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201.
Angela RI Meyrelles Juliana D Siqueira Pamela P dos Santos Cristina B Hofer Ronir R Luiz Héctor N Seuánez Gutemberg Almeida Marcelo A Soares Esmeralda A Soares Elizabeth S Machado 《Memórias do Instituto Oswaldo Cruz》2016,111(2):120-127
This study investigated the rate of human papillomavirus (HPV) persistence,
associated risk factors, and predictors of cytological alteration outcomes in a
cohort of human immunodeficiency virus-infected pregnant women over an 18-month
period. HPV was typed through L1 gene sequencing in cervical smears
collected during gestation and at 12 months after delivery. Outcomes were defined as
nonpersistence (clearance of the HPV in the 2nd sample), re-infection (detection of
different types of HPV in the 2 samples), and type-specific HPV persistence (the same
HPV type found in both samples). An unfavourable cytological outcome was considered
when the second exam showed progression to squamous intraepithelial lesion or high
squamous intraepithelial lesion. Ninety patients were studied. HPV DNA persistence
occurred in 50% of the cases composed of type-specific persistence (30%) or
re-infection (20%). A low CD4+T-cell count at entry was a risk factor for
type-specific, re-infection, or HPV DNA persistence. The odds ratio (OR) was almost
three times higher in the type-specific group when compared with the re-infection
group (OR = 2.8; 95% confidence interval: 0.43-22.79). Our findings show that
bonafide (type-specific) HPV persistence is a stronger predictor for the development
of cytological abnormalities, highlighting the need for HPV typing as opposed to HPV
DNA testing in the clinical setting. 相似文献
202.
Mass spectrometry has been used to provide insights into the mechanism of inhibition of cysteine proteases by a hydroxylamine derivative, CBZ-Phe-Gly-NH-O-CO-(2,4,6-Me3)Ph. An oxidized form of papain resulting from the incubation of the enzyme with the peptidyl hydroxamate in the absence of a reducing agent has been identified as a sulfinic acid. The presence of a covalent enzyme-inhibitor complex of molecular mass consistent with a sulfenamide adduct of papain could also be detected by this method. Implications on the mechanism of inactivation of cysteine proteases by peptidyl hydroxamates are discussed. 相似文献
203.
Current research on the effects of gonadal steroids on the brain and spinal cord indicates that these agents have profound trophic effects on many aspects of neuronal functioning, including cell survival, growth and metabolism, elaboration of processes, synaptogenesis, and neurotransmission (Jones et al., 1985; Luine, 1985; Nordeen et al., 1985; Matsumoto et al., 1988a,b; Gould et al., 1990). Since many of the aspects of normal neuronal functioning altered by gonadal steroids are affected by injury to the nervous system, we initiated a series of experiments designed to exploit the trophic capabilities of steroids as therapeutic agents in neuronal injury and repair (Kujawa et al., 1989, 1991; Kujawa and Jones, 1990). Three steroid-sensitive model systems were used for these studies: the hamster facial motoneuron, the rat sciatic motoneuron, and the hamster rubrospinal motoneuron. The results of our initial series of experiments suggest that androgens, and possibly estrogens, act either directly or indirectly on the injured motoneuron and enhance elements of the neuronal reparative response that are critical to successful recovery of function. Recently, we discovered that gonadal steroids may also modulate the central glia response to nerve damage. In this review, a summary of our data identifying a therapeutic role for androgens in enhancing the reparative response of motoneurons to injury is presented. This is followed by a discussion of the effects of androgens on the glial response to injury. 相似文献