Neuroprotective effect of guggulipid alone and in combination with aspirin on middle cerebral artery occlusion (MCAO) model of focal cerebral ischemia in rats

This study was designed to test the pre-treatment doses of guggulipid (50?mg/kg), aspirin (100?mg/kg) per orally and co-administration of both drugs for 28 days followed by middle cerebral artery occlusion – a model of focal cerebral ischemia in rats. Middle cerebral artery was occluded for two hours, followed by reperfusion for 22 hours for the induction of focal cerebral ischemia in rats. Neurobehavioral tests like locomotor activity and grip strength tests were performed before sacrificing the animal. After neurobehavioral tests, the animals were sacrificed for the measurement of infarction areas and biochemical estimations in brain. Locomotor activity and grip strength were significantly improved in guggulipid and aspirin pre-treated rats. Guggulipid and aspirin pre-treatment reduced the infarction areas as compared with middle cerebral occluded (MCAO) rats. An elevation of nitrite, thiobarbituric acid reactive substance (TBARS), acetylcholine esterase activity (AchE) and reduction in antioxidant enzymes like superoxide dismutase (SOD), glutathione (GSH) and catalase were observed following MCAO. Pre-treatment with guggulipid and aspirin caused a reduction in TBARS and nitrite levels, AchE, but elevated GSH level, SOD and catalase activities as compared with MCAO rats. The protective effects observed in this study were due to antioxidant, anti-inflammatory and anti-hyperlipidemic properties of guggulipid. The protective effect of guggulipid in cerebral ischemia, that it may have a role in reversing the symptoms and may offer significant neuroprotection in stroke.     

Left ventricular hypertrophy and chronic fluid overload in peritoneal dialysis patients

Purpose

Cardiovascular disease is the leading cause of mortality in dialysis patients with left ventricular hypertrophy (LVH) being an important predictor of mortality. We wanted to determine the prevalence of LVH in peritoneal dialysis (PD) patients and factors contributing to it.

Methods

This is a cross-sectional study assessing LVH using echocardiogram in PD patients. Left ventricular mass index (LVMI) was calculated to determine LVH. Chronic fluid overload (overhydration) was assessed using the body composition monitor, and blood pressure (BP) was measured using 24-h ambulatory BP monitoring.

Results

Thirty-one patients (21 females:10 males, 48.97 ± 14.50 years and dialysis vintage 40.0 ± 28.9 months) were studied. More than two-thirds (77.4 %) were hypertensive, and a third (35.5 %) were diabetic. Baseline data included mean serum albumin (37.34 ± 4.43 g/l), weekly Kt/V (2.02 ± 0.23), residual renal function of 68 (0–880) ml and ultrafiltration of 1,606.9 ± 548.6 ml. Majority of patients (80.6 %) had LVH on echocardiogram with LVMI of 136.5 ± 37.8 g/m² and overhydration of 2.23 ± 1.77 l. Average systolic BP, diastolic BP and mean arterial pressure were 141.2 ± 23.3, 90.8 ± 19.7 and 107.6 ± 19.6 mmHg, respectively. Patients with LVH had a lower serum albumin (p = 0.003), were more overhydrated (p = 0.010) and were on higher number of anti-hypertensive agents (p ≤ 0.001). Predictors of LVMI were overhydration (p = 0.002), the presence of diabetes (p = 0.008) and the number of anti-hypertensive agents used (p = 0.026). However, overhydration (p = 0.007) was the main predictor of LVH on multivariate analysis.

Conclusion

Overhydration is strongly associated with LVH in PD patients.     

Unusual presentation of Sturge-Weber syndrome: Progressive megalencephaly with bilateral cutaneous and cortical involvement

The Sturge Weber syndrome is characterized by developmental delay, seizures in infancy, unilateral cutaneous lesions with ipsilateral leptomeningeal enhancement. We report an unusual presentation of Sturge Weber syndrome with bilateral port wine nevus on the trunk and face along with bilateral cortical involvement in a developmentally normal child with progressive megalencephaly.     

Annatto Tocotrienol Improves Indices of Bone Static Histomorphometry in Osteoporosis Due to Testosterone Deficiency in Rats

This study aimed to evaluate the effects of annatto tocotrienol on indices of bone static histomorphometry in orchidectomized rats. Forty male rats were randomized into baseline (BL), sham (SH), orchidectomized (ORX), annatto tocotrienol-treated (AnTT) and testosterone enanthate-treated (TE) groups. The BL group was sacrificed upon receipt. All rats except the SH group underwent bilateral orchidectomy. Annatto tocotrienol at 60 mg/kg body weight was administered orally daily to the AnTT group for eight weeks. Testosterone enanthate at 7 mg/kg body weight was administered intramuscularly once weekly for eight weeks to the TE group. The rat femurs were collected for static histomorphometric analysis upon necropsy. The results indicated that the ORX group had significantly higher osteoclast surface and eroded surface, and significantly lower osteoblast surface, osteoid surface and osteoid volume compared to the SH group (p < 0.05). Annatto tocotrienol and testosterone enanthate intervention prevented all these changes (p < 0.05). The efficacy of annatto tocotrienol was on par with testosterone enanthate. In conclusion, annatto tocotrienol at 60 mg/kg can prevent the imbalance in bone remodeling caused by increased osteoclast and bone resorption, and decreased osteoblast and bone formation. This serves as a basis for the application of annatto tocotrienol in hypogonadal men as an antiosteoporotic agent.     

The State of Starch/Hydroxyapatite Composite Scaffold in Bone Tissue Engineering with Consideration for Dielectric Measurement as an Alternative Characterization Technique

Hydroxyapatite (HA) has been widely used as a scaffold in tissue engineering. HA possesses high mechanical stress and exhibits particularly excellent biocompatibility owing to its similarity to natural bone. Nonetheless, this ceramic scaffold has limited applications due to its apparent brittleness. Therefore, this had presented some difficulties when shaping implants out of HA and for sustaining a high mechanical load. Fortunately, these drawbacks can be improved by combining HA with other biomaterials. Starch was heavily considered for biomedical device applications in favor of its low cost, wide availability, and biocompatibility properties that complement HA. This review provides an insight into starch/HA composites used in the fabrication of bone tissue scaffolds and numerous factors that influence the scaffold properties. Moreover, an alternative characterization of scaffolds via dielectric and free space measurement as a potential contactless and nondestructive measurement method is also highlighted.     

Optimisation of Shrinkage and Strength on Thick Plate Part Using Recycled LDPE Materials

Achieving good quality of products from plastic injection moulding processes is very challenging, since the process comprises many affecting parameters. Common defects such as warpage are hard to avoid, and the defective parts will eventually go to waste, leading to unnecessary costs to the manufacturer. The use of recycled material from postindustrial waste has been studied by a few researchers. However, the application of an optimisation method by which to optimise processing parameters to mould parts using recycled materials remains lacking. In this study, Response Surface Methodology (RSM) and Particle Swarm Optimisation (PSO) methods were conducted on thick plate parts moulded using virgin and recycled low-density polyethylene (LDPE) materials (100:0, 70:30, 60:40 and 50:50; virgin to recycle material ratios) to find the optimal input parameters for each of the material ratios. Shrinkage in the x and y directions increased in correlation with the recycled ratio, compared to virgin material. Meanwhile, the tensile strength of the thick plate part continued to decrease when the recycled ratio increased. R30 (70:30) had the optimum shrinkage in the x direction with respect to R0 (100:0) material where the shrinkage increased by 24.49% (RSM) and 33.20% (PSO). On the other hand, the shrinkage in the y direction for R30 material increased by 4.48% (RSM) and decreased by 2.67% (PSO), while the tensile strength of R30 (70:30) material decreased by 0.51% (RSM) and 2.68% (PSO) as compared to R0 (100:0) material. Validation tests indicated that the optimal setting of processing parameter suggested by PSO and RSM for R0 (100:0), R30 (70:30), R40 (60:40) and R50 (50:50) was less than 10%.     

The Influence of MMA Esterification on Interfacial Adhesion and Mechanical Properties of Hybrid Kenaf Bast/Glass Fiber Reinforced Unsaturated Polyester Composites

The demand for natural fiber hybrid composites for various applications has increased, which is leading to more research being conducted on natural fiber hybrid composites due to their promising mechanical properties. However, the incompatibility of natural fiber with polymer matrix limits the performance of the natural fiber hybrid composite. In this research work, the mechanical properties and fiber-to-matrix interfacial adhesion were investigated. The efficiency of methyl methacrylate (MMA)-esterification treatments on composites’ final product performance was determined. The composite was prepared using the hand lay-up method with varying kenaf bast fiber (KBF) contents of 10, 15, 20, 25, 30, 35 (weight%) and hybridized with glass fiber (GF) at 5 and 10 (weight%). Unsaturated polyester (UPE) resin and methyl ethyl ketone peroxide (MEKP) were used as binders and catalysts, respectively. Scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR) were used to examine the effects of MMA-esterification treatment on tensile strength and morphology (tensile fracture and characterization of MMA-esterification treatment) of the composite fabricated. The tensile strength of MMA-treated reinforced UPE and hybrid composites are higher than that of untreated composites. As for MMA treatment, 90 min of treatment showed the highest weight percent gain (WPG) and tensile strength of KBF-reinforced UPE composites. It can be concluded that the esterification of MMA on the KBF can lead to better mechanical properties and adhesion between the KFB and the UPE matrix. This research provides a clear reference for developing hybrid natural fibers, thus contributing to the current field of knowledge related to GF composites, specifically in transportation diligences due to their properties of being lightweight, superior, and involving low production cost.     

An Exploratory Study on Resistance Spot Welding of Titanium Alloy Ti-6Al-4V

Resistance spot welding (RSW) is one of the most effective welding methods for titanium alloys, in particular Ti-6Al-4V. Ti-6Al-4V is one of the most used materials with its good ductility, high strength, weldability, corrosion resistance, and heat resistance. RSW and Ti-6Al-4V materials are often widely used in industrial manufacturing, particularly in automotive and aerospace industries. To understand the phenomenon of resistance spot weld quality, the physical and mechanical properties of Ti-6Al-4V spot weld are essential to be analyzed. In this study, an experiment was conducted using the Taguchi L9 method to find out the optimum level of the weld joint strength. The given optimum level sample was analyzed to study the most significant affecting RSW parameter, the failure mode, the weld nugget microstructure, and hardness values. The high heat input significantly affect the weld nugget temperature to reach and beyond the β-transus temperature. It led to an increase in the weld nugget diameter and the indentation depth. The expulsion appeared in the high heat input and decreased the weld nugget strength. It was caused by the molten material ejection in the fusion zone. The combination of high heat input and rapid air cooling at room temperature generated a martensite microstructure in the fusion zone. It increased the hardness, strength, and brittleness but decreased the ductility.     

Recent advances in syntheses,properties and applications of TiO2 nanostructures

TiO₂ is a compound of great importance due to its remarkable catalytic and distinctive semiconducting properties. It is also a chemically stable, non-toxic and biocompatible material. Nano TiO₂ is strong oxidizing agent with a large surface area and, hence, high photo-catalytic activities. With low production cost and a high dielectric constant, it is an inexpensive material. It can be prepared by diverse procedures such as solution and gas phase procedures. Nowadays, TiO₂ is being used frequently for photo degradation of organic molecules and water splitting for hydrogen generation. Most important applications include purification, disinfection of waste water, self-cleaning coatings for buildings in urban areas and the production of the green currency of energy (hydrogen) by splitting water. The review describes the advances in the syntheses, properties and applications of TiO₂ nano structures. Besides, efforts are also made to discuss the working mechanism and future challenges and perspectives.

TiO₂ is a compound of great importance due to its remarkable catalytic and distinctive semiconducting properties.