Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 525
Filtrar
1.
Ecotoxicol Environ Saf ; 276: 116335, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38626603

RESUMO

Urethane hydrolase can degrade the carcinogen ethyl carbamate (EC) in fermented food, but its stability and activity limit its application. In this study, a mutant G246A and a double mutant N194V/G246A with improved cpUH activity and stability of Candida parapsilosis were obtained by site-directed mutagenesis. The catalytic efficiency (Kcat/Km) of mutant G246A and double mutant N194V/G246A are 1.95 times and 1.88 times higher than that of WT, respectively. In addition, compared with WT, the thermal stability and pH stability of mutant G246A and double mutant N194V/G246A were enhanced. The ability of mutant G246A and double mutant N194V/G246A to degrade EC in rice wine was also stronger than that of WT. The mutation increased the stability of the enzyme, as evidenced by decreased root mean square deviation (RMSD) and increased hydrogen bonds between the enzyme and substrate by molecular dynamics simulation and molecular docking analysis. The molecule modification of new cpUH promotes the industrial process of EC degradation.

2.
Zygote ; : 1-8, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38629180

RESUMO

Intracytoplasmic sperm injection (ICSI) is a technique that directly injects a single sperm into the cytoplasm of mature oocytes. Here, we explored the safety of single-sperm cryopreservation applied in ICSI. This retrospective study enrolled 186 couples undergoing ICSI-assisted pregnancy. Subjects were allocated to the fresh sperm (group A)/single-sperm cryopreservation (group B) groups based on sperm type, with their clinical baseline/pathological data documented. We used ICSI-compliant sperm for subsequent in vitro fertilization and followed up on all subjects. The recovery rate/cryosurvival rate/sperm motility of both groups, the pregnancy/outcome of women receiving embryo transfer, and the delivery mode/neonatal-related information of women with successful deliveries were recorded. The clinical pregnancy rate, cumulative clinical pregnancy rate, abortion rate, ectopic pregnancy rate, premature delivery rate, live birth delivery rate, neonatal birth defect rate, and average birth weight were analyzed. The two groups showed no significant differences in age, body mass index, ovulation induction regimen, sex hormone [anti-Müllerian hormone (AMH)/follicle-stimulating hormone (FSH)/luteinizing hormone (LH)] levels, or oocyte retrieval cycles. The sperm recovery rate (51.72%-100.00%) and resuscitation rate (62.09% ± 16.67%) in group B were higher; the sperm motility in the two groups demonstrated no significant difference and met the ICSI requirements. Group B exhibited an increased fertilization rate, decreased abortion rate, and increased safety versus group A. Compared with fresh sperm, the application of single-sperm cryopreservation in ICSI sensibly improved the fertilization rate and reduced the abortion rate, showing higher safety.

3.
J Hazard Mater ; 471: 134273, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38653137

RESUMO

This study employs five UV-AOPs (PMS, PDS, H2O2, NaClO and NaClO2) to produce radicals (•OH, SO4•-, ClO•, O2•- and 1O2) and further comparatively studies their activity sequence and activity difference cause in toluene degradation. The toluene mineralization efficiency as a descending order is 73 % (UV-PMS) > 71 % (UV-PDS) > 70 % (acidified-UV-NaClO) > 55 % (UV-H2O2) > 36 % (UV-NaClO) > 35 % (UV-NaClO2); that of conversion efficiency is 99 % (acidified-UV-NaClO) > 95 % (UV-PMS) > 90 % (UV-PDS) > 74 % (UV-H2O2) > 44 % (UV-NaClO) > 41 % (UV-NaClO2). Acidic pretreatment significantly boosts the reactivity of UV-NaClO. ESR combined with radical quenching tests reveals the radicals' generation and evolution, and their contribution rates to toluene conversion, i.e. ClO• > SO4•- > O2•- > 1O2 > â€¢OH. Theoretical calculations further unveil the ring-opening reaction routes and the nature of the activity difference of different radicals. The minimum energy required for ring-opening reaction is 116.77, 150.63, 168.29 and 191.92 kJ/mol with respect to ClO•, SO4•-, 1O2 and •OH, and finding that the ClO•-HO• pair is the best for toluene mineralization. The difficulty for eliminating typical VOCs by using UV-AOPs method is determined as toluene > chlorobenzene > benzene > ethyl acetate.

4.
BMC Chem ; 18(1): 72, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609951

RESUMO

Toluene, a prominent member of volatile organic compounds (VOCs), exerts a substantial adverse influence on both human life and the environment. In the context of advanced oxidation processes, the ·OH radical emerges as a highly efficient oxidant, pivotal in the elimination of VOCs. This study employs computational quantum chemistry methods (G4MP2//B3LYP/6-311++G(d,p)) to systematically investigate the degradation of toluene by ·OH radicals in an implicit solvent model, and validates the rationale of choosing a single-reference method using T1 diagnostics. Our results suggest three possible reaction mechanisms for the oxidation of toluene by ·OH: firstly, the phenyl ring undergoes a hydrogen abstraction reaction followed by direct combination with ·OH to form cresol; secondly, ·OH directly adds to the phenyl ring, leading to ring opening; thirdly, oxidation of sidechain to benzoic acid followed by further addition and ring opening. The last two oxidation pathways involve the ring opening of toluene via the addition of ·OH, significantly facilitating the process. Therefore, both pathways are considered feasible for the degradation of toluene. Subsequently, the UV-H2O2 system was designed to induce the formation of ·OH for toluene degradation and to identify the optimal reaction conditions. It was demonstrated that ·OH and 1O2 are the primary active species for degrading toluene, with their contribution ranking as ·OH > 1O2. The intermediates in the mixture solution after reactions were characterized using GC-MS, demonstrating the validity of theoretical predictions. A comparative study of the toluene consumption rate revealed an experimental comprehensive activation energy of 10.33 kJ/mol, which is consistent with the preliminary activation energies obtained via theoretical analysis of these three mechanisms (0.56 kJ/mol to 13.66 kJ/mol), indicating that this theoretical method can provide a theoretical basis for experimental studies on the oxidation of toluene by ·OH.

5.
J Agric Food Chem ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38598779

RESUMO

The microbial consortium FA12 that can release ferulic acid (FA) by fermenting distiller's grains was screened from Daqu. Taibaiella, Comamonadaceae, and Ochrobacum were highly abundant in FA12 by 16S rRNA gene sequencing. In the process of long-term acclimation with distiller's grains as a medium, the biomass of FA12 remained stable, and the pH value of fermentation liquid was also relatively stable. Meanwhile, the activities of cellulase, xylanase, and feruloyl esterase secreted by FA12 were stable in the ranges of 0.2350-0.4470, 0.1917-0.3078, and 0.1103-0.1595 U/mL, respectively, and the release of FA could reach 133.77 µg/g. It is proven that the microbial consortium has good genetic stability. In addition, the structural changes of lignocellulose in distiller's grains before and after fermentation were analyzed by scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR), and the changes of distiller's grains weight and lignocellulose content before and after fermentation were also detected. These results all confirmed that FA12 had the function of degrading distiller's grains. In this study, we explored a method to use microbial communities to release FA from distiller's grains and degrade lignocellulose in the waste, which opened up a new way for the application of the high value of lost waste.

6.
Ecotoxicol Environ Saf ; 275: 116275, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38564858

RESUMO

Compound pollution with cadmium (Cd) and zinc (Zn) is common in nature. The effects of compounded Cd and Zn on the growth and development of Iris pseudacorus in the environment and the plant's potential to remediate heavy metals in the environment remain unclear. In this study, the effects of single and combined Cd and Zn stress on I. pseudacorus growth and the enrichment of heavy metals in I. pseudacorus seedlings were investigated. The results showed that under Cd (160 µM) and Zn (800 µM) stress, plant growth was significantly inhibited and photosynthetic performance was affected. Cd+Zn200 (160 µM + 200 µM) reduced the levels of malondialdehyde, hydrogen peroxide, and non-protein thiols by 31.29%, 53.20%, and 13.29%, respectively, in the aboveground tissues compared with levels in the single Cd treatment. However, Cd+Zn800 (160 µM + 800 µM) had no effect. Cd and Zn800 inhibited the absorption of mineral elements, while Zn200 had little effect on plants. Compared with that for Cd treatment alone, Cd + Zn200 and Cd+Zn800 reduced the Cd content in aboveground tissues by 54.15% and 49.92%, respectively, but had no significant effect on Cd in the root system. Zn significantly reduced the Cd content in subcellular components and limited the content and proportion of Cd extracted using water and ethanol. These results suggest that a low supply of Zn reduces Cd accumulation in aboveground tissues by promoting antioxidant substances and heavy metal chelating agents, thus protecting the photosynthetic systems. The addition of Zn also reduced the mobility and bioavailability of Cd to alleviate its toxicity in I. pseudacorus.


Assuntos
Iris (Planta) , Metais Pesados , Poluentes do Solo , Cádmio/toxicidade , Cádmio/análise , Zinco/toxicidade , Desenvolvimento Vegetal , Poluentes do Solo/toxicidade
7.
PLoS One ; 19(4): e0301773, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38593167

RESUMO

Respiratory syncytial virus (RSV) is the leading viral cause of bronchiolitis and pneumonia in infants and toddlers, but there currently is no licensed pediatric vaccine. A leading vaccine candidate that has been evaluated for intranasal immunization in a recently completed phase 1/2 clinical trial is an attenuated version of RSV strain A2 called RSV/ΔNS2/Δ1313/I1314L (hereafter called ΔNS2). ΔNS2 is attenuated by deletion of the interferon antagonist NS2 gene and introduction into the L polymerase protein gene of a codon deletion (Δ1313) that confers temperature-sensitivity and is stabilized by a missense mutation (I1314L). Previously, introduction of four amino acid changes derived from a second RSV strain "line 19" (I79M, K191R, T357K, N371Y) into the F protein of strain A2 increased the stability of infectivity and the proportion of F protein in the highly immunogenic pre-fusion (pre-F) conformation. In the present study, these four "line 19" assignments were introduced into the ΔNS2 candidate, creating ΔNS2-L19F-4M. During in vitro growth in Vero cells, ΔNS2-L19F-4M had growth kinetics and peak titer similar to the ΔNS2 parent. ΔNS2-L19F-4M exhibited an enhanced proportion of pre-F protein, with a ratio of pre-F/total F that was 4.5- to 5.0-fold higher than that of the ΔNS2 parent. The stability of infectivity during incubation at 4°C, 25°C, 32°C and 37°C was greater for ΔNS2-L19F-4M; for example, after 28 days at 32°C, its titer was 100-fold greater than ΔNS2. ΔNS2-L19F-4M exhibited similar levels of replication in human airway epithelial (HAE) cells as ΔNS2. The four "line 19" F mutations were genetically stable during 10 rounds of serial passage in Vero cells. In African green monkeys, ΔNS2-L19F-4M and ΔNS2 had similar growth kinetics, peak titer, and immunogenicity. These results suggest that ΔNS2-L19F-4M is an improved live attenuated vaccine candidate whose enhanced stability may simplify its manufacture, storage and distribution, which merits further evaluation in a clinical trial in humans.


Assuntos
Infecções por Vírus Respiratório Sincicial , Vacinas contra Vírus Sincicial Respiratório , Vírus Sincicial Respiratório Humano , Animais , Humanos , Chlorocebus aethiops , Criança , Vacinas contra Vírus Sincicial Respiratório/genética , Células Vero , Anticorpos Antivirais , Proteínas Virais de Fusão/genética , Vírus Sincicial Respiratório Humano/genética , Anticorpos Neutralizantes , Mutação de Sentido Incorreto
8.
BMC Med Educ ; 24(1): 305, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38504238

RESUMO

BACKGROUND: Laboratory biosafety should be a priority in all healthcare institutions. In traditional laboratory safety teaching students typically receive knowledge passively from their teachers without active involvement. The combination of experiential learning and mobile learning may provide students with greater engagement, retention, and application of knowledge. To address this issue, we developed and conducted a convergent mixed methods study to assess the feasibility and usability of a WeChat mini program (WMP) named WeMed for laboratory biosafety education for medical laboratory students at Guangzhou Medical University (GMU). METHODS: The study was conducted between November 2022 and October 2023 among second-year undergraduate students at GMU. It involved the concurrent collection, analysis, and interpretation of both qualitative and quantitative data to assess feasibility and usability. In the quantitative strand, two evaluations were conducted via online surveys from students (n = 67) after a four-week study period. The System Usability Scale (SUS) was used to evaluate usability, while self-developed questions were used to assess feasibility. Additionally, a knowledge test was administered 6 months after the program completion. In the qualitative strand, fourteen semi-structured interviews were conducted, whereby a reflexive thematic analysis was utilized to analyze the interview data. RESULTS: The overall SUS score is adequate (M = 68.17, SD = 14.39). The acceptability of the WeMed program is in the marginal high range. Most students agreed that WeMed was useful for learning biosafety knowledge and skills (13/14, 93%), while 79% (11/14) agreed it was easy to use and they intended to continue using it. After 6 months, a significant difference in the knowledge test scores was observed between the WeMed group (n = 67; 2nd year students) and the traditional training group (n = 90; 3rd year students). However, the results should be interpreted cautiously due to the absence of a pretest. CONCLUSION: The combination of experiential learning and mobile learning with WMP is a feasible tool for providing laboratory biosafety knowledge and skills. Ongoing improvements should be made in order to increase long-term acceptance.


Assuntos
Estudantes de Medicina , Humanos , Contenção de Riscos Biológicos , Estudos de Viabilidade , Universidades , Aprendizagem
9.
Diabetes Metab Syndr Obes ; 17: 1013-1024, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38481657

RESUMO

Objective: Previous research on the correlation between thyroid function and carotid plaque has revealed conflicting results, possibly attributable to the sensitivity of thyroid hormone indices. In this study, we aimed to analyze the association between thyroid hormone sensitivity indices and the risk of carotid plaque development in a Chinese health check-up population. Methods: A total of 19,388 health check-up subjects were included in this study (mean age: 50.78±10.17 years). Central sensitivity to thyroid hormone was evaluated using the thyroid feedback quantile-based index (TFQI), the Chinese-referenced parametric TFQI (PTFQI), the TSH index (TSHI), and the thyrotropin thyroxine resistance index (TT4RI), while peripheral sensitivity to thyroid hormone was assessed by free triiodothyronine/free thyroxine (FT3/FT4) ratio. Multivariable logistic regression analyses were performed to detect the association between thyroid hormone sensitivity indices and carotid plaque risk, and subgroup analysis was also conducted to explore this association stratified by sex, age, obesity, and the status of smoking, drinking, diabetes, hypertension and dyslipidemia. Results: Among the 19,388 participants, 3753 (19.4%) had carotid plaque. In multivariable adjustment models, the risk of carotid plaque was positively associated with TSHI (odds ratio [OR]: 1.23; 95% confidence interval [CI]: 1.18~1.28), TT4RI (OR: 1.28; 95% CI: 1.23~1.33), TFQI (OR: 1.06; 95% CI: 1.02~1.10), and PTFQI (OR: 1.11; 95% CI: 1.07~1.16), respectively. Conversely, the risk of carotid plaque was negatively correlated with FT3/FT4 (OR: 0.94; 95% CI: 0.90~0.98). In stratified analyses, all thyroid hormone sensitivity indices significantly increased the risk of carotid plaque especially in females, subjects<65 years, non-obese individuals, and those without current smoking, drinking, diabetes, hypertension and dyslipidemia. Conclusion: In Chinese health check-up populations, a considerable connection between reduced sensitivity to thyroid hormones and carotid plaque has been observed, especially in females, those younger than 65 years, non-obese individuals, and those without any current smoking, drinking, diabetes, hypertension, or dyslipidemia.

10.
Environ Pollut ; 345: 123503, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38331243

RESUMO

Methyl jasmonate (MeJA), a crucial phytohormone, which plays an important role in resistance to Cadmium (Cd) stress. The cell wall (CW) of root system is the main location of Cd and plays a key role in resistance to Cd toxicity. However, the mechanism effect of MeJA on the CW composition and Cd accumulation remain unclear. In this study, the contribution of MeJA in regulating CW structure, pectin composition and Cd accumulation was investigated in Cosmos bipinnatus. Phenotypic results affirm MeJA's significant role in reducing Cd-induced toxicity in C. bipinnatus. Notably, MeJA exerts a dual impact, reducing Cd uptake in roots while increasing Cd accumulation in the CW, particularly bound to pectin. The molecular structure of pectin, mainly uronic acid (UA), correlates positively with Cd content, consistent in HC1 and cellulose, emphasizing UA as pivotal for Cd binding. Furthermore, MeJA modulates pectin methylesterase (PME) activity under Cd stress, influencing pectin's molecular structure and homogalacturonan (HG) content affecting Cd-binding capacity. Chelate-soluble pectin (CSP) within soluble pectins accumulates a substantial Cd proportion, with MeJA regulating both UA content and the minor component 3-deoxy-oct-2-ulosonic acid (Kdo) in CSP. The study delves into the intricate regulation of pectin monosaccharide composition under Cd stress, revealing insights into the CW's physical defense and Cd binding. In summary, this research provides novel insights into MeJA-specific mechanisms alleviating Cd toxicity in C. bipinnatus, shedding light on complex interactions between MeJA, and Cd accumulation in CW pectin polysaccharide.


Assuntos
Acetatos , Asteraceae , Cádmio , Ciclopentanos , Oxilipinas , Cádmio/metabolismo , Raízes de Plantas/metabolismo , Polissacarídeos/metabolismo , Polissacarídeos/farmacologia , Pectinas/química , Parede Celular/metabolismo , Asteraceae/metabolismo
11.
Gen Hosp Psychiatry ; 87: 41-47, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38306945

RESUMO

OBJECTIVE: Critical illness survivors frequently experience various degrees of depressive symptoms, which hinder their recovery and return to daily life. However, substantial variability in the prevalence of depressive symptoms has been reported among critical illness survivors. The exact prevalence remains uncertain. METHODS: A systematic search was performed in PubMed, Embase, CINAHL, and PsycINFO from inception to August 2023 for observational studies that reported depressive symptoms in adult critical illness survivors. The random-effects model was used to estimate the prevalence of depressive symptoms. Subgroup analysis and meta-regression were conducted to explore potential moderators of heterogeneity. Study quality was evaluated using the Joanna Briggs Institute's tool and the GRADE approach. RESULTS: Fifty-two studies with 24,849 participants met the inclusion criteria. Overall prevalence estimate of depressive symptoms was 21.1% (95% CI, 18.3-24.1%). The prevalence of depressive symptoms remains stable over time. Point prevalence estimates were 21.3% (95% CI, 9.9-35.4%), 19.9% (95% CI, 14.6-25.9%), 18.5% (95% CI, 9.6-29.2%), 21.0% (95% CI, 16.8-25.5%), and 22.6% (95% CI, 14.4-31.8%) at <3, 3, 6, 12, and > 12 months after discharge from intensive care unit (ICU), respectively. CONCLUSIONS: Depressive symptoms may impact 1 in 5 adult critically ill patients within 1 year or more following ICU discharge. An influx of rehabilitation service demand is expected, and risk stratification to make optimal clinical decisions is essential. More importantly, to propose measures for the prevention and improvement of depressive symptoms in patients after critical care, given the continuous, dynamic management of ICU patients, including ICU stay, transition to general wards, and post-hospital.


Assuntos
Estado Terminal , Depressão , Adulto , Humanos , Estado Terminal/epidemiologia , Depressão/epidemiologia , Unidades de Terapia Intensiva , Cuidados Críticos , Sobreviventes
12.
Support Care Cancer ; 32(3): 146, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38326575

RESUMO

OBJECTIVES: The purpose of this study was to explore the experience of financial toxicity among caregivers of cancer patients and to provide recommendations for subsequent intervention strategies. METHODS: Computer searches of PubMed, EmBase, The Cochrane Library, Web of Science, CINAHL (EBSCO), CNKI, Wanfang database, and SinoMed for qualitative studies experience of financial toxicity among caregivers cancer patients. The search time frame was from the establishment of the database to May 2023. The quality of included studies was assessed using the Qualitative Research Checklist from the Joanna Briggs Institute (JBI) Reviewer's Manual. The meta-synthesis was integrated following the meta-aggregation method proposed by the Joanna Briggs Institute (JBI) and reported following the Enhancing Transparency in Reporting the Synthesis of Qualitative Research (ENTREQ) guidelines. RESULTS: A total of nine studies were included, distilling 25 qualitative findings into nine new categories and synthesizing three synthesized findings: caregivers have strong negative experiences that affect their family relationships, daily work and life; caregivers use different strategies to cope with financial toxicity; needs and expectations of caregivers coping with financial toxicity. CONCLUSIONS: Financial toxicity among caregivers of cancer patients affects their daily lives. Receiving timely recognition of this financial burden and providing assistance to enhance their coping skills are crucial in mitigating its impact. Healthcare professionals should focus on the financial toxicity experienced by caregivers of people with cancer, address their supportive needs, and develop a comprehensive support system to improve caregivers' coping abilities and quality of life.


Assuntos
Cuidadores , Neoplasias , Humanos , Estresse Financeiro , Qualidade de Vida , Pesquisa Qualitativa , Neoplasias/terapia
13.
Small ; : e2309293, 2024 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-38342681

RESUMO

In recent years, carbon dots (CDs) have garnered increasing attention due to their simple preparation methods, versatile performances, and wide-ranging applications. CDs can manifest various optical, physical, and chemical properties including quantum yield (QY), emission wavelength (Em), solid-state fluorescence (SSF), room-temperature phosphorescence (RTP), material-specific responsivity, pH sensitivity, anti-oxidation and oxidation, and biocompatibility. These properties can be effectively regulated through precise control of the CD preparation process, rendering them suitable for diverse applications. However, the lack of consideration given to the precise control of each feature of CDs during the preparation process poses a challenge in obtaining the requisite features for various applications. This paper is to analyze existing research and present novel concepts and ideas for creating CDs with different distinct features and applications. The synthesis methods of CDs are discussed in the first section, followed by a comprehensive overview of the important properties of CDs and the modification strategy. Subsequently, the application of CDs and their requisite properties are reviewed. Finally, the paper outlines the current challenges in controlling CDs properties and their applications, discusses potential solutions, and offers suggestions for future research.

14.
Analyst ; 149(4): 1271-1279, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38226548

RESUMO

T4 polynucleotide kinase helps with DNA recombination and repair. In this study, an electrochemical biosensor was developed for a T4 polynucleotide kinase activity assay and inhibitor screening based on phosphate pillar[5]arene and multi-walled carbon nanotube nanocomposites. The water-soluble pillar[5]arene was employed as the host to complex thionine guest molecules. The substrate DNA with a 5'-hydroxyl group initially self-assembled on the gold electrode surface through chemical adsorption of the thiol group, which was phosphorylated in the presence of T4 polynucleotide kinase. Titanium dioxide nanoparticles served as a bridge to link phosphorylated DNA and phosphate pillar[5]arene and multi-walled carbon nanotube composite due to strong phosphate-Ti4+-phosphate chemistry. Through supramolecular host-guest recognition, thionine molecules were able to penetrate the pillar[5]arene cavity, resulting in an enhanced electrochemical response signal. The electrochemical signal is proportional to the T4 polynucleotide kinase concentration in the range of 10-5 to 15 U mL-1 with a detection limit of 5 × 10-6 U mL-1. It was also effective in measuring HeLa cell lysate-related T4 polynucleotide kinase activity and inhibitor screening. The proposed method offers a unique sensing platform for kinase activity measurement, holding great potential in nucleotide kinase-target drug development, clinical diagnostics, and inhibitor screening.


Assuntos
Técnicas Biossensoriais , Nanotubos de Carbono , Fenotiazinas , Humanos , Polinucleotídeo 5'-Hidroxiquinase , Nanotubos de Carbono/química , Fosfatos , Células HeLa , DNA/química , Técnicas Biossensoriais/métodos
15.
Carbohydr Polym ; 327: 121624, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38171652

RESUMO

Herein, a series of water-soluble supramolecular inclusion complexes (ICs) probes were prepared using cyclodextrins (CDs) and fraxetin (FRA) to detect nicotine (NT) with high selectivity in vitro and in vivo. The FRA/CD ICs prepared through the saturated solution method exhibited excellent water solubility, stability, and biocompatibility. A clear host-guest inclusion model was provided by the theoretical calculations. The investigation revealed that NT was able to enter into the cavities of FRA/ß-CD IC and FRA/γ-CD IC, and further formed charge transfer complexes with FRA in the CD cavities, resulting in a rapid and highly selective fluorescence-enhanced response with the lowest detection limits of 1.9 × 10-6 M and 9.7 × 10-7 M, and the linear response ranged from 0.02 to 0.3 mM and 0.01-0.05 mM, respectively. The IC probes showed good anti-interference performance to common interferents or different pH environments, with satisfactory reproducibility and repeatability of response to NT. Furthermore, the potentiality of the probes was confirmed through fluorescence imaging experiments using human lung cancer cells and the lung tissue of mice. This study offers a fresh perspective for detecting NT in environmental and biomedical analysis.


Assuntos
Ciclodextrinas , Animais , Camundongos , Humanos , Ciclodextrinas/química , Nicotina , Reprodutibilidade dos Testes , Água/química , Solubilidade
16.
Environ Res ; 243: 117813, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38043893

RESUMO

Terrestrial gross primary production (GPP) changes due to impervious surfaces significantly impact ecosystem services in watersheds. Understanding the asymmetric response of vegetation GPP to impervious surface expansion is essential for regional development planning and ecosystem management. However, the asymmetric response of vegetation GPP to the impacts of impervious surface expansion is unknown in different watersheds. This paper selected the Yellow River and Yangtze River basins as case studies. We characterized the overall change in GPP based on changes in impervious surface ratio (ISR), determined impervious surface expansion's direct and indirect impacts on GPP in the two watersheds, and further analyzed the asymmetric response of the compensatory effects of indirect influences on the impervious surface expansion in different watersheds. The results showed that: (1) The vegetation GPP decreased with increasing ISR in the Yangtze River Basin, while that in the Yellow River Basin first increased and then reduced. (2) The direct impacts of increased ISR reduced vegetation GPP, while the indirect impacts both had a growth-compensating effect. Growth compensation stabilized at approximately 0.40 and 0.30 in the Yellow and Yangtze River Basins. (3) When the ISR was 0.34-0.56, the growth compensation could offset the reduction of GPP due to direct impact and ensure that the background vegetation GPP was not damaged in the Yellow River Basin. In contrast, the background vegetation GPP was inevitably impaired with increased ISR in the Yangtze River Basin. Therefore, this study suggests that the ISR should be ensured to be between 0.34 and 0.56 to maximize the impervious surface of the Yellow River Basin without compromising the background vegetation GPP. While pursuing impervious surface expansion in the Yangtze River Basin, other programs should be sought to compensate for the loss to GPP.


Assuntos
Ecossistema , Monitoramento Ambiental , Rios , China
17.
Neuromodulation ; 27(2): 302-311, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36740464

RESUMO

BACKGROUND: Inflammatory bowel disease (IBD) is characterized by chronic progressive intestinal inflammation. Sacral nerve stimulation (SNS) ameliorates colon inflammation caused by IBD. The aim of this study was to investigate the antiinflammatory benefits of SNS in colitis rats and explore the roles of the cholinergic antiinflammatory pathway, macrophage autophagy, and nucleotide oligomerization domain-like receptor thermal protein domain associated protein 3 (NLRP3) inflammatory bodies. MATERIALS AND METHODS: Rats were divided into four groups: healthy control, dextran sulfate sodium (DSS), DSS + sham-SNS, and DSS + SNS groups. An electrode was surgically placed in the right sacral nerve (S3) for stimulation. The disease activity index (DAI) score was recorded each day, and the degree of inflammatory injury was evaluated using hematoxylin and eosin staining. The alpha7 nicotinic acetylcholine receptor (α7nAChR) and autophagy- and NLRP3-related factors were assessed using immunofluorescence staining and Western blotting. RESULTS: The DSS group showed a higher DAI score, colon shortening, upregulated proinflammatory action, and colon damage, and the DSS + SNS group showed significantly improved symptoms. The number of α7nAChR+ cells and the expression level of autophagy decreased in the DSS group but increased in the DSS + SNS group. Conversely, the DSS group showed increased activation of NLRP3 inflammatory bodies, whereas the DSS + SNS group showed decreased activation of NLRP3 inflammatory bodies. CONCLUSION: In this study, SNS ameliorated colon inflammation by enhancing macrophage autophagy and inhibiting the activation of NLRP3 inflammatory bodies, which may be related to the opening of the cholinergic antiinflammatory pathway.


Assuntos
Colite , Doenças Inflamatórias Intestinais , Ratos , Animais , Camundongos , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Colite/induzido quimicamente , Colite/terapia , Colite/metabolismo , Doenças Inflamatórias Intestinais/metabolismo , Inflamação/terapia , Inflamação/metabolismo , Macrófagos/metabolismo , Autofagia , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Colo
18.
Int J Biol Macromol ; 254(Pt 3): 128052, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37967602

RESUMO

Typically, the tailorable versatility of biomass aerogels is attributed to the tunable internal molecular structure, providing broad application prospects. Herein, a simple and novel preparation strategy for developing multifunctional dual-network chitosan/itaconic acid (CSI) aerogel with tunability by using freeze-drying and vacuum heat treatment techniques. By regulating the temperature and duration of amidation reaction, electrostatic interactions between chitosan (CS) and itaconic acid (IA) was abstemiously converted into amide bond in frozen aerogel, with IA acting as an efficient in-situ cross-linking agent, which yielded CSI aerogels with different electrostatic/covalent cross-linking ratios. Heat treatment and tuning of the covalent cross-linking degree of CSI aerogel changed their microstructure and density, which led to enhanced performance. For example, the specific modulus of CSI1.5-160 °C-5 h (71.69 ± 2.55 MPa·cm3·g-1) increased by 119 % compared to that of CSI1.5 (32.73 ± 0.718 MPa·cm3·g-1), converting the material from superhydrophilic to hydrophobic (124° ± 3.6°), exhibiting favorable stability and heat transfer performance. In addition, part of -NH3+ of CS was retained in the electrostatic cross-linked network, endowing the aerogel with antibacterial properties. The findings of this study provide insights and a reliable strategy for fabricating biomass aerogel with good comprehensive performance via ingenious structural design and simple regulation methods.


Assuntos
Quitosana , Amidas , Antibacterianos , Biomassa
19.
Adv Healthc Mater ; : e2302893, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38060694

RESUMO

Bandages for daily wounds are the most common medical supplies, but there are still ingrained defects in their appearance, comfort, functions, as well as environmental pollution. Here, novel bandages based on bacterial cellulose (BC) membrane for wound monitoring and advanced wound management are developed. The BC membrane is combined with silver nanowires (AgNWs) by using vacuum filtration method to achieve transparent, ultrathin (≈7 µm), breathable (389.98-547.79 g m-2  d-1 ), and sandwich-structured BC/AgNWs bandages with superior mechanical properties (108.45-202.35 MPa), antibacterial activities against Escherichia coli and Staphylococcus aureus, biocompatibility, and conductivity (9.8 × 103 -2.0 × 105  S m-1 ). Significantly, the BC/AgNWs bandage is used in the electrical stimulation (direct current, 600  microamperes for 1 h every other day) treatment of full-thickness skin defect in rats, which obviously promotes wound healing by increasing the secretion of vascular endothelial growth factor (VEGF). The BC bandage is used for monitoring wounds and achieve a high accuracy of 94.7% in classifying wound healing stages of hemostasis, inflammation, proliferation, and remodeling, by using a convolutional neural network. The outcomes of this study not only provide two BC-based bandages as multifunctional wound management, but also demonstrate a new strategy for the development of the next generation of smart bandage.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...