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1.
J Appl Toxicol ; 44(5): 699-711, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38102769

RESUMO

In ovo exposure to o,p'-dichloro-diphenyl-trichloroethane (o,p'-DDT) impairs reproduction by inducing malformation of the reproductive organs in birds, although the mechanism remains unclear. Here, we examined the effects of o,p'-DDT on the development of the reproductive organs, the expression of genes controlling sexual differentiation, and the plasma concentrations of testosterone and estradiol in Japanese quail embryos. o,p'-DDT-containing sesame oil was injected into the yolk sac on Embryonic Day (E) 3 at a dose of 500, 2,000, or 8,000 µg per egg. On E15, the reproductive organs were observed; the gonads and Müllerian ducts (MDs) were sampled to measure the mRNA of steroidogenic enzymes, sex steroid receptors, anti-Müllerian hormone (AMH), and AMH receptor 2 (AMHR2); blood samples were collected to assay plasma testosterone and estradiol levels; and the gonads were used for histological analysis. o,p'-DDT dose-dependently increased the prevalence of hypertrophic MDs in females and residual MDs in males. In female MDs, o,p'-DDT dose-dependently decreased estrogen receptor (ER) α, ERß, and AMHR2 mRNA expression. o,p'-DDT dose-dependently induced left-biased asymmetry of testis size, and ovary-like tissue was found in the left testis after exposure to 8,000 µg per egg o,p'-DDT, although asymmetric gene expression did not occur. o,p'-DDT did not affect ovarian tissue but did decrease 17α-hydroxylase/C17-20 lyase mRNA expression and dose-dependently increased ERß mRNA expression. o,p'-DDT decreased plasma testosterone concentrations in females. These findings suggest that o,p'-DDT induces hypertrophy of the MDs and ovarian tissue formation in the left testis. Abnormal MD development may be linked to altered gene expression for sensing estrogens and AMH signals.


Assuntos
Coturnix , Diferenciação Sexual , Animais , Masculino , Feminino , Coturnix/genética , Coturnix/metabolismo , Receptor beta de Estrogênio , DDT , Estradiol/metabolismo , Genitália , Testosterona , RNA Mensageiro/genética
2.
Artigo em Inglês | MEDLINE | ID: mdl-37407491

RESUMO

BACKGROUND: Arsenic is a harmful heavy metal and a well-known developmental neurotoxicant. Previously, we have reported that gestational arsenic exposure resulted in impaired social behaviors in F1 and F2 male mice. However, little is known about the developmental arsenic exposure on anxiety-like behavior. This study aimed to detect the effect of gestational arsenic exposure on anxiety-like behavior and related gene expressions in 74-week-old F1 female mice. METHOD: Pregnant C3H/HeN mice (F0) were given drinking water containing 85 ppm sodium arsenite (NaAsO2) from gestational day 8 to 18. The control mice were given tap water only. At 74-week-old, open field test was performed, then anxiety and apoptosis-related factors were determined by real_time RT_PCR and immunohistochemical analyses. RESULTS: The arsenite-exposed F1 female mice showed decreased center entry and center time in open field test. In addition, the number of grooming and fecal pallet was significantly increased in the arsenite-exposed F1 female mice compared to the control. Downregulation of brain-derived neurotrophic factor (BDNF), serotonin receptor (5HT1A) and upregulation of nuclear factor kappa-light-chain-enhancer of activated B cells (NFκB), interleukin 1 ß (IL-1ß), cyclooxygenase 2 (COX2), caspase-3, Bcl2-associated X protein (Bax) were detected in the prefrontal cortex in the arsenite-exposed F1 female mice. Microglial marker ionized calcium-binding adapter molecule 1 (Iba1)-positive cells were increased in the arsenite-exposed F1 female mice. Moreover, a significantly increased plasma corticosterone level was observed in the arsenic-exposed F1 female mice. CONCLUSIONS: This study suggested that gestational arsenic exposure induced anxiety-like behavior accompanied with dysregulation of neurological and immunological markers, neuroinflammatory responses, neuronal apoptosis, and decreased neurogenesis in the prefrontal cortex of F1 female mice.


Assuntos
Arsênio , Arsenitos , Gravidez , Animais , Camundongos , Masculino , Feminino , Arsênio/toxicidade , Arsenitos/toxicidade , Camundongos Endogâmicos C3H , Ansiedade/induzido quimicamente
3.
Int Ophthalmol ; 43(11): 4019-4025, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37420128

RESUMO

PURPOSE: The growing capacity-demand imbalance has necessitated the accelerated digital transformation of eye care services. The role of Oxford Eye Hospital's (OEH) email advice service has become even more relevant in the post-Covid era. We sought to evaluate its impact on referrals to secondary care. METHODS: The consultant-led OEH email advice service primarily targets primary eye care personnel (optometrists and GPs) requiring clinical advice on patient referral. Emails received between September and November 2020 were analysed for demographic data, contents, characteristics, and outcomes. Thematic analysis was performed. A user feedback survey was conducted. RESULTS: A total of 828 emails were received over the 3-month study period (mean 9.1/day). They were predominantly from optometrists (77.9%) and general practitioners (16.1%). Of the 81.0% (671) relating to clinical advice, over half (54.8%) included images from a variety of modalities, and following review, over half (55.5%) were deemed suitable for management in the community, while 36.5% were referred directly to appropriate subspecialty clinics. Only 8.1% required urgent assessment in eye casualty. Thematic analysis showed that this service was most useful for retinal lesions, optical coherence tomography abnormalities, and borderline abnormal optic discs. No adverse events were identified. User feedback was very positive. CONCLUSION: A secure email advice service is a safe and low-maintenance modality that provides direct and efficient two-way communication between primary and secondary eye care professionals. It allows rapid response to clinical queries, referral filtering and refinement, and streamlining of patient referral pathways. Users (predominantly optometrists) were overwhelmingly positive about its usefulness in clinical practice.


Assuntos
COVID-19 , Oftalmologia , Optometria , Humanos , Correio Eletrônico , Encaminhamento e Consulta , Inglaterra
4.
Int J Mol Sci ; 24(1)2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36614034

RESUMO

Recent epidemiological studies have reported significantly increasing hospital admission rates for mental disorders such as anxiety and depression, not only in adults but also in children and adolescents, indicating more research is needed for evaluation of the etiology and possible reduction and prevention of these disorders. The aim of the present study was to examine the associations between perinatal exposure to traffic-related air pollutants and anxiety-like behaviors and alterations in neurological and immunological markers in adulthood using a rat model. Sprague Dawley pregnant rats were exposed to clean air (control), diesel exhaust (DE) 101 ± 9 µg/m3 or diesel exhaust origin secondary organic aerosol (DE-SOA) 118 ± 23 µg/m3 from gestational day 14 to postnatal day 21. Anxiety-related behavioral tests including open field tests, elevated plus maze, light/dark transition tests and novelty-induced hypophagia were performed on 10-week-old rats. The hippocampal expression of neurotransmitters, neurotrophic factors, and inflammatory molecular markers was examined by real-time RT-PCR. Anxiety-like behaviors were observed in both male and female rat offspring exposed to DE or DE-SOA. Moreover, serotonin receptor (5HT1A), dopamine receptor (Drd2), brain-derived neurotrophic factor and vascular endothelial growth factor A mRNAs were significantly decreased, whereas interleukin-1ß, cyclooxygenase-2, heme oxygenase-1 mRNAs and microglial activation were significantly increased in both male and female rats. These findings indicate that brain developmental period exposure to traffic-related air pollutants may induce anxiety-like behaviors via modulation of neurotransmitters, neurotrophic factors, and immunological molecular markers, triggering neuroinflammation and microglia activation in rats.


Assuntos
Poluentes Atmosféricos , Emissões de Veículos , Gravidez , Ratos , Animais , Masculino , Feminino , Emissões de Veículos/toxicidade , Fator A de Crescimento do Endotélio Vascular , Ratos Sprague-Dawley , Ansiedade/etiologia , Neurotransmissores
5.
Int J Mol Sci ; 23(18)2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36142703

RESUMO

Bisphenol S (BPS) is increasingly being used as an alternative for bisphenol A; however, its health effects remain unclear. We investigated the effects of oral exposure to low-dose BPS on allergic asthma. C3H/HeJ male mice were intratracheally administered with allergen (ovalbumin (OVA), 1 µg/animal) every 2 weeks from 6 to 11 weeks old. BPS was ingested by drinking water at doses equivalent to 0.04, 0.4, and 4 µg/kg/day. We then examined pulmonary inflammation, airway hyperresponsiveness, serum OVA-specific immunoglobulin (Ig) levels, Th2 cytokine/chemokine production, and mediastinal lymph node (MLN) cell activities. Compared with OVA alone, moderate-dose BPS (BPS-M) with OVA significantly enhanced pulmonary inflammation, airway hyperresponsiveness, and OVA-specific IgE and IgG1. Furthermore, interleukin (IL)-5, IL-13, IL-33, and CCL11/Eotaxin protein levels in the lungs increased. Conversely, these allergic responses were reduced in the high-dose BPS+OVA group. In MLN cells, BPS-M with OVA increased the total cell count and activated antigen-presenting cells including conventional dendritic cell subset (cDC2). After OVA restimulation, cell proliferation and Th2 cytokine production (IL-4, IL-5, and IL-13) in the culture supernatant also increased. Therefore, oral exposure to low-dose BPS may exacerbate allergic asthmatic responses by enhancing Th2-polarized responses and activating the MLN cells.


Assuntos
Asma , Água Potável , Pneumonia , Hipersensibilidade Respiratória , Alérgenos/metabolismo , Animais , Asma/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Imunoglobulina E , Imunoglobulina G/metabolismo , Interleucina-13/metabolismo , Interleucina-33/metabolismo , Interleucina-4/metabolismo , Interleucina-5 , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Ovalbumina/metabolismo , Fenóis , Pneumonia/metabolismo , Hipersensibilidade Respiratória/metabolismo , Sulfonas , Células Th2
6.
Int J Mol Sci ; 23(2)2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-35054842

RESUMO

Tris (2-butoxyethyl) phosphate (TBEP) is an organophosphate flame retardant and used as a plasticizer in various household products such as plastics, floor polish, varnish, textiles, furniture, and electronic equipment. However, little is known about the effects of TBEP on the brain and behavior. We aimed to examine the effects of dietary exposure of TBEP on memory functions, their-related genes, and inflammatory molecular markers in the brain of allergic asthmatic mouse models. C3H/HeJSlc male mice were given diet containing TBEP (0.02 (TBEP-L), 0.2 (TBEP-M), or 2 (TBEP-H) µg/kg/day) and ovalbumin (OVA) intratracheally every other week from 5 to 11 weeks old. A novel object recognition test was conducted in each mouse at 11 weeks old. The hippocampi were collected to detect neurological, glia, and immunological molecular markers using the real-time RT-PCR method and immunohistochemical analyses. Mast cells and microglia were examined by toluidine blue staining and ionized calcium-binding adapter molecule (Iba)-1 immunoreactivity, respectively. Impaired discrimination ability was observed in TBEP-H-exposed mice with or without allergen. The mRNA expression levels of N-methyl-D aspartate receptor subunits Nr1 and Nr2b, inflammatory molecular markers tumor necrosis factor-α oxidative stress marker heme oxygenase 1, microglia marker Iba1, and astrocyte marker glial fibrillary acidic protein were significantly increased in TBEP-H-exposed mice with or without allergen. Microglia and mast cells activation were remarkable in TBEP-H-exposed allergic asthmatic mice. Our results indicate that chronic exposure to TBEP with or without allergen impaired object recognition ability accompanied with alteration of molecular expression of neuronal and glial markers and inflammatory markers in the hippocampus of mice. Neuron-glia-mast cells interaction may play a role in TBEP-induced neurobehavioral toxicity.


Assuntos
Asma/psicologia , Retardadores de Chama/efeitos adversos , Compostos Organofosforados/efeitos adversos , Ovalbumina/efeitos adversos , Animais , Asma/etiologia , Asma/genética , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Exposição Dietética/efeitos adversos , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Mastócitos/metabolismo , Memória/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C3H , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo , Microglia/metabolismo , Proteínas do Tecido Nervoso/genética , Ovalbumina/imunologia , Estresse Oxidativo/efeitos dos fármacos , Receptores de N-Metil-D-Aspartato/genética
7.
J Appl Toxicol ; 41(10): 1527-1536, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33474794

RESUMO

Bisphenol A (BPA) is a raw material of polycarbonate and epoxy resin. It is used for various household electrical appliances, electronic equipment, office automation equipment, medical equipment, mobile phones, paints for automobiles, internal surface coating of cans, and adhesives for civil engineering and construction. BPA is a well-known endocrine-disrupting chemical, and it was reported that BPA has an adverse effect on the nervous and immune systems. However, BPA-induced memory impairment and changes in neuroimmune biomarkers in the allergic asthmatic subject are not known yet. We aim to investigate the dietary exposure effect of BPA on brain function and biomarkers using allergic an asthmatic mouse model. Five-week-old male C3H/HeJSlc mice were fed two doses of BPA [0.901, 9.01 µg/kg/day] contained chow diet from 5 to 11 weeks old and ovalbumin (OVA) was given by intratracheal instillation every 2 weeks. Memory function was determined by a novel object recognition test. Genes related to memory and immune markers in the hippocampus were investigated with the real-time polymerase chain reaction (RT-PCR) method. In this study, impaired novel object recognition occurred in BPA-exposed mice in the presence of an allergen. Moreover, upregulation of expression level of neuroimmune biomarkers such as N-methyl-D-aspartate receptor, tumor necrosis factor-α, ionized calcium-binding adapter molecule-1, cyclooxygenase-2, and heme oxygenase-1 in the hippocampus was observed in BPA-exposed allergic asthmatic mice. These findings show that BPA exposure can induce neuroinflammation and which triggers impairment of memory function in mice with allergic asthma. Our study indicated that dietary exposure to BPA may affect higher brain functions by modulating neuroimmune biomarkers in allergic asthmatic subjects.


Assuntos
Asma/imunologia , Compostos Benzidrílicos/toxicidade , Exposição Dietética/efeitos adversos , Transtornos da Memória/induzido quimicamente , Neuroimunomodulação/efeitos dos fármacos , Doenças Neuroinflamatórias/induzido quimicamente , Fenóis/toxicidade , Animais , Biomarcadores/sangue , Modelos Animais de Doenças , Disruptores Endócrinos/toxicidade , Hipersensibilidade , Masculino , Camundongos , Camundongos Endogâmicos C3H , Doenças Neuroinflamatórias/imunologia
8.
Immunopharmacol Immunotoxicol ; 43(5): 599-610, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34388063

RESUMO

OBJECTIVE: Tris(1,3-dichloro-2-propyl)phosphate (TDCIPP) is an organophosphorus flame retardant that is an alternative to brominated flame retardants. Although TDCIPP can adversely affect human health, information about its effects on immune and allergic responses is scarce. We aimed to investigate the effects of dietary exposure to TDCIPP using less than the human tolerable daily intake (TDI) in allergic asthmatic mice. METHODS: Male C3H/HeJSlc mice were fed a chow diet containing TDCIPP equivalent to 0.02 µg/kg/day (low; L), 0.2 µg/kg/day (medium; M), or 2 µg/kg/day (high; H) and were intratracheally administered ovalbumin (OVA, 1 µg/animal) every 2 weeks from 5 to 11 weeks of age. RESULTS: In OVA-treated mice, TDCIPP-H exposure tended to enhance pulmonary inflammation compared with vehicle exposure. TDCIPP dose-dependently decreased mRNA level of G protein-coupled estrogen receptor (GPER) in the lungs with or without OVA. OVA + TDCIPP-H treatment tended to increase the total cell number and promoted CD4+ cell activation compared with OVA alone treatment in mediastinal lymph nodes. In splenocytes, an increase in the fraction of Breg cells, but not of total B and T cells, and an increase in IL-5 in cell culture supernatants following OVA re-stimulation in OVA + TDCIPP-H-treated mice was observed compared with OVA-alone-treated mice. Moreover, OVA + TDCIPP-H exposure decreased Gr-1 expression in bone marrow (BM) cells. DISCUSSION: These results suggested that dietary exposure to TDCIPP at TDI level slightly enhances allergic diseases, such as allergic asthma, via GPER regulation at inflamed sites and secondary lymphoid tissue and BM cell alternations.


Assuntos
Asma/induzido quimicamente , Asma/patologia , Exposição Dietética/efeitos adversos , Compostos Organofosforados/administração & dosagem , Compostos Organofosforados/toxicidade , Animais , Asma/metabolismo , Células Cultivadas , Retardadores de Chama/administração & dosagem , Retardadores de Chama/toxicidade , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos C3H , Ovalbumina/toxicidade
9.
Int J Mol Sci ; 22(2)2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33430368

RESUMO

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by impaired social communication, poor social interactions, and repetitive behaviors. We aimed to examine autism-like behaviors and related gene expressions in rats exposed to diesel exhaust (DE)-origin secondary organic aerosol (DE-SOA) perinatally. Sprague-Dawley pregnant rats were exposed to clean air (control), DE, and DE-SOA in the exposure chamber from gestational day 14 to postnatal day 21. Behavioral phenotypes of ASD were investigated in 10~13-week-old offspring using a three-chambered social behavior test, social dominance tube test, and marble burying test. Prefrontal cortex was collected to examine molecular analyses including neurological and immunological markers and glutamate concentration, using RT-PCR and ELISA methods. DE-SOA-exposed male and female rats showed poor sociability and social novelty preference, socially dominant behavior, and increased repetitive behavior. Serotonin receptor (5-HT(5B)) and brain-derived neurotrophic factor (BDNF) mRNAs were downregulated whereas interleukin 1 ß (IL-ß) and heme oxygenase 1 (HO-1) mRNAs were upregulated in the prefrontal cortex of male and female rats exposed to DE-SOA. Glutamate concentration was also increased significantly in DE-SOA-exposed male and female rats. Our results indicate that perinatal exposure to DE-SOA may induce autism-like behavior by modulating molecules such as neurological and immunological markers in rats.


Assuntos
Poluentes Atmosféricos/toxicidade , Transtorno do Espectro Autista/fisiopatologia , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Emissões de Veículos/toxicidade , Aerossóis/toxicidade , Animais , Transtorno do Espectro Autista/induzido quimicamente , Fator Neurotrófico Derivado do Encéfalo/genética , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Heme Oxigenase-1/genética , Humanos , Interleucina-1beta/genética , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/genética , Ratos , Ratos Sprague-Dawley , Receptores de Serotonina/genética
10.
Environ Health Prev Med ; 26(1): 34, 2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33706700

RESUMO

BACKGROUND: Arsenic is a developmental neurotoxicant. It means that its neurotoxic effect could occur in offspring by maternal arsenic exposure. Our previous study showed that developmental arsenic exposure impaired social behavior and serotonergic system in C3H adult male mice. These effects might affect the next generation with no direct exposure to arsenic. This study aimed to detect the social behavior and related gene expression changes in F2 male mice born to gestationally arsenite-exposed F1 mice. METHODS: Pregnant C3H/HeN mice (F0) were given free access to tap water (control mice) or tap water containing 85 ppm sodium arsenite from days 8 to 18 of gestation. Arsenite was not given to F1 or F2 mice. The F2 mice were generated by mating among control F1 males and females, and arsenite-F1 males and females at the age of 10 weeks. At 41 weeks and 74 weeks of age respectively, F2 males were used for the assessment of social behavior by a three-chamber social behavior apparatus. Histological features of the prefrontal cortex were studied by ordinary light microscope. Social behavior-related gene expressions were determined in the prefrontal cortex by real time RT-PCR method. RESULTS: The arsenite-F2 male mice showed significantly poor sociability and social novelty preference in both 41-week-old group and 74-week-old group. There was no significant histological difference between the control mice and the arsenite-F2 mice. Regarding gene expression, serotonin receptor 5B (5-HT 5B) mRNA expression was significantly decreased (p < 0.05) in the arsenite-F2 male mice compared to the control F2 male mice in both groups. Brain-derived neurotrophic factor (BDNF) and dopamine receptor D1a (Drd1a) gene expressions were significantly decreased (p < 0.05) only in the arsenite-F2 male mice of the 74-week-old group. Heme oxygenase-1 (HO-1) gene expression was significantly increased (p < 0.001) in the arsenite-F2 male mice of both groups, but plasma 8-hydroxy-2'-deoxyguanosine (8-OHdG) and cyclooxygenase-2 (COX-2) gene expression were not significantly different. Interleukin-1ß (IL-1ß) mRNA expression was significantly increased only in 41-week-old arsenite-F2 mice. CONCLUSIONS: These findings suggest that maternal arsenic exposure affects social behavior in F2 male mice via serotonergic system in the prefrontal cortex. In this study, COX-2 were not increased although oxidative stress marker (HO-1) was increased significantly in arsnite-F2 male mice.


Assuntos
Arsênio/toxicidade , Arsenitos/toxicidade , Poluentes Ambientais/toxicidade , Expressão Gênica/efeitos dos fármacos , Exposição Materna/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Comportamento Social , Compostos de Sódio/toxicidade , Animais , Comportamento Animal/efeitos dos fármacos , Feminino , Marcadores Genéticos , Masculino , Camundongos , Camundongos Endogâmicos C3H , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , Córtex Pré-Frontal/efeitos dos fármacos , Gravidez , Efeitos Tardios da Exposição Pré-Natal/genética , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Efeitos Tardios da Exposição Pré-Natal/psicologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Serotonina/genética , Serotonina/metabolismo
11.
Environ Health Prev Med ; 26(1): 92, 2021 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-34536991

RESUMO

BACKGROUND: Particulate matter (PM) is recognized as the most harmful air pollutant to the human health. The Yangon city indeed suffers much from PM-related air pollution. Recent research has interestingly been focused on the novel subject of changes in the air quality associated with the restrictive measures in place during the current coronavirus disease-2019 (COVID-19) pandemic. The first case of COVID-19 in Myanmar was diagnosed on March 23, 2020. In this article, we report on our attempt to evaluate any effects of the COVID-19-restrictive measures on the ambient PM pollution in Yangon. METHODS: We measured the PM concentrations every second for 1 week on four occasions at three study sites with different characteristics; the first occasion was before the start of the COVID-19 pandemic and the remaining three occasions were while the COVID-19-restrictive measures were in place, including Stay-At-Home and Work-From-Home orders. The Pocket PM2.5 Sensor [PRO] designed by the National Institute for Environmental Studies (NIES), Japan, in cooperation with Yaguchi Electric Co., Ltd., (Miyagi, Japan) was used for the measurement of the ambient PM2.5 and PM10 concentrations. RESULTS: The results showed that there was a significant reduction (P < 0.001) in both the PM2.5 and PM10 concentrations while the COVID-19-restrictive measures were in place as compared to the measured values prior to the pandemic. The city experienced a profound improvement in the PM-related air quality from the "unhealthy" category prior to the onset of the COVID-19 pandemic to the "good" category during the pandemic, when the restrictive measures were in place. The percent changes in the PM concentrations varied among the three study sites, with the highest percent reduction noted in a semi-commercial crowded area (84.8% for PM2.5; 88.6% for PM10) and the lowest percent reduction noted in a residential quiet area (15.6% for PM2.5; 12.0% for PM10); the percent reductions also varied among the different occasions during the COVID-19 pandemic that the measurements were made. CONCLUSIONS: We concluded that the restrictive measures which were in effect to combat the COVID-19 pandemic had a positive impact on the ambient PM concentrations. The changes in the PM concentrations are considered to be largely attributable to reduction in anthropogenic emissions as a result of the restrictive measures, although seasonal influences could also have contributed in part. Thus, frequent, once- or twice-weekly Stay-At-Home or Telework campaigns, may be feasible measures to reduce PM-related air pollution. When devising such an action plan, it would be essential to raise the awareness of public about the health risks associated with air pollution and create a social environment in which Telework can be carried out, in order to ensure active compliance by the citizens.


Assuntos
Poluição do Ar/análise , COVID-19/epidemiologia , Material Particulado/análise , Humanos , Mianmar/epidemiologia , Pandemias , SARS-CoV-2
12.
J Appl Toxicol ; 40(11): 1498-1510, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32497324

RESUMO

Tris(2-butoxyethyl) phosphate (TBEP) is a major organophosphorus flame retardant and has been widely increasing as a substitute for brominated flame retardants. TBEP may have adverse effects on human health; however, its impact on immune and allergic responses remains largely uncharacterized. In this study, the effects of low-dose TBEP comparable with the level of actual human exposure to that of human tolerable daily intake on allergic asthmatic mice were explored. Five-week-old C3H/HeJSlc male mice consumed a diet containing approximately 0.02, 0.2 or 2 µg/kg/day TBEP and were intratracheally administrated ovalbumin (OVA) (1 µg/mouse every 2 weeks from 5 to 11 weeks of age). Exposure to 2 µg/kg/day TBEP with OVA tended to enhance allergic pulmonary inflammation and significantly elevated mRNA levels of interleukin-5, eotaxin-1 and estrogen receptor alpha (ERα) compared with OVA alone. In mediastinal lymph nodes (MLNs), TBEP (0.2 or 2 µg/kg/day) with OVA significantly increased in total cell number and promoted conventional dendritic cell activation than OVA alone; MLN cell proliferation by OVA restimulation was also enhanced in these groups. In the bone marrow (BM), TBEP (0.02 or 0.2 µg/kg/day) with OVA resulted in a net decrease in total cell number and fraction of CCR2+ Gr-1+ cells; the fraction of Gr-1+ cells increased. In conclusion, oral exposure to low-dose TBEP levels equivalent to tolerable daily intake may exacerbate allergic pulmonary inflammation by promoting a skewed T-helper 2 cell response, upregulation of ERα and dysregulation of both MLN and BM microenvironments.


Assuntos
Asma/induzido quimicamente , Retardadores de Chama/toxicidade , Pulmão/efeitos dos fármacos , Compostos Organofosforados/toxicidade , Administração Oral , Animais , Asma/imunologia , Asma/metabolismo , Medula Óssea/efeitos dos fármacos , Medula Óssea/imunologia , Medula Óssea/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Microambiente Celular , Citocinas/metabolismo , Modelos Animais de Doenças , Retardadores de Chama/administração & dosagem , Imunoglobulina E/sangue , Imunoglobulina G/sangue , Pulmão/imunologia , Pulmão/metabolismo , Linfonodos/efeitos dos fármacos , Linfonodos/imunologia , Linfonodos/metabolismo , Masculino , Camundongos Endogâmicos C3H , Nível de Efeito Adverso não Observado , Compostos Organofosforados/administração & dosagem , Ovalbumina , Fenótipo , Células Th2/efeitos dos fármacos , Células Th2/imunologia , Células Th2/metabolismo
13.
J UOEH ; 42(4): 307-315, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33268607

RESUMO

Assessment of personal exposure to particulate matter with an aerodynamic diameter less than or 2.5 µm (PM2.5) is necessary to study the association between PM exposure and health risk. Development of a personal PM2.5 sensor or device is required for the evaluation of individual exposure level. In this study, we aimed to develop a small-sized, lightweight sensor with a global positioning system (GPS) attached that can measure PM2.5 and PM10 every second to assess continuous personal exposure levels. The participants in this study were apparently healthy housewives (n = 15) and university female teaching staff (n = 15) who live in a high PM2.5 area, Yangon, Myanmar. The average PM2.5 exposure levels during 24 h were 16.1 ± 10.0 µg/m3 in the housewives and 15.8 ± 4.0 µg/m3 in the university female teaching staff. The university female teaching staff showed high exposure concentrations during commuting hours, and had stable, relatively low concentrations at work, whereas the housewives showed short-term high exposure peaks due to differences in their lifestyles. This is the first study to show that a GPS-attached standalone PM2.5 and PM10 Sensor [PRO] can be successfully used for mobile sensing, easy use, continuous measurement, and rapid data analysis.


Assuntos
Exposição Ambiental/análise , Monitoramento Ambiental/instrumentação , Sistemas de Informação Geográfica/instrumentação , Material Particulado/análise , Adulto , Feminino , Humanos , Mianmar , Tamanho da Partícula , Adulto Jovem
14.
Lepr Rev ; 89(2): 102-116, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-37180343

RESUMO

Innovative approaches are required to further enhance leprosy control, reduce the number of people developing leprosy, and curb transmission. Early case detection, contact screening, and chemoprophylaxis currently is the most promising approach to achieve this goal. The Leprosy Post-Exposure Prophylaxis (LPEP) programme generates evidence on the feasibility of integrating contact tracing and single-dose rifampicin (SDR) administration into routine leprosy control activities in different settings. The LPEP programme is implemented within the leprosy control programmes of Brazil, Cambodia, India, Indonesia, Myanmar, Nepal, Sri Lanka and Tanzania. Focus is on three key interventions: tracing the contacts of newly diagnosed leprosy patients; screening the contacts for leprosy; and administering SDR to eligible contacts. Country-specific protocol adaptations refer to contact definition, minimal age for SDR, and staff involved. Central coordination, detailed documentation and rigorous supervision ensure quality evidence. Around 2 years of field work had been completed in seven countries by July 2017. The 5,941 enrolled index patients (89·4% of the registered) identified a total of 123,311 contacts, of which 99·1% were traced and screened. Among them, 406 new leprosy patients were identified (329/100,000), and 10,883 (8·9%) were excluded from SDR for various reasons. Also, 785 contacts (0·7%) refused the prophylactic treatment with SDR. Overall, SDR was administered to 89·0% of the listed contacts. Post-exposure prophylaxis with SDR is safe; can be integrated into the routines of different leprosy control programmes; and is generally well accepted by index patients, their contacts and the health workforce. The programme has also invigorated local leprosy control.

15.
Environ Health Prev Med ; 23(1): 53, 2018 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-30360764

RESUMO

BACKGROUND: Airborne particulate pollution is more critical in the developing world than in the developed countries in which industrialization and urbanization are rapidly increased. Yangon, a second capital of Myanmar, is a highly congested and densely populated city. Yet, there is limited study which assesses particulate matter (PM2.5) in Yangon currently. Few previous local studies were performed to assess particulate air pollution but most results were concerned PM10 alone using fixed monitoring. Therefore, the present study aimed to assess distribution of PM2.5 in different townships of Yangon, Myanmar. This is the first study to quantify the regional distribution of PM2.5 in Yangon City. METHODS: The concentration of PM2.5 was measured using Pocket PM2.5 Sensor (Yaguchi Electric Co., Ltd., Miyagi, Japan) three times (7:00 h, 13:00 h, 19:00 h) for 15 min per day for 5 days from January 25th to 29th in seven townships. Detailed information of eight tracks for PM2.5 pollution status in different areas with different conditions within Kamayut Township were also collected. RESULTS: The results showed that in all townships, the highest PM2.5 concentrations in the morning followed by the evening and the lowest concentrations in the afternoon were observed. Among the seven townships, Hlaingtharyar Township had the highest concentrations (164 ± 52 µg/m3) in the morning and (100 ± 35 µg/m3) in the evening. Data from eight tracks in Kamayut Township also indicated that PM2.5 concentrations varied between different areas and conditions of the same township at the same time. CONCLUSION: Myanmar is one of the few countries that still have to establish national air quality standards. The results obtained from this study are useful for the better understanding of the nature of air pollution linked to PM2.5. Moreover, the sensor which was used in this study can provide real-time exposure, and this could give more accurate exposure data of the population especially those subpopulations that are highly exposed than fixed station monitoring.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Material Particulado/análise , Cidades , Mianmar
16.
J Appl Toxicol ; 36(11): 1496-504, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-26918773

RESUMO

Benzo[a]pyrene (BaP) reportedly has mutagenic and adjuvant activities. We aimed to determine the effects of low-dose BaP administration on allergic airway inflammation and mediastinal lymph node (MLN) cell activation/proliferation in mice. Male C3H/HeJ mice were intratracheally administered ovalbumin (OVA) every 2 weeks and/or BaP (0, 0.05, 1 and 20 pmol per animal per week) once per week for 6 weeks. The cellular profile of bronchoalveolar lavage (BAL) fluid, histological changes, inflammatory cytokines/chemokines in the lungs, OVA-specific immunoglobulin (Ig) in serum and MLN cell activation/proliferation were examined. BaP administration of 20 pmol with OVA enhanced neutrophil and macrophage accumulation in the lungs. Compared with OVA administration, BaP administration with OVA tended to enhance pulmonary eosinophilia and goblet cell hyperplasia. Furthermore, it increased the levels of interleukin (IL)-5, IL-13, IL-33, monocyte chemoattractant protein-1 and eotaxin in the lungs, and OVA-specific IgG1 in serum, although not dose-dependently. Compared with the vehicle group, IL-6 and tumor necrosis factor-alpha levels were higher in the OVA + 1 pmol BaP group and IL-12 production was higher in the OVA + 20 pmol BaP group. Ex vivo studies showed that co-exposure to OVA and BaP activated the MHC class II and CD86 expression in MLN cells. Exposure to BaP with OVA increased IL-4, IL-5 and interferon gamma levels in culture supernatants of OVA-re-stimulated MLN cells. In conclusion, low-dose BaP can, at least in part, enhance allergic airway inflammation by facilitating Th2 responses and activating MLN cells; a high BaP dose may contribute to activating both Th1 and Th2 responses. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Benzo(a)pireno/toxicidade , Poluentes Ambientais/toxicidade , Pulmão/efeitos dos fármacos , Hipersensibilidade Respiratória/induzido quimicamente , Hipersensibilidade Respiratória/imunologia , Animais , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Proliferação de Células/efeitos dos fármacos , Quimiocina CCL2/análise , Relação Dose-Resposta a Droga , Imunoglobulina G/sangue , Interleucinas/análise , Pulmão/imunologia , Pulmão/patologia , Linfonodos/citologia , Linfonodos/imunologia , Masculino , Camundongos Endogâmicos , Ovalbumina/imunologia
17.
Toxicol Sci ; 199(2): 210-226, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38526210

RESUMO

In avian embryos, xenoestrogens induce abnormalities in reproductive organs, particularly the testes and Müllerian ducts (MDs). However, the molecular mechanisms remain poorly understood. We investigated the effects of ethynylestradiol (EE2) exposure on gene expression associated with reproductive organ development in Japanese quail embryos. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) analysis revealed that the left testis containing ovary-like tissues following EE2 exposure highly expressed the genes for steroidogenic enzymes (P450scc, P45017α, lyase, and 3ß-HSD) and estrogen receptor-ß, compared to the right testis. No asymmetry was found in these gene expression without EE2. EE2 induced hypertrophy in female MDs and suppressed atrophy in male MDs on both sides. RNA sequencing analysis of female MDs showed 1,366 differentially expressed genes between developing left MD and atrophied right MD in the absence of EE2, and these genes were enriched in Gene Ontology terms related to organogenesis, including cell proliferation, migration and differentiation, and angiogenesis. However, EE2 reduced asymmetrically expressed genes to 21. RT-qPCR analysis indicated that genes promoting cell cycle progression and oncogenesis were more highly expressed in the left MD than in the right MD, but EE2 eliminated such asymmetric gene expression by increasing levels on the right side. EE2-exposed males showed overexpression of these genes in both MDs. This study reveals part of the molecular basis of xenoestrogen-induced abnormalities in avian reproductive organs, where EE2 may partly feminize gene expression in the left testis, developing as the ovotestis, and induce bilateral MD malformation by canceling asymmetric gene expression underlying MD development.


Assuntos
Coturnix , Etinilestradiol , Regulação da Expressão Gênica no Desenvolvimento , Ductos Paramesonéfricos , Testículo , Animais , Masculino , Testículo/efeitos dos fármacos , Testículo/metabolismo , Testículo/embriologia , Testículo/patologia , Coturnix/embriologia , Coturnix/genética , Etinilestradiol/toxicidade , Ductos Paramesonéfricos/efeitos dos fármacos , Ductos Paramesonéfricos/embriologia , Ductos Paramesonéfricos/anormalidades , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Embrião não Mamífero/efeitos dos fármacos , Feminização/induzido quimicamente , Feminização/genética
18.
Clin Dev Immunol ; 2013: 623812, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24228055

RESUMO

Studies of unexplained symptoms observed in chemically sensitive subjects have increased the awareness of the relationship between neurological and immunological diseases due to exposure to volatile organic compounds (VOCs). However, there is no direct evidence that links exposure to low doses of VOCs and neurological and immunological dysfunction. We review animal model data to clarify the role of VOCs in neuroimmune interactions and discuss our recent studies that show a relationship between chronic exposure of C3H mice to low levels of formaldehyde and the induction of neural and immune dysfunction. We also consider the possible mechanisms by which VOC exposure can induce the symptoms presenting in patients with a multiple chemical sensitivity.


Assuntos
Poluição do Ar em Ambientes Fechados/efeitos adversos , Doença Ambiental/induzido quimicamente , Compostos Orgânicos Voláteis/efeitos adversos , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Formaldeído/efeitos adversos , Expressão Gênica , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Camundongos , Neuroimunomodulação/efeitos dos fármacos , Neurotransmissores/genética , Sistema Hipófise-Suprarrenal/efeitos dos fármacos
19.
Arch Toxicol ; 87(4): 753-62, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23212306

RESUMO

Diazinon is an organophosphate pesticide that is still heavily used in agriculture, home gardening, and indoor pest control in Japan. The present study investigated the effect of neonatal exposure to diazinon on hippocampus-dependent novel object recognition test performance and the expression of the N-methyl-D-aspartate (NMDA) receptor and its signal transduction pathway-related genes in the hippocampi of young adult and adult mice. Male offspring of C3H/HeN mice were subcutaneously treated with 0, 0.5, or 5 mg/kg of diazinon for 4 consecutive days beginning on postnatal day (PND) 8. Beginning on PND 46 or PND 81, a novel object recognition test was performed on 4 consecutive days. The hippocampi were collected on PND 50 or PND 85 after the completion of the novel object recognition test, and the expression levels of neurotrophins and the NMDA receptor and its signal transduction pathway-related genes were examined using real-time RT-PCR. Diazinon-injected mice exhibited a poor ability to discriminate between novel and familiar objects during both the PND 49 and the PND 84 tests. The NMDA receptor subunits NR1 and NR2B and the related protein kinase calcium/calmodulin-dependent protein kinase (CaMK)-IV and the transcription factor cyclic AMP responsive element binding protein (CREB)-1 mRNA levels were reduced in the PND 50 mice. However, no significant changes in the expressions of the NMDA subunits and their signal transduction molecules were observed in the hippocampi of the PND 85 mice. The expression level of nerve growth factor mRNA was significantly reduced in the PND 50 or 85 mice. These results indicate that neonatal diazinon exposure impaired the hippocampus-dependent novel object recognition ability, accompanied by a modulation in the expressions of the NMDA receptor and neurotrophin in young adult and adult mice.


Assuntos
Comportamento Animal/efeitos dos fármacos , Diazinon/toxicidade , Inseticidas/toxicidade , Receptores de N-Metil-D-Aspartato/genética , Reconhecimento Psicológico/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Hipocampo/fisiopatologia , Injeções Subcutâneas , Masculino , Camundongos , Camundongos Endogâmicos C3H , Fatores de Crescimento Neural/genética , Fatores de Crescimento Neural/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Fatores de Tempo
20.
J Appl Toxicol ; 33(10): 1070-8, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23148021

RESUMO

Previously, we demonstrated that maternal exposure to phthalates enhances atopic dermatitis in male mouse offspring. However, whether phthalate exposure affects neuroimmune biomarkers in allergic mice has not yet been studied. Di-(2-ethylhexyl) phthalate (DEHP) and di-isononyl phthalate (DINP) are environmental chemicals that are commonly used as plasticizers. This study was designed to investigate the expression levels of neuroimmune biomarkers in the hypothalamus of a murine model of allergic asthma after phthalate exposure throughout juvenility until adulthood. Six-week-old C3H/HeJ Jcl male mice were treated with DEHP or DINP (0, 0.02, 0.4 or 8 nmol per body per week) and ovalbumin (OVA; 1 µg per body per 2 weeks) for 7 weeks intratracheally. On the day after the completion of the phthalate and OVA treatment, the hypothalamus from each mouse was collected, and the mRNA expression levels of neuroimmune biomarkers were examined using a real-time RT-PCR analysis. The mRNA expression levels of the proinflammatory cytokines interleukin (IL)-1ß and tumor necrosis factor (TNF)-α, the chemokine CCL3, the transcription factor nuclear factor (NF)-κB, the oxidative stress marker heme-oxygenase (HO)1, a nerve growth factor, and the microglia marker Iba1 were remarkably up-regulated in the hypothalami of mice treated with 8 nmol of DEHP in the presence of the allergen. However, no significant changes were observed, except for reductions in the TNF-α and CCL2 mRNA levels, in mice exposed to DINP combined with the allergen. This study is the first report to show that high-dose DEHP exposure throughout juvenility until adulthood may induce neuroinflammation by modulating neuroimmune biomarkers in the hypothalami of allergic mice.


Assuntos
Biomarcadores/metabolismo , Dietilexilftalato/toxicidade , Hipotálamo/efeitos dos fármacos , Inflamação Neurogênica/patologia , Ácidos Ftálicos/toxicidade , Plastificantes/toxicidade , Alérgenos/toxicidade , Animais , Asma/fisiopatologia , Quimiocina CCL3/genética , Quimiocina CCL3/metabolismo , Relação Dose-Resposta a Droga , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Hipotálamo/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C3H , NF-kappa B/genética , NF-kappa B/metabolismo , Inflamação Neurogênica/induzido quimicamente , Ovalbumina/administração & dosagem , Estresse Oxidativo/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima
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