Chronic organic arsenic induced liver ultra structural damage

Introduction: Inorganic arsenic is one of the environmental toxins that has been associated with increased risk of cardiovascular diseases and vascular contributions to liver diseases. It has generally been thought to be more toxic than organic arsenic. In human liver, inorganic arsenic promotes vascular remodelling, portal fibrosis and hypertension. The purpose of the current study was to determine whether chronic exposure to organic arsenic impair liver ultrastructure as in inorganic arsenic exposure. Materials and Methods: Twenty eight male SpragueDawley rats were divided into 2 groups with their own control group. They received oral intubation of monosodium- methylarsonate (MSMA) at 63.30 mg/kg body weight for 4 and 6 months duration respectively while the control groups received distilled water. The liver of euthanized rats were perfused- fixed with glutaraldehyde for transmission electron microscopy processing. Results: TEM revealed a marked reduction in the number of mitochondria in both treatment groups. Some typical features of apoptosis are present with pyknotic nuclei of hepatocytes and disintegrated hepatic cytoplasm in 4- month groups. The microvilli of hepatocyte are almost completely absent with the presence of many fibre bundles (collagen fibres) widening the space of Disse. In 6-month treatment group, disintegrated cytoplasms are more prominent with degrading mitochondria of varying stages. Liver sinusoidal endothelial cells (LSEC) of 6-month treatment group are noted to have chromatin condensation with few caveolae seen. Conclusion: Chronic exposure of MSMA leads to necrotic changes of hepatocytes and apoptotic changes in LSEC and collagenisation in the space of Disse

Liver Sinusoidal Endothelial Cell (LSEC) isolation following a liver perfusion technique

Introduction: Liver perfusion has been the standard method to digest and isolate liver cells including liver sinusoidal endothelial cells (LSEC). Poor cannulating skills through portal vein results in a waste of animal resource. Familiarization of both liver perfusion technique and adhering strictly to aseptic technique during cell handling ensure high cell yield, minimum morphology disruption and cell contamination. We aimed to present a method of liver perfusion procedure followed by the isolation of LSEC. Materials and method: The study was conducted with the approval of IACUC committee. Seven Sprague Dawley rats underwent these procedures under anaesthesia. Liver perfusion was done as previously described. Briefly, LSEC were isolated by liberase enzyme perfusion of the liver, isopycnic sedimentation in a two- step Percoll gradient and selective adherence. The purification and cultivation of LSEC was evaluated by light and electron microscopy. Results: Purity and viability of LSEC after selective adherence was 80.5 ± 3.5% and ≥ 95 %, respectively. The average concentration of the cells ranged from 32 - 75 x 106 per 400 gm rat. After 8 hours of culture, LSEC monolayers were contaminated with less than 5% of other cells. Conclusion: This method is reliable and reproducible for the isolation of LSEC to enable the study of structure and function of these cells in vitro. However, improvement on the perfusion skills and isolation technique are vital to ensure better cell purity

Hydrophobic ceramic membrane for membrane distillation: A mini review on preparation, characterization, and applications

Membrane distillation (MD) is one of the emerging separation technologies with extremely high separation factor, especially in desalination application. MD utilizes the hydrophobic membrane which only allows the passage of vapor through the membrane pores. Recent years have witnessed great progress in the development of hydrophobic ceramic membranes for MD applications due to their superior properties over the polymeric counterparts. However, ceramic membranes are hydrophilic in nature; hence, membrane surface modification process is required to acquire hydrophobic properties for MD applications. Direct grafting using silane agents is the most widely used ceramic membrane hydrophobization method. Hence, this mini review provides a complete summary of the research progress on the preparation and characterization of the hydrophobic ceramic membranes through silane agent grafting, as well as their applications in MD. Finally, future research directions have also been addressed

Leucocytic DNA methylation of Interleukin-6 promoter reduction in pre-hypertensive young adults

Background: Pre-hypertension is associated with increased risk of cardiovascular disease. Chronic inflammation plays an important role in the pathophysiology of essential hypertension, with epigenetic dysregulation involvement. Nevertheless, the role of DNA methylation in prehypertensive state is unknown. The aim of this study was to investigate the association between DNA methylation level of interleukin-6 (IL-6) promoter in pre-hypertensive (PreHT) and normotensive (NT) young adults. Methods: A total of 80 NT and 80 PreHT healthy subjects aged between 18–45 years were recruited in Kuantan, Pahang, Malaysia using an observational cross-sectional study approach. DNA methylation level of IL-6 promoter in peripheral leukocytes were measured using bisulphite conversion and MethyLight assay. Results: There was no significant difference in age between NT and PreHT (P = 0.655). The mean blood pressure was 110(8)/73(5) mmHg in NT and 125(7)/82(5) mmHg in PreHT subjects. The IL-6 promoter methylation level was significantly lower in PreHT compared to NT subjects (P < 0.001). Conclusion: The current study demonstrates that hypomethylation of IL-6 promoter was associated with pre-hypertension in young adults. Thus, IL-6 methylation could be used as an early indicator for predicting hypertension and related risk of cardiovascular diseases in prehypertensive subjects. Gene expression and longitudinal studies are warranted to examine the methylation effect on IL-6 expression over time

Removal of As(III) and As(V) from water using green, silica-based ceramic hollow fibre membranes via direct contact membrane distillation

Arsenite [As(III)] and arsenate [As(V)] removal by direct contact membrane distillation (DCMD) using novel hydrophobic green, silica-based ceramic hollow fibre membranes derived from agricultural rice husk was investigated in this work. The green ceramic hollow fibre membranes were prepared from amorphous (ASHFM) and crystalline (CSHFM) silica-based rice husk ash and modified to be hydrophobic via immersion fluoroalkylsilane (FAS) grafting of 1H,1H,2H,2H-perfluorodecyltriethoxysilane. Superhydrophobic contact angle values up to 157° and 161° were obtained for ASHFM and CSHFM, respectively. Remarkably, the membrane surface morphology mimicked a look-alike lotus-leaf structure with decrement in pore size after grafting via the silane agent for both membranes. The effect of arsenic pH (3–11), arsenic concentration (1–1000 ppm) and feed temperature (50–80 °C) were studied and it was found that feed temperature had a significant effect on the permeate flux. The hydrophobic CSHFM, with a flux of 50.4 kg m−2 h−1 for As(III) and 51.3 kg m−2 h−1 for As(V), was found to be the best of the tested membranes. In fact, this membrane can reject arsenic to the maximum contaminant level (MCL) limit of 10 ppb under any conditions, and no swelling mechanism of the membranes was observed after testing for 4 hours

Identification of haptoglobin as a potential biomarker in young adults with acute myocardial infarction by proteomic analysis

Background: Acute myocardial infarction (AMI) molecular research in young adults is still limited. The aim of this study is to identify AMI proteomic biomarker(s) in young adults. Methods: This study comprised of two phases namely discovery and verification. In the discovery phase, proteins in the pooled plasma samples from young male adults between 18 and 45 years (10 AMI patients and 10 controls) were separated using two-dimensional electrophoresis. The protein spots that were expressed differently in the AMI patients were identified via matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry. The plasma concentrations of these proteins were quantified using enzyme-linked immunosorbent assay during the verification phase (40 AMI patients and 80 controls). Results: Haptoglobin (Hp), apolipoprotein AI (Apo AI) and apolipoprotein AIV (Apo AIV) were up-regulated in the discovery phase. In the verification phase, the plasma concentration of Hp was significantly higher in AMI patients than the controls (P < 0.001). Logistic regression showed an association between Hp and AMI in young adults (odds ratio [OR] = 1.016, 95% CI: 1.002– 1.030, P = 0.025) independent of other AMI risk factors. Hp was significantly correlated with high sensitivity C-reactive protein (hs-CRP) (r = 0.424, P < 0.001). Conclusion: In young adults with AMI, plasma Hp concentrations were elevated and it is independently associated with AMI. A positive correlation with hs-CRP suggests Hp could be a potential biomarker of AMI in young adults

High strength and antifouling metakaolin-based ceramic membrane for juice clarification

Key lime, watermelon, and kiwifruit juices were successfully clarified by using a novel high strength and antifouling metakaolinbased ceramic membranes prepared via combination of phase inversion and sintering technique. The fabricated membrane was characterized by utilizing scanning electron microscopy (SEM) analysis, three-point bending strength, juice permeation, and fouling behavior analysis. In this work, the fouling behavior of the membrane was studied using Darcy’s law for cross-flow filtration system. Analysis of the fouling mechanism revealed that the membranes’ fouling was most influenced by the cake filtration mechanism and can be solved easily by applying high operating pressure. Membranes prepared at a sintering temperature of 1300 °C were found to be optimum membranes for juice clarification as it possessed excellent mechanical strength (176.8 MPa) and pure water flux of 273 L/m2 h at 500 kPa. Interestingly, it was also found that the membrane could endure high operating pressure up to 700 kPa, which consequently solved the fouling issue. Thereby, the precious juice properties, such as total suspended solid (TSS), pH, acidity, and density for all juices, were found to be almost unaffected

Novel hydroxyapatite-based bio-ceramic hollow fiber membrane derived from waste cow bone for textile wastewater treatment

Industrial textile wastewater is toxic due to the presence of recalcitrant color pigments and poisonous heavy metals. In this study, the hydroxyapatite (HAp)-based bio-ceramic hollow fiber membranes (h-bio-CHFM) were developed via the combined phase inversion and sintering technique. It was found that the properties of the developed h-bio-CHFMs were greatly affected by the HAp content of the ceramic suspension, and sintering temperature. The h-bio-CHFM with the sintering temperature of 1200 degrees C exhibited the long rod-shaped HAp particles and the smallest pore size (0.013 mu m). High removals of color (99.9%), COD (80.1%), turbidity (99.4%) and conductivity (30.1%) were achieved using the h-bio-CHFM sintered at 1200 degrees C with stable high flux of 88.3 L/m(2)h. Remarkably, the h-bio-CHFM sintered in the temperature range of 1000-1200 degrees C also demonstrated excellent adsorption ability towards heavy metals with 100% removals. The results of this study show the potential of the h-bio-CHFM for the efficient industrial textile wastewater treatment applications

Effect of CFRP plate length on flexural behavior of GFRP reinforced concrete beam strengthening

This research investigates the effect of CFRP plate length on flexural behaviour of GFRP strengthened reinforced concrete beam. CFRP plate was placed on the bottom of the beam to act as tension reinforcement. Ten beams were tested, largely divided into over designed and under designed reinforced beams. Each group had one steel reinforced concrete beam, one GFRP reinforced concrete beam and three GFRP reinforced concrete beam with different length of CFRP plate at the bottom of beam. Tested parameters included flexural strength, stress–strain relationship and deflection. Results indicated that all strengthened beams had improved structural performance where the maximum flexural strength increased by 102% and maximum deflection reduced by 35%. The CFRP plate can significantly improve the load-bearing capacity of strengthened GFRP concrete beams

High prevalence of vitamin D insufficiency and its association with BMI-for-age among primary school children in Kuala Lumpur, Malaysia

<p>Abstract</p> <p>Background</p> <p>Deficiencies of micronutrients can affect the growth and development of children. There is increasing evidence of vitamin D deficiency world-wide resulting in nutritional rickets in children and osteoporosis in adulthood. Data on the micronutrient status of children in Malaysia is limited. The aim of this study was to determine the anthropometric and micronutrient status of primary school children in the capital city of Kuala Lumpur.</p> <p>Methods</p> <p>A cross sectional study of primary aged school children was undertaken in 2008. A total of 402 boys and girls aged 7-12 years, attending primary schools in Kuala Lumpur participated in the study. Fasting blood samples were taken to assess vitamin D [as 25(OH)D], vitamin B₁₂, folate, zinc, iron, and ferritin and haemoglobin concentrations. Height-for-age and body mass index for age (BMI-for-age) of the children were computed.</p> <p>Results</p> <p>Most of the children had normal height-for-age (96.5%) while slightly over half (58.0%) had normal BMI-for-age. A total of 17.9% were overweight and 16.4% obese. Prevalence of obesity was significantly higher among the boys (25%) than in the girls (9.5%) (χ²= 22.949; <it>P </it>< .001). Most children had adequate concentrations of haemoglobin, serum ferritin, zinc, folate and vitamin B₁₂. In contrast, 35.3% of the children had serum 25(OH)D concentrations indicative of vitamin D deficiency(≤37.5 nmol/L) and a further 37.1% had insufficiency concentrations (> 37.5-≤50 nmol/L). Among the boys, a significant inverse association was found between serum vitamin D status and BMI-for-age (χ²= 5.958; <it>P </it>= .016).</p> <p>Conclusions</p> <p>This study highlights the presence of a high prevalence of sub-optimal vitamin D status among urban primary school children in a tropical country. In light of the growing problem of obesity in Malaysian children, these findings emphasize the important need for appropriate interventions to address both problems of obesity and poor vitamin D status in children.</p