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1.
Nanotechnology ; 32(48)2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34352739

RESUMO

High surface area nickel oxide nanowires (NiO NWs), Fe-doped NiO NWs andα-Fe2O3/Fe-doped NiO NWs were synthesized with nanocasting pathway, and then the morphology, microstructure and components of all samples were characterized with XRD, TEM, EDS, UV-vis spectra and nitrogen adsorption-desorption isotherms. Owing to the uniform mesoporous template, all samples with the same diameter exhibit the similar mesoporous-structures. The loadedα-Fe2O3nanoparticles should exist in mesoporous channels between Fe-doped NiO NWs to form heterogeneous contact at the interface of n-typeα-Fe2O3nanoparticles and p-type NiO NWs. The gas-sensing results indicate that Fe-dopant andα-Fe2O3-loading both improve the gas-sensing performance of NiO NWs sensors.α-Fe2O3/Fe-doped NiO NWs sensors presented the highest response to 100 ppm ethanol gas (55.264) compared with Fe-doped NiO NWs (24.617) and NiO NWs sensors (3.189). The donor Fe-dopant increases the ground state resistance and the absorbed oxygen content in air.α-Fe2O3nanoparticles in electron depletion region result in the increasing resistance in ethanol gas and decreasing resistance in air. In this way,α-Fe2O3/Fe-doped NiO NWs sensor presents the excellent gas-sensing performance due to the formation of heterogeneous contact at the interface.

2.
Eur Rev Med Pharmacol Sci ; 23(4): 1674-1680, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30840292

RESUMO

OBJECTIVE: It has been clearly demonstrated that autophagy plays a critical role in mechanical ventilation-Induced lung injury (VILI). Herein, we first evaluated the mutual effects of autophagy and c-Src signaling on the lung inflammatory response to mechanical ventilation. MATERIALS AND METHODS: Mice were respectively subjected to a lower or higher lung stretch induced by mechanical ventilation with low (7 mL/kg) or high (28 mL/kg) tidal volume, before measuring the activation of autophagy and c-Src signaling through LC3 lipidation and c-Src phosphorylation, respectively. Bone marrow-derived macrophages (BMDMs) were transfected with Atg5 siRNA and administered to AM-depleted mice to generate an autophagy-deficient phenotype, and c-Src signaling was evaluated by Western blot assay to determine the impact of autophagy on c-Src activation during VILI. Afterwards, the c-Src pathway was then blocked using PP2, prior to the evaluation of polymorphonuclear neutrophils (PMN), total cell counts in BAL fluid, and lung injury scores, in order to elucidate the role of the c-Src pathway in autophagy-mediated VILI. RESULTS: Both LC3-II and p-c-Src were remarkably increased after mechanical ventilation, in a time-dependent and tidal volume-dependent manner. Moreover, c-Src phosphorylation induced by ventilation was significantly compromised in autophagy-deficient mice. On the other hand, LC3-II expression did not change due to c-Src signaling abolishment. But the inflammatory response induced by injurious ventilation was markedly attenuated by PP2 or AM-abolishment, shown by PMN and total cell counts in BAL fluid, as well as lung injury scores. CONCLUSIONS: Our results suggested that autophagy caused VILI via regulating c-Src activation, which implies that c-Src may serve as a promising therapeutic target in VILI.


Assuntos
Autofagia , Inflamação/metabolismo , Pulmão/metabolismo , Macrófagos Alveolares/metabolismo , Lesão Pulmonar Induzida por Ventilação Mecânica/metabolismo , Quinases da Família src/metabolismo , Animais , Inflamação/patologia , Pulmão/patologia , Macrófagos Alveolares/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Lesão Pulmonar Induzida por Ventilação Mecânica/patologia
3.
Diagn Interv Imaging ; 97(9): 843-50, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27316573

RESUMO

PURPOSE: The purpose of this study was to correlate tumor volumetric analysis obtained using magnetic resonance (MR) imaging with disease-free survival in patients with advanced rectal cancer who underwent preoperative chemoradiotherapy (CRT). PATIENTS AND METHODS: Institutional review board approval was obtained and patient informed consent was waived. This study included 74 patients (47 men, 27 women; mean age, 64 years±10 [SD] years) who underwent preoperative CRT and subsequent rectal surgery between January 2007 and December 2010. Two radiologists who were blinded to the clinical outcome measured tumor volume separately on two sets of MR images obtained before and after CRT. Patients were classified into two groups according to the episode of recurrence and recorded disease-free survival. To assess factors relevant to disease-free survival, univariate and multivariate Cox regression analysis were performed for tumor volume reduction ratio, circumferential resection margin, tumor regression grade, and pathologic staging. RESULTS: Tumor volume reduction ratio (P=0.009), circumferential resection margin (P=0.008) and tumor regression grade (P=0.002) were significantly associated with disease-free survival. At multivariate analysis, tumor volume reduction ratio was the single variable that was associated with disease-free survival (P=0.003). Tumor volume reduction ratio was also a reliable parameter with an excellent interobserver correlation between two readers for pre-CRT volume (ICC=0.939; 95%CI: 0.885-0.979; P<0.001) and post-CRT volume (ICC=0.889; 95%CI: 0.845-0.934; P<0.001). CONCLUSIONS: MR volumetric measurement of rectal cancer helps predict disease-free survival in patients with rectal cancer who underwent preoperative CRT.


Assuntos
Adenocarcinoma/patologia , Imageamento por Ressonância Magnética , Neoplasias Retais/patologia , Carga Tumoral , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/mortalidade , Adenocarcinoma/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Quimiorradioterapia Adjuvante , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Margens de Excisão , Pessoa de Meia-Idade , Análise Multivariada , Terapia Neoadjuvante , Recidiva Local de Neoplasia/patologia , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/mortalidade , Neoplasias Retais/terapia
4.
J Int Med Res ; 40(4): 1317-24, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22971483

RESUMO

OBJECTIVE: To investigate relationships between serum levels of retinol binding protein 4 (RBP4) and clinical and metabolic variables in Chinese patients with type 2 diabetes mellitus. METHODS: A total of 513 patients (286 males/227 females) provided clinical and lifestyle data and blood and urine samples for analysis. Patients were stratified into four quartile groups according to serum RBP4 concentrations. RESULTS: RBP4 concentration was independently associated with gender, systolic blood pressure, serum triglyceride and creatinine levels, and estimated glomerular filtration rate (eGFR). Hypertension, dyslipidaemia, micro albuminuria and impaired eGFR (<60 ml/min per 1.73 m2) were significantly more prevalent in patients with the highest RBP4 levels than in those with the lowest levels. Increased serum RBP4 was associated with increased risk of hypertension, dyslipidaemia, micro albuminuria and impaired eGFR after adjusting for gender, age, body mass index and duration of diabetes. CONCLUSION: Serum RBP4 may be a useful marker of overall metabolic control in Chinese patients with type 2 diabetes mellitus.


Assuntos
Diabetes Mellitus Tipo 2/sangue , Proteínas Plasmáticas de Ligação ao Retinol/metabolismo , Adulto , Biomarcadores/sangue , China , Comorbidade , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/metabolismo , Dislipidemias/sangue , Dislipidemias/epidemiologia , Feminino , Taxa de Filtração Glomerular , Humanos , Hipertensão/sangue , Hipertensão/epidemiologia , Incidência , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Insuficiência Renal/sangue , Insuficiência Renal/epidemiologia , Estudos Retrospectivos , Risco , Estatísticas não Paramétricas
5.
J Androl ; 29(4): 440-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18359754

RESUMO

Identification of sperm antigens that elicit immunoglobulin (Ig) production and knowledge of their roles in sperm transport and fertilization may enhance diagnosis and treatment of immunologic infertility. Sperm antigens recognized by a female patient's serum anti-sperm antibodies were characterized using an indirect immunobead-binding test, immunoblot analysis, and immunochemical labeling. The anti-sperm antibodies' effect on sperm function was evaluated by acrosome induction by calcium ionophore. Immunobeads specific for IgG were bound to the head of 79% of motile donor sperm. Immunochemical labeling of antibody-binding sites was restricted to the plasma membrane over the acrosomal crescent. No labeling was observed on the inner acrosomal membrane of acrosome-reacted sperm. The antibodies reacted with 35-, 40-, 47-, and 65-kd proteins extracted from acrosome-intact donor sperm. Sperm incubated in 1:4, 1:8, 1:16, and 1:32 dilutions of anti-sperm antibody-positive serum had similar rates of spontaneous acrosome reaction and significantly lower rates of ionophore-induced acrosome reaction compared with sperm incubated in control serum. These results suggest that sperm antigens recognized by the patient's serum anti-sperm antibodies are restricted to the acrosomal region of the plasma membrane. The antibodies may impair fertility by compromising the sperm's ability to undergo capacitation and/or acrosome reaction.


Assuntos
Acrossomo/imunologia , Antígenos de Superfície/imunologia , Imunoglobulina G/imunologia , Infertilidade Feminina/imunologia , Acrossomo/ultraestrutura , Reação Acrossômica/imunologia , Western Blotting , Feminino , Humanos , Imunoglobulina G/sangue , Imuno-Histoquímica , Infertilidade Feminina/sangue , Masculino , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade , Espermatozoides/imunologia , Espermatozoides/ultraestrutura
6.
Mol Reprod Dev ; 74(9): 1132-40, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17342733

RESUMO

Expression of T-complex testis expressed 5 (Tctex5), an orthologue of protein phosphatase-1 inhibitor-3 (PPP1R11), was enhanced in mouse testis and was also expressed in epididymis and spermatozoa. There were three transcripts of Tctex5 including one brain specific and two common transcripts dominant in mouse testis. Tctex5 protein isoforms (75, 52, 32, 25, and 14.3 kDa) were identified. Isoforms of 75 and 52 kDa were spermatogenic-specific and were found in protein fraction containing nuclei, mitochondria, and flagellum accessory, and also in protein fraction containing mainly membranes. Tctex5 was localized in nuclei of pachytene spermatocytes, round spermatocytes, cytoplasm of Sertoli cells in testis; cilia, secretion bodies and nuclei of epithelial cells and interstitium smooth muscle cells in epididymis; and head and principal piece of tail in epididymal spermatozoa. The results suggested that Tctex5 might be a specific protein phosphatase-1 inhibitor in sperm; various Tctex5 transcripts and isoforms and cellular locations imply its different roles in spermatogenesis. Nuclei-type isoforms (75 and 52 kDa) might take part in nucleus remodeling during spermatogenesis whilst membrane-type isoform (52 kDa) might be responsible for dephosphorylation of proteins during capacitation. The other isoforms might play general roles for all kinds of cell types.


Assuntos
Epididimo/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Nucleares/metabolismo , Espermatozoides/metabolismo , Testículo/metabolismo , Animais , Núcleo Celular/química , Núcleo Celular/metabolismo , Epididimo/química , Masculino , Camundongos , Proteínas Associadas aos Microtúbulos/análise , Proteínas Associadas aos Microtúbulos/genética , Proteínas Nucleares/análise , Proteínas Nucleares/genética , Fosfoproteínas Fosfatases/antagonistas & inibidores , Isoformas de Proteínas/análise , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteína Fosfatase 1 , Capacitação Espermática , Espermatozoides/química , Testículo/química , Transcrição Gênica , Ubiquitina-Proteína Ligases , Região do Complexo-t do Genoma
7.
Microsc Res Tech ; 69(8): 618-23, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16741976

RESUMO

Calcium plays a predominant role regulating many functional processes of spermatogenesis and fertilization. The purpose of the present study is to define the exact location of calcium as well as examine the role it plays during spermatogenesis and sperm capacitation. Testes and epididymides were obtained from adult healthy male hamsters. Spermatozoa were incubated with modified Tyrode's medium up to 4 h at 37 degrees Celsius for sperm capacitation in vitro. Samples of the testes and sperm cells were analyzed by cytochemical techniques to determine the location of calcium and Ca(2+)-ATPase and the percentage of acrosome reactions under light and electron microscopy. The data showed that (1) Sertoli cells exhibited numerous calcium precipitates as large, round, electron-dense bodies distributed throughout the cytoplasm and the mitochondrial matrix. Fine calcium precipitates existed in fewer numbers in the intracellular storage sites of spermatogonia and primary spermatocytes, in sharp distinction to secondary spermatocyte and spermatids, which showed an abundance of large and round calcium precipitates, especially in the mitochondrial matrix of spermatids. More calcium deposits were distributed in the plasma membrane (PM), acrosome membrane, and matrices of the acrosome and mitochondria following capacitation; (2) Ca(2+)-ATPase was found in the endoplasmic reticulum system and PM of noncapacitated spermatozoa as well as Sertoli cells. Capacitated spermatozoa showed a weak signal. These results suggest that the presence of calcium in spermatogenic cells might play a role in cell growth and differentiation during spermatogenesis. The Ca(2+)-ATPase function may be inhibited during capacitation, leading to an increase in acrosomal calcium level and triggering of acrosomal exocytosis.


Assuntos
ATPases Transportadoras de Cálcio/análise , Cálcio/análise , Espermatogônias/metabolismo , Espermatozoides/metabolismo , Animais , Cricetinae , Cricetulus , Histocitoquímica/métodos , Masculino , Microscopia Eletrônica de Transmissão/métodos , Espermatogônias/enzimologia , Espermatogônias/ultraestrutura , Espermatozoides/enzimologia , Espermatozoides/ultraestrutura , Testículo/enzimologia , Testículo/metabolismo , Testículo/ultraestrutura
8.
Arch Androl ; 52(4): 233-8, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16728337

RESUMO

The field of reproductive and developmental biology has been revolutionized by recent advanced studies. These studies indicate that stem cells are capable of forming gametes in vivo and in vitro in both mouse and human. This has provided powerful tools for undertaking new types of reproductive studies, and particularly might provide new technology and novel approaches in assisted reproductive medicine.


Assuntos
Células Germinativas/citologia , Infertilidade Feminina/terapia , Infertilidade Masculina/terapia , Animais , Blastocisto/citologia , Diferenciação Celular , Feminino , Fertilidade/fisiologia , Humanos , Masculino , Camundongos , Oócitos/citologia , Oócitos/fisiologia , Espermatozoides/citologia , Espermatozoides/fisiologia , Células-Tronco/citologia , Células-Tronco/fisiologia
9.
Opt Express ; 13(23): 9211-6, 2005 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-19503120

RESUMO

A series of ZnO microcrystallite films deposited on quartz substrates were annealed at the temperature of 600~1050 masculineC. A well c-axis grown wurtzite ZnO film was obtained at the annealing temperature of 850 masculineC. For the samples annealed above this temperature, the empirical parameter E(0) increased calculated from transmittance spectra, which indicated the changes of the interface of ZnO microcrystallite. Measured by Z-scans, the nonlinear absorption coefficient beta(eff) increased from 1.2x10(2) cm/GW to 1.1x10(3) cm/GW when the annealing temperature rose from 950 masculineC to 1050 masculineC, mainly due to the interfacial state enhancement.

10.
J Nutr ; 130(8): 1920-4, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10917902

RESUMO

Conjugated linoleic acids (CLA) are a group of positional and geometric conjugated dienoic isomers of linoleic acid. The objective of this study was to determine the effects of the cis-9,trans-11 and trans-10,cis-12 isomers of conjugated linoleic acid on lipid composition and gene expression during the differentiation of mouse 3T3-L1 preadipocytes. Treatment of differentiating 3T3-L1 preadipocytes with trans-10,cis-12 conjugated linoleic acid (CLA) resulted in a dose-dependent decrease in the expression of the stearoyl-CoA desaturase 1 gene (SCD1). The expression of other adipocyte genes such as adipose P2 (aP2), fatty acid synthase (FAS), SCD2 and the key adipogenic transcription factors, peroxisome proliferator-activated receptor gamma2 (PPARgamma2) and CCAAT enhancer binding protein alpha (C/EBPalpha), remained elevated. Cells treated with trans-10,cis-12 CLA exhibited smaller lipid droplets, with reduced levels of the major monounsaturated fatty acids, palmitoleate and oleate. By contrast, the cis-9,trans-11 isomer did not alter adipocyte gene expression. Repression of the stearoyl-CoA desaturase gene expression in adipocytes by the trans-10,cis-12 isomer may contribute to the mechanisms by which CLA reduces body fat in mice.


Assuntos
Adipócitos/enzimologia , Regulação Enzimológica da Expressão Gênica , Isoenzimas/genética , Estearoil-CoA Dessaturase/genética , Células 3T3 , Animais , Western Blotting , Ácidos Graxos Monoinsaturados/metabolismo , Isomerismo , Camundongos , RNA Mensageiro/metabolismo , Coelhos , Ratos , Triglicerídeos/metabolismo
11.
Phytother Res ; 13(7): 555-60, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10548745

RESUMO

Enhanced activity of the polyol pathway and oxidative damage have been implicated in the pathogenesis of diabetic cataract. We decided to investigate whether these changes in diabetic lenses could be prevented by the water extract of Phellodendron cortex and Aralia cortex (P55A). Aldose reductase activity was inhibited significantly by the treatment with P55A. Consequently, it caused a dramatic reduction in the high sorbitol contents observed in the lenses of diabetic rats. In addition, the greatly elevated content of thiobarbituric acid reactive substances (TBARS) and carbonylated protein in diabetic rats were reduced by P55A treatment. These results suggest that P55A extract exerts an antioxidant effect by reducing lipid peroxidation and protein carbonylation as well as having an inhibitory action against aldose reductase in the lenses of diabetic rats.


Assuntos
Catarata/metabolismo , Diabetes Mellitus Experimental/complicações , Cristalino/patologia , Estresse Oxidativo , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Polímeros/metabolismo , Aldeído Redutase/metabolismo , Animais , Catarata/tratamento farmacológico , Catarata/etiologia , L-Iditol 2-Desidrogenase/metabolismo , Cristalino/enzimologia , Masculino , Extratos Vegetais/uso terapêutico , Ratos , Ratos Sprague-Dawley , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
12.
J Rheumatol ; 25(12): 2408-16, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9858438

RESUMO

OBJECTIVE: Anterior uveitis frequently occurs in association with specific systemic inflammatory diseases. Interleukin 1 (IL-1) and tumor necrosis factor-alpha (TNF-alpha) have been implicated in the pathogenesis of these diseases. We evaluate the need for these cytokines in a model of anterior uveitis. METHODS: Endotoxin was injected into the vitreous of mice deficient in IL-1 receptor type I, TNF receptors p55 and p75, both IL-1R1 and TNFR p55, or controls. Eyes were harvested after 24 h for histology and IL-6 bioassays or after 3 h for reverse transcriptase-polymerase chain reaction analysis of mRNA for specific cytokines or enzymes. RESULTS: No significant difference in the number of infiltrating cells was found in TNFR p55/p75 deficient mice compared to controls in any of 4 separate experiments or in the combined data (p = 0.8). The number of infiltrating cells was significantly reduced in 2 of 4 experiments with IL-1R1 deficient mice (p < 0.001 based on combined data from 4 studies). IL-1R1/TNFR p55 deficient mice had a reduction in infiltrating cells in 2 of 3 experiments (p < 0.001 based on combined data from all studies). IL-6 levels were not significantly reduced in either of 2 experiments with TNFR p55/p75 deficient mice, but were reduced in one of 2 experiments with IL-1R1-/- mice (p = 0.02) and in one experiment with IL-1R1/TNFR p55 deficient mice (p = 0.01). In response to endotoxin, all 3 receptor deficient lines increased mRNA levels for IL-1-alpha, IL-10, TNF-alpha, IL-1 receptor antagonist, and inducible nitric oxide synthase. CONCLUSIONS: IL-1 appears to have a more pivotal role in endotoxin induced uveitis than TNF-alpha, although neither cytokine is essential. Deletion of receptors for both cytokines has the most consistent effect, which is in accord with the hypothesis that these cytokines are, at least in part, functionally redundant.


Assuntos
Endotoxinas/efeitos adversos , Fator de Necrose Tumoral alfa/efeitos dos fármacos , Uveíte Anterior/metabolismo , Animais , Humor Aquoso/efeitos dos fármacos , Humor Aquoso/metabolismo , Modelos Animais de Doenças , Endotoxinas/administração & dosagem , Feminino , Expressão Gênica/efeitos dos fármacos , Interferon gama/genética , Proteína Antagonista do Receptor de Interleucina 1 , Interleucina-1/genética , Interleucina-1/farmacologia , Interleucina-10/genética , Interleucina-6/genética , Interleucina-6/metabolismo , Queratinócitos/citologia , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase Tipo II , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Interleucina-1/deficiência , Receptores de Interleucina-1/genética , Receptores do Fator de Necrose Tumoral/deficiência , Receptores do Fator de Necrose Tumoral/genética , Sialoglicoproteínas/genética , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Uveíte Anterior/induzido quimicamente , Uveíte Anterior/genética , Corpo Vítreo/efeitos dos fármacos , Corpo Vítreo/metabolismo , Corpo Vítreo/patologia
13.
Curr Eye Res ; 17(9): 941-6, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9746442

RESUMO

PURPOSE: Multiple adhesion molecules of the selectin, integrin, and immunoglobulin-like families are involved in the migration of leukocytes out of the bloodstream into inflamed tissues. This study addresses the question of which adhesion molecules are specifically involved in endotoxin-induced uveitis. METHODS: Mice genetically deficient in p-selectin, ICAM-1, beta2-integrin, or controls received intravitreal injections of endotoxin. Eyes were harvested 24 h later and inflammation was evaluated by histologic and immunohistochemical assays of infiltrating cells. RESULTS: Mice lacking either P-selectin or beta2-integrin had less inflammation than controls (median cells/section: 64 for P-selectin knockout vs 130 for controls, p=0.02, n=17 per group: 244 for beta2-integrin knockouts, n=14, vs 355 for controls, n=17, p=0.05). Neither gene deletion significantly changed the ratio of infiltrating neutrophils to macrophages. ICAM-1 knockouts tended to have fewer infiltrating cells (median 22 cells/section) compared to controls (median 132 cells/section), but this difference was not statistically significant (p=0.25, n=9 per group). CONCLUSIONS: P-selectin, beta2-integrin, and possibly ICAM-1 are involved in the ocular inflammatory response to endotoxin. The lack of complete inhibition of leukocyte infiltration with the complete loss of each adhesion molecule is in accord with the notion that alternative adhesion molecules also participate in this process.


Assuntos
Antígenos CD18/metabolismo , Endotoxinas , Escherichia coli , Molécula 1 de Adesão Intercelular/metabolismo , Selectina-P/metabolismo , Uveíte/metabolismo , Animais , Antígenos CD18/genética , Corpo Ciliar/metabolismo , Feminino , Deleção de Genes , Técnicas Imunoenzimáticas , Molécula 1 de Adesão Intercelular/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Selectina-P/genética , Epitélio Pigmentado Ocular/metabolismo , Uveíte/induzido quimicamente , Uveíte/patologia , Corpo Vítreo/metabolismo
15.
Drug Metab Dispos ; 26(1): 66-72, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9443855

RESUMO

The effects of acriflavine (ACF), a protein kinase C inhibitor, on the expression of hepatic microsomal epoxide hydrolase (mEH), glutathione S-transferases (GSTs), and cytochrome P450 (P450) were assessed in rat hepatic tissue. Northern blot analysis revealed that treatment of rats with thiazole, allyl disulfide (ADS), oltipraz, or clotrimazole at a single dose of 100 mg/kg resulted in 7-18-fold increases in mEH mRNA levels at 24 hr, whereas concomitant ACF treatment (20 mg/kg, im) caused 50-95% inhibition of the chemical-induced increases in hepatic mEH mRNA levels. rGSTA2, rGSTA3, and rGSTM1 mRNA levels were also significantly suppressed at 24 hr in response to a single dose of ACF (20 mg/kg, im). Animals treated with both ACF and ADS showed complete blockage of mEH and GST gene expression as early as 12 hr after treatment. ADS-inducible increases in mEH and rGSTA2 mRNA levels were suppressed at 24 hr after treatment with ACF, in a dose-related manner, with 50% inhibitory dose (ID50) values of 2.0-2.3 mg/kg, whereas glyceraldehyde-3-phosphate dehydrogenase mRNA levels were not altered. Immunoblot analysis revealed that ACF (15 mg/kg/day, im, for 3 days) inhibited induction of mEH or rGSTA2 protein by ADS (100 mg/kg/day, po, for 3 days). The levels of hepatic P450 2B1/2, P450 2C11, and P450 3A1/2 were decreased in rats treated with ACF (15 mg/kg/day, im, for 3 days), whereas P450 1A2 and P450 2E1 expression was not affected. Treatment of rats with ACF in combination with gadolinium chloride, which inhibits mEH and GST expression through calcium channel blocking, shifted the dose-inhibitory response curves for ACF to the left, with 7-15-fold decreases in the ID50 values, indicating that the active site for ACF for suppression of mEH and GST mRNA levels differs from that for gadolinium chloride. Proflavine and safranine O, which are structurally related to ACF, also caused suppression of ADS-induced increases in mRNA levels, in a dose-dependent manner, with ID50 values of 4-9 mg/kg. These results demonstrate that ACF and its related compounds effectively suppress the expression of a battery of hepatic xenobiotic-metabolizing enzymes, including mEH, GSTs, and certain P450 forms.


Assuntos
Acriflavina/farmacologia , Enzimas/efeitos dos fármacos , Enzimas/genética , Corantes Fluorescentes/farmacologia , Proteína Quinase C/antagonistas & inibidores , Acriflavina/administração & dosagem , Acriflavina/química , Animais , Anti-Inflamatórios/farmacologia , Antineoplásicos/farmacologia , Inibidores das Enzimas do Citocromo P-450 , Sistema Enzimático do Citocromo P-450/genética , Relação Dose-Resposta a Droga , Epóxido Hidrolases/antagonistas & inibidores , Epóxido Hidrolases/genética , Corantes Fluorescentes/administração & dosagem , Gadolínio/farmacologia , Expressão Gênica , Regulação Enzimológica da Expressão Gênica , Glutationa Transferase/antagonistas & inibidores , Glutationa Transferase/genética , Immunoblotting , Masculino , Fenazinas/farmacologia , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Fatores de Tempo , Xenobióticos/farmacologia
16.
Invest Ophthalmol Vis Sci ; 39(1): 64-9, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9430546

RESUMO

PURPOSE: Interleukin-6 (IL-6) has been strongly implicated in anterior uveitis based on its presence in aqueous humor from infected eyes and its inflammatory effects when injected intravitreally into rats. We used IL-6-deficient mice to test further the hypothesis that IL-6 contributes to the development of endotoxin-induced uveitis. METHODS: Uveitis was scored by histologic analysis of C3H/HeN mice 24 hours after intravitreal injections of up to 200 ng of recombinant murine IL-6. Uveitis was similarly measured in IL-6-deficient mice and congenic controls 24 hours after intravitreal injection of 250 ng of Escherichia coli endotoxin. Reverse transcription-polymerase chain reaction was used to detect mRNAs for several cytokines at 3 hours postinjection. The IL-6 concentration in aqueous humor samples was determined with a bioassay using the murine B9 plasmacytoma cell line. RESULTS: Direct injection of IL-6 did not induce uveitis. Mice genetically deficient in IL-6 developed endotoxin-induced uveitis that was comparable or more severe than congenic control mice. Compensatory changes in the expression of mRNA for other cytokines were not detected in irises from the IL-6-deficient mice. In IL-6-competent mice that received bilateral endotoxin injections, no correlation was found between the number of infiltrating cells in one eye and the IL-6 concentration in the aqueous humor of the contralateral eye. CONCLUSIONS: In marked contrast to previous conclusions with rats, IL-6 was not sufficient for inducing uveitis in mice. Additionally, IL-6 was not necessary for the development of uveitis subsequent to intravitreal injection of endotoxin in mice.


Assuntos
Endotoxinas , Escherichia coli , Deleção de Genes , Interleucina-6/fisiologia , Uveíte Anterior/fisiopatologia , Animais , Humor Aquoso/metabolismo , Citocinas/metabolismo , Primers do DNA/química , Interleucina-6/deficiência , Interleucina-6/genética , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Mutantes/genética , Reação em Cadeia da Polimerase , Transcrição Gênica , Uveíte Anterior/induzido quimicamente , Uveíte Anterior/genética , Uveíte Anterior/metabolismo
17.
J Investig Med ; 45(5): 295-301, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9250003

RESUMO

BACKGROUND: Humans with the major histocompatibility antigen B27 (HLA-B27) are especially at risk for developing rheumatic disorders such as ankylosing spondylitis and Reiter's syndrome. Acute anterior uveitis (AAU) often occurs in association with these diseases or in HLA B27 positive individuals without joint disease. METHODS: We induced acute anterior uveitis in Lewis rats by a standard model, the intraperitoneal injection of 200 micrograms of Escherichia coli endotoxin. We also developed a novel model of uveitis secondary to gram-negative infection. RESULTS: Transgenic rats that expressed a low copy number of the B27 gene did not differ statistically from litter mate controls in the intensity of anterior uveitis as judged by histology, enumeration of cells in aqueous humor, protein in aqueous humor, or slit lamp examination. The majority of rats exposed to live Salmonella enteritidis or Yersinia enterocolitica 0:3 using either an oral or intravenous route of infection developed anterior uveitis. In contrast to the disease induced by endotoxin that is most intense 24 hours after the endotoxin challenge, uveitis induced by live bacteria usually began 7 to 9 days after exposure to bacterial products, was more often unilateral, persisted for as long as 3 weeks, and was sometimes recurrent. The expression of HLA-B27 did not appear to influence the incidence or severity of uveitis in B27+ low copy heterozygous animals. CONCLUSION: This rat model of AAU should facilitate evaluation of bacterial antigenic component(s) involved in the pathogenesis of live gram-negative bacteria induced AAU.


Assuntos
Modelos Animais de Doenças , Antígeno HLA-B27/análise , Uveíte Anterior/imunologia , Doença Aguda , Animais , Animais Geneticamente Modificados , Ratos , Ratos Endogâmicos F344 , Ratos Endogâmicos Lew , Salmonelose Animal/imunologia , Salmonella enteritidis , Uveíte Anterior/microbiologia , Yersiniose/imunologia , Yersinia enterocolitica
18.
J Pharm Pharmacol ; 49(2): 216-22, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9055199

RESUMO

The anti-tumour activity of acriflavine in combination with guanosine has been evaluated in solid or ascitic tumour-implanted animal models. Guanosine is known to potentiate the anti-tumour effects of some chemotherapeutic agents. Administration of acriflavine (15 mg kg-1 day-1, i.m., 14 days) to ICR mice subcutaneously implanted with Ehrlich carcinoma resulted in approximately 30% inhibition in tumour growth. In contrast, minor tumour growth inhibition was observed in animals treated with guanosine at the same daily dose. Treatment of animals with both acriflavine and guanosine (AG60, 1:1, w/w) at 30 mg kg-1 resulted in approximately 65% inhibition in tumour growth rate. Whereas treatment with acriflavine or guanosine resulted in 70% or 30% decrease in tumour weight, respectively, treatment of tumour-implanted mice with AG60 (30 mg kg-1) resulted in a 96% decrease in tumour weight, relative to control, 14 days after tumour-cell implantation. Dose-related inhibition in tumour growth rate was also observed in animals treated with AG60, with maximum (65%) inhibition noted at a dose of 30 mg kg-1 (ED50 23 mg kg-1). Suppression of body weight increase and elevated plasma glucose levels by acriflavine or AG60 indicated that glucose utilization might be impaired. The anti-tumour effect of AG60 was also determined in CDF1 mice intraperitoneally implanted with Ehrlich ascitic tumour. Ehrlich ascitic tumour proliferation was completely suppressed by AG60 (30 mg kg-1, i.p.). Microscopic analyses of intraperitoneal touch-prints revealed that AG60 was more effective in suppressing tumour proliferation than acriflavine alone. Fluorescent microscopic examinations demonstrated that acriflavine avidly bound with Yac-1 cell plasma membrane, leading to morphological changes in the cells, such as bleb formations, swelling and ballooning. The time-related changes in tumour cell morphology by acriflavine or AG60 might represent energy depletion, followed by osmotic lysis as a result of cationic influx. Enhanced anti-tumour activity of acriflavine in combination with guanosine might be explained by the blocking of nutrient transport through selective acriflavine binding with plasma membrane and by concomitant guanosine perturbation of cellular ATP production. This study demonstrates that guanosine enhances the anti-tumour effects of acriflavine against a variety of cancer cells without serious adverse effects, providing a preclinical basis for potential application of this combination against cancer proliferation.


Assuntos
Acriflavina/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Guanosina/uso terapêutico , Acriflavina/administração & dosagem , Animais , Glicemia/efeitos dos fármacos , Carcinoma de Ehrlich/tratamento farmacológico , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Guanosina/administração & dosagem , Leucemia P388 , Masculino , Camundongos , Camundongos Endogâmicos ICR , Células Tumorais Cultivadas/efeitos dos fármacos
19.
Korean J Parasitol ; 34(3): 197-206, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8843696

RESUMO

Water extract of Coix lacryma seeds (Co-Ex) was separated into several components; dissolved with Tris-Cl buffer and the supernatant (WC1), ammonium sulfate treatment supernatant (WC2) and the pellet (WC3), QAE column chromatography of WC1 and the peak portions; WC4, WC5 and WC6. Murine peritoneal macrophages in DMEM containing 10% heat-inactivated FCS were infected with tachyzoites of Toxoplasma gondii, RH strain, in vitro. By adding modulators such as Co-Ex, WC1,2,3,4,5,6 and LPS or IFN-gamma for 24 hrs, toxoplasmastatic activity of macrophages was examined in relation to nitrite production. Nitrite production of macrophages was enhanced especially in the series of WC2, WC1 and the combination sample (WC1+WC2+WC3) by order, than other components or fractions (WC4, WC5, WC6) tested. Toxoplasmastatic actions such as percentage of the macrophages infected by T. gondii and fold increase of T. gondii in macrophages showed retroverse relations with the amount of nitrite production; i.e., as nitric oxide (NO) increased the phagocytic index of macrophages and the fold increase of tachyzoites in macrophages decreased. Nitrite (NO2) production was increased by adding IFN-gamma in all cases together with enhancement of biostatic effects. Through the results obtained, it is speculated that some components other than the non-proteinous and defatted components in Coix lacryma seeds may contribute to activate macrophages through induction of NO for the biostatic activity.


Assuntos
Macrófagos Peritoneais/parasitologia , Extratos Vegetais/farmacologia , Plantas Medicinais , Toxoplasma/efeitos dos fármacos , Animais , Células Cultivadas , Macrófagos Peritoneais/metabolismo , Camundongos , Óxido Nítrico/metabolismo
20.
Arch Pharm Res ; 17(2): 115-8, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10319142

RESUMO

This paper describes the isolation of isoguanosine from Croton tiglium L. and its cytotoxic effect against several tumor cell lines in culture and newly reports that isoguanosine has an antitumor activity against implanted S-180 ascitic tumor mice. Isoguanosine is effective at the dose of 24 mg/kg/day x 5, with T/C value of 168%. Isoguanosine inhibits the growth of S-180 and Ehrlich solid tumor in mice at the optimal doses of 96 mg/kg/day x 12 and 48 mg/kg/day x 12, with 1-T/C values of 65% and 60%, respectively.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Guanosina/isolamento & purificação , Plantas Medicinais/química , Adenosina , Animais , Antineoplásicos Fitogênicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Guanosina/farmacologia , Humanos , Masculino , Camundongos , Transplante de Neoplasias , Células Tumorais Cultivadas
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