Evaluating the Relationship between Spermatogenic Silencing of the X Chromosome and Evolution of the Y Chromosome in Chimpanzee and Human

Chimpanzees and humans are genetically very similar, with the striking exception of their Y chromosomes, which have diverged tremendously. The male-specific region (MSY), representing the greater part of the Y chromosome, is inherited from father to son in a clonal fashion, with natural selection acting on the MSY as a unit. Positive selection might involve the performance of the MSY in spermatogenesis. Chimpanzees have a highly polygamous mating behavior, so that sperm competition is thought to provide a strong selective force acting on the Y chromosome in the chimpanzee lineage. In consequence of evolution of the heterologous sex chromosomes in mammals, meiotic sex chromosome inactivation (MSCI) results in a transcriptionally silenced XY body in male meiotic prophase, and subsequently also in postmeiotic repression of the sex chromosomes in haploid spermatids. This has evolved to a situation where MSCI has become a prerequisite for spermatogenesis. Here, by analysis of microarray testicular expression data representing a small number of male chimpanzees and men, we obtained information indicating that meiotic and postmeiotic X chromosome silencing might be more effective in chimpanzee than in human spermatogenesis. From this, we suggest that the remarkable reorganization of the chimpanzee Y chromosome, compared to the human Y chromosome, might have an impact on its meiotic interactions with the X chromosome and thereby on X chromosome silencing in spermatogenesis. Further studies will be required to address comparative functional aspects of MSCI in chimpanzee, human, and other placental mammals

Once-Weekly Single-Set Resistance Training Improves Perceived Physical Function and Energy/Fatigue in Older Adults

Lack of energy, fear of discomfort/pain, time, motivation, and psychological considerations are among the barriers that inhibit the participation of older individuals in regular physical activity. Participation in physical activity has been demonstrated to help with the maintenance of physical, cognitive, and emotional health. The Exercise is Medicine Initiative is managed by the American College of Sports Medicine the purpose of which is to make physical activity assessment and promotion a standard in clinical care. This initiative encourages physicians and other health care providers to include physical activity when designing treatment plans. PURPOSE: The purpose of the project was to determine whether six weeks of a once-weekly single-set strength training program would elicit changes in perceived function, health, and quality of life. METHODS: Fifteen individuals (5 males and 10 females) aged 65 ± 6.84 years, height 66.07 ± 4.06 inches weight 168.8 ± 48.07lbs body fat 39.78 ± 8.60%, participated in a Pre/Post within subjects testing research design. Prior to training each participant had their body composition measured with a DEXA and completed the Short Form 36 which is self-reported measure of perceived function, health, and quality of life. The Short Form 36 includes items that assess perceived physical function, role limitations due to physical health, emotion problems, energy/fatigue, emotional well-being, social functioning, pain, and general health. Following the initial testing participants engaged once per week strength training sessions to failure for six weeks. After the six-week training period participants underwent the same testing protocol. A Wilcoxon Signed Rank Test was used for statistical comparisons with p £ 0.05 used for significance. RESULTS: Perceived physical functioning (pre 87.00 ± 7.51, post 91.33 ± 9.72, p = 0.039) and energy/fatigue (pre 64.33 ± 14.74, post 74.33 ± 11.48, p = 0.011) both improved following the training. Significant differences were not observed for any of the other areas assessed by the Short Form 36. CONCLUSION: Based on the data from this investigation engaging in a single strength training session to failure per week results in improvement in perceived physical function and energy/fatigue in a cohort of older individuals. The findings of this investigation also provides support to the Exercise is Medicine initiative of the American College of Sports Medicine by demonstrating improvement in psychological considerations associated with barriers to physical activity. Moreover, these results demonstrate that a minimal dose of exercise per week elicits positive attributes that can fuel affirmative lifestyle changes that can enhance quality of life in older individuals

Survival outcomes in node-positive non-metastatic bladder cancer: An analysis of the national cancer database

Introduction: Clinically node-positive non-metastatic bladder cancer (cN+) has been the target of several studies aiming to establish a standard of care for this population. Limited studies have shown a survival benefit for various multimodal therapy approaches. The role of radiation therapy has not been well established. Our study aims to study the trends of the reported treatment options offered to patients with cN+ bladder cancer in a national database and to evaluate the effect of various treatments, including radiation, on survival. Methods: The National Cancer Database (NCDB) was used to identify cN+ bladder cancer patients who received chemotherapy alone or in combination with radical cystectomy (RC) or radiotherapy. 3,481 patients were included and divided into 4 groups: chemotherapy only, chemotherapy and RC, chemotherapy and radiation therapy, and chemotherapy, RC, and radiation therapy. Demographic data was compared using ANOVA for continuous variables, and Chi-square for categorical variables. Multivariable analysis was done to compare groups using a multinomial logistic regression model. Kaplan-Meier test was used for survival analysis and Cox-Regression was used for multivariable survival analysis. Results: Patients undergoing RC were significantly younger (P <0.001). There was a significant difference between the groups regarding racial distribution, facility-type and insurance status. There was no difference in gender, Charlson\Deyo score, financial or educational status. Patients who underwent combination therapy with chemotherapy and RC were found to have the longest median survival time at 27 months. Multivariable analysis showed that final treatment, age, sex, Charlson\Deyo comorbidity score, TNM edition and facility-type were significant survival predictors. Race, insurance and financial status failed to maintain significance. There was no survival difference between the chemotherapy group and chemo-radiotherapy group. Conclusions: The combination of surgery and chemotherapy achieves statistically significant superior survival in cN+ bladder cancer. Adding radiotherapy to chemotherapy did not improve survival in this group of patients

A Rapid Single-Cell Antimicrobial Susceptibility Testing Workflow for Bloodstream Infections

Bloodstream infections are a significant cause of morbidity and mortality worldwide. The rapid initiation of effective antibiotic treatment is critical for patients with bloodstream infections. However, the diagnosis of bloodborne pathogens is largely complicated by the matrix effect of blood and the lengthy blood tube culture procedure. Here we report a culture-free workflow for the rapid isolation and enrichment of bacterial pathogens from whole blood for single-cell antimicrobial susceptibility testing (AST). A dextran sedimentation step reduces the concentration of blood cells by 4 orders of magnitude in 20–30 min while maintaining the effective concentration of bacteria in the sample. Red blood cell depletion facilitates the downstream centrifugation-based enrichment step at a sepsis-relevant bacteria concentration. The workflow is compatible with common antibiotic-resistant bacteria and does not influence the minimum inhibitory concentrations. By applying a microfluidic single-cell trapping device, we demonstrate the workflow for the rapid determination of bacterial infection and antimicrobial susceptibility testing at the single-cell level. The entire workflow from blood to categorical AST result can be completed in less than two hours

A Method for Describing Preschoolers' Activity Preferences

We designed a series of analyses to develop a measurement system capable of simultaneously recording the free-play patterns of 20 children in a preschool classroom. Study 1 determined the intermittency with which the location and engagement of each child could be momentarily observed before the accuracy of the measurement was compromised. Results showed that intervals up to 120 s introduced less than 10% measurement error. Study 2 determined the extent of agreement between two observers who simultaneously collected data for 20 children using 30-, 60-, 90-, and 120-s momentary time sampling (MTS) intervals. The three larger intervals resulted in high levels of interobserver agreement (above 90%), whereas the 30-s interval resulted in unacceptably low levels of agreement (less than 80%). By allowing observers to select from among the different MTS intervals via a datasheet array and then collect data with the chosen system, Study 3 determined observers' preferences for the remaining MTS intervals. Both data collectors preferred the 90-s MTS procedure. The sensitivity of the 90-s MTS procedure, which was shown to be accurate, reliable, and preferred, was then demonstrated by its use to describe activity preferences of a classroom of children in Study 4. This system identified high- and low-preference activities for individual children and revealed interesting patterns of response allocation by the group