Citations

Abstract Background: Given the high technical reproducibility and orders of magnitude greater resolution than microarrays, next-generation sequencing of mRNA (RNA-Seq) is quickly becoming the de facto standard for measuring levels of gene expression in biological experiments. Two important questions must be taken into consideration when designing a particular experiment, namely, 1) how deep does one need to sequence? and, 2) how many biological replicates are necessary to observe a significant change in expression? Results: Based on the gene expression distributions from 127 RNA-Seq experiments, we find evidence that 91% ± 4% of all annotated genes are sequenced at a frequency of 0.1 times per million bases mapped, regardless of sample source. Based on this observation, and combining this information with other parameters such as biological variation and technical variation that we empirically estimate from our large datasets, we developed a model to estimate the statistical power needed to identify differentially expressed genes from RNA-Seq experiments. Conclusions: Our results provide a needed reference for ensuring RNA-Seq gene expression studies are conducted with the optimally sample size, power, and sequencing depth. We also make available both R code and an Excel worksheet for investigators to calculate for their own experiments.

Abstract Background: The etiology and natural history of Parkinson’s disease (PD) are not well understood. Some non-motor symptoms such as hyposmia, rapid eye movement sleep behavior disorder, and constipation may develop during the prodromal stage of PD and precede PD diagnosis by years. Objectives: We examined the promise and pitfalls of research on premotor symptoms of PD and developed priorities and strategies to understand their clinical and etiological implications. Methods: This review was based on a workshop, Parkinson’s Disease Premotor Symptom Symposium, held 7–8 June 2012 at the National Institute of Environmental Health Sciences in Research Triangle Park, North Carolina. Discussion: Research on premotor symptoms of PD may offer an excellent opportunity to characterize high-risk populations and to better understand PD etiology. Such research may lead to evaluation of novel etiological hypotheses such as the possibility that environmental toxicants or viruses may initiate PD pathogenesis in the gastrointestinal tract or olfactory bulb. At present, our understanding of premotor symptoms of PD is in its infancy and faces many obstacles. These symptoms are often not specific to PD and have low positive predictive value for early PD diagnosis. Further, the pathological bases and biological mechanisms of these premotor symptoms and their relevance to PD pathogenesis are poorly understood. Conclusion: This is an emerging research area with important data gaps to be filled. Future research is needed to understand the prevalence of multiple premotor symptoms and their etiological relevance to PD. Animal experiments and mechanistic studies will further understanding of the biology of these premotor symptoms and test novel etiological hypothesis. Citation: Chen H, Burton EA, Ross GW, Huang X, Savica R, Abbott RD, Ascherio A, Caviness JN, Gao X, Gray KA, Hong JS, Kamel F, Jennings D, Kirshner A, Lawler C, Liu R, Miller GW, Nussbaum R, Peddada SD, Comstock Rick A, Ritz B, Siderowf AD, Tanner CM, Tröster AI, Zhang J. 2013. Research on the premotor symptoms of Parkinson’s Disease: clinical and etiological implications. Environ Health Perspect 121:1245–1252; http://dx.doi.org/10.1289/ehp.1306967

Objective To test a multidisciplinary approach to reduce heart failure (HF) readmissions that tailors the intensity of care transition intervention to the risk of the patient using a suite of electronic medical record (EMR)-enabled programmes. Methods A prospective controlled before and after study of adult inpatients admitted with HF and two concurrent control conditions (acute myocardial infarction (AMI) and pneumonia (PNA)) was performed between 1 December 2008 and 1 December 2010 at a large urban public teaching hospital. An EMR-based software platform stratified all patients admitted with HF on a daily basis by their 30-day readmission risk using a published electronic predictive model. Patients at highest risk received an intensive set of evidence-based interventions designed to reduce readmission using existing resources. The main outcome measure was readmission for any cause and to any hospital within 30 days of discharge. Results There were 834 HF admissions in the pre-intervention period and 913 in the post-intervention period. The unadjusted readmission rate declined from 26.2% in the pre-intervention period to 21.2% in the post-intervention period (p=0.01), a decline that persisted in adjusted analyses (adjusted OR (AOR)=0.73; 95% CI 0.58 to 0.93, p=0.01). In contrast, there was no significant change in the unadjusted and adjusted readmission rates for PNA and AMI over the same period. There were 45 fewer readmissions with 913 patients enrolled and 228 patients receiving intervention, resulting in a number needed to treat (NNT) ratio of 20. Conclusions An EMR-enabled strategy that targeted scarce care transition resources to high-risk HF patients significantly reduced the risk-adjusted odds of readmission.

This study was to evaluate the efficacy and safety of acupuncture for chronic functional constipation. Randomized controlled trials were searched in several databases. The primary outcome was a change in the number of weekly spontaneous bowel movements. The secondary outcomes included colonic transit activity, effective rate, Cleveland Clinic Score, and health-related quality of life score. Meta-analysis was done by using RevMan 5.1. After strict screening, 15 RCTs were included, containing 1256 participants. All of them were conducted in China and published in Chinese journals. Meta-analysis indicated that acupuncture for chronic functional constipation was probably as effective as conventional medical therapy in the change of bowel movements. For the colonic transit activity, acupuncture might be the same as conventional medical therapy and could be better than sham acupuncture. For the Cleveland Clinic Score, acupuncture was unlikely inferior to conventional medical therapy and the deep acupuncture was better than normal depth acupuncture in abdominal region. No obvious adverse event was associated with acupuncture for constipation. In conclusion, acupuncture for chronic functional constipation is safe and may improve weekly spontaneous bowel movements, quality of life, and relevant symptoms. However, the evidence was limited by the small sample size and the methodological quality.

Characterization of the viscoelastic mechanical properties of skin is important for improving accurate medical examination and diagnosis of disorders involving cutaneous and subcutaneous tissues; more thoroughly understanding skin biophysical and physiological properties; identifying normal and abnormal skin aging and disease processes; developing and applying improved pharmacologic and other therapeutic interventions; as well as cosmetic applications. Several noninvasive methods have been developed for measurement of mechanical properties of skin [1]. However, most methods measure a stiffness parameter but not the material properties of skin. For example, the suction method measures the displacement of skin in response to suction. The measurement is dependent on the aperture and fixation of probes and also difficult to interpret.

According to recent statistics from the American Heart Association, Heart Failure (HF) affects 5.7 million Americans [1]. HF is characterized by the global dilation of the heart, which leads to an increase in ventricular volume and a reduction in pumping efficiency. Several treatment strategies have been investigated to combat the adverse remodeling that leads to the progression of HF [2,3]. These therapies include reshaping the heart by means of surgical intervention and implantation of medical devices.

Background— Cardiac rehabilitation (CR) is recommended for all patients after coronary artery bypass surgery, yet little is known about the long-term mortality effects of CR in this population. Methods and Results— We performed a community-based analysis on residents of Olmsted County, Minnesota, who underwent coronary artery bypass surgery between 1996 and 2007. We assessed the association between subsequent outpatient CR attendance and long-term survival. Propensity analysis was performed. Cox proportional hazards regression was then used to assess the association between CR attendance and all-cause mortality adjusted for the propensity to attend CR. We identified 846 eligible patients (age 66±11 years, 76% men, and 96% non-Hispanic whites) who survived at least 6 months after surgery, of whom 582 (69%) attended CR. During a mean (±SD) follow-up of 9.0±3.7 years, the 10-year all-cause Kaplan-Meier mortality rate was 28% (193 deaths). Adjusted for the propensity to attend CR, participation in CR was associated with a 10-year relative risk reduction in all-cause mortality of 46% (hazard ratio, 0.54; 95% confidence interval, 0.40–0.74; P <0.001) and a 10-year absolute risk reduction of 12.7% (number needed to treat=8). There was no evidence of a differential effect of CR on mortality with respect to age (≥65 versus <65 years), sex, diabetes, or prior myocardial infarction. Conclusions— CR attendance is associated with a significant reduction in 10-year all-cause mortality after coronary artery bypass surgery. Our results strongly support national standards that recommend CR for this patient group.

SummaryPre‐existing central nervous system (CNS) involvement may influence referral for autologous haematopoietic cell transplantation (AHCT) for patients with non‐Hodgkin lymphoma (NHL). The outcomes of 151 adult patients with NHL with prior secondary CNS involvement (CNS+) receiving an AHCT were compared to 4688 patients without prior CNS lymphoma (CNS−). There were significant baseline differences between the cohorts. CNS+ patients were more likely to be younger, have lower performance scores, higher age‐adjusted international prognostic index scores, more advanced disease stage at diagnosis, more aggressive histology, more sites of extranodal disease, and a shorter interval between diagnosis and AHCT. However, no statistically significant differences were identified between the two groups by analysis of progression‐free survival (PFS) and overall survival (OS) at 5 years. A matched pair comparison of the CNS+ group with a subset of CNS− patients matched on propensity score also showed no differences in outcomes. Patients with active CNS lymphoma at the time of AHCT (n = 55) had a higher relapse rate and diminished PFS and OS compared with patients whose CNS lymphoma was in remission (n = 96) at the time of AHCT. CNS+ patients can achieve excellent long‐term outcomes with AHCT. Active CNS lymphoma at transplant confers a worse prognosis.

Cardiac metastasis in renal cell carcinoma is a very rare entity, with only a few previously reported cases. In this series, we report two cases of ventricular metastases from renal cell carcinoma without vena cava or right atrial involvement. The first case involves an initially isolated inoperable metastasis to the left ventricle, which was treated with systemic targeted therapy with favorable local response. Our second case illustrates a patient with an isolated cardiac metastasis in the interventricular septum with extension into the right ventricle, which has also remained stable in size on systemic targeted therapy. Although anti-angiogenic agents such as tyrosine kinase inhibitors have transformed the treatment of metastatic renal cell carcinoma in recent years, their efficacy and safety in treating patients with metastatic disease in highly vascular organs such as the heart are currently unknown, with no prior reports on this topic. We describe our novel management of these unique cases and discuss the current medical and surgical approaches to treating cardiac metastases from renal cell carcinoma.