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1.
Environ Sci Technol ; 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39352087

RESUMO

Commercial herbicides, particularly sulfonylureas, are used worldwide and pose a significant challenge to environmental sustainability. The efficient degradation of sulfonylurea herbicides is critical. SulE, an esterase isolated from the bacterial strain Hansschlegelia zhihuaiae S113, shows degradation activity toward sulfonylurea herbicides. However, the detailed catalytic mechanism remains vague to a large extent. Herein, we decipher the SulEP44R-catalyzed degradation mechanism of sulfonylurea herbicides using hybrid quantum mechanics and molecular mechanics approaches. Our results show that the degradation of sulfonylureas catalyzed by SulEP44R involves four concerted elementary steps. The rate-determining step has an energy barrier range of 19.7-21.4 kcal·mol-1, consistent with the experimentally determined range of 16.0-18.0 kcal·mol-1. Distortion/interaction analysis demonstrates that active-site amino acids play a vital role in the enzymatic catalytic efficacy. The unique architecture of SulEP44R's active site can serve as an excellent template for designing artificial catalysts. Key structural and charge parameters affecting catalytic activity were systematically screened and identified. Based on the elucidated degradation mechanism, several new herbicides with both high herbicidal activity and biodegradability were developed with the aid of a high-throughput strategy. Our findings may advance the application of sulfonylurea herbicides within the framework of environmental sustainability.

2.
Heliyon ; 10(16): e36495, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39253173

RESUMO

Zebrafish is a highly advantageous model animal for drug screening and toxicity evaluation thanks to its amenability to optical imaging (i.e., transparency), possession of organ structures similar to humans, and the ease with which disease models can be established. However, current zebrafish drug screening technologies and devices suffer from limitations such as low level of automation and throughput, and low accuracy caused by the heterogeneity among individual zebrafish specimens. To address these issues, we herein develop a high-throughput zebrafish drug screening system. This system is capable of maintaining optimal culturing conditions and simultaneously monitoring and analyzing the movement of 288 zebrafish larvae under various external conditions, such as drug combinations. Moreover, to eliminate the effect of heterogeneity, locomotion of participating zebrafish is assessed and grouped before experiments. It is demonstrated that in contrast to the experimental results without pre-selection, which shows ∼20 % damaged motor function (i.e., degree of attenuation), the drug-induced variations among zebrafish with equivalent mobility reaches ∼80 %. Overall, our high-throughput zebrafish drug screening system overcomes current limitations by improving automation, throughput, and accuracy, resulting in enhanced detection of drug-induced variations in zebrafish motor function.

3.
Environ Sci Technol ; 58(39): 17334-17343, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39292760

RESUMO

Carbonyl compounds play a crucial role in the formation of ozone (O3) and secondary aerosols, with recent studies particularly highlighting formaldehyde (HCHO) as a significant contributor to the missing particulate sulfur. However, evaluations based on field observations are limited, especially in clean marine environments. Utilizing observation data from a coastal mountain site in May 2021 in Qingdao, northern China, we reveal the important regulating effect of carbonyls in atmospheric oxidation capacity and particulate sulfur chemistry using detailed chemical box models. Photolysis of gaseous carbonyls accounted for >90% and >60% of the primary sources of HO2 and RO2, respectively, contributing 38% of net O3 production. Notably, HCHO alone constituted 80% of the primary HO2 and 15% of net O3 production. Using a multiphase model with updated HCHO-related chemistry, we determine that HCHO chemistry can account for up to 30% of total particulate sulfur (the sum of hydroxymethanesulfonate and sulfate) and address more than one-third of the simulated sulfate gap. The emission-based multiphase model indicates that the HCHO-related pathway remains significant and can account for 20% of the particulate sulfur under clean marine conditions. These findings underscore the importance of carbonyls, particularly HCHO, in regulating the atmospheric oxidation capacity and particulate sulfur chemistry in the marine atmosphere, urging further laboratory studies on chemical kinetics and field measurements of particle-phase carbonyls.


Assuntos
Atmosfera , Oxirredução , Enxofre , Atmosfera/química , Enxofre/química , Ozônio/química , Poluentes Atmosféricos/química , Aerossóis , China , Material Particulado
4.
Adv Sci (Weinh) ; : e2406656, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39248322

RESUMO

The inhibition of Nav1.7 is a promising strategy for the development of analgesic treatments. Spider venom-derived peptide toxins are recognized as significant sources of Nav1.7 inhibitors. However, their development has been impeded by limited selectivity. In this study, eight peptide toxins from three distinct spider venom Nav channel families demonstrated robust inhibition of hNav1.7, rKv4.2, and rKv4.3 (rKv4.2/4.3) currents, exhibiting a similar mode of action. The analysis of structure and function relationship revealed a significant overlap in the pharmacophore responsible for inhibiting hNav1.7 and rKv4.2 by HNTX-III, although Lys25 seems to play a more pivotal role in the inhibition of rKv4.2/4.3. Pharmacophore-guided rational design is employed for the development of an mGpTx1 analogue, mGpTx1-SA, which retains its inhibition of hNav1.7 while significantly reducing its inhibition of rKv4.2/4.3 and eliminating cardiotoxicity. Moreover, mGpTx1-SA demonstrates potent analgesic effects in both inflammatory and neuropathic pain models, accompanied by an improved in vivo safety profile. The results suggest that off-target inhibition of rKv4.2/4.3 by specific spider peptide toxins targeting hNav1.7 may arise from a conserved binding motif. This insight promises to facilitate the design of hNav1.7-specific analgesics, aimed at minimizing rKv4.2/4.3 inhibition and associated toxicity, thereby enhancing their suitability for therapeutic applications.

5.
Wei Sheng Yan Jiu ; 53(4): 592-607, 2024 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-39155227

RESUMO

OBJECTIVE: To investigate the prevalence of hyperuricemia among freshmen enrolled in Beijing Sport University and to explore the influencing factors of hyperuricemia in the college population. METHODS: The study period was from September 2021 to February 2022.3372 freshmen of the class of 2021 from Beijing Sport University in Beijing were selected as the study subjects, and two blood uric acid tests were performed on non-same days to calculate the prevalence of the population and to explore the risk factors of hyperuricemia in the college student population using a case-control method.246 people were selected from the hyperuricemia patients of the population to be included in the case group by convenience sampling, and 211 people were selected from the non-hyperuricemia persons of the population to be included in the control group. They were included in the control group, underwent physical and laboratory examinations, and were retrospectively surveyed with questionnaires that included general information such as age, gender, specialty, place of birth, and diet related to hyperuricemia, awareness of hyperuricemia disease, physical activity level, and sleep. Statistical analysis was performed using chi-square analysis, one-way Logistic regression analysis, and multi-factor logistic regression analysis. RESULTS: The number of patients actually diagnosed with hyperuricemia by two blood uric acid tests on non-same days was 479, with a population prevalence rate of 14.21%. Among them, the number of males in the diseased population was 391(22.39%), and the number of females in the diseased population was 88(5.41%). A total of 457 subjects were enrolled in the case-control study, among them, 246 in the case group(218 males and 28 females, average age 19.74 years), 211 in the control group(177 males and 34 females, average age 19.93 years), and 247 in the case group, 211 in the control group, and 2 groups of subjects were included. A total of 211 subjects, and there was no significant difference between the 2 groups in terms of gender composition and age distribution. One-way logistic regression analysis showed that central obesity(OR=31.52, 95%CI 7.59-130.86), obesity(OR=2.59, 95%CI 1.20-5.58), overweight(OR=1.67, 95%CI 1.08-2.59), frequent consumption of fresh vegetables(OR=0.66, 95%CI 0.43-0.99), and drinking 1500-2000 mL of water per day(OR=0.63, 95%CI 0.41-0.95) were associated with hyperuricemia, and multifactorial Logistic regression analyses were performed to analyze the above factors, and finally central obesity(OR=32.05, 95%CI 7.65-134.20), BMI obesity(OR=3.22, 95%CI 1.44-7.20), and daily water intake of 1500-2000 mL(OR=0.60, 95%CI 0.37-0.95) were included in the model at the level of P=0.05. CONCLUSION: The current high prevalence of hyperuricemia in the college student population, which is more prevalent in male college students. Obesity and central obesity are risk factors for hyperuricemia in young college students, and daily water intake of 1500-2000 mL is a protective factor.


Assuntos
Hiperuricemia , Estudantes , Ácido Úrico , Humanos , Hiperuricemia/epidemiologia , Hiperuricemia/etiologia , Masculino , Fatores de Risco , Prevalência , Feminino , Universidades , Estudantes/estatística & dados numéricos , Adulto Jovem , Estudos de Casos e Controles , Ácido Úrico/sangue , Inquéritos e Questionários , Pequim/epidemiologia , Adulto , Estudos Retrospectivos , Adolescente , China/epidemiologia
6.
J Hazard Mater ; 477: 135414, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39102770

RESUMO

Polyethylene terephthalate (PET) is a widely used material in our daily life, particularly in areas such as packaging, fibers, and engineering plastics. However, PET waste can accumulate in the environment and pose a great threat to our ecosystem. Recently enzymatic conversion has emerged as an efficient and green strategy to address the PET crisis. Here, using a theoretical approach combining molecular dynamics simulation and quantum mechanics/molecular mechanics calculations, the depolymerization mechanism of the thermophilic cutinase BhrPETase was fully deciphered. Surprisingly, unlike the previously studied cutinase LCCICCG, our results indicate that the first step, catalytic triad assisted nucleophilic attack, is the rate-determining step. The corresponding Boltzmann weighted average energy barrier is 18.2 kcal/mol. Through extensive comparison between BhrPETase and LCCICCG, we evidence that key features like charge CHis@N1 and angle APET@C1-Ser@O1-His@H1 significantly impact the depolymerization efficiency of BhrPETase. Non-covalent bond interaction and distortion/interaction analysis inform new insights on enzyme engineer and may aid the recycling of enzymatic PET waste. This study will aid the advancement of the plastic bio-recycling economy and promote resource conservation and reuse.

7.
Lipids Health Dis ; 23(1): 176, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38851714

RESUMO

BACKGROUND: Remnant cholesterol (RC) is an important marker for assessing the risk of metabolic syndrome. However, the correlation between RC and hyperuricemia (HUA) remains unclear. This study aimed to explore the correlation between RC and HUA in American adults. METHODS: A total of 9089 participants from the 2013-2020 National Health and Nutrition Examination Survey were investigated. The correlation between RC and the odds of HUA was evaluated using multivariate logistic regression analysis. The nonlinear correlation was described using fitted smoothed curves. The correlation in subgroups was analyzed based on race, gender, alcohol consumption, age, body mass index, waist circumference, diabetes and moderate physical activities. RESULTS: RC was correlated with uric acid (Spearman's correlation coefficient = 0.208 in males and 0.215 in females; all P < 0.001). Multiple logistic regression analysis indicated a positive correlation between RC and the risk of HUA (odds ratio = 1.022 in males and 1.031 in females; all P < 0.001). Subgroup analysis revealed that the correlation was stronger in females, participants aged < 50 years, and those without diabetes. Furthermore, the generalized smooth curve fitting demonstrated a linear correlation between RC and HUA, without threshold or saturation effects. CONCLUSION: Elevated RC significantly and positively correlated with HUA in American adults. This correlation was stronger among females, participants aged < 50 years, and those without diabetes.


Assuntos
Colesterol , Hiperuricemia , Inquéritos Nutricionais , Ácido Úrico , Humanos , Masculino , Feminino , Hiperuricemia/sangue , Hiperuricemia/epidemiologia , Pessoa de Meia-Idade , Adulto , Colesterol/sangue , Ácido Úrico/sangue , Estados Unidos/epidemiologia , Fatores de Risco , Modelos Logísticos , Idoso , Índice de Massa Corporal , Circunferência da Cintura , Razão de Chances , Triglicerídeos/sangue , Síndrome Metabólica/sangue , Síndrome Metabólica/epidemiologia
8.
J Hazard Mater ; 474: 134797, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38865921

RESUMO

Poly(butylene adipate-co-terephthalate) (PBAT) is widely utilized in the production of food packaging and mulch films. Its extensive application has contributed significantly to global solid waste, posing numerous environmental challenges. Recently, enzymatic recycling has emerged as a promising eco-friendly solution for the management of plastic waste. Here, we systematically investigate the depolymerization mechanism of PBAT catalyzed by cutinase TfCutSI with molecular docking, molecular dynamics simulations, and quantum mechanics/molecular mechanics calculations. Although the binding affinities for acid ester and terephthalic acid ester bonds are similar, a regioselective depolymerization mechanism and a "chain-length" effect on regioselectivity were proposed and evidenced. The regioselectivity is highly associated with specific structural parameters, namely Substrate@O4-Met@H7 and Substrate@C1-Ser@O1 distances. Notably, the binding mode of BTa captured by X-ray crystallography does not facilitate subsequent depolymerization. Instead, a previously unanticipated binding mode, predicted through computational analysis, is confirmed to play a crucial role in BTa depolymerization. This finding proves the critical role of computational modelling in refining experimental results. Furthermore, our results revealed that both the hydrogen bond network and enzyme's intrinsic electric field are instrumental in the formation of the final product. In summary, these novel molecular insights into the PBAT depolymerization mechanism offer a fundamental basis for enzyme engineering to enhance industrial plastic recycling.


Assuntos
Simulação de Acoplamento Molecular , Poliésteres , Polimerização , Poliésteres/química , Poliésteres/metabolismo , Simulação de Dinâmica Molecular , Ácidos Ftálicos/química , Ácidos Ftálicos/metabolismo , Estereoisomerismo , Hidrolases de Éster Carboxílico
9.
Sci Total Environ ; 946: 174108, 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-38914328

RESUMO

Comprehensive volatile organic compounds (VOCs) emission control is imperative to decreasing occupational health risks and environmental impact of the packaging and printing industries. In this work, we investigated the VOCs emission characteristics and concentrations of individual contaminants generated by the packaging and printing industries, with regard to various categories, processes, and geographic regions. VOCs emissions, ozone formation potential (OFP), and associated health risks were assessed at 10 representative packaging and printing firms across several cities in Shandong Province, China. Plastic packaging enterprises had the greatest levels of unorganized VOCs emissions, consisting predominantly of oxygenated volatile organic compounds (OVOCs), followed by alkanes and halocarbons. From metal and paper packaging enterprises, OVOCs, alkanes, and aromatics were significant components of unorganized VOCs emissions. Aromatics, halocarbons, and OVOCs contributed significantly to OFP in workshops. The potential carcinogenic risk associated with VOCs in the packaging and printing industries was not significant. However, according to the findings in this study, the workshop environment may provide a comparatively elevated non-carcinogenic risk attributable to ethyl acetate, isopropanol, acrolein, 1,1,2-Trichloroethane, 1,2-Dichloropropane, and naphthalene exposure. In particular, the endocrine-disrupting and genetic toxic effects caused by benzene, toluene, styrene, and naphthalene should not be overlooked. Thus, it is essential to provide precedence to the working environment conditions of workshop laborers, while also undertaking scientific and systematic measures to mitigate the detrimental impacts of VOCs on the environment and human welfare.


Assuntos
Compostos Orgânicos Voláteis , Compostos Orgânicos Voláteis/análise , China , Monitoramento Ambiental , Medição de Risco , Impressão , Embalagem de Produtos , Humanos , Poluentes Atmosféricos/análise , Exposição Ocupacional/análise , Poluentes Ocupacionais do Ar/análise
10.
Sci Total Environ ; 945: 174107, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38908598

RESUMO

Nitrate (NO3-) has been identified as a key component of particulate matter (PM2.5) in China. However, there is still a lack of understanding regarding its sources and how it forms, especially in the context of high-frequency and long-term data. In this study, NO3- levels were observed on an hourly basis over an almost three-year period at an urban site in the Pearl River Delta (PRD) region, China, from January 2019 to December 2021. The results reveal an average daily NO3- concentration ranging from 0.08 µg m-3 to 61.69 µg m-3, constituting 11.9 ± 12.5 % of PM2.5. This percentage rose to as high as 57 % during pollution episodes, highlighting NO3-'s significant role in pollution formation. The ammonia-rich environment was found to be the most important factor in promoting NO3- formation. Positive Matrix Factorization (PMF) analysis indicates that the primary sources of NO3- in the PRD region were vehicle emissions (43.8 ± 21.2 %) and coal combustion (39.1 ± 21.5 %), with shipping emissions, sea salt, soil dust and industrial emissions + biomass burning following in importance. Regarding source areas, the primary contributor of vehicle emissions was predominantly from the PRD region, whereas the coal combustion, aside from local contributions, also originates from the northern region. From a long-term perspective, NO3- pollution has remained relatively stable since the summer of 2020. Concurrently, coal combustion source has shown a localization trend. These insights derived from the extensive, high-frequency observation presented in this study serve as a valuable reference for devising strategies to control NO3- and PM2.5 in the PRD region and China.

11.
Artigo em Inglês | MEDLINE | ID: mdl-38904897

RESUMO

Enterococcus faecium, Bifidobacterium, and Pediococcus acidilactici, as intestinal probiotics, have been proved to play a positive role in treating intestinal diseases, promoting growth and immune regulation in poultry. The aim of this study was to evaluate the effect of compound probiotics on growth performance, digestive enzyme activity, intestinal microbiome characteristics, as well as intestinal morphology in broiler chickens. Treatment diets with chlortetracycline and compound probiotics were used for two groups of sixty broilers each throughout the feeding process. Another group was fed the basal diet. The BW (2589.41 ± 13.10 g vs 2422.50 ± 19.08 g) and ADG (60.57 ± 0.31 g vs 56.60 ± 0.45 g) of the compound probiotics added feed treatment group were significantly increased, and the FCR was significantly decreased (P < 0.05). The supplementation of a compound probiotics enhanced the abundance of beneficial bacteria such as Lactobacillus, Faecalibacterium, and norank_f_norank_o_Clostridia_vadinBB60_group (P < 0.05), and modulated the cecal microbiota structure, thereby promoting the production of short-chain fatty acids (SCFAs) and elevating their levels (P < 0.05), particularly propionic and butyric acids. Furthermore, the administration of the compound probiotics supplements significantly enhanced the villi height, V/C ratio, and reduced the crypt depth (P < 0.05). In addition, the activity of digestive enzymes in the duodenum and jejunum was elevated (P < 0.05). Collectively, the selected compound probiotics supplemented in this experiment have demonstrated efficacy, warranting further application in practical production settings as a viable alternative to antibiotics, thereby facilitating efficient production and promoting gastrointestinal health.

12.
Chemosphere ; 358: 142238, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38705413

RESUMO

Predicting the metabolic activation mechanism and potential hazardous metabolites of environmental endocrine-disruptors is a challenging and significant task in risk assessment. Here the metabolic activation mechanism of benzophenone-3 catalyzed by P450 1A1 was investigated by using Molecular Dynamics, Quantum Mechanics/Molecular Mechanics and Density Functional Theory approaches. Two elementary reactions involved in the metabolic activation of BP-3 with P450 1A1: electrophilic addition and hydrogen abstraction reactions were both discussed. Further conversion reactions of epoxidation products, ketone products and the formaldehyde formation reaction were investigated in the non-enzymatic environment based on previous experimental reports. Binding affinities analysis of benzophenone-3 and its metabolites to sex hormone binding globulin indirectly demonstrates that they all exhibit endocrine-disrupting property. Toxic analysis shows that the eco-toxicity and bioaccumulation values of the benzophenone-3 metabolites are much lower than those of benzophenone-3. However, the metabolites are found to have skin-sensitization effects. The present study provides a deep insight into the biotransformation process of benzophenone-3 catalyzed by P450 1A1 and alerts us to pay attention to the adverse effects of benzophenone-3 and its metabolites in human livers.


Assuntos
Benzofenonas , Citocromo P-450 CYP1A1 , Disruptores Endócrinos , Benzofenonas/metabolismo , Disruptores Endócrinos/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Teoria Quântica , Humanos , Simulação de Dinâmica Molecular , Catálise , Biotransformação
13.
Asian J Neurosurg ; 19(1): 26-36, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38751389

RESUMO

Objective Early exposure to niche specialities, like neurosurgery, is essential to inform decisions about future training in these specialities. This study assesses the impact of a hands-on simulated aneurysm clipping workshop on medical students' and junior doctors' perceptions of neurosurgery at a student-organized neurosurgical conference. Methods Ninety-six delegates were sampled from a hands-on workshop involving hydrogel three-dimensional printed aneurysms clipping using surgical microscopes. Consultant neurosurgeons facilitated the workshop. Changes in delegates' perceptions of neurosurgery were collected using Likert scale and free-text responses postconference. Results Postworkshop, 82% of participants reported a positive impact on their perception of neurosurgery. Thematic analysis revealed that delegates valued the hands-on experience, exposure to microsurgery, and interactions with consultant neurosurgeons. Thirty-six of the 96 delegates (37.5%) expressed that the workshop dispelled preconceived fears surrounding neurosurgery and improved understanding of a neurosurgeon's day-to-day tasks. Several delegates initially apprehensive about neurosurgery were now considering it as a career. Conclusion Hands-on simulated workshops can effectively influence medical students' and junior doctors' perceptions of neurosurgery, providing valuable exposure to the specialty. By providing a valuable and immersive introduction to the specialty, these workshops can help to dispel misconceptions, fears, and apprehensions associated with neurosurgery, allowing them to consider the specialty to a greater degree than before. This study of a one-time workshop cannot effectively establish its long-term impact on said perceptions, however.

14.
Chemosphere ; 359: 142228, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38705407

RESUMO

Copper oxides are vital catalysts in facilitating the formation of polychlorinated thianthrenes/dibenzothiophenes (PCTA/DTs) through heterogeneous reactions in high-temperature industrial processes. Chlorothiophenols (CTPs) are the most crucial precursors for PCTA/DT formation. The initial step in this process is the metal-catalyzed production of chlorothiophenoxy radicals (CTPRs) from CTPs via dissociation reactions. This work combines density functional theory (DFT) calculations with ab initio molecular dynamics (AIMD) simulations to explore the formation mechanism of the adsorbed 2-CTPR from 2-CTP, with the assistance of CuO(111). Our study demonstrates that flat adsorption configurations of 2-CTP on the CuO(111) surface are more stable than vertical configurations. The CuO(111) surface acts as a strong catalyst, facilitating the dissociation of 2-CTP into the adsorbed 2-CTPR. Surface oxygen vacancies enhance the adsorption of 2-CTP on the CuO(111) surface, while moderately suppressing the dissociation of 2-CTP. More importantly, water molecules and surface hydroxyl groups actively promote the dissociation of 2-CTP. Specifically, water directly participates in the reaction through "water bridge", enabling a barrier-free process. This research provides molecular-level insights into the heterogeneous generation of dioxins with the catalysis of metal oxides in fly ash from static and dynamic aspects, providing novel approaches for reducing dioxin emissions and establishing dioxin control strategies.


Assuntos
Cobre , Teoria da Densidade Funcional , Cobre/química , Adsorção , Catálise , Água/química , Simulação de Dinâmica Molecular , Hidróxidos/química , Propriedades de Superfície , Compostos de Sulfidrila/química
15.
Sci Total Environ ; 937: 173182, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-38740192

RESUMO

Organophosphate flame retardants (OPFRs) are widely used as alternatives to brominated flame retardants in a variety of consumer products and their consumption has continuously increased in recent years. However, their concentrations and human exposures in indoor microenvironments, particularly in a university environment, have received limited attention. In this study, the concentrations and seasonal variations of 15 OPFRs were assessed in typical microenvironments of two universities, including dormitories, offices, public microenvironments (PMEs: classroom, dining hall, gymnasium and library), and laboratories on the northern coast of China. Analysis of the OPFRs in both air and dust samples indicated widespread distribution in college campuses. The average concentration of ∑15OPFRs in the winter (12,774.4 ng/g and 5.3 ng/m3 for dust and air, respectively) was higher than in the summer (2460.4 ng/g and 4.6 ng/m3 for dust and air, respectively). The dust and air samples collected from PMEs and laboratories exhibited higher concentrations of OPFRs, followed by offices and dormitories. An equilibrium was reached between dust and air in all collected microenvironments. The daily intakes of OPFRs were significantly lower than the reference dose. Dust ingestion was the primary intake pathway in the winter, while inhalation and dust ingestion were the main intake pathways in the summer. The non-carcinogenic hazard quotients fell within the range of 10-7-10-3 in both the summer and winter, which are below the theoretical risk threshold. For the carcinogenic risk, the LCR values ranged from 10-10 to 10-8, indicating no elevated carcinogenic risk due to TnBP, TCEP, and TDCP in indoor dust and air.


Assuntos
Poluição do Ar em Ambientes Fechados , Poeira , Exposição Ambiental , Monitoramento Ambiental , Retardadores de Chama , Organofosfatos , Estações do Ano , Retardadores de Chama/análise , China , Poeira/análise , Humanos , Medição de Risco , Universidades , Organofosfatos/análise , Poluição do Ar em Ambientes Fechados/análise , Poluição do Ar em Ambientes Fechados/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Exposição Ambiental/análise , Estudantes/estatística & dados numéricos , Poluentes Atmosféricos/análise
16.
ACS Nano ; 18(20): 13333-13345, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38717602

RESUMO

A persistent inflammatory response, intrinsic limitations in axonal regenerative capacity, and widespread presence of extrinsic axonal inhibitors impede the restoration of motor function after a spinal cord injury (SCI). A versatile treatment platform is urgently needed to address diverse clinical manifestations of SCI. Herein, we present a multifunctional nanoplatform with anisotropic bimodal mesopores for effective neural circuit reconstruction after SCI. The hierarchical nanoplatform features of a Janus structure consist of dual compartments of hydrophilic mesoporous silica (mSiO2) and hydrophobic periodic mesoporous organosilica (PMO), each possessing distinct pore sizes of 12 and 3 nm, respectively. Unlike traditional hierarchical mesoporous nanomaterials with dual-mesopores interlaced with each other, the two sets of mesopores in this Janus nanoplatform are spatially independent and possess completely distinct chemical properties. The Janus mesopores facilitate controllable codelivery of dual drugs with distinct properties: the hydrophilic macromolecular enoxaparin (ENO) and the hydrophobic small molecular paclitaxel (PTX). Anchoring with CeO2, the resulting mSiO2&PMO-CeO2-PTX&ENO nanoformulation not only effectively alleviates ROS-induced neuronal apoptosis but also enhances microtubule stability to promote intrinsic axonal regeneration and facilitates axonal extension by diminishing the inhibitory effect of extracellular chondroitin sulfate proteoglycans. We believe that this functional dual-mesoporous nanoplatform holds significant potential for combination therapy in treating severe multifaceted diseases.


Assuntos
Traumatismos da Medula Espinal , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/fisiopatologia , Animais , Porosidade , Dióxido de Silício/química , Paclitaxel/farmacologia , Paclitaxel/química , Anisotropia , Regeneração Nervosa/efeitos dos fármacos , Interações Hidrofóbicas e Hidrofílicas , Apoptose/efeitos dos fármacos , Ratos , Nanoestruturas/química , Camundongos , Tamanho da Partícula , Compostos de Organossilício/química , Compostos de Organossilício/farmacologia
17.
Environ Sci Technol ; 58(35): 15681-15690, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-38668375

RESUMO

Pharmaceutically active compounds are an important category of emerging pollutants, and their biological transformation processes in the environment are crucial for understanding and evaluating the migration, transformation, and environmental fate of emerging pollutants. The cytochrome P450 105 enzyme family has been proven to play an important role in the degradation of exogenous environmental pollutants. However, its thermostability and catalytic activity still need to be improved to better adapt to complex environmental conditions. This work elucidates the key mechanisms and important residues of the degradation reaction through multiple computational strategies, establishes a mutation library, and obtains 21 single-point mutation designs. Experimental verification showed that 16 single mutants had enhanced thermostability, with the R89F and L197Y mutants showing the highest increases in thermostability at 135 and 119% relative to the wild-type enzyme, respectively. Additionally, as a result of the higher specific activity of D390Q, it was selected for combination mutagenesis, ultimately resulting in three combination mutants (R89F/L197Y, R89F/D390Q, and R89F/L197Y/D390Q) with enhanced thermostability and catalytic activity. This study provides a modification approach for constructing efficient enzyme variants through semirational design and can contribute to the development of control technologies for emerging pollutants.


Assuntos
Sistema Enzimático do Citocromo P-450 , Diclofenaco , Sistema Enzimático do Citocromo P-450/metabolismo , Diclofenaco/química , Diclofenaco/metabolismo , Catálise
18.
Zhongguo Gu Shang ; 37(4): 374-80, 2024 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-38664208

RESUMO

OBJECTIVE: To analyze the correlation between hip joint musculoskeletal ultrasound score and ankylosing spondylitis (AS) disease activity, as well as to investigate the value of high frequency ultrasound in the assessment of hip joint involvement in AS. METHODS: The clinical data of 244 patients with AS who were treated in the rheumatology department of from March 2019 to March 2022 were retrospectively analyzed. Among them, there 174 males and 70 females, aged from 19 to 58 years old with an average of (34.22±9.49) years old;the disease duration of AS patients ranged from 8 months to 26 years, with an average of (13.68±4.04) years.The 244 patients were divided into disease group (83 cases) and control group (161 cases) based in the presence of hip joint involuement. According to the the disease activity, patients in the disease group were further categorezed into active phase (45 cases) and stable phase (38 cases). The ultrasound scores of patients in the active and stable phases of the disease group and the control group were compared. Relevant factors of hip joint involvement in AS patients were analyzed, and analyze the correlation between ultrasound score and Bath ankylosing spondylitis disease activity score index(BASDAI), Bath ankylosing spondylitis functional index(BASFI), visual analogue score of pain (VAS), C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and the correlation between hip joint capsule score and tendon attachment end score and BASDAI, BASFI, VAS, CRP and ESR. RESULTS: The hip joint capsule score(3.06±1.12), femoral head score(1.45±0.43), tendon attachment end score(3.28±1.30) and total ultrasound score(6.65±2.31) of the disease group were higher than those of the control group(1.51±0.48)、(0.66±0.27)、(1.61±0.53)、(3.81±1.44)scores (P<0.05). Multifactor Logstic regression analysis showed that the course of disease, hip joint capsule score and total ultrasound score were independent risk factors for hip involvement in AS patients.The hip capsule score (3.65±1.22)and total ultrasound score(8.28±2.33) in the active phase of the disease group were higher than those in the stable phase (2.48±1.04)、( 6.82±1.96)scores(P<0.05). The hip joint capsule score and total ultrasonic score of AS patients were positively correlated with BASDAI, BASFI, VAS, CRP, and ESR (P<0.05, P<0.01).The score of tendon attachment end was positively correlated with CRP (P<0.05). The score of joint capsule effusion in AS patients was positively correlated with BASDAI, BASFI and VAS (P<0.05, P<0.01). The synovial blood flow score was positively correlated with BASDAI, VAS, CRP and ESR (P<0.05, P<0.01). The synovial thickening score was positively correlated with BASDAI, BASFI, VAS, CRP and ESR (P<0.05, P<0.01). There was no correlation between the score of tendon attachment end and BASDAI, BASFI, VAS, CRP and ESR. CONCLUSION: There is a correlation between hip joint ultrasonic score of hip joint and clinical indexes in AS patients.Hip joint capsule score and total ultrasonic score were independent risk factors for hip involvement in AS patients. High frequency ultrasound exhibits clinical value in the diagnosis of hip joint involvement in AS patients.


Assuntos
Articulação do Quadril , Espondilite Anquilosante , Ultrassonografia , Humanos , Espondilite Anquilosante/diagnóstico por imagem , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Articulação do Quadril/diagnóstico por imagem , Adulto Jovem , Estudos Retrospectivos
19.
J Nanobiotechnology ; 22(1): 151, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38575943

RESUMO

BACKGROUND: As the lethal bone tumor, osteosarcoma often frequently occurs in children and adolescents with locally destructive and high metastasis. Distinctive kinds of nanoplatform with high therapeutical effect and precise diagnosis for osteosarcoma are urgently required. Multimodal optical imaging and programmed treatment, including synergistic photothermal-chemodynamic therapy (PTT-CDT) elicits immunogenetic cell death (ICD) is a promising strategy that possesses high bio-imaging sensitivity for accurate osteosarcoma delineating as well as appreciable therapeutic efficacy with ignorable side-effects. METHODS AND RESULTS: In this study, mesoporous Cu and Ce based oxide nanoplatform with Arg-Gly-Asp (RGD) anchoring is designed and successfully constructed. After loading with indocyanine green, this nanoplatform can be utilized for precisely targeting and efficaciously ablating against osteosarcoma via PTT boosted CDT and the closely following ICD stimulation both in vitro and in vivo. Besides, it provides off-peak fluorescence bio-imaging in the second window of near-infrared region (NIR II, 1000-1700 nm) and Magnetic resonance signal, serves as the dual-mode contrast agents for osteosarcoma tissue discrimination. CONCLUSION: Tumor targeted Cu&Ce based mesoporous nanoplatform permits efficient osteosarcoma suppression and dual-mode bio-imaging that opens new possibility for effectively diagnosing and inhibiting the clinical malignant osteosarcoma.


Assuntos
Neoplasias Ósseas , Nanopartículas , Neoplasias , Osteossarcoma , Criança , Humanos , Adolescente , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Osteossarcoma/diagnóstico por imagem , Osteossarcoma/terapia , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/tratamento farmacológico , Imunoterapia , Linhagem Celular Tumoral , Fototerapia
20.
J Environ Manage ; 357: 120730, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38574705

RESUMO

Volatile organic compounds (VOCs) significantly contribute to ozone pollution formation, and many VOCs are known to be harmful to human health. Plastic has become an indispensable material in various industries and daily use scenarios, yet the VOC emissions and associated health risks in the plastic manufacturing industry have received limited attention. In this study, we conducted sampling in three typical plastic manufacturing factories to analyze the emission characteristics of VOCs, ozone formation potential (OFP), and health risks for workers. Isopropanol was detected at relatively high concentrations in all three factories, with concentrations in organized emissions reaching 322.3 µg/m3, 344.8 µg/m3, and 22.6 µg/m3, respectively. Alkanes are the most emitted category of VOCs in plastic factories. However, alkenes and oxygenated volatile organic compounds (OVOCs) exhibit higher OFP. In organized emissions of different types of VOCs in the three factories, alkenes and OVOCs contributed 22.8%, 67%, and 37.8% to the OFP, respectively, highlighting the necessity of controlling them. The hazard index (HI) for all three factories was less than 1, indicating a low non-carcinogenic toxic risk; however, there is still a possibility of non-cancerous health risks in two of the factories, and a potential lifetime cancer risk in all of the three factories. For workers with job tenures exceeding 5 years, there may be potential health risks, hence wearing masks with protective capabilities is necessary. This study provides evidence for reducing VOC emissions and improving management measures to ensure the health protection of workers in the plastic manufacturing industry.


Assuntos
Poluentes Atmosféricos , Ozônio , Compostos Orgânicos Voláteis , Humanos , Poluentes Atmosféricos/análise , Compostos Orgânicos Voláteis/análise , Monitoramento Ambiental , Medição de Risco , Indústria Manufatureira , Alcenos , China
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