Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 25
Filtrar
1.
J Eur Acad Dermatol Venereol ; 32(6): 999-1003, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28940547

RESUMO

BACKGROUND: The epidemiology of Adamantiades-Behçet's disease varies among ethnic populations worldwide. Trends in the incidence of Adamantiades-Behçet's disease have not been investigated based on the Korean National Health Insurance database. OBJECTIVES: This study investigated the incidence and mortality of Adamantiades-Behçet's disease by age using nationwide population data in Korea. METHODS: A nationwide population-based cohort study was performed using the Korean National Health Insurance Claims Database from 2006 to 2015. The incidence of Adamantiades-Behçet's disease was calculated by age, sex, calendar year and habitat. And comorbid metabolic diseases were also analysed in patients with Adamantiades-Behçet's disease. RESULTS: The annual incidence of Adamantiades-Behçet's disease per 100 000 person-years was 3.976 (2.587 for males and 5.373 for females) from 2006 to 2015. The incidence of Adamantiades-Behçet's disease peaked among people in their 40s (6.561 per 100 000 person-years). Incidence was significantly higher in subjects with comorbid metabolic conditions, such as diabetes mellitus, hypertension and dyslipidemia. The mortality rate per 1000 person-years increased with age in patients with Adamantiades-Behçet's disease. CONCLUSIONS: This study showed the incidence, prevalence and mortality of Adamantiades-Behçet's disease. Metabolic conditions increased the risk of Adamantiades-Behçet's disease among Koreans.


Assuntos
Síndrome de Behçet/epidemiologia , Vigilância da População , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Síndrome de Behçet/mortalidade , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Prevalência , República da Coreia/epidemiologia , Adulto Jovem
2.
Eur Rev Med Pharmacol Sci ; 16(7): 853-9, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22953631

RESUMO

BACKGROUND AND OBJECTIVES: Methicillin-resistant Staphylococcus aureus (MRSA) infections are a rapidly growing health problem around the globe. Recently, there has been considerable interest in the use of plant materials as an alternative method to control pathogenic microorganisms. In this study we evaluated the antibacterial activity of bark of Alnus pendula against MRSA. MATERIALS AND METHODS: The MIC determination was done using the microdilution broth method and bacterial growth was determined by measuring optical density using spectrophotometer. RESULTS: Alnus pendula bark EtOH extract and fractions (F-1, -2, -3 and -4) were investigated against MRSA. The most active fractions (F-3 and F-4) led to the isolation of oregonin (ORE) and hirsutanone (HIR). These compounds were active against MRSA strains with minimum inhibitory concentrations (MICs) ranging from 31.25 to 250 microg/ml MIC and 2 MIC of HIR completely inhibited the growth of MRSA. CONCLUSIONS: The bark EtOH extract of Alnus Pendula has potent antibacterial activity against MRSA.


Assuntos
Alnus , Antibacterianos/farmacologia , Resistência a Meticilina , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Extratos Vegetais/farmacologia , Alnus/química , Antibacterianos/química , Antibacterianos/isolamento & purificação , Diarileptanoides/farmacologia , Etanol/química , Staphylococcus aureus Resistente à Meticilina/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Casca de Planta , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Plantas Medicinais , Solventes/química , Espectrofotometria
3.
Eur Rev Med Pharmacol Sci ; 16 Suppl 3: 121-5, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22957426

RESUMO

BACKGROUND AND OBJECTIVES: Papaveraceae serve as a rich source of various alkaloids which have anti-inflammatory effect. MATERIALS AND METHODS: In this study, we investigated the effect of Hylomecon hylomeconoides ethanol extract (HHE) on lipopolysaccharide (LPS)-induced NO and interleukin-6 (IL-6) production in RAW 264.7 cells. RESULTS: HHE inhibited LPS-induced NO and IL-6 production. Moreover, HHE suppressed the phosphorylation of ERK1/2 and p38 in LPS-induced RAW 264.7 in a dose-dependent manner. Furthermore, major constituents, dihydrosanguinarine and 6-methoxydihydrosanguinarine, of the chloroform-soluble extract were analyzed. CONCLUSIONS: Taken together, the results of this study indicate that the anti-inflammatory effects of HHE may occur via the inhibition of NO and IL-6 expression through the down-regulation of MAP kinase (ERK1/2, p38) phosphorylation in RAW 264.7 cells.


Assuntos
Anti-Inflamatórios/farmacologia , Inflamação/tratamento farmacológico , Papaveraceae/química , Extratos Vegetais/farmacologia , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/isolamento & purificação , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Inflamação/fisiopatologia , Interleucina-6/metabolismo , Lipopolissacarídeos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Camundongos , Óxido Nítrico/metabolismo , Fosforilação/efeitos dos fármacos , Extratos Vegetais/administração & dosagem
4.
Poult Sci ; 91(8): 1983-9, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22802194

RESUMO

Isolation and identification of Cryptococcus neoformans and pathogenic yeast-like fungi from pigeon droppings has been taken for a long time and requires various nutrients for its growth. In this study, we attempted to establish a rapid direct identification method of Cr. neoformans from pigeon dropping samples by nested-PCR using internal transcribed spacer (ITS) CAP64 and CNLAC1 genes, polysaccharide capsule gene and laccase-associated gene to produce melanin pigment, respectively, which are common genes of yeasts. The ITS and CAP64 genes were amplified in all pathogenic yeasts, but CNLAC1 was amplified only in Cr. neoformans. The ITS gene was useful for yeast genotyping depending on nucleotide sequence. Homology of CAP64 genes among the yeasts were very high. The specificity of PCR using CNLAC1 was demonstrated in Cr. neoformans environmental strains but not in other yeast-like fungi. The CNLAC1 gene was detected in 5 serotypes of Cr. neoformans. The nested-PCR amplified up to 10(-11) µg of the genomic DNA and showed high sensitivity. All pigeon droppings among 31 Cr. neoformans-positive samples were positive and all pigeon droppings among 348 Cr. neoformans-negative samples were negative by the direct nested-PCR. In addition, after primary enrichment of pigeon droppings in Sabouraud dextrose broth, all Cr. neoformans-negative samples were negative by the nested-PCR, which showed high specificity. The nested-PCR showed high sensitivity without culture of pigeon droppings. Nested-PCR using CNLAC1 provides a rapid and reliable molecular diagnostic method to overcome weak points such as long culture time of many conventional methods.


Assuntos
Columbidae/microbiologia , Criptococose/veterinária , Cryptococcus neoformans/isolamento & purificação , Fezes/microbiologia , Proteínas Fúngicas/metabolismo , Reação em Cadeia da Polimerase/veterinária , Animais , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica/fisiologia
5.
Avian Dis ; 56(1): 58-64, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22545529

RESUMO

Cryptococcus neoformans (C neoformans) is a frequent cause of invasive fungal disease in immunocompromised human hosts. Ninety-eight samples of pigeon droppings were collected from the pigeon shelters in Seoul, and cultured on birdseed agar (BSA) and Sabouraud dextrose agar (SDA). One hundred yeast-like colonies were selected and identified via phenotype characteristics, such as colony morphology and biochemical characteristics. This was then followed with genotyping via sequencing of the internal transcribed spacer (ITS) region. The colonies were classified into four kinds of colony color types: brown type (BrT), beige type (BeT), pink type (PT), and white type (WT). Numbers of isolated BrT, BeT, PT, and WT colonies were 22 (22%), 30 (30%), 19 (19%), and 39 (39%), respectively. All BrT colonies were identified as C neoformans. BeT were identified as 19 isolates of Cryptococcus laurentii, 10 isolates of Malassezia furfur, and 1 isolate of Cryptococcus uniguttulatus. PT was divided into two colony color types: light-PT (l-PT) and deep-PT (d-PT). Eighteen of l-PT and one of d-PT were identified as Rhodotorula glutinis and Rhodotorula mucilaginosa, respectively. WT were identified as 34 isolates of Cryptococcus guilliermondii, 3 isolates of Cryptococcus zeylanoides, 1 isolate of Cryptococcus sake, and 1 isolate of Stephanoascus ciferrii. Most strains were classified identically with the use of either phenotype or genotyping techniques, but C uniguttulatus and C sake classified by phenotyping were Pseudozyma aphidis and Cryptococcus famata by genotyping. This rapid screening technique of pathogenic yeast-like fungi by only colony characteristics is also expected to be very useful for primary yeast screening. Additionally, we investigated the seasonal variations of C neoformans and other yeast-like fungi from 379 pigeon-dropping samples that were collected from February 2011 to March 2011. We isolated 685 yeast-like fungi from the samples. Almost all C neoformans and yeast-like fungi were isolated in the fall (298 strains, 43.5%) and spring (244 strains, 35.6%). A few yeast-like fungi were isolated in winter (98 strains, 14.3%) and summer (45 strains, 6%). These results would be used as an important indicator related to epidemiology and prevention of pathogenic yeast-like fungi infections transmitted through pigeon droppings.


Assuntos
Columbidae/microbiologia , Cryptococcus neoformans/isolamento & purificação , DNA Espaçador Ribossômico/genética , Fezes/microbiologia , Leveduras/isolamento & purificação , Animais , Contagem de Colônia Microbiana/veterinária , Cryptococcus neoformans/classificação , Genótipo , Reação em Cadeia da Polimerase , República da Coreia , Estações do Ano , Análise de Sequência de DNA , Leveduras/classificação
6.
Poult Sci ; 91(2): 275-81, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22252338

RESUMO

A geothermal heat pump (GHP) is a potential heat source for the economic heating of broiler houses with optimum production performance. An investigation was conducted to evaluate the effect of a heating system using a GHP on production performance and housing environment of broiler chickens. A comparative analysis was also performed between the GHP system and a conventional heating system that used diesel for fuel. In total, 34,000 one-day-old straight run broiler chicks were assigned to 2 broiler houses with 5 replicates in each (3,400 birds/replicate pen) for 35 d. Oxygen(,) CO(2), and NH(3) concentrations in the broiler house, energy consumption and cost of heating, and production performance of broilers were evaluated. Results showed that the final BW gain significantly (P < 0.05) increased when chicks were reared in the GHP broiler house compared with that of chicks reared in the conventional broiler house (1.73 vs. 1.62 kg/bird). The heating system did not affect the mortality of chicks during the first 4 wk of the experimental period, but the mortality markedly increased in the conventional broiler house during the last wk of the experiment. Oxygen content in the broiler house during the experimental period was not affected by the heating system, but the CO(2) and NH(3) contents significantly increased (P < 0.05) in the conventional broiler house compared with those in the GHP house. Fuel consumption was significantly reduced (P < 0.05) and electricity consumption significantly increased (P < 0.05) in the GHP house compared with the consumption in the conventional house during the experiment. The total energy cost of heating the GHP house was significantly lower (P < 0.05) compared with that of the conventional house. It is concluded that a GHP system could increase the production performance of broiler chicks due to increased inside air quality of the broiler house. The GHP system had lower CO(2) and NH(3) emissions with lower energy cost than the conventional heating system for broiler chickens.


Assuntos
Galinhas/crescimento & desenvolvimento , Energia Geotérmica , Abrigo para Animais , Amônia , Animais , Dióxido de Carbono , Feminino , Gasolina , Abrigo para Animais/economia , Masculino , Oxigênio
7.
Lett Appl Microbiol ; 52(4): 367-71, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21251028

RESUMO

AIMS: Studies of pigeon-borne yeasts have tended to focus on species, such as Cryptococcus neoformans and Candida albicans, with scant attention to feral pigeons in Korea. We studied the prevalence of yeasts from faecal samples of feral pigeons obtained in various public places in Seoul, Korea, and assessed their potential capacity as human pathogens. METHODS AND RESULTS: Three hundred and six pigeon faeces samples were collected at city squares and parks in 21 localities in Seoul and Seoul Grand Park and analysed for yeast with conventional methods. Of the 306 samples, 126 (41·2%) were positive for yeast. Seventeen species of yeast were identified. The most frequent species were Candida glabrata (34·1%), Candida famata (12·7%), Cryptococcus albidus (14·3%) and Cryptococcus laurentii (7·9%). The yeast isolates were tested for virulence. Of the 116 isolates (ten isolates missing), 70·7% (n = 82) grew at 37°C. All the Cryptococcus spp. isolates possessed a capsule, 16·4% (n = 19) produced melanin, and 33·6% (n = 39) produced proteinase. Two Ca. glabrata, a Ca. famata and Ca. albicans as well as three C. neoformans, a C. laurentii and Ca. albicans isolates had three virulence factors. Accordingly, 29·3% (n = 34) isolates possessed more than two virulence factors except capsule formation. CONCLUSIONS: These results of this study indicate that feral pigeons harbour a variety of yeasts and are a reservoir of human pathogenic fungi. SIGNIFICANCE AND IMPACT OF THE STUDY: This study is the first time about the microflora (fungi) presents in faecal samples collected from a variety of public areas throughout Seoul, Korea.


Assuntos
Columbidae/microbiologia , Leveduras/isolamento & purificação , Leveduras/patogenicidade , Animais , Candida/isolamento & purificação , Candida/patogenicidade , Candida albicans/isolamento & purificação , Candida albicans/patogenicidade , Cryptococcus/isolamento & purificação , Cryptococcus/patogenicidade , Fezes/microbiologia , Humanos , Coreia (Geográfico) , Fatores de Virulência/metabolismo , Leveduras/crescimento & desenvolvimento
9.
Eur Rev Med Pharmacol Sci ; 14(12): 1005-9, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21375130

RESUMO

BACKGROUND AND OBJECTIVES: Methicillin-resistant Staphylococcus aureus (MRSA) has been a serious problem as its infection is associated with higher mortality and increase cost worldwide. In the present study, the antibacterial activity of enhydrin, polymatin B, allo-schkuhriolide from the leaves of Smallanthus sonchifolius was investigated. MATERIAL AND METHODS: Enhydrin, polymatin B, allo-schkuhriolide from the leaves of Smallanthus sonchifolius were tested for antimicrobial activity using micro dilution broth method against 2 strains of ATCC 33591, ATCC 25923 and 15 strains of clinical isolates MRSA. RESULTS: The antibacterial activity of Smallanthus sonchifolius can safely be attributed to enhydrin as polymatin B, and allo-schkuhriolide are not showing any activity against Staphylococcus aureus strains. The enhydrin showed good antibacterial activity against all tested strains (MIC = 125-500 microg/ml). DISCUSSION: These results suggest that only enhydrin can be considered as an antibacterial drug against MRSA.


Assuntos
Antibacterianos/farmacologia , Asteraceae , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Extratos Vegetais/farmacologia , Sesquiterpenos/farmacologia , Proteínas de Bactérias/genética , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Proteínas de Ligação às Penicilinas , Folhas de Planta , Reação em Cadeia da Polimerase
11.
J Vet Med A Physiol Pathol Clin Med ; 54(4): 210-8, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17493168

RESUMO

Insulin-like growth factor (IGF)-1 has been successfully demonstrated to stimulate proteoglycan synthesis, slow down its catabolism and promote cartilage formation through well defined in vitro studies. It was therefore, assumed that IGF-1 would eventually serve to augment current cartilage repair techniques in vivo. Study was therefore, designed to determine the influence of IGF-1 in cartilage repair with or without autografting. For this purpose articular cartilage repair model was created in the left knee of 48 New Zealand white rabbits of either sex, 6-7 months old, weighing 1-2 kg. The articular cartilage defect was created in the femoral groove of femoro-patellar joint using hand held trephine under xylazine and ketamine anaesthesia in all the animals. The defect created was 3 mm in diameter and 2 mm in depth. For autografting, osteochondral tissues harvested from the proximal patellar groove of the femur were placed in the distal defect and vice versa. The experimental animals were divided mainly into four groups, i.e. Group A (control), Group B (autografting), Group C (control + IGF-1) and Group D (autografting + IGF-1). Animals of group A and B were provided only with collagen scaffolds at 10 mug/cm(2) whereas animals of treatment group C and D were provided with collagen scaffolds holding 30 ng/30 mul of IGF-1 into the defect. Evaluation of cartilage repair was done on days 15, 30 and 45 after ethically killing the animals. Initially IGF-1 had shown the tendency for either in the maintenance of autografted cartilage or helped in proliferation of chondroblast for the repair process. However, later in the process, cartilage formation apparently declined and appeared to converge to osseous tissue. Collectively, non-responsiveness of osteoarthritic chondrocytes to IGF-1 could be partially attributed to either increased IGF-binding proteins in the joint space, micromovement of the graft, lack of nutrition, dose of IGF-1 or its half life in the current study.


Assuntos
Cartilagem Articular/lesões , Cartilagem Articular/metabolismo , Condrócitos/transplante , Fator de Crescimento Insulin-Like I/metabolismo , Transplante Autólogo/veterinária , Animais , Feminino , Masculino , Coelhos , Distribuição Aleatória , Resultado do Tratamento
12.
J Anim Sci ; 85(5): 1126-35, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17178811

RESUMO

Ciglitizone, a class of thiazolidinediones, acts as a potent activator of the adipose differentiation program in established preadipose cell lines. Thiazolidinediones have also been investigated in diabetic patients and have been reported to act as peroxisome proliferator-activated receptor-gamma ligands. Intramuscular adipogenesis or marbling through transdifferentiation of satellite cells in cattle was successfully conducted earlier. In this report, the effects of ciglitizone on the differentiation pathway of porcine myogenic satellite cells was investigated. Semitendinosus muscle was aseptically taken from 10-d-old piglets under general anesthesia, and porcine satellite cells were obtained and grown to near confluence. Postconfluent cells (d 0) were further cultured in differentiation medium containing an adipogenic mixture plus ciglitizone (10 microM) for 48 h. From d 2 onward, the cells were cultured only in the presence of ciglitizone until d 10. Controls were cultured in differentiation medium only. Exposure of porcine satellite cells to the adipogenic mixture plus ciglitizone generated lipid droplets on d 2, and subsequently, exposure of cells to ciglitizone alone helped in cytoplasmic lipid filling, providing them with the acquisition of adipocyte morphology. An increase (P < 0.05) in the fusion (structures containing 2 to 3 nuclei) of satellite cells was observed, and myosin heavy chain appeared with greater intensity (immunohistochemistry) in the control group from d 2 onward. Adipocyte-specific transcriptional factors (i.e., CCAAT/enhancer binding protein-alpha and peroxisome proliferator-activated receptor-gamma) were predominant during transdifferentiation and were observed with immunohistochemistry, Western blot (approximately 47.2 and approximately 60.4 kDa, respectively), and real-time PCR. Ciglitizone appeared to convert the differentiation pathway of satellite cells into that of adipoblasts.


Assuntos
Adipócitos/citologia , Diferenciação Celular/efeitos dos fármacos , Células Satélites de Músculo Esquelético/citologia , Células Satélites de Músculo Esquelético/efeitos dos fármacos , Suínos , Tiazolidinedionas/farmacologia , Adipócitos/efeitos dos fármacos , Adipócitos/fisiologia , Animais , Proteína alfa Estimuladora de Ligação a CCAAT/genética , Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo , Células Cultivadas , Regulação da Expressão Gênica/efeitos dos fármacos , PPAR gama/genética , PPAR gama/metabolismo , Células Satélites de Músculo Esquelético/fisiologia
13.
Meat Sci ; 69(3): 583-7, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22063000

RESUMO

This study developed a new equation to predict the carcass yield of Hanwoo cattle, as well as re-evaluating a previous prediction equation. Experimental animals comprised 79 cows, 79 steers, and 79 bulls. A stepwise model selection was performed to determine the most practical carcass traits for predicting the yield. Cold carcass weight (CW), backfat thickness (BFT), and ribeye area (REA) accounted for 52% variation in yield, and these were determined as the final parameters. When the kidney, pelvic, and heart fat were included in the model, this increased the percentage variation explained (R(2)) by 4%. To compare the newly developed equation (Yield=64.65-0.0198×CW-5.2264×BFT+0.1339×REA) and the previously used one, carcass yields of 377,048 industrial animals (145,695 cows, 225,926 bulls, and 5427 steers) were assessed. For the newly developed equation, the mean difference between experimental animals industrial animals differed only by 1.99-2.68% for all sex groups. In the case of the previous prediction equation, the mean difference ranged from 6.06% for bulls to 11.05% for steers. The results demonstrated that the prediction equation should use a mixture of sex and market weight groups. The results also support our decision to use the newly developed model in predicting the yield of Hanwoo.

14.
Dis Esophagus ; 15(4): 330-3, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12472482

RESUMO

The most common type of esophageal food-related foreign body is the meat bolus, which is frequently associated with underlying esophageal stenosis. Herein, we report two cases of meat bolus impaction associated with nutcracker esophagus. In the first case, the 63-year-old male patient had chest discomfort and swallowing difficulty after ingestion of butcher's meat. In the second case, the 55-year-old male patient had complained of swallowing difficulty after ingestion of chicken. In both cases, no pathologic findings were observed endoscopically after removal of the esophageal meat bolus. We performed esophageal manometry, which showed very high amplitudes of esophageal pressure in the mid- and distal esophagus. These findings were consistent with nutcracker esophagus. These cases show that esophageal motility disorder may be the cause of esophageal foreign body impaction, and esophageal manometry should be performed for evaluation of the cause of foreign body, especially in an endoscopically normal patient.


Assuntos
Transtornos de Deglutição/complicações , Esôfago , Corpos Estranhos , Transtornos de Deglutição/fisiopatologia , Esofagoscopia , Corpos Estranhos/diagnóstico , Corpos Estranhos/cirurgia , Humanos , Masculino , Manometria , Carne , Pessoa de Meia-Idade
15.
J Neurosci Res ; 65(5): 403-7, 2001 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-11536323

RESUMO

In the present study, we investigated effects of estrogen on cell death induced by carboxy-terminal fragment of amyloid precursor protein (CT), a candidate causative substance in the pathogenesis of Alzheimer's disease. 17 beta-Estradiol attenuated CT-induced cell death in PC12 cells, whereas 17 alpha-estradiol, nonestrogenic stereoisomer, did not exert any significant protective effect on CT-induced cell death. These results suggest that protective effects of estrogen may be mediated by estrogen receptor (ER) in PC12 cells. To confirm the results, we determined the effects of tamoxifen, an estrogen receptor antagonist. Tamoxifen blocked the protective effects of 17 beta-estradiol, although it did not affect those of 17 alpha-estradiol. Overall, it might be thought that the protective effect of estradiol on CT-induced cell death is achieved by hormonal properties mediated through the estrogen receptor rather than the structural properties as a reducing agent.


Assuntos
Precursor de Proteína beta-Amiloide/metabolismo , Dióxido de Carbono/toxicidade , Morte Celular/efeitos dos fármacos , Estradiol/farmacologia , Fármacos Neuroprotetores/farmacologia , Fragmentos de Peptídeos/toxicidade , Receptores de Estrogênio/metabolismo , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Doença de Alzheimer/fisiopatologia , Animais , Dióxido de Carbono/antagonistas & inibidores , Morte Celular/fisiologia , Antagonistas de Estrogênios/farmacologia , Degeneração Neural/metabolismo , Degeneração Neural/patologia , Degeneração Neural/fisiopatologia , Células PC12/efeitos dos fármacos , Células PC12/metabolismo , Células PC12/patologia , Fragmentos de Peptídeos/antagonistas & inibidores , Estrutura Terciária de Proteína/efeitos dos fármacos , Estrutura Terciária de Proteína/fisiologia , Ratos , Receptores de Estrogênio/efeitos dos fármacos , Tamoxifeno/farmacologia
17.
J Neurochem ; 78(1): 109-20, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11432978

RESUMO

One of the pathophysiological features of Alzheimer's disease is astrocytosis around senile plaques. Reactive astrocytes may produce proinflammatory mediators, nitric oxide, and subsequent reactive oxygen intermediates such as peroxynitrites. In the present study, we investigated the possible role of the C-terminal fragment of amyloid precursor protein (CT-APP), which is another constituent of amyloid senile plaque and an abnormal product of APP metabolism, as an inducer of astrocytosis. We report that 100 nM recombinant C-terminal 105 amino acid fragment (CT105) of APP induced astrocytosis morphologically and immunologically. CT105 exposure resulted in activation of mitogen-activated protein kinase (MAPK) pathways as well as transcription factor NF-kappaB. Pretreatment with PD098059 and/or SB203580 decreased nitric oxide (NO) production and nuclear factor-kappa B (NF-kappaB) activation. But inhibitors of NF-kappaB activation did not affect MAPKs activation whereas they abolished NO production and attenuated astrocytosis. Furthermore, conditioned media derived from CT105-treated astrocytes enhanced neurotoxicity and pretreatment with NO and peroxynitrite scavengers attenuated its toxicity. These suggest that CT-APP may participate in Alzheimer's pathogenesis through MAPKs- and NF-kappaB-dependent astrocytosis and iNOS induction.


Assuntos
Precursor de Proteína beta-Amiloide , Gliose/induzido quimicamente , Neurotoxinas , Fragmentos de Peptídeos , Precursor de Proteína beta-Amiloide/farmacologia , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Células Cultivadas , Indução Enzimática , Humanos , Proteínas Quinases Ativadas por Mitógeno/fisiologia , NF-kappa B/fisiologia , Neurotoxinas/farmacologia , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo II , Fragmentos de Peptídeos/farmacologia , Ratos
18.
Biochem Biophys Res Commun ; 284(2): 261-7, 2001 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-11394871

RESUMO

3-hydroxykynurenine (3HK), an endogenous metabolite of tryptophan in the kynurenine pathway, is a potential neurotoxin in several neurodegenerative disorders. Stabilizing protein structure, heat shock proteins (HSPs) have diverse roles as molecular chaperones to mediate stress tolerance. In the present study, we investigated the possible protective role of HSPs against 3HK induced neuronal cell death. Here we report that 3HK induced in a dose- and time-dependent manner neuronal cell death in neuroblastoma SK-N-SH cells. The cell death showed characteristic apoptotic features such as cell shrinkage, plasma membrane blebbing, chromatin condensation, and nuclear condensation and fragmentation. Furthermore, SK-N-SN cells were protected from 3HK induced cytotoxicity by prior elevation of HSPs expression. Our results show that the protective effect was abolished by HSP90 anti-sense oligonucleotides while not by HSP27 and HSP70 anti-sense oligonucleotides. Also, our result shows that HSP90 effectively inhibits caspases activities leading to the apoptosis. These results suggest that 3HK induces apoptosis in neuroblastoma SK-N-SN cells and that HSP90 is major contributing protein component of protection against 3HK induced apoptosis.


Assuntos
Apoptose , Proteínas de Choque Térmico HSP90/metabolismo , Proteínas de Choque Térmico , Cinurenina/análogos & derivados , Cinurenina/toxicidade , Neuroblastoma/metabolismo , Neurônios/metabolismo , Apoptose/efeitos dos fármacos , Bisbenzimidazol , Western Blotting , Caspases/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ativação Enzimática/efeitos dos fármacos , Proteínas de Choque Térmico HSP27 , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico HSP90/genética , Proteínas de Choque Térmico HSP90/farmacologia , Resposta ao Choque Térmico , Humanos , Cinurenina/antagonistas & inibidores , Chaperonas Moleculares , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Neuroblastoma/patologia , Neurônios/citologia , Neurônios/efeitos dos fármacos , Oligonucleotídeos Antissenso/farmacologia , RNA Mensageiro/antagonistas & inibidores , RNA Mensageiro/metabolismo , Temperatura
19.
Int J Oncol ; 17(3): 487-94, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10938388

RESUMO

Phorbol esters such as phorbol 12-myristate 13-acetate (PMA) have been reported to modulate diverse cellular responses through signal transduction pathways including the protein kinase C (PKC) pathway. In the present study, we sought to determine the effect of PMA on mucin gene expression and on the biological properties of a human colon cancer cell line, HM3. The cells were treated for 8 and 24 h with various concentrations of PMA and total RNA was extracted and Northern and slot blot analyses were carried out using MUC2, MUC3 and MUC5AC mucin cDNA probes to assess the steady state levels of mRNA. Spent media were collected and the level of cancer associated carbohydrate antigens (T, Tn, sialyl Tn, sialyl Lex, and sialyl Lea) and matrix-degrading metalloproteinase (MMPs) activity were examined. Trypsinized cells were used for assessing in vitro invasion, motility and adhesion to matrigel. Our results showed that PMA caused upregulation of steady state mRNA levels of MUC2, MUC3 and MUC5AC which was inhibited after treatment with protein synthesis inhibitors. Calphostin C, a highly specific inhibitor of protein kinase C significantly inhibited the PMA induced induction of mRNA levels of MUC2, MUC3, and MUC5AC. The levels of all cancer-associated mucin carbohydrate antigens examined in the media were increased by PMA treatment. PMA also caused an increase in MMPs activity and in in vitro invasion and motility properties, but did not affect adhesion of HM3 cells to matrigel. Thus, PMA caused a significant increase in the expression of all three mucin genes through signaling pathways involving protein kinase C and increased secretion of mucin associated carbohydrate antigens. These changes were associated with increases in MMP activity as well as by increases in the invasive and motility properties of HM3 colon cancer cells. These data suggest that protein kinase C signaling pathways may be involved in mucin gene regulation and in modulating the invasive and metastatic properties of colon cancer cells.


Assuntos
Adenocarcinoma/patologia , Carcinógenos/farmacologia , Neoplasias do Colo/patologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Mucinas/biossíntese , Proteínas de Neoplasias/biossíntese , Transdução de Sinais/efeitos dos fármacos , Acetato de Tetradecanoilforbol/farmacologia , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Antígenos de Neoplasias/biossíntese , Antígenos de Neoplasias/genética , Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Colágeno , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Combinação de Medicamentos , Indução Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Humanos , Laminina , Metaloendopeptidases/biossíntese , Metaloendopeptidases/genética , Mucina-5AC , Mucina-2 , Mucina-3 , Mucinas/genética , Naftalenos/farmacologia , Invasividade Neoplásica , Proteínas de Neoplasias/genética , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/metabolismo , Proteoglicanas , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , RNA Neoplásico/biossíntese , RNA Neoplásico/genética , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/metabolismo
20.
Plant Cell Physiol ; 41(3): 354-62, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10805599

RESUMO

Two cDNA clones, pOS-ACO2 and pOS-ACO3, encoding 1-aminocyclopropane-1-carboxylate (ACC) oxidase were isolated from rice seedling cDNA library. pOS-ACO3 is a 1,299 bp full-length clone encoding 321 amino acids (Mr=35.9 kDa), while pOS-ACO2 is 1,072 bp long and is a partial cDNA clone encoding 314 amino acids. These two deduced amino acid sequences share 70% identity, and display a high degree of sequence identity (72-92%) with previously isolated pOS-ACO1 of deepwater rice. The chromosomal location studies show that OS-ACO2 is positioned on the long arm of chromosome 9, while OS-ACO3 on the long arm of chromosome 2 of rice genome. A marked increase in the level of OS-ACO2 transcript was observed in IAA-treated etiolated rice seedlings, whereas the OS-ACO3 mRNA was greatly accumulated by ethylene treatment. Results of ethylene inhibitor studies indicated that auxin promotion of the OS-ACO2 transcription was not mediated through the action of auxin-induced ethylene. Thus, it appears that there are two groups of ACC oxidase transcripts in rice plants, either auxin-induced or ethylene-induced. The auxin-induced OS-ACO2 expression was partially inhibited by ethylene, while ethylene induction of OS-ACO3 transcription was completely blocked by auxin. These results indicate that the expression of ACC oxidase genes is regulated by complex hormonal networks in a gene specific manner in rice seedlings. Okadaic acid, a potent inhibitor of protein phosphatase, effectively suppressed the IAA induction of OS-ACO2 expression, suggesting that protein dephosphorylation plays a role in the induction of ACC oxidase by auxin. A scheme of the multiple regulatory pathways for the expression of ACC oxidase gene family by auxin, ethylene and protein phosphatase is presented.


Assuntos
Aminoácido Oxirredutases/genética , Etilenos/metabolismo , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos/metabolismo , Oryza/metabolismo , Aminoácido Oxirredutases/metabolismo , Sequência de Aminoácidos , Northern Blotting , Southern Blotting , Mapeamento Cromossômico , Dados de Sequência Molecular , Oryza/genética , Reação em Cadeia da Polimerase , RNA de Plantas/análise
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...