Hormesis can be defined as a biphasic dose-response relationship characterized by low-dose simulation and high-dose inhibition. Given that environmental pollutants are more often found at lower doses, hormesis research has become a recent hot spot in toxicology. This study summarizes current progress on hormesis research, which can be discussed in three contexts: The universality of hormesis, hormesis mechanisms, and the quantification of hormetic responses. The universality of hormesis has been verified, but the degree to which hormesis should be taken into risk assessments and risk management plans remains controversial. Regarding mechanisms, we discuss how our mechanistic understanding of hormesis has come a long way but still lacks strong experimental support, which leads to uncertainty as to the exact underlying causes of hormesis. This study also describes the hormesis quantitative research process and points out that due to an incomplete mechanistic understanding of hormesis, quantitative research has progressed slowly and lacks accurate quantitative characterization parameters and prediction models. Finally, we discuss that a future trend may be to investigate hormesis quantitative characterization parameters based on toxicity mechanism and to establish a quantitative prediction model of hormesis that incorporates those parameters.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

Ambient air pollution is composed of a heterogeneous mixture of gaseous and solid particle compounds in which primary particles are emitted directly into the atmosphere, such as diesel soot, while secondary particles are created through physicochemical transformation. Particulate matter (PM), especially fine and ultrafine particles, can be inhaled and deposited in the alveolar cavities and penetrate into circulation. An association between high levels of air pollutants and human disease has been known for more than half a century and increasing evidence demonstrates a strong link between exposure on PM and the development of systemic diseases such as cardiovascular and neurological disorders. Experimental animal models have been extensively used to study the underlying mechanism caused by environmental exposure to ambient PM. Due to their availability, quality, cost, and genetically modified strains, rodent models have been widely used. Some common exposure approaches include intranasal instillation, intratracheal instillation, nose-only inhalation, whole-body inhalation, and intravenous injection have been reviewed with a brief summary of its performance, merit, limitation, and application. We hope this would provide a useful reference in advancing experimental researches about air pollution human health and disease development.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

Particulate matter (PM) air pollution is a leading public health concern across most of the populated world. Elevated PM levels cause both acute increases in cardiovascular mortality and the development of long-term neurological pathology. Upon inhalation, PM reaches the brain through entry into pulmonary capillaries and directly through the olfactory mucosa. Population-based and animal studies reveal decreases in brain size and increases in inflammatory markers following long-term exposure to elevated PM concentrations. In vitro, cell culture studies indicate that components of PM air pollution are neurotoxic. In addition to direct effects on the central nervous system (CNS), PM induces aberrant local and systemic inflammatory responses that can induce and exacerbate cerebral injury. Hypertension and decreased cerebral blood flow velocity are observed within days of increased PM exposure and may contribute to short-term rises in mortality rate. Substantial epidemiological evidence links PM concentration with both short-term and long-term risk of stroke. It has been suggested that the increased stroke risk is due to potentiation of cerebrovascular inflammation, endothelial cell dysfunction, reactive oxygen species production, and atherosclerosis. This review examines the pathophysiological mechanisms by which PM damages the CNS and the cerebrovasculature.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

Over the past 30 years, particulate matter (PM) air pollution has progressively worsened in many of China's urban and suburban areas. This review provides a current picture of the air pollution in China with an emphasis on the history of PM pollution, policies and reduction goals, recent improvements, and known adverse health effects of PM exposure. Several studies have provided the analyses of current PM pollution levels in cities across China using satellite data and air-monitoring stations. These analyses are consistent with the Chinese Ministry of Environmental Protection (MEP) 2015 air pollution report, which concluded that only 8 of 74 (10.8%) cities met the Chinese standards for safe annual average PM _2.5 exposure (35 μg/m ³ ). Even fewer cities met the World Health Organization PM _2.5 guideline of 10 μg/m ³ . The Government of China has acknowledged the public health threat of PM pollution and enacted higher standards and goals through the 12 ^th five-year plan (FYP) (2010), National Ambient Air Quality Standard (2012), the Air Pollution Prevention and Control Action Plan (2013), and the 13 ^th FYP (2016). A comparative analysis between 2010 and 2015 satellite data shows that PM pollution decreased by around 17% during this period. This improvement is corroborated by the MEP's report on the State of the Environment in 2014 and the global burden of disease report in 2013. Despite these changes, PM pollution remains a substantial public health challenge. In 2010, an estimated 1.235 million deaths in China were attributed to PM air pollution. Long-term exposure to PM pollution increases the rates of cardiovascular, metabolic, and respiratory mortality. In particular, PM exposure increases the morbidity of respiratory illnesses such as chronic obstructive pulmonary disease (COPD), asthma, and lower respiratory infections (LRIs). Elevated levels of PM have been found to increase the incidence of all of the top five causes of death in 2012: Ischemic heart disease, stroke, COPD, LRI, and lung cancer. In addition, higher PM pollution decreases average birth weight, raises incidence of preterm birth, and increases the prevalence of Type II diabetes mellitus across the population. With the knowledge of these serious health consequences, China must enact greater measures to reduce dangerous PM levels.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

Introduction: Clinical history and examination are very important for determining allergy. The most common forms being bronchial asthma (BA) and allergic rhinitis (AR). A lot of patients respond to the primary line of treatment. Patients come forward with the objective of uprooting the cause of these allergies. Skin prick test (SPT) helps in finding the most likely cause after which we can offer them the desensitization and protective advice. Objective: To evaluate the performance of various aeroallergens by assessment with SPT in Central India population. Materials and Methods: One hundred and forty-three patients with BA and AR were subjected to SPT. SPT was performed with antigen extracts from India. Results: Of the 143 patients, 86 (60%) patients had both BA and AR. These 143 patients showed 454 positive SPT results. Of the 454, 223 (49%) were positive for mites alone. Among the three mites tested for, Dermatophagoides pteronyssinus 81 (17.8%) was the most common. The study of seasonal distribution of allergens showed peaked results for mites in winter. Parthenium hysterophorus (congress grass) 11 (7.7%) was the most common pollen found. Conclusions: The dust mite had the greatest frequency in this study. Humidity levels are critical for the growth of mites, which provides a valuable clue to protect against it. Avoiding the relevant allergens can be a remedy for AR patients and reduce the frequency of symptoms in asthmatics.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

Peptic ulcer (PU) is the most common disease of gastrointestinal tract (GIT) which affects the stomach and duodenum. It is characterized by an imbalance between the aggressive and defensive factors. Lifestyle and eating habits play an important role in the case of PU. According to the latest World Health Organization data published in April 2011, PU disease deaths in India reached 108,392 or 1.20% of the total deaths. The age-adjusted death rate is 12.37/100,000 of population, which leads India to 5^th rank in the world. The aim of this review was to summarize the scientific data, herbal research, nutritional therapy, precautions, and pharmacological/nonpharmacological treatment regarding PU. The update conclusion regarding PU therapy was concluded with the help of published scientific data on Pub Med, Google Scholar, Med Know, Elsevier and other online resources. Natural remedies are found to be safe (minimum side effects) whereas, in allopathic treatment, antacids with the combination of proton pump inhibitors can better control PU. A balanced dietary plan should be advised by health care professionals or providers to patients suffering from PU. Following good habits and avoiding spicy food make our GIT healthy. Hence, a better lifestyle automatically cures the PU. Better knowledge with balanced lifestyle is an excellent treatment of PU.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

Background: Secondhand smoke (SHS) exposure is linked with neurobehavioral disorders in children. This study evaluated the SHS exposure and autism spectrum disorders (ASD) in children in the United States. Materials and Methods: Parent-reported postnatal SHS exposure and ASD diagnosis were examined in children age 2 to 12 years using the 2011–2012 National Survey on Children's Health. The physician diagnosis of current ASD as reported by the parents was used as the outcome. Logistic regression analysis was used to evaluate the association of ASD with SHS after adjusting for risk factors. Results: Of the 56,710 children, 24% had SHS exposure, 2% had ASD, and the mean age was 7 years. SHS exposure was associated with 47% greater odds of ASD in male children (adjusted odds ratio [OR] = 1.47; 95% confidence interval [CI] =1.05, 2.07; P = 0.025). In contrast, SHS was not significantly associated with ASD in female children (adjusted OR = 0.72; 95% CI = 0.40, 1.29; P = 0.266). Other significant factors associated with ASD diagnosis in male children were age, income, mother's education, and mental health status. Conclusions: SHS is significantly associated with ASD in male children. Sociodemographic factors, natal and prenatal characteristics are important etiologic influences for ASD. Targeted efforts to change the smoking behavior of parents and caregivers of children could reduce ASD.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

Background: Snakebite envenoming is a neglected tropical disease that accounts for preventable morbidity and mortality, especially in resource-limited settings.  This review aimed at examining the snake and human behaviors that facilitate snake-human encounters and highlighting the primary preventive measures for snakebite and the resultant envenoming. Materials and Methods: Google Scholar, Medline (via PubMed), and African Journal Online were searched from January 1959 to April 2019 for peer-reviewed studies addressing primary prevention of snakebite. We extended our search to grey literature from conference proceedings, documents from organizations, book chapters, and thesis. Results: We found few studies in medical literature on community knowledge of the intrinsic characteristics of snakes (e.g., its unique venom apparatus for nutrition, defense and competition, and its habitat and activities); however, there is appreciable amount of studies on human activities associated with snakebite envenoming. Deservedly, more studies appear to focus on snakebite management (secondary and tertiary prevention) with inadequate emphasis on primary prevention of snakebite (which may be the only intervention in some resource-limited settings). Conclusion: Synergy of efforts toward improving community knowledge of human behaviors associated with snakebite and snake behaviors may generate appropriate environmental and behavioral responses to curtail human-snake encounters. Hence, intensive promotion of primary prevention may be a useful approach toward reducing snakebite burden in resource-limited settings.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

Hepatic diseases are a major problem of worldwide proportions, and liver damage is very common since the liver has to encounter several toxic substances during their metabolism. Pollution is also one of the major causes of hepatic dysfunctioning, high level of pollutant in blood enhances the risk for abnormal liver enzyme level. Increased industrialization has prone workers to confront the several harmful chemicals in their day-to-day life that affect liver adversely; several studies have been published in the evidence of this fact; people cannot avoid their exposure to such environmental conditions but can counter with its harmful effects. Thus, to overcome this loophole, there is a demand of such agents that has the capability to fight against such toxins and pollutants. Ursolic acid (UA), a natural pentacyclic triterpenoid carboxylic acid, has established its identity as a very potent hepatoprotective agent in recent years. It is one of the strongest natural healers that are present in several medicinal plants. Its antioxidant effect makes it a potent antihepatotoxic agent as it modulates mitogen-activated protein kinases and nuclear factor-kappa B signaling pathway. UA has anticholestatic property that enhances its effectiveness somewhere equal to or in some cases better than silymarin (a well-known potent hepatoprotective agent). In recent years, it has attracted considerable attention due to its double-edged sword effect on the liver, defined in terms of prevention and cures both.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

Gulf War illness (GWI) research has generated an abundance of interesting but diverse data. While increased molecular mechanisms have been identified, the high levels of heterogeneity for initial trigger factors, cellular defects, and symptoms continuously challenge the efforts of clinical implications of the research, including the search for biomarkers and the common mechanism of GWI. In this analysis, I consider GWI as an adaptive illness condition where system stresses and genome instability-mediated cellular evolution play an important role. By further defining GWI as an environmental illness caused by extremely high levels of specific Gulf War (GW) stresses, the challenges for GWI research are briefly reviewed, with comparisons to other common and complex diseases such as cancer. Based on the new discovery that many GWI patients display elevated genome instability coupled with increased cellular stress, a general model of GWI is proposed to unify GW-specific stress, cellular damage, and genome-heterogeneity-mediated cellular adaptation and evolution, as well as diverse-related symptoms. Finally, some new strategies are suggested based on the general model of GWI.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

Cardiovascular diseases refer to all disorders related to the heart and its circulatory system, such as atherosclerosis, arrhythmia, hypertension, and stroke. In recent years, numerous environmental studies in humans and animal models have confirmed a positive association between ambient particulate matter (PM) exposure and cardiovascular morbidity/mortality. The deleterious impacts of the exposure are involved in multiple mechanisms, in which one is due to the pro-inflammatory effects that result from the peroxidation of lipids, which provide critical structure and function in cellular membranes, the main sites of pollutant attack. This review aims to assess the current scientific literature relating to pertinent mechanisms, molecular pathways, and at-risk populations associated with cardiovascular complications induced by ambient PM exposure.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

Objective: The current study is a report of isolation and identification of Mycobacterium setense from a tap running water in a general surgery ward in a hospital in Isfahan, Iran. Materials and Methods: This bacterium was obtained from a hospital water sample according to the cetylpyridinium chloride 0.005% method on Lowenstein–Jensen slant and characterized to the species level as M. setense using results of phenotypic test and 16S rRNA sequencing. Results: This isolate identified to the species level using the conventional and molecular method as M. setense, this bacterium has highest similarity (100%) with those of M. setense CIP109395 16S rRNA gene sequences. Conclusion: This study can be useful and provide important information for learning about the natural habitats of pathogenic species of nontuberculosis mycobacteria. Furthermore, the molecular tests such as 16S rRNA gene sequencing can be applied for reliable and appropriate identification of mycobacterial species.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

[FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

[FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

Objective: The objective of this study is to investigate the antiviral activity of the Cucumis metuliferus alkaloids against Newcastle disease virus-LaSota (NDV-L). Methods: Hemagglutination (HA) test method using embryonated eggs for study. Results: The result showed "nonlethality" of the alkaloids in 10 days old embryonated eggs. Exposure of the alkaloids to NDV-L infected embryonated eggs showed negative HA test result from varying 2-fold diluted concentration between 50 and 3.125 mg/ml of the alkaloid, while the concentration between 1.563 and 0.195 mg/ml gave positive HA test. Negative HA response means the alkaloids at that concentration have antiviral activities while positive HA test implies the presence of antibodies production in response to an antigen as seen with the control, meaning that viral replication was not inhibited when the embryonated eggs were exposed to lower doses of the alkaloids. Conclusion: The study showed that the alkaloids of C. metuliferus fruit pulp extract have good margin of safety with a high level of antiviral properties as confirmed by the result of the HA test.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

Purpose: Consumption of monosodium glutamate (MSG) in food, drink, and other consumables has been linked to different observable changes believed to be as a result of MSG's effects on the brain. Furthermore, it is believed that blood–brain barrier plays a role on how these effects are felt in different stages of life. The present study is an attempt to understand the differential effect of MSG by studying body and brain weights as well as physiological changes in the behavior of rats exposed at different stages of life (either as neonate or as adult). Materials and Methods: Pups were administered 4 mg/g MSG on postnatal days 2, 4, 6, 8, and 10, allowed to mature for 26 weeks, and afterward divided into three groups (n = 6) and administered saline, 5 mg/g, and 10 mg/g MSG for 6 weeks. Two other groups, not exposed to MSG at neonatal age (adult), were similarly administered 5 mg/g and 10 mg/g MSG for 6 weeks. During this period, weight gain and behavioral observation was made, and at the end of the 6 weeks, brain weight was measured. Results: A dose-dependent effect of MSG was recorded in both neonatal- and adult-administered rats in all the parameters studied. Conclusion: MSG affects both neonate and adult rats similarly, thus adult exposure may be used in studies involving MSG and other neurotoxic chemicals.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

Neurodegenerative diseases, such as dementia, Parkinson's disease, and parkinsonism, are due to the gradual and progressive loss of neural cells, leading to nervous system dysfunction. Increasing epidemiological and toxicological evidence has demonstrated the possible association between neurological diseases and particulate air pollution. Chronic exposure to particulate matter (PM) of <2.5 μm in aerodynamic size (PM_2.5) is related to reductions in white matter and gray matter in brains of older women. Alterations of the structural integrity of the brain were reported for particulate air pollution-induced neurological disorders. Clinically, intraneuronal accumulation of tau proteins is considered to be an important hallmark of the development of neurodegenerative diseases. In Alzheimer's disease brains, for example, hyperphosphorylated levels of tau are around 3–4 times higher than levels in normal adult brains. Tau overexpression in neuroblastoma cells can lead to tau aggregations and the appearance of smaller proteolytic fragments. Degradative mechanisms, such as autophagy that remove tau from cells are considered essential functions for maintaining the brain's health. Notably, increasing numbers of reports have indicated that autophagy dysfunction occurs due to particulate air pollution in vitro and in vivo. Dysfunction of autophagy can lead to tau accumulation in the brain. We reviewed the effects of particulate air pollution on neurological diseases and the underlying mechanisms (i.e., tau and autophagy). Further toxicological evidence is required to fill in the gaps between epidemiological and clinical observations.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

[FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

Background: Bacterial resistance to antibiotics has led to a search for new antimicrobial agents. Infectious diseases caused by bacteria, fungi and viruses are a major threat to human health. Materials and Methods: Sixty marine soil samples were collected from different coastal zones and different sampling sites in Kerala and kept for anaerobic enrichment. Enrichment culture was screened for antibacterial activity by crowded plate method. From the sixty marine samples, twenty bacterial strains were isolated. Among the twenty bacterial strains, KS302 showed antimicrobial activity. Further analysis was established in aqueous and organic solvents of the crude extract. These secondary metabolites were studied for antimicrobial activity against clinical isolates of S.aureus (NCIM-5345), B. Subtilis (NCIM-2920), and E. coli (NCIM-5346). Results: Antimicrobial compound producing microorganisms were identified by anaerobic crowded plate method and purified by streak plate method. Methanolic extract as well as lipid layer did not show any antimicrobial activity but solvent layer as well as aqueous layer had shown good antimicrobial activity against all the test organisms like S.aureus (NCIM-5345), B. Subtilis (NCIM-2920), and E. coli (NCIM-5346). Conclusion: Marine anaerobic microorganisms can be explored by isolating a novel compound, which can be used as the drug of choice against pathogenic bacteria.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

Background: Medicinal plants present a wide range of potentially phytochemical compounds that contain many useful properties including anticancer, enzyme inhibition, anti-inflammatory, antifungal, antibacterial, immunomodulatory, antioxidant, and antiallergic activities. Phyllanthus niruri capsules are extensively recommended to improve the function of the diseased liver. Its leaves root and the whole plant are used as an herbal complement. Aim: The present study was aimed to focus on the in vitro immunomodulatory activity, antifungal, antibacterial and phytochemical screening of aqueous, methanolic, and ethanolic extract of P. niruri. Materials and Methods: Immunomodulatory activities were evaluated through nitroblue tetrazolium assay. Antifungal and antibacterial activity were conducted against Candida albicans (NCIM - 3100), Aspergillus niger (NCIM - 1028), Eschericha coli (NCIM - 5346), Bacillus subtilis (NCIM - 2920), and Staphylococcus aureus (NCIM - 5345) by using disc diffusion method. Results: Medicinal plants contain polyphenolic compounds which have potent anti-cancer and immunomodulator activity. P. niruri has potential immunomodulatory activity. Aqueous, methanolic, and ethanolic extract of P. niruri did not show any significant antifungal activity and 100 mg/ml, 150 mg/ml, and 200 mg/ml. Aqueous, methanolic, and ethanolic extract showed significant antibacterial activity. Conclusion: From this study, it is concluded that P. niruri does not have antifungal activity but has potent immunomodulatory and antibacterial activity. This immunomodulatory and antibacterial activity of P. niruri may be due to the secondary metabolites such as alkaloid, tannins, terpenoids, flavonoids, and phenol compounds.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

Study Background: Toxocara canis is a helminths parasite known as dog worm but infects human through infected dog feces or contaminated dirt. It is a neglected disease in economically less privileged areas. The parasitic infection can generate inflammatory process. Aim and Objective: This work was designed to determine the seroprevalence of T. canis and the parasitic effect on plasma cytokines in children aged 6–11 years in Saki-East local government area in Nigeria. Materials and Methods: Two hundred children aged 6–11 years (female – 100 and male – 100) were recruited across Saki-East local government area. One hundred and sixty-one of them not infected with any of the infectious agents were studied as control. Sputum, blood, stool, skin snip, and urine samples were obtained for microscopic identification of parasites. Sputum sample was also used for Ziehl–Neelsen staining to demonstrate acid-fast bacilli, while ELISA technique was used for determination of T. canis, anti-hepatitis C virus (HCV), HBsAg, HIV1-p24 antigen, tumor necrosis factor-alpha (TNFα), and interleukin (IL)-10. Results: The results obtained showed overall seroprevalence of T. canis among the children as 9.5% (19) including 6% (12) male and 3.5% (7) female children. This included 5.5% (11) monoinfected with T. canis; 1% (2) were T. canis coinfected with Ascaris lumbricoides; 1% (2) were T. canis coinfected with hepatitis B virus; 1% (2) were T. canis coinfected with Plasmodium spp.; 0.5% (1) were T. canis coinfected with hookworm; and 0.5% (1) were T. canis coinfected with Schistosoma haematobium. There is no coinfection with either HIV or HCV among the children. 10% (20) were infected with infectious agents but seronegative to T. canis. There was a significant increase in the plasma values of cytokines TNFα and IL-10 in T. canis monoinfected children compared with the control (P < 0.05). Conclusion: The work revealed an overall seroprevalence of T. canis as 9.5% including 5.5% monoinfection and a significant increase in plasma TNFα and IL-10 in T. canis monoinfection.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

Aim: This study aimed to establish liquid–liquid extraction (LLE) for estimation of hippuric acid (HA) in urine as a biomarker of the toluene exposure by high-performance liquid chromatography equipped with photodiode array detector (HPLC-PDAD). Method: HA in urine was extracted by LLE and determined by HPLC-PDAD. The operating conditions with HPLC were ODS-2 hypersil column (250 mm × 4.6 mm, 5 μm), 0.1% trifluoro acetic acid (TFA) in acetonitrile and 0.1% TFA in water as mobile phase, 1 ml/min flow rate, and wavelength of 205 nm. The validity of the present method was tested by the estimation of HA in urine samples, collected from toluene-exposed (shoe workers) and unexposed or control subjects. Results: Binary gradient system was used to achieve optimum separation. The analytical curve prepared for HA in aqueous solution in the range of 0.5–10 μg/ml showed determination coefficient value (R²) 0.998. Limit of detection and quantification (LOQ) were 0.46 and 1.53 μg/ml, respectively. The coefficients of variance for intraday precision were 1.4% for HA standard (5 μg/ml) and 1.1% for pooled urine, whereas inter-day precision values were 3.2% and 4.9% for HA standard and pooled urine, respectively. Method recovery obtained was 96%–120% for HA solutions containing 2, 3, and 5 μg/ml, demonstrating that precision and recovery of method were satisfactory. Compared to unexposed group, exposed group had significantly more HA. It was found significantly (P < 0.05) higher in urine of exposed workers (32.52 ± 10.91) than unexposed group (16.21 ± 10.14). Conclusion: Sample preparation by LLE is simple and cost-effective for the determination of HA as a biomarker of toluene exposure by HPLC-PDAD. It can be used to detect HA in urine for population exposed to toluene.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

Background: Air pollution is one of the greatest public health concerns worldwide. In order to understand its mechanism of harm, we investigated the effects of diesel exhaust particles (DEPs), one of the major constituents of ambient air pollutants, on reactive cell viability, oxygen stress, autophagy, and apoptosis. Materials and Methods: In in vitro human umbilical vein endothelial cell (HUVEC) model, cells were exposed to freshly dispersed DEP preparations at 0, 12.5, 25, 50, 100, or 200 µg/mL for 24 h or at 50 µg/mL DEP for 1, 3, 6, 12, or 24 h. Cell survival and oxidative stress were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, activity of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX), and generation of reactive oxygen species (ROS). Protein expressions of autophagy (Beclin-1, p62, and light chain 3 [LC3]-II) and apoptosis (Bcl2 and Bax) were assayed by Western blotting. Results: DEP induced a significant dose-dependent and temporal decrease in cell viability and increase in ROS generation and NOX activity, in association with decreased or increased protein levels of p62 or Beclin-1, as well as conversion of the LC3 in a dose-dependent manner. DEP increased pro-apoptotic protein Bax and decreased anti-apoptotic protein Bcl2. Conclusions: These results demonstrated that DEP exposure induced cytotoxicity, oxidative stress, autophagy, and apoptosis in HUVECs. Novel insight into the mechanisms of cardiovascular diseases caused by air pollution may be provided through these findings.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

Background: Preliminary evidence suggests that environmental factors may modify the transmission of SARS-CoV-2 infection. Although the role of non-pharmaceutical interventions (NPIs) on the reduction of SARS-CoV-2 transmission rate is well explored, the role of local climate across different geographical transects on the onset and transmission of SARS-CoV-two remains unclear. Aims and Objectives: In this study, we explored the potential association among climatic factors, non-climatic factors and COVID-19 burden, via Pearson correlation analysis. We also investigated the association between COVID-19 cases and cumulative effect of NPIs or behavioral changes during lockdown as non-climatic factors in our analysis. Setting and Design: The research was carried out in the COVID-19 impacted districts across Nepal. Material and Methods: The meteorological/climatic factors consisting of temperature and rainfall as predictor variables and total laboratory confirmed COVID-19 cases reported between January and May 2020 were considered in the study. Statistical Analysis Used: The statistical tests were carried out using R programming language. Results: Of the total 375 confirmed positive cases until May 19, 2020, clusters of the cases were diagnosed from the Terai region, which was associated with comparatively higher temperature and open border to India. Upon time series and spatial analysis, the number of positive cases increased after the end of April, possibly due to expansion of diagnostic tests throughout the country. We found a positive correlation betweenCOVID-19, and temperature indices (mean and minimum) (P < 0.05). Conclusions: In the absence of an effective vaccine, these findings can inform infection control division of Nepal on the implementation of effective NPIs based on the observed variability in meteorological factors, especially in prevention of possible second wave of infection during winter.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

Background: Chemical intolerance (CI) is characterized by multisystem symptoms initiated by a one-time high-dose or a persistent low-dose exposure to environmental toxicants. Prior studies have investigated symptom clusters rather than defined comorbid disease clusters. We use a latent class modeling approach to determine the number and type of comorbid disease clusters associated with CI. Methods: Two hundred respondents with and without CI were recruited to complete the Quick Environmental Exposure and Sensitivity Inventory (QEESI), and a 17-item comorbid disease checklist. A logistic regression model was used to predict the odds of comorbid disease conditions between groups. A latent class analysis was used to inspect the pattern of dichotomous item responses from the 17 comorbid diseases. Results: Those with the highest QEESI scores had significantly greater probability of each comorbid disease compared to the lowest scoring individuals (P < 0.0001). Three latent class disease clusters were found. Class 1 (17% of the sample) was characterized by a cluster consisting of irritable bowel syndrome (IBS), arthritis, depression, anxiety, fibromyalgia, and chronic fatigue. The second class (53% of the sample) was characterized by a low probability of any of the co-morbid diseases. The third class (30% of the sample) was characterized only by allergy. Discussion: We have demonstrated that several salient comorbid diseases form a unique statistical cluster among a subset of individuals with CI. Understanding these disease clusters may help physicians and other health care workers to gain a better understanding of individuals with CI. As such, assessing their patients for CI may help identify the salient initiators and triggers of their CI symptoms—therefore guide potential treatment efforts.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]