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1.
Curr Med Chem ; 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38644710

RESUMO

BACKGROUND: Glaucoma is an eye disease. Its pathological process involves retinal ischemia-reperfusion (I/R), which causes irreversible blindness in patients. Geniposide (Gen), a bioactive iridoid glycoside extracted from the fruit of gardenia, exhibits many biological effects, such as anti-oxidative stress, anti-inflammation, anti-apoptosis, anti-endoplasmic reticulum stress, and anti-thrombotic effects. However, its therapeutic potential for the retinal I/R injury remains unclear. This study investigated the protective effect of Gen against I/R injury by inhibiting abnormal reactive oxygen species (ROS) and retinal neuron apoptosis. METHODS: We used oxygen-glucose deprivation/reoxygenation (OGD/R) to induce R28 cells to mimic the pathological process of I/R in glaucoma. We conducted CCK-8 analysis and TUNEL staining to examine cell proliferation and apoptosis in glaucoma. Western blotting was used to assay the expressions of apoptosis and Akt/Nrf-2 pathway-related proteins. RESULTS: The production of ROS was detected by using the corresponding kit. Cell viability decreased, whereas TUNEL staining-positive cells and ROS production increased after the OGD/R injury. The contents of cleaved caspase-3 and Bax/Bcl-2 increased after the OGD/R injury. Treatment with 200 µM of Gen effectively improved the cell viability and suppressed cell apoptosis and ROS production. In addition, Gen could significantly promote the activation of the Akt/Nrf-2 signaling pathway in R28 cells, which was blocked by the inhibition of Akt/Nrf-2. We in vivo verified the neuroprotective effect of Gen by establishing an acute high intraocular pressure (aHIOP) model and obtained similar results to those of the in vitro experimental results. CONCLUSION: Hence, it can be suggested that Gen provides neuroprotection against the OGD/R-induced injury of R28 cells by activating the Akt/Nrf-2 signaling pathway, which is beneficial for the clinical treatment of glaucoma.

2.
Phys Chem Chem Phys ; 25(31): 20794-20807, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37465860

RESUMO

Foam-like NiMo coatings were produced from an inexpensive mixture of Ni, Al, and Mo powders via atmospheric plasma spraying. The coatings were deposited onto stainless-steel meshes forming a highly porous network mainly composed of nanostructured Ni and highly active Ni4Mo. High material loading (200 mg cm-2) with large surface area (1769 cm2 per cm2) was achieved without compromising the foam-like characteristics. The coatings exhibited excellent activity towards both hydrogen evolution (HER) and oxygen evolution (OER) reactions in alkaline media. The HER active coating required an overpotential of 42 mV to reach a current density of -50 mA cm-2 with minimum degradation after a 24 h chronoamperometry test at -10 mA cm-2. Theoretical simulations showed that several crystal surfaces of Ni4Mo exhibit near optimum hydrogen adsorption energies and improved water dissociation that benefit the HER activity. The OER active coating also consisting of nanostructured Ni and Ni4Mo required only 310 mV to achieve a current density of 50 mA cm-2. The OER activity was maintained even after 48 h of continuous operation. We envisage that the development of scalable production techniques for Ni4Mo alloys will greatly benefit its usage in commercial alkaline water electrolysers.

3.
Int J Occup Saf Ergon ; 29(3): 1147-1159, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35968640

RESUMO

This study empirically tested the relationship between sub-dimensions of employees' lean construction (LC) competence and construction safety performance (SP), while incorporating organizational LC competence as a mediator. Data were collected from 710 employees on 300 construction projects. The hypothesis model was validated using multiple regression analysis. The results show that employees' cognitive competence can positively influence construction SP both directly and indirectly via organizational LC competence. However, employees' social competence had a direct negative effect on construction SP, but it can have an indirect positive effect on construction SP via organizational LC competence. Coincidentally, employees' continuous improvement competence had no direct effect on construction SP, but it can have an indirect positive impact via organizational LC competence. This article clarifies the definition of LC competence and empirically validates its influence on construction SP, enriching LC management theory and guiding managers on how to improve construction SP in LC practice.


Assuntos
Indústria da Construção , Saúde Ocupacional , Cultura Organizacional , Humanos
4.
Nanomaterials (Basel) ; 12(23)2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36500758

RESUMO

One-dimensional tellurium nanostructures can exhibit distinct electronic properties from those seen in bulk Te. The electronic properties of nanostructured Te are highly dependent on their morphology, and thus controlled synthesis processes are required. Here, highly crystalline tellurium nanowires were produced via physical vapour deposition. We used growth temperature, heating rate, flow of the carrier gas, and growth time to control the degree of supersaturation in the region where Te nanostructures are grown. The latter leads to a control in the nucleation and morphology of Te nanostructures. We observed that Te nanowires grow via the vapour-solid mechanism where a Te particle acts as a seed. Transmission electron microscopy (TEM) and electron diffraction studies revealed that Te nanowires have a trigonal crystal structure and grow along the (0001) direction. Their diameter can be tuned from 26 to 200 nm with lengths from 8.5 to 22 µm, where the highest aspect ratio of 327 was obtained for wires measuring 26 nm in diameter and 8.5 µm in length. We investigated the use of bismuth as an additive to reduce the formation of tellurium oxides, and we discuss the effect of other growth parameters.

5.
Neuropsychiatr Dis Treat ; 17: 2257-2267, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34285486

RESUMO

INTRODUCTION: The study aimed to explore the effects of treatment with black bamboo rhizome extracts on learning and memory and determine the underlying mechanisms in rats with cerebral ischaemia-reperfusion injury. METHODS: Sprague-Dawley rats were randomly divided into the following four groups: control, middle cerebral artery occlusion (MCAO), low-dose drug, and high-dose drug groups. Rats underwent MCAO using a suture method before drug treatment. Then, neurological impairment was assessed using the Longa scoring method, and triphenyl tetrazolium chloride staining was used to analyse the cerebral infarction area. The Elliott formula was used to calculate water content in the brain tissue. A Morris water maze (MWM) was used to assess changes in learning and memory abilities, and Western blotting was used to detect cyclic adenosine phosphate response element-binding protein (CREB) and brain-derived neurotrophic factor (BDNF) expression in the hippocampus of MCAO rats. RESULTS: After treatment with black bamboo rhizome extracts, the neurological dysfunction score was lower in the drug groups than in the MCAO group, and a significant difference was observed between the high-dose drug and MCAO groups (P<0.05). Additionally, the cerebral infarction area was significantly smaller in the drug groups than in the MCAO group (P<0.01), and the effect was more obvious in the high-dose drug group than in the low-dose drug group. There was also a significant difference in water content between the high-dose drug and MCAO groups, and cerebral oedema was significantly reduced in the high-dose drug group (P<0.05). In the MWM, the incubation period was significantly reduced, the number of platform crossings was significantly increased, and the search time was prolonged in the drug groups compared with those in the MCAO group (P<0.05). Moreover, the expression of BDNF and CREB was significantly increased in the drug groups compared to that in the MCAO group, and the increase was more obvious in the high-dose group than in the low-dose group (P<0.05). DISCUSSION: Black bamboo rhizome extracts significantly improved cognitive dysfunction, reduced cerebral oedema, decreased the cerebral infarction area, and improved the neurological function score and learning and memory abilities in rats with cerebral ischaemia-reperfusion injury.

6.
Adv Ther ; 38(7): 4130-4137, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34160757

RESUMO

INTRODUCTION: The gold standard surgical therapy for patients with clinical stage I non-small cell lung cancer (NSCLC) is lobectomy with mediastinal lymph node dissection. Meanwhile, segmentectomy has emerged as an alternative choice with the advantage of fewer postoperative complications. The acceptance of this procedure remains controversial, and conflicting results exist in the retrospective trials. OBJECTIVES: The aim of this meta-analysis was to analyze the survival outcomes of lobectomy versus segmentectomy in clinical stage I NSCLC. METHODS: A computerized literature search was done on published trials in PubMed, Embase, and the Cochrane Library to June 2019 to identify clinical trials. Lung cancer-specific survival (LCSS) and overall survival (OS) were measured as outcomes. Statistical analysis was performed in the Meta-analysis Revman 5.3 software. RESULTS: A systematic literature search was conducted including seven studies. In this meta-analysis, the LCSS and OS in the lobectomy group were linked to a markedly lower trend in comparison to the segmentectomy group without significant statistical difference (P > 0.05), indicating that lobectomy confers an equivalent survival outcome compared with segmentectomy. CONCLUSION: No significant differences were found in survival outcomes between lobectomy and segmentectomy. Further large-scale, prospective, randomized trials are needed to explore reasonable surgical treatments for early-stage lung cancer.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Estadiamento de Neoplasias , Pneumonectomia , Estudos Prospectivos , Estudos Retrospectivos
7.
CNS Neurol Disord Drug Targets ; 20(3): 228-248, 2021 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-32744977

RESUMO

Ischemic neuronal injury results from a complex series of pathophysiological events, including oxidative, excitotoxicity, inflammation and nitrative stress. Consequently, many of these events can induce cell death, including necrosis (unregulated cell death) and apoptosis (a type of regulated cell death). These are long-established paradigms to which newly discovered regulated cell death processes have been added, such as necroptosis (a regulated form of necrosis) and autophagydependent cell death. Moreover, many researchers have targeted products associated with Chinese herbal medicine at regulated pathways for the treatment of ischemic neuronal injury. In East Asia, these drugs have been known for centuries to protect and improve the nervous system. Herbal extracts, especially those used in Chinese herbal medicine, have emerged as new pharmaceuticals for the treatment of ischemic neuronal injury. Here, we review the evidence from preclinical studies investigating the neuroprotective properties and therapeutic application of Chinese herbal medicines (Chinese herbal monomer, extract, and medicinal compounds) and highlight the potential mechanisms underlying their therapeutic effects via targeting differently regulated cell death pathways. Notably, many herbs have been shown to target multiple mechanisms of regulated cell death and, in combination, may exert synergistic effects on signaling pathways, thereby attenuating multiple aspects of ischemic pathology. In this review, we summarize a generally regulated pathway of cell death as a target for novel natural herbal regimens against ischemic neuronal injury.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Medicina Tradicional Chinesa/métodos , Morte Celular Regulada/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Humanos , Inflamação/tratamento farmacológico , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Transdução de Sinais/efeitos dos fármacos
8.
Biopreserv Biobank ; 18(1): 10-13, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32069099

RESUMO

In the past 10 years, clinical biobanks have experienced increasing expansion in China. Demand for systematically educated biobanking professionals is a priority for Chinese biobanks' agenda. The cryobiology and biobankology course is the first semester-long course in China, designed and developed at Central South University with international cooperation. Leading professors were from China, the United States, United Kingdom, and Canada to teach the latest version of biobanking knowledge and skills around the globe. This course is a comprehensive elective course with six specific teaching modules, which is suitable for graduate students majoring in basic medical sciences, clinical medicine, life sciences, mechanical engineering, and biomedical engineering, who would like to seek biobanking careers in the future. Participants from China, Czech Republic, Ghana, Madagascar, Tanzania, South Sudan, and Israel attended the course. Through taking this course, students can broaden their international academic horizons and cultivate the ability to learn and apply the knowledge of biology, medicine, and engineering to analyze and explain the low-temperature biology and clinical samples-based research practice. At the same time, the course enables students to realize the importance of multidisciplinary fields of biobanking and the significance of innovative precision medicine research, and further enlightens students' enthusiasm to pursue biobanking professional careers, and in the future they can proudly call themselves "biobankers."


Assuntos
Bancos de Espécimes Biológicos/organização & administração , Criobiologia/educação , Educação de Pós-Graduação/métodos , China , Currículo , Humanos , Cooperação Internacional , Mídias Sociais
9.
Surg Radiol Anat ; 42(2): 103-110, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31440808

RESUMO

PURPOSE: To reconstruct the three-dimensional safe triangle areas at L1-5 based on the computed tomography digital data, analyze the safe scopes for the puncture location and angles, and provide anatomic references for percutaneous lumbar discectomy. METHODS: Computed tomography data from patients and control group were imported from the database and anatomical reference parameters were measured in Mimics software. The rebuilt model was rotated clockwise along the M-axis to measure the inscribed circle radius of the safe triangle at different angles. Based on the outer diameter of the largest cannula, the safe angles were calculated. The distances between points on the projection of safe triangle-inscribed circle and the upper lumbar spinous process were measured. Similarly, while the safe triangle was on the left side, the model was contra-rotated to measure all the parameters. RESULTS: There was no significant difference between the patient and control group in both the least distance between the selected anatomical reference locations and the safe triangle-inscribed circle radius at L4-5. According to the series which had a largest cannula of 2.5 mm, the safe puncture angles increased with the descending disc levels. The optimal angles were 40°-45° for L1-2, 45°-50° for L2-3, 50° for L3-4, and 55° for L4-5 separately. The differences between genders in the distances of paired reference points were significant. CONCLUSIONS: Individual safe localization of the percutaneous puncture could be obtained by analyzing the three-dimensional relationship between the puncture localization and anatomical landmarks.


Assuntos
Discotomia Percutânea/efeitos adversos , Imageamento Tridimensional , Complicações Intraoperatórias/prevenção & controle , Vértebras Lombares/irrigação sanguínea , Vértebras Lombares/inervação , Adulto , Idoso , Simulação por Computador , Discotomia Percutânea/métodos , Feminino , Humanos , Deslocamento do Disco Intervertebral/cirurgia , Complicações Intraoperatórias/etiologia , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Masculino , Pessoa de Meia-Idade , Modelos Anatômicos , Nervos Espinhais/lesões , Tomografia Computadorizada por Raios X
10.
Artigo em Inglês | MEDLINE | ID: mdl-30646628

RESUMO

Lean construction has been viewed as an effective management approach for reducing the occurrence of no-value or destructive activities, such as wasting resources and safety-related accidents. However, few studies have systematically addressed how and to what extent lean construction practices influence construction safety. To bridge this gap, a conceptual model is developed and validated using a system dynamics approach. The construction system in this model comprises four sub-systems (i.e., environment system, equipment system, management system, and employee system). Data were collected from 448 projects in China. Simulations were conducted to determine the correlations between five types of lean tools and the four construction sub-systems. The results show that: (a) 5S management has significant positive impacts on the control of key locations and facilities at construction sites, and contributes to the mitigation of environmental impacts; (b) visual management can significantly improve safety compliance and safety management; (c) just-in-time management has significantly positive influences on the safety facilities layout and formulation of the safety plan; and (d) the Last Planner® System and conference management are effective in improving safety training and the implementation of the safety plan. These findings provide new insights into the use of lean construction for improving construction safety through the implementation of a targeted lean approach.


Assuntos
Indústria da Construção/normas , Gestão da Segurança/métodos , China , Humanos , Modelos Teóricos , Local de Trabalho
11.
CNS Neurosci Ther ; 20(1): 20-31, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23937638

RESUMO

BACKGROUND: Demyelination is one of the most important pathological factors of spinal cord injury. Oligodendrocyte apoptosis is involved in triggering demyelination. However, fewer reports on pathological changes and mechanism of demyelination have been presented from compressed spinal cord injury (CSCI). The relative effect of oligodendrocyte apoptosis on CSCI-induced demyelination and the mechanism of apoptosis remain unclear. AIMS: In this study, a custom-designed model of CSCI was used to determine whether or not demyelination and oligodendrocyte apoptosis occur after CSCI. The pathological changes in axonal myelinated fibers were investigated by osmic acid staining and transmission electron microscopy. Myelin basic protein (MBP), which is used in myelin formation in the central nervous system, was detected by immunofluorescence and Western blot assays. Oligodendrocyte apoptosis was revealed by in situ terminal-deoxytransferase-mediated dUTP nick-end labeling. To analyze the mechanism of oligodendrocyte apoptosis, we detected caspase-12 [a representative of endoplasmic reticulum (ER) stress], cytochrome c (an apoptotic factor and hallmark of mitochondria), and inhibitor of DNA binding 2 (Id2, an oligodendrocyte lineage gene) by immunofluorescence and Western blot assays. RESULTS: The custom-designed model of CSCI was successfully established. The rats were spastic, paralyzed, and incontinent. The Basso, Beattie, and Bresnahan (BBB) locomotor rating scale scores were decreased as time passed. The compressed spinal cord slices were ischemic. Myelin sheaths became swollen and degenerative; these sheaths were broken down as time passed after CSCI. MBP expression was downregulated after CSCI and consistent with the degree of demyelination. Oligodendrocyte apoptosis occurred at 1 day after CSCI and increased as caspase-12 expression was enhanced and cytochrome c was released. Id2 was distributed widely in the white matter. Id2 expression increased with time after CSCI. CONCLUSION: Demyelination occurred after CSCI and might be partly caused by oligodendrocyte apoptosis, which was positively correlated with ER-mitochondria interactions and enhanced Id2 expression after CSCI in rats.


Assuntos
Apoptose/fisiologia , Doenças Desmielinizantes/fisiopatologia , Proteína 2 Inibidora de Diferenciação/metabolismo , Oligodendroglia/fisiologia , Organelas/fisiologia , Compressão da Medula Espinal/fisiopatologia , Animais , Axônios/fisiologia , Axônios/ultraestrutura , Western Blotting , Caspase 12/metabolismo , Citocromos c/metabolismo , Doenças Desmielinizantes/etiologia , Doenças Desmielinizantes/patologia , Retículo Endoplasmático/fisiologia , Retículo Endoplasmático/ultraestrutura , Imunofluorescência , Marcação In Situ das Extremidades Cortadas , Isquemia/etiologia , Isquemia/patologia , Isquemia/fisiopatologia , Vértebras Lombares , Microscopia Eletrônica de Transmissão , Mitocôndrias/fisiologia , Mitocôndrias/ultraestrutura , Proteína Básica da Mielina/metabolismo , Oligodendroglia/ultraestrutura , Organelas/ultraestrutura , Ratos , Ratos Sprague-Dawley , Compressão da Medula Espinal/complicações , Compressão da Medula Espinal/patologia
12.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 45(6): 919-23, 2014 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-25571715

RESUMO

OBJECTIVE: To investigate the effect of electroacupuncture on the expression of oligodendrocyte precursor cells in rats with compressed spinal cord injury (CSCI) and to explore the mechanism of remyelinization. METHODS: Thirty-six SD rats were randomly divided into a control group and three treatment groups with 3 d, 7 d and 14 d of treatment respectively. Acupuncture was given to rats in the treatment groups through jiaji point, double zusanli (ST36), and double taixi (KI3). Electroacupuncture (continuous wave, 2 Hz/1. 5 V, 30 min) was applied for the double zusanli (ST36) and double taixi (KI3). Ethological alterations of the rats were observed with quantitative assessment of neurologic function. The ultrastructure changes of nerve fibers in white matter were determined under electronic microscope. Expressions of NG2 protein, an OPC marker, was observed by Western blot. RESULTS: No significant changes in neurologic function and G-ratio were observed after three days and seven days of electroacupuncture treatment (P>0. 05). However, 14 d of electroacupuncture treatment made a significant change compared to the 7 d treatment group and the control group (P<0. 05). The electronic microscope showed axons with varied degree of swollen, degenerated and lost cell organelle in axoplasm, edema in myelin sheaths, disordered, thickened and even broken layers of myelin sheaths in the rats with CSCI. The rats in the treatment groups had milder swollen axons and more compacted layers of myelin sheaths compared to their controls. Western blot showed that the expression of NG2 was increased with time and the differences among the three treatment groups were statistically significant (P<0. 05). The rats in the treatment groups also had higher expressions of NG2 than their controls at 7 d and 14 d (P<0. 05). CONCLUSION: Electroacupuncture can improve inflammation and edema in the injured nerve fibers and up regulate NG2 expression and remyelination of the injured nerve fibers in rats with CSCI.


Assuntos
Eletroacupuntura , Oligodendroglia/citologia , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/terapia , Animais , Ratos , Ratos Sprague-Dawley , Compressão da Medula Espinal
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