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1.
ACS Biomater Sci Eng ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38950519

RESUMO

Large bone defects resulting from fractures and diseases have become a significant medical concern, usually impeding spontaneous healing through the body's self-repair mechanism. Calcium phosphate (CaP) bioceramics are widely utilized for bone regeneration, owing to their exceptional biocompatibility and osteoconductivity. However, their bioactivities in repairing healing-impaired bone defects characterized by conditions such as ischemia and infection remain limited. Recently, an emerging bioceramics zinc-strontium phosphate (ZSP, Zn2Sr(PO4)2) has received increasing attention due to its remarkable antibacterial and angiogenic abilities, while its plausible biomedical utility on tissue regeneration is nonetheless few. In this study, gallic acid-grafted gelatin (GGA) with antioxidant properties was injected into hydrogels to scavenge reactive oxygen species and regulate bone microenvironment while simultaneously incorporating ZSP to form GGA-ZSP hydrogels. The GGA-ZSP hydrogel exhibits low swelling, and in vitro cell experiments have demonstrated its favorable biocompatibility, osteogenic induction potential, and ability to promote vascular regeneration. In an in vivo bone defect model, the GGA-ZSP hydrogel significantly enhanced the bone regeneration rates. This study demonstrated that the GGA-ZSP hydrogel has pretty environmentally friendly therapeutic effects in osteogenic differentiation and massive bone defect repair.

2.
Nat Commun ; 15(1): 1725, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38409087

RESUMO

According to the Montreal Protocol, the production and consumption of ozone-layer-depleting CCl4 for dispersive applications was globally phased out by 2010, including China. However, continued CCl4 emissions were disclosed, with the latest CCl4 emissions unknown in eastern China. In the current study, based on the atmospheric measurements of ~12,000 air samples taken at two sites in eastern China, the 2021-2022 CCl4 emissions are quantified as 7.6 ± 1.7 gigagrams per year. This finding indicates that CCl4 emissions continued after being phased out for dispersive uses in 2010. Subsequently, our study identifies potential industrial sources (manufacture of general purpose machinery and manufacture of raw chemical materials, and chemical products) of CCl4 emissions.

3.
Artigo em Inglês | MEDLINE | ID: mdl-37239556

RESUMO

Volatile organic compounds (VOCs) are major indoor air pollutants that contain several toxic substances. However, there are few studies on health risk assessments of indoor VOCs in China. This study aimed to determine the concentration characteristics of VOCs on college campuses by collecting VOC samples from different locations on campus during different seasons combined with the exposure times of college students in each location obtained from a questionnaire survey to assess the possible health risks. The highest total VOC concentration (254 ± 101 µg/m3) was in the dormitory. The seasonal variation of TVOC concentrations was related to the variation of emission sources in addition to temperature. Health risk assessments of VOCs were evaluated using non-carcinogenic and carcinogenic risk values, represented by hazard quotient (HQ) and lifetime cancer risk (LCR), respectively. The non-carcinogenic risks at all sampling sites were within the safe range (HQ < 1). Dormitories had the highest carcinogenic risk, whereas the carcinogenic risk in the other three places was low (with LCR < 1.0 × 10-6). Moreover, 1,2-dichloroethane was identified as a possible carcinogenic risk substance in the dormitory due to its high LCR (1.95 × 10-6). This study provides basic data on health risks in different locations on campus and a basis for formulating measures to improve people's living environments.


Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Neoplasias , Compostos Orgânicos Voláteis , Humanos , Monitoramento Ambiental , Compostos Orgânicos Voláteis/análise , Universidades , Poluentes Atmosféricos/análise , Medição de Risco , Carcinógenos/análise , Carcinogênese , China/epidemiologia , Poluição do Ar em Ambientes Fechados/análise
4.
Environ Sci Ecotechnol ; 14: 100228, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36560957

RESUMO

Methyl halides (CH3Cl, CH3Br, and CH3I) are ozone-depleting substances. Biomass burning (BB) is an important source of methyl halides. The temporal variations and global spatial distribution of BB methyl halide emissions are unclear. Thus, global methyl halide emissions from BB during 2003-2021 were estimated based on satellite data. A significant decreasing trend (p < 0.01) in global methyl halide emissions from BB was found between 2003 and 2021, with CH3Cl emissions decreasing from 302 to 220 Gg yr-1, CH3Br emissions decreasing from 16.5 to 11.7 Gg yr-1, and CH3I emissions decreasing from 8.9 to 6.1 Gg yr-1. From a latitudinal perspective, the northern high-latitude region (60-90° N) was the only latitude zone with significant increases in BB methyl halide emissions (p < 0.01). Based on an analysis of the drivers of BB methyl halide emissions, emissions from cropland, grassland, and shrubland fires were more correlated with the burned area, while BB emissions from forest fires were more correlated with the emissions per unit burned area. The non-BB emissions of CH3Cl increased from 4749 Gg yr-1 in 2003 to 4882 Gg yr-1 in 2020, while those of CH3Br decreased from 136 Gg yr-1 in 2003 to 118 Gg yr-1 in 2020 (global total CH3I emissions are not available). The finding indicates that global CH3Cl and CH3Br emissions from sources besides BB increased and decreased during 2003-2020. Based on our findings, not only searching for unknown sources is important, but also re-evaluating known sources is necessary for addressing methyl halide emissions.

5.
Sci Total Environ ; 865: 160894, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36563752

RESUMO

In recent years, eastern China has been identified as an important contributor to national and global emissions of halocarbons, some of which are ozone depletion substances (ODSs) that delay the recovery of the stratospheric ozone layer. However, the most recent characteristics and sources of halocarbons in eastern China remain unclear. Thus, hourly atmospheric observations of halocarbons were conducted in Hangzhou throughout 2021. The results showed that methylene chloride (CH2Cl2) was the most abundant halocarbon (2207 (25 %-75 % quantile: 1116-2848) ppt; parts per trillion) followed by chloromethane (CH3Cl) (912 (683-1043) ppt), and 1,2-dichloroethane (CH2ClCH2Cl) (596 (292-763) ppt). Then, backward trajectory and potential source contribution function (PSCF) analysis show that the emission hot spots of halocarbons were concentrated in adjacent cities in Zhejiang and neighboring provinces in eastern China. Moreover, based on positive matrix factorization (PMF) analysis, industrial emission (38.7 %), solvent usage (32.6 %), and the refrigeration sector and biomass burning (23.7 %) were the main sources of halocarbons (observed in this study). This study reveals high concentrations and potential sources of halocarbons in eastern China, which are important for studying the recovery of the ozone layer.

6.
J Environ Sci (China) ; 124: 723-734, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36182177

RESUMO

Understanding the emission sources of volatile organic compounds (VOCs) is critical for air pollution mitigation. Continuous measurements of atmospheric VOCs were conducted from January to February in Hangzhou in 2021. The average measured concentration of total VOCs (TVOCs) was 38.2 ± 20.9 ppb, > 42% lower than that reported by previous studies at the urban center in Hangzhou. The VOC concentrations and proportions were similar between weekdays and weekends. During the long holidays of the Spring Festival in China, the concentrations of TVOCs were ∼50% lower than those during the regular days, but their profiles showed no significant difference (p > 0.05). Further, we deduced that aromatics and alkenes were the most crucial chemicals promoting the formation of O3 and secondary organic aerosol (SOA) in Hangzhou. According to interspecies correlations, combustion processes and solvent use were inferred as major VOC emission sources. This study provides implications for air quality improvements before and during the upcoming Asian Games that will be hosted in Hangzhou in 2022.


Assuntos
Poluentes Atmosféricos , Ozônio , Compostos Orgânicos Voláteis , Aerossóis/análise , Poluentes Atmosféricos/análise , Alcenos/análise , China , Monitoramento Ambiental , Ozônio/análise , Solventes , Compostos Orgânicos Voláteis/análise
7.
Front Psychol ; 13: 1041644, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36438348

RESUMO

With the increasingly prominent role of social media in the timeliness and sharing of information dissemination, more and more research has focused on how to further improve user stickiness through social media. However, there is little consideration of the impact of celebrities' views on user behavior in social media. The main goal of this paper is to study the influence of celebrity language style on user communication and opinions dissemination. First, it analyzes the language style characteristics of celebrities' opinions and conducts cross-influence analysis between celebrity language style characteristics and user communication characteristics. Based on speech act theory, this study studies the influence of different language styles of celebrity Microblog on users' communication behavior and then builds a potential category analysis model to subdivide the views of celebrities. The results show that (1) Positive expression is the most common language style element combination of celebrities, and it also shows the most effective communication effect. This shows that users like to see celebrities show an active and positive side to the outside world, can analyze external things, and express their own opinions on these contents; (2) The combination of positive emotion, external attention, and analysis can produce the best communication effect; (3) The emotion of celebrities' opinions will affect the communication emotion of users to a certain extent, and the communication of users will have the development trend of reducing positive emotions and increasing negative emotions. Therefore, positive guidance and the dissemination of positive energy are more needed on public social platforms to minimize or avoid the dissemination of negative emotions.

8.
Environ Sci Process Impacts ; 24(11): 1968-1981, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36000414

RESUMO

Volatile organic compounds (VOCs) are important precursors of severe pollution of ozone (O3) and secondary organic aerosols in China. Fully understanding the VOCs emission is crucial for making regulations to improve air quality. This study reviews the published studies on atmospheric VOCs concentration observations in China and observation-based estimation of China's VOCs emission strengths and emission source structures. The results reveal that direct sampling and stainless-steel-tank sampling are the most commonly used methods for online and offline observations in China, respectively. The GC-MS/FID is the most commonly used VOCs measuring instrument in China (in 60.8% of the studies we summarized). Numerous studies conducted observation campaigns in urban areas (76.2%) than in suburban (17.1%), rural (18.1%), and background areas (14.3%) in China. Moreover, observation sites are largely set in eastern China (83.8%). Though there are published studies reporting observation-based China's VOCs emission investigation, these kinds of studies are still limited, and gaps are found between the results of top-down investigation and bottom-up inventories of VOCs emissions in China. In order to enhance the observation-based VOCs emission investigations in China, this study suggests future improvements including: (1) development of VOCs detection techniques, (2) strengthening of atmospheric VOCs observations, (3) improvement of the accuracy of observation-based VOCs emission estimations, and (4) facilitation of better VOCs emission inventories in China.


Assuntos
Poluentes Atmosféricos , Ozônio , Compostos Orgânicos Voláteis , Compostos Orgânicos Voláteis/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Ozônio/análise , China
9.
Environ Res ; 214(Pt 2): 113944, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35870498

RESUMO

China has shut down and abandoned a substantial number of coal mines since 1999, which have been releasing methane (CH4) for many years. However, the characteristics of China's abandoned mine methane (AMM) emissions are still unclear; this is a concerning knowledge gap because coal mines are the largest contributor to China's anthropogenic CH4 emissions. This study used two methods to estimate China's historical AMM emissions over the past 40 years (1980-2020) and to project its AMM emissions to 2060 which is the target year for China's carbon neutrality goal. The results show that China's AMM emissions increased substantially from 0.11 ± 0.03 million tons per year (Mt/yr) (3.1 ± 0.84 Mt/yr CO2-eq) in 1980 to 4.7 ± 0.94 Mt/yr (131 ± 26 Mt/yr CO2-eq) in 2020. An accelerated growth rate was found during 1998-2005, with AMM emissions rapidly increasing by approximately three times, which was consistent with the high number of mine shutdowns. In 2019, we found that AMM emissions had become the fourth largest anthropogenic source in China, higher than the national anthropogenic CH4 emissions of individual United Nations Framework Convention on Climate Change Annex I countries excluding the United States of America and the Russian Federation. If unabated, China's AMM emissions are projected to peak at 8.7 ± 2.6 Mt/yr in 2040 and reach approximately one-third of China's anthropogenic carbon dioxide emissions in 2060. This study reveals that understanding AMM emissions can help more accurately quantify China's total CH4 emissions and guide their future mitigation.


Assuntos
Dióxido de Carbono , Metano , Dióxido de Carbono/análise , Mudança Climática , Carvão Mineral , Metano/análise , Mineração , Estados Unidos
10.
Toxicon ; 212: 42-48, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35421437

RESUMO

Osteoarthritis (OA) is the most common cause to lead to chronic pain. Sensitization of pain pathways including central sensitization and peripheral sensitization has been regarded as a major cause of OA pain refractory to treatment. Addressing peripheral sensitization or central sensitization alone may not adequately treat OA pain. In our previous studies, botulinum toxin type A (BoNT/A) has been shown to reduce peripheral sensitization for analgesic effects. In addition, transcranial direct current stimulation (tDCS) has also been suggested to reduce central sensitization for analgesia. The present study was designed to investigate whether BoNT/A in combination with tDCS has better analgesic effects than isolated treatment to alleviate OA-induced chronic pain in rats. The Von Frey and hot plate tests were applied to assess the pain-related behaviors at different time points. The expression level of N-methyl-D-aspartate receptor-2B (NMDAR2B) was evaluated in midbrain periaqueductal gray (PAG) by Western blot the Immunohistochemistry staining after different treatments. The results showed that the combined treatment of BoNT/A and tDCS better improved the pain-related behaviors and significantly increased the expression level of NMDAR2B protein in PAG than each isolated treatment. These results suggested that the combined treatments for relief of chronic pain were more obvious than each isolated treatment. The combination of BoNT/A and tDCS may relieve pain by increasing N-methyl-D-aspartate (NMDA) receptors in the PAG, and then the descending inhibitory systems were activated to modulate peripheral and central sensitization.


Assuntos
Toxinas Botulínicas Tipo A , Dor Crônica , Osteoartrite , Estimulação Transcraniana por Corrente Contínua , Analgésicos , Animais , Toxinas Botulínicas Tipo A/uso terapêutico , Dor Crônica/tratamento farmacológico , Osteoartrite/tratamento farmacológico , Ratos , Estimulação Transcraniana por Corrente Contínua/métodos
11.
J Pain Res ; 15: 203-214, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35115824

RESUMO

PURPOSE: Osteoarthritis (OA) is the most common cause to lead to chronic pain. Transcranial direct current stimulation (tDCS) has been widely used to treat nerve disorders and chronic pain. The benefits of tDCS for chronic pain are apparent, but its analgesic mechanism is still unclear. This study observed the analgesic effects of tDCS on OA-induced chronic pain and the changes of NMDA receptor levels in PAG after tDCS treatment in rats to explore the analgesic mechanism of tDCS. METHODS: After establishing chronic pain by injecting monosodium iodoacetate (MIA) into the rat ankle joint, the rats received tDCS for 14 consecutive days (20 min/day). Before tDCS treatment, Ifenprodil (the selective antagonist of NMDAR2B) was given to rats in different ways: intracerebroventricular (i.c.v.) injection or intraperitoneal (i.p.) injection. The Von Frey and hot plate tests were applied to assess the pain-related behaviors at different time points. The expression level of NMDAR2B was evaluated in midbrain periaqueductal gray (PAG) by Western blot. In addition, NMDAR2B and c-Fos were observed by the Immunohistochemistry staining after tDCS treatment. RESULTS: The mechanical allodynia and thermal hyperalgesia were produced after MIA injection. However, tDCS treatment reverted the mechanical allodynia and thermal hyperalgesia. Moreover, tDCS treatment significantly increased the expression of NMDAR2B and the proportion of positive stained cells of NMDAR2B. Besides that, the tDCS treatment also decreased the proportion of positive stained cells of c-Fos in PAG. However, these changes did not occur in the rats given the Ifenprodil (i.c.v.). CONCLUSION: These results indicate that tDCS may increase the expression of NMDA receptors in PAG and strengthen the NMDA receptors-mediated antinociception to alleviate OA-induced chronic pain in rats.

12.
Toxicon ; 206: 55-63, 2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-34954133

RESUMO

Neuropathic pain in osteoarthritis is one of the reasons why the pain is difficult to treat, and P2X4R plays an important role in neuropathic pain. In addition, BoNT/A has been proven to have analgesic effects on both neuropathic pain and osteoarthritis, but its exact mechanism is still unknown. This study aims to investigate the relationship between the analgesic effect of BoNT/A on osteoarthritis and the expression of P2X4R in spinal cord microglia. The analgesic effect was compared between BoNT/A and compound betamethasone. Western blot analysis was used to examine the expression of P2X4R and BDNF proteins in the spinal cord. Immunohistochemistry was used to determine the cellular location of P2X4R. Mechanical allodynia and weight asymmetry were identified using the hind paw withdrawal threshold and weight bearing test. The results showed that intra-articular injection of MIA induced persistent mechanical allodynia and weight asymmetry in rats. Both BoNT/A and betamethasone could relieve pain behavior in rats, but BoNT/A had a more obvious effect and lasted longer. Furthermore, BoNT/A could reverse the MIA-induced overexpression of BDNF and P2X4R in the spinal dorsal horn. To sum up, BoNT/A is more effective than betamethasone in relieving MIA-induced osteoarthritis pain in rats, and its analgesic effect may be related to the regulation of P2X4R-mediated BDNF release in spinal microglia and the relief of neuropathic pain in osteoarthritis.


Assuntos
Neuralgia , Osteoartrite , Animais , Modelos Animais de Doenças , Hiperalgesia , Microglia , Neuralgia/tratamento farmacológico , Osteoartrite/tratamento farmacológico , Ratos , Ratos Sprague-Dawley , Medula Espinal
13.
Front Pharmacol ; 12: 735075, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34803684

RESUMO

Arthritis is the most common cause to lead to chronic pain. Botulinum toxin type A (BoNT/A) has been widely used to treat chronic pain. In our previous study, we confirmed the anti-inflammatory and antinociceptive effects of BoNT/A in the Complete Freund's Adjuvant (CFA)-induced arthritis model, but the underlying anti-inflammatory mechanism was not fully elucidated. The purpose of this study was to investigate the anti-inflammatory effects and mechanisms of BoNT/A on arthritis using transcriptomic analysis. The BoNT/A was injected into the rat ankle joint on day 21 after CFA injection. The von Frey and hot plate tests were applied to assess the pain-related behaviors at different time points. Five days after BoNT/A treatment, gene expression profiling in dorsal root ganglion (DRG) was performed using RNA sequencing (RNA-seq). The differentially expressed genes (DEGs) were analyzed by various tools. The mechanical allodynia and thermal hyperalgesia were significantly reversed after BoNT/A injection. RNA-seq revealed 97 DEGs between the CFA group and Sham group; these DEGs were enriched inflammatory response, IL-17 signaling pathway, etc. There are 71 DEGs between the CFA+BoNT/A group and the CFA group; these DEGs related to response to peptide, PI3K-Akt signaling pathway, ECM-receptor interactions, etc. Three key genes were significantly decreased after CFA-induced arthritis pain, while BoNT/A increased the expression of these genes. The identification of S100A9, S100A8, and MMP8 genes can provide new therapeutic targets for arthritis pain and affect the signaling pathway to play an anti-inflammatory role after the treatment of BoNT/A.

14.
Front Neurosci ; 15: 661663, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34163322

RESUMO

Intracerebral hemorrhage (ICH) is a dangerous neurological disease. The mechanism of ferroptosis in ICH remains unclear. Using bioinformatics analysis, we aimed to identify the key molecules involved in ferroptosis and provide treatment targets for ICH to further explore the mechanism of ferroptosis in ICH. GSE24265 was downloaded from the Gene Expression Omnibus (GEO) dataset and intersected with ferroptosis genes. A total of 45 differentially expressed genes (DEGs) were selected, most of which were involved in the TNF signaling pathway and oxidative stress response. Key modules constructed by the protein-protein interaction (PPI) network analysis and screening of genes related to the TNF signaling pathway led to the confirmation of the following genes of interest: MAPK1, MAPK8, TNFAIP3, ATF4, and SLC2A1. Moreover, MAPK1 was one of the key genes related to TNF signaling and oxidative stress, and it may play an important role in ferroptosis after cerebral hemorrhage. The MAPK1-related molecules included hsa-miR-15b-5P, hsa-miR-93-5P, miR-20b-5p, SNHG16, XIST, AC084219.4, RP11-379K17.11, CTC-444N24.11, GS1-358P8.4, CTB-89H12.4, RP4-773N10.5, and FGD5-AS1. We also generated a hemorrhage rat model, which was used to conduct exercise intervention in ICH rats, and qRT-PCR was used to assess the expression levels of our genes of interest. The mRNA levels after cerebral hemorrhage showed that MAPK1, ATF4, SLC2A1, and TNFAIP3 were upregulated, whereas MAPK8 was downregulated. Treadmill training increased the expression of anti-inflammatory molecules TNFAIP3 and SLC2A1 and reduced the expression of MAPK1, ATF4, and MAPK8, indicating that treadmill training may be utilized as antioxidant therapy to decrease neuronal ferroptosis. The results of this study indicated that the MAPK1-related mRNA-miRNA-lncRNA interaction chain could be potentially employed as a biomarker of the inception and progression of ferroptosis after cerebral hemorrhage.

15.
Environ Int ; 156: 106710, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34144364

RESUMO

Accurate measurement and estimation on the trends and spatial distributions of VOCs emissions in China are critical to establishing efficient local or regional pollution control measures, while less is known about the discrepancies on VOCs emissions estimated by previous studies. In this study, two of the estimation approaches including the bottom-up and top-down methods have been reviewed with the data collected from many studies. The approaches demonstrated that the total anthropogenic VOCs emissions in China have been increasing since 1949. The contributions of industrial and solvent use to total VOCs emissions have been increasing since 2000, whereas the contributions of transportation sector have shown a decreasing trend since 2000. The contributions of fuel combustion have also been decreasing since 1950. The gaps of emission estimates for the industry and solvent use were 99.3 ± 22.7% and 81.5 ± 41.8%, respectively, which distributed in much wider ranges than other sources (e.g. 28.9 ± 16.7% for fuel combustion). In comparison to the top-down method, larger variations on the annual VOCs emission estimates were seen using the bottom-up method that comprised different data sources. For the view of spatial pattern, most hot emission estimate spots were concentrated in the eastern China, consistent to their relatively stronger strengths in the industrialization and urbanization. Although the total VOCs emission in China has been continuously increasing during 2008-2016, the VOCs emissions per gross domestic production (GDP) showed a decreasing trend. As for individual compounds, large discrepancy was seen on formaldehyde, with the coefficient of variation (CV) ranged from 37% to 128% over the years. In overall of view, the importance of industrial process and solvent use is increasing. More focuses must be made to these two sources. Emissions of individual compound, particularly those of oxygenated VOCs, were not completely determined and should be better quantified.


Assuntos
Poluentes Atmosféricos , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , China , Monitoramento Ambiental , Urbanização , Compostos Orgânicos Voláteis/análise
16.
Infect Dis Poverty ; 10(1): 57, 2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33902684

RESUMO

BACKGROUND: Mosquito-based arbovirus surveillance can serve as an early warning in evaluating the status of mosquito-borne virus prevalence and thus prevent local outbreaks. Although Tengchong County in Yunnan Province-which borders Myanmar-is abundant and diverse in mosquitoes, very few mosquito-based arbovirus investigations have been conducted in the recent decade. Herein, this study aims to evaluate the presence and the diffusion of mosquito-borne pathogens, currently prevalent in this region. METHODS: We collected 9486 mosquitoes, representing eight species, with Culex tritaeniorhynchus and Anopheles sinensis as the dominant species, during high mosquito activity seasons (July-October) in Tengchong, in 2018. Samples collected from 342 pools were tested using reverse-transcription PCR to determine the species, distribution, and infection rates of virus and parasite, and further analyze their genotypes, phylogenetic relationships, infection rate, and potential pathogenicity. RESULTS: Fifteen Japanese encephalitis virus (JEV) strains from Cx. tritaeniorhynchus pools were detected. Seven strains of insect-specific flaviviruses (ISFVs), including two Aedes flavivirus (AeFV) and Yunnan Culex flavivirus strains each, one Culex theileri flavivirus, Yamadai flavivirus (YDFV) and Anopheles-associated flavivirus (AAFV) strains each were detected in Aedes albopictus, Cx. tritaeniorhynchus, Cx. vagans, Cx. pseudovihnui, and An. sinensis pools, respectively. The whole-genome was successfully amplified in one strain of JEV and AeFV each. Phylogenetic analysis using the E gene placed all the newly detected JEV strains into the GI-b genotype. They showed highly nucleotide identities, and were most closely related to the strain detected in Tengchong in 2010. The comparison of the E protein of JEV strains and vaccine-derived strain, showed six amino residue differences. The bias-corrected maximum likelihood estimation values (and 95% confidence interval) for JEV in Cx. tritaeniorhynchus collected in Tengchong in 2018 were 2.4 (1.4-3.9). CONCLUSIONS: A potential Japanese encephalitis epidemic focus with the abundance of host mosquitoes and high JEV infection rate was observed in Tengchong. In addition, at least five species of ISFVs co-circulate in this area. This study highlights the importance of widespread and sustained mosquito-based arbovirus surveillance in local areas to prevent the transmission of JEV, and other emerging/re-emerging mosquito-borne pathogens.


Assuntos
Anopheles , Encefalite Japonesa , Epidemias , Flavivirus , Vírus , Animais , China/epidemiologia , Encefalite Japonesa/epidemiologia , Flavivirus/genética , Epidemiologia Molecular , Mianmar/epidemiologia , Filogenia
17.
Sci Prog ; 103(1): 36850419877727, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31829883

RESUMO

In order to perceive the state of the process of reverse thinning spinning of the ultra-thin wall tube, a monitoring method based on drum shape is proposed. The method uses the non-uniform rational basis spline curve fitting method based on the moving least squares method to reconstruct the outer contour data of the spinning zone collected by the line laser displacement sensor and extracts the outer contour curve of the drum zone according to the spinning characteristics. Then, the dynamic time warping algorithm is used to analyze the similarity between the current and previous drum curves in order to judge whether the current spinning state is abrupt or not. At the same time, the current spinning state is judged by combining the curvature comb of the drum curve, the number of convex areas of the drum curve, the drum ratio, and the drum change trend. Finally, the drum shape detection and the spinning condition monitoring experiments are carried out. The experimental results show that this method can obtain the outer contour shape of the drum section at one time, and the accuracy is 0.05 mm with respect to the measured value of the three coordinates. The method can realize the visual monitoring of the abrupt change of the spinning process by judging the similarity of the drum curve at the adjacent time under different spinning states. In the state of instability, the curvature comb of the drum curve is discontinuous, the curve is G0 continuous, the drum ratio exceeds the critical drum ratio 2.0, and there is more than one convex region, which realizes the monitoring of spinning state more accurately. The experimental results verify the correctness of the proposed method and prove that the method can be used as a new method to judge the stability of the ultra-thin-walled cylinder spinning process.

18.
RSC Adv ; 9(26): 14701-14707, 2019 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35516310

RESUMO

Herein, cationic latex particles (CL) of different particle sizes were introduced as a cross-linking center to enhance the mechanical properties of the hydrophobically-associated hydrogels (P(AAm-co-HMA)-CL). Firstly, cationic polymethylmethacrylate (PMMA) latex particles were synthesized via soap-free emulsion polymerization. Subsequently, P(AAm-co-HMA)-CL hydrogels with outstanding mechanical properties were prepared using acrylamide as the monomer, hexadecyl methacrylate as the hydrophobic molecule, and CL as the cross-linking center. The size of CL had a significant effect on the mechanical properties and self-recovery properties of the P(AAm-co-HMA)-CL hydrogels. The hydrogel with larger CL size exhibited low mechanical properties due to weak hydrophobic interactions. In contrast, the hydrogel with small CL size displayed excellent mechanical properties due to an effective entanglement of the hydrophobic chains with the smaller size CL, which significantly affects the mechanical properties of the hydrogel. As a result, the maximum fracture stress and fracture strain of the hydrogel were up to 1.47 MPa and 2847%, respectively. This study can have a profound impact on the development of the technology of toughening hydrogels with latex particles.

19.
Biomed Res Int ; 2016: 6875731, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27965979

RESUMO

Establishing an animal model of abdominal aortic aneurysm (AAA) is the key to study the pathogenesis and the pathophysiological features of AAAs. We investigated the effects of low-pressurized perfusion with different concentrations of elastase on aneurysm formation rate in the AAA model. Fifty male New Zealand white rabbits were randomly divided into A, B, C, D, and E groups. 10 µL of normal saline was perfused into the abdominal aorta in group A and 1 U/mL, 10 U/mL, 100 U/mL, or 200 U/mL of elastase was, respectively, perfused for the other four groups. All the animals were perfused for 7 min. Doppler ultrasound examinations of the abdominal aorta were performed before surgery and on day 14 after surgery. The rabbits were sacrificed and the perfused segment of the abdominal aorta was observed visually and after staining. The aneurysm formation rate of group A, group B, group C, group D, and group E was, respectively, 0%, 0%, 33.3%, 102.5-146.8%, and 241.5-255.2%. The survival rate of five groups was 90%, 90%, 90%, 90%, and 40%, respectively. So, we concluded that low-pressurized perfusion with 100 U/mL of elastase can effectively establish AAAs in rabbits with a high aneurysm formation rate.


Assuntos
Aorta Abdominal/efeitos dos fármacos , Aorta Abdominal/patologia , Aneurisma da Aorta Abdominal/patologia , Modelos Animais de Doenças , Elastase Pancreática/administração & dosagem , Reperfusão/métodos , Animais , Progressão da Doença , Relação Dose-Resposta a Droga , Humanos , Masculino , Coelhos
20.
PLoS One ; 11(3): e0151259, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27032086

RESUMO

OBJECTIVE: In the era of bare metal stents (BMSs), alloys have been considered to be better materials for stent design than stainless steel. In the era of biodegradable polymer drug-eluting stents (BP-DESs), the safety and efficacy of BP-DESs with different metal platforms (stainless steel or alloys) have not yet been reported, although their polymers are eventually absorbed, and only the metal platforms remain in the body. This study sought to determine the clinical safety and efficacy of BP-DESs with different platforms compared with other stents (other DESs and BMSs). METHODS: PubMed, Embase and Clinical Trials.gov were searched for randomized controlled trials (RCTs) that compared BP-DESs with other stents. After performing pooled analysis of BP-DESs and other stents, we performed a subgroup analysis using two classification methods: stent platform and follow-up time. The study characteristics, patient characteristics and clinical outcomes were abstracted. RESULTS: Forty RCTs (49 studies) comprising 34,850 patients were included. Biodegradable polymer stainless drug-eluting stents (BP-stainless DESs) were superior to the other stents [mainly stainless drug-eluting stents (DESs)] in terms of pooled definite/probable stent thrombosis (ST) (OR [95% CI] = 0.76[0.61-0.95], p = 0.02), long-term definite/probable ST (OR [95% CI] = 0.73[0.57-0.94], p = 0.01), very late definite/probable ST (OR [95% CI] = 0.56[0.33-0.93], p = 0.03) and long-term definite ST. BP-stainless DESs had lower rates of pooled, mid-term and long-term target vessel revascularization (TVR) and target lesion revascularization (TLR) than the other stainless DESs and BMSs. Furthermore, BP-stainless DESs were associated with lower rates of long-term death than other stainless DESs and lower rates of mid-term myocardial infarction than BMSs. However, only the mid-term and long-term TVR rates were superior in BP-alloy DESs compared with the other stents. CONCLUSION: Our results indirectly suggest that BP-stainless DESs may offer more benefits than BP-alloy DESs in the era of BP-DESs. Further well-designed RCTs comparing BP-stainless with BP-alloy DESs are needed to confirm which platform is better.


Assuntos
Materiais Biocompatíveis/metabolismo , Stents Farmacológicos , Polímeros/metabolismo , Ligas/química , Ligas/uso terapêutico , Materiais Biocompatíveis/química , Materiais Biocompatíveis/uso terapêutico , Ensaios Clínicos como Assunto , Bases de Dados Factuais , Humanos , Razão de Chances , Polímeros/química , Polímeros/uso terapêutico
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