32 research outputs found
Predictors of HBeAg status and hepatitis B viraemia in HIV-infected patients with chronic hepatitis B in the HAART era in Brazil
<p>Abstract</p> <p>Background</p> <p>HBV-HIV co-infection is associated with an increased liver-related morbidity and mortality. However, little is known about the natural history of chronic hepatitis B in HIV-infected individuals under highly active antiretroviral therapy (HAART) receiving at least one of the two drugs that also affect HBV (TDF and LAM). Information about HBeAg status and HBV viremia in HIV/HBV co-infected patients is scarce. The objective of this study was to search for clinical and virological variables associated with HBeAg status and HBV viremia in patients of an HIV/HBV co-infected cohort.</p> <p>Methods</p> <p>A retrospective cross-sectional study was performed, of HBsAg-positive HIV-infected patients in treatment between 1994 and 2007 in two AIDS outpatient clinics located in the SĂŁo Paulo metropolitan area, Brazil. The baseline data were age, sex, CD4 T+ cell count, ALT level, HIV and HBV viral load, HBV genotype, and duration of antiretroviral use. The variables associated to HBeAg status and HBV viremia were assessed using logistic regression.</p> <p>Results</p> <p>A total of 86 HBsAg patients were included in the study. Of these, 48 (56%) were using combination therapy that included lamivudine (LAM) and tenofovir (TDF), 31 (36%) were using LAM monotherapy, and 7 patients had no previous use of either one. Duration of use of TDF and LAM varied from 4 to 21 and 7 to 144 months, respectively. A total of 42 (48. 9%) patients were HBeAg positive and 44 (51. 1%) were HBeAg negative. The multivariate analysis revealed that the use of TDF for longer than 12 months was associated with undetectable HBV DNA viral load (serum HBV DNA level < 60 UI/ml) (<it>p </it>= 0. 047). HBeAg positivity was associated with HBV DNA > 60 UI/ml (p = 0. 001) and ALT levels above normality (<it>p </it>= 0. 038).</p> <p>Conclusion</p> <p>Prolonged use of TDF containing HAART is associated with undetectable HBV DNA viral load. HBeAg positivity is associated with HBV viremia and increased ALT levels.</p
Sensores ópticos com detecção no infravermelho próximo e médio Near and mid infrared optical sensors
<abstract language="eng">Optical chemical sensors with detection in the near and mid infrared region are reviewed. Fundamental concepts of infrared spectroscopy and optical chemical sensors are briefly described, before presenting some aspects on optical chemical sensors, such as synthesis of NIR and IR reagents, preparation of new materials as well as application in determinations of species of biological, industrial and environmental importance
Evaluation of a PVC sensing phase for determination of chlorinated hydrocarbons in water by mid-infrared spectroscopy
In this work, mid-infrared spectroscopy has been employed to investigate the effect of amount (25 or 40%) and type of plasticiser (di-2-ethylhexyl sebacate (DOS), di-2-ethylhexyl phthalate (DOP) and 2-nitrophenyl octyl ether (NPOE)) on the analytical response of a poly(vinylchloride) (PVC) sensing phase for the determination of the chlorinated hydrocarbons (chlorobenzene (ClB), trichloroethylene (TCE) and trichlorobenzene (TCB)) in water. It was observed that films with 40% of plasticiser provided higher sensitivity and lower limits of detection than those with 25%, although the later films are easier to handle. A similar behaviour was also observed for sensing phases prepared with the plasticisers NPOE and DOS. By employing a DOS-based PVC sensing phase and extraction time of 60 min, limits of detection of 0.3, 0.6, and 0.5 mg L-1 were obtained for chlorobenzene, trichloroethylene and trichlorobenzene, respectively.Neste trabalho, a espectroscopia no infravermelho mĂ©dio foi utilizada para investigar o efeito da quantidade (25 ou 40%) e do tipo de plastificante (di-2-etilhexil ftalato (DOP), di-2-etilhexil sebacato (DOS) e 2-nitrofenil octil Ă©ter (NPOE)) na resposta analĂtica de uma fase sensora de poli(cloreto de vinila) (PVC) para a determinação de hidrocarbonetos clorados (clorobenzeno (ClB), tricloroetileno (TCE) e triclorobenzeno(TCB)) em ĂĄgua. Foi observado que os filmes com 40% de plastificante geraram maior sensibilidade e menores limites de detecção que aqueles preparados com 25%, embora esses Ășltimos sejam de manipulação mais fĂĄcil. Um comportamento similar foi tambĂ©m observado para fases sensoras preparadas com os plastificantes NPOE e DOS. Com o uso da fase sensora de PVC-DOS e um tempo de extração de 60 min, foram obtidos limites de detecção de 0,3, 0,6 e 0,5 mg L-1 para clorobenzeno, tricloroetileno e triclorobenzeno, respectivamente.14701477Fundação de Amparo Ă Pesquisa do Estado de SĂŁo Paulo (FAPESP)Conselho Nacional de Desenvolvimento CientĂfico e TecnolĂłgico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de NĂvel Superior (CAPES