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1.
Stroke ; 51(1): 193-201, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31795899

RESUMEN

Background and Purpose- 1/2ABC has been used widely for assessing the volume of intracerebral hematoma. However, it is only suitable for calculating regular and small volume hematomas. Therefore, we re-explored the formula of hematoma volume to find a method that can calculate hematoma volumes accurately, reliably, and quickly. Methods- Computed tomography imaging data of 257 patients with intracerebral hemorrhage were collected. Hematoma volumes were estimated using 3-dimensional Slicer and 7 formulas (π/6ABC, 1/2ABC, 1/3ABC, 2/3SH, 1/2SH, π/6SH, and 2.5/6ABC). Taking the hematoma volumes measured by 3-dimensional Slicer as the reference standard, the accuracy and reliability of the 7 formulas were evaluated. Furthermore, the time needed to calculate hematoma volumes by the 1/2SH method was noted for further analysis. Results- (1) The accuracy of the 7 formulas based on the error analysis from the highest to the lowest was: π/6SH, 1/2SH, 2.5/6ABC, 1/3ABC, 1/2ABC, and π/6ABC or 2/3SH. According to concordance analysis and receiver operating characteristic curve analysis, the results from the highest to lowest were as follows: 1/2SH, π/6SH, 2.5/6ABC, 1/3ABC, 1/2ABC, 2/3SH, and π/6ABC. After categorizing cases according to size, shape, and location of hematoma, the results were almost the same as the results for overall accuracy evaluation in any subgroup. (2) Intraclass correlation coefficient (ICC) of 1/2SH in intra and inter-researcher were 0.998 and 0.989, respectively. For the formula π/6SH, intraclass correlation coefficient was the same as that of 1/2ABC. Kappa values of 1/2SH for intra- and inter-observer were 0.992 and 0.913, respectively. For π/6SH, kappa values of within- and between-reader were 0.984 and 0.904, respectively. (3) The average time taken to calculate hematoma volumes by 1/2SH was 74 seconds. Conclusions- The 1/2SH and π/6SH are accurate, reliable, and rapid methods for calculating hematoma volumes. The accuracy and reliability of 1/2SH were slightly higher than those of π/6SH.


Asunto(s)
Hemorragia Cerebral/diagnóstico por imagen , Hematoma/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
2.
Apoptosis ; 18(7): 800-10, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23620435

RESUMEN

A prolonged or excessive adrenergic activation leads to myocyte loss and heart dysfunction; however, how it contributes to heart failure remains poorly defined. Here we show that isoproterenol (ISO) induced aberrant endoplasmic reticulum (ER) stress and apoptotic cell death, which was inhibited by activating the AMP-activated protein kinase (AMPK) in vitro and in vivo. Persistent ISO stimulation suppressed the AMPK phosphorylation and function, resulting in enhanced ER stress and the subsequent cell apoptosis in cardiomyocytes in vitro and in vivo. AMPK activation decreased the aberrant ER stress, apoptosis, and brain natriuretic peptide (BNP) release in ISO-treated cardiomyocytes, which was blocked by AMPK inhibitor Compound C. Importantly, increased ER stress and apoptosis were observed in ISO-treated cardiomyocytes isolated from AMPKα2(-/-) mice. Inhibition of ER stress attenuated the apoptosis but failed to reverse AMPK inhibition in ISO-treated cardiomyocytes. Moreover, metformin administration activated AMPK and reduced both ER stress and apoptosis in ISO-induced rat heart failure in vivo. We conclude that ISO, via AMPK inactivation, causes aberrant ER stress, cardiomyocyte injury, BNP release, apoptosis, and hence heart failure in vivo, all of which are inhibited by AMPK activation.


Asunto(s)
Proteínas Quinasas Activadas por AMP/genética , Insuficiencia Cardíaca/inducido químicamente , Isoproterenol/efectos adversos , Metformina/farmacología , Miocitos Cardíacos/efectos de los fármacos , Proteínas Quinasas Activadas por AMP/antagonistas & inhibidores , Proteínas Quinasas Activadas por AMP/deficiencia , Animales , Apoptosis/efectos de los fármacos , Retículo Endoplásmico/efectos de los fármacos , Retículo Endoplásmico/genética , Retículo Endoplásmico/metabolismo , Estrés del Retículo Endoplásmico/efectos de los fármacos , Regulación de la Expresión Génica , Insuficiencia Cardíaca/enzimología , Insuficiencia Cardíaca/patología , Insuficiencia Cardíaca/prevención & control , Masculino , Ratones , Ratones Noqueados , Miocardio/enzimología , Miocardio/patología , Miocitos Cardíacos/enzimología , Miocitos Cardíacos/patología , Péptido Natriurético Encefálico/metabolismo , Fosforilación , Pirazoles/farmacología , Pirimidinas/farmacología , Ratas , Ratas Sprague-Dawley , Transducción de Señal
3.
Basic Res Cardiol ; 107(4): 274, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22744762

RESUMEN

Electrophysiological properties of implanted mesenchymal stem cells (MSCs) in infarcted hearts remain unclear, and their proarrhythmic effect is still controversial. The intent of this study was to investigate electrophysiological properties and proarrhythmic effects of MSCs in infarcted hearts. Rats were randomly divided into a myocardial infarction (MI) group, a MI-DMEM group (received DMEM medium injection) and MI-MSCs group (received MSCs injection). Survival analysis showed that the majority of engrafted MSCs died at day 9 after transplantation. Engrafted MSCs expressed cardiac markers (MYH, cTnI, Cx43), cardiac ion channel genes (Kv1.4, Kv4.2 and Kir2.1) and potassium currents (I (to), I (K1) and I (KDR)), but did not express Nav1.5, Cav1.2, Na(+) current and Ca(2+) current during their survival. When induced by Ca(2+), implanted MSCs exhibited no contraction ability after being isolated from the heart. Following 8-week electrocardiography monitoring, the cumulative occurrence of ventricular arrhythmias (VAs) was not different among the three groups. However, the prolonged QRS duration in infarcted rats without VAs was significantly decreased in the MI-MSCs group compared with the other two groups. The inducibility of VAs in the MI-MSCs group was much lower than that in the MI and MI-DMEM groups (41.20 vs. 86.67 % and 92.86 %; P < 0.0125). The ventricular effective refractory period in MI-MSCs group was prolonged in comparison with that in the MI and MI-DMEM groups (56.0 ± 8.8 vs. 47.7 ± 8.8 ms and 45.7 ± 6.2 ms; P < 0.01). These results demonstrate that MSCs do not acquire the electrophysiological properties of mature cardiomyocytes during the survival period in the infarcted hearts. However, they can alleviate the electrical vulnerability and do not promote ventricular arrhythmias.


Asunto(s)
Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/fisiología , Infarto del Miocardio/terapia , Animales , Arritmias Cardíacas , Diferenciación Celular , Electrocardiografía , Citometría de Flujo , Técnica del Anticuerpo Fluorescente , Captura por Microdisección con Láser , Infarto del Miocardio/fisiopatología , Miocitos Cardíacos/citología , Miocitos Cardíacos/fisiología , Ratas , Ratas Sprague-Dawley , Reacción en Cadena en Tiempo Real de la Polimerasa
4.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 37(2): 171-5, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16608067

RESUMEN

OBJECTIVE: To investigate the expression of MaxiK channel alpha-subunit during human monocyte-derived macrophages differentiating into foam cells. METHODS: Human peripheral blood monocytes were isolated from male healthy volunteers by density gradient centrifugation, which, by culture, differentiated further into macrophages as a homogeneous monocyte population. The foam cell model originated from human macrophage was established by incubating macrophages with oxidized low density lipoprotein (OxLDL). The expression of MaxiK channel alpha-subunit was investigated by RT-PCR techniques, Western blotting and immunocytochemistry. RESULTS: After incubating macrophages with 30 mg/L OxLDL for 60 hours, the cellular contents of total cholesterol (TC), free cholesterol (FC) and cholesterol ester (CE) were markedly increased and the ratio of CE/TC was further raised from (14.437 +/- 6.781) % to (57.946 +/- 3.507) %. Although the expression of MaxiK channel alpha-subunit was downregulated during human monocyte-derived macrophages differentiating into foam cells, there was no significant difference between macrophages and foam cells (P > 0.05). CONCLUSION: That 30 mg/L OxLDL can lead the monocyte-derived macrophage cultured for 60 hours to differentiate into foam cell, but the expression of MaxiK channel alpha-subunit does not change obviously.


Asunto(s)
Diferenciación Celular/fisiología , Células Espumosas/citología , Subunidades alfa de los Canales de Potasio de Gran Conductancia Activados por Calcio/biosíntesis , Macrófagos/metabolismo , Monocitos/metabolismo , Adulto , Células Cultivadas , Colesterol/biosíntesis , Ésteres del Colesterol/biosíntesis , Células Espumosas/metabolismo , Humanos , Subunidades alfa de los Canales de Potasio de Gran Conductancia Activados por Calcio/genética , Lipoproteínas LDL/farmacología , Macrófagos/citología , Masculino , Monocitos/citología
5.
Sheng Li Xue Bao ; 57(5): 566-72, 2005 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-16220194

RESUMEN

The present study aimed to determine the role of tissue injury in migration of mesenchymal stem cells (MSCs) intravenously transplanted into heart and to establish experimental basis for improving stem cell therapy in its targeting and effectiveness. MSCs were isolated from bone marrow of male Sprague-Dawley rats and purified by density centrifuge and adhered to the culture plate in vitro. Female rats were divided randomly into four groups. Myocardial ischemia (MI) transplanted group received MSCs infusion through tail vein 3 h after MI and compared with sham-operated group or normal group with MSCs infusion, or control group received culture medium infusion. MI was created in female rats by ligating the left anterior descending coronary artery. The heart was harvested 1 week and 8 weeks after transplantation. The characteristics of migration of MSCs to heart were detected with expression of sry gene of Y chromosome by using fluorescence in situ hybridization (FISH). Ultrastructural changes of the ischemic myocardium of the recipient rats were observed by transmission electron microscope (TEM). One week or 8 weeks after transplantation, sry positive cells were observed in the cardiac tissue in both of MI transplanted group and sham-operated group, the number of sry positive cells being significantly higher in MI transplanted group (P<0.01). No significant difference was found in the number of sry positive cells between 1 week and 8 weeks after transplantation. No sry positive cells were observed in the hearts of control and normal group. In addition, the ultrastructure of some cells located in the peri-infarct area of MI rats with MSCs transplantation was similar to that of MSCs cultured in vitro. These results indicate that MSCs are capable of migrating towards ischemic myocardium in vivo and the fastigium of migration might appear around 1 week after MI. The tissue injury and its degree play an important role in the migration of MSCs.


Asunto(s)
Movimiento Celular , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/citología , Isquemia Miocárdica/terapia , Animales , Rastreo Celular , Femenino , Masculino , Miocardio/ultraestructura , Ratas , Ratas Sprague-Dawley
6.
Di Yi Jun Yi Da Xue Xue Bao ; 25(9): 1090-4, 2005 Sep.
Artículo en Zh | MEDLINE | ID: mdl-16174571

RESUMEN

OBJECTIVE: To observe the ultrastructural changes of ischemic myocardium of rats after bone marrow mesenchymal stem cells (MSCs) transplantation. METHODS: Rat models of myocardial ischemia were established by ligating the descending anterior branch of the left coronary artery. The isolated and in vitro cultured MSCs labeled with 4' 6-diamidine-2-phenylindole (DAPI) were injected into the rats via the tail vein and the hearts of the rats were taken 1 week and 8 weeks after transplantation, respectively, for observation under fluorescence microscopy. The ultrastructural changes of the ischemic myocardium of the recipient rats were observed by transmission electron microscope. RESULTS: The third passage of cultured MSCs growing in colonies possessed good homogeneity. One week and 8 weeks after transplantation, DAPI-labeled cells were observed in the heart of the recipient rats, but not in the hearts of control rats. One week after transplantation, ultrastructural observation identified a small number of cells in the peripherals of the infarct area of the recipient rats with similar morphology to that of MSCs cultured in vitro. At 8 weeks,a large number of capillaries were seen in the ischemic myocardium on the peripheral of the infarct area. Ultrastructural observation also revealed some immature myocytes surviving in the ischemic region. CONCLUSION: MSCs is capable in vivo of homing to the ischemic myocardium via the blood circulation, and promote regeneration of the myocardium and blood vessels.


Asunto(s)
Trasplante de Células Madre Mesenquimatosas , Isquemia Miocárdica/patología , Isquemia Miocárdica/cirugía , Miocardio/ultraestructura , Animales , Animales Recién Nacidos , Células de la Médula Ósea/citología , Femenino , Masculino , Ratas , Ratas Sprague-Dawley
7.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 30(3): 270-5, 2005 Jun.
Artículo en Zh | MEDLINE | ID: mdl-16045011

RESUMEN

OBJECTIVE: To investigate the role of adult cardiomyocytes in the differentiation of mesenchymal stem cells (MSCs) into cardiomyocytes. METHODS: Rat MSCs were isolated by a Percoll's gradient solution and cultured in low-glucose Dulbecco' s modified Eagle' s medium (DMEM). After 2 passages, cell-surface antigen CD34, CD71 and CD90 for rat MSCs were determined by flow cytometry, and these MSCs were transfected with pEGFP-N3 by Lipofectamine2000. Then those MSCs labeled with GFP, were cultured in contacted, nocontacted and conditioned with adult rat myocardiocytes. Immunofluorescence staining against alpha-actin, desmin, and troponin-T were performed after 1 week. RESULTS: Immunofluorescence staining was positive against alpha-actin, desmin, and troponin-T on MSCs in contacted culture group. In contrast, no alpha-actin, desmin, and troponin-T expression on MSCs were observed in the noncontacted culture group and the conditioned culture group. CONCLUSION: Direct cell-to-cell contact between MSCs and adult cardiomyocytes may induce differentiation of MSCs into cardiomyocytes.


Asunto(s)
Células de la Médula Ósea/citología , Comunicación Celular , Diferenciación Celular/fisiología , Células Madre Mesenquimatosas/citología , Miocitos Cardíacos/citología , Animales , Antígenos CD34/análisis , Separación Celular , Células Cultivadas , Técnicas de Cocultivo , Femenino , Masculino , Ratas , Ratas Sprague-Dawley , Antígenos Thy-1/análisis
8.
J Med Chem ; 47(14): 3487-90, 2004 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-15214775

RESUMEN

The effect of introducing hydrophobic groups onto the disaccharide portion of the mannopeptimycins has been examined. Under acid-catalyzed conditions dimethyl acetals and ketals react on the terminal mannose of the disaccharide moiety of mannopeptimycin-alpha and the cyclohexylalanyl analogue 2. The preferentially formed monofunctionalized 4,6-acetals and -ketals display potent antibacterial activities against Gram-positive microorganisms, including MRSA, PRSP, and VRE pathogens.


Asunto(s)
Acetales/síntesis química , Antibacterianos/síntesis química , Glicopéptidos , Bacterias Grampositivas/efectos de los fármacos , Acetales/química , Acetales/farmacología , Antibacterianos/química , Antibacterianos/farmacología , Interacciones Hidrofóbicas e Hidrofílicas , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Espectrometría de Masa por Ionización de Electrospray , Relación Estructura-Actividad
9.
J Org Chem ; 63(1): 137-143, 1998 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-11674054

RESUMEN

The feasibility of alpha-ketol equilibration in a fully oxygenated B-ring setting for the rapid, enantioselective construction of an A/B bicyclic model related to Taxol has been examined. The key elements associated with this successful venture include selection of a proper array of protecting groups for the four hydroxyl groups present, suitable catalysis of the 1,2-pinacol-like shift, and an intrinsic dependence on the thermodynamic stabilities of the two alpha-ketol isomers. The key conversion of 13 to 14 is seen to be unidirectional and consequently to offer useful potential serviceability as more advanced thrusts toward Taxol are mounted.

10.
Am J Med Sci ; 346(3): 204-10, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23114200

RESUMEN

BACKGROUND: The objective of the present study was to determine the effect of various concentrations of oleic acid (OA) on KATP channel expression and the potential relationship to exogenous nitrogen monoxide and protein kinase C levels. METHODS: Human umbilical artery smooth muscle cells (HUASMCs), between the 7th and 10th passages, were divided into control group, OA group (final OA concentration of 0, 50, 100 or 200 µmol/L), nitric oxide (NO) intervention group, protein kinase C inhibitor group or GF-109203X (GFX) intervention group. Western immunoblotting was used to detect the protein expression of the KATP channel subunit Kir6.1. Also, quantitative real-time polymerase chain reaction analysis to determine Kir6.1 messenger RNA levels and whole-cell patch clamping to measure KATP currents were performed. RESULTS: The results suggested that OA inhibited Kir6.1 protein and messenger RNA expression in HUASMCs. Under a high concentration of potassium (140 mmol/L), 100 µmol/L OA significantly reduced ATP-sensitive potassium current density, whereas a low extracellular concentration of potassium (5.4 mmol/L) did not influence KATP density. Pretreatment with either exogenous NO or GFX weakened the OA-induced inhibition of KATP in HUASMCs. CONCLUSIONS: The study demonstrated that OA inhibited Kir6.1, a KATP channel subunit, in HUASMCs, and indirectly inhibited the KATP current. In addition, the results indicated that NO and/or GFX partially reversed OA inhibition in HUASMCs.


Asunto(s)
Canales KATP/fisiología , Miocitos del Músculo Liso/efectos de los fármacos , Ácido Oléico/farmacología , Células Cultivadas , Humanos , Indoles/farmacología , Maleimidas/farmacología , Miocitos del Músculo Liso/fisiología , Óxido Nítrico/farmacología , Proteína Quinasa C/antagonistas & inhibidores , ARN Mensajero/metabolismo , Albúmina Sérica Bovina/farmacología , Arterias Umbilicales/citología
11.
J Geriatr Cardiol ; 9(2): 172-9, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22916065

RESUMEN

OBJECTIVE: We performed experiments using Neuregulin-1ß (NRG-1ß) treatment to determine a mechanism for the protective role derived from its beneficial effects by remodeling gap junctions (GJs) during heart failure (HF). METHODS: Rat models of HF were established by aortocaval fistula. Forty-eight rats were divided randomly into the HF (HF, n = 16), NRG-1ß treatment (NRG, n = 16), and sham operation (S, n = 16) group. The rats in the NRG group were administered NRG-1ß (10 µg/kg per day) for 7 days via the tail vein, whereas the other groups were injected with the same doses of saline. Twelve weeks after operation, Connexin 43 (Cx43) expression in single myocytes obtained from the left ventricle was determined by immunocytochemistry. Total protein was extracted from frozen left ventricular tissues for immunoblotting assay, and the ultrastructure of myocytes was observed by transmission electron microscopy. RESULTS: Compared with the HF group, the cardiac function of rats in the NRG group was markedly improved, irregular distribution and deceased Cx43 expression were relieved. The ultrastructure of myocytes was seriously damaged in HF rats, and NRG-1ß reduced these pathological damages. CONCLUSIONS: Short-term NRG-1ß treatment can rescue pump failure in experimental models of volume overload-induced HF, which is related to the recovery of GJs structure and the improvement of Cx43 expression.

12.
Int J Cardiol ; 151(3): 290-5, 2011 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-20579749

RESUMEN

BACKGROUND: Endogenous oestrogen deficiency after menopause is associated with high risk of acute cardiac events and the protection of exogenous oestrogen supplements remains uncertain. This study investigates whether oestrogen therapy protects the heart from ischemic injury in oophorectomised rats. METHODS: Sexually mature female Sprague-Dawley rats (6 for each group) with bilateral oophorectomy underwent selective ligation (occlusion) of left coronary artery for 4 weeks. 17ß-oestradiol (E2) supplements (10 µg, i.m., every other day) were started before (preventive-therapeutic supplement) or after coronary occlusion (therapeutic supplement). RESULTS: In oophorectomised rats plasma levels of E2 declined from 1301 ± 80 to 196 ± 48 pmol/L (p<0.01) and cardiac expression of oestrogen receptors (ER) decreased by ∼60%. E2 supplements recovered the ER expression. Selective ligation of left coronary led myocardial infarction in the left ventricle, with an increase in plasma cardiac troponin I (cTn-I), decrease in systolic blood pressure (SBP), and reduction of left ventricular pressures. Preventive-therapeutic but not therapeutic E2 supplement reduced cTn-I levels (from 21.9 ± 2.0 to 6.0 ± 0.3 ng/mL, p<0.01), minimised infarction (from 37.0 ± 1.2% to 18.1 ± 2.3%, p<0.05), increased SBP (from 82 ± 4.2 to 97 ± 4.4mm Hg, p<0.05), and improved left ventricular end pressures in the oophorectomised rats following coronary occlusion. CONCLUSION: Postmenopausal (ooporectomised) oestrogen supplement commenced before establishment of myocardial ischemia minimises myocardial infarction and ventricular dysfunction following the coronary artery occlusion. Cellular and molecular mechanisms underlying the cardiac protection of oestrogen therapy remain unclear, in which activation of cardiac ER expression and increasing in circulating CD90(+) stem cells may be involved.


Asunto(s)
Cardiotónicos/administración & dosificación , Oclusión Coronaria/prevención & control , Estradiol/administración & dosificación , Infarto del Miocardio/prevención & control , Ovariectomía , Disfunción Ventricular Izquierda/prevención & control , Animales , Oclusión Coronaria/sangre , Oclusión Coronaria/patología , Suplementos Dietéticos , Femenino , Infarto del Miocardio/sangre , Infarto del Miocardio/patología , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Disfunción Ventricular Izquierda/sangre , Disfunción Ventricular Izquierda/patología
13.
Bioorg Med Chem Lett ; 14(1): 279-82, 2004 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-14684343

RESUMEN

A series of ester and carbonate derivatives of the glycopeptide mannopeptimycin alpha (1) with potent activity against G+ bacteria, including the methicillin-resistant staphylococci and vancomycin-resistant enterococci, was synthesized. The SAR data obtained from natural and semisynthetic compounds demonstrated the importance of a hydrophobic group in the terminal mannosyl moiety for antibacterial activity.


Asunto(s)
Antibacterianos/química , Carbonatos/química , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Glicopéptidos , Animales , Antibacterianos/farmacología , Carbonatos/farmacología , Farmacorresistencia Bacteriana Múltiple/fisiología , Ésteres , Ratones , Pruebas de Sensibilidad Microbiana/estadística & datos numéricos , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrollo
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