The proton-activated G protein coupled receptor OGR1 acutely regulates the activity of epithelial proton transport proteins

The Ovarian cancer G protein-coupled Receptor 1 (OGR1; GPR68) is proton-sensitive in the pH range of 6.8 - 7.8. However, its physiological function is not defined to date. OGR1 signals via inositol trisphosphate and intracellular calcium, albeit downstream events are unclear. To elucidate OGR1 function further, we transfected HEK293 cells with active OGR1 receptor or a mutant lacking 5 histidine residues (H5Phe-OGR1). An acute switch of extracellular pH from 8 to 7.1 (10 nmol/l vs 90 nmol/l protons) stimulated NHE and H(+)-ATPase activity in OGR1-transfected cells, but not in H5Phe-OGR1-transfected cells. ZnCl(2) and CuCl(2) that both inhibit OGR1 reduced the stimulatory effect. The activity was blocked by chelerythrine, whereas the ERK1/2 inhibitor PD 098059 had no inhibitory effect. OGR1 activation increased intracellular calcium in transfected HEK293 cells. We next isolated proximal tubules from kidneys of wild-type and OGR1-deficient mice and measured the effect of extracellular pH on NHE activity in vitro. Deletion of OGR1 affected the pH-dependent proton extrusion, however, in the opposite direction as expected from cell culture experiments. Upregulated expression of the pH-sensitive kinase Pyk2 in OGR1 KO mouse proximal tubule cells may compensate for the loss of OGR1. Thus, we present the first evidence that OGR1 modulates the activity of two major plasma membrane proton transport systems. OGR1 may be involved in the regulation of plasma membrane transport proteins and intra- and/or extracellular pH.     

Investigation on the surface properties of chemically modified natural fibers using inverse gas chromatography

This paper presents the application of inverse gas chromatography (IGC) technique for characterization and comparison of the surface properties of the natural fibers as reinforcement fillers in wood plastic composites. The effects of chemical modification using 1% NaOH were also studied. The fibers used for this work were Iranian cultivated eucalyptus, spruce, bagasse, and wheat straw. Chemical composition of fibers was found to be modified after treatment as characterized by Fourier transform infrared spectroscopy (FTIR). The crystallinity of fibers and the specific interaction was improved by the alkaline treatment, with more relevance to the agro-fibers. The IGC shows also a general increase in the wettability of the modified fiber when compared with the raw (unmodified) samples. Alkaline treatment achieves the best overall improvement in the properties evaluated of the agro-fibers when compared to the wood fibers.     

Safety,Health, and Environmental Risk Assessment of a Gas Power Plant: A Case Study from Southern Iran

This research was conducted to assess health, safety, and environmental risks of a gas power plant in southern Iran. In order to identify the subject risks of the power plant at operational phase a questionnaire was designed using the Delphi method. The questionnaires were put at the disposal of 99 electricity industry experts. Risk assessment was done using multicriteria decision-making methods such as technique for order of preference by similarity to ideal solution (TOPSIS), entropy, and Eigenvector technique. Following prioritization of risks at each power plant unit, top-priority risks were determined by one-way ANOVA. The obtained results indicated that the risk of working with medium voltage boards with a weight of 0.879 at the power plant's Electricity Unit is the most important safety and health risk in the studied power plant while risk of servicing the unit with fuel of gas weighting 0.807 and delivery of gas fuel with weight of 0.630 in the Exploiting Unit and work on liquid fuel clutch with weight of 0.603 in the Mechanical Unit are the most important environmental risks in the gas power plant. In conclusion, this study concludes that health, safety, and environmental risk assessment can be a structured and used as a systematic approach to plan for environmental protection and personnel health.     

Nickel oxide nanoparticles exert selective toxicity on skin mitochondria and lysosomes isolated from the mouse model of melanoma

Nickel oxide nanoparticles (NiO‐NPs) are progressively used for an immense number of new applications in modern industries sectors. Nevertheless, the toxic impact of NiO‐NPs has not been clearly elucidated on human melanoma cell lines at the cellular and molecular level. Hence, this study was designed to examine the in vitro cytotoxicity potentials of NiO‐NPs on malignant cutaneous melanoma (MCM) mitochondria. Results revealed that NiO‐NPs significantly increased reactive oxygen species level, lipid peroxidation, and mitochondrial membrane potential and decreased succinate dehydrogenase activity, glutathione level, and ATP content on skin mitochondria isolated from the mouse model of melanoma compared with the non‐cancerous mouse skin mitochondria. Our results revealed that NiO‐NPs induced lysosomal membrane labialization on mentioned mitochondria. The current study showed that NiO‐NPs could significantly induce selective cytotoxicity on MCM mitochondria. Therefore, this compound may be considered as a promising candidate for further in vivo and clinical studies to reach a new anti‐MCM drug.     

Synthesis and study of new paramagnetic and diamagnetic verapamil derivatives

New derivatives of verapamil (1) modified with nitroxides and their precursors were synthesized and screened for reactive oxygen species (ROS)-scavenging activities. The basic structure was modified by changing the nitrile group to an amide or the methyl substituent on tertiary nitrogen with nitroxides and their reduced forms (hydroxylamine and secondary amines). Among the new verapamil derivatives compound 16B [Mohan, I. K.; Kahn, M.; Wisel, S.; Selvendiran, K.; Sridhar, A.; Carnes, C.A.; Bognár, B.; Kálai, T.; Hideg, K.; Kuppusamy, P. Am. J. Physiol. Heart Circ. Physiol. 2009, 296, 140], modified with hydroxylamine salt of 2,2,6,6-tetramethyl-1,2,3,6-tetrahydropyridine-1-yloxyl proved to be the best ROS scavenger in vitro and protected HSMC and CHO cells against H₂O₂ induced damage.     

Prevalence of metabolic syndrome in Iranian professional drivers: results from a population based study of 12,138 men

Background

It is evident that professional driving is associated with substantial changes in lifestyle habits. Professional drivers are prone to metabolic syndrome (MetS) and its complications because their working environment is characterized by numerous stress factors such as lack of physical activity due to working in a fixed position, disruption in diet, and irregular sleep habits. The aim of the present study was to estimate the prevalence of MetS among long distance drivers residing in West Azerbaijan province in Iran.

Materials

To assess the prevalence of metabolic syndrome among professional long distance drivers, 12138 participants were enrolled in this cross sectional study. The MetS was defined using International Diabetes Federation criteria.

Results

Among12138 participants, 3697 subjects found to be MetS. The crude and age-adjusted rates of MetS were 30.5% and 32.4% respectively. Based on Body mass index (BMI), 5027 subjects (41.4%) were overweight (BMI ≥25.01–30 kg/m2), and 2592 (21.3%) were obese (BMI ≥30.01 kg/m2). The presence of central obesity was more common than other components. The associations of MetS with BMI, pack-year smoking, age, weekly driving duration and driving experiences were significant in the logistic regression. By increasing BMI, pack-year smoking, age, weekly driving duration and driving experiences, odds ratio of MetS was increased.

Conclusion

The study suggests that MetS has become a noteworthy health problem among Iranian long distance drivers. This might be due to the following facts: sitting in a fixed position for long hours while working, cigarette smoking, job stress, unhealthy diet and lack of physical activity. Educational programs should be established for promoting healthy lifestyle and also for early detection and appropriate interventions     

CD4 T Cell Help Is Limiting and Selective during the Primary B Cell Response to Influenza Virus Infection

Influenza virus vaccination strategies are focused upon the elicitation of protective antibody responses through administration of viral protein through either inactivated virions or live attenuated virus. Often overlooked in this strategy is the CD4 T cell response: how it develops into memory, and how it may support future primary B cell responses to heterologous infection. Through the utilization of a peptide-priming regimen, this study describes a strategy for developing CD4 T cell memory with the capacity to robustly expand in the lung-draining lymph node after live influenza virus infection. Not only were frequencies of antigen-specific CD4 T cells enhanced, but these cells also supported an accelerated primary B cell response to influenza virus-derived protein, evidenced by high anti-nucleoprotein (NP) serum antibody titers early, while there is still active viral replication ongoing in the lung. NP-specific antibody-secreting cells and heightened frequencies of germinal center B cells and follicular T helper cells were also readily detectable in the draining lymph node. Surprisingly, a boosted memory CD4 T cell response was not sufficient to provide intermolecular help for antibody responses. Our study demonstrates that CD4 T cell help is selective and limiting to the primary antibody response to influenza virus infection and that preemptive priming of CD4 T cell help can promote effective and rapid conversion of naive B cells to mature antibody-secreting cells.     

Sleep habits of Iranian pre-school children in an urban area: Late sleeping and sleep debt in children

Using BEARS (Bedtime problems, Excessive sleepiness, Awakenings during the night, Regularity of sleep, Snoring), and CSHQ (Children’s Sleep Habits Questionnaires) screening tools with 224 participants revealed that Iranian children have shorter night sleep duration than expected (9.54 vs 12 h) for their age group. Earlier sleepers had longer night sleep duration (10:36 ± 1:12; 9:12 ± 1:06 h, P > 0.001), and total daily sleep time (11:36 ± 1:42; 10:36 ± 1:30 h, P = 0.005) than late sleepers. A majority (85%) of naptakers had sleep bedtime of 22:00 or later. The poor sleep quality of Iranian preschool children is probably due to cultural characteristics, climate differences, or harmful sleep habits.

     

Solidification/Stabilization of Cresol-Contaminated Soil: Mechanical and Leaching Behavior

In this research, the effects of a solidification/stabilization (S/S) technique on the remediation of cresol-contaminated soil were investigated. The soil samples were collected from the Tehran Oil Refinery (TOR) in Ray District, Iran. Cresols are hazardous chemicals whose exposure at high dosage results in irreparable damage to animal and human health. S/S process progresses through physicochemical reactions, reducing the leachability of a waste as well as changing its physical properties in order to encapsulate the contaminants and form a solid material. The samples were spiked by certain concentrations of cresols including meta-, ortho-, and para-isomers. The treatment process was conducted using Portland cement as the binder and modified bentonite as a stabilizer. The efficiency of the S/S technique was assessed by the unconfined compressive strength (UCS) test and toxicity characteristic leaching procedure (TCLP) test. The results of the tests showed that adding 20% and 30% Portland cement in combination with 15% and 30% modified bentonite to contaminated samples increased the 28-day compressive strength of S/S blocks to a range of 2.44 to 3.08 MPa. In fact, increasing the proportion of cement in the mix design resulted in enhanced compressive strength, while modified bentonite inversely affected samples’ strength. Regarding leaching behavior, adding organophilic clay to polluted samples noticeably declined cresol's concentrations in leachate. Overall efficiency of S/S in terms of leaching was about 70%, which was obtained by adding 20% cement and 30% modified clay. A logarithmic relationship between leaching percent and modified clay ratio was also detected with high logarithmic and linear correlation coefficients of 0.96 and 0.9, respectively, hence presenting the efficiency of S/S in stabilizing the cresols in the samples.