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51.
Background: Strain-specific antibodies to human cytomegalovirus (HCMV) glycoproteins B and H (gB and gH) have been proposed as a potential diagnostic tool for identifying reinfection. We investigated genotype-specific IgG antibody responses in parallel with defining the gB and gH genotypes of the infecting viral strains. Methods: Subjects with primary (n = 20) or non-primary (n = 25) HCMV infection were studied. The seven gB (gB1-7) and two gH (gH1-2) genotypes were determined by real-time PCR and whole viral genome sequencing, and genotype-specific IgG antibodies were measured by a peptide-based enzyme-linked immunosorbent assay (ELISA). Results: Among subjects with primary infection, 73% (n = 8) infected by gB1-HCMV and 63% (n = 5) infected by gB2/3-HCMV had genotype-specific IgG antibodies to gB (gB2 and gB3 are similar in the region tested). Peptides from the rarer gB4-gB7 genotypes had nonspecific antibody responses. All subjects infected by gH1-HCMV and 86% (n = 6) infected by gH2-HCMV developed genotype-specific responses. Among women with non-primary infection, gB and gH genotype-specific IgG antibodies were detected in 40% (n = 10) and 80% (n = 20) of subjects, respectively. Conclusions: Peptide-based ELISA is capable of detecting primary genotype-specific IgG responses to HCMV gB and gH, and could be adopted for identifying reinfections. However, about half of the subjects did not have genotype-specific IgG antibodies to gB.  相似文献   
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Although considerable research has examined the influence of parent-adolescent relationships on the sexual health of adolescents, there is a great need for research to understand the influence of fathers on their children’s HIV sexual risk behavior, particularly in sub-Saharan Africa. We examined how the residence and the involvement of fathers are related to their children’s HIV sexual risk and alcohol consumption behaviors. A cross-sectional survey was completed by 175 sixth-grade adolescents in the Eastern Cape Province, South Africa. Analyses showed that adolescents living with their fathers had fewer sexual partners (B?=?? 0.606, SE?=?0.299, p?=?.043) and consumed alcohol less frequently (B?=?? 0.642, SE?=?0.294, p?=?.029). Adolescents who spent more quality days with their fathers in the past 30 days had fewer sexual partners (B?=?? 0.103, SE?=?0.039, p?=?.008) and had condomless sex less frequently (B?=?? 0.097, SE?=?0.047, p?=?0.041). It was also found that there were significant father-residence?×?child-gender interactions on sexual debut (B?=?1.132, SE?=?0.564, p?=?.045) and on frequency of condomless sex (B?=?? 2.140, SE?=?0.924, p?=?.021). These interactions indicate that boys living with their fathers were less likely to have had vaginal intercourse than girls and that girls living with their fathers were less likely to have unprotected sex than boys. This study highlights the importance of South African fathers’ roles in their adolescent children’s HIV sexual risk and alcohol drinking behaviors and the need to promote father-child relationships for adolescent health. The results suggest that health programs aiming to reduce South African adolescents’ HIV sexual risk behaviors and alcohol consumption consider strategies that target their fathers.

  相似文献   
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Background

The bilateral absence of the cortical N20 median-nerve somatosensory evoked potential (SSEP) is a strong predictor of poor outcome from coma. However, when N20s are present, accurate prognostication is challenging. Here, we investigated the potential for later SSEP components to help disambiguate outcome in these cases.

Methods

In a retrospective review of data from two intensive care units, the amplitudes and latencies of the N20, P25, and N35 components of 28 patients in coma were quantified and related to outcome at discharge from primary care (average 1-month post-injury). Only patients who had survived primary care were included in order to avoid self-fulfilling prophecies, and to focus outcome prediction on those patients with relatively present SSEPs.

Results

The amplitudes of the N20 and N35 components (averaged across hemispheres) significantly predicted the range of outcomes beyond death. Abnormal amplitudes of the N20 and N35—as derived from a healthy control group—were significantly associated with poor outcome. The relative latencies of the cortical components were not related to outcome.

Conclusions

While it is well documented that absent SSEPs are highly predictive of poor outcome, the current data indicate that the relative preservation (absolute amplitude) of “present” N20 and N35 SSEP components can also provide predictive value and thereby inform clinicians and families with decision-making in coma. Further prospective study will elucidate the relative contributions of etiology to the predictive power of these SSEP measures.  相似文献   
56.

Introduction

The diagnosis of microscopic lymph node metastasis in lung cancer is challenging despite the constant advances in tumor staging. The analysis of the methylation status of certain genes in lymph node samples could improve the diagnostic capability of conventional cyto-histological methods. The aim of this study was to demonstrate the feasibility of methylation studies using cytological lymph node samples.

Methods

Prospective study including 88 patients with a diagnosis or strong suspicion of non-small cell lung cancer, in which an echobronchoscopy was performed on mediastinal or hilar lymph nodes for diagnostic and/or staging. DNA was extracted from cytological lymph node samples and sodium bisulfite modification was performed. Methylation studies for p16/INK4a and SHOX2 were accomplished by MS-qPCR and pyrosequencing.

Results

The methodology used in our study yielded optimal/good DNA quality in 90% of the cases. No differences in DNA concentration were observed with respect to the lymph node biopsied and final diagnosis. Methylation analyses using MS-qPCR and pyrosequencing were not possible in a small number of samples mainly due to low DNA concentration, inadequate purity, fragmentation and/or degradation as a consequence of bisulfite conversion.

Conclusion

Methylation quantification using MS-qPCR and pyrosequencing of cytological lymph node samples obtained using echobronchoscopy is feasible if an appropriate DNA concentration is obtained, notably contributing to the identification of epigenetic biomarkers capable of improving decision-making for the benefit of potentially curable lung cancer patients.  相似文献   
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Objectives. We tested the efficacy of a sexual risk-reduction intervention for men in South Africa, where heterosexual exposure is the main mode of HIV transmission.Methods. Matched-pairs of neighborhoods in Eastern Cape Province, South Africa, were randomly selected and within pairs randomized to 1 of 2 interventions based on social cognitive theory and qualitative research: HIV/sexually transmitted infection (STI) risk-reduction, targeting condom use, or attention-matched control, targeting health issues unrelated to sexual risks. Sexually active men aged 18 to 45 years were eligible. The primary outcome was consistent condom use in the past 3 months.Results. Of 1181 participants, 1106 (93.6%) completed the 12-month follow-up. HIV and STI risk-reduction participants had higher odds of reporting consistent condom use (odds ratio [OR] = 1.32; 95% confidence interval [CI] = 1.03, 1.71) and condom use at last vaginal intercourse (OR = 1.40; 95% CI = 1.08, 1.82) than did attention-control participants, adjusting for baseline prevalence. No differences were observed on unprotected intercourse or multiple partnerships. Findings did not differ for sex with steady as opposed to casual partners.Conclusions. Behavioral interventions specifically targeting men can contribute to efforts to reduce sexual risk behaviors in South Africa.South Africa has more HIV cases than any other country, and like other sub-Saharan countries, has a predominantly heterosexual epidemic.1 In such an epidemic, men have an especially critical role to play: they are the ones who don male condoms, a particularly effective and available means of prevention, and thus control their use. They have, it has been argued, more power than women in relationships2–4 and are responsible for infecting women in many contexts, including forced intercourse and violence.3 Although calls for male responsibility in sexual behavior related to HIV and other sexually transmitted infections (STIs) have been made repeatedly,5–7 to our knowledge, only 1 study has evaluated an intervention created specifically for heterosexual men in South Africa.8 Men who received the gender-based-violence-and-HIV-risk-reduction intervention were more likely to report talking with a partner about condoms and using condoms consistently 1-month postintervention compared with men in an alcohol-and-HIV-risk-reduction control intervention.The present study evaluated an HIV/sexually transmitted infection (STI) risk-reduction intervention for South African men who have intercourse with women. We used a cluster-randomized design to reduce the potential for contamination between treatment arms that would be present if we were to randomize individuals. We randomized randomly selected neighborhoods (i.e., clusters) to a 3-session intervention based on social cognitive theory9 and extensive formative research10 and designed to reduce HIV/STI risk behavior or to a 3-session attention-control intervention designed to promote health by improving diet and physical activity. We hypothesized that the HIV/STI risk-reduction intervention would increase self-reported consistent condom use during vaginal intercourse in the postintervention period, the primary outcome, compared with the attention-control intervention, controlling for baseline condom use.  相似文献   
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Oral voriconazole is commonly used for treatment and prophylaxis of invasive fungal disease post‐LTx. Development of cutaneous SCC has been described in adult LTx recipients, although it is extremely rare in children. We describe two Caucasian children who developed cutaneous SCC beyond three yr post‐LTx. Both developed severe photosensitivity, actinic keratosis and required curative surgical excision of the cutaneous SCC lesions. Neither patient developed metastatic lesions nor had allograft dysfunction as a result of the SCC or the change in medical treatments. The effect of voriconazole on the development of malignant skin lesions is discussed and a recommendation on dermatologic surveillance, preventive measures against phototoxicity and early treatment of SCC are provided.  相似文献   
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