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1.
Evidence suggests that aspirin use reduces the occurrence of colorectal neoplasia. Few studies have investigated the association among Black Americans, who are disproportionately burdened by the disease. We assessed aspirin use in relation to colorectal adenoma among Black women. The Black Women's Health Study is a prospective cohort of self-identified Black American women established in 1995. Participants reported regular aspirin use on baseline and follow-up questionnaires. Beginning in 1999, participants reported undergoing a colonoscopy or sigmoidoscopy, the only procedures through which colorectal adenomas can be diagnosed. Multivariable logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI) for associations between aspirin use and colorectal adenoma among 34 397 women who reported at least 1 colonoscopy or sigmoidoscopy. From 1997 through 2018, 1913 women were diagnosed with an adenoma. Compared to nonaspirin users, regular users had 14% (OR = 0.86, 95% CI: 0.78-0.95) lower odds of adenoma. The odds of adenoma decreased with increasing duration of aspirin use (≥10 years: OR = 0.80, 95% CI: 0.66-0.96). Initiating aspirin at a younger age was associated with a reduced adenoma occurrence (age < 40 years at initiation: OR = 0.69, 95% CI: 0.55-0.86). Regular aspirin use was associated with a decreased odds of colorectal adenoma in our study of Black women. These findings support evidence demonstrating a chemopreventive impact of aspirin on colorectal neoplasia and suggest that aspirin may be a useful prevention strategy among US Black women.  相似文献   
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Kidney transplant recipients who develop coronavirus disease 2019 (COVID-19) are at increased risk of life-threatening illness, which often requires reducing immunosuppression despite the potential risk of causing an allograft rejection. Herein, we describe the clinical presentation and course of a kidney transplant recipient who acquired COVID-19 and was hospitalized with severe symptoms and hypoxemia. Upon admission, the patient was found to have elevated de novo donor-specific antibodies (DSA) yielding a positive cytotoxicity crossmatch and concurrent elevated plasma donor-derived cell-free DNA (dd-cfDNA) level, indicating a possible ongoing rejection despite improvement in his serum creatinine. Because of persistent positive COVID-19 tests and stable serum creatinine, a kidney allograft biopsy was initially deferred and his dd-cfDNA and DSA were monitored closely postdischarge. Three months later, because of persistent elevated dd-cfDNA and positive DSA, a kidney allograft biopsy was performed, which showed chronic active antibody-mediated rejection. Accordingly, the patient was treated with intravenous immunoglobulin and his maintenance immunosuppressive regimen was increased.  相似文献   
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Background

Parents’ attitudes and beliefs in vaccination are important to understand for shaping vaccine acceptance and demand interventions. Little research has focused on developing a validated scale to measure parents’ attitudes towards vaccinations in low and middle-income countries; Ghana provided an opportunity develop a caregiver vaccination attitudes scale (CVAS) validated against childhood vaccine compliance.

Methods

We conducted a cluster survey of 373 households with children aged 12–35?months of age from Northern Region, Ghana. Caregivers responded to 22 vaccination behavior and belief survey items and provided the child’s vaccination status. In exploratory factor analysis (EFA) to assess CVAS content validity, we used parallel analysis to guide the number of factors to extract and principal axis factor analysis for factor extraction. Reliability of the scale was assessed using McDonald’s Omega coefficient. Criterion validity of scale and subscales was assessed against receipt of vaccinations by 12?months of age and vaccination delay, using number of days undervaccinated.

Results

EFA of CVAS responses resulted in removing 11 of 22 survey items due to loadings <0.30 and development of a 5-factor structure with subscales for Vaccine-Preventable Disease (VPD) Awareness, Vaccine Benefits, Past Behavior, Vaccine Efficacy and Safety, and Trust. The 5 factors accounted for 69% of the common variance and omega coefficients were >0.73 for all subscales. Validity analysis indicated that for every unit increase in the parent’s scale score, the odds of the child being vaccinated decreased by 0.58 (95% confidence interval [CI]: 0.37, 0.68) and the number of days under-vaccinated increased by 86 (95%CI: 28, 143). The final 3-factor scale included Vaccine Benefits, Past Behavior, and Vaccine Efficacy and Safety.

Discussion

The final CVAS included three factors associated with vaccine compliance in Ghana, although several survey items suggested for use in vaccine acceptance scales were dropped. Replicating this study in several country settings will provide additional evidence to assist in refining a tool for use in routine vaccine acceptance and demand surveillance efforts.  相似文献   
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