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1.
Eur Rev Med Pharmacol Sci ; 28(8): 3135-3143, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38708472

RESUMO

OBJECTIVE: Benzene is one of the major carcinogenic factors that can affect liver, kidneys, and lungs. Chronic inhalation of benzene vapor by petrol stations workers has been shown to have an impact on hematological parameters; thus, the present study aimed to investigate the effect of benzene exposure on petrol station workers. SUBJECTS AND METHODS: The study involved 99 participants, 50 of whom have been exposed to benzene and 49 of whom have not (control). A 5 ml blood sample in an ethylenediaminetetraacetic acid (EDTA) anticoagulant tube was collected from each subject, and a complete blood count test was used to test hematological parameters. RESULTS: The current study showed a significant decrease in red blood cells, packed cell volume, and hemoglobin in the exposed group compared to the control group. However, the amount of white blood cells was significantly increased (p < 0.0001) in the exposed group compared to the control group. Notably, there was no significant difference in platelet counts between the two groups. In terms of exposure time, subjects who have been exposed to benzene for more than a year and fewer than 10 years showed a significant decrease (p < 0.05) in RBCs indices and a significant increase (p < 0.0001) in WBCs compared to those in the control group CONCLUSIONS: Thus, the findings indicated that significant differences in hematological parameters were found in workers who were exposed to benzene compared to those who had not been exposed.


Assuntos
Benzeno , Exposição Ocupacional , Humanos , Exposição Ocupacional/efeitos adversos , Benzeno/toxicidade , Adulto , Masculino , Contagem de Células Sanguíneas , Hemoglobinas/análise , Hemoglobinas/metabolismo , Pessoa de Meia-Idade
2.
Environ Sci Technol ; 58(19): 8380-8392, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38691504

RESUMO

A comprehensive understanding of the full volatility spectrum of organic oxidation products from the benzene series precursors is important to quantify the air quality and climate effects of secondary organic aerosol (SOA) and new particle formation (NPF). However, current models fail to capture the full volatility spectrum due to the absence of important reaction pathways. Here, we develop a novel unified model framework, the integrated two-dimensional volatility basis set (I2D-VBS), to simulate the full volatility spectrum of products from benzene series precursors by simultaneously representing first-generational oxidation, multigenerational aging, autoxidation, dimerization, nitrate formation, etc. The model successfully reproduces the volatility and O/C distributions of oxygenated organic molecules (OOMs) as well as the concentrations and the O/C of SOA over wide-ranging experimental conditions. In typical urban environments, autoxidation and multigenerational oxidation are the two main pathways for the formation of OOMs and SOA with similar contributions, but autoxidation contributes more to low-volatility products. NOx can reduce about two-thirds of OOMs and SOA, and most of the extremely low-volatility products compared to clean conditions, by suppressing dimerization and autoxidation. The I2D-VBS facilitates a holistic understanding of full volatility product formation, which helps fill the large gap in the predictions of organic NPF, particle growth, and SOA formation.


Assuntos
Benzeno , Benzeno/química , Compostos Orgânicos/química , Oxirredução , Aerossóis , Volatilização , Poluentes Atmosféricos , Modelos Teóricos
3.
Biomed Environ Sci ; 37(4): 341-353, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38727157

RESUMO

Objective: Hydroquinone (HQ), one of the phenolic metabolites of benzene, is widely recognized as an important participant in benzene-induced hematotoxicity. However, there are few relevant proteomics in HQ-induced hematotoxicity and the mechanism hasn't been fully understood yet. Methods: In this study, we treated K562 cells with 40 µmol/L HQ for 72 h, examined and validated protein expression changes by Label-free proteomic analysis and Parallel reaction monitoring (PRM), and performed bioinformatics analysis to identify interaction networks. Results: One hundred and eighty-seven upregulated differentially expressed proteins (DEPs) and 279 downregulated DEPs were identified in HQ-exposed K562 cells, which were involved in neutrophil-mediated immunity, blood microparticle, and other GO terms, as well as the lysosome, metabolic, cell cycle, and cellular senescence-related pathways. Focusing on the 23 DEGs and 5 DEPs in erythroid differentiation-related pathways, we constructed the network of protein interactions and determined 6 DEPs (STAT1, STAT3, CASP3, KIT, STAT5B, and VEGFA) as main hub proteins with the most interactions, among which STATs made a central impact and may be potential biomarkers of HQ-induced hematotoxicity. Conclusion: Our work reinforced the use of proteomics and bioinformatic approaches to advance knowledge on molecular mechanisms of HQ-induced hematotoxicity at the protein level and provide a valuable basis for further clarification.


Assuntos
Benzeno , Hemolíticos , Proteoma , Proteoma/metabolismo , Proteômica , Benzeno/toxicidade , Células K562 , Humanos , Testes de Toxicidade/métodos , Hemolíticos/toxicidade
4.
CNS Neurosci Ther ; 30(4): e14718, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38615366

RESUMO

AIMS: Classification of spinal muscular atrophy (SMA) is associated with the clinical prognosis; however, objective classification markers are scarce. This study aimed to identify metabolic markers in the cerebrospinal fluid (CSF) of children with SMA types II and III. METHODS: CSF samples were collected from 40 patients with SMA (27 with type II and 13 with type III) and analyzed for metabolites. RESULTS: We identified 135 metabolites associated with SMA types II and III. These were associated with lysine degradation and arginine, proline, and tyrosine metabolism. We identified seven metabolites associated with the Hammersmith Functional Motor Scale: 4-chlorophenylacetic acid, adb-chminaca,(+/-)-, dodecyl benzenesulfonic acid, norethindrone acetate, 4-(undecan-5-yl) benzene-1-sulfonic acid, dihydromaleimide beta-d-glucoside, and cinobufagin. Potential typing biomarkers, N-cyclohexylformamide, cinobufagin, cotinine glucuronide, N-myristoyl arginine, 4-chlorophenylacetic acid, geranic acid, 4-(undecan-5-yl) benzene, and 7,8-diamino pelargonate, showed good predictive performance. Among these, N-myristoyl arginine was unaffected by the gene phenotype. CONCLUSION: This study identified metabolic markers are promising candidate prognostic factors for SMA. We also identified the metabolic pathways associated with the severity of SMA. These assessments can help predict the outcomes of screening SMA classification biomarkers.


Assuntos
Fenilacetatos , Atrofias Musculares Espinais da Infância , Criança , Humanos , Benzeno , Metabolômica , Arginina
5.
Environ Int ; 186: 108645, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38615541

RESUMO

Benzene is a broadly used industrial chemicals which causes various hematologic abnormalities in human. Altered DNA methylation has been proposed as epigenetic biomarkers in health risk evaluation of benzene exposure, yet the role of methylation at specific CpG sites in predicting hematological effects remains unclear. In this study, we recruited 120 low-level benzene-exposed and 101 control male workers from a petrochemical factory in Maoming City, Guangdong Province, China. Urinary S-phenylmercapturic acid (SPMA) in benzene-exposed workers was 3.40-fold higher than that in control workers (P < 0.001). Benzene-induced hematotoxicity was characterized by reduced white blood cells counts and nuclear division index (NDI), along with an increased DNA damage and urinary 8-hydroxy-2'-deoxyguanosine (all P < 0.05). Methylation levels of TRIM36, MGMT and RASSF1a genes in peripheral blood lymphocytes (PBLCs) were quantified by pyrosequencing. CpG site 6 of TRIM36, CpG site 2, 4, 6 of RASSF1a and CpG site 1, 3 of MGMT methylation were recognized as hot CpG sites due to a strong correlation with both internal exposure and hematological effects. Notably, integrating hot CpG sites methylation of multiple genes reveal a higher efficiency in prediction of integrative damage compared to individual genes at hot CpG sites. The negative dose-response relationship between the combined methylation of hot CpG sites in three genes and integrative damage enabled the classification of benzene-exposed individuals into high-risk or low-risk groups using the median cut-off value of the integrative index. Subsequently, a prediction model for integrative damage in benzene-exposed populations was built based on the methylation status of the identified hot CpG sites in the three genes. Taken together, these findings provide a novel insight into application prospect of specific CpG site methylation as epi-biomarkers for health risk assessment of environmental pollutants.


Assuntos
Acetilcisteína/análogos & derivados , Benzeno , Ilhas de CpG , Metilação de DNA , Exposição Ocupacional , Humanos , Metilação de DNA/efeitos dos fármacos , Masculino , Exposição Ocupacional/efeitos adversos , Benzeno/toxicidade , Adulto , China , Dano ao DNA , Pessoa de Meia-Idade , Biomarcadores/urina , Acetilcisteína/urina , Proteínas Supressoras de Tumor/genética , Enzimas Reparadoras do DNA/genética
6.
Ecotoxicol Environ Saf ; 276: 116302, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38608381

RESUMO

Benzene is a known contributor to human leukaemia through its toxic effects on bone marrow cells, and epigenetic modification is believed to be a potential mechanism underlying benzene pathogenesis. However, the specific roles of N6-methyladenosine (m6A), a newly discovered RNA post-transcriptional modification, in benzene-induced hematotoxicity remain unclear. In this study, we identified self-renewing malignant proliferating cells in the bone marrow of benzene-exposed mice through in vivo bone marrow transplantation experiments and Competitive Repopulation Assay. Subsequent analysis using whole transcriptome sequencing and RNA m6A methylation sequencing revealed a significant upregulation of RNA m6A modification levels in the benzene-exposed group. Moreover, RNA methyltransferase METTL14, known as a pivotal player in m6A modification, was found to be aberrantly overexpressed in Lin-Sca-1+c-Kit+ (LSK) cells of benzene-exposed mice. Further analysis based on the GEO database showed a positive correlation between the expression of METTL14, mTOR, and GFI and benzene exposure dose. In vitro cellular experiments, employing experiments such as western blot, q-PCR, m6A RIP, and CLIP, validated the regulatory role of METTL14 on mTOR and GFI1. Mechanistically, continuous damage inflicted by benzene exposure on bone marrow cells led to the overexpression of METTL14 in LSK cells, which, in turn, increased m6A modification on the target genes' (mTOR and GFI1) RNA. This upregulation of target gene expression activated signalling pathways such as mTOR-AKT, ultimately resulting in malignant proliferation of bone marrow cells. In conclusion, this study offers insights into potential early targets for benzene-induced haematologic malignant diseases and provides novel perspectives for more targeted preventive and therapeutic strategies.


Assuntos
Adenosina/análogos & derivados , Benzeno , Metiltransferases , Benzeno/toxicidade , Animais , Metiltransferases/genética , Metiltransferases/metabolismo , Camundongos , Transformação Celular Neoplásica/induzido quimicamente , Transformação Celular Neoplásica/genética , Células Mieloides/efeitos dos fármacos , Células Mieloides/patologia , Camundongos Endogâmicos C57BL , Serina-Treonina Quinases TOR/metabolismo , Serina-Treonina Quinases TOR/genética , Masculino
7.
Int J Mol Sci ; 25(7)2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38612886

RESUMO

Stimuli-responsive supramolecular polymers are ordered nanosized materials that are held together by non-covalent interactions (hydrogen-bonding, metal-ligand coordination, π-stacking and, host-guest interactions) and can reversibly undergo self-assembly. Their non-covalent nature endows supramolecular polymers with the ability to respond to external stimuli (temperature, light, ultrasound, electric/magnetic field) or environmental changes (temperature, pH, redox potential, enzyme activity), making them attractive candidates for a variety of biomedical applications. To date, supramolecular research has largely evolved in the development of smart water-soluble self-assemblies with the aim of mimicking the biological function of natural supramolecular systems. Indeed, there is a wide variety of synthetic biomaterials formulated with responsiveness to control and trigger, or not to trigger, aqueous self-assembly. The design of responsive supramolecular polymers ranges from the use of hydrophobic cores (i.e., benzene-1,3,5-tricarboxamide) to the introduction of macrocyclic hosts (i.e., cyclodextrins). In this review, we summarize the most relevant advances achieved in the design of stimuli-responsive supramolecular systems used to control transport and release of both diagnosis agents and therapeutic drugs in order to prevent, diagnose, and treat human diseases.


Assuntos
Ciclodextrinas , Polímeros Responsivos a Estímulos , Humanos , Benzeno , Materiais Biocompatíveis , Eletricidade , Água
8.
ACS Sens ; 9(4): 1906-1915, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38565844

RESUMO

As a carcinogenic and highly neurotoxic hazardous gas, benzene vapor is particularly difficult to be distinguished in BTEX (benzene, toluene, ethylbenzene, xylene) atmosphere and be detected in low concentrations due to its chemical inertness. Herein, we develop a depth-related pore structure in Cu-TCPP-Cu to thermodynamically and kinetically enhance the adsorption of benzene vapor and realize the detection of ultralow-temperature benzene gas. We find that the in-plane π electronic nature and proper pore sizes in Cu-TCPP-Cu can selectively induce the adsorption and diffusion of BTEX. Interestingly, the theoretical calculations (including density functional theory (DFT) and grand canonical Monte Carlo (GCMC) simulations) exhibit that benzene molecules are preferred to adsorb and array as a consecutive arrangement mode in the Cu-TCPP-Cu pore, while the TEX (toluene, ethylbenzene, xylene) dominate the jumping arrangement model. The differences in distribution behaviors can allow adsorption and diffusion of more benzene molecules within limited room. Furthermore, the optimal pore-depth range (60-65 nm) of Cu-TCPP-Cu allows more exposure of active sites and hinders the gas-blocking process. The optimized sensor exhibits ultrahigh sensitivity to benzene vapor (155 Hz/µg@1 ppm), fast response time (less than 10 s), extremely low limit of detection (65 ppb), and excellent selectivity (83%). Our research thus provides a fundamental understanding to design and optimize two-dimensional metal-organic framework (MOF)-based gas sensors.


Assuntos
Benzeno , Cobre , Limite de Detecção , Estruturas Metalorgânicas , Termodinâmica , Benzeno/análise , Benzeno/química , Cobre/química , Estruturas Metalorgânicas/química , Adsorção , Cinética , Teoria da Densidade Funcional , Gases/análise , Gases/química
9.
J Environ Sci (China) ; 143: 201-212, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38644017

RESUMO

Silver (9 wt.%) was loaded on Co3O4-nanofiber using reduction and impregnation methods, respectively. Due to the stronger electronegativity of silver, the ratios of surface Co3+/Co2+ on Ag/Co3O4 were higher than on Co3O4, which further led to more adsorbed oxygen species as a result of the charge compensation. Moreover, the introducing of silver also obviously improved the reducibility of Co3O4. Hence the Ag/Co3O4 showed better catalytic performance than Co3O4 in benzene oxidation. Compared with the Ag/Co3O4 synthesized via impregnation method, the one prepared using reduction method (named as AgCo-R) exhibited higher contents of surface Co3+ and adsorbed oxygen species, stronger reducibility, as well as more active surface lattice oxygen species. Consequently, AgCo-R showed lowest T90 value of 183°C, admirable catalytic stability, largest normalized reaction rate of 1.36 × 10-4 mol/(h·m2) (150°C), and lowest apparent activation energy (Ea) of 63.2 kJ/mol. The analyzing of in-situ DRIFTS indicated benzene molecules were successively oxidized to phenol, o-benzoquinone, small molecular intermediates, and finally to CO2 and water on the surface of AgCo-R. At last, potential reaction pathways including five detailed steps were proposed.


Assuntos
Benzeno , Cobalto , Oxirredução , Óxidos , Prata , Benzeno/química , Cobalto/química , Prata/química , Catálise , Óxidos/química , Modelos Químicos , Poluentes Atmosféricos/química
10.
Toxicol Ind Health ; 40(6): 337-351, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38597775

RESUMO

Gasoline station attendants are exposed to numerous chemicals that might have genotoxic and carcinogenic potential, such as benzene in fuel vapor and particulate matter and polycyclic aromatic hydrocarbons in vehicle exhaust emission. According to IARC, benzene and diesel particulates are Group 1 human carcinogens, and gasoline has been classified as Group 2A "possibly carcinogenic to humans." At gas stations, self-service is not implemented in Turkey; fuel-filling service is provided entirely by employees, and therefore they are exposed to those chemicals in the workplace during all working hours. Genetic monitoring of workers with occupational exposure to possible genotoxic agents allows early detection of cancer. We aimed to investigate the genotoxic damage due to exposures in gasoline station attendants in Turkey. Genotoxicity was evaluated by the Comet, chromosomal aberration, and cytokinesis-block micronucleus assays in peripheral blood lymphocytes. Gasoline station attendants (n = 53) had higher tail length, tail intensity, and tail moment values than controls (n = 61). In gasoline station attendants (n = 46), the frequencies of chromatid gaps, chromosome gaps, and total aberrations were higher compared with controls (n = 59). Increased frequencies of micronuclei and nucleoplasmic bridges were determined in gasoline station attendants (n = 47) compared with controls (n = 40). Factors such as age, duration of working, and smoking did not have any significant impact on genotoxic endpoints. Only exposure increased genotoxic damage in gasoline station attendants independently from demographic and clinical characteristics. Occupational exposure-related genotoxicity risk may increase in gasoline station attendants who are chronically exposed to gasoline and various chemicals in vehicle exhaust emissions.


Assuntos
Aberrações Cromossômicas , Dano ao DNA , Gasolina , Testes para Micronúcleos , Exposição Ocupacional , Humanos , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/análise , Gasolina/toxicidade , Adulto , Masculino , Turquia , Aberrações Cromossômicas/induzido quimicamente , Dano ao DNA/efeitos dos fármacos , Pessoa de Meia-Idade , Poluentes Ocupacionais do Ar/análise , Poluentes Ocupacionais do Ar/toxicidade , Ensaio Cometa , Biomarcadores , Emissões de Veículos/toxicidade , Emissões de Veículos/análise , Linfócitos/efeitos dos fármacos , Feminino , Mutagênicos/toxicidade , Benzeno/toxicidade , Benzeno/análise
11.
J Occup Environ Hyg ; 21(5): 353-364, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38560919

RESUMO

Structural firefighters are exposed to a complex set of contaminants and combustion byproducts, including volatile organic compounds (VOCs). Additionally, recent studies have found structural firefighters' skin may be exposed to multiple chemical compounds via permeation or penetration of chemical byproducts through or around personal protective equipment (PPE). This mannequin-based study evaluated the effectiveness of four different PPE conditions with varying contamination control measures (incorporating PPE interface design features and particulate blocking materials) to protect against ingress of several VOCs in a smoke exposure chamber. We also investigated the effectiveness of long-sleeve base layer clothing to provide additional protection against skin contamination. Outside gear air concentrations were measured from within the smoke exposure chamber at the breathing zone, abdomen, and thigh heights. Personal air concentrations were collected from mannequins under PPE at the same general heights and under the base layer at abdomen and thigh heights. Sampled contaminants included benzene, toluene, styrene, and naphthalene. Results suggest that VOCs can readily penetrate the ensembles. Workplace protection factors (WPFs) were near one for benzene and toluene and increased with increasing molecular weight of the contaminants. WPFs were generally lower under hoods and jackets compared to under pants. For all PPE conditions, the pants appeared to provide the greatest overall protection against ingress of VOCs, but this may be due in part to the lower air concentrations toward the floor (and cuffs of pants) relative to the thigh-height outside gear concentrations used in calculating the WPFs. Providing added interface control measures and adding particulate-blocking materials appeared to provide a protective benefit against less-volatile chemicals, like naphthalene and styrene.


Assuntos
Poluentes Ocupacionais do Ar , Bombeiros , Naftalenos , Exposição Ocupacional , Roupa de Proteção , Compostos Orgânicos Voláteis , Compostos Orgânicos Voláteis/análise , Exposição Ocupacional/prevenção & controle , Exposição Ocupacional/análise , Poluentes Ocupacionais do Ar/análise , Humanos , Benzeno/análise , Tolueno/análise , Equipamento de Proteção Individual , Estireno/análise , Manequins , Fumaça/análise , Local de Trabalho
12.
Bioresour Technol ; 400: 130650, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38570099

RESUMO

Illustrating the biodegradation processes of multi-component volatile organic compounds (VOCs) will expedite the implication of biotechnology in purifying industrial exhaust. Here, performance shifts of microbial fuel cell and biotrickling filter combined system (MFC-BTF) are investigated for removing single and dual components of toluene and benzene. Synchronous removal of toluene (95 %) and benzene (97 %) are achieved by MFC-BTF accompanied with the output current of 0.41 mA. Elevated content of extracellular polymeric substance facilitates the mass transfer of benzene with the presence of toluene. Strains of Bacteroidota, Proteobacteria and Chloroflexi contribute to the removal of dual components VOCs. Empty bed reaction time and the VOCs concentration are the important factors influencing their dissolution in the system. The biodegradation of toluene and benzene proceeds with 2-hydroxymuconic semialdehyde and o-hydroxybenzoic acid as the main intermediates. These results provide a comprehensive understanding of multi-component VOCs removal by MFC-BTF and guide the system design, optimization, and scale-up.


Assuntos
Benzeno , Biodegradação Ambiental , Fontes de Energia Bioelétrica , Tolueno , Tolueno/metabolismo , Benzeno/metabolismo , Filtração/métodos , Compostos Orgânicos Voláteis/metabolismo , Gases/metabolismo
13.
Front Public Health ; 12: 1295758, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38590813

RESUMO

Introduction: In Nigeria, because of increasing population, urbanization, industrialization, and auto-mobilization, petrol is the most everyday non-edible commodity, and it is the leading petroleum product traded at the proliferating Nigeria's petrol stations (NPSs). However, because of inadequate occupational health and safety (OHS) regulatory measures, working at NPSs exposes petrol station workers (PSWs) to a large amount of hazardous benzene, toluene, ethylbenzene, and xylene (BTEX) compounds. Methods: Studies on BTEX exposures among Nigerian PSWs are scarce. Thus, constraints in quantifying the health risks of BTEX limit stakeholders' ability to design practical risk assessment and risk control strategies. This paper reviews studies on the OHS of Nigerian PSWs at the NPSs. Results: Although knowledge, attitude, and practices on OHS in NPSs vary from one Nigeria's study setting to another, generally, safety practices, awareness about hazards and personal protective equipment (PPE), and the use of PPE among PSWs fell below expectations. Additionally, air quality at NPSs was poor, with a high content of BTEX and levels of carbon monoxide, hydrogen sulfide, particulate matter, and formaldehyde higher than the World Health Organization guideline limits. Discussion: Currently, regulatory bodies' effectiveness and accountability in safeguarding OHS at NPSs leave much to be desired. Understanding the OHS of NPSs would inform future initiatives, policies, and regulations that would promote the health and safety of workers at NPSs. However, further studies need to be conducted to describe the vulnerability of PSWs and other Nigerians who are occupationally exposed to BTEX pollution. More importantly, controlling air pollution from hazardous air pollutants like BTEX is an essential component of OHS and integral to attaining the Sustainable Development Goals (SDG) 3, 7, and 11.


Assuntos
Derivados de Benzeno , Benzeno , Exposição Ocupacional , População da África Ocidental , Humanos , Benzeno/análise , Xilenos/análise , Tolueno/análise , Nigéria , Exposição Ocupacional/análise , Monitoramento Ambiental
14.
Environ Sci Pollut Res Int ; 31(19): 27935-27948, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38523212

RESUMO

Herein, microwave-assisted activated carbon (MW-AC) was fabricated from peanut shells using a ZnCl2 activator and utilized for the first time to eliminate benzene vapor as a volatile organic compound (VOC). During the MW-AC production process, which involved two steps-microwave treatment and muffle furnace heating-we investigated the effects of various factors and achieved the highest iodine number of 1250 mg/g. This was achieved under optimal operating conditions, which included a 100% impregnation ratio, CO2 as the gas in the microwave environment, a microwave power set at 500 W, a microwave duration of 10 min, an activation temperature of 500 °C and an activation time of 45 min. The structural and morphological properties of the optimized MW-AC were assessed through SEM, FTIR, and BET analysis. The dynamic adsorption process of benzene on the optimized MW-AC adsorbent, which has a significant BET surface area of 1204.90 m2/g, was designed using the Box-Behnken approach within the response surface methodology. Under optimal experimental conditions, including a contact duration of 80 min, an inlet concentration of 18 ppm, and a temperature of 26 °C, the maximum adsorption capacity reached was 568.34 mg/g. The experimental data are better described by the pseudo-second-order kinetic model, while it is concluded that the equilibrium data are better described by the Langmuir isotherm model. MW-AC exhibited a reuse efficiency of 86.54% for benzene vapor after five consecutive recycling processes. The motivation of the study highlights the high adsorption capacity and superior reuse efficiency of MW-AC adsorbent with high BET surface area against benzene pollutant. According to our results, the developed MW-AC presents itself as a promising adsorbent candidate for the treatment of VOCs in various industrial applications.


Assuntos
Arachis , Benzeno , Carvão Vegetal , Micro-Ondas , Compostos de Zinco , Adsorção , Benzeno/química , Carvão Vegetal/química , Compostos de Zinco/química , Arachis/química , Compostos Orgânicos Voláteis/química , Cloretos/química , Cinética , Poluentes Atmosféricos/química
15.
Bioorg Med Chem ; 102: 117652, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38442523

RESUMO

Aromatic rings are critical core substructures in the majority of pharmaceutical compounds. There is much recent interest in replacing aromatic structures with saturated bioisosteres of benzene, which are generally fused or bridged ring systems. These bioisosteres often show improved solubility properties compared to benzene, and may also undergo fewer unwanted metabolic processes. One key reason why aromatic rings have proven so successful in drug design is their rigidity. This paper uses molecular dynamics simulations supported by crystallographic data to assess the rigidity of bicyclopentane and cubane ring systems as two of the most common benzene bioisosteres and compares this to benzene. Whilst a benzene ring is shown to be more flexible than these two bioisosteres in terms of its dihedral ring flexibility, substituents around the ring tend to behave in a much more similar way in both benzene and the bioisosteric systems.


Assuntos
Benzeno , Pentanos , Benzeno/química , Simulação de Dinâmica Molecular , Solubilidade
16.
Org Lett ; 26(11): 2212-2217, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38452132

RESUMO

In this report, we present a photopromoted, metal-free transannulation of phenyl azides for the synthesis of DNA-encoded seven-membered rings. The transformation is efficiently achieved through a skeletal editing strategy targeting the benzene motif coupled with a Reversible Adsorption to Solid Support (RASS) strategy. A variety of valuable DNA-encoded seven-membered ring compounds, including DNA-encoded 3H-azepines, azepinones, and unnatural amino acids, are now accessible. Crucially, this DNA-compatible protocol can also be applied for the introduction of complex molecules, as exemplified by Lorcaserin and Betahistine. The selective conversion of readily available phenyl rings into high-value seven-membered rings offers a promising avenue for the construction of diversified and drug-like DNA-encoded library.


Assuntos
Azidas , Benzeno , Ciclização , Aminas , DNA
17.
J Environ Sci (China) ; 142: 155-168, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38527881

RESUMO

We conducted a simultaneous field study of PM2.5-bound particulate polycyclic aromatic hydrocarbons (PAHs) and aromatic acids (AAs) in a polluted city Zhengzhou to explore the concentration, sources and potential conversion pathways between PAHs and AAs in different seasons. The average concentrations of PM2.5, 28PAHs and 8AAs during the sampling period were 77 µg/m3, 75 ng/m3, and 283 ng/m3, respectively. The concentration of both 28PAHs and 8AAs were highest in winter and lowest in summer with ratios of 6.3 and 2.3, respectively. PAHs with 5-7 rings were the main components of PAHs (52%), followed by 4 rings PAHs (30%) and 2-3 rings PAHs (18%). According to the source appointment results obtained by positive matrix factorization, the main sources of PAHs were combustion and vehicle emissions, which account for 37% and 34%, respectively. 8AAs were divided into three groups, including four benzene dicarboxylic acids (B2CAs), three benzene tricarboxylic acids (B3CAs) and one benzene tetracarboxylic acid (B4CA). And interspecies correlation analysis with PM2.5 source markers were used to investigate potential sources. Phthalic acid (o-Ph) was the most abundant specie of 8AAs (157 ng/m3, 55% of 8AAs), which was well correlated with sulfate. Meanwhile, B3CAs and B4CA were highly correlated with sulfate and weakly correlated with levoglucosan, suggesting that secondary formation was their main source. As logical oxidation products of PAHs, o-Ph and B3CAs showed good correlations with a number of PAHs, indicating possible photochemical oxidation pathway by PAHs. In addition, O3, NO2, temperature and relative humidity have positive effects on the secondary formation of B3CAs.


Assuntos
Poluentes Atmosféricos , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Atmosféricos/análise , Material Particulado/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Benzeno , Monitoramento Ambiental/métodos , China , Emissões de Veículos/análise , Estações do Ano , Poeira/análise , Carvão Mineral/análise , Sulfatos/análise
18.
Sci Rep ; 14(1): 7219, 2024 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-38538743

RESUMO

Petroleum aromatic hydrocarbons are considered one of the most dangerous aquatic pollutants due to their widespread across water bodies, persistence, and extension to the food chain. To our knowledge, there hasn't been any research investigating the hepatorenoprotective effects of Spirulina platensis (SP) against toxicity induced by these environmental toxicants in fish. Thus, we decided to explore its potential safeguarding against benzene and toluene exposure in adult Clarias gariepinus. To achieve this objective, fish were divided into five groups (60 per group; 20 per replicate). The first group served as a control. The second and third groups were intoxicated with benzene and toluene at doses of 0.762 and 26.614 ng/L, respectively for 15 days. The fourth and fifth groups (SP + benzene and SP + toluene, respectively) were challenged with benzene and toluene as previously mentioned following dietary inclusion of SP at a dose of 5 g/kg diet for 30 days. The marked increase in liver metabolizing enzymes, glucose, total protein, albumin, globulin, albumin/globulin ratio, and creatinine confirmed the hepato- and nephrotoxic impacts of benzene and toluene. These outcomes were coupled with cytopathological affections and excessive collagen deposition. The incorporation of SP in ration formulation, on the contrary, restored the previously mentioned toxicological profile due to its antioxidant and cytoprotective attributes. Regardless of SP intervention, the renal tissues still displayed histo-architectural lesions, because of insufficient dose and timeframe. Additional research will be required to identify the ideal SP remediation regimen.


Assuntos
Peixes-Gato , Globulinas , Spirulina , Animais , Benzeno/metabolismo , Peixes-Gato/metabolismo , Globulinas/metabolismo , Tolueno/metabolismo , Albuminas/metabolismo
19.
Ann Agric Environ Med ; 31(1): 13-23, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38549472

RESUMO

INTRODUCTION AND OBJECTIVE: Smog, which contains fine dusts, non-metal oxides, metals and organic compounds can have irritating, allergenic and immunomodulatory effects leading to the development of respiratory diseases and their exacerbations. The aim of the study was to search for a relationship between concentrations of air pollutants and the frequency of hospitalizations due to exacerbation of asthma, chronic obstructive pulmonary disease, or abnormalitis in breathing. MATERIAL AND METHODS: Hospital admission data was accessed from the hospital digital in-formation system. From the publicly available database of the Chief Inspectorate for Environmental Protection, data concerning the concentrations of pollutants, such as PM2.5 and PM10, sulphur oxide IV (SO2), nitric oxide IV (NO2), carbon monoxide II (CO), benzene and ozone (O3), measured daily with hourly accuracy was used. The results of the average concentrations of air pollutants were compared with the rates of hospitalization in the corresponding time intervals. RESULTS: A number of statistically significant correlations were shown indicating the role of increased concentrations of each of the tested contaminants in the frequency of hospitalizations. In particular, strongly positive correlations were shown between the frequency of hospitalizations due to COPD and PM2.5 and PM10, asthma with benzene and NO2, and for respiratory disorders in general with benzene, CO and SO2. CONCLUSIONS: The results indicate that air pollution can be a significant modifiable risk factor for exacerbations of respiratory diseases and therefore its avoidance plays an important role in primary prevention.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Asma , Doença Pulmonar Obstrutiva Crônica , Doenças Respiratórias , Humanos , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Dióxido de Nitrogênio , Benzeno , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Hospitalização , Asma/epidemiologia , Asma/etiologia , Material Particulado/efeitos adversos , Material Particulado/análise
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