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1.
Br Poult Sci ; 61(1): 22-25, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31615265

RESUMO

1. This experiment investigated the influence of chicken PRDX3 on cell proliferation in chick embryo fibroblast cells using PRDX3 knockdown technology.2. A methyl thiazolyl tetrazolium (MTT) assay was performed to assess the effect of chPRDX3 knockdown on fibroblast proliferation. The antioxidant effect was investigated to determine if it directly mediated fibroblast cell proliferation.3. To determine the role of chPRDX3 on cell proliferation, an siRNA mediated knockdown was performed in chick fibroblast cells using an in vitro assay. The proliferation of fibroblast cells transfected with siPRDX3 #3 and siPRDX3 Mix was significantly decreased after 48 h (P < 0.01). In addition, the knockdown of chicken PRDX3 suppressed cell proliferation through an increase in oxidative stress.4. The results demonstrated that chPRDX3 is required for cell proliferation in chicken fibroblast cells. Such findings have important implications for the maintenance of chicken fibroblast cells.


Assuntos
Galinhas , Peroxirredoxina III , Animais , Proliferação de Células , Embrião de Galinha , Fibroblastos , RNA Interferente Pequeno
2.
Poult Sci ; 96(3): 710-716, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-27697932

RESUMO

The use of chlorella as an immune stimulant to enhance nonspecific host defense mechanisms or as an antimicrobial to inhibit bacterial growth has been reported. Thus, the aim of the present study was to clarify the effect of recombinant chlorella supplementation on growth performance, meat quality, and the blood profile, excreta microflora, and nutrient digestibility in broilers. A total of 375 one-day-old ROSS 308 broilers (male and female) were allotted to 5 dietary treatments using 5 cages with 15 chicks per cage. Treatments were: 1) NC, basal diet supplemented with 1.0% E. coli fermented liquor (EFL); 2) PC1, 0.2% EFL with chlorella; 3) PC2, 1.0% EFL with chlorella; 4) T1, 0.2% EFL with chlorella (anti-viral); and 5) T2, 1.0% EFL with chlorella (anti-viral). The broilers in the T2 treatment groups showed higher body weight gain (BGW) by 2.55% (P < 0.01) and lower feed conversion ratio (FCR) by 2.75% (P < 0.05) compared with those fed the control NC treatment group. Moreover, the blood contents of blood urea nitrogen (BUN), creatinine, and IgA in the broilers of the T2 treatment group were significantly increased by 28.12, 23.07, and 29.72%, respectively -more than those found in the broilers of the NC treatment group (P < 0.01). In contrast, the LDL/C in the blood from the animals in the T2 treatment group was significantly decreased by 23.23% - more than that in the blood from the NC broilers (P < 0.05). Based on these results, we suggest that the dietary supplementation of broilers with recombinant chlorella could improve their growth performance, increase the concentration of IgA and apparently metabolizable nitrogen in the blood, and decrease ammonia emissions. Therefore, our findings have important implications for the effect of recombinant chlorella supplementation through increasing the concentration of IgA and the level of metabolizable nitrogen.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Galinhas/fisiologia , Chlorella , Suplementos Nutricionais , Digestão/fisiologia , Fezes/microbiologia , Carne/normas , Ração Animal/análise , Animais , Galinhas/sangue , Galinhas/crescimento & desenvolvimento , Galinhas/microbiologia , Chlorella/química , Chlorella/genética , Dieta/veterinária , Suplementos Nutricionais/análise , Feminino , Masculino , Carne/análise , Distribuição Aleatória , Anticorpos de Cadeia Única
3.
Int J Cosmet Sci ; 38(5): 524-34, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27139639

RESUMO

OBJECTIVE: Bifunctional alpha-bisabolol and phenylethyl resorcinol/TiO2 hybrids were prepared to apply in cosmetic fields, particularly in anti-ageing and hyperpigmentation treatment. The synergistic effect of combined antioxidant and UV filtering properties was achieved through functionalization of TiO2 particles with skin-lightening materials such as alpha-bisabolol and phenylethyl resorcinol. METHODS: TiO2 microspheres with a diameter of about 1 µm were synthesized through surfactant-assisted sol-gel method for use as supporting materials in the formation of hybrid composites. Carboxylation treatment was performed for surface modification of the TiO2 surface with carboxyl groups as chemical binders. Esterification reaction between carboxyl groups of carboxylated TiO2 and hydroxyl groups of alpha-bisabolol or phenylethyl resorcinol was performed. The hybrids were characterized using various techniques such as FE-SEM, DLS, EDS, ATR-FTIR, XPS and TGA. For application of prepared TiO2 composites in the field of cosmetics, the anti-radicular antioxidant abilities were evaluated using ABTS and DPPH colorimetric antioxidant assay. RESULTS: Organic/inorganic hybrid composites were successfully formed using esterification reaction between the carboxyl groups at TiO2 surface and the hydroxyl groups of the skin-lightening materials. The results demonstrate that both functionalized microspheres show scavenging ability towards the ABTS(•) and DPPH(•) radicals. Specifically, the phenylethyl resorcinol/TiO2 composites exhibited the highest antioxidant ability among the prepared samples owing to the presence of phenolic groups to scavenge free radicals. CONCLUSION: Using this strategy, it could be possible to prepare not only inorganic UV filter but also hybrid organic/inorganic materials with multifunctions and advantages which would be in a great demand for cosmetic applications.


Assuntos
Cosméticos , Resorcinóis/química , Sesquiterpenos/química , Titânio/química , Antioxidantes/química , Microscopia Eletrônica de Varredura , Sesquiterpenos Monocíclicos , Espectrometria por Raios X , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
4.
Oncogene ; 35(31): 4091-101, 2016 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-26686094

RESUMO

Solar ultraviolet (UV) light is a major etiological factor in skin carcinogenesis, with solar UV-stimulated signal transduction inducing pathological changes and skin damage. The primary sensor of solar UV-induced cellular signaling has not been identified. We use an experimental system of solar simulated light (SSL) to mimic solar UV and we demonstrate that Fyn is a primary redox sensor involved in SSL-induced signal transduction. Reactive oxygen species (ROS) generated by SSL exposure directly oxidize Cys488 of Fyn, resulting in increased Fyn kinase activity. Fyn oxidation was increased in mouse skin after SSL exposure and Fyn-knockout mice formed larger and more tumors compared with Fyn wild-type mice when exposed to SSL for an extended period of time. Murine embryonic fibroblasts (MEFs) lacking Fyn and cells in which Fyn expression was knocked down were resistant to SSL-induced apoptosis. Furthermore, cells expressing mutant Fyn (C448A) were resistant to SSL-induced apoptosis. These findings suggest that Fyn acts as a regulatory nexus between solar UV, ROS and signal transduction during skin carcinogenesis.


Assuntos
Neoplasias Induzidas por Radiação/etiologia , Proteínas Proto-Oncogênicas c-fyn/fisiologia , Transdução de Sinais/efeitos da radiação , Neoplasias Cutâneas/etiologia , Animais , Apoptose , Células Cultivadas , Camundongos , Camundongos Pelados , Proteína Quinase C-delta/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Raios Ultravioleta
5.
Vox Sang ; 107(4): 407-15, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25130876

RESUMO

BACKGROUND AND OBJECTIVES: Collection of sufficient CD34+ cells for autologous peripheral blood stem cell (PBSC) transplantation is frequently failed in patients with lymphoma or multiple myeloma (MM). We investigated the incidence and the predictive factors for poor mobilization. MATERIALS AND METHODS: A total of 205 adult patients (101 lymphoma and 104 MM) were retrospectively included for identifying the incidence of mobilization failure and the predictive factors for poor mobilization in conventional G-CSF-based mobilization regimen. Another 17 patients who used plerixafor for mobilization were included. RESULTS: Overall, 14·1% of patients (21·8% of patients with lymphoma, 6·7% of patients with MM) were poor mobilizers. Univariate analysis and multivariate analysis revealed an interval from G-CSF administration to PBSC collection exceeding 10 days and peripheral blood mononuclear cells count on the first day of collection were predictive factors for poor mobilization in lymphoma, but not in MM. Among plerixafor-treated patient group, 9 of 11 poor mobilizers who received second-cycle plerixafor mobilization were able to collect higher number of CD34+ cells than that of CD34+ cells during the G-CSF-based first mobilization. All patients who had received initial plerixafor mobilization reached 2·0 × 10(6) CD34+ cells/kg during the four leukaphereses. CONCLUSION: In conventional G-CSF-based mobilization, early PBSC collection after G-CSF administration might enhance CD34+ cell yield. A combination of a new mobilizing agent, plerixafor, would be helpful to harvest sufficient number of CD34+ cells for successful transplantation outcome while reducing the effort of collection procedures in poor mobilizers.


Assuntos
Linfoma/terapia , Mieloma Múltiplo/terapia , Transplante de Células-Tronco de Sangue Periférico , Adolescente , Adulto , Idoso , Antígenos CD34/metabolismo , Benzilaminas , Ciclamos , Feminino , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Mobilização de Células-Tronco Hematopoéticas/estatística & dados numéricos , Compostos Heterocíclicos/uso terapêutico , Humanos , Incidência , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/metabolismo , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Retrospectivos , Fatores de Risco , Transplante Autólogo
6.
Eur J Clin Nutr ; 67(8): 841-7, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23612511

RESUMO

BACKGROUND/OBJECTIVES: Light-to-moderate alcohol consumption has been proposed to raise serum adiponectin levels, but this view is controversial. There is little information on the effect of heavy drinking. The aim of this study was to examine the relationship between alcohol consumption and serum adiponectin levels in healthy Koreans. SUBJECTS/METHODS: The design of the study was cross-sectional, using data from the Korean Multi-Rural Communities Cohort Study (MRCohort), which is a part of the Korean Genome Epidemiology Study (KoGES). The subjects were 1542 individuals (635 men and 907 women) aged ≥ 40 years who were recruited in Yangpyeong-Gun, Kyunggi province, South Korea, in 2005 and 2006. Daily alcohol consumption was calculated from average frequency of alcohol consumption and the amount of alcohol consumed per occasion using a structured questionnaire and serum adiponectin levels were measured. RESULTS: Although adiponectin levels appeared to be higher in those consuming moderate levels of alcohol than in nondrinkers, the difference was not statistically significant. Heavy drinking (≥ 90.0 g/day) was significantly related to reduced serum adiponectin levels (P=0.003), although the significance of the relationship was reduced after adjusting for potential confounders (P=0.061) such as age, waist/hip ratio, blood pressure, fasting blood glucose, current smoker, higher education, protein intake, vitamin C intake and vitamin E intake in men. The relation seemed to be stronger in individuals consuming alcohol in the form of takju (Korean rice wine; P=0.022). CONCLUSIONS: Heavy alcohol drinking (≥ 90.0 g/day) may be related to lower serum adiponectin levels in Korean men.


Assuntos
Adiponectina/sangue , Consumo de Bebidas Alcoólicas , Etanol/farmacologia , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oryza , República da Coreia , População Rural , Inquéritos e Questionários , Vinho
7.
Clin Lab ; 57(11-12): 959-67, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22239028

RESUMO

BACKGROUND: Human enteroviruses (HEVs) are a major cause of herpangina, HFMD (hand, foot, and mouth disease), and other neurological diseases in Seoul, Korea. METHODS: A total of 56 specimens from hospitalized patients collected from February to December 2009 (37 females and 19 males) in Seoul were tested for HEV from stool, throat swab, and vesicle swab samples taken from patients with herpangina or HFMD using cell culture and RT-PCR in 2009. By the 1D gene, encoding the VP1 capsid protein, seven different HEV genotypes were detected with Coxsackievirus A2, A4, A5, A9, A16 (CA), Coxsackievirus B1 (CB), and Enterovirus 71 (EV71). The most prevalent genotype was CA16 (6, 10.7%), followed by CA2 (4, 7.1%), CA5 (4, 7.1%), EV71 (2, 3.6%), CA4 (1, 1.8%), CA9 (1, 1.8%), and CB1 (1, 1.8%). The 1D gene sequences of two EV71 strains were closely related with one another (98.5% nucleotide similarity) and belonged to the C4 genotype. CONCLUSIONS: It is important to continuously survey the genetic characteristics of EV71 and CA16 from patients, which will provide useful data that aids in our understanding of HFMD infections in Seoul, Korea and may contribute to future control.


Assuntos
Infecções por Coxsackievirus/virologia , Surtos de Doenças , Infecções por Enterovirus/virologia , Enterovirus/isolamento & purificação , Doença de Mão, Pé e Boca/virologia , Herpangina/virologia , Proteínas do Capsídeo/genética , Pré-Escolar , Infecções por Coxsackievirus/epidemiologia , Enterovirus/genética , Enterovirus Humano A/genética , Enterovirus Humano A/isolamento & purificação , Enterovirus Humano B/genética , Enterovirus Humano B/isolamento & purificação , Infecções por Enterovirus/epidemiologia , Fezes/virologia , Feminino , Doença de Mão, Pé e Boca/epidemiologia , Herpangina/epidemiologia , Humanos , Lactente , Recém-Nascido , Masculino , Faringe/virologia , Filogenia , RNA Viral/genética , RNA Viral/isolamento & purificação , República da Coreia/epidemiologia , Análise de Sequência de RNA
8.
Cell Mol Life Sci ; 66(10): 1766-81, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19347570

RESUMO

Indenone KR-62776 acts as an agonist of PPAR gamma without inducing obesity in animal models and cells. X-ray crystallography reveals that the indenone occupies the binding pocket in a different manner than rosiglitazone. 2-Dimensional gel-electrophoresis showed that the expression of 42 proteins was altered more than 2.0-fold between KR-62776- or rosiglitazone-treated adipocyte cells and control cells. Rosiglitazone down-regulated the expression of ERK1/2 and suppressed the phosphorylation of ERK1/2 in these cells. However, the expression of ERK1/2 was up-regulated in KR-62776-treated cells. Phosphorylated ERK1/2, activated by indenone, affects the localization of PPAR gamma, suggesting a mechanism for indenone-inhibition of adipogenesis in 3T3-L1 preadipocyte cells. The preadipocyte cells are treated with ERK1/2 inhibitor PD98059, a large amount of the cells are converted to adipocyte cells. These results support the conclusion that the localization of PPAR gamma is one of the key factors explaining the biological responses of the ligands.


Assuntos
Adipócitos/citologia , Diferenciação Celular/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Indanos/farmacologia , Oximas/farmacologia , PPAR gama/metabolismo , Células 3T3-L1 , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Animais , Cristalografia por Raios X , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , MAP Quinases Reguladas por Sinal Extracelular/genética , Regulação da Expressão Gênica , Indanos/química , Indanos/metabolismo , Camundongos , Modelos Moleculares , Estrutura Molecular , Oximas/química , Oximas/metabolismo , PPAR gama/agonistas , PPAR gama/química , Ligação Proteica , Estrutura Terciária de Proteína , Proteoma/análise , Proteoma/efeitos dos fármacos , Rosiglitazona , Tiazolidinedionas/química , Tiazolidinedionas/metabolismo , Tiazolidinedionas/farmacologia
9.
Arch Virol ; 147(9): 1711-20, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12209311

RESUMO

We have evaluated PCR-RFLP as a practical method for rapid typing of enteroviruses causing aseptic meningitis in Korea. Through blind examination of 80 clinical isolates from patients with aseptic meningitis, we have compared the results of conventional serotyping with PCR-RFLP based genotyping, which was developed for this study. Among the 80 case isolates, which had been previously typed by routine neutralization test, only 42 cases (52.5%) were matched with typing by PCR-RFLP. The result clearly demonstrated that the enterovirus serotype does not coincide with the genotype. Therefore, the classification of enteroviruses by genotyping with PCR-RFLP, although rapid and simple, may be complicated by regional or seasonal differences. However, the PCR-RFLP method developed in this study is applicable to the epidemiological study of enteroviruses when regional or seasonal differences exist, and is useful in identifying the source of an infection.


Assuntos
Enterovirus/classificação , Meningite Asséptica/virologia , Enterovirus/genética , Enterovirus/imunologia , Genótipo , Humanos , Testes de Neutralização , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Sorotipagem
11.
Mol Biol Cell ; 12(9): 2835-45, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11553721

RESUMO

Calreticulin (CRT), a Ca(2+)-binding protein known to have many cellular functions, including regulation of Ca(2+) homoeostasis and chaperone activity, is essential for heart and brain development during embryogenesis in mice. Here, we report the functional characterization of Caenorhabditis elegans calreticulin (crt-1). A crt-1 null mutant does not result in embryonic lethality but shows temperature-dependent reproduction defects. In C. elegans CRT-1 is expressed in the intestine, pharynx, body-wall muscles, head neurons, coelomocytes, and in sperm. crt-1 males exhibit reduced mating efficiency and defects late in sperm development in addition to defects in oocyte development and/or somatic gonad function in hermaphrodites. Furthermore, crt-1 and itr-1 (inositol triphosphate receptor) together are required for normal behavioral rhythms. crt-1 transcript level is elevated under stress conditions, suggesting that CRT-1 may be important for stress-induced chaperoning function in C. elegans.


Assuntos
Caenorhabditis elegans/fisiologia , Proteínas de Ligação ao Cálcio/metabolismo , Cálcio/metabolismo , Chaperonas Moleculares/metabolismo , Ribonucleoproteínas/metabolismo , Animais , Northern Blotting , Western Blotting , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Canais de Cálcio/metabolismo , Proteínas de Ligação ao Cálcio/genética , Calreticulina , Fertilidade/genética , Deleção de Genes , Perfilação da Expressão Gênica , Homeostase , Imuno-Histoquímica , Hibridização In Situ , Receptores de Inositol 1,4,5-Trifosfato , Mucosa Intestinal/metabolismo , Masculino , Chaperonas Moleculares/genética , Músculos/metabolismo , Faringe/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Ribonucleoproteínas/genética , Espermatozoides/metabolismo , Temperatura
12.
Am J Physiol Lung Cell Mol Physiol ; 281(4): L904-12, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11557594

RESUMO

Nitric oxide (NO) fluxes released from the surface of individual activated macrophages or cells localized in small aggregates were measured with a novel polarographic self-referencing microsensor. NO fluxes could be detected at distances from the cells of 100-500 microm. The initial flux and the distance from the cells at which NO could be detected were directly related to the number of cells in the immediate vicinity of the probe releasing NO. Thus, whereas NO fluxes of approximately 1 pmol. cm(-2). s(-1) were measured from individual macrophages, aggregates composed of groups of cells varying in number from 18 to 48 cells produced NO fluxes of between approximately 4 and 10 pmol. cm(-2). s(-1). NO fluxes required the presence of L-arginine. Signals were significantly reduced by the addition of hemoglobin and by N-nitro-L-arginine methyl ester. NO fluxes were greatest when the sensor was placed immediately adjacent to cell membranes and declined as the distance from the cell increased. The NO signal was markedly reduced in the presence of the protein albumin but not by either oxidized or reduced glutathione. A reduction in the NO signal was also noted after the addition of lipid micelles to the culture medium. These results demonstrate that NO can be detected at significant distances from the cell of origin. In addition, both proteins and lipids strongly influence the net movement of free NO from macrophages. This suggests that these tissue components play an important role in regulating the biological activity of NO.


Assuntos
Metabolismo dos Lipídeos , Macrófagos Alveolares/metabolismo , Proteínas de Membrana/metabolismo , Óxido Nítrico/metabolismo , Animais , Arginina/farmacologia , Calibragem , Linhagem Celular , Difusão , Inibidores Enzimáticos/farmacologia , Glutationa/farmacologia , Macrófagos Alveolares/citologia , Micelas , Microeletrodos , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Soroalbumina Bovina/farmacologia
13.
Anal Chem ; 73(15): 3759-67, 2001 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-11510845

RESUMO

Glucose gradients generated by an artificial source and beta-cells were measured using an enzyme-based glucose microsensor, 8-microm tip diameter, as a self-referencing electrode. The technique is based on a difference measurement between two locations in a gradient and thus allows us to obtain real-time flux values with minimal impact of sensor drift or noise. Flux values were derived by incorporation of the measured differential current into Fick's first equation. In an artificial glucose gradient, a flux detection limit of 8.2 +/- 0.4 pmol.cm(-2).s(-1) (mean +/- SEM, n = 7) with a sensor sensitivity of 7.0 +/- 0.4 pA/ mM (mean +/- SEM, n = 16) was demonstrated. Under biological conditions, the glucose sensor showed no oxygen dependence with 5 mM glucose in the bulk medium. The addition of catalase to the bulk medium was shown to ameliorate surface-dependent flux distortion close to specimens, suggesting an underlying local accumulation of hydrogen peroxide. Glucose flux from beta-cell clusters, measured in the presence of 5 mM glucose, was 61.7 +/- 9.5 fmol.nL(-1).s(-1) (mean +/- SEM, n = 9) and could be pharmacologically modulated. Glucose consumption in response to FCCP (1 microM) transiently increased, subsequently decreasing to below basal by 93 +/- 16 and 56 +/- 6%, respectively (mean +/- SEM, n = 5). Consumption was decreased after the application of 10 microM rotenone by 74 +/- 5% (mean +/- SEM, n = 4). These results demonstrate that an enzyme-based amperometric microsensor can be applied in the self-referencing mode. Further, in obtaining glucose flux measurements from small clusters of cells, these are the first recordings of the real-time dynamic of glucose movements in a biological microenvironment.


Assuntos
Técnicas Biossensoriais , Enzimas Imobilizadas/análise , Glucose/metabolismo , Ilhotas Pancreáticas/metabolismo , Carbonil Cianeto p-Trifluormetoxifenil Hidrazona/farmacologia , Células Cultivadas , Eletrodos , Enzimas Imobilizadas/metabolismo , Glucose/agonistas , Glucose/antagonistas & inibidores , Glucose Oxidase/metabolismo , Humanos , Ilhotas Pancreáticas/efeitos dos fármacos , Padrões de Referência , Rotenona/farmacologia
14.
Cell Death Differ ; 8(3): 298-307, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11319613

RESUMO

AIP (apoptosis-inducing protein) is a protein purified and cloned from Chub mackerel infected with the larval nematode, Anisakis simplex, which induces apoptosis in various mammalian cells including human tumor cell lines. AIP has shown structural and functional homology to L-amino acid oxidase (LAO) which oxidizes several L-amino acids including L-lysine and AIP-induced apoptosis has been suggested to be mediated by H2O2 generated by LAO activity of AIP. In this study, we confirmed that recombinant AIP generated enough H2O2 in culture medium to induce rapid apoptosis in cells and this apoptosis was clearly inhibited by co-cultivation with antioxidants such as catalase and N-acetyl-cysteine. Surprisingly, however, we found that AIP still could induce H2O2-independent apoptosis more slowly than H2O2-dependent one in HL-60 cells even in the presence of antioxidants. In addition, the HL-60-derived cell line HP100-1, which is a H2O2-resistant variant, underwent apoptosis on treatment with AIP with a similar delayed time course. The latter apoptosis was completely blocked by addition of L-lysine to the culture medium, which is the best substrate of AIP as LAO, indicating that decreased concentration of L-lysine in the culture medium by AIP-treatment induced apoptosis. We also showed that the both apoptosis by AIP were associated with the release of cytochrome c from mitochondria and activation of caspase-9, and overexpressed Bcl-2 could inhibit both of the AIP-induced apoptosis. These results indicate that AIP induces apoptosis in cells by two distinct mechanisms; one rapid and mediated by H2O2, the other delayed and mediated by deprivation of L-lysine, both of which utilize caspase-9/cytochrome c system.


Assuntos
Anisaquíase/metabolismo , Proteínas Reguladoras de Apoptose/farmacologia , Apoptose/efeitos dos fármacos , Doenças dos Peixes/metabolismo , Perciformes/metabolismo , Animais , Anisaquíase/parasitologia , Anisaquíase/veterinária , Anisakis/fisiologia , Apoptose/fisiologia , Proteínas Reguladoras de Apoptose/biossíntese , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/isolamento & purificação , Western Blotting , Caspase 3 , Caspase 9 , Caspases/metabolismo , Linhagem Celular Tumoral , Citocromos c/metabolismo , Ativação Enzimática , Doenças dos Peixes/parasitologia , Doenças dos Peixes/patologia , Células HL-60 , Humanos , Peróxido de Hidrogênio/metabolismo , Lisina/deficiência , Lisina/metabolismo , Mitocôndrias/metabolismo , Perciformes/parasitologia , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Proteínas Proto-Oncogênicas c-bcl-2/fisiologia , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/farmacologia
16.
J Immunol ; 165(3): 1491-7, 2000 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-10903755

RESUMO

While investigating the effect of marine products on cell growth, we found that visceral extracts of Chub mackerel, an ocean fish, had a powerful and dose-dependent apoptosis-inducing effect on a variety of mammalian tumor cells. This activity was strikingly dependent on infection of the C. mackerel with the larval nematode, Anisakis simplex. After purification of the protein responsible for the apoptosis-inducing activity, we cloned the corresponding gene and found it to be a flavoprotein. This protein, termed apoptosis-inducing protein (AIP), was also found to possess an endoplasmic reticulum retention signal (C-terminal KDEL sequence) and H2O2-producing activity, indicating that we had isolated a novel reticuloplasimin with potent apoptosis-inducing activity. AIP was induced in fish only after infection with larval nematode and was localized to capsules that formed around larvae to prevent their migration to host tissues. Our results suggest that AIP may function to impede nematode infection.


Assuntos
Anisaquíase/imunologia , Anisakis/imunologia , Apoptose/imunologia , Peixes/imunologia , Flavoproteínas/genética , Flavoproteínas/isolamento & purificação , Proteínas de Membrana/genética , Proteínas de Membrana/isolamento & purificação , Células 3T3 , Sequência de Aminoácidos , Animais , Anisaquíase/parasitologia , Anisakis/genética , Anisakis/metabolismo , Anisakis/patogenicidade , Fator de Indução de Apoptose , Cálcio/metabolismo , Clonagem Molecular , Retículo Endoplasmático/fisiologia , Fibrinolisina/fisiologia , Peixes/parasitologia , Flavoproteínas/imunologia , Flavoproteínas/metabolismo , Células HL-60 , Humanos , Peróxido de Hidrogênio/metabolismo , Larva/genética , Larva/imunologia , Larva/metabolismo , Larva/patogenicidade , Proteínas de Membrana/imunologia , Proteínas de Membrana/metabolismo , Camundongos , Dados de Sequência Molecular
17.
J Biol Chem ; 275(9): 6642-50, 2000 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-10692473

RESUMO

Micron-sized sensors were used to monitor glucose and oxygen levels in the extracellular space of single islets of Langerhans in real-time. At 10 mM glucose, oscillations in intraislet glucose concentration were readily detected. Changes in glucose level correspond to changes in glucose consumption by glycolysis balanced by mass transport into the islet. Oscillations had a period of 3.1 +/- 0.2 min and amplitude of 0.8 +/- 0.1 mM glucose (n = 21). Superimposed on these oscillations were faster fluctuations in glucose level during the periods of low glucose consumption. Oxygen level oscillations that were out of phase with the glucose oscillations were also detected. Oscillations in both oxygen and glucose consumption were strongly dependent upon extracellular Ca(2+) and sensitive to nifedipine. Simultaneous measurements of glucose with intracellular Ca(2+) ([Ca(2+)](i)) revealed that decreases in [Ca(2+)](i) preceded increases in glucose consumption by 7.4 +/- 2.1 s during an oscillation (n = 9). Conversely, increases in [Ca(2+)](i) preceded increases in oxygen consumption by 1.5 +/- 0.2 s (n = 4). These results suggest that during oscillations, bursts of glycolysis begin after Ca(2+) has stopped entering the cell. Glycolysis stimulates further Ca(2+) entry, which in turn stimulates increases in respiration. The data during oscillation are in contrast to the time course of events during initial exposure to glucose. Under these conditions, a burst of oxygen consumption precedes the initial rise in [Ca(2+)](i). A model to explain these results is described.


Assuntos
Cálcio/metabolismo , Glucose/metabolismo , Ilhotas Pancreáticas/metabolismo , Consumo de Oxigênio , Animais , Técnicas Biossensoriais , Respiração Celular , Glicólise , Camundongos , Microeletrodos , Modelos Biológicos , Nifedipino/farmacologia
18.
Anal Chem ; 71(17): 3642-9, 1999 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-10489519

RESUMO

An oxygen microsensor with a < 3-micron tip diameter was developed for monitoring oxygen levels at single cells and mouse pancreatic islets. The sensor was fabricated by electrochemically recessing an etched Pt wire inside a pulled glass micropipet and then coating with cellulose acetate. This fabrication process was found to be simpler than previous oxygen electrode designs of comparable size. The microsensors had a average sensitivity of 0.59 +/- 0.29 pA/mmHg (mean +/- SD, n = 42), signals that were minimally perturbed by convection, and response times of < 1 s. The electrode was used to measure the oxygen gradient around and inside single mouse islets. The measurements demonstrate that oxygen levels within even the largest islets at maximal glucose stimulation are 67 +/- 1.6 mmHg (mean +/- SD, n = 5), indicating that islets have adequate oxygen supplies by diffusion under tissue culture conditions to support insulin secretion. The electrode was also used to record the dynamics of oxygen level at single islets as a function of glucose concentration. As glucose level was changed from 3 to 10 mM, oxygen level decreased by 15.8 +/- 2.3 mmHg (mean +/- SEM, n = 6) and oscillations with a period of 3.3 +/- 0.6 min (mean +/- SEM, n = 6) appeared in the oxygen level. In islets bathed in quiescent solutions containing 10 mM glucose, similar oscillations could be observed. In addition, in the quiet solutions it was possible to detect faster oscillations with a period of 12.1 +/- 1.7 s (mean +/- SEM, n = 6) superimposed on the slower oscillations. Oxygen consumption could also be observed at single insulinoma cells using the electrode. Individual cells also showed oscillations in oxygen consumption with a period of a few seconds. The results demonstrate that the electrode can be used for dynamic oxygen level recordings in biological microenvironments.


Assuntos
Técnicas Biossensoriais , Ilhotas Pancreáticas/química , Oxigênio/análise , Animais , Camundongos , Microeletrodos
19.
Biochem Biophys Res Commun ; 259(2): 331-5, 1999 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-10362508

RESUMO

A novel oxygen microsensor was used to measure oxygen levels in single mouse islets as a function of glucose concentration. Oxygen consumption of individual islets was 5.99 +/- 1.17, 9.21 +/- 2.15, and 12.22 +/- 2.16 pmol/min at 3, 10, and 20 mM glucose, respectively (mean +/- SEM, n = 10). Consumption of oxygen was islet-size dependent as larger islets consumed more oxygen than smaller islets but smaller islets consumed more oxygen per unit volume than larger islets. Elevating glucose levels from 3 to 10 mM induced pronounced fast oscillations in oxygen level (period of 12.1 +/- 1.7 s, n = 6) superimposed on top of large slow oscillations (period of 3.3 +/- 0.6 min, n = 6). The fast oscillations could be completely abolished by treatment with the L-type Ca2+-channel blocker nifedipine (40 microM) with a lesser effect on slow oscillations. Slow oscillations were almost completely dependent upon extracellular Ca2+. The oxygen patterns closely mimic those that have previously been reported for intracellular Ca2+ levels and are suggestive of an important role for Ca2+ in amplifying metabolic oscillations.


Assuntos
Ilhotas Pancreáticas/metabolismo , Consumo de Oxigênio , Animais , Técnicas Biossensoriais , Cálcio/farmacologia , Bloqueadores dos Canais de Cálcio/farmacologia , Respiração Celular/efeitos dos fármacos , Glucose/metabolismo , Camundongos , Nifedipino/farmacologia , Oxigênio/análise
20.
Br J Dermatol ; 139(5): 885-8, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9892960

RESUMO

In adults, cellulitis is usually caused by group A streptococci and Staphylococcus aureus. However, in patients with underlying disease, it may be caused by other organisms, such as Acinetobacter, Clostridium septicum, Enterobacter, Haemophilus influenzae, Proteus mirabilis or Escherichia coli. We report three cases of cellulitis of the lower legs where E. coli was the causative bacterial organism. It is important to suspect E. coli as a causative organism if blistering cellulitis occurs, especially in patients with underlying diseases.


Assuntos
Celulite (Flegmão)/microbiologia , Infecções por Escherichia coli/imunologia , Hospedeiro Imunocomprometido , Infecções Oportunistas/imunologia , Celulite (Flegmão)/imunologia , Humanos , Dermatoses da Perna/imunologia , Dermatoses da Perna/microbiologia , Masculino , Pessoa de Meia-Idade
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