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1.
Anal Sci ; 34(8): 959-964, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30101892

RESUMO

DNA methyltransferase (MTase) is related to transcriptional repressor activity in biological functions. It is an essential for cancer diagnosis and therapeutics to detect DNA MTase activity sensitively. Here, a fluorescent system based on polymerase amplification has been developed to detect DNA adenine MTase (Dam) activity sensitively. The amplification is triggered by the probe DNA regions a, which are the primes of a polymerase-induced replicated reaction. They come from methylation and a digestion reaction of DNA S1-S1, including a 5'-GATC-3' sequence recognized by Dam MTase and methylation sensitive restriction endonuclease Dpn I. The intensities of fluorescence are dependent on the Dam MTase activity. The method shows fine sensitivity with a detection limit of 3.2 × 10-4 U mL-1 and specificity for Dam MTase. In human serum samples, the method has been successfully applied, and it has also been used to screen the inhibitors, which means that the developed method can be a powerful and potential tool for drug development and clinical diagnosis in the future.


Assuntos
Técnicas Biossensoriais , Ensaios Enzimáticos/métodos , Fluorescência , Técnicas de Amplificação de Ácido Nucleico/métodos , DNA Metiltransferases Sítio Específica (Adenina-Específica)/análise , DNA Metiltransferases Sítio Específica (Adenina-Específica)/metabolismo , Sondas de DNA/química , Sondas de DNA/metabolismo , Humanos , Espectrometria de Fluorescência
2.
Artigo em Inglês | MEDLINE | ID: mdl-27446223

RESUMO

As a medicinal and edible fungus parasitizing on the trees, Perigord Truffle (Tuber huidongense) is well known for its delicious taste, unique smell, and high medical value for healthcare. One new water-soluble nonstarch polysaccharide (PST-W with the yield of 0.41%) from Perigord Truffle (Tuber huidongense) was purified and identified on structural characteristics for the first time. The characterizations of PST-W were studied on physicochemical properties, main components of monosaccharide(s), and molecular structure. The monosaccharide compositions of PST-W were studied and identified as glucan, only containing D-glucoses with the molecular structure of [→6) α-D-Glcp (1 → 6) α-D-Glcp (1→] n by methylation analysis and NMR. In the determination of total reducing capacity, the reducing abilities of polysaccharide extracts could be listed as vitamin C > PST-W > crude polysaccharides-3 > crude polysaccharides-2 > crude polysaccharides-1. All of PST-W, crude polysaccharides-2, and crude polysaccharides-3 were relatively good scavenger for 1,1-Diphenyl-2-picrylhydrazyl radical 2,2-Diphenyl-1-(2,4,6-trinitrophenyl)hydrazyl radicals with IC50 of 2.81, 4.17, and 3.44 mg/mL, respectively. However, O2 (-∙) clearing abilities of PST-W and crude polysaccharides were obviously weaker. The activities of total crude extract were the worst, indicating that the impurities might negatively affect the antioxidant activity. Thus, the separation and purification of polysaccharides were significant to increase the antioxidant activity in some degree.

3.
Zhongguo Zhong Yao Za Zhi ; 40(15): 3009-12, 2015 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-26677702

RESUMO

Derris eriocarpa, a traditional Chinese medicine belonging to the family of Leguminosae, is widely distributed mainly over Yunnan, Guangxi and Guizhou of China. Modern pharmacological researches on this herb showed that it had extensive bioactivities, such as promoting urination, removing dampness and cough and reducing inspissated mucus and other biological activities. The extensive studies on the chemical constituents of this plant have resulted in the isolation of triterpenoids, steroids, fatty acid and others, but the flavone compounds haven't reported before. In our further research on the ethyl acetate of this plant, nine flavone compounds were obtained by column chromatography on silica gel, Sephadex LH-20, semi-prep HPLC, polyamide column chromatography and recrystallization for separation and purification. The structures were determined on the basis of extensive spectroscopic analysis, including MS, NMR experiments and comparison with spectroscopic data in the literature, respectively, as diosmetin (1), 3, 3'-di-O-methylquercetin (2), afromosin (3), 6, 3'-dihydroxy-7, 4'-dimethoxyisoflavone (4), odoratin (5), 7, 3'-dihydroxy-8, 4'-dimethoxyisoflavone (6), 6, 4'-dihydroxy-7, 3'-dimethoxyisoflavone (7), 5, 7, 4'-trihydroxy-3, 3', 5'-trimethoxyflavone (8), and alpinumisoflavone (9). All these compounds were isolated from Derris eriocarpa How for the first time. And the in vitro assays showed that compound 2 possessed moderate inhibitory activity against human cancer cells K562 and HEL.


Assuntos
Derris/química , Flavonoides/isolamento & purificação , Flavonoides/química , Flavonoides/farmacologia , Humanos , Células K562
4.
Zhong Yao Cai ; 37(11): 2047-50, 2014 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-26027130

RESUMO

OBJECTIVE: To study the analgesic effect of Triptolide(TP) in rats with adjuvant and the possible mechanism. METHODS: Fifty healthy SD rats were randomly divided into normal control group (group A), model group (group B), and low(group C), middle (group D) and high(group E) dose TP treatment groups. Except the group A, each group of rats were reared by toe intradermal injection of 0. 1 mL Freund's complete adjuvant. After 14 days,rats in the C, D and E groups were taken different doses (0. 1 mg/kg group C, 0. 2mg/kg group D, and 0. 4 mg/kg group E) by intraperitoneal injection of TP for 9 days, and then thermal withdrawal latency and the expression of NMDAR1 and BSI-B4 binding sites in lumbar5 (L5) spinal dorsal horn and DRG were detected. RESULTS: Thermal withdrawal latency of rats in group B was significantly lower than that of group A (P <0. 01), while those in group C, D and E were significantly higher than those in group B (P <0. 05 or P <0. 01). TP increased the thermal pain threshold by a quantity-effect relationship; NMDAR-1 and BSI-B4 binding sites expression levels were significantly increased in group B than those in group A (P <0. 01), while those in group C, D and E were lower than those in group B. CONCLUSION: Analgesic effect of TP is related to reducing levels of expression of NMDAR1 and BSI-B4 binding sites in spinal dorsal horn and DRG in rats with adjuvant arthritis.


Assuntos
Analgésicos/farmacologia , Artrite Experimental/tratamento farmacológico , Diterpenos/farmacologia , Gânglios Espinais/efeitos dos fármacos , Dor/tratamento farmacológico , Fenantrenos/farmacologia , Receptores de N-Metil-D-Aspartato/metabolismo , Animais , Artrite Experimental/metabolismo , Sítios de Ligação , Compostos de Epóxi/farmacologia , Adjuvante de Freund , Gânglios Espinais/metabolismo , Injeções Intraperitoneais , Medição da Dor , Ratos , Ratos Sprague-Dawley , Corno Dorsal da Medula Espinal/citologia
5.
Chin J Nat Med ; 11(6): 608-15, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24345501

RESUMO

AIM: To investigate whether diosgenin could modulate tissue factor (TF) procoagulation activity, expression, and related signal transduction pathways. METHODS: Human THP-1 monocytic cells were exposed to tumor necrosis factor-α (TNF-α, 10 ng·mL(-1)) with or without diosgenin (0.01, 0.1, and 1 µmol · L(-1)) for 2 h or 5 h to induce TF procoagulant activity and expression, which were determined by the simplified chromogenic assay, reverse transcription-polymerase chain reaction (RT-PCR), real-time quantitative PCR, and Western blotting assays. In addition, the activation of the NF-κB, Akt, and MAPK signaling pathways were also measured by Western blotting. RESULTS: Diosgenin significantly inhibited TNF-α-induced TF procoagulant activity at concentrations of 0.01 to 1 µmol · L(-1) with IC50 of 0.25 µmol · L(-1). It also reduced protein expression and mRNA accumulation of TF dose-dependently in activated THP-1 cells. TNF-α stimulated significantly phosphorylation on Ser536 of NF-κB/p65, Ser473 of Akt at 5-15 min, and activations of IKK-ß and ERK at 15-30 min. Diosgenin (1 µmol · L(-1)) could inhibit the phosphorylation of NF-κB/p65, IKK-ß, Akt, ERK, and JNK, but had no remarkable effects on IκB and p38 phosphorylation in THP-1 cells. CONCLUSION: Diosgenin inhibits TNF-α-induced TF activity and expression in monocytes, partly due to its down-regulation of the phosphorylation of NF-κB/p65, IKK-ß, Akt, ERK, and JNK.


Assuntos
Diosgenina/farmacologia , Regulação para Baixo/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Monócitos/efeitos dos fármacos , NF-kappa B/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Monócitos/metabolismo , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Fator de Necrose Tumoral alfa/genética
6.
Artigo em Chinês | MEDLINE | ID: mdl-20067003

RESUMO

Freshwater crabs and snails were collected from Ninghai County in Zhejiang Province, and examined respectively for Paragonimus metacercariae and cercariae. Among 97 freshwater crabs found, the prevalence was 11.3% (11/97) with a mean intensity of 1 metacercariae per crab. It was 10.2% (5/49) and 20.2% (4/20) in the groups weighted 5-15 g and 15-25 g respectively, with an average intensity of 1, and no metacercariae were found in weight group of 25-35 g. Two positive crabs were found from 20 crabs with a low weight (< 5 g). Male to female crabs ratio was 2.5:1, and there was no significant difference in prevalence between males [12.7%(7/55)] and females [9.1% (2/22)]. No cercariae or metacercariae were found in 200 snails (Semisulcospira libertino).


Assuntos
Braquiúros/parasitologia , Paragonimíase/epidemiologia , Paragonimus , Caramujos/parasitologia , Animais , China/epidemiologia , Feminino , Água Doce , Interações Hospedeiro-Parasita , Masculino , Paragonimíase/parasitologia
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