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1.
Cardiology ; 141(1): 9-17, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30293082

RESUMO

BACKGROUND: Autoantibody against M2-muscarinic acetylcholine receptor (anti-M2AChR) has a biological effect similar to a vagus agonist. Digoxin has a function of vagus nervous system stimulation. We hypothesized that anti-M2AChR is highly correlated with digoxin in patients with chronic heart failure (CHF). METHODS: Synthetic M2AChR peptides served as the target antigen in an ELISA were used to screen the sera of 80 CHF patients, who were separated into a negative (-) or positive (+) anti-M2AChR group according to their anti-M2AChR reactivity. Echocardiography and serum digoxin concentration (SDC) were performed at baseline and after 1 year of digoxin in combination with the standard treatment regime. The end-point events were compared over 1 year of follow-up. RESULTS: Seventy-two CHF patients completed the final data analysis, including 32 (+)anti-M2AChR and 40 (-)anti-M2AChR patients. The resting heart rate of the positive group was higher than that of the negative group at baseline (p < 0.05; 89.0 ± 1.6 vs. 83.8 ± 1.1 bpm). Both groups showed improvement in the left ventricular end-diastolic and end-systolic dimensions and ejection fraction with digoxin in combination with the standard treatment regime for 1 year (all p < 0.01). However, the 32 patients with (-)anti-M2AChR had greater improvements than the 40 patients with (+)anti-M2AChR, and this was accompanied by a marked decrease of rehospitalization (all p < 0.01) but not of cardiovascular mortality after 1 year. The SDC of patients with (-)anti-M2AChR was significantly lower than that of patients with (+)anti-M2AChR (p < 0.05; 0.63 ± 0.05 vs.1.16 ± 0.06 ng/mL) and had a positive correlation with anti-M2AChR (r = 0.81, p < 0.001). CONCLUSION: These results suggested that anti-M2AChR could be a useful biomarker of vagus nerve overactivation and is associated with a poor response to digoxin treatment in CHF patients.


Assuntos
Cardiotônicos/sangue , Digoxina/sangue , Receptor Muscarínico M2/sangue , Função Ventricular Esquerda/efeitos dos fármacos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Autoanticorpos , Biomarcadores/sangue , Cardiotônicos/uso terapêutico , China , Digoxina/uso terapêutico , Ensaio de Imunoadsorção Enzimática , Teste de Esforço , Feminino , Insuficiência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
2.
Chemphyschem ; 13(5): 1232-9, 2012 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-22302701

RESUMO

Drying-tube-shaped single-walled carbon nanotubes (SWCNTs) with multiple carbon ad-dimer (CD) defects are obtained from armchair (n,n,m) SWCNTs (n=4, 5, 6, 7, 8; m=7, 13). According to the isolated-pentagon rule (IPR) the drying-tube-shaped SWCNTs are unstable non-IPR species, and their hydrogenated, fluorinated, and chlorinated derivatives are investigated. Interestingly, chemisorptions of hydrogen, fluorine, and chlorine atoms on the drying tube-shaped SWCNTs are exothermic processes. Compared to the reaction energies for binding of H, F, and Cl atoms to perfect and Stone-Wales-defective armchair (5,5) nanotubes, binding of F with the multiply CD defective SWCNTs is stronger than with perfect and Stone-Wales-defective nanotubes. The reaction energy for per F(2) addition is between 85 and 88 kcal mol(-1) more negative than that per H(2) addition. Electronic structure analysis of their energy gaps shows that the CD defects have a tendency to decrease the energy gap from 1.98-2.52 to 0.80-1.17 eV. After hydrogenation, fluorination, and chlorination, the energy gaps of the drying-tube-shaped SWCNTs with multiple CD defects are substantially increased to 1.65-3.85 eV. Furthermore, analyses of thermodynamic stability and nucleus-independent chemical shifts (NICS) are performed to analyze the stability of these molecules.

3.
J Geriatr Cardiol ; 19(5): 335-342, 2022 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-35722031

RESUMO

BACKGROUND: There is scarce data on the long-term mortality and associated prognostic factors in patients with dilated cardiomyopathy (DCM). The study aimed to investigate the all-cause mortality up to 15 years (mean 7.9 ± 5.7 years) in such patients, and the independent prognostic factors influencing their long-term mortality. METHODS: One hundred and sixty-six consecutive patients with DCM were prospectively enrolled from 2002 to 2003. The mean age of patients was 59.5 ± 10.4 years, and approximately 57% were male. They were followed up by telephone or outpatient visit at least every three months until 2019 or all-cause death occurred. Predictors of mortality were identified using multivariate logistic regression analysis. RESULTS: During the 15 years of follow-up, five patients were lost to follow-up, and the complete data records of 161 patients were included in the analysis. Patients were treated with angiotensin-converting-enzyme inhibitors (ACEI) or angiotensin-receptor blocker (ARB), ß-blockers, mineralocorticoid receptor antagonist (MRA), diuretics and digitalis from 2002 to 2004, and maintained at the maximum tolerated doses between 2004 and 2019. Our safety targets to maintain heart rate and blood pressure at 60-80 beats/min and 90-120/60-80 mmHg, respectively. All-cause mortality in the first five years was 55.9%. The independent risk factors for the 5-year mortality were age ≥ 70 years old (OR = 5.45, P = 0.006), systolic blood pressure (SBP) > 120 mmHg (OR = 3.63, P = 0.004), 6-minute walk distance (6MWD) < 450 m (OR = 3.84, P = 0.001). 15-year all-cause mortality was 65.8%. The independent risk factors for 15-year mortality were age ≥ 70 years old (OR = 16.07, P = 0.009), LVEF ≤ 35% (OR = 5.69, P = 0.003), and SBP > 120 mmHg (OR = 9.56, P < 0.001). CONCLUSIONS: This study was the first to demonstrate the 15-year survival rate of 34% in DCM patients. The DCM patients' first five-year all-cause mortality decreased significantly after continuous standardized treatment and intensive management. The mortality then plateaued in the following 10 years. Age ≥ 70 years, LVEF ≤ 35%, and SBP > 120 mmHg were independent predictors of 15-year all-cause mortality.

4.
ACS Nano ; 15(9): 14253-14262, 2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34409836

RESUMO

As a powerful signal amplification tool, the DNA walker has been widely applied to detect rare microRNA (miRNA) in vivo. Despite the significant advances, a near-infrared (NIR) light controllable DNA walker for signal amplification powered by an endogenous initiator has not been realized, which is crucial for spatiotemporal imaging of miRNA in living cells with high sensitivity. Herein, we constructed a NIR-photoactivatable DNA walker system, which was powered by endogenous adenosine triphosphate (ATP) for in situ miRNA imaging with spatial and temporal resolution. The system was very stable with an extremely low fluorescent background for the bioimaging in living cells. We employed upconversion nanoparticles (UCNPs) as the carriers of the DNA probe and transducers of converting NIR to UV light. Coupled with the DNA walker fueled by intracellular ATP, a smart system based on the NIR light initiated DNA walker was successfully developed for precise spatiotemporal control in living cells. Triggered by NIR light, the DNA walker could autonomously and progressively travel along the track with the assistance of intracellular ATP. The system has been successfully applied for in situ miRNA imaging in different cell lines with highly spatial and temporal resolution. This strategy can expand NIR photocontrol the DNA walker for precise imaging in a biological system.


Assuntos
Trifosfato de Adenosina , MicroRNAs , DNA/genética , MicroRNAs/genética
5.
Am J Physiol Gastrointest Liver Physiol ; 299(6): G1231-40, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20864656

RESUMO

Stretch sensitivity of Ca²(+)-activated large-conductance K(+) channels (BK(Ca)) has been observed in a variety of cell types and considered to be a potential mechanism in mechanoelectric transduction (MET). Mechanical stress is a major stimulator for the smooth muscle in the gastrointestinal (GI) tract. However, much about the role and mechanism of MET in GI smooth muscles remains unknown. The BK(Ca) shows a functional diversity due to intensive Slo I alternative splicing and different α/ß-subunit assembly in various cells. The stress-regulated exon (STREX) insert is suggested to be an indispensable domain for the mechanosensitivity of BK(Ca). The purpose of this study was to determine whether the BK(Ca) in colonic myocytes of the adult mouse is sensitive to mechanical stimulation and whether the STREX insert is a crucial segment for the BK(Ca) mechanosensitivity. The α- and ß1-subunit mRNAs and the α-subunit protein of the BK(Ca) channels were detected in the colonic muscularis. We found that the BK(Ca) STREX-lacking variant was abundantly expressed in the smooth muscle, whereas the STREX variant was not detectable. We demonstrated that the STREX-lacking BK(Ca) channels were also sensitive to membrane stretch. We suggest that in addition to the STREX domain, there are other additional structures in the channel responsible for mechanically coupling with the cell membrane.


Assuntos
Colo/anatomia & histologia , Canais de Potássio Ativados por Cálcio de Condutância Alta/metabolismo , Mecanotransdução Celular/fisiologia , Músculo Liso/fisiologia , Potenciais de Ação , Animais , Células 3T3 BALB , Cálcio/metabolismo , Cálcio/farmacologia , Colo/fisiologia , Éxons , Feminino , Variação Genética , Ativação do Canal Iônico/fisiologia , Canais de Potássio Ativados por Cálcio de Condutância Alta/genética , Masculino , Camundongos , Contração Muscular , Miócitos de Músculo Liso/fisiologia , Técnicas de Patch-Clamp , Isoformas de Proteínas , Subunidades Proteicas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
6.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 3): m287, 2010 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-21580232

RESUMO

In the structure of the title compound, 2[Ag(C(10)H(8)N(2))(H(2)O)](C(7)H(6)NO(2))(NO(3))·H(2)O, the Ag(I) atom is three-coordinated in a T-shaped configuration by two N atoms from two symmetry-related 4,4'-bipyridine (bipy) ligands at short distances and by one water O atom at a longer distance. Each bipy ligand bridges two neighbouring Ag(I) atoms, forming a chain structure extending parallel to [101]. The complete 4-amino-benzoate anion, the nitrate anion and the uncoordinated water mol-ecule are located on mirror planes: together with the coordinated water mol-ecule, they form N-H⋯O, O-H⋯O and O-H⋯N hydrogen bonds, stabilizing the crystal structure.

7.
Exp Ther Med ; 19(2): 1259-1266, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32010297

RESUMO

A number of studies have suggested that autoantibodies against ß1-adrenoreceptors (ß1R-AAbs) have an important role in pathophysiological processes of heart failure. The aim of the present study was to determine whether ß1R-AAbs are implicated in cardiac dysfunction following acute myocardial infarction (AMI) and their association with prognosis. A total of 33 cases with systolic heart failure (SHF), 49 with diastolic heart failure (DHF) and 44 with normal heart function following AMI were recruited. ß1R-AAbs were detected by ELISA and major adverse cardiac events (MACEs) were recorded during the 5-year follow-up. The positive rate of ß1R-AAbs in the SHF group (45.5%) was significantly higher compared with that in the DHF (22.4%; P<0.05) and normal (15.9%; P<0.05) groups. The area under the receiver operating characteristics curve for the diagnosis of SHF was 0.630 (95% CI: 0.514-0.747, P=0.026). During a median follow-up period of 51.0±15.4 months, the positive rate of ß1R-AAbs in the MACEs group was significantly higher compared with that in the non-MACEs group (P<0.05). Multivariate logistic regression analysis indicated that the left ventricular ejection fraction and diabetes were independent predictors of 5-year MACEs following AMI, whereas ß1R-AAbs were not. Kaplan-Meier analysis revealed that the cumulative MACEs-free survival rate was the lowest in the SHF group, followed by the DHF and normal groups (P<0.05). Therefore, ß1R-AAbs were indicated to be of value for early diagnosis of SHF after AMI but not as independent predictors for the prognosis of patients with AMI.

8.
J Geriatr Cardiol ; 17(6): 305-312, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32670360

RESUMO

OBJECTIVE: To determine the possible association of anti-ß1-adrenergic receptors (anti-ß1-AR), anti-ß2-AR and anti-α1-AR with carvedilol treatment in patients with heart failure (HF). METHODS: A total of 267 HF patients were prospectively enrolled. Blood samples were measured by an enzyme-linked immunosorbent assay. All of the patients received carvedilol for their HF. Each patient was followed up for six months and their cardiac function was measured. RESULTS: The final analysis encompassed 137 patients comprising 65 patients with three autoantibodies (positive group) and 72 patients without all three autoantibodies but with one or two autoantibodies (negative group). The frequency and geometric mean titer of anti-ß1-AR, anti-ß2-AR, and anti-α1-AR were significantly lower in the group without all three autoantibodies after six months of carvedilol treatment (all P < 0.01; from 100% to 57%, 50%, and 49%, respectively; and from 1: 118, 1: 138, and 1: 130 to 1: 72, 1: 61, and 1: 67, respectively). Furthermore, 28 patients in the positive group demonstrated complete ablation of autoantibodies. In addition, left ventricular remodelling and function was significantly improved by the use of carvedilol combined with the standard treatment regime for six months in the positive group (P < 0.01) when compared to the negative group (P < 0.05). CONCLUSIONS: Carvedilol treatment significantly decreases frequency and geometric mean titer in patients with all three autoantibodies, even up to complete ablation, and significantly improved cardiac function and remodelling. The effect of carvedilol is probably correlated to the presence of all three autoantibodies.

9.
Spectrochim Acta A Mol Biomol Spectrosc ; 223: 117284, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31229902

RESUMO

In this article, a novel fluorescent probe (NRBE) for detecting H2O2 was developed using benzyl boronic ester as the H2O2-recognized group and Nile red as the matrix. The probe has several advantages, such as good selectivity, high sensitivity (LOD = 75 nM), good water solubility and emission in the near-infrared region (ex/em:585/670 nm). With the NRBE probe, the endogenous H2O2 in human hepatocellular carcinoma cells BEL-7402, was detected, and the H2O2 generated during the ischemia-reperfusion of the cells was imaged. These results show that NRBE can be applied for real-time detection of H2O2 in biological systems.


Assuntos
Corantes Fluorescentes/química , Peróxido de Hidrogênio/análise , Oxazinas/química , Espectroscopia de Luz Próxima ao Infravermelho , Sobrevivência Celular , Teoria da Densidade Funcional , Corantes Fluorescentes/síntese química , Células HeLa , Humanos , Oxazinas/síntese química , Espectrometria de Fluorescência , Eletricidade Estática
10.
J Cardiol ; 74(3): 251-257, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30878354

RESUMO

BACKGROUND: Peripartum cardiomyopathy (PPCM) is characterized by heart failure. Our previous study found that autoantibodies against the M2-muscarinic receptor (anti-M2-R) are increased in PPCM patients. We aimed to evaluate the association of anti-M2-R on prognosis of PPCM patients with standard treatment. METHODS: Synthetic peptides corresponding to the M2 receptor served as the target antigens in an enzyme-linked immunosorbent assay experiment. They were used to screen the sera of 80 PPCM patients, who were separated into anti-M2-R-negative and positive groups according to their anti-M2-R reactivity. Clinical assessment and echocardiography examination were performed at baseline and after 5 years with a standard treatment regimen. The endpoint events were compared after 5 years of follow-up. RESULTS: There were 76 PPCM patients who completed the final data analysis, including 36 in the anti-M2-R (+) group and 40 in the anti-M2-R (-) group. Both groups showed improvement in the left ventricular end-diastolic and end-systolic dimensions and the ejection fraction with standard treatment regimens for 5 years (all p<0.001). Patients in the anti-M2-R (-) group had greater tolerance and were more rapidly titrated to metoprolol, and they had better improvement in cardiac function than patients in the anti-M2-R (+) group (p<0.05). Patients in the anti-M2-R (-) group had a marked decrease in re-hospitalization (p<0.05), but not in all-cause mortality or cardiovascular mortality. Being positive for anti-M2-R increased the risk of PPCM (OR=4.7, 95% CI 1.8-12.2, p=0.002). CONCLUSIONS: PPCM patients, especially anti-M2-R (-) patients, have a relatively better prognosis than other patients. We posit that the presence of anti-M2-R may be involved in the pathogenesis of PPCM.


Assuntos
Autoanticorpos/sangue , Cardiomiopatias/imunologia , Insuficiência Cardíaca/imunologia , Complicações Cardiovasculares na Gravidez/imunologia , Receptor Muscarínico M2/imunologia , Adulto , Autoanticorpos/imunologia , Cardiomiopatias/sangue , Ecocardiografia , Ensaio de Imunoadsorção Enzimática , Feminino , Insuficiência Cardíaca/sangue , Humanos , Testes para Triagem do Soro Materno , Período Periparto , Gravidez , Complicações Cardiovasculares na Gravidez/sangue , Prognóstico , Estudos Prospectivos
11.
Life Sci ; 210: 158-165, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30189214

RESUMO

AIMS: The present study describes the derivation and validation of the Chronic Heart Failure Severity Index (CHFSI). MAIN METHODS: The CHFSI was derived using data obtained from a single-center prospective cohort study (2000-2014) that enrolled 756 patients. Logistic regression was used to identify independent predictors of mortality and quality of life over a 15-year follow-up period. KEY FINDINGS: The score was validated at the first 5-year (n = 644), second 5-year (n = 364), and third 5-year (n = 262). Independent predictors of mortality were older age (OR = 2.04, P < 0.001), etiology score (OR = 2.61, P < 0.001), faster heart rate (OR = 1.46, P = 0.027), higher systolic blood pressure (OR = 2.35, P < 0.001), and left ventricular ejection fraction ≤45% (OR = 1.97, P = 0.018). The derived CHFSI predicted the mortality, and the AUC for the logistic model was 0.78 (95% confidence interval = 0.74-0.81, P < 0.001). Based on the logistic model, an integer scoring system was derived. Patients were classified into three groups: low risk (0-7 points), intermediate risk (8-11 points) and high risk (≥12 points) groups. The cumulative mortality for 15 years was 45.5% (125/275), 84.0% (204/243), and 100% (99/99), respectively (P < 0.001). The 6-min walk test revealed a significant difference in quality of life among patients in the low, medium and high risk groups (all, P < 0.0001). SIGNIFICANCE: The CHFSI is a very useful clinical predictive tool that identifies patients at risk of future mortality and their quality of life across healthcare systems.


Assuntos
Insuficiência Cardíaca/mortalidade , Qualidade de Vida , Índice de Gravidade de Doença , Adulto , Idoso , Doença Crônica , Feminino , Seguimentos , Insuficiência Cardíaca/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Medição de Risco , Taxa de Sobrevida
12.
Leuk Lymphoma ; 59(3): 717-724, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28679329

RESUMO

This study aims to investigate the predictive value of pre-chemotherapy ß1R-AABs by evaluating the response of newly diagnosed symptomatic multiple myeloma (MM) patients to their treatment with a bortezomib-containing regimen. Forty-five de novo MM patients and 50 normal controls (NCs) were prospectively enrolled in this study. Serum titers of ß1R-AABs were detected by ELISA. These 45 MM patients were divided into two groups (positive and negative groups) according to their ß1R-AABs. Follow-up examinations were performed on these patients during chemotherapy induction. The final analysis covered all 45 MM patients, including 19 patients who were positive for MM and 26 patients who were negative for MM. Multivariate analysis revealed that pre-chemotherapy ß1R-AABs are possibly independent predictors for less than very good partial response (VGPR) after the bortezomib-containing regimen treatment (odds ratio: 5.967, 95% confidence interval: 1.513-23.531; p = .011). This study demonstrates for the first time that the presence of ß1R-AABs is associated with MM. Pre-chemotherapy ß1R-AABs are independent predictors for less than VGPR in de novo MM patients after the bortezomib-containing regimen was administrated. Bortezomib might not significantly give rise to cardiac impairment in MM patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Autoanticorpos/sangue , Mieloma Múltiplo/sangue , Receptores Adrenérgicos beta 1/imunologia , Autoanticorpos/imunologia , Bortezomib/administração & dosagem , Estudos de Casos e Controles , Dexametasona/administração & dosagem , Doxorrubicina/administração & dosagem , Feminino , Seguimentos , Humanos , Quimioterapia de Indução , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/imunologia , Mieloma Múltiplo/patologia , Terapia Neoadjuvante , Prognóstico , Taxa de Sobrevida
13.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 1): m224, 2007 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-21200570

RESUMO

In the title compound, [Ag(C(10)H(9)N)(H(2)O)](C(6)H(6)NO(3)S), the Ag(I) atom is two-coordinated by one N atom from a 3-methyl-isoquinoline ligand and one water mol-ecule. The 4-amino-benzene-sulfonate counter-anion does not show any bonding inter-actions with the Ag(I) atom. The compound exhibits a three-dimensional supra-molecular structure constructed by hydrogen bonds. Adjacent isoquinoline groups form π-π inter-actions, with a centroid-centroid distance of 3.54 (1) Å. The crystal studied was an inversion twin.

14.
Medicine (Baltimore) ; 96(33): e7727, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28816949

RESUMO

Dilated cardiomyopathy (DCM) is characterized by left ventricular dilation, and is associated with systolic dysfunction and increased action potential duration. Approximately 50% of DCM cases are caused by inherited gene mutations with genetic and phenotypic heterogeneity. Next generation sequencing may be useful in screening unknown mutations in such cases.A family was identified with DCM, in which the affected family members developed heart failure, arrhythmia, and sudden death. Probands and 4 affected family members underwent whole exome sequencing (WES), bioinformatics methods, and gene annotation to identify potentially causative variants. The Sanger sequencing method was used to verify the candidate mutation.WES yielded 2,238,831 variations. KCNJ12 (p.Glu334del) was identified as a candidate mutation, and the heterozygous mutation was verified by Sanger sequencing.Our study emphasizes the application of WES in identifying causative mutations in DCM. This report is the first to describe the KCNJ12 gene as a cause of DCM in patients.


Assuntos
Cardiomiopatia Dilatada/genética , Exoma/genética , Canais de Potássio Corretores do Fluxo de Internalização/genética , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Polimorfismo de Nucleotídeo Único
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 26(9): 1753-6, 2006 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-17112063

RESUMO

Important chemical constituents analysis for the total flavone and total saponin in Gynostemma pentaphyllum is described. The colour reactions of flavones and saponines with vanillin-perchloric acid in acetic acid produced the good absorptions at 451 and 547 nm, but the absorption peaks too overlapped to be determined simultaneously. A new method for the total flavone and the total saponin in Gynostemma pentaphyllum to be determined by signal multiplier spectrophotometry simultaneously without any preliminary separation was proposed. For quantitative analysis, the rutinum as a standard of the total flavone and the ginsenoside Rb1 as standard of the total saponin were applied. The experiment results showed that the regression equations of concentration and deltaA were obtained: deltaAflavone = 0.0133+4.417 0Cflavone, relation coefficient rflavone = 0.9994, and the total flavone concentrations were in 0-0. 16 microg x mI(-1) with deltaA obeying linear relation; deltaAsaporin = 2.775 5Csaponin -0.8881 x 10(-2), relation coefficient rsaponin = 0.9991, and the total saponin concentrations were in 0-0.30 microg x mL(-1) with deltaA obeying linear relation respectively. The recovery ratio was 104.0%-113.0% and 86.8%-94.6% respectively. The RSDflavone was less than 0.58% (n = 9) and RSDsaponin was less than 0. 35% (n=9) respectively. The proposed method is simple, rapid accurate and feasible.


Assuntos
Flavonoides/análise , Gynostemma/química , Saponinas/análise , Espectrofotometria/métodos , Estudos de Viabilidade , Flavonas , Ginsenosídeos/análise , Reprodutibilidade dos Testes
16.
J Chromatogr A ; 1091(1-2): 102-9, 2005 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-16395798

RESUMO

Pre-column derivatization allowed stacking amino acid enantiomers on C18 reversed-phase micro extraction columns, thus facilitating sample loading in capillary HPLC/tandem mass spectrometry. Two tagging reagents, i.e. 7-fluoro-4-nitrobenzoxadiazole (NBD-F) and 1-fluoro-2,4-dinitrobenzene (DNB-F) were evaluated. Both of them reacted readily with amino acids at an elevated temperature, resulting in derivatives that were effectively stacked and suitable for a sensitive MS/MS detection as well. Separation of the tagged enantiomers on a teicoplanin chiral stationary phase (CSP) with mobile phases compatible with MS detection was investigated. NBD-amino acid enantiomers (12 pairs) tested were all base-line resolved. However, the efforts to separate DNB-F tagged amino acid enantiomers on this CSP were not successful. Separation conditions including pH, organic modifiers, and column dimension were studied. All the NBD-amino acids studied could be sensitively detected by MS/MS detection set in the negative ion mode, but only a few including NBD-Asp, BND-Glu, NBD-Ser, and NBD-Thr were detected in the positive ion mode. Thus, the selectivity for enantiomeric determination of excitatory amino acids (e.g. Asp and Glu) was further improved by choosing MS/MS detection in the positive ion mode.


Assuntos
Aminoácidos/química , Aminoácidos/isolamento & purificação , Dinitrofluorbenzeno/análogos & derivados , Oxidiazóis/química , Aminoácidos/análise , Cromatografia Líquida , Dinitrofluorbenzeno/química , Espectrometria de Massas , Estereoisomerismo , Teicoplanina
17.
Wei Sheng Yan Jiu ; 34(6): 752-4, 2005 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-16535855

RESUMO

OBJECTIVE: To determine the catechin and the antioxidation effect in natural tea and their beverages. METHODS: Three wavelength spectrophotometry can eliminate the absorbance error of interfering components, turbid solution and the scattering effect. Background changedwith concentration changed and asymmetric absorption peak problems can be solved, and the antioxidation effect of natural tea and their beverages was studied by the flow-injection chemiluminescence. RESULTS: The recovery is 95.2%-102.0% and the coefficient of variation is 1.05%. Conclusion The results have shown that natural tea and their beverages are abundant in the catechin compounds and strong antioxidative effect.


Assuntos
Antioxidantes/análise , Catequina/análise , Espectrofotometria/métodos , Chá/química , Antioxidantes/isolamento & purificação , Catequina/isolamento & purificação
18.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(2): 266-9, 2005 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-15852873

RESUMO

Numerous studies dealing with the quantitative determination of total flavonoids in sea-buckthorn fruit juice by spectrophotometry are presented. The flavonoids in sea-buckthorn fruit juice and aluminate produce stable complex whose absorption occurred at longer wavelength. To determine the total flavonoids in sea-buckthorn fruit juice by traditional spectrophotometry method, baseline shift and asymmetric absorption peak occurred on the absorption curve. Quantitative determination of flavonoids in sea-buckthorn fruit juice by three wavelength spectrophotometry method can eliminate the absorbance error caused interfering components in turbid solution and the scattering effect. Background changing with the concentration change and asymmetric absorption peak problems can also be solved. The regression equation of concentration vs deltaA was obtained: deltaA = - 0.00703 + 0.00048c with a relation coefficient gamma = 0.9991. The experimental results demostrate the total flavonoids concentrations in 0-800 microg x mL(-1) with deltaA obeying linear relation when the absorbance was measured at wavelength lambda1 = 495 nm, lambda2 = 415 nm and lambda3 = 368 nm. The recovery is 97.0%-101.0% and the coefficient of variation is 0.058% (n = 9). The method is more advantageous than tranditional spectrophotometry method.


Assuntos
Bebidas , Flavonoides/análise , Hippophae/química , Espectrofotometria/métodos , Algoritmos , Cloreto de Alumínio , Compostos de Alumínio/química , Cloretos/química , Flavonoides/química , Frutas/química , Modelos Químicos , Estrutura Molecular , Reprodutibilidade dos Testes
19.
Int J Clin Exp Pathol ; 8(9): 10861-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26617800

RESUMO

BACKGROUND: The principal aim of this study was to investigate the clinical, epidemiological and pathologic features for a series of 79 cases of adipositas cordis sudden death. METHODS: We analyzed clinical and autopsy pathological features of 79 patients (43 females and 36 males) with adipositas cordis who died suddenly between 1975 and 2010. Data were extracted from China National Knowledge Infrastructure and Wan Fang Database. RESULTS: The average age of the 79 cases was 36.6 ± 1.4 years old ranging from 13 to 68, and 82.3% of them were between 20 to 50 years old. Sudden death was the first symptom in 62 (78.5%) of the cases, only 17 (21.5%) had a history of chest distress or dyspnea. More than 4/5 (87.3%) of the cases had no any past medical history. At autopsy, the subjects' heart weight was mild or moderately increased, and a large amount of fatty tissues but not fibrous or fibro fatty was accumulated underneath the epicardium and infiltrated toward the right ventricle walls, and even infiltrated to all layers of the cardiac walls. Regional epidemiological data showed that about 80% of cases were living north and only 20% were living south of the Yangzi River, but not any familial heredity. CONCLUSION: Adipositas cordis sudden death is a very severe disease, it occurs mostly in youth and middle-aged and sudden death is often the first symptom. There is a significant regional difference, but not any genetic correlation. The pathogenesis of adipositas cordis sudden death should to be further explored.


Assuntos
Tecido Adiposo/patologia , Displasia Arritmogênica Ventricular Direita/epidemiologia , Morte Súbita Cardíaca/epidemiologia , Miocárdio/patologia , Adolescente , Adulto , Idoso , Displasia Arritmogênica Ventricular Direita/mortalidade , Displasia Arritmogênica Ventricular Direita/patologia , Autopsia , Causas de Morte , China/epidemiologia , Bases de Dados Factuais , Morte Súbita Cardíaca/patologia , Feminino , Fibrose , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores de Tempo , Adulto Jovem
20.
J Pharm Biomed Anal ; 31(2): 311-9, 2003 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-12609670

RESUMO

Enantiomers of clenbuterol were directly separated by a new high performance chromatographic method on Chirex 3005 column. Several parameters such as mobile phase composition, column temperature and flow rate were studied. Baseline enantioseparation was achieved, using the optimized mobile phase of n-hexane-1,2-dicholoethane-methanol (54:38:8, v/v/v) at 17 degrees C and 1.0 ml/min, with the separation factor (alpha) 1.43 and the resolution factor (R(S)) 1.81. The mechanism of separation was also discussed. Standard linear calibration cures were established for the R- and S-enantiomers, over the range of 26.1-1,045.8 and 5.7-229.6 nmol/ml, with the correlation coefficient of 0.9999 for both. The limits of detection were 0.47 and 1.04 nmol/ml for R- and S-enantiomers, respectively. Recovery and precision of the method were also evaluated, which had been successfully used to monitor and identify quantitatively the profile of the clenbuterol enantiomers in human serum.


Assuntos
Agonistas Adrenérgicos beta/sangue , Amidas/química , Cromatografia Líquida de Alta Pressão/métodos , Clembuterol/sangue , Calibragem , Humanos , Padrões de Referência , Sensibilidade e Especificidade , Espectrofotometria Ultravioleta
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