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1.
Zhongguo Zhong Yao Za Zhi ; 48(5): 1176-1185, 2023 Mar.
Artigo em Zh | MEDLINE | ID: mdl-37005801

RESUMO

Salvianolic acid B(Sal B) is the main water-soluble component of Salvia miltiorrhiza Bunge. Studies have found that Sal B has a good protective effect on blood vessels. Sal B can protect endothelial cells by anti-oxidative stress, inducing autophagy, inhibiting endoplasmic reticulum stress(ERS), inhibiting endothelial inflammation and adhesion molecule expression, inhibiting endothelial cell permeability, anti-thrombosis, and other ways. In addition, Sal B can alleviate endothelial cell damage caused by high glucose(HG). For vascular smooth muscle cell(VSMC), Sal B can reduce the synthesis and secretion of inflammatory factors by inhibiting cyclooxygenase. It can also play a vasodilatory role by inhibiting Ca~(2+) influx. In addition, Sal B can inhibit VSMC proliferation and migration, thereby alleviating vascular stenosis. Sal B also inhibits lipid deposition in the subendothelium, inhibits macrophage conversion to foam cells, and reduces macrophage apoptosis, thereby reducing the volume of subendothelial lipid plaques. For some atherosclerosis(AS) complications, such as peripheral artery disease(PAD), Sal B can promote angiogenesis, thereby improving ischemia. It should be pointed out that the conclusions obtained from different experiments are not completely consistent, which needs further research. In addition, previous pharmacokinetics showed that Sal B was poorly absorbed by oral administration, and it was unstable in the stomach, with a large first-pass effect in the liver. Sal B had fast distribution and metabolism in vivo and short drug action time. These affect the bioavailability and biological effects of Sal B, and the development of clinically valuable Sal B non-injectable delivery systems remains a great challenge.


Assuntos
Benzofuranos , Células Endoteliais , Estresse Oxidativo , Benzofuranos/farmacologia , Lipídeos
2.
J Environ Manage ; 316: 115208, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35550957

RESUMO

A modified sodium bentonite geosynthetic clay liner (GCL) designed for acid-and-alkaline resistance was evaluated for its potential application in the containment of bauxite residue leachate. A modified fluid loss test was employed to quickly evaluate the hydraulic conductivity (k) of the GCL using distilled water, tap water, and four bauxite liquors (BLs, leachate from bauxite residue reservoirs). The effects of swelling capacity of bentonite, prehydration, hydraulic gradient (i), ionic strength (I), and relative abundance of monovalent and multivalent cations (RMD) on the hydraulic conductivity of the GCL were analyzed. The results indicated that the BLs significantly decreased free swell index of the bentonite. As compared to increasing i, prehydration obviously enhanced hydraulic performance of the GCL. The four BLs increased k of the GCL by a factor of 4-12 relative to the tap water permeation condition, and the resultant k exceeded upper limit of 5.0 × 10-11 m/s for GCLs. The increase in k was attributed to compression in diffuse double layer of the bentonite and dissolution in clay minerals in ion-rich and hyperalkaline BLs, manifesting that further modification on the GCL is needed. The I was found a better indicator than the RMD on correlation with chemical compatibility of the GCL.


Assuntos
Bentonita , Eliminação de Resíduos , Óxido de Alumínio , Silicatos de Alumínio , Argila , Eliminação de Resíduos/métodos , Água
3.
Neural Plast ; 2021: 9912686, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34194489

RESUMO

Microglia-mediated neuroinflammation is one of the most remarkable hallmarks of neurodegenerative diseases (NDDs), including AD, PD, and ALS. Accumulating evidence indicates that microglia play both neuroprotective and detrimental roles in the onset and progression of NDDs. Yet, the specific mechanisms of action surrounding microglia are not clear. Modulation of microglia function and phenotypes appears to be a potential strategy to reverse NDDs. Until recently, research into the epigenetic mechanisms of diseases has been gradually developed, making it possible to elucidate the molecular mechanisms underlying the epigenetic regulation of microglia in NDDs. This review highlights the function and phenotypes of microglia, elucidates the relationship between microglia, epigenetic modifications, and NDDs, as well as the possible mechanisms underlying the epigenetic modulation of microglia in NDDs with a focus on potential intervention strategies.


Assuntos
Epigênese Genética , Microglia/fisiologia , Doenças Neurodegenerativas/genética , Metilação de DNA , Código das Histonas , Humanos , Doenças Neuroinflamatórias/genética , Doenças Neuroinflamatórias/patologia , Fenótipo
4.
Int J Neuropsychopharmacol ; 22(1): 57-70, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30407508

RESUMO

Background: Hyperhomocysteinemia is an independent risk factor for dementia, including Alzheimer's disease. Lowering homocysteine levels with folic acid treatment with or without vitamin B12 has shown few clinical benefits on cognition. Methods: To verify the effect of emodin, a naturally active compound from Rheum officinale, on hyperhomocysteinemia-induced dementia, rats were treated with homocysteine injection (HCY, 400 µg/kg/d, 2 weeks) via vena caudalis. Afterwards, HCY rats with cognitive deficits were administered intragastric emodin at different concentrations for 2 weeks: 0 (HCY-E0), 20 (HCY-E20), 40 (HCY-E40), and 80 mg/kg/d (HCY-E80). Results: ß-Amyloid overproduction, tau hyperphosphorylation, and losses of neuron and synaptic proteins were detected in the hippocampi of HCY-E0 rats with cognitive deficits. HCY-E40 and HCY-E80 rats had better behavioral performance. Although it did not reduce the plasma homocysteine level, emodin (especially 80 mg/kg/d) reduced the levels of ß-amyloid and tau phosphorylation, decreased the levels of ß-site amyloid precursor protein-cleaving enzyme 1, and improved the activity of protein phosphatase 2A. In the hippocampi of HCY-E40 and HCY-E80 rats, the neuron numbers, levels of synaptic proteins, and phosphorylation of the cAMP responsive element-binding protein at Ser133 were increased. In addition, depressed microglial activation and reduced levels of 5-lipoxygenase, interleukin-6, and tumor necrosis factor α were also observed. Lastly, hyperhomocysteinemia-induced microangiopathic alterations, oxidative stress, and elevated DNA methyltransferases 1 and 3ß were rescued by emodin. Conclusions: Emodin represents a novel potential candidate agent for hyperhomocysteinemia-induced dementia and Alzheimer's disease-like features.


Assuntos
Demência/tratamento farmacológico , Demência/etiologia , Emodina/farmacologia , Hiper-Homocisteinemia/complicações , Hiper-Homocisteinemia/tratamento farmacológico , Nootrópicos/farmacologia , Peptídeos beta-Amiloides/metabolismo , Animais , Transtornos Cognitivos/tratamento farmacológico , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/metabolismo , Transtornos Cognitivos/patologia , Metilação de DNA/efeitos dos fármacos , Metilação de DNA/fisiologia , Demência/metabolismo , Demência/patologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Hipocampo/patologia , Hiper-Homocisteinemia/metabolismo , Hiper-Homocisteinemia/patologia , Masculino , Microglia/efeitos dos fármacos , Microglia/metabolismo , Microglia/patologia , Microvasos/efeitos dos fármacos , Microvasos/metabolismo , Microvasos/patologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Distribuição Aleatória , Ratos Sprague-Dawley , Proteínas tau/metabolismo
5.
Neural Plast ; 2019: 6856327, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31093272

RESUMO

Tau hyperphosphorylation is a typical pathological change in Alzheimer's disease (AD) and is involved in the early onset and progression of AD. Epigenetic modification refers to heritable alterations in gene expression that are not caused by direct changes in the DNA sequence of the gene. Epigenetic modifications, such as noncoding RNA regulation, DNA methylation, and histone modification, can directly or indirectly affect the regulation of tau phosphorylation, thereby participating in AD development and progression. This review summarizes the current research progress on the mechanisms of epigenetic modification associated with tau phosphorylation.


Assuntos
Doença de Alzheimer/genética , Epigênese Genética , Neurônios/metabolismo , Proteínas tau/genética , Animais , Metilação de DNA , Código das Histonas , Humanos , Fosforilação , RNA não Traduzido/genética , Transdução de Sinais
6.
J Environ Manage ; 146: 179-188, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25173726

RESUMO

Cement stabilization is used extensively to remediate soils contaminated with heavy metals. However, previous studies suggest that the elevated zinc (Zn) and lead (Pb) concentrations in the contaminated soils would substantially retard the cement hydration, leading to the deterioration of the performance of cement stabilized soils. This study presents a new binder, KMP, composed of oxalic acid-activated phosphate rock, monopotassium phosphate and reactive magnesia. The effectiveness of stabilization using this binder is investigated on soils spiked with Zn and Pb, individually and together. Several series of tests are conducted including toxicity characteristic leaching (TCLP), ecotoxicity in terms of luminescent bacteria test and unconfined compressive strength. The leachability of a field Zn- and Pb- contaminated soil stabilized with KMP is also evaluated by TCLP leaching test. The results show that the leached Zn concentrations are lower than the China MEP regulatory limit except when Zn and Pb coexist and for the curing time of 7 days. On the other hand, the leached Pb concentrations for stabilized soils with Pb alone or mixed Zn and Pb contamination are much lower than the China MEP or USEPA regulatory limit, irrespective of the curing time. The luminescent bacteria test results show that the toxicity of the stabilized soils has been reduced considerably and is classified as slightly toxic class. The unconfined compressive strength of the soils decrease with the increase in the Zn concentration. The stabilized soils with mixed Zn and Pb contaminants exhibit notably higher leached Zn concentration, while there is lower unconfined compressive strength relative to the soils when contaminated with Zn alone. The X-ray diffraction and scanning electron microscope analyses reveal the presence of bobierrite (Mg3(PO4)2·8H2O) and K-struvite (MgKPO4·6H2O) as the main products formed in the KMP stabilized uncontaminated soils; the formation of hopeite (Zn3(PO4)2·4H2O), scholzite (CaZn2(PO4)2·2H2O), zinc hydroxide (Zn(OH)2), and fluoropyromorphite (Pb5(PO4)3F) in the soils are the main mechanisms for immobilization of Zn and Pb with the KMP binder. The change in the relative quantities of the formed phosphate-based products, with respect to the Zn concentration and presence of mixed Zn and Pb contaminants, can well explain the measured impact of the Zn concentration levels and presence of both Zn and Pb contaminants on the unconfined compressive strength of the KMP stabilized soils.


Assuntos
Metais Pesados/química , Poluentes do Solo/química , Solo/química , Humanos , Chumbo/química , Fosfatos/química , Zinco/química
7.
Chempluschem ; : e202400247, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38803293

RESUMO

The potential of acetylene is extremely high both in chemical industry and synthetic applications due to unsaturated nature and the smallest C≡C unit. The production of many essential necessities is originated from acetylene; however, the formation of acetylene molecule requires a lot of energy. Currently, the access to acetylene is based on coal processing, methane reforming and calcium carbide hydrolysis. Recently, extensive research has been done to decrease the cost of acetylene. In this review, the routes to acetylene were highlighted, considering the energy consumption in kW/t of the product to evaluate the best approach. Since energy prices depend on various regions, the cost of the product is complicated. The manufacturing of acetylene is usually accompanied by formation of by-products, which may be valuable or not. The review should help to identify current status and not overlook promising approaches.

8.
Sci Total Environ ; 917: 170421, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38286291

RESUMO

Leachate comprising organic contaminants such as dichloromethane is frequently discharged into groundwater at contaminated sites and unlined landfills. Soil-bentonite backfills in vertical cutoff walls are extensively employed to contain the flow of contaminated groundwater, thereby safeguarding the downstream groundwater environmental quality and ecosystem. This study presented a comprehensive evaluation of effects of dichloromethane-impacted groundwater on hydraulic conductivity and microscopic characteristics of soil-bentonite backfills amended with polymer namely polyanionic cellulose and microscale zero-valent iron. The results showed the amended backfills exhibited lower hydraulic conductivity than the unamended backfill regardless of the permeant type, i.e., tap water and dichloromethane solution. Scanning electron microscopy coupled with energy-dispersive spectrometry analyses demonstrated that polyanionic cellulose hydrogel could effectively coat sand, bentonite, and microscale zero-valent iron particles, providing protection of bentonite particles against attacks imposed by the dichloromethane and multivalent iron ions, and diminish aggregation of microscale zero-valent iron particles in the amended backfills. X-ray diffraction results indicated there was no intercalation of polyanionic cellulose and microscale zero-valent iron into the montmorillonite platelets of bentonite particles. Based on the Fourier Transform Infrared Spectroscopy Spectra analysis, a new functional group (-CH2) was identified on the polyanionic cellulose amended bentonite particles. The results demonstrated that amendment with polyanionic cellulose and microscale zero-valent iron is a promising approach to improve the performance of soil-bentonite backfills in containing flow of dichloromethane-impacted groundwater.

9.
J Vis Exp ; (207)2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38801269

RESUMO

Thread-embedding therapy (TEAT) is a treatment that prevents and manages diseases by inserting a biodegradable suture into an acupoint, providing long-lasting stimulation. TEAT is a simple approach that avoids the discomfort of regular acupuncture and provides sustained therapeutic effects. This article discusses the potential impact of TEAT on the learning and memory abilities of rats with Alzheimer's disease-like symptoms. Since chemically induced neuronal degeneration and cognitive impairments in rats does not entirely reflect the true pathological changes observed in Alzheimer's disease. Consequently, our research group has designated these manifestations as Alzheimer's disease-like symptoms. A protocol has been established to outline the selection of acupoints, the operation process, and necessary precautions for the head and lower back. The experiment was conducted on three groups: a control group, a model group, and a TEAT group, each containing 6 rats. To induce Alzheimer's disease-like symptoms, rats were intraperitoneally injected with D-galactose for 7 weeks (49 days). The rats in the TEAT group received acupoint catgut embedding treatment. Following the intervention period, a Morris Water Maze (MWM) was conducted to evaluate the rats' learning and memory. Subsequently, the rats were sacrificed, and their brain tissue was examined. A histological examination was performed to understand the effects of TEAT on the pathology of rats exhibiting symptoms of Alzheimer's disease. This study suggests that TEAT may improve learning and memory in rats with Alzheimer's disease-like symptoms, indicating a potentially promising new treatment approach for this neurodegenerative condition.


Assuntos
Terapia por Acupuntura , Doença de Alzheimer , Animais , Doença de Alzheimer/terapia , Terapia por Acupuntura/métodos , Ratos , Modelos Animais de Doenças , Pontos de Acupuntura , Suturas , Masculino , Ratos Sprague-Dawley , Aprendizagem em Labirinto/fisiologia
10.
J Vis Exp ; (206)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38738896

RESUMO

Compared to filiform needle therapy, fire-needle therapy has both the stimulation of needles and the warming effect of heat, making it have unexpected effects on some chronic diseases and incurable diseases. Osteoporosis (OP) has a high incidence in postmenopausal women and middle-aged and elderly men, and the treatment cycle is long. According to Traditional Chinese Medicine (TCM), Lingnan fire-needle therapy has shown potential in treating osteoporosis. However, there is still a long way to go before it can be widely used. This article focuses on the application of Lingnan fire-needle therapy in the intervention of OP in rats. It covers the selection of needle tools, acupuncture point selection, positioning of rats' bodies, and fixation methods. We also outline the steps and precautions to be taken during and after needling with fire needles. The experiment was done with three groups: a normal group, a model group, and a fire-needle group, each containing 10 rats. The rats in the fire-needle group were treated with fire-needle intervention for six sessions. After the intervention period, we collected femoral specimens and performed micro-CT scans. The results suggest that fire needling can enhance bone morphology and mineral density in OP rats. This information can serve as a methodological basis for conducting basic research on fire-needle therapy.


Assuntos
Terapia por Acupuntura , Modelos Animais de Doenças , Osteoporose , Animais , Ratos , Osteoporose/terapia , Feminino , Terapia por Acupuntura/métodos , Terapia por Acupuntura/instrumentação , Ratos Sprague-Dawley , Agulhas , Medicina Tradicional Chinesa/métodos , Masculino
11.
Zhonghua Yi Xue Za Zhi ; 93(34): 2699-702, 2013 Sep 10.
Artigo em Zh | MEDLINE | ID: mdl-24360100

RESUMO

OBJECTIVE: To evaluate the human health risks (premature death risk as an indicator) in Beijing, Shanghai, Guangzhou and Xi'an during extreme haze in January 2013. METHODS: The daily average particulate matter ≤ 2.5 µm in aerodynamic diameter (PM2.5) concentrations of Beijing, Shanghai, Guangzhou and Xi'an in January 2013 were collected and their characteristics explored. The populations and mortality rate of four cities in 2010 were collected from the statistical yearbook, the exposure-response relationships selected from the reference and then the premature death calculated according to the proportion risk model of Poisson regression. RESULTS: In January 2013, the 24 h mean concentrations of PM2.5 in Beijing, Shanghai, Guangzhou and Xi'an were (240 ± 165) , (83 ± 27), (94 ± 49) and (210 ± 98) µg/m(3) respectively and they were all above the secondary level of Ambient Air Quality Standards (GB 3095-2012). The 24 h mean concentrations of PM2.5 in Beijing and Xi'an were much higher than those in Shanghai and Guangzhou. Approximately 86.4% (19/22) , 58.1% (18/31), 54.8% (17/31) and 93.5% (29/31) of 24 h mean PM2.5 concentrations in Beijing, Shanghai, Guangzhou and Xi'an respectively exceeded the secondary level of Ambient Air Quality Standards (GB 3095-2012). The number of premature death due to the exposure to haze were 725 (95%CI: 457-977) for Beijing, 296 (95%CI: 96-502) for Shanghai, 310 (95%CI: 189-434) for Guangzhou and 85 (95%CI: 21-141) for Xi'an respectively in January 2013. CONCLUSION: The PM2.5 pollutions of four cities in January 2013 were serious enough to pose elevated risks of human health.


Assuntos
Poluição do Ar/efeitos adversos , Exposição Ambiental/efeitos adversos , China , Cidades , Humanos , Material Particulado/efeitos adversos , Medição de Risco
12.
Zhen Ci Yan Jiu ; 48(2): 133-8, 2023 Feb 25.
Artigo em Zh | MEDLINE | ID: mdl-36858408

RESUMO

OBJECTIVE: To observe the effect of electroacupuncture (EA) at "Baihui"(GV20) and "Shenshu" (BL23) on the pathological injury of neurons in SAMP8 mice and the anti-inflammatory effect on neuron repair, providing a new experimental basis for EA prevention and treatment of Alzheimer's disease. METHODS: Twelve 7-month-old SAMP8 mice were randomly divided into model and EA groups, and 6 SAMR1 mice of the same age and genetic background were used as normal group. Mice in the EA group were needled at GV20 and bilateral BL23, and EA (1 mA, 2 Hz) was applied to bilateral BL23 for 15 min, once daily, 10 d as a course for a total of 4 courses, with an interval of 1 d. Mice in the normal and model groups were captured and fixed in the same way as the EA group. The spatial learning and memory ability was detected by Morris water maze test. Neuronal nuclear antigen (NeuN) positive expression and the number of NeuN-positive cells in dentate gyrus (DG) were detected by immunofluorescence staining. The protein expression levels of ionized calcium binding adapter molecule 1(Iba-1), tumor necrosis factor-α(TNF-α), interleukin (IL)-6 and IL-1ß in hippocampus were detected by Western blot. The ultrastructure of nerve cells in DG was observed by transmission electron microscopy. RESULTS: Compared with the normal group, the average escape latency was prolonged(P<0.01), the number of platform crossing was significantly reduced (P<0.01), the average fluorescence intensity of NeuN and the number of NeuN-positive cells in hippocampus DG region decreased (P<0.05), the expression levels of Iba-1, TNF-α, IL-6 and IL-1ß in hippocampus were increased (P<0.05) in the model group.Compared with the model group, the ave-rage escape latency was shortened (P<0.01), the number of platform crossing times was significantly increased (P<0.01), the average fluorescence intensity of NeuN and the number of NeuN-positive cells in hippocampus DG region increased (P<0.05), the expression levels of Iba-1, TNF-α, IL-6 and IL-1ß in hippocampus were decreased (P<0.05) in the EA group. The morphology of nerve cells in the hippocampus DG region was normal, and the organelles in the cytoplasm were clear, complete and regularly distributed in the normal group. However, the morphology of nerve cells in the model group was seriously irregular, which was also irregular in EA group but somewhat relieved compared with model group. CONCLUSION: EA at GV20 and BL23 can improve the learning and memory ability of SAMP8 mice, which may be related to inhibiting the neuroinflammatory response, increasing the number of neurons and improving the ultrastructure of the DG region of the hippocampus to play the role of neuron protection.


Assuntos
Eletroacupuntura , Animais , Camundongos , Interleucina-6 , Fator de Necrose Tumoral alfa , Hipocampo , Neurônios
13.
J Vis Exp ; (198)2023 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-37607089

RESUMO

In basic experimental acupuncture research, rats are commonly used as laboratory animals. However, it is difficult for them to maintain a fixed posture. During electroacupuncture procedures, proper immobilization of rats is essential. Various methods of rat fixation are currently used, including anesthesia fixation, high-platform fixation, binding fixation, and fixation with a self-made rat coat. However, these methods have their limitations, which may affect the efficiency and operability of the experiment to some extent. This protocol introduces a method of suspending and fixing rats using rat clothes. Firstly, rats are clothed with rat jackets that match their body shape, taking advantage of their preference for darkness and burrowing. The needling operation can then be carried out after the rats have worn rat clothes. When suspended, the rats are relatively still, as their limbs cannot move. This fixation method offers not only economical and user-friendly benefits but also ensures a stable and reliable fixation of the rats in a comfortably relaxed position. It also effectively minimizes time consumption, experimental space, and manpower resources. Additionally, this method allows for the exposure of most acupoints used for acupuncture in rats. This article primarily concentrates on the device's composition, encompassing a specially designed rat jacket, an elevated fixation rack, and their connecting structures. Additionally, an illustrative example will be presented to demonstrate the application of the rat clothing-based suspension fixation method in rat electroacupuncture procedures.


Assuntos
Terapia por Acupuntura , Anestesia , Animais , Ratos , Pontos de Acupuntura , Extremidades , Técnicas Histológicas , Suspensões
14.
Mar Environ Res ; 183: 105829, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36495654

RESUMO

The rapidly growing concern of marine microplastic pollution has drawn attentions globally. Microplastic particles are normally subjected to visual characterization prior to more sophisticated chemical analyses. However, the misidentification rate of current visual inspection approaches remains high. This study proposed a state-of-the-art deep learning-based approach, Mask R-CNN, to locate, classify, and segment large marine microplastic particles with various shapes (fiber, fragment, pellet, and rod). A microplastic dataset including 3000 images was established to train and validate this Mask R-CNN algorithm, which was backboned by a Resnet 101 architecture and could be tuned in less than 8 h. The fully trained Mask R-CNN algorithm was compared with U-Net in characterizing microplastics against various backgrounds. The results showed that the algorithm could achieve Precision = 93.30%, Recall = 95.40%, F1 score = 94.34%, APbb (Average precision of bounding box) = 92.7%, and APm (Average precision of mask) = 82.6% in a 250 images test dataset. The algorithm could also achieve a processing speed of 12.5 FPS. The results obtained in this study implied that the Mask R-CNN algorithm is a promising microplastic characterization method that can be potentially used in the future for large-scale surveys.


Assuntos
Aprendizado Profundo , Microplásticos , Plásticos , Poluição Ambiental , Velocidade de Processamento
15.
Artigo em Inglês | MEDLINE | ID: mdl-35742497

RESUMO

Compacted clay covers (CCCs) are effective in restricting the upward migration of volatile organic compound (VOC) and semi-volatile organic compound (SVOC) vapors released mainly from unsaturated contaminated soils and hence mitigate the risks to human health. Desiccation cracking of CCCs would result in numerous preferential channels. VOC or SVOC vapors can prefereially migrate through the cracks and emit into the atmosphere, exposing threats to human health and surrounding environmental acceptors. This study presented results of comprehensive field investigation of desiccation crack distribution in CCCs, where four herbaceous plants were covered at the industrial contaminated site in. The plants included Trefoil, Bermuda grass, Conyza Canadensis, and Paspalum, and the corresponding planting areas were labeled as S1, S2, S3, and S4, respectively. The quantity and geometry parameters of the cracks including crack width, depth, and length, were investigated. The results showed that the cracks of the CCCs were mainly distributed in the areas of S3 (Conyza Canadensis) and S4 (Paspalum), where more cracks were formed when the degree of compaction (DOC) of the CCCs was less than 87%. In addition, the results revealed that: (1) no cracks were found in the area S1 (Trefoil); (2) the quantity, average width, average depth, average length, and maximal length of the cracks in the investigated areas followed S4 (Paspalum) > S3 (Conyza Canadensis) > S2 (Bermuda grass); (3) the maximal crack length in the area S2 (Bermuda grass) was the shortest, which was approximately one-seventh and one-eighth of those in the areas S3 (Conyza Canadensis) and S4 (Paspalum), respectively; and (4) the maximal width and depth of the cracks followed S3 (Conyza Canadensis) > S4 (Paspalum) > S2 (Bermuda grass).


Assuntos
Conyza , Compostos Orgânicos Voláteis , Atmosfera , Argila , Humanos , Plantas , Compostos Orgânicos Voláteis/farmacologia
16.
Environ Sci Pollut Res Int ; 29(8): 11393-11404, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34537940

RESUMO

Decreasing carbon emissions by replacing Portland cement (PC) with supplementary cementitious materials (SCMs), such as low-grade limestone (LS) and calcined clays (CC), has tremendous potential for stabilization/solidification (S/S) of industrial hazardous waste primarily with heavy metals. Recently, a low-carbon-based cementitious binder, namely, limestone calcined clay cement (LC), has emerged as an alternative for S/S treatment of wastes. However, comprehensive comparison between LC and PC application in solidifying/stabilizing wastes has not been conducted. This study aims to investigate the S/S efficiency of Pb-Zn smelter residue (LZSR) comprising heavy metals lead (Pb), zinc (Zn), and cadmium (Cd) at higher concentrations. LZSR is treated with LC and PC for capturing strength and leaching toxicity. The test results indicate that low-grade CC and LS in the LC binder can promote the alkaline environment, and act as fillers in solidifying heavy metals. The toxicity characteristic leaching procedure leaching concentrations of untreated (UT) LZSR were 503 mg/kg, 1266 mg/kg, and 251 mg/kg for Pb, Zn, and Cd, respectively. After a 28-day curing, the leaching concentrations in LC-treated LZSR reduced to 4.33 mg/kg, 189.68 mg/kg, and 0.46 mg/kg, while the leaching concentrations of PC-treated LZSR reduced to 29 mg/kg, 338 mg/kg, and 6 mg/kg for Pb, Zn, and Cd, respectively. The maximum immobilization efficiencies for Pb, Zn, and Cd reached 85%, 99%, and 99%, respectively. Moreover, the insoluble phases for Pb, Zn, and Cd obtained from the sequential extraction test results were 63.5%, 72.1%, and 42.4% for LC-treated LZSR and 35.7%, 38%, and 43% for PC-treated LZSR with binder content of 8% binder and curing time of 28 days. Increasing curing time and binder content reduced leaching concentrations, and the underneath mechanisms were interpreted by XRD, SEM-EDS, and FTIR analyses. Overall, the results indicate that Pb, Zn, and Cd can be successfully immobilized using 8% LC binder by transforming soluble heavy metals to insoluble hydroxides and their complexes.


Assuntos
Metais Pesados , Zinco , Carbonato de Cálcio , Argila , Chumbo , Metais Pesados/análise
17.
Aging Dis ; 13(4): 1092-1105, 2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35855345

RESUMO

Due to global population aging and modern lifestyle changes, the incidence of central nervous system (CNS) disorders, such as neurodegenerative diseases, neuropsychiatric disorders, and cerebrovascular diseases, is increasing and has become a major public health challenge. Current medications commonly used in the clinic are far from satisfactory and may cause serious side effects. Therefore, the identification of novel drugs for the effective management of CNS diseases is very urgent. Puerarin, a highly bioactive ingredient isolated from Pueraria lobata, is known to possess a broad spectrum of pharmacological properties including anti-diabetic, anti-inflammatory, anti-antioxidant, neuroprotective, and cardioprotective features. However, its clinical application is limited due to its poor water solubility. Since puerarin has demonstrated a wide range of neuroprotective functions in various CNS diseases, such as Alzheimer's disease, Parkinson's disease, cerebral ischemia, depression, and spinal cord injury, it has been attracting increasingly intense attention worldwide. In this review, we intend to extensively summarize the research progress on neuroprotective mechanisms of puerarin in recent years and discuss the future directions of its application in CNS disease treatment.

18.
Aging Dis ; 13(6): 1733-1744, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36465168

RESUMO

Ischemic stroke is a major cause of mortality and neurological morbidity worldwide. The underlying pathophysiology of ischemic stroke is highly complicated and correlates with various pathological processes, including neuroinflammation, oxidative stress injury, altered cell apoptosis and autophagy, excitotoxicity, and acidosis. The current treatment for ischemic stroke is limited to thrombolytic therapy such as recombinant tissue plasminogen activator. However, tissue plasminogen activator is limited by a very narrow therapeutic time window (<4.5 hours), selective efficacy, and hemorrhagic complication. Hence, the development of novel therapies to prevent ischemic damage to the brain is urgent. Chinese herbal medicine has a long history in treating stroke and its sequela. In the past decades, extensive studies have focused on the neuroprotective effects of Huanglian Jie Du decoction (HLJDD), an ancient and classical Chinese herbal formula that can treat a wide spectrum of disorders including ischemic stroke. In this review, the current evidence of HLJDD and its bioactive components for ischemic stroke is comprehensively reviewed, and their potential application directions in ischemic stroke management are discussed.

19.
Sci Total Environ ; 848: 157646, 2022 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-35907534

RESUMO

Ex-situ stabilization for As and Sb co-contaminated soil was conducted through an iron-based stabilizer, PFSC (a mixture of polymerized ferric sulfate (PFS) and hydrated lime (Ca(OH2)) with a dry mass ratio of 2:1). After field aging for one week, the stabilized contaminated soil was subjected to a horizontal vibration leaching test (HJ 557), Wenzel's sequential extraction, and a semi-dynamic leaching test (ANS 16.1). By assessing the cumulative fractions of As and Sb, the observed diffusion coefficients (Dobs) and leachability indices (LX) of metalloids released from the soil specimens were calculated. The PFSC ex-situ stabilization was effective to immobilize metalloids, and the As and Sb leached concentrations of stabilized contaminated soil samples were lower than remediation targets. Nonspecifically bound As and Sb in the stabilized contaminated soil samples decreased from 4.5 - 9.2 % to 1.5-2.5 % and from 2.2 - 5.8 % to 1.1-1.5 %, respectively. The mechanisms controlling the leaching behaviors of As and Sb included wash-off and diffusion and they were changed with the leaching interval. The mean Dobs of As and Sb released from stabilized contaminated soil specimen were 3.46 × 10-12 and 2.99 × 10-13 cm2 s-1, in the which were two orders of magnitude lower than that of untreated contaminated soil specimen. The mean LX of stabilized contaminated soil specimen for As and Sb releases were 11.40 and 12.83, respectively, indicating that the stabilized contaminated soil was acceptable for "controlled utilization".


Assuntos
Arsênio , Poluentes do Solo , Antimônio , Arsênio/análise , Ferro , Solo , Poluentes do Solo/análise
20.
Front Endocrinol (Lausanne) ; 12: 632324, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33868169

RESUMO

Obesity is a prevalent metabolic disease caused by an imbalance in food intake and energy expenditure. Although acupuncture is widely used in the treatment of obesity in a clinical setting, its mechanism has not been adequately elucidated. As the key pivot of appetite signals, the hypothalamus receives afferent and efferent signals from the brainstem and peripheral tissue, leading to the formation of a complex appetite regulation circuit, thereby effectively regulating food intake and energy homeostasis. This review mainly discusses the relationship between the hypothalamic nuclei, related neuropeptides, brainstem, peripheral signals, and obesity, as well as mechanisms of acupuncture on obesity from the perspective of the hypothalamus, exploring the current evidence and therapeutic targets for mechanism of action of acupuncture in obesity.


Assuntos
Terapia por Acupuntura , Ingestão de Alimentos/fisiologia , Metabolismo Energético/fisiologia , Hipotálamo/metabolismo , Obesidade/terapia , Homeostase/fisiologia , Humanos , Obesidade/metabolismo
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