In group sequential clinical trials, sample size reestimation can be a complicated issue when it allows for change of sample size to be influenced by an observed sample path. Our simulation studies show that increasing sample size based on an interim estimate of the treatment difference can substantially inflate the probability of type I error in most practical situations. A new group sequential test procedure is developed by modifying the weights used in the traditional repeated significance two-sample mean test. The new test has the type I error probability preserved at the target level and can provide a substantial gain in power with the increase of sample size. Generalization of the new procedure is discussed.

While many diseases of aging have been linked to the immunological system, immune metrics with which to identify the most at-risk individuals are lacking. We studied the blood immunome of 1001 individuals aged 8-96 and developed a deep learning method based on patterns of systemic age-related inflammation. The resulting inflammatory clock of aging (iAge) tracked with multiple morbidities, immunosenescence, frailty and cardiovascular aging. We demonstrate that iAge is associated with exceptional longevity in a separate cohort of centenarians. The strongest contributor to this metric was the chemokine CXCL9, which was involved in cardiac aging, adverse cardiac remodeling, and decreased vascular function.Furthermore, aging endothelial cells in human and mice show loss of function, indicators of early cellular senescence and hallmark phenotypes of arterial stiffness, all of which are reversed by silencing CXCL9. In conclusion, we identify a key role of CXCL9 in age-related systemic chronic inflammation and derive a novel metric for age-related multimorbidity that can also be used for early detection of age-related clinical phenotypes.

Fibrotic diseases are not well-understood. They represent a number of different diseases that are characterized by the development of severe organ fibrosis without any obvious cause, such as the devastating diseases idiopathic pulmonary fibrosis (IPF) and scleroderma. These diseases have a poor prognosis comparable with endstage cancer and are uncurable. Given the phenotypic differences, it was assumed that the different fibrotic diseases also have different pathomechanisms. Here, we demonstrate that many endstage fibrotic diseases, including IPF; scleroderma; myelofibrosis; kidney-, pancreas-, and heart-fibrosis; and nonalcoholic steatohepatosis converge in the activation of the AP1 transcription factor c-JUN in the pathologic fibroblasts. Expression of the related AP1 transcription factor FRA2 was restricted to pulmonary artery hypertension. Induction of c-Jun in mice was sufficient to induce severe fibrosis in multiple organs and steatohepatosis, which was dependent on sustained c-Jun expression. Single cell mass cytometry revealed that c-Jun activates multiple signaling pathways in mice, including pAkt and CD47, which were also induced in human disease. αCD47 antibody treatment and VEGF or PI3K inhibition reversed various organ c-Jun–mediated fibroses in vivo. These data suggest that c-JUN is a central molecular mediator of most fibrotic conditions.

IMPORTANCE The aging of the population is associated with an increasing burden of fractures worldwide. However, the epidemiological features of fractures in mainland China are not well known. OBJECTIVE To assess the prevalence of and factors associated with osteoporosis, clinical fractures, and vertebral fractures in an adult population 40 years or older in mainland China. DESIGN, SETTING. AND PARTICIPANTS This cross-sectional study, the China Osteoporosis Prevalence Study, was conducted from December 2017 to August 2018. A random sample of individuals aged 20 years or older who represented urban and rural areas of China were enrolled, with a 99% participation rate. MAIN OUTCOMES AND MEASURES Weighted prevalence of osteoporosis, clinical fracture, and vertebral fracture by age, sex, and urban vs rural residence as determined by x-ray absorptiometry, questionnaire, and radiography. RESULTS A total of 20 416 participants were included in this study; 20 164 (98.8%; 11 443 women [56.7%]; mean [SD] age, 53 [13] years) had a qualified x-ray absorptiometry image and completed the questionnaire, and 8423 of 8800 (95.7%) had a qualified spine radiograph. The prevalence of osteoporosis among those aged 40 years or older was 5.0% (95% CI, 4.2%-5.8%) among men and 20.6% (95% CI, 19.3%-22.0%) among women. The prevalence of vertebral fracture was 10.5% (95% CI, 9.0%-12.0%) among men and 9.7% (95% CI, 8.2%-11.1%) among women. The prevalence of clinical fracture in the past 5 years was 4.1% (95% CI, 3.3%-4.9%) among men and 4.2% (95% CI, 3.6%-4.7%) among women. Among men and women, 0.3% (95% CI, 0.0%-0.7%) and 1.4% (95% CI, 0.8%-2.0%), respectively, with osteoporosis diagnosed on the basis of bone mineral density or with fracture were receiving antiosteoporosis treatment to prevent fracture. CONCLUSIONS AND RELEVANCEIn this cross-sectional study of an adult population in mainland China, the prevalence of osteoporosis and vertebral fracture were high and the prevalence of vertebral fracture and clinical fracture was similarly high in men and women. These findings suggest that current guidelines for screening and treatment of fractures among patients in China should focus equally on men and women and should emphasize the prevention of vertebral fractures.

The transcription factor JUN is highly expressed in pulmonary fibrosis. Its induction in mice drives lung fibrosis, which is abrogated by administration of anti-CD47. Here, we use high-dimensional mass cytometry to profile protein expression and secretome of cells from patients with pulmonary fibrosis. We show that JUN is activated in fibrotic fibroblasts that expressed increased CD47 and PD-L1. Using ATAC-seq and ChIP-seq, we found that activation of JUN rendered promoters and enhancers of CD47 and PD-L1 accessible. We further detect increased IL-6 that amplified JUN-mediated CD47 enhancer activity and protein expression. Using an in vivo mouse model of fibrosis, we found two distinct mechanisms by which blocking IL-6, CD47 and PD-L1 reversed fibrosis, by increasing phagocytosis of profibrotic fibroblasts and by eliminating suppressive effects on adaptive immunity. Our results identify specific immune mechanisms that promote fibrosis and suggest a therapeutic approach that could be used alongside conventional anti-fibrotics for pulmonary fibrosis.