The effect of hydroxypropyl-[beta]-cyclodextrin and egg yolk concentration on cryopreservation and post-thaw parameters of jack and stallion semen

Pregnancy rates following artificial insemination with frozen-thawed jack spermatozoa have been relatively low compared to those attained in other species. Cholesterol is known to interfere with post-thaw fertility of jack and stallion semen. Altering the amount of cholesterol in the freezing extender may improve the fertility of frozen-thawed jack semen. Here we report clinical work completed with semen collected from a single jack; extended in EZ Mixin RTM OF and slowly cooled to 5°C. Extended semen samples were then centrifuged at 400G for 10 minutes and the supernatant removed. The spermatozoa were frozen in liquid nitrogen vapor after resuspension in the appropriate freezing medium to a final concentration of 400 x 106 cells/mL. Freezing extender treatments were: (1) 20% Egg yolk (EY); (2) 5% EY; and (3) 20% EY + 60mM hydroxypropyl-beta-cyclodextrin (beta-CD). A total of 28 mares 2 to 18 years in age were utilized over 5 breeding seasons (82 total cycles). Mares were administered human chorionic gonadotropin (hCG) to induce ovulation when the dominant follicle was ≥35 mm as assessed by ultrasonography and were inseminated within 6 hours pre-ovulation and again within 6 hours post-ovulation. Pregnancy rates for each treatment were as follows: (1) 6.25% (1 pregnancy, 15 matings), (2) 46.5% (20 pregnancies, 43 matings), (3) 58.5% (14 pregnancies, 24 matings). These data support the theory of cholesterol interfering with post-thaw fertility of jack semen. We have established that mule pregnancies can be achieved at acceptable rates with frozen-thawed jack semen cryopreserved in 5%EY and 20% EY + 60 mM beta-cyclodextrin transferred directly post-thaw.;Cyclodextrins are reported to improve post-thaw viability and motility in boar semen. Cyclodextrin mediates cholesterol efflux and subsequent acrosome reaction and capacitation in the sperm cells of several species in vitro. The second objective of this study was to evaluate whether or not addition of hydroxypropyl-beta-cyclodextrin to freezing extenders containing low or high concentrations of egg yolk (cholesterol source) would improve laboratory indicators of fertility for jack and stallion semen and to evaluate post-thaw effects of cyclodextrin on acrosome reaction. Post-thaw motility was improved (p\u3c.05) for jack semen cryopreserved in freezing extender containing 20% egg yolk and 60 mM beta-cyclodextrin compared to 5% egg yolk freezing extender, with all other treatments for jack and stallions being similar. Post-thaw viability was not different for species or freeze treatments. Post-thaw addition of cyclodextrin to jack and stallion sperm for 90 minutes induced the acrosome reaction 93.5+/-5.94% and 22.5 +/- 4.66% of viable cells, respectively, as measured by a triple stain procedure and subsequent analysis via flow cytometry. Here we have demonstrated that hydroxy-propyl-beta-cylcodextrin can be utilized as a powerful agent of induction of acrosome reaction for the jack and stallion semen

From the adiabatic piston to macroscopic motion induced by fluctuations

The controversial problem of an isolated system with an internal adiabatic wall is investigated with the use of a simple microscopic model and the Boltzmann equation. In the case of two infinite volume one-dimensional ideal fluids separated by a piston whose mass is equal to the mass of the fluid particles we obtain a rigorous explicit stationary non-equilibrium solution of the Boltzmann equation. It is shown that at equal pressures on both sides of the piston, the temperature difference induces a non-zero average velocity, oriented toward the region of higher temperature. It thus turns out that despite the absence of macroscopic forces the asymmetry of fluctuations results in a systematic macroscopic motion. This remarkable effect is analogous to the dynamics of stochastic ratchets, where fluctuations conspire with spatial anisotropy to generate direct motion. However, a different mechanism is involved here. The relevance of the discovered motion to the adiabatic piston problem is discussed.Comment: 14 pages,1 figur

Predicting in-role and extra-role performance by gender

Men and women are said to perceive justice differently, with women proposed to be more concerned with relational issues and men focused more on material issues. In this study, the potential for differential effects of justice on performance by gender was analyzed across the four contemporary types of justice. Respondents were 265 male and 113 female occupationally diverse employees in a single organization. The results show significant differences in how men and women respond to the four justice types with only one - informational justice - acting similarly by gender. Women were more interested in maintaining social harmony than men. The results appear to strongly support the use of the justice judgment model over the group-value model as a means of explaining the gender differences. Implications for management include the importance of informational justice both generally and within the performance appraisal process<br /

Extracellular vesicles produced in B cells deliver tumor suppressor miR-335 to breast cancer cells disrupting oncogenic programming in vitro and in vivo.

The successful implementation of miRNA (miR) therapies in humans will ultimately rely on the use of vehicles with improved cellular delivery capability. Here we tested a new system that leverages extracellular vesicles (EVs) laden with a tumor suppressor miRNA (miR-335) produced in B cells by plasmid DNA induction (iEVs). We demonstrate that iEVs-335 efficiently and durably restored the endogenous miR-335 pool in human triple negative breast cancer cells, downregulated the expression of the miR-335 target gene SOX4 transcription factor, and markedly inhibited tumor growth in vivo. Remarkably, iEVs-335 mediated transcriptional effects that persisted in tumors after 60 days post orthotopic implantation. Genome-wide RNASeq analysis of cancer cells treated in vitro with iEVs-335 showed the regulation of a discrete number of genes only, without broad transcriptome perturbations. This new technology may be ideally suited for therapies aimed to restore tumor suppressor miRNAs in cancer cells, disrupting the oncogenic program established after escape from miRNA control

The association of periodontal diseases with metabolic syndrome and obesity

Periodontitis is a multifactorial chronic inflammatory disease associated with dysbiotic plaque biofilms and characterized by progressive destruction of the tooth‐supporting apparatus. Globally, it is estimated that 740 million people are affected by its severe form. Periodontitis has been suggested to be linked to obesity and metabolic syndrome. Obesity, defined as excessive fat accumulation, is a complex multifactorial chronic inflammatory disease, with a high and increasing prevalence. Metabolic syndrome is defined as a cluster of obesity, dyslipidemia, hypertension, and dysglycemia. Obesity, metabolic syndrome and periodontitis are among the most common non‐communicable diseases and a large body of evidence from epidemiologic studies supports the association between these conditions. Extensive research has established plausible mechanisms to explain how these conditions can negatively impact each other, pointing to a bidirectional adverse relationship. At present there is only limited evidence available from a few intervention studies. Nevertheless, the global burden of periodontitis combined with the obesity epidemic has important clinical and public health implications for the dental team. In accordance with the common risk factor approach for tackling non‐communicable diseases, it has been proposed that oral healthcare professionals have an important role in the promotion of periodontal health and general well‐being through facilitation of healthy lifestyle behaviours

Don't blame it on the sunshine, don't blame it on the moonlight, don't blame it on good times, blame it on the sociocultural factors

In this issue of Hepatology, Ventura‐Cots and colleagues present their study arguing that colder weather and fewer sunlight hours increase alcohol consumption and thus cause alcoholic cirrhosis (1). “Causality” is a key concept for this study. A recent review on the topic highlighted two nicely articulated definitions provided by Lilienfeld (‘a factor may be defined as a cause of a disease, if the incidence of the disease is diminished when exposure to this factor is likewise diminished’) and Pearl (‘X is a cause of Y if Y listens to X and decides its value in response to what it hears

The amount of periosteal apposition required to maintain bone strength during aging depends on adult bone morphology and tissue‐modulus degradation rate

Although the continued periosteal apposition that accompanies age‐related bone loss is a biomechanically critical target for prophylactic treatment of bone fragility, the magnitude of periosteal expansion required to maintain strength during aging has not been established. A new model for predicting periosteal apposition rate for men and women was developed to better understand the complex, nonlinear interactions that exist among bone morphology, tissue‐modulus, and aging. Periosteal apposition rate varied up to eightfold across bone sizes, and this depended on the relationship between cortical area and total area, which varies with external size and among anatomical sites. Increasing tissue‐modulus degradation rate from 0% to −4%/decade resulted in 65% to 145% increases in periosteal apposition rate beyond that expected for bone loss alone. Periosteal apposition rate had to increase as much as 350% over time to maintain stiffness for slender diaphyses, whereas robust bones required less than a 32% increase over time. Small changes in the amount of bone accrued during growth (ie, adult cortical area) affected periosteal apposition rate of slender bones to a much greater extent compared to robust bones. This outcome suggested that impaired bone growth places a heavy burden on the biological activity required to maintain stiffness with aging. Finally, sex‐specific differences in periosteal apposition were attributable in part to differences in bone size between the two populations. The results indicated that a substantial proportion of the variation in periosteal expansion required to maintain bone strength during aging can be attributed to the natural variation in adult bone width. Efforts to identify factors contributing to variation in periosteal expansion will benefit from developing a better understanding of how to adjust clinical data to differentiate the biological responses attributable to size‐effects from other genetic and environmental factors. © 2012 American Society for Bone and Mineral Research.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/93512/1/1643_ftp.pd

Convergent interviewing : a qualitative diagnostic technique for researchers

Purpose &ndash; This paper aims to widen knowledge of and explore how convergent interviewing can be used to identify key issues within an organization.Design/methodology/approach &ndash; This paper introduces the convergent interviewing technique and describes the method of selecting the interview subjects. The construction of a round of interviews is explained. The content of the interviews is described and the particular probing nature of the questions demanded by the convergent interview process is explained. The ways to analyze the full set of interviews for groupings or categories is also described. The case study example of a broad research question about influences on work behaviors in a local government council is used to illustrate the convergent interviewing technique.Findings &ndash; The key issues revealed by using the technique can be subsequently used for a variety of research and consulting purposes and settings. Convergent interviewing is an effective research method, which conserves resources.Originality/value &ndash; Convergent interviewing enables researchers to determine the most important and/or key issues within a population rather than a full list of issues in an organization or barriers to change in a particular organizational context. <br /