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Chronic granulomatous disease (CGD) is an inherited immunodeficiency due to defective leukocyte NADPH responsible for recurrent infections and aberrant inflammation. Mutations in the CYBB gene are responsible for the X-linked CGD and account for approximately 70% of the cases. CGD is diagnosed during childhood in males. Female carriers may have biased X-inactivation and may present with clinical manifestations depending on the level of residual NADPH oxidase activity. We report the case of a previously asymptomatic female carrier who was diagnosed at age 67 with a skin infection with the rare fungus Paecilomyces lilacinus as the first manifestation of CGD. Dihydrorhodamine 123 (DHR) activity was below 10%. Next-generation sequencing (NGS) revealed mutations in DNMT3A, ASXL1, and STAG2 suggesting that clonal hematopoiesis could be responsible for a progressive loss of NADPH oxidase activity and the late onset of X-linked CGD in this patient. Long-term follow-up of asymptomatic carrier women seems to be essential after 50 years old.

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Objectives

To examine the potential added value of a simple 5-item questionnaire for sarcopenia screening (SARC-F) to the Fracture Risk Assessment Tool (FRAX) for hip fracture risk prediction, in order to identify at-risk older adults for screening with dual-energy x-ray absorptiometry (DXA).

Design

A prospective cohort study.

Setting and participants

Two thousand Chinese men and 2000 Chinese women aged 65 years or older were recruited from local communities and were prospectively followed up for about 10 years.

Measures

Areal bone mineral density (BMD) of hip and lumbar spine were measured by DXA at baseline. Ten-year FRAX probability of hip fracture was calculated using the baseline risk factors. Information from the baseline questionnaire was extracted to calculate a modified SARC-F score. The independent predictive values of SARC-F and FRAX questionnaire were evaluated using multivariate survival analysis. The added predictive values of SARC-F to FRAX for pre-DXA screening were examined.

Results

During the follow-up, 63 (3.2%) men and 69 (3.5%) women had at least 1 incident hip fracture. SARC-F had an independent value of FRAX for hip fracture risk prediction, with an adjusted hazard ratio [95% confidence interval (CI)] of 1.24 (1.02, 1.52) and 1.15 (0.99, 1.13) in men and women, respectively. Compared with using FRAX, using SARC-F in conjunction with FRAX made the sensitivity for prediction rise from 58.7% to 76.2% in men and from 69.6% to 78.3% in women, with a nondecreased area under receiver operating characteristic curve of 0.67. Prescreening using FRAX in conjunction with SARC-F could save more than half of the DXA assessment than with no prescreening.

Conclusions/Implications

SARC-F is associated with a modest increase in hip fracture risk, especially in men. Conjoint evaluation for sarcopenia in addition to FRAX screening may help identify older adults at higher risk of hip fracture for more intensive screening and/or preventive interventions.  相似文献   
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The “delayed infection hypothesis” states that a paucity of infections in early childhood may lead to higher risks of childhood leukemia (CL), especially acute lymphoblastic leukemia (ALL). Using prospectively collected data from six population-based birth cohorts we studied the association between birth order (a proxy for pathogen exposure) and CL. We explored whether other birth or parental characteristics modify this association. With 2.2 × 106 person-years of follow-up, 185 CL and 136 ALL cases were ascertained. In Cox proportional hazards models, increasing birth order (continuous) was inversely associated with CL and ALL; hazard ratios (HR) = 0.88, 95% confidence interval (CI): (0.77–0.99) and 0.85: (0.73–0.99), respectively. Being later-born was associated with similarly reduced hazards of CL and ALL compared to being first-born; HRs = 0.78: 95% CI: 0.58–1.05 and 0.73: 0.52–1.03, respectively. Successive birth orders were associated with decreased CL and ALL risks (P for trend 0.047 and 0.055, respectively). Multivariable adjustment somewhat attenuated the associations. We found statistically significant and borderline interactions between birth weight (p = 0.024) and paternal age (p = 0.067), respectively, in associations between being later-born and CL, with the lowest risk observed for children born at <3 kg with fathers aged 35+ (HR = 0.18, 95% CI: 0.06–0.50). Our study strengthens the theory that increasing birth order confers protection against CL and ALL risks, but suggests that this association may be modified among subsets of children with different characteristics, notably advanced paternal age and lower birth weight. It is unclear whether these findings can be explained solely by infectious exposures.  相似文献   
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Vismodegib treatment of multiple basal cell carcinomas (BCCs) is limited by adverse effects and high relapse rates: intermittent regimens are therefore preferred for long‐term administration. The objective of this study was to investigate clinical and dermoscopic changes in BCCs during long‐term intermittent treatment and to identify those most indicative of tumor persistence/clearing. Clinical and dermoscopic images (n = 380 each) of 38 BCCs were acquired at 10 observation times (t0–t9). Biopsies were performed at baseline (t0) and after 72 weeks of treatment (t9). All images were evaluated retrospectively by experts who assessed the presence/absence of 12 clinical and 14 dermoscopic features: clinical scores (CScs) and dermoscopic scores (DScs) were then calculated.  相似文献   
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