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1.
Int Orthop ; 40(1): 59-64, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26130278

RESUMEN

PURPOSE: We discuss the clinical effects of anatomical reconstruction of the lateral ankle ligaments to treat chronic lateral ankle instability (CAI) by creating fibular channels with a patient-specific navigational template. METHODS: From August 2010 to February 2014, 15 patients presenting with CAI were treated by creating fibular channels with a patient-specific navigational template for anatomical reconstruction of the lateral ankle ligaments. RESULTS: All patients were followed up for nine to 24 months postoperatively (15 months on average); no recurrent CAI was found. Pre- and postoperative American Orthopaedic Foot and Ankle Society (AOFAS) scores for patients in the calcaneofibular ligament (CFL) plus anterior talofibular ligament (ATFL) repair group were 48.3 ± 5.1 and 88.1 ± 6.7) respectively. The difference (average 39.8) showed high statistical significance (P < 0.001). Pre- and postoperative scores in the ATFL group were 50.4 ± 6.2 and 90.3 ± 7.8, respectively. The difference (average 39.9) showed high statistical significance (P < 0.001). Regarding the Good score, 14 patients were rated as "excellent and one as good (good = 100 %). No severe complications were found in the patients in this group. CONCLUSIONS: We studied and successfully built a digital navigation template for creating fibular channels to anatomically reconstruct the lateral ankle ligament. By using the template, fibular channels could be built, and lateral ligaments could be anatomically reconstructed individually, easily and safely, which largely facilitates the treatment of CAI.


Asunto(s)
Traumatismos del Tobillo/cirugía , Articulación del Tobillo/cirugía , Inestabilidad de la Articulación/cirugía , Ligamentos Laterales del Tobillo/cirugía , Procedimientos de Cirugía Plástica/métodos , Adulto , Tobillo , Femenino , Peroné , Estudios de Seguimiento , Humanos , Masculino
2.
Support Care Cancer ; 21(8): 2091-6, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23440545

RESUMEN

OBJECTIVE: This study identifies factors affecting sleep patterns among thoracic surgery patients in the intensive care unit (ICU) and compares the perceptions of sleep-disturbing factors between nurses and patients. METHODS: One hundred and fifty-two patients and 40 nurses were surveyed using the Pittsburgh Sleep Quality Index (PSQI) and self-designed questionnaires (for patients and nurses). All statistical analyses were carried out by SPSS, and the following statistical methods were used to evaluate the data: chi-squared test and logistic regression. RESULTS: Of 152 patients, 46.1 % reported poor sleep quality during their hospitalization; their PSQI total score was 6.95 ± 3.713. Of these, 69.1 % indicated that their sleep quality was poorer than before; 50.0 % of them changed their sleep patterns. Significant discrepancies exist between nurses and patients in the perceptions of sleep-disturbing factors of patients. CONCLUSION: Thoracic surgical patients' perceptions of their sleep in the ICU indicate poor sleep quality, which is decided by a variety of disturbing factors. Perceptions of these factors varied greatly between surveyed patients and nurses.


Asunto(s)
Unidades de Cuidados Intensivos , Percepción , Trastornos del Sueño-Vigilia/epidemiología , Sueño/fisiología , Procedimientos Quirúrgicos Torácicos , Adulto , Anciano , Recolección de Datos , Femenino , Hospitalización , Humanos , Pacientes Internos , Masculino , Persona de Mediana Edad , Enfermeras y Enfermeros , Trastornos del Sueño-Vigilia/enfermería , Trastornos del Sueño-Vigilia/psicología , Encuestas y Cuestionarios
3.
Artículo en Inglés | MEDLINE | ID: mdl-36232236

RESUMEN

China launched the "critical battle against poverty" nationwide in 2012. As its main battlefield, Yunnan province promulgated the "triple medical security" (TMS) policy in 2017. This study, based on the pooled cross-section database of 2015-2020 of registered poor households in Yunnan province, employed the logit model to examine the effect of TMS on the vulnerability as expected poverty (VEP) of these households. It found that increasing the reimbursement rates for overall medical expenses and inpatient expenses and decreasing the proportion of out-of-pocket medical payment to income reduced the VEP; increases in the number of sick people in the family increased its VEP, and although the increase in the reimbursement rate for overall medical expenses or for inpatient expenses partially offset the VEP caused by the increase in the number of chronically ill people in the family, the VEP caused by the increase in the number of critically ill people would increase in the short term with the increase in the reimbursement rate for overall medical expenses or for inpatient expenses. The findings help improve policies concerning the medical security and health of the rural poor population, providing theoretical reference and practical guidance for future research.


Asunto(s)
Composición Familiar , Población Rural , China/epidemiología , Gastos en Salud , Humanos , Políticas , Pobreza
4.
J Exp Clin Cancer Res ; 41(1): 314, 2022 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-36284313

RESUMEN

BACKGROUND: Beta-1,3-galactosyltransferase-4 (B3GALT4) plays a critical regulatory role in tumor biology. However, the role of B3GALT4 in modulating the tumor microenvironment (TME) of neuroblastoma (NB) remains unknown. METHODS: Public datasets and clinical NB samples were collected to evaluate the expression and clinical significance of GD2 and B3GALT4 in NB patients. CCK-8, colony formation, and transwell assays and experiments in tumor-bearing mouse models were conducted to investigate the function of B3GALT4. Flow cytometry, ELISA, immunohistochemistry, immunofluorescence, western blotting, and chemotaxis assays were conducted to ascertain the immunomodulatory mechanism of B3GALT4. The combined therapeutic effect of the lipid raft inhibitor MßCD and anti-GD2 mAb was validated in a murine model of NB. RESULTS: GD2 was overexpressed in NB tissues and high expression of GD2 was associated with poor prognosis in NB patients. B3GALT4 was downregulated in NB tissues, and low expression of B3GALT4 indicated poor prognosis in NB patients. Silencing B3GALT4 significantly enhanced tumor progression both in vitro and in vivo. Meanwhile, the overexpression of B3GALT4 increased the recruitment of CD8+ T lymphocytes via the chemokines CXCL9 and CXCL10. Additionally, B3GALT4 regulated NB-cell GD2 expression and lipid raft formation. Mechanistically, B3GALT4 regulated the expression of CXCL9 and CXCL10 via the c-Met signaling in the lipid rafts and the downstream AKT/mTOR/IRF-1 pathway. The lipid raft inhibitor, MßCD, attenuated B3GALT4 deficiency-induced tumor progression and immune evasion. Last, MßCD combined with anti-GD2 mAb treatment significantly enhanced the antitumor effect and the infiltration of CD8+ T cells. CONCLUSIONS: Upregulation of B3GALT4 promotes the secretion of CXCL9 and CXCL10 to recruit CD8+ T lymphocytes via the GD2-mediated lipid rafts and the c-Met/AKT/mTOR/IRF-1 pathway. Moreover, lipid raft inhibitors may enhance the efficacy of anti-GD2 immunotherapy for NB.


Asunto(s)
Neuroblastoma , Proteínas Proto-Oncogénicas c-akt , Animales , Ratones , Linfocitos T CD8-positivos , Línea Celular Tumoral , Quimiocinas/uso terapéutico , Galactosiltransferasas/uso terapéutico , Gangliósidos/metabolismo , Microdominios de Membrana , Neuroblastoma/tratamiento farmacológico , Neuroblastoma/genética , Neuroblastoma/metabolismo , Sincalida/uso terapéutico , Serina-Treonina Quinasas TOR , Microambiente Tumoral , Proteínas Proto-Oncogénicas c-met/metabolismo
5.
J Cardiovasc Electrophysiol ; 22(10): 1147-53, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21489033

RESUMEN

INTRODUCTION: We sought to extend the use of low-level vagal stimulation by applying it only to the right vagus nerve (LL-RVS) to suppress atrial fibrillation (AF). METHODS: In 10 pentobarbital anesthetized dogs, LL-RVS (20 Hz, 0.1 ms pulse width) was delivered to the right vagal trunk via wire electrodes at voltages 50% below that which slowed the sinus rate (SR) or atrio-ventricular conduction. Electrode catheters were sutured at multiple atrial and pulmonary vein (PV) sites to record electrograms. LL-RVS continued for 3 hours. At the end of each hour, 40 ms of high-frequency stimulation (HFS; 100 Hz, 0.01 ms pulse width) was delivered 2 ms after atrial pacing (during the refractory period) to determine the AF threshold (AF-TH) at each site. Other electrodes were attached to the superior left ganglionated plexi (SLGP) and right stellate ganglion (RSG) so that HFS (20 Hz, 0.1 ms pulse width) to these sites induced SR slowing and acceleration, respectively. Microelectrodes inserted into the anterior right ganglionated plexi (ARGP) recorded neural activity. RESULTS: (1) Three hours of LL-RVS induced a progressive increase in AF-TH at all sites (all P < 0.05). (2) The SR slowing and acceleration response induced by SLGP and RSG stimulation, respectively, was blunted by LL-RVS. (3) The frequency and amplitude of the neural activity recorded from the ARGP were markedly inhibited by LL-RVS. CONCLUSIONS: LL-RVS suppressed AF inducibility and the chronotropic responses to parasympathetic and sympathetic stimulation. Inhibition of neural activity in the GP may be a mechanism underlying these results.


Asunto(s)
Fibras Adrenérgicas , Fibrilación Atrial/prevención & control , Fibras Colinérgicas , Ganglios Autónomos/fisiopatología , Estimulación del Nervio Vago , Animales , Fibrilación Atrial/etiología , Fibrilación Atrial/fisiopatología , Estimulación Cardíaca Artificial , Modelos Animales de Enfermedad , Perros , Estimulación Eléctrica , Técnicas Electrofisiológicas Cardíacas , Atrios Cardíacos/inervación , Venas Pulmonares/inervación , Factores de Tiempo
6.
Chem Commun (Camb) ; 57(2): 247-250, 2021 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-33306075

RESUMEN

Existing CRISPR/cas-based biosensors usually improve sensitivity by target amplification, which is time-consuming and susceptible to impurities in complex biofluid. Herein, this is the first time a cascade CRISPR/cas (casCRISPR) system has been developed, which can provide a detection limit of 1.33 fM (∼1000 times lower than direct Cas13a-based miRNA detection) and single-base resolution for miR-17 detection without resorting to target amplification. casCRISPR can also be applied to detect miRNA in complicated cell extracts and serum samples. Overall, casCRISPR will provide a heuristic idea for CRISPR/cas based biosensing, and could be a promising tool for miRNA diagnostics.


Asunto(s)
Técnicas Biosensibles/métodos , Sistemas CRISPR-Cas/genética , MicroARNs/análisis , Edición Génica , Límite de Detección , MicroARNs/genética , MicroARNs/metabolismo , Reproducibilidad de los Resultados
7.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 26(6): 653-8, 2009 Dec.
Artículo en Zh | MEDLINE | ID: mdl-19953488

RESUMEN

OBJECTIVE: To investigate the characteristics for activated coagulation factor VII(F VIIa) and the R353Q, -323 0/10 bp, HVR4 polymorphisms in the gene in patients with coronary heart disease (CHD) and myocardial infarction from Ningxia Hui and Han populations. METHODS: Four hundred and twenty angiographically proven CHD patients in the Hui population, and 508 healthy blood donors were tested for their plasma levels of coagulation factor VII using recombinant tissue factor method. The coagulation factor VII gene R353Q, -323 0/10 bp and HVR4 genotypes were identified by polymerase chain reaction. In addition, 600 Han patients with CHD and 604 healthy Han control subjects were also investigated. RESULTS: (1) The plasma F VIIa levels was significantly higher in patients with CHD and myocardial infarction than that in healthy control subjects and angor pectoris (P<0.01) in both Hui and Han populations. (2) There were significant differences in the distribution of genotypes and allelic frequencies of the R353Q between myocardial infarction and angor pectoris disease in the Hui population (P<0.05). So was the -323 0/10 bp locus in both the Hui and Han population. (3) The F VIIa level was significantly higher in individuals with RR genotype than those of Q allele carriers in the Hui population. CONCLUSION: There are polymorphisms of the F VII gene R353Q, -323 0/10 bp and HVR4 in the Hui and Han populations. The Q allele might be a protective factor against myocardial infarction in the Hui, and the plasma F VIIa level may be influenced by the R353Q polymorphism of the F VII gene. The 10 allele may be a protective factor against myocardial infarction in both the Hui and Han populations.


Asunto(s)
Pueblo Asiatico/genética , Factor VII/genética , Infarto del Miocardio/etnología , Infarto del Miocardio/genética , Polimorfismo Genético , Anciano , Pueblo Asiatico/etnología , Estudios de Casos y Controles , Factor VII/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/metabolismo
8.
J Cancer ; 10(4): 957-967, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30854102

RESUMEN

Purpose: Trophinin-associated protein (TROAP) is a cytoplasmic protein that plays a significant role in the processes of embryo transplantation and microtubule regulation. However, the relevant survival analysis and cancer progression analysis have not yet been reported. Methods: Eighteen matched pairs of tumor and adjacent non-tumor samples were evaluated to detect the TROAP mRNA level. Immunohistochemistry (IHC) was used to evaluate the TROAP expression in 108 hepatocellular carcinoma patients who underwent surgical resection. Meanwhile, data from the TCGA database was statistically evaluated. Results: In the present study, we detected a significant increase in the TROAP mRNA level in tumor tissues when compared with adjacent non-tumor tissues. Moreover, the upregulation of TROAP was associated with increased serum AFP and GGT; the greater the tumor number was, the larger the tumor size, differentiation grade, and cancer embolus in clinical analysis. In HCC patients, elevated TROAP expression in the primary tumor was positively related to clinical severity, such as poor overall survival and disease-free survival. In addition, both univariate and multivariate survival analysis validated that TROAP expression was a promising independent risk factor for overall survival and disease-free survival in HCC patients. Furthermore, the results derived from the analysis of data from the TCGA database were consistent with previous results. Altogether, our results show that TROAP is a novel crucial regulator of HCC progression and is a potential therapeutic biomarker for HCC patients. Conclusions: Elevated TROAP expression predicted a poor prognosis, and TROAP may serve as a potential biomarker for application in oncotherapy.

9.
Life Sci ; 214: 41-50, 2018 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-30393020

RESUMEN

AIMS: Macrophage-derived foam-cell formation plays a crucial role in the development of atherosclerosis, and liver X receptor alpha (LXRα) is a key regulator of lipid metabolism in macrophages. Homocysteine (Hcy) is an independent risk factor of atherosclerosis; however, the regulation of lipid metabolism and role of LXRα induced by Hcy in macrophages is still unknown. The present study aimed to investigate the potential role of Hcy in disordered lipid metabolism and atherosclerotic lesions, especially the effects of Hcy on cholesterol efflux in macrophages and the possible mechanisms. MAIN METHODS: In vitro, lipid accumulation and cholesterol efflux were evaluated in THP-1 macrophages with Hcy intervention. Real-time quantitative PCR and western blot analyses were used to assess mRNA and protein levels. In vivo, atherosclerotic lesions and lipid profiles were evaluated by methionine diet-induced hyperhomocysteinemia (HHcy) in ApoE-/- mice. The LXRα agonist T0901317 was used to verify the role of LXRα in HHcy-accelerated atherosclerosis. KEY FINDINGS: Hcy promoted lipid accumulation and inhibited cholesterol efflux in THP-1 macrophages. HHcy mice showed increased lesion area and lipid accumulation in plaque. Both studies in vitro and in vivo showed decreased expression of ATP binding cassette transporter A1 (ABCA1) and G1 (ABCG1). T0901317 treatment increased ABCA1 and ABCG1 levels; reversed macrophage-derived foam-cell formation in THP-1 macrophages and reduced atherosclerotic lesions in ApoE-/- mice. SIGNIFICANCE: Inhibition of LXRα-mediated ABCA1/ABCG1-dependent cholesterol efflux from macrophages is a novel mechanism in Hcy-accelerated atherosclerosis.


Asunto(s)
Transportador 1 de Casete de Unión a ATP/metabolismo , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 1/metabolismo , Aterosclerosis/metabolismo , Homocisteína/metabolismo , Macrófagos/metabolismo , Animales , Aterosclerosis/patología , Línea Celular , Colesterol/metabolismo , Células Espumosas/metabolismo , Células Espumosas/patología , Homocisteína/sangre , Humanos , Hidrocarburos Fluorados/farmacología , Metabolismo de los Lípidos , Receptores X del Hígado/agonistas , Receptores X del Hígado/metabolismo , Macrófagos/patología , Masculino , Ratones Noqueados para ApoE , Placa Aterosclerótica/tratamiento farmacológico , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patología , Sulfonamidas/farmacología
10.
World J Pediatr ; 11(1): 54-60, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25431041

RESUMEN

BACKGROUND: Neuroblastoma is an embryonic neoplasm originating from the neural crest with cellular heterogeneity as one of its oncobiological characteristics. This study was undertaken to determine whether human neuroblastoma contains stem cell-like cells. METHODS: Twenty patients with neuroblastoma who have been treated in our hospital since January 2005 were divided into pre-operative chemotherapy (10 patients) and non-chemotherapy (10) groups. Tumor specimens of the patients were taken and paraffin sections were made. The expressions of stem cell markers CD133, ABCG2, CD117 and nestin were immunohistochemically detected in the specimens. Neuroblastoma cells were stained with Hoechst 33342 and PI. The side population (SP) cells were analyzed by the fluorescence-activated cell sorter. The disparity drug resistance to cisplatin (DDP) of SP and non-SP cells was measured with MTT colorimetric assay. The oncogenicity of SP and non-SP cells was identified in nude mice. RESULTS: There was no significant difference in the expression intensity of CD117 and nestin between the two groups of specimens (P>0.05). There was a significant difference between the two groups in terms of the expression intensity of CD133 and ABCG2 (P<0.05). The SP cells accounted for 0.2%-1.3% of the total human neuroblastoma cells and were decreased to 0.1%-0.5% after verapamil treatment. The SP and non-SP cells showed disparity in cell growth experiment and drug resistance to DDP. Oncogenicity experiment revealed that nude mice could erupt tumor by an injection of l×10(6) SHSY5Y and WIV SP cells. However, the nude mice could not form tumor by an injection of l×10(6) non-SP cells. CONCLUSION: Neuroblastoma might contain cancer stem cell-like cells.


Asunto(s)
Células Madre Neoplásicas/patología , Neuroblastoma/patología , Células de Población Lateral/patología , Antígeno AC133 , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Transportadoras de Casetes de Unión a ATP/metabolismo , Animales , Antígenos CD/metabolismo , Proliferación Celular , Niño , Colorimetría , Glicoproteínas/metabolismo , Humanos , Inmunohistoquímica , Ratones Desnudos , Proteínas de Neoplasias/metabolismo , Células Madre Neoplásicas/metabolismo , Nestina/metabolismo , Neuroblastoma/metabolismo , Péptidos/metabolismo , Proteínas Proto-Oncogénicas c-kit/metabolismo , Células de Población Lateral/metabolismo
11.
Heart Rhythm ; 12(4): 809-17, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25533588

RESUMEN

BACKGROUND: Extremely low-level electromagnetic fields have been proposed to cause significant changes in neural networks. OBJECTIVE: We sought to investigate whether low-level electromagnetic fields can suppress atrial fibrillation (AF). METHODS: In 17 pentobarbital anesthetized dogs, bilateral thoracotomies allowed the placement of multielectrode catheters in both atria and at all pulmonary veins. AF was induced by rapid atrial pacing (RAP) or programmed atrial extrastimulation. At baseline and end of each hour of RAP, during sinus rhythm, atrial programmed stimulation gave both the effective refractory period (ERP) and the width of the window of vulnerability. The latter was a measure of AF inducibility. Microelectrodes inserted into the anterior right ganglionated plexi recorded neural firing. Helmholtz coils were powered by a function generator inducing an electromagnetic field (EMF; 0.034 µG, 0.952 Hz). The study sample was divided into 2 groups: group 1 (n = 7)-application of EMF to both cervical vagal trunks; group 2 (n = 10)-application of EMF across the chest so that the heart was located in the center of the coil. RESULTS: In group 1, EMF induced a progressive increase in AF threshold at all pulmonary vein and atrial sites (all P < .05). In group 2, the atrial ERP progressively shortened and ERP dispersion and window of vulnerability progressively increased (P < .05 compared to baseline values) during 3 hours of RAP and then returned to baseline values during 3 hours of combined application of RAP and EMF (P < .05 compared to the end of the third hour of RAP). The frequency and amplitude of the neural activity recorded from the anterior right ganglionated plexi were markedly suppressed by EMF in both groups. CONCLUSION: Pulsed EMF applied to the vagal trunks or noninvasively across the chest can significantly reverse AF inducibility.


Asunto(s)
Fibrilación Atrial , Campos Electromagnéticos , Estimulación del Nervio Vago/métodos , Animales , Fibrilación Atrial/fisiopatología , Fibrilación Atrial/terapia , Perros , Técnicas Electrofisiológicas Cardíacas/métodos , Atrios Cardíacos/cirugía , Sistema de Conducción Cardíaco/fisiopatología , Modelos Animales , Venas Pulmonares/cirugía
12.
Zhongguo Gu Shang ; 28(3): 252-5, 2015 Mar.
Artículo en Zh | MEDLINE | ID: mdl-25936196

RESUMEN

OBJECTIVE: To investigate the clinical therapeutic results of allograft tendon for anatomical reconstruction of medial patellofemoral ligament (MPFL) for the treatment of patellar dislocations. METHODS: From September 2008 to June 2013, 16 patients with patellar dislocation underwent MPFL reconstructions. There were 2 males and 14 females, aged 11 to 27 years old (16 years old on average). Patellar dislocations occurred in 11 left and 5 right knees. The disease course ranged from 3 to 10 years. The frequency of dislocation ranged from 9 to 33 times (19 times on average). Affected knee joints showed patellar instability; the range of action for patella obviously increased. The X-ray films showed patellar dislocation. The preoperative Q angle was (36 ± 9)°, and the congruence angle was (63 ± 18)°. Reconstruction was performed via allograft tendon. Allograft tendon was fixed through the superomedial pole of the patella, and the other end was fixed at the natural MPFL insertion site near the medial femoral condyle with an interference screw in a bone tunnel. All the patients were evaluated postoperatively; Kujala patellofemoral scores, objective knee function, complications, and reoperations were assessed. RESULTS: Primary healing was achieved in all cases. No infection or necrosis and absorption of grafts was observed. All the patients were followed up for an average of 16.4 months (ranged, 10 to 24 months) postoperatively. At the latest follow-up, all the patients had no pain, swelling and patellar instability; neither patella redislocation nor fracture occurred. The X-ray films showed good position of tunnel 6 months after operation, and the congruence angle was (5 ± 9)°, showing statistically significant difference when compared with preoperation (P < 0.05). The postoperative Q angle was (17 ± 8)°, the Kujala knee function score improved significantly from 45.20 ± 9.20 to 89.30 ± 6.40 at the latest follow-up, showing statistically significant difference (P < 0.05). CONCLUSION: MPFL reconstruction improves clinical symptoms. Anatomical MPFL reconstruction is effective for patellar dislocation, and it offers good recovery of the premorbid patella mechanics. The interference screw provides firm fixation. Allograft can avoid the graft harvest site morbidity, but it increases the cost of the surgery.


Asunto(s)
Ligamentos Articulares/cirugía , Luxación de la Rótula/cirugía , Articulación Patelofemoral/cirugía , Procedimientos de Cirugía Plástica/métodos , Tendones/trasplante , Adolescente , Adulto , Aloinjertos , Niño , Femenino , Humanos , Masculino
13.
Heart Rhythm ; 10(3): 428-35, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23183191

RESUMEN

BACKGROUND: We studied the effects of transcutaneous electrical stimulation at the tragus, the anterior protuberance of the outer ear, for inhibiting atrial fibrillation (AF). OBJECTIVE: To develop a noninvasive transcutaneous approach to deliver low-level vagal nerve stimulation to the tragus in order to treat cardiac arrhythmias such as AF. METHODS: In 16 pentobarbital anesthetized dogs, multielectrode catheters were attached to pulmonary veins and atria. Three tungsten-coated microelectrodes were inserted into the anterior right ganglionated plexi to record neural activity. Tragus stimulation (20 Hz) in the right ear was accomplished by attaching 2 alligator clips onto the tragus. The voltage slowing the sinus rate or atrioventricular conduction was used as the threshold for setting the low-level tragus stimulation (LL-TS) at 80% below the threshold. At baseline, programmed stimulation determined the effective refractory period (ERP) and the window of vulnerability (WOV), a measure of AF inducibility. For hours 1-3, rapid atrial pacing (RAP) was applied alone, followed by concomitant RAP+LL-TS for hours 4-6 (N = 6). The same parameters were measured during sinus rhythm when RAP stopped after each hour. In 4 other animals, bivagal transection was performed before LL-TS. RESULTS: During hours 1-3 of RAP, there was a progressive and significant decrease in ERP, increase in WOV, and increase in neural activity vs baseline (all P < .05). With RAP+LL-TS during hours 4-6, there was a linear return of ERP, WOV, and neural activity toward baseline levels (all P < .05, compared to the third-hour values). In 4 dogs, bivagal transection prevented the reversal of ERP and WOV despite 3 hours of RAP+LL-TS. CONCLUSIONS: LL-TS can reverse RAP-induced atrial remodeling and inhibit AF inducibility, suggesting a potential noninvasive treatment of AF.


Asunto(s)
Fibrilación Atrial/terapia , Estimulación Eléctrica Transcutánea del Nervio/métodos , Estimulación del Nervio Vago/métodos , Nervio Vago/fisiopatología , Animales , Fibrilación Atrial/fisiopatología , Modelos Animales de Enfermedad , Perros , Electrocardiografía , Resultado del Tratamiento
14.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 26(10): 1218-22, 2012 Oct.
Artículo en Zh | MEDLINE | ID: mdl-23167107

RESUMEN

OBJECTIVE: To compare the effect of different defect diameters on healing in the middle 1/3 tibia monolayer cortical bone defect mouse model so as to establish an animal model for bone tissue engineering study, mechanism study on bone defect repair, and gene therapy research. METHODS: Ten 8-week-old C57BL/6J mice, weighing (20 +/- 2) g, were randomly divided into 2 groups, 5 mice in each group. The middle 1/3 tibiae monolayer cortical bone defect model of 0.8 mm (group A) or 1.0 mm (group B) in diameter was established with burr drill. At 7, 21, and 28 days after modeling, the molybdenum target X-ray radiography was used to observe the defect repair; at 28 days, Micro CT and three-dimensional imaging were used to evaluate bone defect repair, and tibia specimens were harvested for HE staining. RESULTS: At 7 days after modeling, tibia fracture occurred in 5 mice in group B, no fracture in group A. X-ray films, Micro CT scan, and HE staining showed bony union in group A at 28 days. The quantitative analysis of trabecular bone by Micro CT showed that trabecular number, connectivity density, and bone volume in group A were significantly greater than those in group B (P < 0.05), mean of segmented region--mean 2 was significantly less than that in group B (P < 0.05), but no significant difference was found in trabecular separation and trabecular thickness between 2 groups (P > 0.05). CONCLUSION: The middle 1/3 tibia monolayer cortical bone defect mouse model of 0.8 mm in diameter is the ideal animal model for study repair mechanism of tibia defect or bone tissue engineering.


Asunto(s)
Regeneración Ósea/fisiología , Modelos Animales de Enfermedad , Tibia/lesiones , Cicatrización de Heridas , Animales , Matriz Ósea/lesiones , Matriz Ósea/cirugía , Imagenología Tridimensional , Masculino , Ratones , Ratones Endogámicos C57BL , Reproducibilidad de los Resultados , Tibia/diagnóstico por imagen , Tibia/cirugía , Fracturas de la Tibia/diagnóstico por imagen , Microtomografía por Rayos X
15.
Heart Rhythm ; 9(5): 804-9, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22214613

RESUMEN

BACKGROUND: The mechanism(s) underlying the maintenance of atrial fibrillation (AF) during the first few hours after AF was initiated remains poorly understood. OBJECTIVE: To investigate the roles of the intrinsic cardiac autonomic nervous system in the maintenance of AF at the early stage. METHODS: In 10 anesthetized dogs, we attached multielectrode catheters on atria and pulmonary veins. Microelectrodes inserted into the anterior right ganglionated plexi recorded neural activity. At baseline, programmed stimulation determined the effective refractory period (ERP) and window of vulnerability (WOV), a measure of AF inducibility. For the next 6 hours, AF was simulated by rapid atrial pacing (RAP) and the same parameters were measured hourly during sinus rhythm. A circular catheter was positioned in the superior vena cava for high-frequency stimulation (20 Hz) of the adjacent vagal preganglionics. During 4-6 hours of RAP, we delivered low-level vagal stimulation in the superior vena cava (LL-SVCS), 50% below that which induced slowing of the sinus rate. RESULTS: During the 6-hour RAP, there was a progressive decrease in the ERP and an increase in ERP dispersion, WOV, and neural activity. With LL-SVCS during 4-6-hour RAP, ERP, WOV, and neural activity returned toward baseline levels (all P <.05, compared with the third-hour RAP values). CONCLUSIONS: RAP not only induces atrial electrical remodeling but also promotes autonomic remodeling. These 2 remodeling processes may form a vicious cycle and each may perpetuate the other. These findings may help to explain how AF maintains itself in its very early stage. LL-SVCS both reversed remodeling processes and can potentially break the vicious cycle of "AF begets AF" in the first few hours of AF.


Asunto(s)
Fibrilación Atrial/fisiopatología , Sistema Nervioso Autónomo/fisiopatología , Atrios Cardíacos/fisiopatología , Sistema de Conducción Cardíaco/fisiopatología , Animales , Estimulación Cardíaca Artificial , Perros , Estimulación Eléctrica , Técnicas Electrofisiológicas Cardíacas , Microelectrodos , Estimulación del Nervio Vago
16.
Bioresour Technol ; 102(7): 4759-65, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21296572

RESUMEN

By means of utilizing sunflower oil and Jatropha oil as raw oil respectively, the biodiesel transesterification production and the multi-stage extracting separation were carried out experimentally. Results indicate that dealcoholized crude glycerol can be utilized as the extracting agent to achieve effective separation of methanol from the methyl ester phase, and the glycerol content in the dealcoholized methyl esters is as low as 0.02 wt.%. For the biodiesel separation process utilizing glycerol extracting dealcoholization, its technical and equipment information were acquired through the rigorous process simulation in contrast to the traditional biodiesel distillation separation process, and results show that its energy consumption decrease about 35% in contrast to that of the distillation separation process. The glycerol extracting dealcoholization has sufficient feasibility and superiority for the biodiesel separation process.


Asunto(s)
Biocombustibles , Fraccionamiento Químico/métodos , Glicerol/química , Jatropha/química , Aceites de Plantas/química , Esterificación , Ésteres/aislamiento & purificación , Metanol/aislamiento & purificación , Aceite de Girasol
17.
Bioresour Technol ; 101(19): 7368-74, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20457516

RESUMEN

For the two-step transesterification biodiesel production made from the sunflower oil, based on the kinetics model of the homogeneous base-catalyzed transesterification and the liquid-liquid phase equilibrium of the transesterification product, the total methanol/oil mole ratio, the total reaction time, and the split ratios of methanol and reaction time between the two reactors in the stage of the two-step reaction are determined quantitatively. In consideration of the transesterification intermediate product, both the traditional distillation separation process and the improved separation process of the two-step reaction product are investigated in detail by means of the rigorous process simulation. In comparison with the traditional distillation process, the improved separation process of the two-step reaction product has distinct advantage in the energy duty and equipment requirement due to replacement of the costly methanol-biodiesel distillation column.


Asunto(s)
Biocombustibles/análisis , Biotecnología/métodos , Hidróxido de Sodio/química , Catálisis , Simulación por Computador , Destilación , Esterificación
18.
J Agric Food Chem ; 56(13): 5247-53, 2008 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-18547049

RESUMEN

Nineteen novel indene-substituted oxime ether strobilurins, which used an indene group to stabilize the ( E)-styryl group in SYP-Z071 (an unsaturated oxime strobilurin fungicide under development by the Shenyang Research Institute of Chemical Industry), were designed and synthesized. The biological assay results showed that all compounds possessed good or excellent fungicidal activities. It was found that most of the compounds showed higher fungicidal activities against Pyricularia oryzae, Phytophthora infestans, Erysiphe graminis, and Colletotrichum lagenarium than SYP-Z071 at the tested concentration. The biological assay results also indicated that most of the compounds exhibited higher in vivo fungicidal activities against cucumber Pseudoperonospora cubensis and C. lagenarium than the commercial fungicides trifloxystrobin and kresoxim-methyl at a concentration of 6.25 mg/L. Furthermore, it was found that alpha-(methoxyimino)- N-methylphenylacetamide oxime ethers 6m- s exhibited a broad spectrum and remarkably higher activities against all tested fungi. Especially, the 6-methylindene-substituted compound 6p was identified as the most promising candidate for further study.


Asunto(s)
Acrilatos/síntesis química , Acrilatos/farmacología , Hongos/efectos de los fármacos , Fungicidas Industriales/síntesis química , Fungicidas Industriales/farmacología , Acrilatos/química , Éteres , Fungicidas Industriales/química , Indenos/síntesis química , Indenos/química , Indenos/farmacología , Estructura Molecular , Oximas/síntesis química , Oximas/química , Oximas/farmacología , Relación Estructura-Actividad
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