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Background Sepsis is a multi-system syndrome that remains the leading cause of mortality and critical illness worldwide, with hemodynamic support being one of the cornerstones of the acute management of sepsis. We used an ovine model of endotoxemic shock to determine if 0.9% saline resuscitation contributes to lung inflammation and injury in acute respiratory distress syndrome, which is a common complication of sepsis, and investigated the potential role of matrix metalloproteinases in this process. Methods Endotoxemic shock was induced in sheep by administration of an escalating dose of lipopolysaccharide, after which they subsequently received either no fluid bolus resuscitation or a 0.9% saline bolus. Lung tissue, bronchoalveolar fluid (BAL) and plasma were analysed by real-time PCR, ELISA, flow cytometry and immunohistochemical staining to assess inflammatory cells, cytokines, hyaluronan and matrix metalloproteinases. Results Endotoxemia was associated with decreased serum albumin and total protein levels, with activated neutrophils, while the glycocalyx glycosaminoglycan hyaluronan was significantly increased in BAL. Quantitative real-time PCR studies showed higher expression of IL-6 and IL-8 with saline resuscitation but no difference in matrix metalloproteinase expression. BAL and tissue homogenate levels of IL-6, IL-8 and IL-1β were elevated. Conclusions This data shows that the inflammatory response is enhanced when a host with endotoxemia is resuscitated with saline, with a comparatively higher release of inflammatory cytokines and endothelial/glycocalyx damage, but no change in matrix metalloproteinase levels.

Urbanization grows rapidly in Malaysia and has known to have several negative impacts. As development intensifies, water runs rapidly into rivers and less filters through the soil, contributes to the congestion of the stormwater drainage system that leads to the flash flood problem. Waste and pollution transported by stormwater also posed environmental problems, thus several open drain systems were introduced to improve it. However, some of those open drainage systems contributes to more pollutions and worsened the quality of life of the urban dwellers in Malaysia. Several approaches with different concepts have been developed, including the Best Management Practices (BMPs), Low Impact Development (LID), Water Sensitive Urban Design (WSUD), Sustainable Urban Drainage Systems (SUDS), Innovative Stormwater Management and the Green Stormwater Infrastructure (GSI). This paper proposed the potential system that gives minimal impact to the environment while improving the water filtration and flood control system in the urban areas. The GSI system can effectively address water environment issues caused by traditional stormwater drainage systems. Research focuses on the development and application of an integrated GSI storage used in urban areas adapted to flood risk with the used of bio-composite material. A lab scale system was developed to study the performance of bio-composite materials and the design of inner storage as an infiltrator as runoff decelerator. Results showed that the used of rice husk and coconut fibre as an infiltrator improved the quality of rainwater. The integrated GSI that was designed to have an inner storage also elongates the surface runoff time. It is expected that the proposed design of eco-friendly integrated storage for drainage system could prevent ponding and at the same time the contaminated flow will be filtrated by the embedded bio-composite materials before entering the water bodies.

This study investigates the effect of corrosion behaviour of stainless steel before and after carburizing process. All samples were prepared based on the testing specification requirement and the chemical compositions of the stainless steel were obtained using spectrometer tester. Samples were then undergoing pack carburizing process by adding 50g of carbon powder as the carburizing agent. Then the samples were heated at 900 °C and 950 °C for 8 hours. To obtain corrosion rate, weight loss test was conducted and the samples were immersed in three different solutions which were distilled water, hydrochloric acid and sodium chloride. Hardness and density test were employed to measure the physical properties of the ASTM 304 stainless steel. The microstructures of all samples were observed using Olympus BX41M optical microscope. The resulting phases after each heat treatment were tested by x-ray diffraction (XRD) tester. The percentage of corrosion values, determined from this technique, showed fairly good agreement. Carburizing process produced a carburizing layer improved mechanical properties and corrosion resistance abilities

Solvent-producing Clostridium acetobutylicum was purified and used in an acetone-butanol-ethanol (ABE) fermentation process. The objective of this study is to design a fermentation medium for the synthesis of butanol and determine the ideal glucose concentration for appropriate microbe ingestion. The fermentation medium was incubated at 37 °C for up to 90 h before inoculation while being sparged with nitrogen gas under anaerobic conditions. Based on the optical density of fermentation media, the growth rate was also monitored. At 60 g/L of glucose, which was the optimum condition for fermentation, the process followed a log phase pattern until the death phase, with the largest growth taking place between 10 h and 50 h after incubation. The C. acetobutylicum steadily consumed the glucose content, reaching its maximal consumption with only around 12 g/L remaining. In contrast to acetone and ethanol, which produced the highest concentrations at 6.4 g/L and 5.2 g/L, respectively, butanol productions were seen appropriately, with the greatest concentration yielding 11.2 g/L of butanol. This shows that C. acetobutylicum expressed its active metabolism for up to 60 g/L and further increase of glucose content will deteriorate the performance of butanol production.

Long-term nicotine intake is associated with an increased risk of myocardial damage and dysfunction. However, it remains unclear whether targeting mitochondrial reactive oxygen species (ROS) prevents nicotine-induced cardiac remodeling and dysfunction. This study investigated the effects of mitoTEMPO (a mitochondria-targeted antioxidant), and resveratrol (a sirtuin activator) , on nicotine-induced cardiac remodeling and dysfunction. Sprague–Dawley rats were administered 0.6 mg/kg nicotine daily with 0.7 mg/kg mitoTEMPO, 8 mg/kg resveratrol, or vehicle alone for 28 days. At the end of the study, rat hearts were collected to analyze the cardiac structure, mitochondrial ROS level, oxidative stress, and inflammation markers. A subset of rat hearts was perfused ex vivo to determine the cardiac function and myocardial susceptibility to ischemia–reperfusion injury. Nicotine administration significantly augmented mitochondrial ROS level, cardiomyocyte hypertrophy, fibrosis, and inflammation in rat hearts. Nicotine administration also induced left ventricular dysfunction, which was worsened by ischemia–reperfusion in isolated rat hearts. MitoTEMPO and resveratrol both significantly attenuated the adverse cardiac remodeling induced by nicotine, as well as the aggravation of postischemic ventricular dysfunction. Findings from this study show that targeting mitochondrial ROS with mitoTEMPO or resveratrol partially attenuates nicotine-induced cardiac remodeling and dysfunction.

Increased exposure to nicotine contributes to the development of cardiac dysfunction by promoting oxidative stress, fibrosis, and inflammation. These deleterious events altogether render cardiac myocytes more susceptible to acute cardiac insults such as ischemia-reperfusion (I/R) injury. This study sought to elucidate the role of angiotensin II type I (AT1) receptors in cardiac injury resulting from prolonged nicotine administration in a rat model. Male Sprague-Dawley rats were given nicotine (0.6 mg/kg ip) for 28 days to induce cardiac dysfunction, alone or in combination with the AT1 receptor antagonist, irbesartan (10 mg/kg, po). Vehicle-treated rats were used as controls. Rat hearts isolated from each experimental group at study endpoint were examined for changes in function, histology, gene expression, and susceptibility against acute I/R injury determined . Rats administered nicotine alone exhibited significantly increased cardiac expression of angiotensin II and angiotensin-converting enzyme (ACE) in addition to elevated systolic blood pressure (SBP) and heart rate. Furthermore, nicotine administration markedly reduced left ventricular (LV) performance with concomitant increases in myocardial oxidative stress, fibrosis, and inflammation. Concomitant treatment with irbesartan attenuated these effects, lowering blood pressure, heart rate, oxidative stress, and expression of fibrotic and inflammatory genes. Importantly, the irbesartan-treated group also manifested reduced susceptibility to I/R injury . These findings suggest that AT1 receptors play an important role in nicotine-induced cardiac dysfunction, and pharmacological approaches targeting cardiac AT1 receptors may thus benefit patients with sustained exposure to nicotine.

Background Rheumatoid arthritis (RA) is a chronic disease influenced by genetic and environmental factors, with viral infections potentially influencing the immune system and increasing the risk of autoimmune diseases like RA. This study investigated the relationship between exposure to chikungunya and dengue infections, indicated by the presence of arboviral IgG antibodies, and risk of developing RA dichotomized by anti‐citrullinated protein antibody (ACPA) status. Methods Serum samples from the Malaysian Epidemiological Investigation of Rheumatoid Arthritis (MyEIRA) population‐based case‐control study involving 1235 RA cases and 1625 controls were assayed for IgG antibodies against chikungunya and dengue viruses. Positive results indicate previous exposure to the studied arboviral infections. Logistic regression and Mann–Whitney U test were performed to estimate the risk of developing ACPA‐positive/ACPA‐negative RA. Results We observed a low frequency of chikungunya IgG antibodies and a high frequency of dengue IgG antibodies in the overall RA cases and controls. No direct association was observed between previous exposure to chikungunya/dengue infection and risk of future RA in overall RA cases and controls. However, analysis by ethnicity showed a decreased risk for ACPA‐positive RA in chikungunya IgG antibody positive subjects of Malay (odds ratio [OR] = 0.38, 95% confidence interval [CI] = 0.16–0.90, p < 0.05) and Chinese origins (OR = 0.12, 95% CI = 0.01–0.93, p < 0.05). Additionally, we observed a decreased risk of ACPA‐positive RA in Indian among persons with positive dengue IgG antibody status (OR = 0.60, 95% CI = 0.38–0.95, p < 0.05). No significant association was observed between chikungunya/dengue infection exposures and risk of ACPA‐negative RA. Conclusion This study found no overall association between chikungunya or dengue exposure, and the risk for developing RA. The Malaysian Epidemiological Investigation of Rheumatoid Arthritis population‐based case‐control study examined whether prior exposure to chikungunya and dengue viruses (via IgG seropositivity) is associated with rheumatoid arthritis (RA) risk, stratified by anti‐citrullinated protein antibody (ACPA) status. No overall association was found, but a reduced risk of ACPA‐positive RA was observed in specific ethnic groups. Key points With the availability of data from a large Asia population‐based case control study, namely the Malaysian Epidemiology Investigation of Rheumatoid Arthritis (MyEIRA), we investigated the relationships between anti‐arboviral antibodies (i.e., chikungunya and dengue) and different subsets of rheumatoid arthritis (RA), defined by anti‐citrullinated protein antibody (ACPA) status, and the risk of developing RA. In this study, low frequency of chikungunya IgG antibodies and high frequency of dengue IgG antibodies were found in both RA cases and controls. Ethnicity stratification analysis revealed decreased risk of developing ACPA‐positive RA in the Malays and Chinese with positive chikungunya IgG antibodies, and in Indians with positive dengue IgG antibodies, respectively. This study found no overall association between chikungunya or dengue exposure, and the risk for developing RA, whilst the inverse associations observed in RA with positive anti‐arboviral antibodies are in‐line with certain other studies investigating exposures to viral infections and RA risk.

Introduction: A regenerative strategy employing extracellular matrix (ECM)-based biomaterials and stem cells provide a better approach to mimicking the three-dimensional (3D) microenvironment of intervertebral disc for endogenous tissue regeneration. However, there is currently limited understanding regarding the human Wharton Jelly derived-mesenchymal stem cells (hWJ-MSCs) towards nucleus pulposus (NP)-like cells. Our study focused on the development of 3D bioengineered hydrogel based on the predominant ECM of native NP, including type II collagen (COLII) and hyaluronic acid (HA), which aims to tailor the needs of the microenvironment in NP. Methods: We have fabricated a 3D hydrogel using from COLII enriched with HA by varying the biomacromolecule concentration and characterised it for degradation, stability and swelling properties. The WJ-MSC was then encapsulated in the hydrogel system to guide the cell differentiation into NP-like cells. Results: We successfully fabricated COLII hydrogel (2 mg/ml) and HA 10 mg/ml at a weight ratio of HA and COLII at 1:9 and 4.5:9, and both hydrogels physically maintained their 3D sphere-shaped structure after complete gelation. The higher composition of HA in the hydrogel system indicated a higher water intake capacity in the hydrogel with a higher amount of HA. All hydrogels showed over 60% hydrolytic stability over a month. The hydrogel showed an increase in degradation on day 14. The hWJ-MSCs encapsulated in hydrogel showed a round morphology shape that was homogenously distributed within the hydrogel of both groups. The viability study indicated a higher cell growth of hWJ-MSCs encapsulated in all hydrogel groups until day 14. Discussion: Overall, our findings demonstrate that HA/COLII hydrogel provides an optimal swelling capacity, stability, degradability, and non-cytotoxic, thus mimics the NP microenvironment in guiding hWJ-MSCs towards NP phenotype, which is potentially used as an advanced cell delivery system for intervertebral disc regeneration.

Gynura procumbens (Lour.) Merr. (GP) has been reported in previous studies to possess antihyperlipidaemic, antioxidative, and cardioprotective properties. This study was aimed to determine the effect of standardised 80% ethanol extract of GP on lipid profiles and oxidative status of hypercholesterolemic rats. Postmenopausal (PM) Sprague-Dawley rats were ovariectomised and fed with 2% cholesterol diet fortified with five times heated palm oil to develop hyperlipidaemia status. Two doses of the extract (250 and 500 mg/kg) and atorvastatin (10 mg/kg) were administered once daily via oral gavage for 24 weeks. Systolic blood pressure (SBP) was increased during the first month in the postmenopausal group and decreased with GP supplementation. Lipid droplets accumulation was shown at the tunica media (TM) area of the aorta in the postmenopausal group and reduced with GP supplementation. Total cholesterol (TC), total triglycerides (TG), low-density lipoprotein (LDL), and malondialdehyde (MDA) levels increased (p<0.05) at 3 and 6 months in the postmenopausal group and were reduced with GP supplementation. GP also increased high-density lipoprotein (HDL) level in the postmenopausal group. Superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) activities were reduced in the postmenopausal group compared to control in the sham group but increased (p<0.05) with GP supplementation. The results showed that the higher dose of GP (500 mg/kg) gave better effect. GP has the ability to reduce oxidative stress and prevent membrane cell damage through antioxidant enzyme activity modification and lipid profile changes in postmenopausal rats related to atherosclerosis.

Wound patches are essential for wound healing, yet developing patches with enhanced mechanical and biological properties remains challenging. This study aimed to enhance the mechanical and biological properties of polyurethane (PU) by incorporating magnesium chloride (MgCl ) into the patch. The composite patch was fabricated using the electrospinning technique, producing nanofibers from a mixture of PU and MgCl solutions. The electrospun PU/MgCl was then evaluated for various physico-chemical characteristics and biological properties to determine its suitability for wound healing applications. Tensile strength testing showed that the mechanical properties of the composite patch (10.98 ± 0.18) were significantly improved compared to pristine PU (6.66 ± 0.44). Field scanning electron microscopy (FESEM) revealed that the electrospun nanofiber patch had a smooth, randomly oriented non-woven structure (PU - 830 ± 145 nm and PU/MgCl - 508 ± 151 nm). Fourier infrared spectroscopy (FTIR) confirmed magnesium chloride's presence in the polyurethane matrix via strong hydrogen bond formation. Blood compatibility studies using coagulation assays, including activated partial thromboplastin time (APTT), prothrombin time (PT), and hemolysis assays, demonstrated improved blood compatibility of the composite patch (APTT - 174 ± 0.5 s, PT - 91 ± 0.8s, and Hemolytic percentage - 1.78%) compared to pristine PU (APTT - 152 ± 1.2s, PT - 73 ± 1.7s, and Hemolytic percentage - 2.55%). Antimicrobial testing showed an enhanced zone of inhibition (Staphylococcus aureus - 21.5 ± 0.5 mm and Escherichia coli - 27.5 ± 2.5 mm) compared to the control, while cell viability assays confirmed the non-cytotoxic nature of the developed patches on fibroblast cells. The study concludes that adding MgCl to PU significantly improves the mechanical, biological, and biocompatibility properties of the patch. This composite patch shows potential for future wound healing applications, with further studies needed to validate its efficacy in-vivo.