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1.
Eur J Pharmacol ; 960: 176178, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37923159

RESUMO

Oxidative stress and inflammation have been implicated in hepatic fibrosis. Antioxidant and anti-inflammatory activities are among the pharmacological effects of hyperoside. This study aimed to evaluate the impact of hyperoside on hepatic fibrosis and elucidate the underlying processes that perpetuate this relationship. The findings indicated that hyperoside significantly protects mouse livers against damage, inflammation, and fibrosis. Specifically, attenuation of hepatic fibrosis is associated with lower expression of HMGB1 protein and reduced expression of Toll-like receptor 4, PARP-1, and nuclear factor-kB (NF-κB) p65 mRNA and protein. Furthermore, hyperoside inhibited the cytoplasmic translocation of HMGB1 and nuclear localization of NF-κB p65 in the hepatic tissues of mice. The results of this study indicate that hyperoside may impose a blocking or reversing effect on hepatic fibrosis; additionally, the corresponding hyperoside-dependent mechanism may be linked to PARP-1-HMGB1 pathway regulation.


Assuntos
Proteína HMGB1 , NF-kappa B , Camundongos , Animais , NF-kappa B/metabolismo , Tetracloreto de Carbono , Proteína HMGB1/genética , Proteína HMGB1/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/tratamento farmacológico , Inflamação , Adenosina Difosfato Ribose
2.
Zhonghua Jie He He Hu Xi Za Zhi ; 45(5): 423-430, 2022 May 12.
Artigo em Chinês | MEDLINE | ID: mdl-35527456

RESUMO

Objectives: To evaluate the reliability and validity of the Chinese version of the test of the adherence to inhalers (TAI) in Chinese patients with chronic airway disease. Methods: Based on the English version of TAI, the items of the Chinese version of TAI were determined after forward-backward translation and cultural adaption. Totally, 165 patients with chronic obstructive pulmonary disease (COPD) and asthma were enrolled from Respiratory Clinic of the Second Xiangya Hospital of Central South University from July to November 2021, and a questionnaire survey was conducted using the Chinese version of TAI and the Morisky medication adherence scale 8-item version (MMAS-8). The content validity of the scale was expressed by content validity index (CVI) and the construct validity was analyzed by exploratory factor analysis (EFA). The convergence validity was evaluated by Pearson correlation analysis. The reliability of the scale was expressed by Cronbach's α coefficient, the split-half reliability and test-retest reliability. Results: The CVI was 0.966. There were 10 items in total. Two factors were extracted from the Chinese version of TAI and the cumulative variance contribution rate was 57.236%. The load value of each item was more than 0.400 and the factor attribution of the item was consistent with the original scale. The total score of the Chinese version of TAI was positively correlated with the total score of the MMAS-8(r=0.835,P<0.001). The Cronbach's α of the overall scale was 0.843, the Guttman's half-reliability coefficient was 0.796 and the test-retest reliability was 0.884 (P<0.001), respectively. Conclusions: The Chinese version of TAI has good reliability and validity, which may be a reliable tool for evaluating the adherence to inhalers of patients with chronic airway disease in China.


Assuntos
Asma , Doença Pulmonar Obstrutiva Crônica , Asma/tratamento farmacológico , China , Humanos , Nebulizadores e Vaporizadores , Psicometria , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Reprodutibilidade dos Testes , Inquéritos e Questionários
3.
Nanoscale Res Lett ; 16(1): 72, 2021 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-33914179

RESUMO

A pressing need in low energy spintronics is two-dimensional (2D) ferromagnets with Curie temperature above the liquid-nitrogen temperature (77 K), and sizeable magnetic anisotropy. We studied Mn3Br8 monolayer which is obtained via inducing Mn vacancy at 1/4 population in MnBr2 monolayer. Such defective configuration is designed to change the coordination structure of the Mn-d5 and achieve ferromagnetism with sizeable magnetic anisotropy energy (MAE). Our calculations show that Mn3Br8 monolayer is a ferromagnetic (FM) half-metal with Curie temperature of 130 K, large MAE of - 2.33 meV per formula unit, and atomic magnetic moment of 13/3µB for the Mn atom. Additionally, Mn3Br8 monolayer maintains to be FM under small biaxial strain, whose Curie temperature under 5% compressive strain is 160 K. Additionally, both biaxial strain and carrier doping make the MAE increases, which mainly contributed by the magneto-crystalline anisotropy energy (MCE). Our designed defective structure of MnBr2 monolayer provides a simple but effective way to achieve ferromagnetism with large MAE in 2D materials.

4.
Phys Chem Chem Phys ; 22(42): 24506-24515, 2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-33089834

RESUMO

Two-dimensional (2D) ferromagnetic (FM) semiconductors are highly desirable in next generation spintronic devices. Herein, we report an intrinsic FM semiconductor, an FeI3 monolayer which can be exfoliated from its bulk crystal owing to the small cleavage energy and the high in-plane stiffness. The FeI3 monolayer is dynamically and mechanically stable. Additionally, the FeI3 monolayer has sizable magneto-crystalline anisotropy energy (MAE) and the Curie temperature is higher than the liquid-nitrogen temperature (77 K), and there is a big discrepancy (Δcbm) between the conduction band minimum of the two spin-channels and negligible thermally induced hop. Carrier doping less than 0.1 e per unit cell further improves the relevant properties by modulating the MAE, Curie temperature, and Δcbm. Moreover, the isoelectronic analogue FeI1.5Cl1.5 monolayer is a bipolar FM semiconductor with a high Curie temperature (260 K). Our results demonstrate promising applications of the FeI3 monolayer in next-generation spintronic devices owing to its robust intrinsic ferromagnetism and novel semiconducting properties.

5.
Zhonghua Yi Xue Za Zhi ; 98(23): 1859-1862, 2018 Jun 19.
Artigo em Chinês | MEDLINE | ID: mdl-29925170

RESUMO

Objective: To research the application of lateral supraorbital (LOS) approach for resecting sellar tumors. Methods: Clinical symptoms of 20 patients with surgery via LOS approach were analyzed retrospectively.According to the neuroradiological findings and the improvement of symptoms, and some score scale, the efficacy and safety of LOS were assessed for removing sellar tumors.There were tuberculum sellae meningioma (n=11), craniopharyngioma (n=4), epidermoid cysts (n=4) and pituitary adenoma (n=1). Results: Complete resection was achieved in seventeen patients(85%). The mean operating time was 144.0±54 minutes and the mean intraoperative blood loss was 96.5±51.1 ml.Four patients had post-operative fever, four had endocrine disorders, and one had seizure.No other complications were noted.Fifteen patients had visual function impairment before operation, seven of which were improved while one was aggravated after surgery.The median Karnofsky score (3-46 mon) was 95(0-100) and the Glasgow outcome scale (GOS) at follow-up (3-46 mon) was 4.7(0-5). In general, the outcomes were improved in 18 patients and the mortality was 2. Conclusion: The resection of tumors at sellar region via lateral supraorbital approach is effecient, simple and minimally invasive, which can make the removal of the tumors reliably and safely.It is worthy to be popularized clinically.


Assuntos
Neoplasias da Base do Crânio , Humanos , Neoplasias Meníngeas , Meningioma , Procedimentos Neurocirúrgicos , Neoplasias Hipofisárias , Estudos Retrospectivos , Resultado do Tratamento
6.
Zhonghua Liu Xing Bing Xue Za Zhi ; 39(1): 63-66, 2018 Jan 10.
Artigo em Chinês | MEDLINE | ID: mdl-29374898

RESUMO

Objective: To understand the circulation, drug resistance and molecular characteristics of Salmonella1, 4, [5], 12: i:- in human in Guangdong province. Methods:Salmonella1, 4, [5], 12: i:- isolated from diarrhea patients in Guangdong during 2007-2016 were detected for drug resistance, genes and PFGE characteristics. Results: A total of 2 960 strains Salmonella1, 4, [5], 12: i: - were isolated from human diarrhea cases during this period. The positive rates of the isolation increased year by year. The male to female ratio of the infection cases was 1.58∶1, and the infection mainly occurred in infants and young children. Except imipenem, Salmonella1, 4, [5], 12: i: - was resistant to other 17 antibiotics to some extent. The drug resistant rates to ceftazidime, cefotaxime and ciprofloxacin increased from 2011 to 2016. Multi-drug resistance was serious, for example, the multi-drug resistant strains with ASSuT accounted for 70.62% (435/616) and the multi-drug resistant strains with ACSuGSTTm accounted for 27.11% (167/616). The lack of fljA, fljB and hin genes, as well as the retaining of iroB, STM2740, STM2757 genes, resulted in the unable expression of FljBenx gene with 8 different defection profiles. There were 934 different PFGE patterns observed in 2 347 strains, which displayed a relatively large fingerprint polymorphism. The major PFGE pattern was JPXX01. GD0226, which was found in 97 strains, accounting for 4.13% (97/2 347). The PFGE patterns in 168 Salmonella1, 4, [5], 12: i: - strains were consistent with that of Salmonella typhimurium. Conclusions:Salmonella1,4,[5], 12: i: - strains has become the major serotype of Salmonella that cause diarrhea in human in Guangdong. The multi-drug resistance of Salmonella1,4, [5], 12: i: - was serious, and since the defection of fljA, fljB and hin genes, the expression of FljBenx protein failed. The PFGE results were diverse, which displayed polymorphism in inheritance.


Assuntos
Antibacterianos/farmacologia , Diarreia/microbiologia , Infecções por Salmonella/microbiologia , Infecções por Salmonella/prevenção & controle , Salmonella enterica/efeitos dos fármacos , Salmonella enterica/isolamento & purificação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , China/epidemiologia , Diarreia/epidemiologia , Farmacorresistência Bacteriana , Eletroforese em Gel de Campo Pulsado , Feminino , Humanos , Lactente , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Infecções por Salmonella/diagnóstico , Infecções por Salmonella/epidemiologia , Salmonella enterica/genética , Salmonella typhimurium , Sorogrupo , Sorotipagem , Adulto Jovem
7.
Zhonghua Jie He He Hu Xi Za Zhi ; 39(11): 866-870, 2016 Nov 12.
Artigo em Chinês | MEDLINE | ID: mdl-27852363

RESUMO

Objective: To analyze the clinical features of one case of spontaneous hemothorax caused by primary pleural chondrosarcoma and therefore to improve the understanding of this disease. Methods: The clinical features of a case with primary pleural chondrosarcoma were analyzed retrospectively and the related literatures were reviewed.The literature review was carried out with "primary pleural, chondrosarcoma" in Chinese and English respectively, as the search terms in Wanfang Data, CNKI and PubMed database from January 1980 to October 2015. A total of 6 articales, 1 in Chinese and 5 in English, were reviewed. Results: A 29 year-old male patient was admitted to the hospital because of fever, chest tightness, shortness of breath for 20 days. CT scan of the chest showed a mass near the right posterior fourth rib and right pleural effusion.Routine examination of the pleural effusion confirmed the presence of hemothorax. Thoracotomy was performed and revealed hemothorax in the right thorax, and a mass near the pleural apex. The tumor was removed by surgery and pleural decortication was also performed. Pathology study confirmed the diagnosis of high-differentiated chondrosarcoma. The patient was followed and there was no recurrence until now. A total of 6 case reports were retrieved from Wanfang Data, CNKI and PubMed. Five cases had complete data, including 2 males and 3 females(age from 28 to70), and another (a 78-year old male) without adequate data. Conclusions: Primary pleural chondrosarcoma is a rare disease, and hemothorax as the first manifestation is even rare. It is easily to be misdiagnosed due to nonspecific clinical symptoms.The final diagnosis depends ultimately on pathological biopsy. Thoracotomy is the most effective method for treatment of primary pleural chondrosarcoma.


Assuntos
Neoplasias Ósseas/complicações , Condrossarcoma/complicações , Hemotórax/etiologia , Adulto , Biópsia , Neoplasias Ósseas/patologia , Neoplasias Ósseas/cirurgia , Condrossarcoma/patologia , Condrossarcoma/cirurgia , Erros de Diagnóstico , Febre/etiologia , Hemotórax/diagnóstico por imagem , Hemotórax/cirurgia , Humanos , Masculino , Recidiva Local de Neoplasia , Pleura/patologia , Derrame Pleural/diagnóstico por imagem , Toracotomia , Tórax , Tomografia Computadorizada por Raios X
8.
Zhonghua Liu Xing Bing Xue Za Zhi ; 37(10): 1373-1378, 2016 Oct 10.
Artigo em Chinês | MEDLINE | ID: mdl-27765129

RESUMO

Objective: To study the infection status, serotypes, drug resistance and molecular characteristics of Salmonella, Shigella, Vibrio parahemolyticus, enterotoxigenic Escherichia (E.) coli (ETEC), pathogenic E. coli (EPEC), Shiga Toxin producing E. coli (STEC) and Enteroinvasive E. coli (EIEC) collected from diarrhea patients in Guangdong. Methods: The strains of Salmonella, Shigella, V. parahemolyticus and 4 kinds of E. coli isolated from foodborne diseases surveillance during 2013-2014 were collected to conduct serotyping, drug resistance test and pulsed-field gel electrophoresis (PFGE). Results: A total of 3 372 stains of pathogens were isolated from 57 834 stool samples during 2013-2014, the overall positive rate was 5.83% and the positive rate of Salmonella was highest, followed by that of V. parahemolyticus, 4 kinds of E. coli and Shigella. And 3 213 strains of Salmonella were divided into 143 serotypes. The most prevalent serotypes were Salmonella typhimurium, 4, 5, 12: i:-, Enteritidis, Stanley and Derby. Salmonella was sensitive to cephalosporin and fluoroquinolones, and showed significant differences in drug resistance rate among different serotypes. In top 10 common serotypes, S. enteritidis and S. derby were most resistant to cephalosporin and ciprofloxacin respectively. PFGE was performed for 2 289 strains of Salmonella, showing distribution diversity and significant fingerprint polymorphisms. The 85 strains of V. parahemolyticus were divided into 10 serotypes, O3∶K6 (61.18%) was the most common serotype, followed by O4∶K8. The results showed that the carrying rate of virulence genes tdh (81.18%) was high, while the carrying rate of trh was low (7.06%), and there were 10 strains carrying no the two kinds of virulence genes. The sensitive rate of V. parahemolyticus to imipenem, nalidixic acid, SMZ-TMP, chloramphenicol and tetracycline were more than 95%. Thirteen strains of Shigella were detected, including 9 strains of Shigella sonnei, 3 strains of Shigella flexneri and 1 strains of Shigella bogdii. The strains all showed sensitivity to ceftazidime, ciprofloxacin and chloramphenicol (76.92%). There were 86 strains of E. coli detected, including 29 strains of ETEC (33.72%), 27 strains of EPEC (31.39%), 27 strains of STEC (31.39%) and 3 strains of EIEC (3.48%). Conclusions: In the active etiological surveillance for foodborne diseases in Guangdong during 2013-2014, the detection rate of Salmonella was highest (5.57% ), followed by that of V. parahemolyticus, 4 kinds of E. coli and Shigella. Salmonella, V. parahemolyticus and Shigella were sensitive to cephalosporin and fluoroquinolones. Clustered cases of Salmonella infection were found in the surveillance, but no outbreaks occurred.


Assuntos
Escherichia coli , Doenças Transmitidas por Alimentos/etiologia , Salmonella typhimurium , Shigella , Vibrio parahaemolyticus , Antibacterianos , China/epidemiologia , Diarreia , Eletroforese em Gel de Campo Pulsado , Infecções por Escherichia coli , Doenças Transmitidas por Alimentos/epidemiologia , Humanos , Infecções por Salmonella , Sorotipagem , Virulência
9.
Zhonghua Liu Xing Bing Xue Za Zhi ; 37(8): 1137-41, 2016 Aug 10.
Artigo em Chinês | MEDLINE | ID: mdl-27539348

RESUMO

OBJECTIVE: To understand the effect of serotyping on Salmonella isolates, by use of Microsphere-based Liquid Array method, among diarrhea patients, in Guangdong. METHODS: Salmonella isolated from humans in Guangdong province were serotyped on the Microsphere-based Liquid Array platform with SSA kit. RESULTS: A total of 4 942 Salmonella strains with 189 serotypes, were identified in Guangdong province in 2010-2014. The top 100 serotypes accounted for 98.08% (4 847/4 942) of all the strains. 98% of the top 100 species serotypes could completely be serotyped with SSA kit. In order to detect O antigen among 198 isolates with SSA kit, 181 strains were carrying the O antigen, with the coincidence rate as 100%. However, under the SSA, 98.32% (528/537) of the H antigen could be detected and were consistent with the traditional serum agglutination test. The coincidence rate of fljB gene was 93.09% (175/188), with false negative rate and false positive rate of fljB gene as 7.35% (9/134) and 7.41% (4/54) respectively. The coincidence rate of sdf gene and Vi gene were 100%. 11 out of the 12 Salmonella strains could not be serotyped under the traditional methods but were successfully serotyped by the molecular serotyping method. CONCLUSIONS: Using the SSA kit, more than 96% of the anthropogenic Salmonella strains could be serotyped in Guangdong province. Comparing with the traditional methods, the coincidence rate of serotyping appeared over 98% . Under the Microsphere-based Liquid Array techniques, the molecular serotyping method appeared faster and more accurate on Salmonella serotyping than those traditional methods.


Assuntos
Antígenos de Bactérias/genética , Técnicas de Tipagem Bacteriana/métodos , Diarreia/microbiologia , Microesferas , Salmonella/classificação , Salmonella/isolamento & purificação , Testes de Aglutinação , Humanos , Análise em Microsséries , Antígenos O , Salmonella/genética , Infecções por Salmonella , Sorotipagem
10.
Eur Rev Med Pharmacol Sci ; 18(10): 1487-95, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24899607

RESUMO

BACKGROUND: Despite progress of medical, the fast and accurate diagnosis of tuberculous pleuritis (TP) continues to be a challenge, mainly because of the lack of specific clinical features and the difficulty in isolating the Mycobacterium tuberculosis. OBJECTIVES: To investigate the role of medical thoracoscopy in definite diagnosis of tuberculous pleuritis, especially the feature of visual diagnosis in tuberculous pleuritis via medical thoracoscopy. We performed a retrospective review of the utility of medical thoracoscopy in tuberculous pleuritis. PATIENTS AND METHODS: A retrospective chart review was performed of 91 patients who had medical thoracoscopy for suspected TP at the Second Xiangya Hospital from October 1, 2006 to July 30, 2012. RESULTS: In ninety one cases, 76 patients were diagnosed with TP by pathologic diagnosis. The visual findings via thoracoscopy of 76 TP patients included the following: (1) necrosis (76.32%, n=58), (2) diffuse miliary nodules (64.67%, n=49), (3) single or multiple pleural nodules (14.47%, n=11), (4) hyperemic, edematous and thickened pleura (56.58%, n=43), and (5) pleural adhesions or fibrotic septa (78.95%, n=60), and all of these samples had hydrothorax or loculated effusion. The diagnostic efficiency of visual diagnosis via medical thoracoscopy about tuberculous pleuritis was 93.41%. In the non-invasive test, ADA > 40 u/l with LDH > 200 u/l for TP showed relatively high sensitivity and specificity (73.68%, 80.00%, respectively). CONCLUSIONS: TP presents a variety of scopic phenotypes under medical thoracoscopy. The experienced pulmonologists visually diagnose TP efficiently and directly via medical thoracoscopy. Medical thoracoscopy with combined biopsy is an accurate and safe method for diagnosing TP.


Assuntos
Toracoscopia/estatística & dados numéricos , Tuberculose Pleural/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Adulto Jovem
11.
Med Chem ; 6(5): 286-97, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20977412

RESUMO

Thioredoxin reductase plays a critical role in the regulation of cancer cell apoptosis, making it an attractive target for the design of new anticancer drugs. Several classes of compounds have been considered as potential antitumor or chemopreventive agents; most of them apparently interact with thioredoxin reductase's C-terminal redox center.


Assuntos
Antineoplásicos/farmacologia , Inibidores Enzimáticos/farmacologia , Terapia de Alvo Molecular , Neoplasias/tratamento farmacológico , Tiorredoxina Dissulfeto Redutase/antagonistas & inibidores , Tiorredoxina Dissulfeto Redutase/metabolismo , Antineoplásicos/metabolismo , Apoptose , Inibidores Enzimáticos/metabolismo , Humanos , Neoplasias/enzimologia , Oxirredução
12.
Tissue Cell ; 41(2): 133-40, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19019400

RESUMO

In the pituitary gland, NO is locally synthesized by gonadotroph and folliculo-stellate cells. Many reports have shown that NO can modulate the growth hormone (GH) secretion. However, its role on mice embryo GH regulation remains unclear. In addition, it is unknown whether the regulation is associated with the proliferation of pituitary cells. In this study, we have investigated the regulatory effects of NO on somatotroph differentiation, proliferation and GH mRNA and protein expression using primary cell cultures of mice fetal pituitaries (embryonic days 16.5, ED 16.5). Our results show that incubation of pituitary cells in the presence of sodium nitroprusside (SNP; 1mM), a NO donor, for 4.5h resulted in a significant increase in GH mRNA and protein expression (P<0.05) and the stimulation of SNP can be inhibited by hemoglobin, a NO scavenger. But the addition of cyclic guanosine monophosphate (cGMP; 3.0mM), the second messenger of multiple NO actions cannot influence GH mRNA and protein expression. The cyclic nucleotide cellular efflux pumps existed in the pituitary cells can transport the majority of de novo-produced cGMP and effectively block cGMP accumulation. For maintaining intracellular concentration of cGMP, probenecid (0.5mM), a blocker of cGMP efflux pump, combined with cGMP (3.0mM) was used to treat the pituitary cells. This also cannot influence GH mRNA and protein expression. In addition, the ratio of GH-positive cells is increased significantly after the stimulation of SNP (P<0.05). However, SNP cannot modulate the pituitary cell proliferation. From these results we conclude that NO can increase GH mRNA and protein expression in fetal pituitary cells and cGMP is not involved in this hormonal regulation. Stimulation of NO on the somatotroph differentiation does not occur due to pituitary cell proliferation.


Assuntos
Diferenciação Celular/fisiologia , GMP Cíclico/metabolismo , Hormônio do Crescimento/metabolismo , Óxido Nítrico/fisiologia , Proteínas/metabolismo , RNA Mensageiro/metabolismo , Adjuvantes Farmacêuticos/farmacologia , Animais , Técnicas de Cultura de Células , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Células Cultivadas , Meios de Cultura Livres de Soro , GMP Cíclico/genética , Embrião de Mamíferos/metabolismo , Hormônio do Crescimento/genética , Óxido Nítrico/genética , Doadores de Óxido Nítrico/farmacologia , Nitroprussiato/farmacologia , Hipófise/citologia , Hipófise/embriologia , Hipófise/metabolismo , Probenecid/farmacologia , Fatores de Tempo
13.
Acta Pharmacol Sin ; 22(12): 1094-8, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11749806

RESUMO

AIM: To investigate the inhibition capacities of carnosol, rosmanol, and epirosmanol, which are phenolic diterpenes from Rosmarinus officinalis, to oxidized low-density lipoprotein (LDL) formation in human blood and detect their scavenging activities to lipid free radical and superoxide anion in vitro. METHODS: The antioxidant activities which were expressed with the inhibilities to lipid free radicals in the membrane lipid of cell and oxidized LDL formation were evaluated by TBARS assay and ESR method. The inhibition on the Cu2+-mediated oxidization of apo B formation in LDL was investigated by fluorescence spectroscopy. RESULTS: Carnosol, rosmanol, and epirosmanol had an inhibitory activity to lipid peroxidation and oxidized apo B formation in human bloods LDL. The IC50 were 7-10 micromol/L. The antioxidant mechanism was related to the scavenging activities to lipid free radical. CONCLUSION: carnosol, rosmanol, and epirosmanol showed the activity in inhibiting LDL oxidation.


Assuntos
Antioxidantes/farmacologia , Diterpenos/farmacologia , Lipoproteínas LDL/metabolismo , Fenantrenos/farmacologia , Rosmarinus/química , Abietanos , Membrana Celular/efeitos dos fármacos , Radicais Livres/metabolismo , Humanos , Hidroxibenzoatos/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Superóxidos/metabolismo
14.
Oncogene ; 19(39): 4476-9, 2000 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-11002420

RESUMO

We tested the cytotoxic action of 8-hydroxyguanine (8ohG) by observing the viability of several leukemic cell lines (KG-1, U937, Jurkat and K 562) in the presence of 8-hydroxydeoxyguanosine (8ohdG), a nucleoside of 8ohG. It was found that 8ohdG showed cytotoxic action only to KG-1 and that only KG-1 showed a homozygous arginine 209 to glutamine mutation in the hOGG1 gene with an almost negligible hOGG1 enzyme activity. Possibly, the selective cytotoxicity in 8ohdG to KG-1 may be due to its low capacity to cope with an increase in the 8ohG level in DNA resulting from the incorporation of 8ohdG present in the culture media. The mutational impairment of hOGG1 in KG-1 is the first report in leukemic cell lines. Using KG-1 with impaired hOGG1, we demonstrated cytotoxicity of 8ohdG probably due to its incorporation into cellular DNA. This new property of KG-1 may allow it to serve as an useful tool for studies of OGG1, oxidative DNA damage and the cytotoxic action of 8ohG. Oncogene (2000) 19, 4476 - 4479.


Assuntos
Desoxiguanosina/análogos & derivados , Leucemia/genética , N-Glicosil Hidrolases/genética , Mutação Puntual , 8-Hidroxi-2'-Desoxiguanosina , Morte Celular/efeitos dos fármacos , Morte Celular/genética , DNA-Formamidopirimidina Glicosilase , Desoxiguanosina/farmacologia , Humanos , Leucemia/tratamento farmacológico , N-Glicosil Hidrolases/efeitos dos fármacos , Células Tumorais Cultivadas
15.
J Biomed Opt ; 5(1): 17-22, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10938761

RESUMO

Previously, we had shown that the zinc-dependent binding of certain fluorescent aryl sulfonamide inhibitors could be used with apocarbonic anhydrase II to transduce the level of free zinc as a change in the fluorescence of the inhibitor. While inhibitors such as dansylamide, ABD-M, and ABD-N made possible quantitation of free zinc in the picomolar range with high selectivity, they have only modest absorbance which limits their utility. We describe here the synthesis and properties of two new probes, Dapoxyl sulfonamide and BTCS, and their use in zinc biosensing. Dapoxyl sulfonamide exhibits a dramatic increase and blue shift in its emission upon binding to holocarbonic anhydrase II, as well as a 20-fold increase in lifetime: it is thus well suited for quantitating free Zn(II) down to picomolar ranges. The anisotropy of BTCS increases fivefold upon binding to the holoprotein, making this probe well suited for anisotropy-based determination of zinc. BTCS and ABD-N are efficiently excited with two photon excitation using 1.5 ps pulses from a titanium sapphire laser, and exhibit the increased zinc-dependent anisotropy response anticipated on the basis of photoselection.


Assuntos
Anidrases Carbônicas/química , Corantes Fluorescentes/química , Espectrometria de Fluorescência , Zinco/análise , Anisotropia , Benzotiazóis , Cumarínicos/síntese química , Cumarínicos/química , Corantes Fluorescentes/síntese química , Humanos , Oxazóis/síntese química , Oxazóis/química , Sulfonamidas/síntese química , Sulfonamidas/química , Tiazóis/síntese química , Tiazóis/química
16.
Int J Biol Macromol ; 20(2): 107-13, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9184942

RESUMO

The conformation change of G-actin of F-actin and the binding modes of cisplatin and transplatin to F-actin have been studied by FT-Raman spectroscopy. The studies show that the process of polymerization is related to the vibration of C-S Gauche mode (approximately 650 cm-1), which indicates that the methionine (Met) contributes to the polymerization of actin. The relative intensity of I(925)/I(803), reflecting the conformation of actin secondary structure, does not change during the polymerization process. The effect of cisplatin and transplatin on F-actin is dependent on the species and their concentrations. Cisplatin, at high concentrations, affects the conformation of F-actin mainly by binding with the sulphur of methionine. Transplatin, even at low concentrations, obviously affects the F-actin's conformation due to it's multiple binding sites, on N-containing sites in addition to S-methionine sites. These results relate to the differences in pharmacology and toxicology effects of the complexes.


Assuntos
Actinas/química , Actinas/metabolismo , Antineoplásicos/metabolismo , Cisplatino/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Sítios de Ligação , Biopolímeros/química , Biopolímeros/metabolismo , Técnicas In Vitro , Substâncias Macromoleculares , Metionina/química , Ligação Proteica , Conformação Proteica , Estrutura Secundária de Proteína , Coelhos , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
17.
Int J Biol Macromol ; 18(3): 161-6, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8729027

RESUMO

The microcalorimetic measurement for studying the thermokinetic of actin polymerization in vitro was employed for the first time. The thermodynamic parameters of actin polymerization at 310.15 K are reported as delta Hm = 49.26 kJ/mol, delta Gm = 25.62 kJ/mol and delta Sm = 241.54 J/K.mol. The thermogram shows that polymerization of actin is a complicate process in which multistep reactions occur corresponding to exothermic and endothermic effects. Cisplatin, at lower concentration, affects the polymerization of G-actin resulting in a decrease of delta Hm; and, at higher concentration, induce the crosslinking and depolymerization of F-actin in the equilibrium system of G/F. The experimental results show that as the concentration of cisplatin increases, the sign of delta Hm changes from positive to negative, i.e. the magnitude and sign of delta Hm of actin polymerization depends on the concentration of cisplatin.


Assuntos
Actinas/química , Cisplatino/farmacologia , Actinas/efeitos dos fármacos , Trifosfato de Adenosina/farmacologia , Biopolímeros , Calorimetria , Fenômenos Químicos , Físico-Química , Depressão Química , Temperatura Alta , Cinética , Microquímica , Termodinâmica
18.
Cell Biol Int ; 19(6): 491-7, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7640663

RESUMO

The effects of cisplatin and transplatin on the conformation and association of F-actin were studied by ESR, turbidimetry and CD measurement. The results indicate that the major component affecting F-actin secondary conformation is derived from their effect on the tertiary or quaternary conformation and association states of F-actin. The effect of platinum is seen by the fact that binding of cisplatin causes first an increase in molecular size followed by a later decrease. The induction time for the association depended on the concentration of cisplatin. Transplatin was able to reach the target site more readily, resulting in the dissociation of F-actin even at a very low concentration.


Assuntos
Actinas/química , Cisplatino/farmacologia , Conformação Proteica/efeitos dos fármacos , Animais , Coelhos
19.
Talanta ; 41(6): 969-75, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18966024

RESUMO

A new type of optode membrane for the determination of alcohols, such as methanol, ethanol, propan-1-ol and propan-2-ol etc, is presented that can be exploited in optical and fibre-optic sensors. It is based on the use of a new lipophilic fluorescent reagent, namely fluorescein octadecyl ester (FODE), which is immobilized in a plasticized PVC membrane. The response mechanism relies on the fact that FODE can reversibly recognize alcohol molecules due to the hydrogen bonding formation between FODE and alcohol molecules. The analytical information in this membrane is the enhancement of the relative fluorescence intensity measured at 527 nm (463 nm, excitation). Under the optimum condition, the membrane has a wide measuring range for alcohol samples. The membrane has been applied to determine the concentration of ethanol in alcoholic drinks with satisfactory results.

20.
Talanta ; 40(10): 1569-73, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18965822

RESUMO

Pyrene immobilized in plasticized poly(vinyl chloride) (PVC) membrane is able to extract selectively picric acid from the sample solution into the organic membrane phase. Since this extraction equilibrium is accompanied by a change in the fluorescence spectrum of pyrene, the chemical recognition process can be directly translated into an optical signal. With the optode membrane described, picric acid in sample solutions from 8.7 x 10(-6) to 4.3 x 10(-3)M can be determined. The calibration curve of the optode membrane for picric acid shows a good correlation with the mathematically derived formalism and thus confirms the theoretically expected behaviour. Besides a high reproducibility of the optical signals, the very short response times less than 35 sec are realized. The optode membrane presented exhibits good selectivity for picric acid over many other usual hydrophobic anions.

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