Mechanisms and Therapeutic Targets of Cardiac Regeneration: Closing the Age Gap

While a regenerative response is limited in the mammalian adult heart, it has been recently shown that the neonatal mammalian heart possesses a marked but transient capacity for regeneration after cardiac injury, including myocardial infarction. These findings evidence that the mammalian heart still retains a regenerative capacity and highlights the concept that the expression of distinct molecular switches (that activate or inhibit cellular mechanisms regulating tissue development and regeneration) vary during different stages of life, indicating that cardiac regeneration is an age-dependent process. Thus, understanding the mechanisms underpinning regeneration in the neonatal-infarcted heart is crucial to develop new treatments aimed at improving cardiovascular regeneration in the adult. The present review summarizes the current knowledge on the pathways and factors that are known to determine cardiac regeneration in the neonatal-infarcted heart. In particular, we will focus on the effects of microRNA manipulation in regulating cardiomyocyte proliferation and regeneration, as well as on the role of the Hippo signaling pathway and Meis1 in the regenerative response of the neonatal-infarcted heart. We will also briefly comment on the role of macrophages in scar formation of the adult-infarcted heart or their contribution for scar-free regeneration of the neonatal mouse heart after myocardial infarction. Although additional research is needed in order to identify other factors that regulate cardiovascular regeneration, these pathways represent potential therapeutic targets for rejuvenation of aging hearts and for improving regeneration of the adult-infarcted heart

On Walsh-Fourier Bispectral Analysis

In this paper we define the Walsh-Fourier bispectral density and establish a statistical methodology for bispectral analysis of integer valued time series. The theoretical properties and results pertaining to the definition and estimation of the Walsh-Fourier bispectral density are obtained. Many of the results we obtain have their analogues in the conventional Fourier frequency domain. We present simulation results of Walsh Fourier bispectral density for linear and bilinear integer valued time series models

Analysis of the Effect of Simultaneous Melt Shearing and Cooling on Grain Formation and Rheology of A356 Aluminum Alloy

Despite the dozens of earlier research verifications, the contribution of shearing of molten metallic alloys during their solidification to grain formation is still ambiguous. Also, modeling of this phenomenon has received very little attention. Experiments were conducted in this study to investigate the effect of the shear rate on the density, size, and shape factor of the formed grains up to a solid fraction of 0.15 for the solidifying A356 aluminum alloy in the coaxial cylinder viscometer. The rheology of the formed semisolid slurry was studied as well. Results exhibited morphological evolution and grain refinement. The grain number density increased from 5 × 108 m−3 in the absence of melt shearing to reach 4 × 109 m−3 at the shear rate of 250 s−1. Also, the shape factor was improved to reach 0.78. Based on the experimental investigations, the grain number density under shearing was correlated to the shear rate and the grain number density in the absence of shearing via an empirical formula. A shear-dependent grain multiplication factor was deduced. The alloy exhibited a shear-thinning behavior where the viscosity obeyed the power law with a constant and an exponent of 0.9264 and 0.468, respectively. Moreover, the measured data were fitted to several proposed viscosity models and the model of Hirai et al. showed the best fit; therefore, it was recommended for predicting the viscosity of semisolid slurries

Vulnerable Older Populations without Special Health Care in Egypt: A need for Assessment & Reform / كبار السن الذين يفتقرون إلى الرعاية الصحية المتخصصة في مصر: متطلبات التقييم والإصلاح

The older population in Egypt needs a special healthcare system to fulfill its needs and expectations. Nowadays, the older people live longer than before due to the improvement of healthcare services. That leads to an increase in the number of older people and creates a pressure on resources especially with the limited resources in Egypt. Urbanization and the change in the Egyptian demographics is exacerbating the problem. Egypt now is becoming a nation of dignified older citizens that need additional care and special attention. A number of policies and reforms have already been discussed but never thoroughly analyzed. Some policies alternatives to the issue are discussed within this paper, and tangible solutions highlighted

Irritable bowel syndrome: prevalence, risk factors in an adult Lebanese population

Abstract Background Very few studies report on the prevalence of irritable bowel syndrome (IBS) and its correlates in the Middle East. This study investigated Irritable Bowel Syndrome (IBS) prevalence in a sample of Lebanese adult individuals and associated demographic and behavioral lifestyle factors. Methods This is an observational population-based study. The target population is working Lebanese adults, eighteen-to-sixty five years old. The sample was selected from a convenience population of bank employees in different geographical areas in Lebanon. The study participants completed an anonymous self-administered questionnaire, to collect data on their socio-demographic, behavioral and life style characteristics, and diagnostic questions following Rome III criteria to assess IBS occurrence. The difference in IBS prevalence by socio-demographic characteristics, smoking, alcohol consumption, and physical activity was assessed by using the Chi-square test. Logistic regression adjusted odds ratios were used to investigate the association between risk factors and IBS. Results Data was collected from 553 individuals and consisted of 52.8% females (mean age 35.9 years, SD = 11.9) and 47.2% males (mean age = 36.1 years, SD = 10.3). The prevalence of IBS in the study population according to Rome III criteria was 20.1%. The bivariate analysis indicated that being younger than 30 years old, a female, an ever water pipe smoker, an ever alcohol consumer are significantly associated with a higher prevalence of IBS. Educational level, cigarettes smoking and physical exercise were not significantly associated with IBS occurrence. The logistic regression adjusted odds ratio showed that females were 1.67 times more likely to have IBS than males (P˂ 0.05). The participants aged less than 30 years old were at a higher risk of having IBS (P˂ 0.01). Those who ever smoked waterpipe were 1.63 times more likely to have IBS than those who never smoked waterpipe (P˂ 0.05). Those who were ever alcohol drinkers were twice as likely to have IBS than never-drinkers (P˂ 0.01). Conclusion New data on the high prevalence of IBS in an adult population in Lebanon has been reported. This is also the first study to investigate and show an association of waterpipe smoking and IBS. Further longitudinal studies are warranted to determine whether this association is causal