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1.
J Biochem ; 172(6): 365-376, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36200927

RESUMO

Chronic obstructive pulmonary disease (COPD) is a major cause of mortality worldwide, and pulmonary epithelial cell apoptosis is regarded as one of the most important factors in its pathogenesis. Here, we examined the molecular mechanisms of apoptosis caused by cigarette smoke (CS). In the normal bronchial epithelium cell line BEAS-2B, a CS extract markedly induced apoptosis together with transient early growth response 1 (EGR1) protein expression, which is activated over time via the aryl hydrocarbon receptor (AHR). The CS extract-induced apoptosis decreased cell count of BEAS-2B cells and was significantly reversed by knockdown of either EGR1 or AHR. In vivo, the CS extract caused alveolar wall destruction, mimicking COPD, 1 week after intrathoracic injection. Bronchoalveolar lavage fluid (BALF) from the CS extract-treated mice contained massive numbers of apoptotic epithelial cells. Furthermore, it was found that aminoanthracene induced EGR1 expression and cell apoptosis. By contrast, the AHR antagonist stemregenin 1 (SR1) restored apoptosis upon CS treatment. These results suggest that aryl hydrocarbons, such as aminoanthracene, induce EGR1 expression via the AHR, resulting in cell apoptosis and that this can be prevented by administration of an antagonist of AHR.


Assuntos
Proteína 1 de Resposta de Crescimento Precoce , Nicotiana , Doença Pulmonar Obstrutiva Crônica , Fumaça , Animais , Camundongos , Apoptose , Proteína 1 de Resposta de Crescimento Precoce/genética , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Pulmão/metabolismo , Pulmão/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/induzido quimicamente , Doença Pulmonar Obstrutiva Crônica/metabolismo , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo , Nicotiana/efeitos adversos , Fumaça/efeitos adversos , Humanos , Linhagem Celular
2.
Bone Rep ; 16: 101522, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35372643

RESUMO

Despite various reports on the bone healing processes of tooth extraction socket and long bone fracture, the differences of pathological changes during these healing processes remain elusive. This study aims to elucidate the underlying mechanisms behind the pathophysiology of bone regeneration between the tooth extraction socket and femoral fractures through a comparative study. Eight-week-old male mice were used in the experiments. The maxillary first molar was extracted, and intramedullary nailing femoral fracture (semistabilized fracture repair) was performed in the femur. Pathological changes in these bone injuries were investigated by micro-CT, histology, immunohistochemistry, and RT-PCR until day 7 post operation. Pathological changes in drill hole injury created in cortical bone of femur were also examined. Micro-CT analyses revealed increases in mineralized tissues in both the tooth extraction socket and femoral fracture. Histological examinations revealed that tooth socket was repaired by intramembranous ossification, and intramedullary nailing femoral fracture was healed by endochondral ossification. Immunohistochemical investigation revealed that tooth socket healing associated with Sp7-positive cells but not Sox9, aggrecan, and type II collagen, while femoral fracture models exhibited positive signals for all antibodies. RT-PCR analyses revealed the expression of Sp7, Col1a1, and Col2a1 in tooth socket healing, and the expression of Sp7, Col1a1, Runx2, Sox9, Acan, Col2a1, and Col10a1 in intramedullary nailing femoral fracture. Drill hole injury was repaired primarily by intramembranous ossification when the periosteum was removed before making the hole. The present study demonstrated that the absence of cartilage appearance during tooth extraction socket healing indicates it as distinctly different pathological features from the healing processes of semistabilized femoral fracture. This study contributes to the understanding of the molecular and cellular characteristics of bone healing among the different sites of bone injury.

3.
Infect Dis Poverty ; 11(1): 28, 2022 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-35272701

RESUMO

BACKGROUND: Achieving the elimination of soil-transmitted helminth (STH) infections requires a sufficient understanding of the current epidemiological status of STH endemicity. We aimed to examine the status of STH in Myanmar - a country with the eighth highest STH prevalence in the world, 10 years after instigation of the national deworming programme. METHODS: In August 2016 we screened for STH infections using Kato Katz (KK) microscopy and real-time PCR (qPCR) in schoolchildren from the Bago Region township of Phyu, a STH sentinel site in Myanmar. Ten schools were randomly selected, and one stool sample each from a total of 264 students was examined. Prevalence and intensity of infection were calculated for each STH. RESULTS: High prevalence of STH was identified in the study area with 78.8% of the schoolchildren infected with at least one STH by qPCR, and 33.3% by KK. The most prevalent STH was Trichuris trichiura, diagnosed by both KK (26.1%) and qPCR (67.1%), followed by Ascaris lumbricoides (15.5% KK; 54.9% qPCR). No hookworm infections were identified by KK; however, the qPCR analysis showed a high prevalence of Ancylostoma sp. infection (29.6%) with few Necator americanus (1.1%) infections. CONCLUSIONS: Despite bi-annual deworming of schoolchildren in the fourth-grade and below, STH prevalence remains stubbornly high. These results informed the expansion of the Myanmar National STH control programme to include all school-aged children by the Ministry of Health and Sports in 2017, however further expansion to the whole community should be considered along with improving sanitation and hygiene measures. This would be augmented by rigorous monitoring and evaluation, including national prevalence surveys.


Assuntos
Ascaris lumbricoides , Solo , Animais , Criança , Estudos Transversais , Humanos , Mianmar/epidemiologia , Prevalência
4.
Acta Histochem Cytochem ; 54(6): 195-206, 2021 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-35023882

RESUMO

In Myanmar, hepatocellular carcinoma (HCC) is commonly seen in young adult and associated with poor prognosis, while the molecular mechanisms that characterize HCC in Myanmar are unknown. As co-activation of Wnt/ß-catenin signaling and c-Myc (Myc) are reported to associate with malignancy of HCC, we immunohistochemically investigated the expression of Pygo2 and Bcl9, the co-activators of the Wnt/ß-catenin signaling, Myc and PCNA in 60 cases of Myanmar HCC. Pygo2 expression was confirmed by in situ hybridization. The signal intensity was measured by image analyzer and then statistically analyzed. As a result, the expression of Pygo2 was significantly higher in HCC compared to normal liver tissue and the nuclear signal was the most intense in poorly differentiated HCC. Cytoplasmic Bcl9 was expressed in the normal liver tissue but decreased in HCC with the progression of histopathological grade. Myc was significantly higher in poorly differentiated HCC, whereas PCNA labeling index increased with the progression of histopathological grade. Nuclear Pygo2 showed strong correlation with nuclear Myc (P < 0.01) and PCNA (P < 0.001), and inversely correlated with cytoplasmic Bcl9 (P < 0.01). Our results suggested Wnt/ß-catenin and Myc signaling is commonly activated in Myanmar HCC and that the correlative upregulation of nuclear Pygo2 and Myc characterizes the malignant features of HCC in Myanmar.

5.
Histochem Cell Biol ; 151(4): 291-303, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30511269

RESUMO

Diethylstilbestrol (DES), an estrogen agonist, increases prolactin (PRL) cells through transdifferentiation of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) cells to PRL cells as well as proliferation of PRL cells in adult male mouse pituitary. Since hyperacetylation of histone H3 is implicated in the regulation of activation of various genes, we examined the effect of DES on the state of histone H3 acetylation. DES significantly reduced the immunohistochemical signal for acetylated histone H3 at lysine 9 (H3K9ac) in PRL, LH and FSH cells, but not for H3K18ac or H3K23ac. DES-treated mice were injected intraperitoneally with HDAC inhibitors (HDACi), sodium phenylbutyrate (NaPB) or valproic acid (VPA), to mimic the acetylation level of histone H3. As expected, HDACi treatment restored the level of H3K9ac expression in these cells, and also inhibited DES-induced increase in PRL cells. Furthermore, NaPB and VPA also abrogated the effects of DES on the population density of both LH and FSH cells. Similarly, the numbers of proliferating and apoptotic cells in the pituitary in NaPB- or VPA-treated mice were comparable to those of the control mice. Considered together, these results indicated that the acetylation level of histone H3 plays an important role in DES-induced transdifferentiation of LH to PRL cells as well as proliferation of PRL cells.


Assuntos
Transdiferenciação Celular/efeitos dos fármacos , Gonadotrofos/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Lactotrofos/efeitos dos fármacos , Fenilbutiratos/farmacologia , Hipófise/efeitos dos fármacos , Ácido Valproico/farmacologia , Acetilação/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Dietilestilbestrol/administração & dosagem , Dietilestilbestrol/farmacologia , Gonadotrofos/citologia , Inibidores de Histona Desacetilases/administração & dosagem , Histonas/análise , Histonas/biossíntese , Injeções Intraperitoneais , Lactotrofos/citologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Fenilbutiratos/administração & dosagem , Hipófise/metabolismo , Coelhos , Ácido Valproico/administração & dosagem
6.
Malar J ; 16(1): 281, 2017 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-28693552

RESUMO

BACKGROUND: Plasmodium vivax malaria remains a major public health burden in Myanmar. Resistance to chloroquine (CQ), the first-line treatment for P. vivax, has been reported in the country and has potential to undermine local control efforts. METHODS: Patients over 6 years of age with uncomplicated P. vivax mono-infection were enrolled into clinical efficacy studies in Myawaddy in 2014 and Kawthoung in 2012. Study participants received a standard dose of CQ (25 mg/kg over 3 days) followed by weekly review until day 28. Pvmdr1 copy number (CN) and microsatellite diversity were assessed on samples from the patients enrolled in the clinical study and additional cross-sectional surveys undertaken in Myawaddy and Shwegyin in 2012. RESULTS: A total of 85 patients were enrolled in the CQ clinical studies, 25 in Myawaddy and 60 in Kawthoung. One patient in Myawaddy (1.2%) had an early treatment failure and two patients (2.3%) in Kawthoung presented with late treatment failures on day 28. The day 28 efficacy was 92.0% (95% CI 71.6-97.9) in Myawaddy and 98.3% (95% CI 88.7-99.8) in Kawthoung. By day 2, 92.2% (23/25) in Myawaddy and 85.0% (51/60) in Kawthoung were aparasitaemic. Genotyping and pvmdr1 CN assessment was undertaken on 43, 52 and 46 clinical isolates from Myawaddy, Kawthoung and Shwegyin respectively. Pvmdr1 amplification was observed in 3.2% (1/31) of isolates in Myawaddy, 0% (0/49) in Kawthoung and 2.5% (1/40) in Shwegyin. Diversity was high in all sites (H E 0.855-0.876), with low inter-population differentiation (F ST 0.016-0.026, P < 0.05). CONCLUSIONS: Treatment failures after chloroquine were observed following chloroquine monotherapy, with pvmdr1 amplification present in both Myawaddy and Shwegyin. The results emphasize the importance of ongoing P. vivax drug resistance surveillance in Myanmar, particularly given the potential connectivity between parasite population at different sites.


Assuntos
Antimaláricos/farmacologia , Cloroquina/farmacologia , Fluxo Gênico , Variação Genética , Malária Vivax/tratamento farmacológico , Plasmodium vivax/efeitos dos fármacos , Plasmodium vivax/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Estudos Transversais , Variações do Número de Cópias de DNA , Feminino , Genótipo , Humanos , Masculino , Repetições de Microssatélites/genética , Pessoa de Meia-Idade , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Mianmar , Proteínas de Protozoários/genética , Adulto Jovem
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