Triple fluorochrome labeling of cochlear bone growth.

A new technique is described which measures the extent and time course of intracochlear bone formation after cochlear implantation in an experimental animal model. A series of fluorescent histochemical markers is used to delineate the amount of intracochlear bone deposition during specified time periods.     

Atrial function in the Fontan circulation: comparison with invasively assessed systemic ventricular filling pressure

The International Journal of Cardiovascular Imaging - Abnormal atrial mechanics in biventricular circulations have been associated with elevated left heart filling pressures. Similar associations...     

Effect of 3D-microstructure of bioabsorbable PGA:TMC scaffolds on the growth of chondrogenic cells

Various biomaterial scaffolds have been investigated for cartilage tissue engineering, although little attention has been paid to the effect of scaffold microstructure on tissue growth. Non-woven, fibrous, bioabsorbable scaffolds constructed from a copolymer of glycolide and trimethylene carbonate with varying levels of porosity and pore size were seeded with mesenchymal stroma cells with a chondrogenic lineage. Scaffolds and media were evaluated for both cell and extracellular matrix organization and content after up to 28 days of culture in a spinner flask. Analysis of DNA and glycosaminoglycan contents showed that the most porous of the three scaffold types, with a porosity of 81% and a porometry determined mean flow pore diameter of 54 microm, supported the most rapid proliferation of cells and accumulation of extracellular matrix. Analysis of the high porosity scaffold system, using Western Blot and immunohistochemistry confirmed the presence of collagen type II and absence of collagen type I, and demonstrated cells with a chondrocyte morphology with aggrecan and collagen II accumulation attached to the scaffolds. It was concluded that the 3D-microstructural characteristics of the scaffold (interconnecting porosity and pore size) play an important role in proliferation and phenotype of chondrogenic cells and accumulation of extracellular matrix molecules.     

Bacterial bioactive metabolites as therapeutic agents: From production to action

Bacterial metabolites are one of the primary sources of drugs that we currently use to treat several diseases. However, bacterial drug discovery and development is a challenging and time-consuming process, and the emergence of new diseases and the development of resistance to currently available drugs demand the discovery of new metabolites with better biological activities. The new advancements in microbial technology, omics, genome and metabolic engineering, synthetic biology and the interdisciplinary approach of these fields overcome the hurdles in drug discovery and heterologous synthesis from bacteria. The gut microbiome performs a vital role in sustaining human health and aids in tackling various diseases. The metabolites produced by the gut microbiome act as an energy source for colon epithelium, maintain pH, help in cell differentiation and induces apoptosis in abnormal cells. The review discusses about the bacterial derived bioactive compounds, advancements and technologies in bacterial synthesis of bioactive sources and genomic and synthetic biology methods for the bioprospecting of bacterial metabolites. Since the gut microbiome relates to colon health, we have also discussed the techniques comprising probiotics, prebiotics, microbiome transplantation, toxins, and bacteriocins capable of preventing and managing colon associated health condition. Future directions in bacterial bioactive metabolite production are also discussed.     

Inflammation as an intermediate pathway in the association between psychosocial stress and obesity

Psychosocial stress is associated with risk of obesity although little is known about stress-induced biological mechanisms of obesity. We examined the potential mediating role of inflammatory processes. Data were collected from a nationally representative sample of 7540 individuals (54% women, mean age 46.8+/-15.4 years), from the Scottish Health Surveys. We calculated risk estimates of obesity for increasing numbers of psychosocial stressors (based on social position, education, psychological distress and marital/partner discord) using logistic regression analyses. Obesity was assessed using body mass index and central obesity using waist circumference. Potential mediators included inflammatory markers (C-reactive protein and fibrinogen) and health behaviours (physical activity, smoking, alcohol, and dietary intake). The unadjusted odds ratio of obesity for three or more psychosocial stressors was 1.81 (95% CI, 1.39-2.36, p<0.001). In multivariate analyses that adjusted for age, gender, health behaviours and inflammatory markers the association between psychosocial stress and obesity was attenuated but remained significant (1.49, 1.11-2.00, p<0.001). Inflammatory markers independently accounted for approximately 25% of the association between stress and obesity. We found similar associations in separate analyses of psychosocial stress and central obesity, although results were confounded by overall obesity. In summary, inflammatory processes appear to be an important intermediate pathway in the association between psychosocial stress and obesity.     

Assessing the WHO 50% Prevalence Threshold in School-Aged Children as Indication for Treatment of Urogenital Schistosomiasis in Adults in Central Nigeria

Preventive chemotherapy with praziquantel is recommended in adults by the World Health Organization when prevalence of schistosomiasis in school-aged children (SAC) is ≥ 50%. This study ascertained the value of this threshold in predicting prevalence and intensity of Schistosoma hematobium (SH) infection in adults in central Nigeria. We evaluated urogenital schistosomiasis prevalence in 1,164 adults: 659 adults in 12 communities where mean hematuria among SAC in 2008 was 26.6% and 505 adults in 7 communities where the mean hematuria among SAC in 2008 was 70.4%. No statistically significant differences were found between the two groups of adults in prevalence of hematuria, prevalence of SH eggs, or intensity of infections. We conclude that, in this setting, the SAC threshold is not useful for treatment decisions in adults. Given the increased risk of subtle morbidity or urogenital schistosomiasis as a risk factor for human immunodeficiency virus (HIV), more liberal treatment of adults with praziquantel is warranted.     

The accumulative effects of modifiable risk factors on inflammation and haemostasis

Various modifiable risk factors have been associated with inflammation and haemostasis, although the accumulative effects have not yet been examined. We therefore explored additive and independent associations of modifiable risk factors (smoking, alcohol, cholesterol, obesity, hypertension, physical activity) with inflammatory (CRP) and haemostatic (fibrinogen) markers. Data were collected from a sample of 7670 healthy asymptomatic participants (45.9% men, aged 46.2+/-15.6 years). A graded increase in the risk of inflammation (CRP> or =3 mg/L) with increasing numbers of modifiable risk factors was demonstrated (odds ratio for > or =4 risk factors=5.09, 95% CI, 3.96-6.55). Similar associations were found in relation to haemostasis. Central adiposity was the strongest independent predictor of inflammation (OR=3.45, 95% CI, 3.07-3.87) although smoking most strongly predicted haemostasis (OR=2.19, 95% CI, 1.94-2.48). These findings suggest that targeting multiple risk factors is likely to have the greatest benefit for cardiovascular prevention.     

Se-methylselenocysteine inhibits phosphatidylinositol 3-kinase activity of mouse mammary epithelial tumor cells <Emphasis Type="Italic">in vitro</Emphasis>

Introduction  

Se-methylselenocysteine (MSC), a naturally occurring selenium compound, is a promising chemopreventive agent against in vivo and in vitro models of carcinogen-induced mouse and rat mammary tumorigenesis. We have demonstrated previously that MSC induces apoptosis after a cell growth arrest in S phase in a mouse mammary epithelial tumor cell model (TM6 cells) in vitro. The present study was designed to examine the involvement of the phosphatidylinositol 3-kinase (PI3-K) pathway in TM6 tumor model in vitro after treatment with MSC.