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81.

Purpose

Evidence suggests that young adults experiencing homelessness (YEH) are at elevated risk of HIV compared to housed youth. Given the limited research on pre-exposure prophylaxis (PrEP) awareness among YEH, this study examined their PrEP knowledge and attitudes.

Methods

Data from a cross-sectional survey among YEH (ages 18–26) (n?=?1,427) in seven U.S. cities were used to assess their knowledge and attitudes regarding PrEP to inform HIV prevention efforts.

Results

Participants were primarily male youth of color. The mean age was 20.9years. While 66% felt at risk for HIV, only 14% strongly agreed that they try to protect themselves from getting infected with HIV. Most (84%) were eligible for PrEP based on risk, yet only 29% had knowledge of PrEP. Despite this, 59% reported they were likely/extremely likely to take PrEP. Access to free PrEP (55%), HIV testing (72%), healthcare (68%), and one-on-one (62%), and text messaging support (57%) were rated as very/extremely important for PrEP uptake and adherence.

Conclusions

The results of this study suggest missed opportunities to prevent new HIV infections among YEH. Efforts to increase PrEP uptake among this population should consider provider- and system-level interventions to increase PrEP awareness, decrease PrEP-associated healthcare costs, improve access to PrEP providers, and provide in-person and text messaging support.  相似文献   
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Background

MCPH1 is a proximal regulator of DNA damage response pathway that is involved in recruitment of phosphorylated ATM to double-stranded DNA breaks.

Methods

To understand the importance of MCPH1 and ATM in deregulation of DNA damage response pathway in breast carcinoma, we studied m-RNA expression and genetic/epigenetic alterations of these genes in primary breast carcinoma samples.

Results

Our study revealed reduced expression (mRNA/protein) and high alterations (deletion/methylation) (96 %, 121 of 126) of MCPH1 and ATM. Mutation was, however, rare in inactivation of MCPH1. In immunohistochemical analysis, reduced protein expression of MCPH1, ATM and p-ATM were concordant with their molecular alterations (P = 0.03–0.01). Alterations of MCPH1 and deletion of ATM were significantly high in estrogen/progesterone receptor–negative than estrogen/progesterone receptor–positive breast carcinoma samples compared to early or late age of onset tumors, indicating differences in pathogenesis of the molecular subtypes (P = 0.004–0.01). These genes also showed differential association with tumor stage, grade and lymph node status in different subtypes of breast carcinoma (P = 0.00001–0.01). Their coalterations showed significant association with tumor progression and prognosis (P = 0.003–0.05). Interestingly, patients with alterations of these genes or MCPH1 alone had poor outcome after treatment with DNA-interacting drugs and/or radiation (P = 0.01–0.05).

Conclusions

Inactivation of MCPH1-ATM-associated DNA damage response pathway might have an important role in the development of breast carcinoma with diagnostic, prognostic and therapeutic implications.

  相似文献   
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Background We investigated whether associations between prevalent diabetes and cancer risk are pertinent to older adults and whether associations differ across subgroups of age, body weight status or levels of physical activity.Methods We harmonised data from seven prospective cohort studies of older individuals in Europe and the United States participating in the CHANCES consortium. Cox proportional hazard regression was used to estimate the associations of prevalent diabetes with cancer risk (all cancers combined, and for colorectum, prostate and breast). We calculated summary risk estimates across cohorts using pooled analysis and random-effects meta-analysis.Results A total of 667,916 individuals were included with an overall median (P25–P75) age at recruitment of 62.3 (57–67) years. During a median follow-up time of 10.5 years, 114,404 total cancer cases were ascertained. Diabetes was not associated with the risk of all cancers combined (hazard ratio (HR) = 0.94; 95% confidence interval (CI): 0.86–1.04; I2 = 63.3%). Diabetes was positively associated with colorectal cancer risk in men (HR = 1.17; 95% CI: 1.08–1.26; I2 = 0%) and a similar HR in women (1.13; 95% CI: 0.82–1.56; I2 = 46%), but with a confidence interval including the null. Diabetes was inversely associated with prostate cancer risk (HR = 0.81; 95% CI: 0.77–0.85; I2 = 0%), but not with postmenopausal breast cancer (HR = 0.96; 95% CI: 0.89–1.03; I2 = 0%). In exploratory subgroup analyses, diabetes was inversely associated with prostate cancer risk only in men with overweight or obesity.Conclusions Prevalent diabetes was positively associated with colorectal cancer risk and inversely associated with prostate cancer risk in older Europeans and Americans.Subject terms: Risk factors, Cancer epidemiology  相似文献   
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