFs were found in Spanish natives. A cluster of three B/CRF02_AG recombinants was detected. We conclude that complex variants, including unique recombinant forms, are being introduced into Spain through both immigrants and natives. An increase in the frequency of mosaic viruses, reflecting the increasing heterogeneity of the HIV epidemic in our country, is expected. 相似文献
93.
Goñi N Moratorio G Ramas V Coppola L Chiparelli H Cristina J 《Archives of virology》2011,156(1):87-94
The first influenza pandemic of this century was declared in April of 2009, with the emergence of a novel H1N1 influenza A
virus strain (H1N1pdm). Understanding the evolution of H1N1pdm strains within the South American region is essential for studying
global diversification, emergence and resistance, as well as determining vaccine efficacy. In order to gain insight into these
matters, phylogenetic analysis was performed using 29 hemagglutinin (HA) gene sequences from H1N1pdm strains isolated in South
America. The results of these studies revealed that clade 7 was the dominant H1N1pdm lineage in South America. None of the
strains isolated in South America clustered together with the 2010 H1 vaccine strain. Amino acid substitutions P100S, S220T
and I338V were found in almost all HAs of South American H1N1pdm strains. 相似文献
94.
Stefanie Kreutmair Susanne Unger Nicolás Gonzalo Núñez Florian Ingelfinger Chiara Alberti Donatella De Feo Sinduya Krishnarajah Manuel Kauffmann Ekaterina Friebel Sepideh Babaei Benjamin Gaborit Mirjam Lutz Nicole Puertas Jurado Nisar P. Malek Siri Goepel Peter Rosenberger Helene A. Häberle Ikram Ayoub Burkhard Becher 《Immunity》2021,54(7):1578-1593.e5
95.
Sorlózano A Gutiérrez J Romero JM de Dios Luna J Damas M Piédrola G 《Journal of basic microbiology》2007,47(5):413-416
Twelve beta-lactam and non-beta-lactam antibiotics were evaluated against 115 clinical isolates of extended-spectrum beta-lactamase-producing (ESBLs) Escherichia coli using a broth microdilution test in accordance with the CLSI guidelines. Susceptibility was 100% with imipenem, ertapenem and amikacin, 95.7% with piperacillin-tazobactam, 91.3% with cefoxitin, 87% with tobramycin, 81.7% with amoxicillin-clavulanate, 80% with cefepime, 67.8% with ceftazidime, 27.8% with ciprofloxacin, 27% with levofloxacin and 13% with ceftriaxone. Ertapenem was the antibiotic with the lowest minimum inhibitory concentrations (MICs) for all isolates. There were no clinically relevant differences in the activity of the antibiotics in the presence of CTX-M-9 or SHV enzymes. 相似文献
96.
Keila Correia Alcântara Monica Nogueira Guarda Reis Ludimila Paula Vaz Cardoso Gonzalo Bello Mariane Martins Araújo Stefani 《Journal of medical virology》2013,85(3):396-404
The molecular epidemiology of HIV‐1 in Brazil is complex and heterogeneous because several subtypes co‐circulate with some important regional differences. This study evaluated HIV‐1 subtypes amongst pregnant women living in the metropolitan area and in the interior cities from central western Brazil. From June 2008 to June 2010, 86.9% of confirmed cases of HIV‐1 infection amongst pregnant women (172 out of 198 cases) were recruited in Goiania/Goias state. The HIV‐1 pol gene was sequenced after nested‐PCR. HIV‐1 subtypes were assigned by REGA, phylogenetic, and bootscan analyses. The median age of participants was 26 years (15–41 years range); 58.7% of participants were diagnosed during prenatal care and 51.7% of participants came from >50 interior cities within Goias state. Amongst the 131 HIV‐1 pol sequences, 64.9% were subtype B, 13.0% were BF1 recombinant, 11.4% were subtype C, 7.6% were subtype F1, and 2.3% were BC recombinant. According to the HIV‐1 diagnosis date (1994–2010), a significant increase in subtype C and a decrease of BF1 mosaics were observed over time. All subtype C patients lived in interior cities where the highest prevalence of subtype C outside southern Brazil was observed (18.4%). Phylogenetic analysis revealed multiple independent introductions of the Brazilian subtype C clade from the southern/southeastern regions of Brazil. The HIV‐1 epidemic in women from central western Brazil infected by the heterosexual route is characterized by an unexpectedly high prevalence of subtype C viruses highly related to those circulating in southern/southeastern Brazil. These findings highlight the importance of molecular surveillance programs outside large metropolitan regions in Brazil. J. Med. Virol. 85:396–404, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
97.
Ofelia Dolores Hernández Ángel José Gutiérrez Dailos González‐Weller Gonzalo Lozano Enrique García Melón Carmen Rubio Arturo Hardisson 《Environmental toxicology》2010,25(3):227-233
This document shows the results obtained from a study on the concentration of toxic heavy metals in the internal tissue and exoskeleton of sea urchins, collected from their natural habitat. The levels of lead and cadmium were measured by Graphite Furnace Atomic Absorption Spectrometry. The mean concentrations of lead and cadmium in the internal tissue were 304.04 and 260.54 μg/kg respectively, whereas in the shell they were 185.02 and 142.48 μg/kg. We also performed a statistical analysis of the differences in the distribution of metals between their exoskeleton and their internal content, a correlation study of the metal content in internal tissue and shell and sampling areas, and a correlation study between the metal content and sample size. Since the sea urchin Diadema antillarum presents a wide range of variation in metal content, this study suggests that this species is an excellent bioindicator of heavy metal contamination. © 2009 Wiley Periodicals, Inc. Environ Toxicol, 2010. 相似文献
98.
David P. Al-Adra Laura Hammel John Roberts E. Steve Woodle Deborah Levine Didier Mandelbrot Elizabeth Verna Jayme Locke Jonathan D'Cunha Maryjane Farr Deirdre Sawinski Piyush K. Agarwal Jennifer Plichta Sandhya Pruthi Deborah Farr Richard Carvajal John Walker Fiona Zwald Thomas Habermann Morie Gertz Philip Bierman Don S. Dizon Carrie Langstraat Talal Al-Qaoud Scott Eggener John P. Richgels George J. Chang Cristina Geltzeiler Gonzalo Sapisochin Rocco Ricciardi Alexander S. Krupnick Cassie Kennedy Nisha Mohindra David P. Foley Kymberly D. Watt 《American journal of transplantation》2021,21(2):460-474
Patients undergoing evaluation for solid organ transplantation (SOT) often have a history of malignancy. Although the cancer has been treated in these patients, the benefits of transplantation need to be balanced against the risk of tumor recurrence, especially in the setting of immunosuppression. Prior guidelines of when to transplant patients with a prior treated malignancy do not take in to account current staging, disease biology, or advances in cancer treatments. To develop contemporary recommendations, the American Society of Transplantation held a consensus workshop to perform a comprehensive review of current literature regarding cancer therapies, cancer stage-specific prognosis, the kinetics of cancer recurrence, and the limited data on the effects of immunosuppression on cancer-specific outcomes. This document contains prognosis based on contemporary treatment and transplant recommendations for breast, colorectal, anal, urological, gynecological, and nonsmall cell lung cancers. This conference and consensus documents aim to provide recommendations to assist in the evaluation of patients for SOT given a history of a pretransplant malignancy. 相似文献
99.
Gaca JG Appel JZ Lukes JG Gonzalez-Stawinski GV Lesher A Palestrant D Logan JS Love SD Holzknecht ZE Platt JL Parker W Davis RD 《Transplantation》2006,81(12):1686-1694
BACKGROUND: In contrast to renal or cardiac xenografts, the inhibition of complement using cobra venom factor (CVF) accelerates pulmonary xenograft failure. By activating C3/C5 convertase, CVF depletes complement while additionally generating C5a and other anaphylatoxins, to which pulmonary xenografts may be uniquely susceptible. The current study investigates the role of C5a in pulmonary xenograft failure in baboons. METHODS: Left orthotopic pulmonary xenografts using swine lungs expressing human CD46 were performed in baboons receiving: I) no other treatment (n=4), II) immunodepletion (n=5), and III) immunodepletion plus a single dose of mouse anti-human C5a monoclonal antibody (anti-C5a, 0.6 mg/kg administered intravenously) (n=3). The extent to which anti-C5a inhibits baboon C5a was assessed in vitro using a hemolytic reaction involving baboon serum and porcine red blood cells and by ELISA. RESULTS: Baboons in Group III exhibited significantly prolonged xenograft survival (mean=722+/-121 min, P=0.02) compared to baboons in Group I (mean=202+/-24 min) and Group II (mean=276+/-79 min). Furthermore, baboons in Groups I and II experienced pronounced hemodynamic compromise requiring inotropic support whereas those in Group III remained hemodynamically stable throughout experimentation without the need for additional pharmacologic intervention. CONCLUSIONS: These findings indicate that C5a exacerbates pulmonary xenograft injury and compromises recipient hemodynamic status. Moreover, blockade of anaphylatoxins, such as C5a, offers a promising approach for future investigations aimed at preventing pulmonary xenograft injury in baboons. 相似文献