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1.
Mol Psychiatry ; 21(10): 1358-65, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-26552591

RESUMO

Depression is associated with alterations in corticostriatal reward circuitry. One pathophysiological pathway that may drive these changes is inflammation. Biomarkers of inflammation (for example, cytokines and C-reactive protein (CRP)) are reliably elevated in depressed patients. Moreover, administration of inflammatory stimuli reduces neural activity and dopamine release in reward-related brain regions in association with reduced motivation and anhedonia. Accordingly, we examined whether increased inflammation in depression affects corticostriatal reward circuitry to lead to deficits in motivation and goal-directed motor behavior. Resting-state functional magnetic resonance imaging was conducted on 48 medically stable, unmedicated outpatients with major depression. Whole-brain, voxel-wise functional connectivity was examined as a function of CRP using seeds for subdivisions of the ventral and dorsal striatum associated with motivation and motor control. Increased CRP was associated with decreased connectivity between ventral striatum and ventromedial prefrontal cortex (vmPFC) (corrected P<0.05), which in turn correlated with increased anhedonia (R=-0.47, P=0.001). Increased CRP similarly predicted decreased dorsal striatal to vmPFC and presupplementary motor area connectivity, which correlated with decreased motor speed (R=0.31 to 0.45, P<0.05) and increased psychomotor slowing (R=-0.35, P=0.015). Of note, mediation analyses revealed that these effects of CRP on connectivity mediated significant relationships between CRP and anhedonia and motor slowing. Finally, connectivity between striatum and vmPFC was associated with increased plasma interleukin (IL)-6, IL-1beta and IL-1 receptor antagonist (R=-0.33 to -0.36, P<0.05). These findings suggest that decreased corticostriatal connectivity may serve as a target for anti-inflammatory or pro-dopaminergic treatment strategies to improve motivational and motor deficits in patients with increased inflammation, including depression.


Assuntos
Corpo Estriado/metabolismo , Transtorno Depressivo Maior/metabolismo , Transtorno Depressivo Maior/fisiopatologia , Adulto , Anedonia/fisiologia , Encéfalo/metabolismo , Mapeamento Encefálico/métodos , Mapeamento Encefálico/psicologia , Proteína C-Reativa/metabolismo , Córtex Cerebral/metabolismo , Depressão/metabolismo , Depressão/fisiopatologia , Dopamina/metabolismo , Feminino , Humanos , Inflamação/complicações , Inflamação/imunologia , Inflamação/metabolismo , Inflamação/psicologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Motivação/fisiologia , Vias Neurais/fisiopatologia , Recompensa
2.
Clin Exp Dermatol ; 40(5): 479-84, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25683452

RESUMO

BACKGROUND: Traditionally, the gold standard for diagnosis of onychomycosis has been the combination of direct microscopy with potassium hydroxide (KOH) staining and fungal culture. However, several studies have suggested that periodic-acid-Schiff (PAS) staining of nail-plate clippings may be a very sensitive method for the diagnosis of onychomycosis. AIM: To compare the sensitivities of direct microscopy with KOH, fungal culture and PAS staining of nail-plate clippings, and to define an efficient, high-yield and cost-effective diagnostic strategy for the diagnosis of onychomycosis in the clinical setting. METHODS: We evaluated a total of 493 patients with clinically suspected onychomycosis. Group A comprised 400 patient samples, evaluated using fungal culture and PAS stain, while group B comprised 93 patient samples evaluated using KOH, fungal culture and PAS. Diagnosis of onychomycosis was defined as clinical morphology plus at least one positive test result. RESULTS: In group A, sensitivities of fungal culture and PAS were 49.5% and 93.1% (P < 0.005), respectively. In group B, the most sensitive single test was PAS (88.2%) followed by KOH (55.9%) and fungal culture (29.4%). The combination of fungal culture and PAS (94.1%) was significantly (P < 0.001) more sensitive than that of KOH and culture (72.1%). CONCLUSION: PAS staining of nail clippings is much more sensitive than KOH and fungal culture for the diagnosis of onychomycosis. Based on our results, we propose a diagnostic algorithm for onychomycosis that takes into consideration the sensitivity, cost-effectiveness and necessary time for each test.


Assuntos
Algoritmos , Dermatoses do Pé/diagnóstico , Dermatoses da Mão/diagnóstico , Microscopia/métodos , Onicomicose/diagnóstico , Adulto , Idoso , Feminino , Corantes Fluorescentes , Dermatoses do Pé/microbiologia , Fungos/isolamento & purificação , Dermatoses da Mão/microbiologia , Humanos , Hidróxidos , Indicadores e Reagentes , Masculino , Pessoa de Meia-Idade , Micologia/métodos , Onicomicose/microbiologia , Reação do Ácido Periódico de Schiff , Compostos de Potássio , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Coloração e Rotulagem/métodos
3.
Int J Obes (Lond) ; 38(8): 1035-43, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24173405

RESUMO

OBJECTIVE: Adipogenesis can be spatially and temporally regulated by extracellular matrix (ECM). We hypothesized that the regulation of hyaluronic acid (HA), a component of the ECM, can affect adipogenesis in fat cells. The effects of HA on adipogenesis were investigated in vitro in 3T3-L1 cells and in vivo in high-fat diet-feeding C57BL/6J mice. METHODS: We investigated the effects of HA by degradation of pre-existing or synthesized HA and artificial inhibition of HA synthesis in adipogenesis. RESULTS: In vitro adipogenesis in 3T3-L1 cells was inhibited by treating them with exogenous hyaluronidase (HYAL) and with 4-methylumbelliferone, which inhibited the synthesis of HA in a concentration-dependent manner. In vivo, abdominal fat accumulation in high-fat diet-feeding C57BL/6J mice was suppressed by exogenous HYAL 10(4) IU injections, which was associated with reduction of lipid accumulation in liver and increase of insulin sensitivity. CONCLUSION: Changes in the ECM such as accumulation of high molecular weight of HA by HAS and degradation of HA by endogenous HYAL were essential for adipogenesis both in vitro and in vivo.


Assuntos
Células 3T3-L1/metabolismo , Gordura Abdominal/metabolismo , Adipogenia , Dieta Hiperlipídica , Matriz Extracelular/metabolismo , Ácido Hialurônico/metabolismo , Animais , Diferenciação Celular , Regulação para Baixo , Regulação da Expressão Gênica , Resistência à Insulina , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Obesidade/fisiopatologia , Obesidade/prevenção & controle
4.
J Oral Rehabil ; 39(11): 805-11, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22816736

RESUMO

We tested the effects of cranio-cervical flexion (CCF) on activation of swallowing-related muscles while swallowing liquid in a sample of 45 healthy volunteers. Activation following CCF movement was examined across two positions (supine and sitting) and, three pressure levels and two different postures were examined in each condition, respectively. When CCF was applied, activation of swallowing-related muscles was significantly increased compared to the neutral neck position, and such findings were found across both the supine and sitting positions. Also in the supine position, when the pressure level of the stabilizer was escalated, there was a significant difference in the activity of the swallowing-related muscles compared to the baseline level. In conclusion, our results suggest that CCF may be a viable method to enhance the effectiveness of swallowing-related muscles by changing neck position. When CCF is applied, the stability of the deep flexor muscles must be secured first after which superficially located muscles may better assist swallowing with less effort.


Assuntos
Vértebras Cervicais/fisiologia , Deglutição/fisiologia , Movimentos da Cabeça/fisiologia , Músculos do Pescoço/fisiologia , Músculos Faríngeos/fisiologia , Adolescente , Biorretroalimentação Psicológica/fisiologia , Eletromiografia , Retroalimentação Sensorial/fisiologia , Feminino , Humanos , Masculino , Postura/fisiologia , Pressão , Amplitude de Movimento Articular/fisiologia , Decúbito Dorsal/fisiologia , Adulto Jovem
5.
J Exp Med ; 181(5): 1899-904, 1995 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-7722465

RESUMO

The mouse mammary tumor virus-7 superantigen (vSAG7) is proteolytically processed in B cells at as many as three positions. Proteolytic processing appears to be important for superantigen activity because a processed form of vSAG7 was predominant among those forms that were found to bind to major histocompatibility complex class II molecules. To determine the functional significance of proteolytic processing, a mutation was introduced in vSAG7 at one of the sites where proteolytic cleavage is thought to take place in B cells. Elimination of the putative processing site at position 171 abrogated detectable vSAG7 surface expression in B cells, indicating that proteolytic processing is required for vSAG7 function. Coexpression in insect cells of vSAG7 and furin, a proprotein-processing enzyme, also demonstrated that furin could process vSAG7 at position 171.


Assuntos
Apresentação de Antígeno , Antígenos Virais/metabolismo , Gammaretrovirus/imunologia , Superantígenos/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Furina , Dados de Sequência Molecular , Spodoptera , Subtilisinas/metabolismo , Células Tumorais Cultivadas
6.
Scand J Rheumatol ; 39(3): 190-6, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20141484

RESUMO

OBJECTIVE: The interleukin (IL)-1 family and its related family members are primary inflammatory cytokines. The aim of this study was to assess the possible association between nine IL-1 family gene polymorphisms and rheumatoid arthritis (RA). METHODS: To investigate the genetic association between IL-1 family gene polymorphisms and the risk of RA in a Korean population, 69 single nucleotide polymorphisms (SNPs) of the nine IL-1 family gene regions were selected. A total of 806 subjects (498 controls and 308 RA patients) were included in the study. The genotypes of the selected SNPs in the IL-1 family genes were determined using Illumina Sentrix Array Matrix chips. SNP Stats, Haploview, and SNP Analyzer, and Helixtree programs were used for the analysis of the genetic data. RESULTS: We observed statistically significant associations between the SNPs of IL1F10 and IL1RN among the IL-1 family genes in the RA patients and the control population. When the patients were divided into two groups according to the parameters of disease activity, including C-reactive protein (CRP) level (> or = 0.5 or < 0.5 mg/dL), the erythrocyte sedimentation rate (ESR) (> or = 30 or < 30 mm/h), and parameters of severity, including rheumatoid factor (RF), anti-cyclic citrullinated peptide (anti-CCP), and bone erosion (positive or not), we found significant associations between the parameters, including CRP, ESR, and bone erosion, and SNPs of the IL-1 family genes in RA. CONCLUSION: This study suggests that IL-1 family gene (IL1F10 and IL1RN) polymorphisms may play an important role in the susceptibility to developing RA.


Assuntos
Artrite Reumatoide/genética , Povo Asiático/genética , Interleucina-1/genética , Polimorfismo de Nucleotídeo Único/genética , Adulto , Alelos , Sedimentação Sanguínea , Proteína C-Reativa , Estudos de Casos e Controles , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Reação em Cadeia da Polimerase , Análise de Regressão , República da Coreia
7.
J Appl Microbiol ; 108(5): 1694-701, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-19849772

RESUMO

AIMS: To develop a rapid, sensitive, specific tool for the detection and quantification of Lactococcus garvieae in food and environmental samples. METHODS AND RESULTS: A real-time quantitative PCR (qPCR) assay with primers for CAU12F and CAU12R based on the 16S rRNA gene of L. garvieae was successfully established. The limit of detection for L. garvieae genomic DNA was 1 ng DNA in conventional PCR and 32 fg with a mean C(T) value of 36.75 in qPCR. Quantification of L. garvieae vegetative cells was linear (R(2) = 0.99) over a 7-log-unit dynamic range down to ten L. garvieae cells. CONCLUSIONS: This method is highly specific, sensitive and reproducible for the detection of L. garvieae compared to gel-based conventional PCR assays, thus providing precise quantification of L. garvieae in food and natural environments. SIGNIFICANCE AND IMPACT OF THE STUDY: This work provides efficient diagnostic and monitoring tools for the rapid identification of L. garvieae, an emerging pathogen in aquaculture and an occasional human pathogen from other members of the genus Lactobacillus.


Assuntos
Microbiologia Ambiental , Microbiologia de Alimentos/métodos , Lactococcus/fisiologia , Humanos , Lactococcus/genética , Lactococcus/isolamento & purificação , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética , Sensibilidade e Especificidade
8.
Cell Death Differ ; 15(1): 192-201, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17962816

RESUMO

Rapid phagocytic clearance of apoptotic cells is crucial for the prevention of both inflammation and autoimmune responses. Phosphatidylserine (PS) at the external surface of the plasma membrane has been proposed to function as a general 'eat me' signal for apoptotic cells. Although several soluble bridging molecules have been suggested for the recognition of PS, the PS-specific membrane receptor that binds directly to the exposed PS and provides a tickling signal has yet to be definitively identified. In this study, we provide evidence that stabilin-2 is a novel PS receptor, which performs a key function in the rapid clearance of cell corpses. It recognizes PS on aged red blood cells and apoptotic cells, and mediates their engulfment. The downregulation of stabilin-2 expression in macrophages significantly inhibits phagocytosis, and anti-stabilin-2 monoclonal antibody provokes the release of the anti-inflammatory cytokine, transforming growth factor-beta. Furthermore, the results of time-lapse video analyses indicate that stabilin-2 performs a crucial function in the rapid clearance of aged and apoptotic cells. These data indicate that stabilin-2 is the first of the membrane PS receptors to provide tethering and tickling signals, and may also be involved in the resolution of inflammation and the prevention of autoimmunity.


Assuntos
Apoptose , Moléculas de Adesão Celular Neuronais/metabolismo , Eritrócitos/metabolismo , Macrófagos/metabolismo , Fagocitose , Fosfatidilserinas/metabolismo , Receptores de Superfície Celular/metabolismo , Apoptose/fisiologia , Sequência de Bases , Citocinas/metabolismo , Envelhecimento Eritrocítico , Eritrócitos/citologia , Humanos , Lipossomos/metabolismo , Dados de Sequência Molecular , RNA Mensageiro/metabolismo , Fator de Crescimento Transformador beta/metabolismo
10.
J Dairy Sci ; 89(1): 90-4, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16357271

RESUMO

Extraction properties of different solvents (chloroform/methanol, hexane/isopropanol, and hexane) were studied for the gas chromatographic analysis of conjugated linoleic acids (CLA) from probiotic bacteria grown in de Man, Rogosa, and Sharpe medium. As compared with chloroform/methanol and hexane/isopropanol, hexane showed comparable extraction efficiency for CLA from unspent de Man, Rogosa, and Sharpe medium, but showed minimal extraction of oleic acid originated from the emulsifier in broth. The extraction efficiency of CLA by hexane was influenced by the broth pH, showing the optimal pH of 7.0. Repeated extraction with hexane increased the yield. Extraction with hexane showed excellent recovery of spiked CLA from the spent broth with up to 97.2% (standard deviation of 1.74%). This represents the highest recovery of CLA from culture broth ever reported. The sample size was also successfully reduced to 0.5 mL to analyze CLA from the broth without impairment of analytical data. This smaller sample size in the 1.5-mL microcentrifuge tube using a small bench-top centrifuge reduced analytical time significantly.


Assuntos
Cromatografia Gasosa/métodos , Hexanos , Ácidos Linoleicos Conjugados/isolamento & purificação , 2-Propanol , Bifidobacterium/crescimento & desenvolvimento , Bifidobacterium/metabolismo , Clorofórmio , Meios de Cultura , Concentração de Íons de Hidrogênio , Metanol , Probióticos/metabolismo , Solventes
12.
Eur J Cancer ; 37(16): 2104-10, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11597391

RESUMO

Dietary organosulphur compounds including diallylsulphide, a component of garlic oil, were shown to inhibit the proliferation of tumour cells. Since hepatocellular carcinoma is one of the most lethal malignancies and there is no effective preventive measure to date, we wished to pursue the chemopreventive potential of the synthetic allylthiopyridazine derivatives (K compounds) on hepatocarcinoma cells. Here, we report that the K compounds efficiently inhibited SK-Hep-1 cell proliferation through induction of apoptosis. Increased chain length at the 3-position of allylthiopyridazine ring improved the potency of growth inhibition. K compounds downregulated Bcl-2, while Bax remained unchanged, reducing the ratio of Bcl-2 to Bax. We also provide evidence that the K compound-induced apoptosis involves cytochrome c release and caspase-3 activation. These results suggest that the allythiopyridazine derivatives, especially 3-propoxy-6-allylthiopyridazine, induce apoptosis in SK-Hep-1 cells through a caspase-3-dependent mechanism, which may contribute to the chemopreventive function for hepatocellular carcinoma.


Assuntos
Anticarcinógenos/farmacologia , Carcinoma Hepatocelular/patologia , Caspases/fisiologia , Neoplasias Hepáticas/patologia , Piridazinas/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/enzimologia , Carcinoma Hepatocelular/metabolismo , Caspase 3 , Caspases/metabolismo , Grupo dos Citocromos c/metabolismo , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Humanos , Neoplasias Hepáticas/enzimologia , Neoplasias Hepáticas/metabolismo , Mitocôndrias Hepáticas/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Piridazinas/química , Relação Estrutura-Atividade , Células Tumorais Cultivadas , Proteína X Associada a bcl-2
13.
Neuroscience ; 97(3): 495-504, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10828532

RESUMO

The present study used mice deficient for dopamine D(2) and D(3) receptors to test whether the expression of these two members of the D(2) class of receptors is essential for the normal expression of three markers that characterize the neurochemical differentiation of the striatum: the calcium-binding protein calbindin, tyrosine hydroxylase and acetylcholinesterase. Results from these experiments revealed that the expression of striatal tyrosine hydroxylase (the rate-limiting enzyme of dopamine synthesis) and acetylcholinesterase is unaffected even by the combined knockout of D(2) and D(3) receptors. However, D(2) and D(3) receptor knockouts differently affect the striatal expression of calbindin-D(28k) immunoreactivity. Prominent changes in the cellular distribution of calbindin are detected in striatal neurons of D(2) mutant mice. Whereas calbindin immunolabeling of wild-type neurons is prominent in the nuclei and the cytoplasm of medium spiny neurons, in D(2) mutant mice, calbindin immunoreactivity is concentrated exclusively in the cytoplasmic rim of these neurons. Such changes in the cellular distribution of calbindin expression are not detected in mice lacking D(3) receptors. In these mutants, however, a lesser density of calbindin-immunoreactive neuropil is detected in the ventral portions of the striatum, i.e. in regions in which D(3) receptors are thought to be expressed at highest levels. Mice lacking both D(2) and D(3) receptors show both phenotypes. The altered cellular distribution of calbindin in D(2) mutants is likely to have functional consequences for some of the Ca(2+)-mediated cellular functions. The topography of the decreased density of striatal calbindin immunorectivity in D(3) mutants suggests a role for D(3) receptors in supporting the expression of striatal calbindin. The observation that mice lacking both D(2) and D(3) receptors show a combination of the D(2) and D(3) mutant phenotypes indicates that each of the different phenotypes detected in the single mutants is indeed related to the lack of the two different D(2)-like receptor subtypes.


Assuntos
Neostriado/metabolismo , Neurônios/metabolismo , Receptores de Dopamina D2/deficiência , Proteína G de Ligação ao Cálcio S100/metabolismo , Acetilcolinesterase/metabolismo , Animais , Calbindinas , Feminino , Masculino , Camundongos , Camundongos Knockout , Neostriado/citologia , Neurônios/citologia , Receptores de Dopamina D2/genética , Receptores de Dopamina D3 , Tirosina 3-Mono-Oxigenase/metabolismo
14.
Neuroscience ; 91(3): 911-24, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10391470

RESUMO

Within the D2-class of dopamine receptors, the D2 and D3 subtypes share the highest degree of similarity in their primary structure. However, the extent to which these two receptor subtypes have similar or different functional properties is unclear. The present study used gene targeting to generate mice deficient for D2, D3, and D2/D3 receptors. A comparative analysis of D2 and D3 single mutants and D2/D3 double mutants revealed that D2/D3 double mutants develop motor phenotypes that, although qualitatively similar to those seen in D2 single mutants, are significantly more severe. Furthermore, increased levels of the dopamine metabolites dihydroxyphenyl acetic acid and homovanillic acid are found in the dorsal striatum of D2 single mutants. The levels of these metabolites, however, are significantly higher in mice lacking D2 and D3 receptors. In addition, results of immunoprecipitation experiments revealed that D2 single mutants express higher levels of D3 receptor proteins during later stages of their postnatal development. These results suggest that D3 receptors compensate for some of the lacking D2 receptor functions and that these functional properties of D3 receptors, detected in mice with a D2 mutant genetic background, remain masked when the abundant D2 receptor is expressed.


Assuntos
Atividade Motora/fisiologia , Receptores de Dopamina D2/deficiência , Animais , Animais Recém-Nascidos/genética , Animais Recém-Nascidos/metabolismo , Animais Recém-Nascidos/fisiologia , Encéfalo/metabolismo , Dopamina/fisiologia , Heterozigoto , Camundongos , Camundongos Knockout/genética , Camundongos Knockout/fisiologia , Fenótipo , Receptores de Dopamina D2/genética , Receptores de Dopamina D2/metabolismo , Receptores de Dopamina D3
15.
Cancer Lett ; 165(2): 139-45, 2001 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-11275362

RESUMO

Hepatocellular carcinoma is one of the most lethal malignancies and there is no effective preventive measure in this highly malignant disease to date. In the present study, we investigated the chemopreventive potential of capsaicin (8-methyl-N- vanillyl-6-nonenamide), the principal pungent ingredient found in hot red pepper, in SK-Hep-1 hepatocellular carcinoma cells. Treatment of capsaicin inhibited growth of SK-Hep-1 cells in a concentration-dependent manner while 4-methoxy capsaicin (Met-capsaicin) was less potent. This inhibitory effect of capsaicin on SK-Hep-1 cell growth was mainly due to the induction of apoptosis as evidenced by DNA fragmentation and nuclear condensation. Furthermore, capsaicin prominently reduced the ratio of anti-apoptotic Bcl-2 to pro-apoptotic Bax and consequently increased caspase-3 activity. These results demonstrate that capsaicin efficiently induced apoptosis in SK-Hep-1 cells through a caspase-3-dependent mechanism, which may contribute to its chemopreventive function.


Assuntos
Anticarcinógenos/farmacologia , Apoptose/efeitos dos fármacos , Capsaicina/farmacologia , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Caspases/metabolismo , Regulação para Baixo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Anticarcinógenos/química , Western Blotting , Capsaicina/análogos & derivados , Capsaicina/química , Caspase 3 , Divisão Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Fragmentação do DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ativação Enzimática , Humanos , Microscopia de Fluorescência , Células Tumorais Cultivadas
16.
J Agric Food Chem ; 47(2): 704-8, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10563957

RESUMO

Partially hydrogenated soybean oil samples were collected during selective and nonselective hydrogenation processes. The formation of conjugated linoleic acids (CLAs) during hydrogenation was greatly dependent on the types and duration of hydrogenation processes. During hydrogenation processes, CLA contents increased initially. After reaching maximum CLA content, the content decreased during hydrogenation. Selective hydrogenation was much more favorable for the formation of conjugated linoleic acids. With nonselective hydrogenation process, the total CLA content was a maximum (9.06 mg total CLA/g oil) at 35 min. However, with the selective hydrogenation process, the total CLA content was a maximum (98.27 mg total CLA/g oil) at 210 min. The CLA contents in some of the tested selectively hydrogenated soybean oils were among the highest ever reported in foods.


Assuntos
Ácido Linoleico/análise , Óleo de Soja/análise , Ésteres/síntese química , Ésteres/química , Cromatografia Gasosa-Espectrometria de Massas , Hidrogenação , Isomerismo , Espectrofotometria Ultravioleta
17.
J Agric Food Chem ; 49(6): 3010-6, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11410002

RESUMO

The effects of hydrogen temperature and agitation rate on the formation of total conjugated linoleic acids (CLA) and CLA isomers were studied during hydrogenation with a selective Ni catalyst. The CLA isomers were identified by using a 100-m cyano-capillary column gas chromatograph and a silver ion-impregnated HPLC. Reaction temperature and agitation rate greatly affected the quantities of total CLA and individual CLA isomers, and the time to reach the maximum quantity of CLA in the partially hydrogenated soybean oil. As the hydrogenation temperature increased, the maximum quantity of CLA in soybean oil increased, but the time to reach the maximum CLA content decreased. By increasing the hydrogenation temperature from 170 to 210 degrees C, the quantity of CLA obtained was about 2.6 times higher. As the agitation rate decreased, the CLA formation in soybean oil increased, and the time to reach the maximum CLA content also increased. The maximum CLA contents in soybean oil obtained during hydrogenation at 210 degrees C with agitation rates of 300, 500, and 700 rpm were 162.82, 108.62, and 66.15 mg total CLA/g oil, respectively. The present data showed that it is possible to produce high-CLA-content soybean oil without major modification of fatty acid composition by short-time (10 min) selective hydrogenation under high temperature and low agitation rate conditions.


Assuntos
Ácido Linoleico/análise , Óleo de Soja/química , Cromatografia Gasosa , Cromatografia Líquida de Alta Pressão , Hidrogenação , Isomerismo , Cinética , Temperatura
18.
J Agric Food Chem ; 48(9): 3847-50, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10995280

RESUMO

The effects of ascorbic acid on the riboflavin-sensitized photochemical changes in beta-lactoglobulin in an aqueous buffer solution as determined by high performance gel permeation liquid chromatography (HPGPLC), insoluble protein content, and individual amino acid content during fluorescent light illumination were studied. The riboflavin-sensitized photochemical degradation of beta-lactoglobulin was effectively inhibited by ascorbic acid, and its inhibitory effectiveness was concentration dependent. The 0.1% ascorbic acid treatment showed 74.4% inhibition of beta-lactoglobulin degradation as determined by a HPGPLC during 6 h light illumination. Insolubility of beta-lactoglobulin in a buffer solution during light illumination was also effectively decreased by ascorbic acid treatment. The riboflavin-sensitized photochemical reduction of cysteine, histidine, lysine, methionine, and tryptophan in beta-lactoglobulin was high during 6 h fluorescent light illumination. The 0.1% ascorbic acid treatment exhibited 20.8% inhibition of total amino acid degradation in beta-lactoglobulin during 6 h light illumination, showing strong inhibitory activity against the degradation of arginine, aspartic acid, cystein, glycine, histidine, phenylalanine, proline, serine, and tryptophan.


Assuntos
Ácido Ascórbico/química , Lactoglobulinas/química , Riboflavina/química , Soluções Tampão , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Fotoquímica , Conformação Proteica , Água/química
19.
J Agric Food Chem ; 48(4): 1058-63, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10775349

RESUMO

Antiphotooxidative components were isolated from the methanolic extract of Coptis japonica Makino by liquid-liquid partitioning fractionation, subsequent column chromatography on Sephadex LH-20 and silica gel, and preparative silica gel TLC. The isolated compounds were identified as coptisine, jatrorrizhine, berberine, and magnoflorine by a combination of spectroscopic studies using UV-visible, IR, mass-spectrometry, and NMR. Coptisine, jatrorrizhine, and berberine isolated from Coptis japonica Makino showed strong antiphotooxidative activity in the chlorophyll-sensitized photooxidation of linoleic acid. However, these compounds did not show either inhibitory activity against lipid peroxidation in rat liver microsomes nor DPPH radical scavenging activity, indicating that their antiphotooxidative activity was not due to the radical chain reaction breaking ability but due to singlet oxygen quenching activity. Commercially available authentic protoberberines (berberine chloride and palmatine chloride) also showed strong antioxidative activity in the chlorophyll-sensitized photooxidation of linoleic acid. The antiphotooxidative activities of the berberine chloride and palmatine chloride were significantly higher than that of ascorbyl palmitate in the chlorophyll-sensitized photooxidation of linoleic acid. These results clearly showed for the first time the antiphotooxidative properties of protoberberines in chlorophyll-sensitized photooxidation of oil.


Assuntos
Antioxidantes/farmacologia , Alcaloides de Berberina/farmacologia , Berberina/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Óleos de Plantas , Plantas Medicinais , Animais , Antioxidantes/isolamento & purificação , Berberina/isolamento & purificação , Alcaloides de Berberina/química , Alcaloides de Berberina/isolamento & purificação , Clorofila , Microssomos Hepáticos/efeitos dos fármacos , Oxirredução , Extratos Vegetais , Raízes de Plantas , Ratos
20.
J Agric Food Chem ; 47(4): 1700-4, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10564041

RESUMO

Red pepper seeds were roasted with constant stirring for 6, 9, 10, and 12 min at 210 degrees C, and oils were extracted from the roasted red pepper seeds using an expeller. The iodine values and fatty acid compositions of red pepper seed oils did not change with roasting time. The fatty acid composition of the oil obtained from the red pepper seeds roasted for 6 min was 0.24% myristic acid, 13. 42% palmitic acid, 0.33% palmitoleic acid, 2.07% stearic acid, 10. 18% oleic acid, 73.89% linoleic acid, and 0.37% linolenic acid, showing a fatty acid composition similar to that of high-linoleate safflower oil. Thirteen alkylpyrazines were identified in the roasted red pepper seed oils: 2-methylpyrazine, 2,5-dimethylpyrazine, 2,6-dimethylpyrazine, 2-ethylpyrazine, 2-ethyl-6-methylpyrazine, 2-ethyl-5-methylpyrazine, trimethylpyrazine, 2,6-diethylpyrazine, 2-ethyl-3,5-dimethylpyrazine, tetramethylpyrazine, 2, 3-diethyl-5-methylpyrazine, 2-isobutyl-3-methylpyrazine, and 3, 5-diethyl 2-methylpyrazine. The pyrazine content increased markedly as the roasting time increased, showing 2.63, 5.01, 8.48, and 13.10 mg of total pyrazine/100 g of oils from the red pepper seeds roasted for 6, 8, 10, and 12 min, respectively, at 210 degrees C. 2, 5-Dimethylpyrazine in the roasted red pepper seed oil seemed to be the component most responsible for the pleasant nutty aroma of the oils. The oxidative stabilities of oils increased greatly as the roasting time increased.


Assuntos
Capsicum/química , Culinária , Óleos de Plantas/química , Plantas Medicinais , Pirazinas/análise , Condimentos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Sementes/química
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