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1.
Zhonghua Xin Xue Guan Bing Za Zhi ; 47(4): 305-310, 2019 Apr 24.
Artículo en Zh | MEDLINE | ID: mdl-31060190

RESUMEN

Objective: Previous cross-sectional studies suggested that elevated levels of total cholesterol content of erythrocyte membrane (CEM) could significantly increase the risk of acute coronary syndrome (ACS). The purpose of the present study was to assess the predictive value of baseline CEM levels for the risk of clinical endpoint events in patients with ACS through prospective follow-up studies. Methods: This study is a prospective follow-up study, which consisted of 859 patients with first ACS (698 patients with unstable angina pectoris and 161 patients with acute myocardial infarction), diagnosed and hospitalized in the First and Second Affiliated Hospital of Anhui Medical University. The routine blood lipid levels and CEM were measured. Patients were divided into two groups according to the median of baseline CEM: CEM≤131.56 µg/mg group (n=430) and CEM>131.56 µg/mg group (n=429). Patients were followed up at 6 months interval. The clinical endpoints were nonfatal myocardial infarction, nonfatal stroke, all-cause mortality, all-cause mortality, heart failure requiring hospitalization, and coronary artery revascularization. Kaplan-Meier curve analysis and Cox proportional hazard model were used to analyze the impact of elevated CEM on the occurrence of clinical end-point events. HR values and 95%CI of each variable were obtained. Cox regression analysis of all-cause mortality was performed according to whether patients had risk factors for coronary heart disease (hypertension, diabetes, smoking and elevated LDL-C) and whether they were treated with PCI. Results: The follow-up time was 1 640 (1 380, 2 189) days. Cox analysis after adjustment showed that an elevated baseline of CEM (>131.56 µg/mg) was associated with an increased risk of all-cause mortality (HR=1.690, 95%CI 1.041-2.742, P=0.034), but had no significant predictive effect on the other clinical endpoints. Subgroup analysis showed that elevated baseline CEM levels in ACS patients with LDL-C>1.8 mmol/L (HR=1.687, 95%CI 1.026-2.774, P=0.039), receiving in-hospital PCI (HR=2.365, 95%CI 1.054-5.307, P=0.037), or male (HR=1.794, 95%CI 1.010-3.186, P=0.046) were associated with an increased risk of all-cause mortality. Conclusion: The results showed that elevated CEM levels can increase the risk of all-cause mortality in ACS patients.


Asunto(s)
Síndrome Coronario Agudo , Colesterol , Intervención Coronaria Percutánea , Síndrome Coronario Agudo/sangre , Síndrome Coronario Agudo/diagnóstico , Colesterol/sangre , Estudios Transversales , Membrana Eritrocítica , Femenino , Estudios de Seguimiento , Humanos , Masculino , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Factores de Riesgo
3.
Zhonghua Yi Xue Za Zhi ; 96(43): 3494-3498, 2016 Nov 22.
Artículo en Zh | MEDLINE | ID: mdl-27903345

RESUMEN

Objective: To assess the image quality, radiation dose and diagnostic efficiency of peripheral arterial CT angiography (CTA) performed at tube voltage of 70 and 120 kV. Methods: Between January 2014 and December 2015, a total of 200 consecutive patients with known or suspected lower extremity arteriosclerosis obliterans (LEASO) underwent CTA.Patients were randomly divided into 2 groups by different scanning protocols.Group A (n=100): 70 kV and 0.8 ml/kg contrast agent, group B (n=100): 120 kV and 100 ml contrast agent.The vessel enhancement, image noise, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of 3 segments were quantified for each protocol.30 patients in group A (420 vessels) and 28 patients in group B (384 vessels) confirmed by DSA.Based on vessel assessments, compared with DSA findings, the diagnostic efficacy of 70 kV and 120 kV protocols for the detection of stenoses over 50% was evaluated.The dose of radiation and contrast agent were recorded.Subjective image quality was evaluated. Results: The subjective image quality of segment crural of group A was significantly higher than that of group B (2.20±0.36 vs 1.72±0.34, P<0.01). The enhancement of 3 segments in group A (500 HU) were significantly higher than these in group B (310 HU) (P<0.05). For the detection of stenoses over 50%, the sensitivity, positive and negative predictive values and accuracy of segment crural in group A (98.6%, 95.8%, 98.1%, 96.7%) were significantly higher than that in group B (90.9%, 88.5%, 91.0%, 89.7%) (P<0.05). Mean DLP for 70-kV protocol was significantly lower than that for 120-kV protocol ( (396±34) vs (1 041±159) mGy·cm, P=0.001). Mean dose of contrast agent and the total amount of iodine for 70-kV protocol were significantly lower than that for 120-kV protocol (53.5 vs 100 ml; 18.7 vs 35 g; P<0.01). Conclusion: CT angiography of peripheral arteries with a low tube voltage of 70 kV and low dose of iodine provides reliable information and serves as a rapidly performed and easily available imaging modality in the diagnosis of LEASO.


Asunto(s)
Angiografía por Tomografía Computarizada , Enfermedad Arterial Periférica , Humanos , Relación Señal-Ruido
4.
5.
Dalton Trans ; 45(7): 3102-10, 2016 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-26777518

RESUMEN

Recently, the +2 formal oxidation state in soluble molecular complexes for lanthanides (La-Nd, Sm-Lu) and actinides (Th and U) has been discovered [W. J. Evans, et al., J. Am. Chem. Soc., 2011, 133, 15914; J. Am. Chem. Soc., 2012, 134, 8420; J. Am. Chem. Soc., 2013, 135, 13310; Chem. Sci., 2015, 6, 517]. To explore the nature of the bonding and stabilities of the low-valent actinide complexes, a series of divalent actinide species, [AnCp'3](-) (An[double bond, length as m-dash]Th-Am, Cp' = [η(5)-C5H4(SiMe3)](-)) have been investigated in THF solution using scalar relativistic density functional theory. The electronic structures and electron affinity properties were systematically studied to identify the interactions between the +2 actinide ions and Cp' ligands. The ground state electron configurations for the [AnCp'3](-) species are [ThCp'3](-) 6d(2), [PaCp'3](-) 5f(2)6d(1), [UCp'3](-) 5f(3)6d(1), [NpCp'3](-) 5f(5), [PuCp'3](-) 5f(6), and [AmCp'3](-) 5f(7), respectively, according to the MO analysis. The total bonding energy decreases from the Th- to the Am-complex and the electrostatic interactions mainly dominate the bonding between the actinide atom and ligands. The electron affinity analysis suggests that the reduction reaction of AnCp'3→ [AnCp'3](-) should become increasingly facile across the actinide series from Th to Am, in accord with the known An(iii/ii) reduction potentials. This work expands the knowledge on the low oxidation state chemistry of actinides, and further motivates and guides the synthesis of related low oxidation state compounds of 5f elements.

7.
Br J Radiol ; 88(1052): 20150005, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26055504

RESUMEN

OBJECTIVE: To evaluate the feasibility of high-pitch spiral CT in imaging vascular anomalies (VAs) with affluent blood flow in the head and neck of infants and children. METHODS: For patients with suspected VAs and affluent blood flow pre-detected by ultrasound, CT was performed with high-pitch mode, individualized low-dose scan protocol and three-dimensional (3D) reformation. A five-point scale was used for image quality evaluation. Diagnostic accuracy was calculated with clinical diagnosis with/without pathological results as the reference standard. Radiation exposure and single-phase scan time were recorded. Treatment strategies were formulated based on CT images and results and were monitored through follow-up results. RESULTS: 20 lesions were identified in 15 patients (median age of 11 months). The mean score of image quality was 4.13 ± 0.74. 7 patients (7/15, 46.67%) were diagnosed with haemangiomas, 6 patients (6/15, 40%) were diagnosed with venous malformations and 2 patients (2/15, 13.33%) were diagnosed with arteriovenous malformations. The average effective radiation doses of a single phase and of the total procedure were 0.27 ± 0.08 and 0.86 ± 0.21 mSv. The average scanning time of a single phase was 0.46 ± 0.09 s. After treatment, 13 patients (13/15, 86.67%) achieved excellent results, and 2 patients (2/15, 13.33%) showed good results in follow-up visits. CONCLUSION: High-pitch spiral CT with an individualized low-dose scan protocol and 3D reformation is an effective modality for imaging VAs with affluent blood flow in the head and neck of infants and children when vascular details are needed and ultrasound and MRI could not provide the complete information. ADVANCES IN KNOWLEDGE: This study proposes an alternative modality for imaging VAs with affluent blood flow.


Asunto(s)
Cabeza/irrigación sanguínea , Cuello/irrigación sanguínea , Enfermedades Vasculares/diagnóstico por imagen , Malformaciones Vasculares/diagnóstico por imagen , Niño , Preescolar , Estudios de Factibilidad , Femenino , Estudios de Seguimiento , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Neoplasias de Cabeza y Cuello/terapia , Hemangioma/diagnóstico por imagen , Hemangioma/terapia , Humanos , Lactante , Masculino , Variaciones Dependientes del Observador , Dosis de Radiación , Tomografía Computarizada Espiral , Enfermedades Vasculares/terapia , Malformaciones Vasculares/terapia
8.
Talanta ; 38(12): 1487-91, 1991 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18965328

RESUMEN

The synthesis of p-MPAQ and the electroanalytical chemical properties of the nickel(II)-p-MPAQ complex are reported in this paper. A sensitive adsorptive cathodic stripping procedure for trace nickel determination was developed. For a 3-min preconcentration time the detection limit is 3.0 x 10(-11)M.

9.
Sheng Li Xue Bao ; 42(6): 515-22, 1990 Dec.
Artículo en Zh | MEDLINE | ID: mdl-2127320

RESUMEN

Of the 23 amino acids tested for their effect on the membrane potential of incubated toad oocyte, alanine, leucine and lysine were found to cause a decrease of polarization (depolarization) and K+ permeability, while tryptophan causes an increase of potential (hyperpolarization) and K+ permeability. For the rest 19 amino acids, no membrane effects were observed. Accompanying the alanine, leucine and lysine caused depolarization, the oocyte progesterone content became doubled and the maturation process hastened. These effects could be completely blocked by 1 mmol/L dibutyryl cAMP (db-cAMP) or 50 mumol/L estradiol. Tryptophan on the other hand could block the progesterone (10 mumol/L) induced depolarization but had no effect on the db-cAMP induced hyperpolarization. The regulatory function of the amino acids and steroid hormones underlying oocyte maturation is discussed.


Asunto(s)
Aminoácidos/farmacología , Oocitos/fisiología , Alanina/farmacología , Animales , Bufo bufo , Femenino , Leucina/farmacología , Lisina/farmacología , Potenciales de la Membrana/efectos de los fármacos , Progesterona/metabolismo , Triptófano/farmacología
10.
Sheng Li Xue Bao ; 46(4): 375-80, 1994 Aug.
Artículo en Zh | MEDLINE | ID: mdl-7973829

RESUMEN

Ovaries of immature female rats primed with PMSG-hCG were digested with collagenase-DNAase solution to obtain the corpus luteal cell suspensions. After pre-incubation for 1 h, luteal cell suspensions were then incubated with different factors for 2 h. The progesterone contents in the incubates were measured by RIA. It was demonstrated that high Ca2+/high K+/A23187 significantly enhanced both the basal or hCG-induced progesterone production by rat luteal cells. To the contrast, decreased Ca2+ concentration in medium/EGTA/verapamil had inhibitory effect on progesterone production in the presence of hCG. Tyr had suppressive effect on hCG-induced progesterone production. but not in the presence of high Ca2+/high K+/A23187. The present study suggested that progesterone production by luteal cells of rat is influenced by concentration. Yet, variation in extra/intra-cellular Ca2+ does not affect Tyr suppressive effect on hCG-induced progesterone production. It seems that progesterone production by calcium and hCG occurs through two different mechanisms.


Asunto(s)
Calcio/metabolismo , Gonadotropina Coriónica/farmacología , Células Lúteas/metabolismo , Progesterona/biosíntesis , Animales , Femenino , Ratas , Tirosina/farmacología
11.
Sheng Li Xue Bao ; 41(2): 209-14, 1989 Apr.
Artículo en Zh | MEDLINE | ID: mdl-2762848

RESUMEN

The purpose of the present study was to investigate the effect of tyrosine on progesterone and hCG production by human placental cells in vitro. The results showed that the three concentrations (0.02 mmol/L, 0.2 mmol/L and 2mmol/L) of tyrosine inhibited progesterone secretion by trophoblast cells in vitro. While progesterone secretion was suppressed by tyrosine, hCG secretion was unchanged. Thus, it seems unlikely that the suppression of progesterone production by tyrosine was due to a decrease in hCG production. It was further demonstrated that tyrosine inhibited 3 beta-HSD activity of trophoblast cells, indicating that the progesterone production inhibition by them might be due to the decreased 3 beta-HSD activity of trophoblast cells.


Asunto(s)
Gonadotropina Coriónica/metabolismo , Progesterona/metabolismo , Trofoblastos/metabolismo , Tirosina/farmacología , 3-Hidroxiesteroide Deshidrogenasas/metabolismo , Células Cultivadas , Femenino , Humanos , Embarazo , Trofoblastos/citología
12.
Sheng Li Xue Bao ; 44(3): 269-74, 1992 Jun.
Artículo en Zh | MEDLINE | ID: mdl-1360706

RESUMEN

The effect of exogenous opioid peptides on progesterone production by incubated rat luteal cells was studied. beta-endorphin (beta-EP) stimulated progesterone production in a dose-dependant manner (10(-8)-10(-6) mol/L); dynorphin exhibited a stimulatory effect only at 10(-6) mol/L, while Met-enkephalin had no substantial effect at dose from 10(-10)-10(-6) mol/L. mu-opioid receptor agonists DAGO and morphine also stimulated progesterone production. The stimulatory actions of beta-EP, DAGO and morphine were reversed completely by naloxone. On account of the fact that the beta-EP level in rat plasma is lower than that in the ovary, it seemed that beta-EP may be an intra-ovarian luteotrophic factor and be involved in the regulation of progesterone production. This action of beta-EP may be mediated by mu-opioid subtype receptors.


Asunto(s)
Dinorfinas/farmacología , Células Lúteas/metabolismo , Progesterona/biosíntesis , betaendorfina/farmacología , Animales , Células Cultivadas , Encefalina Ala(2)-MeFe(4)-Gli(5) , Encefalinas/farmacología , Femenino , Células Lúteas/citología , Ratas , Ratas Sprague-Dawley
13.
Yao Xue Xue Bao ; 31(2): 107-11, 1996.
Artículo en Zh | MEDLINE | ID: mdl-8762470

RESUMEN

For further investigation of inhibin which is available only by laborious isolation, four fragments of inhibin alpha subunit (7-28, 37-65, 1-32, Y-1-32) were prepared by solid phase peptide synthesis using the Fmoc strategy. The effects of these fragments on progesterone production of rat corpus luteal (CL) cells in vitro were examined. The results indicate that these four fragments induced significant decrease of basic progesterone production.


Asunto(s)
Inhibinas/síntesis química , Secuencia de Aminoácidos , Animales , Femenino , Inhibinas/química , Inhibinas/farmacología , Células Lúteas/metabolismo , Datos de Secuencia Molecular , Fragmentos de Péptidos , Progesterona/biosíntesis , Ratas
14.
Yao Xue Xue Bao ; 26(1): 25-9, 1991.
Artículo en Zh | MEDLINE | ID: mdl-1887790

RESUMEN

Eleven peptides containing hydroxy-amino-acid have been synthesized manually by stepwise solid-phase method. Three of them were started on BHA-resin, the others on Merrifield-resin. TFMSA/TFA/p-cresol were used as cleaving reagent in all peptide-resin (1-11) cleavage. Furthermore, HF cleaving procedure was also used parallelly to five of those peptide-resins for contrast. No conspicuous difference in yield was found between TFMSA and HF. The purity of all products was checked by the profiles of analytical reversed phase HPLC (C-18) and the data of amino acid analysis. All synthetic peptides were tested for the effect on progesterone production by rat corpus luteum in vitro. Among them, three peptides, GlyTyr-NH2, LysTyr-NH2 and GlySer Lys-OH, showed significant effect (p less than 0.01) on inhibiting hCG-induced progesterone production.


Asunto(s)
Aminoácidos/síntesis química , Anticonceptivos Sintéticos Poscoito/síntesis química , Progesterona/metabolismo , Aminoácidos/farmacología , Animales , Femenino , Células Lúteas/metabolismo , Ratas , Ratas Endogámicas , Relación Estructura-Actividad
15.
Sheng Li Ke Xue Jin Zhan ; 26(3): 204-8, 1995 Jul.
Artículo en Zh | MEDLINE | ID: mdl-8584884

RESUMEN

Inhibin is a glycoprotein hormone composed of an alpha-subunit and a beta-subunit. It suppresses pituitary FSH secretion. Activin is a dimer of beta-subunits of inhibin, which stimulates pituitary FSH secretion. This review is a survey of recent research progress in gene expression and regulation of inhibin/activin, particularly pointing out some questions in studying gene expression of inhibin.


Asunto(s)
Regulación de la Expresión Génica/efectos de los fármacos , Inhibinas/genética , Ovario/metabolismo , Animales , Femenino , Humanos , Inhibinas/biosíntesis , ARN Mensajero/biosíntesis
17.
J Thromb Haemost ; 12(10): 1616-25, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25081279

RESUMEN

BACKGROUND: Venous thrombosis (VT) is a worldwide medical problem. In order to identify individuals at high risk early, it is necessary to find more genetic risk factors. Nowadays, the studies on genetic factors of thrombosis are mainly focused on coagulation and anticoagulation factors. The exploration of other proteins involved in thrombosis and hemostasis may lead to a breakthrough. OBJECTIVES: We used APOH as a candidate gene to investigate the existence of genetic variation that could increase the risk of thrombosis. METHODS/RESULTS: In the current study, with a resequencing method followed by a case-control study, four polymorphisms (c.-32C>A, c.422T>C, c.461G>A, and c.1004G>C) in APOH (encoding ß2 -glycoprotein I) were found to be in high linkage disequilibrium, which could result in three haplotypes. The H2 heterozygotes and H3 homozygotes had approximately 1.5-fold and seven-fold increased risks for VT, respectively. The minor allele frequency in the general population was ~ 10%. In addition, H3 individuals showed a significantly decreased level of ß2 -glycoprotein I, but an increased level of thrombin generation. Functional tests indicated that the mutant ß2 -glycoprotein I had a significantly lower capacity to extend thrombin clotting time and increase thrombin generation potential. CONCLUSIONS: This study revealed APOH as a new candidate gene associated with thrombosis, and further genetic research on this gene in patients in whom the cause of thrombophilia is unknown is therefore warranted.


Asunto(s)
Desequilibrio de Ligamiento , Polimorfismo Genético , Trombosis de la Vena/etnología , Trombosis de la Vena/genética , beta 2 Glicoproteína I/genética , Adulto , Anciano , Alelos , Estudios de Casos y Controles , China , Femenino , Frecuencia de los Genes , Variación Genética , Heterocigoto , Homocigoto , Humanos , Masculino , Persona de Mediana Edad , Mutación , Proteínas Recombinantes/metabolismo , Factores de Riesgo , Análisis de Secuencia de ADN
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