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51.
CD4 proliferative responses to the human immunodeficiency virus (HIV) type 1 (HIV-1) p24 (gag) antigen inversely correlate with the plasma viral load in HIV-infected subjects who control viral replication without antiretroviral therapy. Use of a single HIV-1 protein to assess CD4 proliferative responses may not reflect the global response to this pathogen. We compared the abilities of HIV p24 and gp120 antigens from two different vendors, an inactivated whole HIV-1 MN virion preparation and an HIV-1E culture supernatant antigen, to elicit proliferative responses in HIV-seropositive and HIV-seronegative donors. Peripheral blood mononuclear cells from 12 HIV-seropositive donors (each with HIV-1 loads <4,000 copies/ml of plasma, >350 CD4 T lymphocytes/mm(3), and no antiretroviral therapy) and 15 HIV-seronegative donors were assessed with multiple concentrations of each stimulant by standard lymphocyte proliferation assays. Wide variations in response rates were found, with zero, three, five, and eight individuals demonstrating stimulation indices of >3 for the HIV culture antigen supernatant, gp120, p24, and inactivated whole-virus preparations, respectively. These results suggest that the use of the inactivated whole virus resulted in a more sensitive assay for detection of CD4 T-lymphocyte function in HIV-infected subjects.  相似文献   
52.
A male factor is implicated in more than 50% of couples treated with IVF. However, neither the routine testing of male fertility potential nor its treatment address the specific mechanisms by which spermatozoal factors may impact upon reproductive outcome. An important function of spermatozoa is to deliver the paternal genome to the oocyte. Recently, a number of acquired spermatozoal nuclear factors that may have implications on reproductive outcome have been described. These include non-specific DNA strand breaks, numerical abnormalities in spermatozoal chromosome content, Y chromosome microdeletions and alterations in the epigenetic regulation of paternal genome. The exact mechanisms by which these factors affect reproduction are unknown and their implications for assisted reproduction technology outcome need to be further investigated. These recent findings point to the need for novel and more personalized approaches to test and treat male factor infertility.  相似文献   
53.
This study tested cervical and oral human papillomavirus (HPV) infection in HIV-1 seropositive (HIV+) and seronegative (HIV-) women to determine any association between infections at both sites and the difference in prevalence of the HPV types infecting these women. Participants were 115 women referred to a colposcopy clinic after diagnosis of abnormal cervical cytology. The women showed low grade cervical intraepithelial neoplasia (CIN1) or high grade disease (CIN2/3) or no CIN based on colposcopy and histology. Typing of HPV in cervical and oral cells was by Roche linear array and included direct sequencing on selected oral samples. Cervical HPV prevalence was 86.5% and 97.1% in HIV- and HIV+ women respectively. With the exception of HPV-45, prominent in HIV+ women, the hierarchy of predominant types were similar in HIV- and HIV+ women. HPV-16 was most prevalent in both HIV+ (41.7%) and HIV- women (38.5%) with CIN2/3. Significantly more HIV+ women had multiple cervical (>1) infections than HIV- women (36.1% vs. 88.2%, P < 0.001) and more oral HPV infections (45.5% and 25% respectively; P = 0.04). The most prevalent oral HPV types were HPV-33, -11, and -72. The majority of women did not have concordant oral and cervical HPV types, reflecting possible independence of infection at the two sites. HIV immune suppression did not impact significantly on the predominant types of cervical HPV infection (except for HPV-45). HIV+ women had more multiple HPV infections and those with severe cervical disease a similar prevalence of HIV-16 but a lower HPV-18 prevalence than HIV- women.  相似文献   
54.

Background

While most young people who smoke want to quit, few access cessation support services. Mobile phone–based cessation programs are ideal for young people: mobile phones are the most common means of peer communication, and messages can be delivered in an anonymous manner, anywhere, anytime. Following the success of our text messaging smoking cessation program, we developed an innovative multimedia mobile phone smoking cessation intervention.

Objective

The aim of the study was to develop and pilot test a youth-oriented multimedia smoking cessation intervention delivered solely by mobile phone.

Methods

Development included creating content and building the technology platform. Content development was overseen by an expert group who advised on youth development principles, observational learning (from social cognitive theory), effective smoking cessation interventions, and social marketing. Young people participated in three content development phases (consultation via focus groups and an online survey, content pre-testing, and selection of role models). Video and text messages were then developed, incorporating the findings from this research. Information technology systems were established to support the delivery of the multimedia messages by mobile phone. A pilot study using an abbreviated 4-week program of video and text content tested the reliability of the systems and the acceptability of the intervention.

Results

Approximately 180 young people participated in the consultation phase. There was a high priority placed on music for relaxation (75%) and an interest in interacting with others in the program (40% would read messages, 36% would read a blog). Findings from the pre-testing phase (n = 41) included the importance of selecting “real” and “honest” role models with believable stories, and an interest in animations (37%). Of the 15 participants who took part in the pilot study, 13 (87%) were available for follow-up interviews at 4 weeks: 12 participants liked the program or liked it most of the time and found the role model to be believable; 7 liked the role model video messages (5 were unsure); 8 used the extra assistance for cravings; and 9 were happy with two messages per day. Nine participants (60%) stopped smoking during the program. Some technical challenges were encountered during the pilot study.

Conclusions

A multimedia mobile phone smoking cessation program is technically feasible, and the content developed is appropriate for this medium and is acceptable to our target population. These results have informed the design of a 6-month intervention currently being evaluated for its effectiveness in increasing smoking cessation rates in young people.  相似文献   
55.

Objective

to gain insight into the experiences and perspectives of pregnant women diagnosed antenatally with fetal lower urinary tract obstruction (LUTO) participating in an interventional fetal medicine randomised controlled trial (RCT).

Design

a qualitative study using semi-structured interviews. Interviews were analysed using Riessman's narrative analysis.

Setting

fetal medicine clinics within the United Kingdom National Health Service (NHS).

Participants

five pregnant women who were recruited as part of an RCT and two additional women who were recruited after the trial was terminated before completion.

Findings

three themes were identified and form the basis of this article: the use of technology in pregnancy, the loss of a normal pregnancy, and decision making in uncertainty.

Implications and conclusions

undertaking qualitative research within an RCT can illuminate the experience of the condition being studied. Women's experience of a pregnancy where LUTO was diagnosed in the fetus entailed an emotional journey following the visualisation of the abnormality through the use of routine ultrasound screening. Women tried to make sense of the diagnosis in order to make the best, albeit less than ideal, decisions for themselves, their baby, and their family. Midwives are in a good position to support women through the emotional distress of diagnosis and to help them negotiate the uncertain terrain in which they make decisions.  相似文献   
56.
Research questionDo multiple cryopreservation–warming cycles, coupled with blastocyst biopsy, negatively affect IVF outcomes?DesignPatients undergoing IVF with homologous single embryo transfer, and who underwent trophectoderm biopsy for preimplantation genetic testing for aneuploidy (PGT-A) between 2013 and 2017, were divided into three groups based on degree of embryonic micromanipulation: once-biopsied, once-cryopreserved (group BC, n = 2603), once-biopsied, twice-cryopreserved (group CBC, n = 95) and twice-biopsied, twice-cryopreserved (group BCBC, n = 15). The primary outcome was live birth; secondary outcomes included positive serum pregnancy test, clinical pregnancy and miscarriage.ResultsGroup CBC had a significantly lower chance of live birth (adjusted RR 0.57, 95% CI 0.41 to 0.79) and clinical pregnancy (adjusted RR 0.67, 95% CI 0.53 to 0.85) compared with group BC. Miscarriage rates were similar between groups BC and CBC (adjusted RR 1.3, 95% CI 0.64 to 2.7).ConclusionsMultiple cryopreservation–warming cycles, coupled with blastocyst biopsy, negatively affect IVF outcomes. Although PGT-A is thought to improve reproductive outcomes on a per transfer basis, caution must be exercised in counselling patients on the possibility of diminishing returns owing to further embryonic micromanipulation after an embryo has been cryopreserved.  相似文献   
57.
Despite research documenting the scope of disaster-related posttraumatic stress (PTS) in youth, less is known about how family processes immediately postdisaster might associate with child outcomes. The 2013 Boston Marathon bombing affords a unique opportunity to assess links between immediate family discussions about community trauma and child mental health outcomes. The present study examined associations between attack-related household discussions and child PTS among Boston-area youth ages 4 to 19 following the Marathon bombing (N = 460). Caregivers completed surveys 2 to 6 months postattack about immediate household discussions about the events, child exposure to potentially traumatic attack-related experiences, and child PTS. During the Marathon bombing and manhunt, there was considerable heterogeneity in household discussions across area families, and several discussion items were differentially predictive of variability in children’s PTS. Specifically, after controlling for children’s direct exposure to the potentially traumatic attack/manhunt events, children showed lower PTS when it was their caregivers who informed them about the attack and manhunt, and when their caregivers expressed confidence in their safety and discussed their own feelings about the manhunt with their child. Children showed higher PTS when their caregivers did not discuss the events in front of them, asked others to avoid discussing the events in front of them, and expressed concern at the time that their child might not be safe. Child age and traumatic attack/manhunt exposure moderated several links between household discussions and child PTS. Findings underscore the importance of family communication and caregiver modeling during times of community threat and uncertainty.  相似文献   
58.
Child and adolescent trauma exposure is prevalent, with trauma exposure-related symptoms, including posttraumatic stress, depressive, and anxiety symptoms often causing substantial impairment. This article updates the evidence base on psychosocial treatments for child and adolescent trauma exposure completed for this journal by Silverman et al. (2008). For this review, we focus on 37 studies conducted during the seven years since the last review. Treatments are grouped by overall treatment family (e.g., cognitive behavioral therapy), treatment modality (e.g., individual vs. group), and treatment participants (e.g., child only vs. child and parent). All studies were evaluated for methodological rigor according to Journal of Clinical Child & Adolescent Psychology evidence-based treatment evaluation criteria (Southam-Gerow & Prinstein, 2014), with cumulative designations for level of support for each treatment family. Individual CBT with parent involvement, individual CBT, and group CBT were deemed well-established; group CBT with parent involvement and eye movement desensitization and reprocessing (EMDR) were deemed probably efficacious; individual integrated therapy for complex trauma and group mind–body skills were deemed possibly efficacious; individual client-centered play therapy, individual mind–body skills, and individual psychoanalysis were deemed experimental; and group creative expressive + CBT was deemed questionable efficacy. Advances in the evidence base, with comparisons to the state of the science at the time of the Silverman et al. (2008) review, are discussed. Finally, we present dissemination and implementation challenges and areas for future research.  相似文献   
59.
60.
Oncogenic human papillomaviruses (HPVs) are obligate mucosal pathogens and typically cause localized infections. The mucosal surface of the genital tract also provides the first line of defense against genital HPV infection. Although local antibody production following HPV-infection has been demonstrated, their role in protection from cervical disease is unclear. This study evaluated oral and cervical HPV infection and the associated linkage between HPV-16 oral, cervical and serum antibody responses in 103 women with varying grades of cervical intraepithelial neoplasia (CIN). We found that HPV-16 was the most prevalent cervical HPV infection (30/103, 29.1%) but was only detected in 1.1% (1/91) of the oral samples. Both the frequency and magnitude of HPV-16-specific cervical IgA was significantly elevated in women with CIN 2/3 compared with women with CIN 1 (P = 0.0073 frequency; P = 0.0045 magnitude). Women with cervical HPV-16 infection had significantly higher magnitude and frequency of cervical HPV-16 IgA responses than women without cervical HPV-16 DNA (P = 0.0002 frequency; P = 0.0052 magnitude). Despite our contention that mucosal HPV-16 antibody responses within distinct mucosal compartments may be linked, the concordance analysis carried out within and between mucosal compartments and serum suggests that no such linkage exists and that these compartments may be functioning independently of one another. An HPV-16 specific antibody response in one mucosal compartment in women with CIN is therefore not predictive of a response at another.  相似文献   
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