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2.
J Nutr Health Aging ; 17(3): 280-4, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23459983

RESUMO

BACKGROUND: Selenium is an essential trace element with antioxidant property. Decreased serum selenium concentration with aging had been found in previous report. In this study, we aim to investigate the association between serum selenium and the inflammatory cytokine interleukin-6 in the elderly living in long-term care facilities in Taiwan. MATERIALS AND METHODS: A total of 336 subjects aged 65 years and older (range of age: 65 - 101 years) were recruited from eight long-term care facilities in 2002-2003. Baseline characteristics, anthropometric indices, and biochemical data were obtained. Selenium deficiency was defined as serum selenium concentration < 80 µg/L. Multiple logistic and linear regression analyses were used to examine the relationships between selenium deficiency and interleukin-6 (divided into quartiles). RESULTS: The prevalence of selenium deficiency was 35.6% in men and 43.2% in women, respectively. After adjusting for potential confounders using multiple logistic regression analysis, interleukin-6 quartiles were significantly associated with selenium deficiency. Compared to the interleukin-6 quartile I, the adjusted odds ratios of having selenium deficiency for interleukin-6 quartile II, III, IV were 1.00(0.50~2.01), 1.24 (0.62~2.50), and 2.35(1.15~4.83), respectively. The increasing odds ratios for selenium deficiency in higher interleukin-6 quartiles revealed dose-response effects (p < 0.05). Moreover, multiple linear regression analysis showed that serum selenium was significantly inversely associated with interleukin-6 after adjusting for potential confounders. CONCLUSIONS: Serum selenium was inversely associated with inflammatory cytokine interleukin-6 among elderly living in long-term care facilities in Taiwan. Monitoring serum selenium should be considered in these institutionalized elderly.


Assuntos
Suplementos Nutricionais , Interleucina-6/sangue , Desnutrição/epidemiologia , Selênio/sangue , Selênio/deficiência , Idoso , Idoso de 80 Anos ou mais , Antropometria , Estudos Transversais , Feminino , Humanos , Assistência de Longa Duração , Masculino , Desnutrição/sangue , Desnutrição/etiologia , Casas de Saúde , Razão de Chances , Prevalência , Análise de Regressão , Taiwan/epidemiologia
3.
Histol Histopathol ; 24(9): 1161-9, 2009 09.
Artigo em Inglês | MEDLINE | ID: mdl-19609863

RESUMO

Animal models used to study the pathogenesis of non-alcoholic fatty liver disease (NAFLD) are, in general, either genetically altered, or fed with a diet that is extremely high in fat or carbohydrates. Recent findings support the role of oxidative stress, lipid peroxidation and inflammation as probable causative factors. We hypothesize that not only the amount of dietary fat, but the quality of fat is also important in inducing NAFLD. Based on previous observations that female rats fed a diet comprising unsaturated fatty acids are susceptible to liver injury, we proposed that female rats fed with a diet containing fish oil and dextrose would develop pathological and biochemical features of NAFLD. We fed a highly unsaturated fat diet (30% fish oil) to female Sprague-Dawley rats (180-200g), consumed ad libitum for 8 weeks (NAFLD; n=6-8 ). Control animals (CF; n=6-8) were fed with an isocaloric regular rat chow. At killing, blood and liver samples were collected for serum alanine aminotransferase (ALT), histology and molecular analysis. Each histological sample was evaluated for fatty liver (graded from 0 to 4+ according to the amount of fatty change), necrosis (number of necrotic foci (no./mm2) and inflammation (cells per mm2). The amount of collagen formation was estimated based on the amount of Sirius Red staining. Reverse transcriptase polymerase chain reaction (RT-PCR) was carried out for tumor necrosis factor alpha (TNF-alpha), cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), adiponectin, glutathione peroxidase (GPx), superoxide dismutase (Cu/Zn SOD) and catalase (CAT). Western Blot analysis was done for cyclooxygenases-2 (COX-2), inducible nitric oxide synthase (iNOS) and nitrotyrosine. Electrophoretic mobility shift assay was performed for nuclear factor-kappa B (NF-kB) activity. NAFLD rats had a significantly higher serum ALT level, amount of collagen formation, fatty liver, necrosis and inflammation when compared with the chow-fed control rats. mRNA and protein levels of NF-kB regulated genes, which included TNF-alpha, COX-2 and iNOS were also significantly (p<0.01; p<0.01; p<0.05 respectively) upregulated in the NAFLD group when compared with the chow-fed control rats. mRNA levels of antioxidants CAT and GPX were reduced by 35% and 50% respectively in the NAFLD group. However, Cu/Zn SOD mRNA was similar in both groups. The mRNA level of adiponectin was also reduced in NAFLD group. NF-kB activity was markedly increased in the NAFLD rats (p<0.01). The level of oxidative stress, represented by the formation of nitrotyrosine, was significantly elevated in the NAFLD rats (p<0.01). We conclude that NAFLD rats demonstrated several features of NAFLD, which included fatty liver, inflammation, necrosis, increased oxidative stress, an imbalance between pro and antioxidant enzymes mRNAs, reduced adiponectin levels and upregulation of pro-inflammatory mediators. We propose that female rats fed with a diet containing highly unsaturated fatty acids are an extremely useful model for the study of NAFLD.


Assuntos
Gorduras na Dieta/metabolismo , Modelos Animais de Doenças , Fígado Gorduroso/patologia , Hepatopatias/patologia , Adiponectina/metabolismo , Administração Oral , Alanina Transaminase/sangue , Animais , Estudos de Casos e Controles , Catalase/metabolismo , Colágeno/biossíntese , Ciclo-Oxigenase 2/metabolismo , Gorduras na Dieta/administração & dosagem , Ácidos Graxos Insaturados/administração & dosagem , Feminino , Glutationa Peroxidase/metabolismo , Inflamação/induzido quimicamente , Inflamação/etiologia , Inflamação/patologia , Hepatopatias/etiologia , Necrose/induzido quimicamente , Necrose/etiologia , Necrose/patologia , Óxido Nítrico Sintase Tipo II/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo , Fatores de Tempo , Fator de Necrose Tumoral alfa/metabolismo
4.
Eur J Pharm Sci ; 35(1-2): 52-67, 2008 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-18606222

RESUMO

Cancer-cell resistance to chemotherapy limits the efficacy of cancer treatment. The primary mechanisms of multidrug resistance (MDR) are "pump" and "non-pump" resistance. We evaluated the effects and mechanisms of glycocholic acid (GC), a bile acid, on inhibiting pump and non-pump resistance, and increasing the chemosensitivity of epirubicin in human colon adenocarcinoma Caco-2 cells and rat intestine. GC increased the cytotoxicity of epirubicin, significantly increased the intracellular accumulation of epirubicin in Caco-2 cells and the absorption of epirubicin in rat small intestine, and intensified epirubicin-induced apoptosis. GC and epirubicin significantly reduced mRNA expression levels of human intestinal MDR1, MDR-associated protein (MRP)1, and MRP2; downregulated the MDR1 promoter region; suppressed the mRNA expression of Bcl-2; induced the mRNA expression of Bax; and significantly increased the Bax-to-Bcl-2 ratio and the mRNA levels of p53, caspase-9 and -3. This suggests that GC- and epirubicin-induced apoptosis was mediated through the mitochondrial pathway. We conclude that simultaneous suppression of pump and non-pump resistance dramatically increased the chemosensitivity of epirubicin. A combination of anticancer drugs with GC can control MDR via a mechanism that involves modulating P-gp and MRPs as well as regulating apoptosis-related pathways.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/antagonistas & inibidores , Antibióticos Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Epirubicina/farmacologia , Ácido Glicocólico/farmacologia , Animais , Células CACO-2 , Proliferação de Células/efeitos dos fármacos , Cromatina/metabolismo , Cromatografia Líquida de Alta Pressão , DNA de Neoplasias/biossíntese , DNA de Neoplasias/genética , Citometria de Fluxo , Humanos , Mucosa Intestinal/metabolismo , Intestinos/efeitos dos fármacos , Luciferases/química , Luciferases/metabolismo , Masculino , Microscopia de Fluorescência , Plasmídeos/genética , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção
5.
Rev Sci Instrum ; 78(6): 065103, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17614634

RESUMO

A novel microcomputer-based ultrasonic distance measurement system is presented. This study proposes an efficient algorithm which combines both the amplitude modulation (AM) and the phase modulation (PM) of the pulse-echo technique. The proposed system can reduce error caused by inertia delay and amplitude attenuation effect when using the AM and PM envelope square wave form (APESW). The APESW ultrasonic driving wave form causes a phase inversion phenomenon in the relative wave form of the receiver. The phase inversion phenomenon sufficiently identifies the "measurement pulse" in the received wave forms, which can be used for accurate time-of-flight (TOF) measurement. In addition, combining a countertechnique to compute the phase shifts of the last cycle for TOF, the presented system can obtain distance resolution of 0.1% of the wavelength corresponding to the 40 kHz frequency of the ultrasonic wave. The standard uncertainty of the proposed distance measurement system is found to be 0.2 mm at a range of 50-500 mm. The APESW signal generator and phase detector of this measuring system are designed on a complex programmable logic device, which is used to govern the TOF measurement and send the data to a personal computer for distance calibration and examination. The main advantages of this APESW system are high resolution, low cost, narrow bandwidth requirement, and ease of implementation.


Assuntos
Eletrônica , Processamento de Sinais Assistido por Computador/instrumentação , Transdutores , Ultrassom , Desenho de Equipamento , Análise de Falha de Equipamento , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
6.
Aust Dent J ; 52(4): 315-21, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18265688

RESUMO

BACKGROUND: Patients with cleft lip and/or palate (CL&/P) experience a higher caries prevalence. This study aimed to determine if patients with CL&/P, undergoing and not undergoing orthodontic treatment, have a different salivary biochemical profile and different salivary levels of Mutans Streptococci (MS) and Lactobacilli (LB) compared to patients undergoing and not undergoing orthodontic treatment without CL&/P. METHODS: One hundred and ten subjects aged between 12 and 17 years were recruited into one of four different groups comprising two control groups and two treatment groups. The control groups comprised of subjects with and without CL&/P who were not undergoing orthodontic treatment. The treatment groups comprised of subjects with and without CL&/P undergoing orthodontic treatment. Regular reinforcement of oral hygiene instructions, dietary counselling and debridement, when necessary, were offered to subjects in the treatment groups following their orthodontic adjustment appointments. The salivary secretion time, pH of resting and stimulated saliva, salivary flow rate, buffering capacity, quantity of salivary MS and LB were measured. RESULTS: Subjects with CL&/P undergoing orthodontic treatment at the Children's Oral Health Service tended to present with microbiological and salivary profiles that were less favourable for caries development. There was a significant difference in the percentage of subjects with > or = 10(5) colony forming units (CFU)/mL of MS between the cleft treatment and non-cleft treatment groups. Subjects in the non-cleft treatment group had the highest percentage of subjects (86.7 per cent) with > or = 10(5) CFU/mL of MS whereas subjects in the cleft treatment group had the lowest percentage of subjects (60 per cent) with > or = 10(5) CFU/mL of MS. For LB, there were significantly higher percentages of subjects with > or =10(5) CFU/mL of LB in the non-cleft treatment (76.7 per cent) and cleft treatment (73.3 per cent) groups compared to the non-cleft control (46.7 per cent) and cleft control (40.0 per cent) groups. CONCLUSIONS: Regular oral hygiene reinforcement and dental health education appears to have a positive effect in reducing the percentage of subjects with > or = 10(5) CFU/mL of MS.


Assuntos
Fenda Labial/microbiologia , Fissura Palatina/microbiologia , Ortodontia Corretiva , Saliva/microbiologia , Adolescente , Criança , Métodos Epidemiológicos , Feminino , Humanos , Lactobacillus/isolamento & purificação , Masculino , Saliva/química , Células-Tronco , Streptococcus mutans/isolamento & purificação
7.
Int J Clin Pract ; 59(6): 639-44, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15924590

RESUMO

We sought to clarify whether impaired fasting glucose (IFG), impaired glucose tolerance (IGT) or both (IFG/IGT) represent the most severe impairment in insulin resistance (IR) and insulin secretion. Among the 159 Chinese subjects, 21 were diagnosed as having IFG, 103 as having IGT and 35 as having both. IR and beta-cell function were assessed using homeostatic model assessment (HOMA) and an insulin-suppression test (IST). No differences were evident between the groups in blood pressure, body mass index, plasma insulin fasting levels and lipid profiles. However, plasma 2-h insulin levels were higher in the IGT and IFG/IGT groups. Beta-cell functions were not different between these groups. But, the result of glucose tolerance was different, in which the IFG/IGT and IFG groups displayed higher insulin sensitivity than IGT via HOMA instead of no difference via IST in the three patient groups.


Assuntos
Glicemia/metabolismo , Intolerância à Glucose/diagnóstico , Resistência à Insulina , Insulina/metabolismo , Adulto , Povo Asiático , Jejum/metabolismo , Feminino , Teste de Tolerância a Glucose , Homeostase/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Taiwan/etnologia
8.
Pathol Biol (Paris) ; 52(8): 438-43, 2004 Oct.
Artigo em Francês | MEDLINE | ID: mdl-15465261

RESUMO

Within the scope of its health products control mission, the French Health Products Safety Agency (Afssaps) collaborating with two expert's sites, has assessed the 16 tests available on the French market in 2002 for rapid diagnosis of the Streptococcus A tonsillitis. The purpose of this study was to verify the reliability and rapidity of these tests and to give some information to the users about their analytical criteria and practicability characteristics. The analytical study has been performed on a same panel of four reference strains of Streptococcus pyogenes dilutions to determine the limit of detection of all the reagents in the same condition of methodology. The limit of detection has been calculated with the results expressed in colony forming unit by ml (CFU/ml). The practicability study has permitted to analyze the quality of the presentation, the easiness of the final reading and of performing tests. A score has been established for each rapid test. A classification of the analytical sensitivity (limit of detection) and practicability (score) of these 16 devices has been established. The limit of detection of the reagents giving the best results allows the detection of the lowest bacterial concentration of the panel which is 10(5) CFU/ml. Regarding practicability, the results suggest that, the immunochromatographic strip methods have the best score in a view with the use by a non medical laboratory.


Assuntos
Antígenos de Bactérias/análise , Faringite/diagnóstico , Infecções Estreptocócicas/diagnóstico , Streptococcus pyogenes/isolamento & purificação , Técnicas Bacteriológicas/normas , França , Humanos , Faringite/microbiologia , Controle de Qualidade , Reprodutibilidade dos Testes , Tonsilite/diagnóstico , Tonsilite/microbiologia
9.
Histol Histopathol ; 19(1): 95-104, 2004 01.
Artigo em Inglês | MEDLINE | ID: mdl-14702176

RESUMO

The present work studied the induction of cleft palate formation in embryos developed from pregnant BALB/c mice treated orally with retinoic acid (RA). Previous studies on mature somatic cell types showed that RA exerted inhibitory effects on inducible nitric oxide synthase (iNOS) production. For the first time, our study has shown that RA actually stimulates significant expression of iNOS at specific zones of the affected embryonic palatal tissues at three consecutive stages, from gestation day 13 (GD13) to day 16 (GD16). Enzymatically, iNOS facilitates intracellular nitric oxide (NO) synthesis from L-arginine. When NO reacts with reactive superoxides it may result in irreparable cell injury. NO was also reported to induce apoptosis in some mammalian cell systems. Based on our findings, we propose that such an increase in NO production might be associated with apoptosis in the embryonic palatal tissues in the RA-treated mice. The detrimental effects of NO resulted in a reduction in proliferating palatal cells and therefore disturbed the normal plasticity of the palatal shelves. With iNOS overexpression, our findings also showed that there was significant concomitant down-regulation in the expressions of Bone Morphogenetic Proteins (BMPs) -2, 4, and 7 with regional variations particularly in the palatal mesenchymal cells for those embryos developing cleft palate. Since specific spatial and temporal expressions of BMPs -2, 4, and 7 are critical during normal palatal morphogenesis, any deficiency in the epithelial-mesenchymal interaction may result in retarding growth at the embryonic palatal shelves. Taken together, our study has demonstrated cleft palate formation in the BALB/c embryos involved overexpression of iNOS and down-regulation of BMPs-2, 4 and 7.


Assuntos
Proteínas Morfogenéticas Ósseas/metabolismo , Regulação para Baixo , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Óxido Nítrico Sintase/metabolismo , Teratogênicos/farmacologia , Tretinoína/farmacologia , Animais , Proteína Morfogenética Óssea 4 , Proteínas Morfogenéticas Ósseas/genética , Fissura Palatina/induzido quimicamente , Fissura Palatina/embriologia , Fissura Palatina/metabolismo , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos BALB C , Óxido Nítrico Sintase/efeitos dos fármacos , Óxido Nítrico Sintase Tipo II , Fatores de Tempo , Distribuição Tecidual/efeitos dos fármacos
10.
Compr Rev Food Sci Food Saf ; 3(4): 127-139, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33430565

RESUMO

Intense interest in nutraceuticals and their potential benefits has created the need to review the existing scientific information on their effect in preventing and managing inflammation that accompanies most chronic diseases. This article reviews the basic mechanisms of inflammation and the potential of 9 nutraceuticals to be effective as chronic disease preventive agents. Furthermore, the article emphasizes studies in which nutraceuticals are shown to be effective in preventing inflammation and mentions other molecular targets that can be of use in the future. The effects of the following nutraceuticals: α-tocopherol, ascorbic acid, curcumin, resveratrol, (-)-epigallocatechin gallate, theaflavin, genistein, omega-3 fatty acids, and lycopene on reactive oxygen species scavenging ability, as well as proinflammatory targets, such as tumor necrosis factor α interleukin-1, interleukin-1ß, nuclear factor kappa B, cellular and adhesion molecules, cyclooxygenase-2, inducible nitric oxide synthase, 5-lipoxygenase (5-LOX), phospholipase A2 , reactive oxygen species generating enzymes are discussed.

11.
J Agric Food Chem ; 49(12): 5969-74, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11743794

RESUMO

Seven triterpene saponins were isolated from n-butanol fractions of blue cohosh (Caulophyllum thalictroides) roots and rhizomes. Their structures were established by spectral ((1)H NMR, (13)C NMR, 2D-NMR, and APCI-MS) techniques and chemical reactions as hederagenin 3-O-alpha-L-arabinopyranoside (1); caulophyllogenin 3-O-alpha-L-arabinopyranoside (2); hederagenin 3-O-beta-D-glucopyranosyl-(1-->2)-alpha-L-arabinopyranoside (3); 3-O-alpha-L-arabinopyranosyl-hederagenin 28-O-alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl(1-->6)-beta-D-glucopyranoside (4); 3-O-alpha-L-arabinopyranosyl- caulophyllogenin 28-O-alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl(1-->6)-beta-D-glucopyranoside (5); 3-O-beta-D-glucopyranosyl-(1-->2)-alpha-L-arabinopyranosyl- echinocystic acid 28-O-alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl(1-->6)-beta-D-glucopyranoside (6); 3-O-beta-D-glucopyranosyl-(1-->2)-alpha-L-arabinopyranosyl-hederagenin 28-O-alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl(1-->6)-beta-D-glucopyranoside (7). All seven compounds were identified in this species for the first time.


Assuntos
Berberidaceae/química , Rizoma/química , Saponinas/análise , Triterpenos/análise , Sequência de Carboidratos , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Conformação Molecular , Dados de Sequência Molecular , Oligossacarídeos/química , Raízes de Plantas/química
12.
Biochem Pharmacol ; 62(9): 1175-83, 2001 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11705450

RESUMO

The effects of green and black tea polyphenols on cyclooxygenase (COX)- and lipoxygenase (LOX)-dependent arachidonic acid metabolism in normal human colon mucosa and colon cancers were investigated. At a concentration of 30 microg/mL, (-)-epigallocatechin-3-gallate (EGCG), (-)-epigallocatechin (EGC), and (-)-epicatechin-3-gallate (ECG) from green tea and theaflavins from black tea inhibited LOX-dependent activity by 30-75%. The formation of 5-, 12-, and 15-LOX metabolites was inhibited to a similar extent. Tea polyphenols also inhibited COX-dependent arachidonic acid metabolism in microsomes from normal colon mucosa, with ECG showing the strongest inhibition. The formation of thromboxane (TBX) and 12-hydroxyheptadecatrienoic acid (HHT) was decreased to a greater extent than other metabolites. The inhibitory effects of tea polyphenols on COX activity, however, were less pronounced in tumor microsomes than in normal colon mucosal microsomes. Theaflavins strongly inhibited the formation of TBX and HHT, but increased the production of prostaglandin E(2) (PGE(2)) in tumor microsomes. The enhancing effect of theaflavins on PGE(2) production was related to the COX-2 level in the microsomes. Although theaflavin inhibited ovine COX-2, its activity in the formation of PGE(2) was stimulated by theaflavin when ovine COX-2 was mixed with microsomes, suggesting that theaflavin affects the interaction of COX-2 with other microsomal factors (e.g. PGE synthase). The present results indicate that tea polyphenols can affect arachidonic acid metabolism in human colon mucosa and colon tumors, and this action may alter the risk for colon cancer in humans.


Assuntos
Ácido Araquidônico/metabolismo , Biflavonoides , Catequina/análogos & derivados , Neoplasias do Colo/metabolismo , Flavonoides , Mucosa Intestinal/efeitos dos fármacos , Fenóis/farmacologia , Polímeros/farmacologia , Chá/química , Antioxidantes/farmacologia , Catequina/farmacologia , Neoplasias do Colo/enzimologia , Dinoprostona/metabolismo , Inibidores Enzimáticos/farmacologia , Humanos , Mucosa Intestinal/enzimologia , Mucosa Intestinal/metabolismo , Lipoxigenase/metabolismo , Microssomos/efeitos dos fármacos , Microssomos/metabolismo , Prostaglandina-Endoperóxido Sintases/metabolismo , Células Tumorais Cultivadas
13.
J Nat Prod ; 64(11): 1460-2, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11720534

RESUMO

An investigation on the gum exudates of Commiphora myrrha has led to the isolation of six sesquiterpenoids. On the basis of spectroscopic data interpretation, they were determined as two new furanosesquiterpenoids, rel-1S,2S-epoxy-4R-furanogermacr-10(15)-en-6-one (1) and rel-2R-methyl-5S-acetoxy-4R-furanogermacr-1(10)Z-en-6-one (2), and four known furanosesquiterpenoids, rel-3R-methoxy-4S-furanogermacra-1E,10(15)-dien-6-one (3), rel-2R-methoxy-4R-furanogermacr-1(10)E-en-6-one (4), furanogermacra-1(10)Z,4Z-dien-6-one, and curzerenone [6,7-dihydro-5beta-isopropenyl-3,6beta-dimethyl-6-vinylbenzofuran-4(5H)-one]. This is the first report of the relative stereochemistry for the known compounds 3 and 4. Compound 1 exhibited weak cytotoxic activity against a MCF-7 breast tumor cell line in a clonogenic assay, while the other five compounds were inactive in this assay.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Burseraceae/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Sesquiterpenos de Germacrano , Sesquiterpenos/isolamento & purificação , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Mama , Cromatografia em Camada Fina , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Feminino , Humanos , Conformação Molecular , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Plantas Medicinais/química , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Estereoisomerismo , Células Tumorais Cultivadas/efeitos dos fármacos
14.
J Agric Food Chem ; 49(10): 4780-3, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11600021

RESUMO

Three new spirostanol saponins have been isolated from the seeds of Allium tuberosum. On the basis of acid hydrolysis and comprehensive spectroscopic analysis, their structures were established as tuberoside J, (25R)-5alpha-spirostan-2alpha,3beta,27-triol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside; tuberoside K, (25R)-5alpha-spirostan-2alpha,3beta,27-triol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->4)]-beta-D-glucopyranoside; and tuberoside L, 27-O-beta-D-glucopyranosyl-(25R)-5alpha-spirostan-2alpha,3beta,27-triol 3-O-alpha-D-rhamnopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->4)]-beta-D-glucopyranoside.


Assuntos
Allium/química , Saponinas/análise , Espirostanos/análise , Allium/embriologia , Hidrólise , Espectroscopia de Ressonância Magnética , Saponinas/química , Saponinas/isolamento & purificação , Sementes/química , Espectrometria de Massas de Bombardeamento Rápido de Átomos , Esteroides/análise , Esteroides/química , Esteroides/isolamento & purificação
15.
J Agric Food Chem ; 49(9): 4478-81, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11559157

RESUMO

One new iridoid glycoside and five known flavonol glycosides have been isolated from the leaves of Morinda citrifolia. The new iridoid exists as an epimeric mixture in solution. Complete assignments of the proton and carbon chemical shifts for the individual epimers were accomplished on the basis of high-resolution 1D and 2D NMR data. Their antioxidative activities were measured. All of these compounds showed DPPH free radical scavenging activity at the concentration of 30 microM.


Assuntos
Glicosídeos/química , Folhas de Planta/química , Antioxidantes , Flavonoides , Flavonóis , Sequestradores de Radicais Livres , Glicosídeos/análise , Espectroscopia de Ressonância Magnética
16.
Phytochemistry ; 58(2): 227-32, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11551543

RESUMO

Expression of the yeast Delta9 desaturase gene in tomato (Lycopersicon esculentum Mill.) resulted in changes in the profiles of fatty acids in tomato leaves. Transgenic leaves displayed a dramatic increase in cis-Delta9 16:1, which only existed in a small quantity in control leaves. Also higher, but not as dramatic, were 18:1 and 16:3 fatty acids. Several fatty acids, viz. 16:0, 18:0, and 18:3 declined in transgenic leaves. Changes in fatty acids were accompanied by changes in certain volatile compounds derived from fatty acids. On a percentage basis, most notable increases (>3-fold) were 1-hydroxy-2-butanone, 1-penten-3-ol, heptanal, 3-hexen-1-ol, 2-octanol,cis-3-hexenal, hexanal and 2-nonenal. Several flavor compounds not known to be biochemically derived from fatty acids, viz. 2-ethyl-furan, 5-ethyl-2-[5H]-furanone, eugenol, and 2-ethylthiophene also showed sharp increases in transgenic leaves.


Assuntos
Ácidos Graxos/metabolismo , Solanum lycopersicum/metabolismo , Solanum lycopersicum/genética , Folhas de Planta/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Estearoil-CoA Dessaturase/genética , Volatilização
17.
Clin Orthod Res ; 4(1): 3-14, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11553080

RESUMO

Low level laser therapy has been used in treating many conditions with reports of multiple clinical effects including promotion of healing of both hard and soft tissue lesions. Low level laser therapy as a treatment modality remains controversial, however. The effects of wavelength, beam type, energy output, energy level, energy intensity, and exposure regime of low level laser therapy remain unexplained. Moreover, no specific therapeutic window for dosimetry and mechanism of action has been determined at the level of individual cell types. The aim of this study was to investigate the effects of low level laser irradiation on the human osteosarcoma cell line, SAOS-2. The cells were irradiated as a single or daily dose for up to 10 days with a GaAlAs continuous wave diode laser (830 nm, net output of 90 mW, energy levels of 0.3, 0.5, 1, 2, and 4 Joules). Cell viability was not affected by laser irradiation, with the viability being greater than 90% for all experimental groups. Cellular proliferation or activation was not found to be significantly affected by any of the energy levels and varying exposure regimes investigated. Low level laser irradiation did result in a heat shock response at an energy level of 2 J. No significant early or late effects of laser irradiation on protein expression and alkaline phosphatase activity were found. Investigation of intracellular calcium concentration revealed a tendency of a transient positive change after irradiation. Low level laser irradiation was unable to stimulate the osteosarcoma cells utilised for this research at a gross cell population level. The heat shock response and increased intracellular calcium indicate that the cells do respond to low level laser irradiation. Further research is required, utilising different cell and animal models, to more specifically determine the effects of low level laser irradiation at a cellular level. These effects should be more thoroughly investigated before low level laser therapy can be considered as a potential accelerator stimulus for orthodontic tooth movement.

18.
Proc Natl Sci Counc Repub China B ; 25(3): 158-65, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11480771

RESUMO

Dietary factors play important roles in the carcinogenic process. The results of epidemiological data and some laboratory animal studies indicate that certain naturally occurring and synthetic components are able to block the carcinogenic process and inhibit the development of certain cancers. Dibenzoylmethane (DBM), a curcumin-related beta-diketone analogue has been reported to exhibit a remarkable inhibitory effect on 7,12-dimethylbenz[a]anthracene (DMBA)-induced mammary tumorigenesis in Sencar mice. The present study investigated the possible mechanisms of inhibitory action of DBM on DMBA-induced mammary tumorigenesis in mice. The summarized results indicate that: (1) in in-vitro studies. DBM inhibited DMBA metabolism and the formation of DMBA-DNA adducts in a dose-dependent manner; (2) in the assay of competitive binding to estrogen receptors with [3H]-estradiol in vitro, DBM showed weak binding affinity; (3) in vivo, feeding of 1% DBM in the diet of immature Sencar mice for 4 -5 weeks decreased the uterine and parametrial fat pad weights, and lowered the serum estrogen and triglyceride levels. This study provides insight into the mechanisms involved in the inhibitory action of DBM in mouse mammary tumorigenesis.


Assuntos
Anticarcinógenos/farmacologia , Benzoatos/farmacologia , Chalconas , Neoplasias Mamárias Experimentais/prevenção & controle , 9,10-Dimetil-1,2-benzantraceno/farmacocinética , 9,10-Dimetil-1,2-benzantraceno/toxicidade , Animais , Anticarcinógenos/uso terapêutico , Benzoatos/uso terapêutico , Ligação Competitiva , Carcinógenos/farmacocinética , Carcinógenos/toxicidade , Bovinos , Curcumina/análogos & derivados , Curcumina/química , Citosol/química , DNA/efeitos dos fármacos , Adutos de DNA/análise , Dano ao DNA , Gorduras na Dieta/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Estradiol/sangue , Estradiol/metabolismo , Feminino , Hipolipemiantes/farmacologia , Hipolipemiantes/uso terapêutico , Neoplasias Mamárias Experimentais/induzido quimicamente , Camundongos , Camundongos Endogâmicos SENCAR , Microssomos Hepáticos/metabolismo , Estrutura Molecular , Ovariectomia , Progesterona/sangue , Ratos , Ratos Sprague-Dawley , Receptores de Estrogênio/efeitos dos fármacos , Receptores de Estrogênio/metabolismo , Especiarias , Triglicerídeos/sangue , Útero/química
19.
Phytother Res ; 15(5): 441-3, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11507740

RESUMO

Four pyranocoumarins; dipetaline, alloxanthoxyletin, xanthoxyletin and xanthyletin; and two lignans; sesamin and asarinin were isolated from the northern prickly ash, Zanthoxylum americanum. To varying degrees, all inhibited the incorporation of tritiated thymidine into human leukaemia (HL-60) cells. Dipetaline was the most active with an IC(50) of 0.68 ppm, followed by alloxanthoxyletin (1.31 ppm), sesamin (2.71 ppm), asarinin (4.12 ppm), xanthoxyletin (3.48 ppm) and xanthylletin (3.84 ppm).


Assuntos
Antineoplásicos/farmacologia , Cumarínicos/farmacologia , Leucemia/prevenção & controle , Lignanas/farmacologia , Plantas Medicinais , Rosales , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Cumarínicos/química , Cumarínicos/uso terapêutico , Células HL-60/efeitos dos fármacos , Humanos , Lignanas/química , Lignanas/uso terapêutico , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Caules de Planta
20.
Am J Kidney Dis ; 38(2): 256-64, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11479150

RESUMO

Cyclophosphamide (CYC) has proven beneficial in preserving renal function in patients with lupus with diffuse proliferative glomerulonephritis (DPGN). However, the optimal route of CYC administration is unknown because direct comparative studies are unavailable. In this open study, we compared the renal outcome of two historical cohorts of patients with diffuse proliferative lupus nephritis (World Health Organization classes IVa and IVb) treated with either intravenous (IV) pulse CYC (group A; n = 22) or sequential oral CYC followed by azathioprine (AZA; group B; n = 21) and followed up prospectively. Both groups of patients had similar clinical, biochemical, and renal parameters at baseline. At 24 months posttreatment, significant improvements in proteinuria, creatinine clearance, serum albumin level, and lupus serological results were evident in both groups. Compared with patients in group A, patients in group B had more complete or partial remission (90% versus 73%) and less risk for treatment failure (5% versus 14%), renal flares (5% versus 14%), and doubling of creatinine levels (5% versus 9%), but the difference was not statistically significant. However, patients treated with oral immunosuppression had an insignificant increase in rates of herpes zoster infection (19% versus 9%) and menstrual disturbance (50% versus 29%). We conclude that sequential oral immunosuppression with CYC and AZA tended to have better efficacy than IV pulse CYC in the treatment of lupus DPGN but was associated with more toxicities. Additional randomized trials involving a larger cohort of patients with a longer period of observation are necessary.


Assuntos
Azatioprina/administração & dosagem , Ciclofosfamida/administração & dosagem , Nefrite Lúpica/tratamento farmacológico , Administração Oral , Adolescente , Adulto , Azatioprina/efeitos adversos , Biópsia , Ciclofosfamida/efeitos adversos , Quimioterapia Combinada , Feminino , Humanos , Injeções Intravenosas , Rim/patologia , Nefrite Lúpica/patologia , Masculino , Metilprednisolona/administração & dosagem , Pessoa de Meia-Idade , Plasmaferese , Pulsoterapia , Recidiva , Análise de Regressão , Indução de Remissão
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