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A convenient and efficient method for the generation of the iminoxy radical through anodic oxidation was developed for the synthesis of 3,5-disubstituted 1,2,4-oxadiazoles from N-benzyl amidoximes. The transformation proceeds through 1.5-Hydrogen Atom Transfer (1,5-HAT) and intramolecular cyclization. The process features simple operation, mild conditions, broad substrate scope and high functional group compatibility, and provides a facile and practical way for the preparation of 1,2,4-oxadiazoles.
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Optogenetics is an innovative method for precise control of biological function, which makes light manipulation displays more advantages than electric energy because of contactless spatial flexibility and cell-to-cell synchronous communication. The aim of this study was to perform different illumination modes with blue laser to investigate optical control of the mice hearts. In this study, we transfected the light sensitive protein ChR2(H134R) into mouse hearts, which were illuminated with a 473â¯nm laser on the Langendorff apparatus. We recorded all the signals of electrograms (EGs), epicardium monophasic action potential (MAPs) and light output signals to analyze myocardial electrical activity. EGs and MAP showed that ChR2 expression in the heart can be flexibly controlled by blue light across different illumination sites with corresponding triggered ectopic rhythm. Illumination intensity, pulse duration, and impulse frequency were associated with the light capture rate. Continuous illumination with the threshold intensity on the left ventricle had little influence on sinus rhythm and ventricular electrophysiology. Our results support that flexible control of the cardiac rhythm with optogenetics provides an innovative approach to cardiac research and therapy.
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Frecuencia Cardíaca/fisiología , Corazón/fisiología , Corazón/efectos de la radiación , Luz , Animales , Channelrhodopsins/metabolismo , Fenómenos Electrofisiológicos/efectos de la radiación , Fluorescencia , Frecuencia Cardíaca/efectos de la radiación , Ventrículos Cardíacos/efectos de la radiación , Ratones Endogámicos C57BLRESUMEN
Optogenetics is a cell-type specific and high spatial-temporal resolution method that combines genetic encoding of light-sensitive proteins and optical manipulation techniques. Optogenetics technology provides a novel approach for research on cardiac arrhythmia treatment, including pacing, recovering the conduction system, and achieving cardiac resynchronization with precise and low-energy optical control. Photosensitive proteins, which usually act as ion channels, pumps, or receptors, are delivered to target cells, where they respond to light pulses of specific wavelengths, evoke transient flows of transmembrane ion currents, and induce signal transmission. With the development of gene technology, the in vivo efficiency of optogenetics in cardiology has been trialed, and in vitro experiments have been performed to test its potential in cardiac electrophysiology. Challenges for applying optogenetics in large animals and humans include the effectiveness, safety, and long-term expression of photosensitive proteins, unscattered and unattenuated exogenous light stimulation, and the need for implantable miniature light stimulators. Photosensitive proteins, genetic engineering technology, and light equipment are essential for experiments in cardiac optogenetics. Optogenetics may provide an alternative method for evaluating the mechanism of cardiac arrhythmias, testing hypotheses, and treating cardiovascular diseases.
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Arritmias Cardíacas , Optogenética/métodos , Animales , Arritmias Cardíacas/genética , Arritmias Cardíacas/terapia , Electrofisiología Cardíaca/métodos , Electrofisiología Cardíaca/tendencias , HumanosRESUMEN
Similar to traditional wireless sensor networks (WSN), the nodes only have limited memory and energy in low-duty-cycle sensor networks (LDC-WSN). However, different from WSN, the nodes in LDC-WSN often sleep most of their time to preserve their energies. The sleeping feature causes serious data transmission delay. However, each source node that has sensed data needs to quickly disseminate its data to other nodes in the network for redundant storage. Otherwise, data would be lost due to its source node possibly being destroyed by outer forces in a harsh environment. The quick dissemination requirement produces a contradiction with the sleeping delay in the network. How to quickly disseminate all the source data to all the nodes with limited memory in the network for effective preservation is a challenging issue. In this paper, a low-latency and energy-efficient data preservation mechanism in LDC-WSN is proposed. The mechanism is totally distributed. The data can be disseminated to the network with low latency by using a revised probabilistic broadcasting mechanism, and then stored by the nodes with LT (Luby Transform) codes, which are a famous rateless erasure code. After the process of data dissemination and storage completes, some nodes may die due to being destroyed by outer forces. If a mobile sink enters the network at any time and from any place to collect the data, it can recover all of the source data by visiting a small portion of survived nodes in the network. Theoretical analyses and simulation results show that our mechanism outperforms existing mechanisms in the performances of data dissemination delay and energy efficiency.
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OBJECTIVE: To explore the role of leukoaraiosis (LA) on the cognitive function in patients with Parkinson disease (PD). METHODS: The cohort for this study included 63 patients with PD, whom were divided into 3 groups according to cognitive status:with intact cognition (PD-IC, n = 23), with mild cognitive impairment (PD-MCI, n = 23) and with dementia (PDD, n = 17). All the patients were recruited from the Department of Neurology, First Affiliated Hospital, Anhui Medical University between September 2011 and July 2012. The cognitive functions were evaluated by mini-metal state examination (MMSE), the Cambridge cognitive examination-Chinese version (CAMCOG-C), clinical dementia rating (CDR), clock drawing task (CDT) and verbal fluency test, etc. Depression symptoms were assessed by the geriatric depression scale (GDS) while motor symptoms by the Unified Parkinson's Disease Rating Scale-motor (UPDRS-motor) and the Hoehn and Yahr scale (HY). All the patients underwent magnetic resonance imaging (MRI) with a 3.0-T system. LA was rated using the semiquantitative visual rating system proposed by scheltens et al. RESULTS: Both the PD-IC (2.43 ± 2.79) and PD-MCI (4.48 ± 4.33) groups showed significantly lower deep hyperintensities (DHs) scores than the PDD group (7.88 ± 6.69, P = 0.004 and 0.040, respectively), especially in frontal (1.09 ± 1.31; 1.83 ± 1.90; 3.24 ± 2.64, P < 0.05) and parietal areas (0.09 ± 0.29; 0.65 ± 1.03; 1.53 ± 2.32, P < 0.05). There were no significant differences in periventricular (1.57 ± 1.75; 2.52 ± 2.37; 3.24 ± 2.64, P > 0.05), basal ganglia (0.09 ± 0.42; 0.30 ± 0.77; 0.53 ± 1.33, P > 0.05) and infratentorial white matter hyperintensities scores (--; 0.13 ± 0.63; 0.18 ± 0.73, P > 0.05) among three groups. The DHs showed a significant correlation with age (P = 0.003), MMSE (P = 0.009), verbal fluency test (P = 0.009), orientation (P = 0.047) and executive function (P = 0.027) in CAMCOG-C. The multiple regression analysis showed that the MMSE scores were associated significantly with education (P < 0.001, ß = 0.600), DHs (P = 0.001, ß = -0.678) and HY (P = 0.035, ß = -0.480). DHs were the most significantly associated with MMSE scores. CONCLUSION: There was a significant correlation between DHs and multiple domain cognitive impairment in PD, especially in executive function. DHs, which were the most significantly variable associated with MMSE scores, may contribute to cognitive impairment in PD.
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Trastornos del Conocimiento/etiología , Leucoaraiosis , Enfermedad de Parkinson/fisiopatología , Adulto , Anciano , Anciano de 80 o más Años , Demencia/psicología , Femenino , Humanos , Leucoaraiosis/patología , Leucoaraiosis/fisiopatología , Leucoaraiosis/psicología , Masculino , Persona de Mediana Edad , Pruebas NeuropsicológicasRESUMEN
Background: Thyroxine binding globulin (TBG) deficiency is a rare thyroid disease, mostly caused by genetic mutations and acquired by X-linked recessive inheritance. The clinical features of children with TBG deficiency and their family members were summarised and the Serpina7 gene mutation was analysed, providing a reference for the differentiation of TBG deficiency. Methods: Thyroid function was detected in TBG deficient patients, and genetic analysis was performed using polymerase chain reaction (PCR) and direct DNA sequencing to detect the characteristics of TBG mutants. Using "thyroxine binding globulin, gene and mutation" as keywords, PubMed (biomedical literature database), Web of Science and other databases were searched for relevant studies to collect and summarise relevant information. Results: The TBG (14.7 µg/mL), 70% triiodothyronine (T3) (<0.3 nmol/L), total T3 (Tr3) (<0.05 ng/mL) and thyroxine (T4) (14.72 nmol/L) values were lower than normal, while the thyrotropin (TSH) (2.33 uIU/mL), free T3 (FT3) (1.62 pmol/L), and free T4 (FT4) (11.39 pmol/L) values were normal. These values indicate a TBG partially deficient phenotype. Using PCR amplification and direct sequencing of the target gene, a missense mutation in exon 4 of the Serpina7 gene was found in the patient and the father, and the nucleic acid variant was C.909 (exon 4) g > T; the patient was heterozygous and the father was hemizygous. The literature search retrieved a total of 45 studies, most of which were related to mutations in the Serpina7 gene. The mutation locations included exons, introns, enhancers and promoters, with exons the predominant location. A total of 49 variants of the Serpina7 gene were identified. Conclusion: Serpina7 C.909G (P.L303F) is a mutation acquired from the father by X-linked recessive inheritance. The main clinical features of TBG deficiency patients are low serum T4, T3 and TBG levels, normal TSH, FT3 and FT4 levels, and no clinical manifestations.
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OBJECTIVE: To investigate the effect of Chinese compound Shensong Yangxin Capsule ( , SSYX) on myocardial microcirculation in myocardial-infarcted rabbits. METHODS: Myocardial infarction (MI) was established in rabbits by ligation of the left circumflex coronary. Thirty rabbits were randomly divided into the control group, the MI group (model), and the MI treated with SSYX group (MI+SSYX) by a random number table method. After 4 weeks of administration, low-energy real-time myocardial contrast echocardiography (RT-MCE) was conducted to assess the microcirculatory perfusion. Immunofluorescence double staining was used to detect the capillary density. The endothelial ultrastructure was observed with a transmission electron microscope. The mRNA expression levels of vascular endothelial growth factor (VEGF), endothelin 1 (ET-1), prostaglandin I2 (PGI2) and endothelial nitric oxide synthase (eNOS) were measured by real-time quantitative polymerase chain reaction (Real-time PCR). The plasmic levels of ET-1, thromboxane A2 (TXA2), nitric oxide (NO) and von willebrand factor (vWF) were examined with enzyme-linked immunosorbent assays (ELISA). RESULTS: SSYX significantly improved the myocardial blood volume, myocardial micro bubble velocity, and myocardial inflow according to the examination of RT-MCE, and it visibly ameliorated the capillary endothelial structure. Furthermore, compared with the MI group, the plasma levels of TXA2, ET-1 and vWF contents significantly decreased in the MI+SSYX group, and the ET-1 mRNA expression levels of myocardium in the border zone significantly decreased, and the VEGF, PGI2 and eNOS mRNA expression levels significantly increased (all P<0.05). CONCLUSIONS: SSYX has favorable advantages in ameliorating the impaired myocardial microcirculation following MI. The mechanisms of the effect are related to the ability of SSYX in balancing the endothelial-derived vasodilators and vasoconstrictors, and up-regulating the expression of VEGF and eNOS.
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Infarto del Miocardio , Animales , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico , Medicina Tradicional China , Microcirculación , Infarto del Miocardio/tratamiento farmacológico , Miocardio , Conejos , Factor A de Crecimiento Endotelial VascularRESUMEN
This study determines whether near-infrared (NIR) light can drive tissue-penetrating cardiac optical control with upconversion luminescent materials. Adeno-associated virus (AAV) encoding channelrhodopsin-2 (ChR2) was injected intravenously to rats to achieve ChR2 expression in the heart. The upconversion nanoparticles (UCNP) NaYF4:Yb/Tm or upconversion microparticles (UCMP) NaYF4 to upconvert blue light were selected to fabricate freestanding polydimethylsiloxane films. These were attached on the ventricle and covered with muscle tissue. Additionally, a 980-nm NIR laser was programmed and illuminated on the film or the tissue. The NIR laser successfully captured ectopic paced rhythm in the heart, which displays similar manipulation characteristics to those triggered by blue light. Our results highlight the feasibility of tissue-penetration cardiac optogenetics by NIR and demonstrate the potential to use external optical manipulation for non-invasive or weakly invasive applications in cardiovascular diseases.
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The aim of this study is to observe the synergistically enhanced percutaneous penetration and skin analgesia of tetracaine gel containing menthol and ethanol through experimental and clinical studies. Four anesthetic gels containing 4% tetracaine in carbomer vehicle named T-gel (containing no menthol or ethanol), 5%M/T-gel (containing 5% menthol), 70%E/T-gel (containing 70% ethanol, an optimal concentration for antiseptic), and 5%M+70%E/T-gel (containing both 5% menthol and 70% ethanol), respectively, were fabricated. The in vitro mouse skin permeation was investigated using a Franz diffusion cell. The mouse skin morphology was examined by a scanning electron microscope. The in vivo skin analgesic effect in mice was evaluated using the von Frey tests. To determine the efficacy of tetracaine gels for managing the pain in human volunteers, a paralleled, double-blinded, placebo-controlled, randomized controlled trial design combined with verbal pain scores (VPS) was performed. The combination of menthol and ethanol (5%M+70%E/T-gel) conferred significantly higher tetracaine diffusion across full-thickness mouse skin than 5%M/T-gel, 70%E/T-gel, and T-gel. The ultra structure changes of mouse skin stratum corneum treated with 5%M+70%E/T-gel were more marked compared with those of any other tetracaine gel. von Frey tests in mice showed a synergistically enhanced effect of menthol and ethanol on the analgesia of tetracaine gel. The mean VPS were significantly lower for volunteers treated with 5%M+70%E/T-gel than those receiving other gels or the EMLA cream. 5%M+70%E/T-gel possessed the shortest anesthesia onset time, the longest anesthesia duration and the strongest anesthesia efficacy. Seventy percent ethanol in 5%M+70%E/T-gel not only improved the analgesic efficacy of the tetracaine gel through synergistically enhanced percutaneous permeation with menthol but also served as an antiseptic agent keeping drug application site from infection. 5%M+70%E/T-gel is a potential topical anesthesia preparation for clinical use.
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Analgesia , Anestésicos Locales/administración & dosificación , Etanol/administración & dosificación , Metanol/administración & dosificación , Absorción Cutánea , Tetracaína/administración & dosificación , Tetracaína/farmacocinética , Adulto , Animales , Método Doble Ciego , Sinergismo Farmacológico , Femenino , Geles , Humanos , Masculino , RatonesRESUMEN
An novel exfoliation strategy to few-layered graphene (FLG) combined with in situ synthesized amorphous MnOx has been established via a facile and robust ball milling route in the presence of KMnO4. The facile synthesis approach has the features of low cost, environmentally friendly nature and scalable capability. As an anode for lithium-ion batteries, amorphous MnOx@FLG delivered a wonderful electrochemical performance under extremely operational conditions, that is, an excellent reversible capacity of 856 mAh g-1 at a high current density of 1 A g-1 after 75 cycles under a high temperature of 85 °C. Those excellent electrochemical performances could be ascribed to elaborately designed three-dimensional nanostructure, the well-chosen electrolyte, significant incorporation of in situ Mn(IV) nanocrystal and few-layered graphene, and the contribution of pseudocapacitance. Remarkable electrochemical performance under a widely operational temperature window makes the amorphous MnOx@FLG composites promising anode of Li-ion batteries for heavy-duty application.