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1.
Waste Manag Res ; : 734242X231221082, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38193464

RESUMEN

Residents' food waste is a key part of environmental sustainability and food security. This study investigates influencing factors in reducing food waste by constructing a conceptual model examining the relationship between network embeddedness (NE) and food waste behaviour (FWB), using questionnaire data from 853 urban residents in eastern China, as well as the moderating role of incentive measures (IMs). We find that NE consists of three dimensions: structural embeddedness, relational embeddedness and functional embeddedness. There is an inverted-U-shaped relationship between structural embeddedness and food waste reduction behaviour, whereas relational embeddedness and functional embeddedness positively correlate with food waste reduction behaviour. Furthermore, IMs significantly strengthen the inverted-U-shaped relationship between NE and food waste reduction behaviour. This article reveals the significance of NE and IMs in influencing FWB, expands the application fields of NE and provides valuable guidance for policymakers to better utilize policy interventions.

2.
Echocardiography ; 41(1): e15737, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38284673

RESUMEN

Half of patients with heart failure are presented with preserved ejection fraction (HFpEF). The pathophysiology of these patients is complex, but increased left ventricular (LV) stiffness has been proven to play a key role. However, the application of this parameter is limited due to the requirement for invasive catheterization for its measurement. With advances in ultrasound technology, significant progress has been made in the noninvasive assessment of LV chamber or myocardial stiffness using echocardiography. Therefore, this review aims to summarize the pathophysiological mechanisms, correlations with invasive LV stiffness constants, applications in different populations, as well as the limitations of echocardiography-derived indices for the assessment of both LV chamber and myocardial stiffness. Indices of LV chamber stiffness, such as the ratio of E/e' divided by left ventricular end-diastolic volume (E/e'/LVEDV), the ratio of E/SRe (early diastolic strain rates)/LVEDV, and diastolic pressure-volume quotient (DPVQ), are derived from the relationship between echocardiographic parameters of LV filling pressure (LVFP) and LV size. However, these methods are surrogate and lumped measurements, relying on E/e' or E/SRe for evaluating LVFP. The limitations of E/e' or E/SRe in the assessment of LVFP may contribute to the moderate correlation between E/e'/LVEDV or E/SRe/LVEDV and LV stiffness constants. Even the most validated measurement (DPVQ) is considered unreliable in individual patients. In comparison to E/e'/LVEDV and E/SRe/LVEDV, indices like time-velocity integral (TVI) measurements of pulmonary venous and transmitral flows may demonstrate better performance in assessing LV chamber stiffness, as evidenced by their higher correlation with LV stiffness constants. However, only one study has been conducted on the exploration and application of TVI in the literature, and the accuracy of assessing LV chamber stiffness remains to be confirmed. Regarding echocardiographic indices for LV myocardial stiffness evaluation, parameters such as epicardial movement index (EMI)/ diastolic wall strain (DWS), intrinsic velocity propagation of myocardial stretch (iVP), and shear wave imaging (SWI) have been proposed. While the alteration of DWS and its predictive value for adverse outcomes in various populations have been widely validated, it has been found that DWS may be better considered as an overall marker of cardiac function performance rather than pure myocardial stiffness. Although the effectiveness of iVP and SWI in assessing left ventricular myocardial stiffness has been demonstrated in animal models and clinical studies, both indices have their limitations. Overall, it seems that currently no echocardiography-derived indices can reliably and accurately assess LV stiffness, despite the development of several parameters. Therefore, a comprehensive evaluation of LV stiffness using all available parameters may be more accurate and enable earlier detection of alterations in LV stiffness.


Asunto(s)
Insuficiencia Cardíaca , Disfunción Ventricular Izquierda , Animales , Humanos , Volumen Sistólico/fisiología , Ecocardiografía , Ventrículos Cardíacos/diagnóstico por imagen , Diástole , Función Ventricular Izquierda , Disfunción Ventricular Izquierda/diagnóstico por imagen
3.
J Environ Manage ; 327: 116848, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36455436

RESUMEN

In the era of internet-based information, how to promote sustainable low-carbon consumption by residents through information incentives and social influence is a pressing question that needs to be solved urgently. This study develops an explanatory model to explain how information incentives and social influence affect sustainable low-carbon consumption by residents. Data were collected from residents by large-scale online surveys in China. Partial least squares (PLS) regression was used to evaluate the model in its theory-mediated model scope to make it better than multiple regression. The empirical results show that purchase behavior, daily use behavior, waste disposal behavior, and public participation behavior define sustainable low-carbon consumption behavior; information incentives and social influence are two important predictors for low-carbon consumption behavior; at the level of information motivation, emotional information has a greater impact on low-carbon consumption behavior than rational information; and at the level of social influence, the influence of peer imitation is greater than that of endorsements and social norms. This study provides interesting insights into the important role of information and social networks for promoting low-carbon consumption behavior. Finally, we propose an information-based guidance policy to promote low-carbon consumption behavior based on social influence.


Asunto(s)
Carbono , Motivación , Emociones , Encuestas y Cuestionarios , Políticas
4.
Cancer Res ; 82(5): 791-804, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-34987057

RESUMEN

ARID1A is a key mammalian SWI/SNF complex subunit that is mutated in 5% to 11% of lung cancers. Although recent studies have elucidated the mechanism underlying dysregulation of the switch/sucrose non-fermentable (SWI/SNF) complexes in cancers, the significance of ARID1A loss and its implications in lung cancers remain poorly defined. This study investigates how ARID1A loss affects initiation and progression of lung cancer. In genetically engineered mouse models bearing mutant Kras and a deficient Trp53 allele (KP), ARID1A loss (KPA) promoted lung tumorigenesis. Analysis of the transcriptome profiles of KP and KPA tumors suggested enhanced glycolysis following ARID1A loss, and expression of the glycolytic regulators Pgam1, pyruvate kinase M (Pkm), and Pgk1 was significantly increased in ARID1A-deficient lung tumors. Furthermore, ARID1A loss increased chromatin accessibility and enhanced hypoxia-inducible factor-1α (HIF1α) binding to the promoter regions of Pgam1, Pkm, and Pgk1. Loss of ARID1A in lung adenocarcinoma also resulted in loss of histone deacetylase 1 (HDAC1) recruitment, increasing acetylation of histone-4 lysine at the promoters of Pgam1, Pkm, and Pgk1, and subsequently enhancing BRD4-driven transcription of these genes. Metabolic analyses confirmed that glycolysis is enhanced in ARID1A-deficient tumors, and genetic or pharmacologic inhibition of glycolysis inhibited lung tumorigenesis in KPA mice. Treatment with the small molecule bromodomain and extraterminal protein (BET) inhibitor JQ1 compromised both initiation and progression of ARID1A-deficient lung adenocarcinoma. ARID1A negatively correlated with glycolysis-related genes in human lung adenocarcinoma. Overall, ARID1A loss leads to metabolic reprogramming that supports tumorigenesis but also confers a therapeutic vulnerability that could be harnessed to improve the treatment of ARID1A-deficient lung cancer. SIGNIFICANCE: This study links ARID1A loss with enhanced glycolysis in lung cancer and demonstrates the preclinical efficacy of BET inhibitor therapy as a strategy to combat tumor growth.


Asunto(s)
Adenocarcinoma del Pulmón , Proteínas de Unión al ADN , Neoplasias Pulmonares , Factores de Transcripción , Adenocarcinoma del Pulmón/genética , Animales , Carcinogénesis/genética , Proteínas de Ciclo Celular/metabolismo , Ensamble y Desensamble de Cromatina , Proteínas de Unión al ADN/genética , Glucólisis/genética , Humanos , Neoplasias Pulmonares/genética , Mamíferos/genética , Mamíferos/metabolismo , Ratones , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Factores de Transcripción/genética
5.
Front Oncol ; 11: 691762, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34367973

RESUMEN

BACKGROUND: Tumor cells initiate hypoxia-induced mechanisms to fuel cell proliferation, invasion, and metastasis, largely mediated by low O2-responsive Hypoxia-Inducible Factor 1 Alpha (HIF-1α). Therefore, hyperbaric oxygen therapy (HBO) is now being studied in cancer patients, but its impact upon non-small-cell lung cancer (NSCLC) cell metabolism remains uncharacterized. METHODS: We employed the NSCLC cell lines A549 and H1299 for in vitro studies. Glucose uptake, pyruvate, lactate, and adenosine triphosphate (ATP) assays were used to assess aerobic glycolysis (Warburg effect). A quantitative glycolytic flux model was used to analyze the flux contributions of HIF-1α-induced glucose metabolism genes. We used a Lewis lung carcinoma (LLC) murine model to measure lung tumorigenesis in C57BL/6J mice. RESULTS: HBO suppressed hypoxia-induced HIF-1α expression and downstream HIF-1α signaling in NSCLC cells. One HIF-1α-induced glucose metabolism gene-Phosphofructokinase, Platelet (PFKP)-most profoundly enhanced glycolytic flux under both low- and high-glucose conditions. HBO suppressed hypoxia-induced PFKP transactivation and gene expression via HIF-1α downregulation. HBO's suppression of the Warburg effect, suppression of hyperproliferation, and suppression of epithelial-to-mesenchymal transition (EMT) in hypoxic NSCLC cell lines is mediated by the HIF-1α/PFKP axis. In vivo, HBO therapy inhibited murine LLC lung tumor growth in a Pfkp-dependent manner. CONCLUSIONS: HBO's repression of the Warburg effect, repression of hyperproliferation, and repression of EMT in hypoxic NSCLC cells is dependent upon HIF-1α downregulation. HIF-1α's target gene PFKP functions as a central mediator of HBO's effects in hypoxic NSCLC cells and may represent a metabolic vulnerability in NSCLC tumors.

6.
Environ Sci Pollut Res Int ; 28(15): 18850-18869, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33586111

RESUMEN

This study proposes a bibliometric measure to visualize and analyze the research status and development trend of carbon offset based on 1,581 articles over the period 1900-2019. The main findings include (1) carbon offset research turned into a rapid growth after 2009; (2) environmental studies, environmental science, economics, and energy fuels are the top four research domains in publication; (3) Energy Policy, Ecological Economics and Science are the top three journals in terms of citation impact; (4) climate change, impact, emission, CO2 emission, and policy are shown to be the most frequently used keywords; (5) the top 10 cited articles cover the following five essential aspects: individual carbon offset behavior; forest and land carbon offset; transportation carbon offset; international trade carbon offset; and eco-system service-related carbon offset; (6) eight research hotspots were identified including forest carbon sequestration program, understanding carbon and uncertainty market, policy design, biomass development, Chinese province, increasing adoption, and ecosystem service commodification. These findings suggest that the carbon offset research has been evolved from the theoretical exploration at the early stage to a more diversified conversion of research outputs at the practical level in recent years. Interdisciplinary research towards individual and organizational carbon offset behaviors in a broader context of socio-economic development and cooperation among various agents is the emphasis and direction for future study.


Asunto(s)
Carbono , Ecosistema , Bibliometría , Comercio , Internacionalidad
7.
Biosens Bioelectron ; 173: 112824, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33229132

RESUMEN

Detection of dysregulated circulating microRNAs (miRNAs) in human biofluids is a fundamental ability to determine tumor occurrence and metastasis in a minimally invasive fashion. However, the requirements for sophisticated instruments and professional personnel impede the translation of miRNA tests into routine clinical diagnostics, especially for resource-limited regions. Herein, we developed a DNA-guided bioluminescence strategy for the detection of circulating miRNAs. In this strategy, a pair of split luciferase-DNA chimeras was constructed and integrated into the miRNA-triggered rolling circle amplification (RCA) process. The tandem reassembly of split luciferase-DNA chimeras on the RCA products elicited a turn-on bioluminescence response with ultrahigh signal-to-background (S/B) ratio. This strategy enabled smartphone-based assays for different miRNAs with attomolar sensitivity and single-base specificity, as demonstrated here for miR-21. miR-148b, and cel-miR-39. Further application of our approach to the clinical serum samples realized identification of dysregulated miR-21 and miR-148b in the lung cancer patients, showing a satisfactory agreement with the control assays performed with quantitative reverse transcription polymerase chain reaction (qRT-PCR). Therefore, the developed method possesses the benefits of high performance and reliability, offering a potential tool for implementing miRNA-based diagnosis in point-of-care (POC) settings.


Asunto(s)
Técnicas Biosensibles , MicroARN Circulante , MicroARNs , Quimera , ADN , Humanos , Luciferasas , MicroARNs/genética , Reproducibilidad de los Resultados , Teléfono Inteligente
8.
Artículo en Inglés | MEDLINE | ID: mdl-33198312

RESUMEN

Inter-regional electricity trade is an important way to mitigate the imbalance between regional electricity generation and consumption. With the increasing amount of inter-regional electricity trade in China, the emission transfer problem is more severe. By using Quasi-Input-Output model, which can consider the ripple effect of electricity trade network, this study analyzed embodied greenhouse gas emissions of electricity trade among 30 provinces in China. Results indicated that, in 2017, the national transfer volumes of CO2, CH4, and N2O embodied in inter-provincial electricity trade were 603.25 Mt, 6803.81 t, and 9899.25 t, respectively. Emissions are mainly transferred from the eastern to the western regions, especially to those with high proportion of electricity generated from fossil fuels. The amount of emission transfer is not consistent with that of purchased electricity, since some regions are rich in clean energy. Although direct emission transfer plays the dominant role for most province, indirect emission transfer should also be noticed. Provinces with larger indirect emission transfer generally purchase electricity from provinces with a lot of electricity inflows. The findings could help policy makers coordinate regional energy utilization strategies and issue more effective emission reduction policies in the electricity industry.


Asunto(s)
Electricidad , Gases de Efecto Invernadero , Industrias , Dióxido de Carbono/análisis , China , Industrias/estadística & datos numéricos
9.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 35(3): 452-459, 2018 06 25.
Artículo en Chino | MEDLINE | ID: mdl-29938955

RESUMEN

With the aging of the society, the number of stroke patients has been increasing year by year. Compared with the traditional rehabilitation therapy, the application of upper limb rehabilitation robot has higher efficiency and better rehabilitation effect, and has become an important development direction in the field of rehabilitation. In view of the current development status and the deficiency of upper limb rehabilitation robot system, combined with the development trend of all kinds of products of the upper limb rehabilitation robot, this paper designed a center-driven upper limb rehabilitation training robot for cable transmission which can help the patients complete 6 degrees of freedom (3 are driven, 3 are underactuated) training. Combined the structure of robot with more joints rehabilitation training, the paper choosed a cubic polynomial trajectory planning method in the joint space planning to design two trajectories of eating and lifting arm. According to the trajectory equation, the movement trajectory of each joint of the robot was drawn in MATLAB. It laid a foundation for scientific and effective rehabilitation training. Finally, the experimental prototype is built, and the mechanical structure and design trajectories are verified.


Asunto(s)
Brazo , Robótica , Rehabilitación de Accidente Cerebrovascular , Brazo/fisiopatología , Humanos , Modalidades de Fisioterapia
10.
J Environ Manage ; 209: 371-381, 2018 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-29309962

RESUMEN

Carbon dioxide embodied flow in international trade has become an important factor in defining global carbon emission responsibility and climate policy. We conducted an empirical analysis for China and Japan for the years 2000-2014, using a multi-region input-output model and considering the rest of the world as a comparison group. We compared the two countries' direct and complete carbon dioxide emissions intensity and bilateral economic activities such as imports and exports, production and consumption to analyze the difference between China and Japan. The results showed that the intensities of carbon emissions in all sectors of China were higher than that in Japan and that China's annual production-based emissions were greater than consumption-based emissions, the opposite of these relationships in Japan. China was a typical net carbon export country, and carbon embodied in its imports and exports continued to increase throughout the study period. In contrast, Japan's volume and growth rate of embodied carbon emissions were far less than China's and Japan was a typical net carbon import country. Finally, the conclusions of this study support recommendations for the formulation of international carbon emission responsibility allocation, domestic abatement policy as well as China's trade policy.


Asunto(s)
Dióxido de Carbono , Internacionalidad , Carbono , China , Clima , Comercio , Japón
11.
Environ Sci Pollut Res Int ; 25(4): 3348-3359, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29151184

RESUMEN

Along with the rapid development of the transportation industry, the problems of the energy crisis and transport emissions have become increasingly serious. The success of traffic emission reduction is related to the realization of global low-carbon goals. Placing priority on public transport is the internationally recognized traffic development model. This paper takes Shanghai, China, as an example to examine the optimal public transport structure. Five factors were selected from personal and public perspectives, including travel costs, crowding degree, occupied area, traffic emissions, and operating subsidies. The objective functions of these factors were transformed into satisfaction functions, and a multi-objective programming model was used to solve for the optimal proportions of the ground bus and rail transit, and the carbon emission reduction potential was analyzed in different scenarios. The study showed that the actual proportion of rail transit in Shanghai was slightly lower than the optimal value, and accompanied by low satisfaction with each factor relative to the optimal value. It was difficult to achieve the traffic emission reduction targets by only reducing satisfaction with other factors except carbon emissions assuming a fixed proportion of public transport. As the proportion of total travel represented by public transport increased, rail transit became the main mode of public transport and the usage trend was more obvious, but the structure of public transport gradually reached a relatively stable state after a certain level of development. Compared to reducing carbon emissions by changing satisfaction with other factors, it was easier to achieve traffic emission reduction targets by increasing the proportion of public transport. To increase the proportion of public transport travel and achieve the goal of traffic reduction in the future, further improvements are needed in the quality of public transport system services, public transport priority development must be differentiated, and the profitability of the public transport industry itself must be enhanced.


Asunto(s)
Contaminación del Aire/análisis , Contaminación del Aire/prevención & control , Transportes/métodos , Transportes/normas , Emisiones de Vehículos/análisis , Emisiones de Vehículos/prevención & control , China , Simulación por Computador , Modelos Teóricos
12.
J Neurosci Res ; 95(12): 2493-2499, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28467619

RESUMEN

Although several donor nerves can be chosen to repair avulsed brachial plexus nerve injury, available nerves are still limited. The purpose of this study is to validate whether the vagus nerve (VN) can be used as a donor. Eighteen Sprague-Dawley male rats were divided into three groups (n = 6). The right musculocutaneous nerve (McN) was transected with differing subsequent repair. (1) HS-VN group: a saphenous nerve (SN) graft-end was helicoidally wrapped round the VN side (epi-and perineurium was opened) with a 30 ° angle, distal SN end was coapted to the McN with end-to-end repair. (2) EE-PN group: a SN was interpositionally grafted between the transected phrenic nerve (PN) and the McN by end-to-end coaptation. (3) Sham control group: McN was transected and not repaired and postoperative vital signs were checked daily. At three months, electrophysiology, tetanic force, wet biceps muscle weight, and histology were evaluated. Every tested mean value in HS-VN group was significantly greater than the EE-PN or the sham control groups (p < 0.05 or p < 0.005). The mean recovery ratio of regenerated nerve fibers was 96% and, in HS-VN group, the mean recovery ratio of CMAP was 79%. No vital signs changed in any group. There was no statistical difference (p > 0.5) between the mean VN nerve-fiber numbers of the segments proximal (2237 ± 134) and distal (2150 ± 156) to the VN graft-attachment site. Histological analysis revealed no axon injury or intraneural scarring at any point along the VN. This study demonstrated that VN is a practical and reliable donor nerve for end-to-side nerve transfer. © 2017 Wiley Periodicals, Inc.


Asunto(s)
Nervio Musculocutáneo/cirugía , Transferencia de Nervios/métodos , Nervio Vago/trasplante , Animales , Regeneración Nerviosa/fisiología , Ratas , Ratas Sprague-Dawley
13.
J Reconstr Microsurg ; 33(6): 435-440, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28293917

RESUMEN

Background After peripheral nerve injury, there is an increase in calcium concentration in the injured nerves. Our previous publications have shown that increase in calcium concentration correlated well with degree of nerve injury and that local infusion of calcitonin has a beneficial effect on nerve recovery. Schwann cells play a pivotal role in regeneration and recovery. We aim to examine cultured Schwann cell survivals in various concentrations of calcium-containing growth media and the effect of calcitonin in such media. Methods To establish baseline in postinjury state, crush injury was induced in male Sprague-Dawley rats' sciatic nerves. Extra- and intraneural calcium concentrations were measured. To study Schwann cell survival, uninjured sciatic nerve segment was harvested and cultured in media containing various amounts of calcium. To study the effect of calcitonin, nerve harvest and culture were done in four additional media: (1) normal control, (2) normal control with calcitonin, (3) high calcium medium, and (4) high calcium medium with calcitonin. Schwann cells were studied and analyzed under fluorescent conditions. Results With increasing calcium concentration, there was a significant decrease in the number of Schwann cells. For the experimental groups, in which calcitonin had been added to the growth medium, there were similar amounts of Schwann cells present in both high and low calcium-containing medium. Conclusion Schwann cells are sensitive to increasing calcium concentration. Calcitonin counteracts the detrimental effects of high calcium on Schwann cell survival. This can have significant future clinical implications for patients with peripheral nerve injuries.


Asunto(s)
Calcio/metabolismo , Regeneración Nerviosa/efectos de los fármacos , Células de Schwann/citología , Células de Schwann/efectos de los fármacos , Nervio Ciático/lesiones , Nervio Ciático/metabolismo , Animales , Conservadores de la Densidad Ósea/farmacología , Calcitonina/farmacología , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Modelos Animales de Enfermedad , Masculino , Compresión Nerviosa , Regeneración Nerviosa/fisiología , Ratas , Ratas Sprague-Dawley , Recuperación de la Función , Nervio Ciático/efectos de los fármacos , Nervio Ciático/fisiopatología
14.
J Neurosci Res ; 95(9): 1786-1795, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28052373

RESUMEN

Peripheral nerve injury can have a devastating effect on daily life. Calcium concentrations in nerve fibers drastically increase after nerve injury, and this activates downstream processes leading to neuron death. Our previous studies showed that calcium-modulating agents decrease calcium accumulation, which aids in regeneration of injured peripheral nerves; however, the optimal therapeutic window for this application has not yet been identified. In this study, we show that calcium clearance after nerve injury is positively correlated with functional recovery in rats suffering from a crushed sciatic nerve injury. After the nerve injury, calcium accumulation increased. Peak volume is from 2 to 8 weeks post injury; calcium accumulation then gradually decreased over the following 24-week period. The compound muscle action potential (CMAP) measurement from the extensor digitorum longus muscle recovered to nearly normal levels in 24 weeks. Simultaneously, real-time polymerase chain reaction results showed that upregulation of calcium-ATPase (a membrane protein that transports calcium out of nerve fibers) mRNA peaked at 12 weeks. These results suggest that without intervention, the peak in calcium-ATPase mRNA expression in the injured nerve occurs after the peak in calcium accumulation, and CMAP recovery continues beyond 24 weeks. Immediately using calcium-modulating agents after crushed nerve injury improved functional recovery. These studies suggest that a crucial time frame in which to initiate effective clinical approaches to accelerate calcium clearance and nerve regeneration would be prior to 2 weeks post injury. © 2017 Wiley Periodicals, Inc.


Asunto(s)
Calcitonina/farmacología , Bloqueadores de los Canales de Calcio/farmacología , Calcio/metabolismo , Nifedipino/farmacología , Traumatismos de los Nervios Periféricos/metabolismo , Recuperación de la Función/fisiología , Animales , Masculino , Compresión Nerviosa , Regeneración Nerviosa/efectos de los fármacos , Regeneración Nerviosa/fisiología , Ratas , Ratas Sprague-Dawley
15.
Muscle Nerve ; 56(4): 768-772, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27997687

RESUMEN

INTRODUCTION: After nerve injury, calcium concentrations in intranerve fibers quickly increase. We have shown that functional recovery of injured nerves correlates with calcium absorption. A slight increase in calcium reduces the number of Schwann cells present. Calcitonin therapy greatly improves regeneration by accelerating calcium absorption. We examined the effect of adding calcitonin to higher concentration calcium media on cultured Schwann cells. METHODS: The cells, isolated from intact sciatic nerves, were cultured with normal or higher concentration calcium media with or without calcitonin. Schwann cells were incubated with anti-S-100, goat-anti-mouse, and propidium iodide and then viewed through fluorescent light and phase-contrast microscopy for observation and analysis. RESULTS: The cells in each calcitonin-containing medium showed many Schwann cells, however, the cells in the higher concentration calcium media showed fewer and more defective Schwann cells. CONCLUSION: These results show that calcitonin protects against the harmful effects of excessive calcium encountered in peripheral nerve injury. Muscle Nerve 56: 768-772, 2017.


Asunto(s)
Calcitonina/farmacología , Calcio/metabolismo , Células de Schwann/efectos de los fármacos , Células de Schwann/metabolismo , Animales , Conservadores de la Densidad Ósea/farmacología , Calcio/farmacología , Células Cultivadas , Masculino , Ratas , Ratas Sprague-Dawley
16.
J Reconstr Microsurg ; 32(3): 222-5, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26636887

RESUMEN

BACKGROUND: Study of peripheral nerve injury and regeneration in laboratory animals can be time consuming and expensive. This study determines if it is possible to reduce time and cost for a peripheral nerve regeneration study. PURPOSE: The purpose of this study was to determine if nerve axonal area (NXA) or nerve fiber counting (NFC) correlates with compound muscle action potential (CMAP) recovery which is known to predict functional muscular recovery in the early stage of nerve regeneration. METHODS: In this study, six rats had a crush injury of the sciatic nerve without treatment. These rats were evaluated at 4 weeks of recovery with the following assessments: CMAP readings from the extensor digitorum longus, NXA measurement, and NFC. RESULTS: NXA correlated with CMAP; NFC did not correlate with CMAP. CONCLUSION: NFC is not a reliable method for predicting muscular recovery in the early stages. NXA is a dependable assessment for muscular recovery in the early stages of nerve regeneration. Using NXA measurement can predict later electrophysiological and functional recovery. Using NXA with CMAP measurement for nerve injury, repair, and treatment in the animal study can save cost and time.


Asunto(s)
Regeneración Nerviosa/fisiología , Traumatismos de los Nervios Periféricos/fisiopatología , Nervio Ciático/lesiones , Potenciales de Acción , Animales , Modelos Animales de Enfermedad , Masculino , Compresión Nerviosa , Fibras Nerviosas/ultraestructura , Ratas , Ratas Sprague-Dawley , Recuperación de la Función/fisiología
17.
J Stroke Cerebrovasc Dis ; 24(12): 2759-73, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26433438

RESUMEN

BACKGROUND: Insidious cumulative brain injury from motor vehicle-induced whole-body vibration (MV-WBV) has not yet been studied. The objective of the present study is to validate whether whole-body vibration for long periods causes cumulative brain injury and impairment of the cerebral function. We also explored a preventive method for MV-WBV injury. METHODS: A study simulating whole-body vibration was conducted in 72 male Sprague-Dawley rats divided into 9 groups (N = 8): (1) 2-week normal control; (2) 2-week sham control (in the tube without vibration); (3) 2-week vibration (exposed to whole-body vibration at 30 Hz and .5 G acceleration for 4 hours/day, 5 days/week for 2 weeks; vibration parameters in the present study are similar to the most common driving conditions); (4) 4-week sham control; (5) 4-week vibration; (6) 4-week vibration with human apolipoprotein A-I molecule mimetic (4F)-preconditioning; (7) 8-week sham control; (8) 8-week vibration; and (9) 8-week 4F-preconditioning group. All the rats were evaluated by behavioral, physiological, and histological studies of the brain. RESULTS: Brain injury from vibration is a cumulative process starting with cerebral vasoconstriction, squeezing of the endothelial cells, increased free radicals, decreased nitric oxide, insufficient blood supply to the brain, and repeated reperfusion injury to brain neurons. In the 8-week vibration group, which indicated chronic brain edema, shrunken neuron numbers increased and whole neurons atrophied, which strongly correlated with neural functional impairment. There was no prominent brain neuronal injury in the 4F groups. CONCLUSIONS: The present study demonstrated cumulative brain injury from MV-WBV and validated the preventive effects of 4F preconditioning.


Asunto(s)
Lesiones Encefálicas/tratamiento farmacológico , Péptidos/uso terapéutico , Vibración , Accidentes de Tránsito , Animales , Lesiones Encefálicas/prevención & control , Masculino , Ratas , Ratas Sprague-Dawley
18.
J Reconstr Microsurg ; 31(8): 551-7, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26125148

RESUMEN

BACKGROUND: Histological analysis remains a cornerstone approach for the investigation of peripheral nerve regeneration. This study investigates a newly recognized histological difference between peripheral and central zones within the regenerating nerve trunks. PURPOSE: The purpose of the study was to determine if the nerve axonal area (NXA) in regenerating peripheral nerves differs within central and peripheral areas, when viewed in cross-section. METHODS: A total of 14 rats were divided into two groups, and subjected to different injuries to the right sciatic nerve. Group 1: Transection injury with immediate repair. Group 2: Crush injury without any treatment. The left sciatic nerve was left uninjured and served as a control in each rat. Following 4 weeks of recovery, nerve trunk cross-sections were prepared. Computerized techniques were then employed to divide nerve sections into central and peripheral zones and calculate corresponding NXA values for subsequent statistical analysis. RESULTS: NXA of injured nerves was greater within peripheral as compared with the central zones, independent of injury type (p < 0.05). No statistically significant difference existed within the control groups or between the injury methods with regards to NXA regeneration extent. CONCLUSION: NXA in regenerating peripheral nerves was greater in the peripheral zones than within the central zones.


Asunto(s)
Axones/patología , Regeneración Nerviosa/fisiología , Traumatismos de los Nervios Periféricos/patología , Traumatismos de los Nervios Periféricos/cirugía , Nervio Ciático/patología , Animales , Biopsia con Aguja , Modelos Animales de Enfermedad , Inmunohistoquímica , Masculino , Procedimientos Neuroquirúrgicos/métodos , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Procedimientos de Cirugía Plástica/métodos , Medición de Riesgo , Nervio Ciático/lesiones , Nervio Ciático/cirugía , Resultado del Tratamiento
19.
J Neurosci Res ; 93(5): 736-44, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25557339

RESUMEN

Insidious brain microinjury from motor vehicle-induced whole-body vibration (WBV) has not yet been investigated. For a long time we have believed that WBV would cause cumulative brain microinjury and impair cerebral function, which suggests an important risk factor for motor vehicle accidents and secondary cerebral vascular diseases. Fifty-six Sprague-Dawley rats were divided into seven groups (n = 8): 1) 2-week normal control group, 2) 2-week sham control group (restrained in the tube without vibration), 3) 2-week vibration group (exposed to whole-body vibration at 30 Hz and 0.5g acceleration for 4 hr/day, 5 days/week, for 2 weeks), 4) 4-week sham control group, 5) 4-week vibration group, 6) 8-week sham control group, and 7) 8-week vibration group. At the end point, all rats were evaluated in behavior, physiological, and brain histopathological studies. The cerebral injury from WBV is a cumulative process starting with vasospasm squeezing of the endothelial cells, followed by constriction of the cerebral arteries. After the 4-week vibration, brain neuron apoptosis started. After the 8-week vibration, vacuoles increased further in the brain arteries. Brain capillary walls thickened, mean neuron size was obviously reduced, neuron necrosis became prominent, and wide-ranging chronic cerebral edema was seen. These pathological findings are strongly correlated with neural functional impairments.


Asunto(s)
Enfermedades del Sistema Nervioso/etiología , Enfermedades del Sistema Nervioso/patología , Vibración/efectos adversos , Análisis de Varianza , Animales , Corteza Cerebral/patología , Modelos Animales de Enfermedad , Suspensión Trasera , Masculino , Aprendizaje por Laberinto/fisiología , Microscopía Electrónica de Transmisión , Arteria Cerebral Media/patología , Arteria Cerebral Media/ultraestructura , Fuerza Muscular/fisiología , Conducción Nerviosa/fisiología , Neuronas/patología , Óxido Nítrico/metabolismo , Oxígeno/metabolismo , Dimensión del Dolor , Ratas , Ratas Sprague-Dawley
20.
Muscle Nerve ; 51(2): 229-34, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24809806

RESUMEN

INTRODUCTION: After nerve injury, excessive calcium impedes nerve regeneration. We previously showed that calcitonin improved nerve regeneration in crush injury. We aimed to validate the direct effect of calcitonin on transected and repaired nerve. METHODS: Two rat groups (n = 8) underwent sciatic nerve transection followed by direct repair. In the calcitonin group, a calcitonin-filled mini-osmotic pump was implanted subcutaneously, with a catheter parallel to the repaired nerve. The control group underwent repair only, without a pump. Evaluation and comparison between the groups included: (1) compound muscle action potential recording of the extensor digitorum longus (EDL) muscle; (2) tetanic muscle force test of EDL; (3) nerve calcium concentration; and (4) nerve fiber count and calcified spot count. RESULTS: The calcitonin pump group showed superior recovery. CONCLUSIONS: Calcitonin affects injured and repaired peripheral nerve directly. The calcitonin-filled mini-osmotic pump improved nerve functional recovery by accelerating calcium absorption from the repaired nerve. This finding has potential clinical applications.


Asunto(s)
Calcitonina/administración & dosificación , Bombas de Infusión Implantables , Regeneración Nerviosa/efectos de los fármacos , Neuropatía Ciática/tratamiento farmacológico , Potenciales de Acción/efectos de los fármacos , Animales , Calcio/metabolismo , Modelos Animales de Enfermedad , Electromiografía , Colorantes Fluorescentes , Fuerza Muscular/efectos de los fármacos , Músculo Esquelético/fisiopatología , Fibras Nerviosas/patología , Ratas , Ratas Sprague-Dawley , Neuropatía Ciática/patología , Factores de Tiempo , Cicatrización de Heridas/efectos de los fármacos
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