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1.
Plant Sci ; 338: 111915, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37944702

RESUMO

Plant filamentation temperature-sensitive H (FtsH) proteins are ATP-dependent zinc proteases that play an important role in regulating abiotic stress adaptions. Here we explore their potential role in abiotic stress tolerance in alfalfa, an important legume crop. Genomic analysis revealed seventeen MsFtsH genes in five clusters, which generally featured conserved domains and gene structures. Furthermore, the expression of MsFtsHs was found to be tightly associated with abiotic stresses, including osmotic, salt and oxidative stress. In addition, numerous stress responsive cis-elements, including those related to ABA, auxin, and salicylic acid, were identified in their promoter regions. Moreover, MsFtsH8 overexpression was shown to confer tolerance to salt and oxidative stress which was associated with reduced levels of reactive oxygen species, and enhanced expression and activity of antioxidant enzymes. Our results highlight MsFtsHs as key factors in abiotic stress tolerance, and show their potential usefulness for breeding alfalfa and other crops with improved yield and stress tolerance.


Assuntos
Medicago sativa , Peptídeo Hidrolases , Medicago sativa/metabolismo , Temperatura , Peptídeo Hidrolases/metabolismo , Plantas Geneticamente Modificadas/genética , Tolerância ao Sal/genética , Melhoramento Vegetal , Estresse Oxidativo , Cloreto de Sódio/metabolismo , Estresse Fisiológico/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas
2.
Mol Biol Rep ; 50(12): 10097-10109, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37910387

RESUMO

BACKGROUND: Filamentation temperature-sensitive H (FtsH) is an AAA+ ATP-dependent protease that plays a vital role in plant environmental adaption and tolerance. However, little is known about the function of the FtsH gene family in the most important legume model plant, Medicago truncatula. METHODS AND RESULTS: To identify and investigate the potential stress adaptation roles of FtsH gene family in M. truncatula, we conducted a series of genome-wide characterization and expression analyses. Totally, twenty MtFtsH genes were identified, which were unevenly distributed across eight chromosomes and classified into six evolution groups based on their phylogenetic relationships, with each group containing similar structures and motifs. Furthermore, MtFtsH genes exhibited a high degree of collinearity and homology with leguminous plants such as alfalfa and soybean. Multiple cis-elements in the upstream region of MtFtsH genes were also identified that responded to light, abiotic stress, and phytohormones. Public RNA-seq data indicated that MtFtsH genes were induced under both salt and drought stresses, and our transcript expression analysis showed that MtFtsH genes of MtFtsH1, MtFtsH2, MtFtsH4, MtFtsH9, and MtFtsH10 were up-regulated after ABA, H2O2, PEG, and NaCl treatments. These results suggest that MtFtsH genes may play a critical role in drought and high salt stress responses and the adaption processes of plants. CONCLUSIONS: This study provides a systematic analysis of FtsH gene family in M. truncatula, serving as a valuable molecular theoretical basis for future functional investigations. Our findings also extend the pool of potential candidate genes for the genetic improvement of abiotic stress tolerance in legume crops.


Assuntos
Medicago truncatula , Medicago truncatula/genética , Medicago truncatula/metabolismo , Temperatura , Filogenia , Peróxido de Hidrogênio/metabolismo , Estresse Fisiológico/genética , Regulação da Expressão Gênica de Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
3.
J Environ Manage ; 345: 118564, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37421724

RESUMO

Rapid urbanization has led to a significant increase in water consumption and wastewater discharge. Balancing the relationship between urbanization development and water pollutants emissions is crucial for the sustainable development of the country. Given the uneven regional economic development and resource distribution in China, exploring the relationship between new urbanization and water pollution emissions cannot be limited to a single perspective such as population urbanization. This study developed a comprehensive evaluation index system for new urbanization level. Based on data from 30 provincial-level regions in China from 2006 to 2020, a Panel Threshold Regression Model (PTRM) was used to explore the nonlinear relationship between the new urbanization level and water pollution discharge. The research results show that China's new urbanization level (NUBL) and its subsystems, including population urbanization (P-NUBL), economic urbanization (E-NUBL), and spatial urbanization (SP-NUBL), all have a double threshold effect on chemical oxygen demand (COD) emissions. The promoting effect of NUBL and E-NUBL on COD emissions gradually increased in the later stage of the study. P-NUBL and SP-NUBL show a trend of inhibiting COD emissions after crossing the dual threshold values. Social urbanization (S-NUBL) and ecological urbanization (EL-NUBL) had no threshold effect, but they also had a promoting effect on COD emissions. In addition, the speed of new urbanization in eastern China was significantly faster than that in central and western China, with provinces such as Beijing, Shanghai, and Jiangsu being the first to enter the high threshold stage. The central region began to gradually enter the middle threshold stage, but provinces such as Hebei, Henan, and Anhui are still in the high pollution and high emission stage. The level of new urbanization in western China is relatively low, and future development should prioritize economic construction. Provinces with high thresholds and low water pollution emissions still need to be developed. The results of this study have important implications for promoting the harmonious development of water-saving and sustainable urban development in China.


Assuntos
Urbanização , Poluentes da Água , China , Poluição da Água , Desenvolvimento Econômico
4.
Parkinsonism Relat Disord ; 113: 105484, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37454429

RESUMO

BACKGROUND: Genetic susceptibility plays a significant role in Parkinson's disease (PD) development. Carriers of the Parkin S/N167 mutation may have an increased risk of PD and altered spontaneous brain activity. OBJECTIVE: This study aims to investigate the potential pathogenesis of PD through a comparative analysis of the amplitude of low-frequency fluctuations (ALFF) in resting-state functional magnetic resonance imaging (rs-fMRI) of subjects with Parkin gene S/N 167 polymorphisms, and to examine the association between spontaneous brain activity and clinical scale scores of PD. METHODS: A total of 69 PD patients and 84 healthy controls (HC) were included in the study. Each subject was genotyped for the Parkin gene S/N 167 polymorphism and underwent rs-fMRI scans. ALFF analysis was employed to evaluate the relationship among genotypes, interactive brain regions, and clinical symptoms in PD. RESULTS: PD patients exhibited decreased ALFF values in the right anterior lobe and vermis of the cerebellum compared to HC. No significant interaction was found between the gene's main effect and the "group × genotype" effect on brain ALFF values. One-factor ANOVA revealed no significant difference in ALFF values between PD subgroups; however, the ALFF values in the right anterior lobe and vermis of the cerebellum were lower in the PD-G and PD-GA groups compared to the HC-G and HC-GA groups. Spearman correlation analysis demonstrated that ALFF values in the PD-GG and PD-GA groups were negatively associated with UPDRS-III scores in the bilateral lingual gyrus (Lingual R/L). CONCLUSION: Parkin gene S/N 167 polymorphisms may influence brain functional activity in specific brain regions, and ALFF values are associated with motor symptoms in PD patients.


Assuntos
Doença de Parkinson , Humanos , Encéfalo/patologia , Mapeamento Encefálico , Cerebelo , Imageamento por Ressonância Magnética/métodos , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/genética , Doença de Parkinson/patologia , Polimorfismo Genético/genética
5.
J Environ Manage ; 344: 118353, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37354596

RESUMO

The essence of efficiency measurement is to model and estimate the performance of a complex system in a comparable form, and the key to modeling is to make the model as close to reality as possible. Based on data envelopment analysis (DEA) methods, this research proposes a layer-by-layer investigation framework for the black box. To illustrate the rationality of this logical framework, this paper presents a triple-opened dynamic recycling model with a series-parallel structure that allows us to assess the efficiency of the industrial water-related system in China. We obtain and compare the system efficiency under different scenarios for opening the black box. The results show that: (1) China's efforts to improve the performance of the resource use sub-stage through industrial production technology and management have been effective. (2) The performance of China's industrial water-related system strongly relates to the water supply subunit with a positive linear correlation. (3) The water supply subunit is the main foot-dragger in the system, and the government needs to place particular attention on improving the performance of labor in this subunit.


Assuntos
Indústrias , Água , China , Abastecimento de Água , Eficiência , Desenvolvimento Econômico
6.
Artigo em Inglês | MEDLINE | ID: mdl-36674265

RESUMO

The initial emission rights allocation is the key measure to achieve the goal of total amount control and deepen the emission trading system. Although many studies have focused on the modeling of initial emission rights allocation, such as using game theory and multi-objective optimization methods, few studies have observed the hierarchical relationship of mutual interference and restriction between watershed management agency and local governments in each subarea during allocation. This relationship directly affects the rationality of the results of regional emission rights allocation. In this study, a leader-follower hierarchical decision model (LFHDM) for allocating initial emission rights in a basin is developed. Based on the bilevel programming approach, the model simulates the interactive decision-making process between the watershed management agency of the upper-level model (LFHDM-U) and the local government of the lower-level model (LFHDM-L) in the allocation under total amount control. A case study of China's Yellow River Basin is conducted to demonstrate the feasibility and practicality of the model. Findings reveal that, compared with the single-level model, the developed LFHDM has higher satisfaction with the allocation scheme. Under different scenarios, the overall satisfaction of the configuration schemes of COD and NH3-N in each province and autonomous region remains above 0.9. In addition, the allocation volumes of COD and NH3-N in each province of the Yellow River Basin in planning year increase with the enhancement of allowable assimilative capacity of water bodies, but the interval gap of satisfaction with allocation schemes gradually narrows. It shows that when the allowable assimilation capacity of a water body is low, the decision-making of the allocation scheme needs to be more cautious. Moreover, for the Yellow River Basin, apart from Qinghai and Sichuan, the task of reducing water pollutants in other provinces in the next few years is very arduous. The average reduction of total COD and NH3-N in the basin is about 48% and 46%, respectively.


Assuntos
Poluentes da Água , Teoria dos Jogos , Rios , Água , China
7.
Environ Sci Pollut Res Int ; 30(14): 40298-40314, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36609756

RESUMO

As a critical way to realize the optimal allocation of water environment capacity resources in the basin, emission rights trading faces multiple uncertainties, making it extremely hard and challenging to formulate appropriate decisions and plans. Therefore, this study uses interval two-stage stochastic programming (ITSP) method to model the emission rights trading process with multiple uncertainties. It can promote the secondary optimal allocation of the emission rights between the demander and the supplier after the initial allocation. Externalities caused by environmental problems are internalized through the form of emission rights trading, thereby reducing the transaction costs and promoting the coordination and integrity of water pollution control among governments in a basin. Finally, the Yellow River basin is taken as an example for case analysis. The results show that the net revenue of emission rights system in the transaction status is better than that in the non-transaction status, and the average gap of net income reaches [171.031, 193.056] billion yuan. Under different reduction policies, the average water pollutant emission reduction in transaction status is [451.15, 628.34] thousand tons, which is generally less than [516.57, 670.05] thousand tons in non-transaction status. As policies get stricter and assimilative capacity of water bodies dwindles, reduction shrinks, leading to higher risks and economic loss from being unable to meet the discharge demand. When reduction policies are relatively loose and assimilative capacity is high, emission rights trading volume peaks. At this time, the trading volume of COD reached [29.05, 40.76] thousand tons, and that of NH3-N reached [3.74, 4.31] thousand tons. All these findings will offer insights for decision-makers on how to strike a balance between economic benefits and emission rights trading plans in the Yellow River basin.


Assuntos
Rios , Poluentes da Água , Incerteza , Modelos Teóricos , Água , China
8.
Environ Sci Pollut Res Int ; 30(8): 22000-22012, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36282377

RESUMO

Water rights trading is an effective way to promote the redistribution of agricultural water saving within and among water-shortage regions. Reasonable transfer price can not only improve the income of farmers and irrigation areas, but also improve the efficiency of agricultural water use. However, the trading across industries or regions will diminish the ecosystem service value of arable land, and negatively impacts irrigation areas. This paper investigates the pricing model of agricultural water transaction, which combines water trading with ecological compensation to balance the benefits of both parties. A bi-level programming model of agricultural water trading was established for optimizing the prices and corresponding volumes of transaction across users in water markets. The context of this study is the Inner Mongolia Autonomous Region, which is a typical water-shortage region in China. Results show that adjusting price variables through the model, including transaction price and ecological compensation, led to an optimization of transaction volumes across users. The economic benefits also are optimized between the irrigation districts and industrial water users. Pricing model of water trading is also improved with ecological compensation. This study ultimately provides a useful reference for policy-makers in water-shortage regions.


Assuntos
Ecossistema , Água , China , Agricultura , Custos e Análise de Custo
9.
Prev Sci ; 24(1): 50-63, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35939179

RESUMO

Early tobacco smoke exposure (TSE) in utero and/or during the first years after birth poses threats to the development of child executive functioning and self-regulation skills, including inhibitory control. Efforts are still needed to examine under what conditions such effects may occur and thus identify modifiable intervention targets. In addition, a distinction between cool and hot inhibitory control is also important to obtain greater nuance in such links. The cool inhibitory control refers to children's suppression of prepotent automatic responses to a distracting stimulus in solving arbitrary and decontextualized problems, whereas the hot inhibitory control refers to children's control of impulse in motivationally and emotionally high-stake situations. Using data derived from the National Institute of Child Health and Human Development Study of Early Child Care and Youth Development, we examined the links between early risk of TSE and preschoolers' hot and cool inhibitory control and tested the potential promotive/protective roles of maternal positivity in early mother-child interactions. Results indicate that early risk of TSE was negatively linked to child cool inhibitory control when maternal positivity was low, but this link was nonsignificant when maternal positivity was high (i.e., the protective role of maternal positivity). The link between early risk of TSE and child later hot inhibitory control was not moderated by maternal positivity; instead, early risk of TSE and maternal positivity were negatively and positively associated with child hot inhibitory control above and beyond each other, respectively (i.e., the promotive role of maternal positivity). Accordingly, building a tobacco-free environment during pregnancy and infancy likely yields long-term benefits for child self-regulation development. Improving early mothering may offset the negative link between early TSE and child cool inhibitory control and also facilitate child hot inhibitory control even in the face of early TSE.


Assuntos
Poluição por Fumaça de Tabaco , Feminino , Gravidez , Adolescente , Humanos , Mães , Função Executiva , Desenvolvimento Infantil , Relações Mãe-Filho
10.
Health Commun ; 38(1): 71-79, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34082619

RESUMO

Patient engagement is now widely endorsed as an essential ingredient for high-quality healthcare, yet there has been limited research on how patient engagement can be facilitated in medical informed consent (IC) communication. To address this gap, a fine-grained discourse analysis was conducted to identify communication strategies adopted by doctors to facilitate information delivery and ascertain patients' understanding, which translate into an increase in patient engagement. Data was collected from a public hospital in mainland China. Nonparticipating observations of 14 IC sessions were audio-recorded, followed by in-depth, semi-structured interviews with those observed patients. Four communication strategies emerged from the analysis: 1) seeking patients' understanding of their condition; 2) explaining medical information by reference to shared knowledge and practice; 3) recognizing and addressing patients' psychological concerns; 4) repeating critical information and checking patients' understanding through teach-back. The adoption of these strategies enables doctors to tailor the scope and delivery of information to accommodate and address patients' preferences, rather than defaulting to one-way information dumping. This study sheds light on the complexity of IC and further contributes to the ongoing endeavors to improve IC communication by raising the awareness of the role of patients in making mutually acceptable decisions. These identified strategies can be incorporated into medical communication training to facilitate delivery of healthcare that is sensitive to patients' needs and expectations.


Assuntos
Participação do Paciente , Médicos , Humanos , População do Leste Asiático , Consentimento Livre e Esclarecido , Comunicação , Pesquisa Qualitativa , Relações Médico-Paciente
11.
Front Psychol ; 13: 943840, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36578682

RESUMO

This study aims to explore the nature of GP-counsellor interaction during discussions of patients' mental health issues in primary care services. An ethnographic discourse analysis of audio-recorded GP-counsellor conversations and the participating counsellor's reflective accounts. Two participating GPs and one counsellor were recruited from a private medical clinic in Hong Kong. The GPs and the counsellor mainly discussed their patients' issues in terms of medication management, the counsellor's case conceptualization, the case management, knowledge transfer and acknowledging the partnership. During case discussions, both the GPs and the counsellor used a range of interactional strategies to clarify a patient's condition and treatment plans for mutual understanding. The GPs and the counsellor co-construct an insider discourse that covers a greater diversity of topics, including both medical and non-medical concerns. The research findings have implications for theory and practice, including the potential of ethnographic discourse analysis in understanding the features of participants' behavior and evaluating the effectiveness of communication in a particular setting, as well as the importance of exploring professionalized discourse during GP-counsellor communication in developing training programs aimed at enhancing staff awareness of effective IPC communication.

12.
Front Med (Lausanne) ; 9: 945011, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35911416

RESUMO

Objective: The relationship between gender and short-term prognosis of patients with anti-neutrophil cytoplasmic antibody (ANCA) associated vasculitis (AAV) is unclear, hence single-center retrospective analysis and meta-analysis were conducted to determine the relationship. Methods: Initially treated patients with AAV were retrospectively enrolled. Data of clinical manifestation, laboratory indicators, Birmingham vasculitis activity score (BVAS), therapeutic treatments, and the patients' situations within 1 year were recorded. First, we compared the basic characteristics between male and female patients. Second, the risk factors associated with a 1-year mortality rate of patients with AAV were evaluated. Finally, a meta-analysis was performed to explore the effect of gender on 1-year mortality in patients with AAV. Results: The study involved 84 patients with AAV, including 33 female and 51 male participants. In total, 14 people died (12 males and 2 females) and 70 survived in the 1st year. Statistical differences were noted in the age of onset, the course of the disease, WBC, HB, N, ESR, CRP, BUN, ALT and ALB, BVAS, and 1-year mortality rate between male and female participants. In male patients, elevated Scr, NLR, PLT, and RDW-CV were associated with poor AAV (P < 0.05) prognosis. The meta-analysis verified that male gender was an independent risk factor for the 1-year mortality of patients with AAV(OR = 1.54). Conclusion: Significant sex-specific differences were found in patients with AAV. Male patients contributed to 1.54-fold of 1-year mortality risk in patients with AAV by meta-analysis. More attention should be paid to the mortality risk of male patients with AAV in the early stage.

13.
Sci Total Environ ; 851(Pt 1): 158084, 2022 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-35981596

RESUMO

Countries are now struggling to improve their recycling efficiency of an industrial operational system to achieve the Sustainable Development Goals, yet scant studies have viewed the series-parallel recycling structure of the system based on data envelopment analysis (DEA). This research divides the system into industrial production and industrial waste treatment (IWT) processes connected serially, while the IWT process is further separated into treatment sub-units for wastewater, waste gas, and solid wastes connected in parallel. We propose a dynamic series-parallel recycling DEA model within a directional distance function to measure efficiency and discuss the efficiency relationship among the system, processes, and sub-units. By using the spatial Durbin model, we explore factors that mainly influence the efficiency for the 30 provinces during 2011-2019. The results show the following. (1) The medium performance of the industrial operational system with an average overall recycling efficiency of 0.69 is mainly caused by the poor performance of the IWT process with a score of 0.61. (2) The highest performance is observed in the wastewater treatment sub-unit, followed by waste gas treatment and solid waste treatment sub-units. (3) Market-based environmental regulations significantly promote local IWT efficiency, while command-and-control environmental regulations have no significant effect on local IWT efficiency. But they all have significant spatial spillovers. The voluntary environmental regulations have no significant impact.


Assuntos
Resíduos Industriais , Resíduos Sólidos , China , Eficiência , Indústrias , Reciclagem , Águas Residuárias
14.
Artigo em Inglês | MEDLINE | ID: mdl-35897300

RESUMO

Water stress in countries within a drainage basin exacerbates the water quantity conflict in transboundary rivers. However, few studies considered the invisible effect of virtual water transfer on water quantity conflict by intensifying water stress. Therefore, this study, with Ili River as the case, collects data on Virtual Water Trade (VWT) from 1990 to 2015, uses water stress index (WSI) to assess water stress values under two scenarios (with or without virtual water transfer), and takes Grey Verhulst Model to predict two scenarios water stress values respectively. Next, based on the Levenberg-Marquardt (LM) Algorithm, this study compares the water quantity conflict intensity of the two scenarios, and further explores the invisible effect of virtual water transfer on the conflicts among transboundary rivers. Results show: (1) During the study period (1990-2015), water stress in China and Kazakhstan along the banks of Ili River increased in general. (2) China was basically a net exporter of virtual water during 1990-1995, and Kazakhstan became a net exporter after 1995. (3) During 2020-2025, water conflict value of Ili River without virtual water transfer is 0.458, while the value rises to 0.622 with virtual water transfer, indicating that virtual water transfer between China and Kazakhstan has an invisible enhancement on the water quantity conflict of Ili River. (4) The intensified water quantity conflict is mainly caused by the more and more serious water stress in Kazakhstan. On such basis, it is more urgent for Kazakhstan to restructure its economy and trade.


Assuntos
Desidratação , Rios , China , Humanos , Cazaquistão , Rios/química
15.
Front Psychol ; 13: 910603, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35719577

RESUMO

This study investigates the strategies for learning Cantonese that are adopted by non-Chinese English-speaking ethnic minority (EM) university students in Hong Kong. The aim is to identify the challenges these students face in applying their strategies to learn Cantonese and to explore their learning experiences when implementing them. Drawing on questionnaire surveys and semi-structured interviews with 30 EM students at a university in Hong Kong, this study identifies these learners' strategies, elicits their views on the use of these strategies and examines their learning experiences. The findings suggest that EM students are "medium strategy users," with social strategies being their most commonly used types of learning strategies, followed by compensation and metacognitive strategies. The more proficient Cantonese users tend to use metacognitive strategies that promote planning and are goal-oriented. Taken together, this study sheds light on the complex interplay of sociocultural variables in shaping EM university students' Cantonese learning experience in Hong Kong. It also highlights the importance of analysing EM students' linguistic repertoire and the local language ecology in understanding Cantonese learning in a multilingual context like Hong Kong.

16.
Sci Total Environ ; 803: 150135, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34525728

RESUMO

Carbonation treatment (CT) by alkaline fly ash (FA) affects the stability of potentially toxic elements (PTEs). This study investigated the leachability and environmental risk of six PTEs contained in FA during natural and accelerated carbonation (NC, AC) using two typical leaching scenarios with distilled water (DW) and acetic acid (AA). The leaching of Pb/Cu/Cr/Ni in solidified/stabilized FA decreased due to CT in DW leaching, but the leaching of Pb/Zn/Cu/Cd increased due to CT in AA leaching. The leaching of the six PTEs (especially Pb/Cd) in AA leaching was significantly higher than that in DW leaching. CT was a promoting factor to increase the environmental risk level of PTEs in FA leachate, especially in AA leaching with H+ input. In the early stage of NC, under DW leaching tests, the environmental risk level of PTEs in FA leachate can be weakened due to the formation of carbonate minerals in the FA matrix. However, excessive NC increases the environmental risk of leached PTEs due to the decalcification of carbonate minerals. Both NC and AC increased the potential environmental risk of PTEs contained in the carbonated FA matrix. The nucleation and dissolution of carbonate minerals were interdependent with the immobilization and leaching of PTEs, which played a dominant role in the CT and leaching tests respectively. They jointly affected the occurrence behavior of PTEs in the FA matrix in CT tests and the leachability of PTEs in leaching tests. This study demonstrates that it is more scientific to evaluate the leachability of PTEs in carbonated FA according to the actual disposal scenarios.


Assuntos
Metais Pesados , Eliminação de Resíduos , Carbono , Carbonatos , Cinza de Carvão , Incineração , Metais Pesados/análise , Material Particulado , Resíduos Sólidos/análise
17.
Int J Pharm ; 607: 120975, 2021 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-34363913

RESUMO

Surgery combined with postoperative treatment is a widely accepted therapeutic strategy against breast cancer. Macrophage-based carriers have been proved to be an effective postoperative drug delivery system due to their inflammatory tendency. However, the slow and incomplete release of the cargo and the postoperative inflammation remain to be solved. Here, we described a macrophage-mediated photothermal therapy combined with anti-inflammatory strategy to inhibit breast cancer postoperative relapse. The anti-inflammatory resveratrol and photothermal agent indocyanine green (ICG) were loaded in octaarginine (R8)-modified liposomes, then ingested by macrophages to form the macrophage-based drug delivery system (Res/ICG-R8-Lip@MP). Res/ICG-R8-Lip@MP showed effective tumor-targeting ability via inflammatory tropism of macrophages and excellent near-infrared (NIR) photothermal performance. In vitro experiments showed that the carrier could not only trigger drug release though inflammation, but also utilize the photothermal conversion property to destroy the macrophage-based carrier at the local tumor to maximize drug release. In vivo experiments indicated that Res/ICG-R8-Lip@MP ablated residual tumor tissues and reduced the postoperative inflammation, and at the same time achieved significant effect of inhibiting tumor postoperative relapse. This synergistic photothermal and anti-inflammatory strategy has great potential in postoperative treatment of breast cancer.


Assuntos
Hipertermia Induzida , Neoplasias de Mama Triplo Negativas , Anti-Inflamatórios , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Humanos , Verde de Indocianina , Macrófagos , Recidiva Local de Neoplasia/prevenção & controle
18.
Acta Biomater ; 133: 244-256, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34000465

RESUMO

Immune checkpoint blockade treatment is one of the most promising immunotherapies, which exhibits promising therapeutic effects on inhibition of metastasis. However, immunotherapy has little effect on pancreatic cancer, due to its extensive fibrotic matrix and immunosuppressive tumor microenvironment. Mild hyperthermia induced by photothermal therapy (PTT) has been proven to activate the immune responses in the tumor microenvironment. Herein, we designed a combine strategy of mild hyperthermia and immune checkpoint blockade (BMS-202) treatment with size-adjustable thermo- and fibrotic matrix- sensitive liposomes (HSA-BMS@CAP-ILTSL), in which BMS-202 loaded small-sized albumin nanoparticle (HSA-BMS) was encapsulated. Mild hyperthermia reduced the tumor hypoxia, relieved the interstitial pressure and increased the recruitment of endogenous immune cells in tumors. In the meantime, small-sized HSA-BMS was released from large-sized HSA-BMS@CAP-ILTSL in response to fibroblast activation protein-α (FAP-α) and near-infrared (NIR) laser, and enhanced the immunological responses by recovering the activity of T lymphocytes, accompanied by secreting relevant cytokines (TNF-α and IFN-γ). The combined therapy (HSA-BMS@CAP-ILTSL) could not only significantly suppress the tumor growth in vivo, but also decrease the amounts of metastatic nodules in distant organs. These results suggested that size-adjustable nanoparticles had a great potential in the treatment of metastatic pancreatic cancer. STATEMENT OF SIGNIFICANCE: The desmoplastic stroma and hypoperfusion of pancreatic cancer imposed physical barriers to effective therapies, including chemotherapy, radiotherapy, targeted therapy, and immunotherapy. We constructed size-adjustable thermo- and fibrotic matrix- sensitive liposomes (HSA-BMS@CAP-ILTSL) with size around 120 nm, where small sized albumin nanoparticle (10 nm) of immune checkpoint inhibitor (HSA-BMS) were encapsulated inside. Mild hyperthermia not only contributed to release HSA-BMS for penetration (blocking the immunosuppressive signals deep in the tumor), but enhanced tumor blood perfusion for infiltration of endogenous immune cells. In the two-pronged treatment, the pancreatic cancer immunotherapy significantly enhanced and the risk of cancer metastasis was reduced. Overall, the strategy provides a promising approach to increase drug accumulation and improve the anti-tumor immune activity in pancreatic cancer.


Assuntos
Nanopartículas , Neoplasias Pancreáticas , Humanos , Hipertermia , Inibidores de Checkpoint Imunológico , Imunoterapia , Neoplasias Pancreáticas/terapia , Microambiente Tumoral
19.
Acta Biomater ; 134: 546-558, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-33882357

RESUMO

The dilemma of tumor accumulation and deep penetration has always been a barrier in antitumor therapy. Stimuli-responsive size changeable drug delivery systems provide possible solutions. Nevertheless, the low size-shrinkage efficiency limited the antitumor effects. In this study, an instant pH-responsive size shrinkable nanoassemblies named self-aggregated DOX@HA-CD (SA-DOX@HA-CD) was formulated using small-sized hyaluronic acid modified carbon dots (HA-CD) as monomers, which could self-aggregate into raspberry-like structure via hydrophobicity force in neutral pH and rapidly disassemble into shotgun-like DOX-loaded CD monomer in simulated tumor microenvironment (pH 6.5), owing to the transformation in electrical charge and hydrophobicity/hydrophilicity of this system. The transmission electron microscopy showed that the clustered SA-DOX@HA-CD had a diameter of ~150 nm, and thoroughly disassembled into ~30 nm nanoparticles in response to acidic environment. The disassemble efficiency was approximately 100%. Attributed to this property, SA-DOX@HA-CD led to enhanced cellular internalization and accumulation in 4T1 cells in simulated tumor microenvironment, as well as deep tumor penetration in 3D tumor spheroid model. Besides, the imine bond between DOX and HA-CD endowed DOX with pH-responsive release profile in the acidic lysosome environment. Furthermore, in the orthotopic 4T1 tumor-bearing mouse model, SA-DOX@HA-CD demonstrated higher tumor accumulation than non-aggregated DOX-HA-CD. Meanwhile, in response to the acid tumor microenvironment, the dissociated DOX-HA achieved deep tumor penetration, which consequently resulted in 2.5-fold higher antitumor efficiency. The formulation of self-aggregated SA-DOX@HA-CD provides a simple and effective alternative to prepare pH-responsive size-shrinkable nanodrug delivery systems. STATEMENT OF SIGNIFICANCE: The heterogeneity of tumor vasculature and the high tumor interstitial pressure lead to the barriers in tumor accumulation and deep penetration, which calls for opposite properties (e.g. size) of drug delivery systems. To address this dilemma, various size changeable nanoparticles have been developed utilizing special features of tumor microenvironment, such as pH, enzyme and reactive oxygen species. Nevertheless, the current strategies face the problems of incomplete hydrolysis of chemical bonds or insufficient enzyme degradation, which result in only partial size shrinkage, hindering the tumor deep penetration effects. Here we developed a self-assembled nanocluster, which could respond to acidic pH rapidly and thoroughly disassemble into small nanodots due to the alteration of hydrophobicity/hydrophilicity/charge, leading to approximately 100% dissociation. This strategy provides a new concept for design of size changeable drug delivery systems.


Assuntos
Neoplasias da Mama , Nanopartículas , Animais , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Portadores de Fármacos/uso terapêutico , Sistemas de Liberação de Medicamentos , Feminino , Humanos , Concentração de Íons de Hidrogênio , Camundongos , Microambiente Tumoral
20.
Int J Mol Sci ; 22(7)2021 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-33916485

RESUMO

Pax3 and Pax7 are members of the Pax gene family which are essential for embryo and organ development. Both genes have been proved to be markers of muscle satellite cells and play key roles in the process of muscle growth and repair. Here, we identified two Pax3 genes (SsPax3a and SsPax3b) and two Pax7 genes (SsPax7a and SsPax7b) in a marine teleost, black rockfish (Sebastes schlegelii). Our results showed SsPax3 and SsPax7 marked distinct populations of muscle satellite cells, which originated from the multi-cell stage and somite stage, respectively. In addition, we constructed a muscle injury model to explore the function of these four genes during muscle repair. Hematoxylin-eosin (H-E) of injured muscle sections showed new-formed myofibers occurred at 16 days post-injury (dpi). ISH (in situ hybridization) analysis demonstrated that the expression level of SsPax3a and two SsPax7 genes increased gradually during 0-16 dpi and peaked at 16 dpi. Interestingly, SsPax3b showed no significant differences during the injury repair process, indicating that the satellite cells labeled by SsPax3b were not involved in muscle repair. These results imply that the muscle stem cell populations in teleosts are more complicated than in mammals. This lays the foundation for future studies on the molecular mechanism of indeterminant growth and muscle repair of large fish species.


Assuntos
Proteínas de Peixes/metabolismo , Peixes/metabolismo , Músculo Esquelético/fisiologia , Fator de Transcrição PAX3/metabolismo , Fator de Transcrição PAX7/metabolismo , Regeneração/fisiologia , Células Satélites de Músculo Esquelético/metabolismo , Animais , Músculo Esquelético/citologia , Células Satélites de Músculo Esquelético/citologia
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