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1.
Cell Biol Int ; 40(6): 662-70, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26992443

RESUMO

Asymmetric dimethylarginine (ADMA), a high risk factor for endothelial dysfunction and cardiovascular disease (CVD), has been reported to promote cellular dysfunction via endoplasmic reticulum (ER) stress activation in various cells. Additionally, increased serum ADMA levels have been observed in incipient kidney diseases. Previously, we reported that activated ER stress is associated with mesangial cell apoptosis, observed mainly in overt nephropathy or chronic kidney disease (CKD). However, the effect of ADMA on mesangial cell apoptosis is unknown. Thus, we investigated the effects of ADMA on mesangial cell apoptosis and ER stress signaling. ADMA treatment increased caspase-3 activity and activated three branches of ER stress signaling (PERK, IRE1, and ATF6) that induce mesangial cell apoptosis. Pharmacological inhibitors of ER stress (inhibitors of PERK, IRE1, and S1P) attenuated ADMA-induced cleavage of caspase-3 and induced a decrease in the mitochondrial membrane potential. Furthermore, these inhibitors diminished the number of apoptotic cells induced by ADMA treatment. Taken together, our results indicated that ADMA treatment induces mesangial cell apoptosis via ER stress signaling. These results suggest that ADMA-induced mesangial cell apoptosis could contribute to the progression of overt nephropathy and CKD.


Assuntos
Apoptose/efeitos dos fármacos , Arginina/análogos & derivados , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Células Mesangiais/efeitos dos fármacos , Animais , Arginina/farmacologia , Caspase 3/metabolismo , Linhagem Celular Tumoral , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/fisiologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Células Mesangiais/citologia , Proteínas Serina-Treonina Quinases/metabolismo , Ratos , Transdução de Sinais/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/fisiologia
2.
Korean J Parasitol ; 54(1): 103-7, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26951988

RESUMO

The objective of this study was to evaluate the effects of several different commercial disinfectants on the embryogenic development of Ascaris suum eggs. A 1-ml aliquot of each disinfectant was mixed with approximately 40,000 decorticated or intact A. suum eggs in sterile tubes. After each treatment time (at 0.5, 1, 5, 10, 30, and 60 min), disinfectants were washed away, and egg suspensions were incubated at 25˚C in distilled water for development of larvae inside. At 3 weeks of incubation after exposure, ethanol, methanol, and chlorohexidin treatments did not affect the larval development of A. suum eggs, regardless of their concentration and treatment time. Among disinfectants tested in this study, 3% cresol, 0.2% sodium hypochlorite and 0.02% sodium hypochlorite delayed but not inactivated the embryonation of decorticated eggs at 3 weeks of incubation, because at 6 weeks of incubation, undeveloped eggs completed embryonation regardless of exposure time, except for 10% povidone iodine. When the albumin layer of A. suum eggs remained intact, however, even the 10% povidone iodine solution took at least 5 min to reasonably inactivate most eggs, but never completely kill them with even 60 min of exposure. This study demonstrated that the treatment of A. suum eggs with many commercially available disinfectants does not affect the embryonation. Although some disinfectants may delay or stop the embryonation of A. suum eggs, they can hardly kill them completely.


Assuntos
Ascaris suum/efeitos dos fármacos , Desinfetantes/toxicidade , Desenvolvimento Embrionário/efeitos dos fármacos , Animais , Embrião não Mamífero/efeitos dos fármacos , Fatores de Tempo
3.
J Phys Chem C Nanomater Interfaces ; 127(1): 11-21, 2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36660095

RESUMO

Solar powered redox cells (SPRCs) are promising for large-scale and long-term storage of solar-energy, particularly when coupled with redox flow batteries (RFBs). While efforts have primarily focused on heterostructure engineering, the potential of synergistic morphology and photonic design has not been carefully studied. Here, we investigate the wavelength-dependent effects of light-absorption and charge transfer characteristics on the performance of gold decorated TiO2-based SPRC photoanodes operating with RFB-compatible redox couples. Through an in-depth optical and photoelectrochemical characterization of three complementary TiO2 microstructures, namely nanotubes, honeycombs, and nanoparticles, we elucidate the combined effects of nanometer-scale semiconductor morphology and plasmonic design across the visible spectrum. In particular, thin-walled TiO2 nanotubes exhibit a ∼ 50% increase in solar-to-chemical efficiency (STC) compared to thick-walled TiO2 honeycombs thanks to improved charge transfer. Au nanoparticles both increase generation and interfacial charge transfer (above bandgap) and promote hot carrier injection (below bandgap) leading to a further 25% increase in STC. Overall, Au/TiO2 nanotubes achieve a high photocurrent at 0.098 mA/cm2 and an excellent STC of 0.06%, among the highest with respect to the theoretical limit. The incident photon to current efficiency and internal quantum efficiency are also superior to those of bare TiO2 showing maximum values of 54.7% and 67%, respectively. Overall, nanophotonic engineering that synergistically combines morphology optimization and plasmonic sensitization schemes offer new avenues for improving rechargeable solar-energy technologies such as solar redox flow batteries.

4.
Nanoscale ; 13(3): 1997-2004, 2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33443521

RESUMO

Photoelectrochemical water splitting under harsh chemical conditions can be promoted by dispersed transition metal nanoparticles electrodeposited on n-Si surfaces, without the need for classical protection layers. Although this method is simple, it only allows for poor control of metal morphology and geometry on the photoanode surface. Herein, we introduce templated nanoscale electrodeposition on photoactive n-Si for the customization of nanoscale inhomogeneous Schottky junctions and demonstrate their use as stable photoanodes. The photoelectrochemical properties of the so-manufactured photoanodes exhibit a strong dependence on the photoanodes' geometrical features, and the obtained experimental trends are rationalized using simulation.

5.
J Vet Sci ; 8(2): 117-20, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17519563

RESUMO

Cytogenetic and hematological analyses were performed on the peripheral blood lymphocytes (PBLs) obtained from Korean native cattle bred in the vicinity of three nuclear power plants (Wolsong, Uljin and Yeonggwang) and in a control area. The micronucleus (MN) rates for the cattle from the Wolsong, Uljin and Yeonggwang nuclear power plants and for the control area were 9.87 +/- 2.64, 8.90 +/- 3.84, 9.20 +/- 3.68 and 9.60 +/- 3.91 per 1,000 cytokinesis-blocked lymphocytes, respectively. The apparent difference is not statistically significant. The MN frequencies of PBLs from cattle bred in the four areas are within the background variation for this study. The MN frequencies and hematological values were similar regardless of whether the cattle were bred near a nuclear power plant or in the control area.


Assuntos
Bovinos/sangue , Linfócitos/efeitos da radiação , Testes para Micronúcleos/veterinária , Centrais Elétricas , Animais , Contagem de Células Sanguíneas/veterinária , Citocinese , Hematócrito/veterinária , Hemoglobinas/análise , Linfócitos/citologia , Poluentes Radioativos/farmacologia
6.
J Vet Diagn Invest ; 17(5): 490-2, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16312246

RESUMO

Segmental aplasia of the uterine body was diagnosed in a 5-year-old, mixed breed bitch. Abdominal radiography and transabdominal ultrasonography revealed marked dilation of fluid-filled uterine horns with no evidence of a uterine body. Sex hormone assays did not detect the presence of estradiol-17 beta; however, progesterone (2 ng/ml) was found in the serum, indicating anestrus. On gross examination of the reproductive tract, the uterine body was absent, apparently never formed. In its place, a cord-like piece of tissue was identified as an aplastic/dysplastic remnant, connecting the cervix and right uterine horn. The tip of the cord-like piece branched into 5 string-like pieces of tissue, 1 of which was connected to the region dividing the left and right uterine horns. Both the uterine horns were dilated markedly revealing hydrometra. Histologically, uterine body remnant tissues from the endometrium, myometrium, and perimetrium were detected in proximal and distal parts of the uterine body. The string-like piece of tissue connecting the uterine body remnant and the uterine horn consisted of a round cluster of smooth muscle cells surrounding a central core of adipose tissue with blood vessels. It was concluded that the hydrometra observed in both uterine horns was induced by an obstruction resulting from segmental aplasia in the uterine body. This is the first known report of segmental aplasia in the uterine body of a bitch.


Assuntos
Doenças do Cão/patologia , Doenças Uterinas/patologia , Animais , Doenças do Cão/sangue , Doenças do Cão/diagnóstico por imagem , Doenças do Cão/cirurgia , Cães , Estradiol/sangue , Feminino , Histerectomia/veterinária , Progesterona/sangue , Ultrassonografia , Doenças Uterinas/sangue , Doenças Uterinas/diagnóstico por imagem , Doenças Uterinas/cirurgia
7.
Oxid Med Cell Longev ; 2015: 617919, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26583059

RESUMO

Oxidative stress-induced retinal pigment epithelial (RPE) cell damage is involved in the progression of diabetic retinopathy. Arginine methylation catalyzed by protein arginine methyltransferases (PRMTs) has emerged as an important histone modification involved in diverse diseases. Sirtuin (SIRT1) is a protein deacetylase implicated in the onset of metabolic diseases. Therefore, we examined the roles of type I PRMTs and their relationship with SIRT1 in human RPE cells under H2O2-induced oxidative stress. H2O2 treatment increased PRMT1 and PRMT4 expression but decreased SIRT1 expression. Similar to H2O2 treatment, PRMT1 or PRMT4 overexpression increased RPE cell damage. Moreover, the H2O2-induced RPE cell damage was attenuated by PRMT1 or PRMT4 knockdown and SIRT1 overexpression. In this study, we revealed that SIRT1 expression was regulated by PRMT1 but not by PRMT4. Finally, we found that PRMT1 and PRMT4 expression is increased in the RPE layer of streptozotocin-treated rats. Taken together, we demonstrated that oxidative stress induces apoptosis both via PRMT1 in a SIRT1-dependent manner and via PRMT4 in a SIRT1-independent manner. The inhibition of the expression of type I PRMTs, especially PRMT1 and PRMT4, and increased SIRT1 could be therapeutic approaches for diabetic retinopathy.


Assuntos
Estresse Oxidativo , Proteína-Arginina N-Metiltransferases/metabolismo , Sirtuína 1/metabolismo , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Humanos , Peróxido de Hidrogênio/toxicidade , Imuno-Histoquímica , Masculino , Estresse Oxidativo/efeitos dos fármacos , Proteína-Arginina N-Metiltransferases/antagonistas & inibidores , Proteína-Arginina N-Metiltransferases/genética , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Sprague-Dawley , Pigmentos da Retina/metabolismo , Sirtuína 1/genética , Estreptozocina/toxicidade
8.
Can J Vet Res ; 74(1): 71-4, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20357963

RESUMO

Mycoplasma synoviae, a major worldwide pathogen in poultry, causes respiratory tract infection and arthritis in chickens and turkeys. Two major surface antigens of M. synoviae are encoded by a single gene, vlhA (variably expressed lipoprotein and hemagglutinin). The gene product is cleaved post-translationally to yield the lipoprotein major surface protein (MSP) B (MSPB) and the hemagglutinin MSPA. The availability of MSPA as an antigen for serodiagnosis was studied by means of a protein chip based on surface plasmon resonance imaging (SPRi). The diagnostic potential of SPRi for measurement of levels of antibody to MSPA was compared with that of a conventional enzyme-linked immunosorbent assay (ELISA) kit. The results from SPRi, a process that took only 1 h, were similar to those from ELISA. Therefore, MSPA can be used as an antigen for serologic studies, and SPRi, a label-free and high-throughput method, may be a valuable tool in avian serodiagnostic studies.


Assuntos
Anticorpos Antibacterianos/sangue , Proteínas da Membrana Bacteriana Externa/imunologia , Doenças das Aves/diagnóstico , Infecções por Mycoplasma/veterinária , Mycoplasma synoviae/isolamento & purificação , Testes Sorológicos/métodos , Ressonância de Plasmônio de Superfície/métodos , Animais , Doenças das Aves/sangue , Galinhas , Ensaio de Imunoadsorção Enzimática , Hemaglutininas/imunologia , Infecções por Mycoplasma/sangue , Infecções por Mycoplasma/diagnóstico , Mycoplasma synoviae/imunologia , Análise Serial de Proteínas/métodos
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