Concurrent assessment of personal, indoor, and outdoor PM2.5 and PM1 levels and source contributions using novel low-cost sensing devices.

The intensity, frequency, duration, and contribution of distinct PM2.5 sources in Asian households have seldom been assessed; these are evaluated in this work with concurrent personal, indoor, and outdoor PM2.5 and PM1 monitoring using novel low-cost sensing (LCS) devices, AS-LUNG. GRIMM-comparable observations were acquired by the corrected AS-LUNG readings, with R2 up to 0.998. Twenty-six non-smoking healthy adults were recruited in Taiwan in 2018 for 7-day personal, home indoor, and home outdoor PM monitoring. The results showed 5-min PM2.5 and PM1 exposures of 11.2 ± 10.9 and 10.5 ± 9.8 µg/m3 , respectively. Cooking occurred most frequently; cooking with and without solid fuel contributed to high PM2.5 increments of 76.5 and 183.8 µg/m3 (1 min), respectively. Incense burning had the highest mean PM2.5 indoor/outdoor (1.44 ± 1.44) ratios at home and on average the highest 5-min PM2.5 increments (15.0 µg/m3 ) to indoor levels, among all single sources. Certain events accounted for 14.0%-39.6% of subjects' daily exposures. With the high resolution of AS-LUNG data and detailed time-activity diaries, the impacts of sources and ventilations were assessed in detail.

The relationship between mental health and undergraduate student achievement:A study at Universiti Utara Malaysia / Jurnal Sains Kesihatan Malaysia

Mental health is an integral component to the formation of human capital performance. Human capital with high productivity is the key factor to the growth of a country. Thus, this study aims to investigate the relationship between the level of mental health of undergraduate students in Universiti Utara Malaysia (UUM) with their performance. Mental health was measured using the General Health Questionnaire 12-item (GHQ-12) and the performance was based on the Cumulative Grade Point Average (CGPA). A total of 316 undergraduate students at UUM had answered questionnaires that were distributed. The data were analysed descriptively and the effect of the level of mental health on performance was tested using probit model. Based on GHQ-12, 48% respondents were found to have a good mental health status. A total of 67.21% of the students who obtain CGPA 3.67 and above have a good level of health compared with only 36.08% for those with CGPA under 3.67. Based on the probit model, the level of mental health was found to be significant at 1% level in influencing the CGPA. These findings provide indication to policy makers of the importance of mental health in influencing the students’ performance. Mental health education programs should be implemented or enhanced to raise awareness of the importance of good mental health state among students in higher education institution.

Hypochlorous acid induces apoptosis of cultured cortical neurons through activation of calpains and rupture of lysosomes.

3-Chlorotyrosine, a bio-marker of hypochlorous acid (HOCl) in vivo, was reported to be substantially elevated in the Alzheimer's disease (AD) brains. Thus, HOCl might be implicated in the development of AD. However, its effect and mechanism on neuronal cell death have not been investigated. Here, we report for the first time that HOCl treatment induces an apoptotic-necrotic continuum of concentration-dependent cell death in cultured cortical neurons. Neurotoxicity caused by an intermediate concentration of HOCl (250 microm) exhibited several biochemical markers of apoptosis in the absence of caspase activation. However, the involvement of calpains was demonstrated by data showing that calpain inhibitors protect cortical neurons from apoptosis and the formation of 145/150 kDa alpha-fodrin fragments. Moreover, an increase in cytosolic Ca2+ concentration was associated with HOCl neurotoxicity and Ca2+ channel antagonists, and Ca2+ chelators prevented cleavage of alpha-fodrin and the induction of apoptosis. Finally, we found that calpain activation ruptured lysosomes. Stabilization of lysosomes by calpain inhibitors or imidazoline drugs, as well as inhibition of cathepsin protease activities, rescued cells from HOCl-induced neurotoxicity. Our results showed for the first time that HOCl induces apoptosis in cortical neurons, and that the cell death process involves calpain activation and rupture of lysosomes.

Adenosine induced apoptosis in BHK cells via P1 receptors and equilibrative nucleoside transporters.

Adenosine, as a ubiquitous metabolite, mediates many physiological functions via activation of plasma membrane receptors. Mechanisms of most of its physiological roles have been studied extensively, but research on adenosine-induced apoptosis (AIA) has only started recently. In this study we demonstrate that adenosine dose-dependently triggered apoptosis of cultured baby hamster kidney (BHK) cells. Adenosine-induced apoptotic cell death was characterized by DNA laddering, changes in nuclear chromatin morphology and phosphatidylserine staining. Apoptosis was also quantified by flow cytometry. Results suggest the involvement of adenosine A1 and A3 receptors as well as equilibrative nucleoside transporters in apoptosis induced by adenosine. These results indicate a receptor-transporter co-signaling mechanism in AIA in BHK cells. The involvement of A1 and A3 receptors also implies a possible apoptotic pathway mediated by G protein-coupled receptors.

Anti-diabetic activity of the semi-purified fractions of Averrhoa bilimbi in high fat diet fed-streptozotocin-induced diabetic rats.

The present study was designed to investigate the hypoglycemic and hypolipidemic activities of the semi-purified fractions of an ethanolic leaf extract of Averrhoa bilimbi (ABe) in high fat diet (HFD)-streptozotocin (STZ)-induced diabetic rats. Male Sprague-Dawley rats aged 10 weeks (200-250 g) were fed with a high fat diet obtained from Glen Forrest stock feeders (Western Australia) for 2 weeks prior to intraperitoneal injection with streptozotocin (STZ, 50 mg/kg). The leaves of A.bilimbi were exhaustively extracted with 80% ethanol, concentrated at 40 degrees C using a rotavapor and partitioned successively with butanol, ethylacetate and hexane to get aqueous (AF), butanol (BuF), ethylacetate (EF), and hexane fractions (HF). The fractions were freeze-dried to obtain powders of each. To investigate the effect of long term administration of the hypoglycemic fractions, diabetic animals were treated with vehicle (distilled water), AF (125 mg/kg), or BuF (125 mg/kg), twice a day for 14 days. The long term administration of AF and BuF at a dose of 125 mg/kg significantly (P < 0.05) lowered blood glucose and triglyceride concentrations when compared to the vehicle. The hepatic glycogen content was significantly higher (P < 0.05) in AF-treated rats when compared to diabetic control, however no change was found in the BuF-treated rats. Moreover, AF as well as BuF did not cause any significant change in the total cholesterol and HDL-cholesterol. There was also no difference in liver thiobarbituric acid reactive substances (TBARS) and cytochrome P450 values between AF, BuF and vehicle-treated control rats. In conclusion, the results indicate that AF is more potent than BuF in the amelioration of hyperglycemia and hyperlipidemia in HFD fed-STZ diabetic rats. Hence, AF is a potential source for the isolation of active principle(s) for oral anti-diabetic therapy.