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1.
Biomolecules ; 14(3)2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38540694

RESUMO

Parkinson's disease (PD) is a neurodegenerative disorder characterized by the loss of dopaminergic neurons responsible for unintended or uncontrollable movements. Mutations in the leucine-rich repeat kinase 2 locus contribute to genetic forms of PD. The fruit fly Drosophila melanogaster carrying this mutation (LRRK2-Dm) is an in vivo model of PD that develops motor impairment and stands for an eligible non-mammalian paradigm to test novel therapeutic approaches. Dehydrozingerone (DHZ) is a natural phenolic compound isolated from ginger and presents anti-inflammatory, antioxidant and neuroprotective properties, making it a potential therapeutic target for PD. We administered DHZ and its C2-symmetric dimer (DHZ-DIM) at 0.5 and 1 mM for 14 and 21 days in the LRRK2-Dm, with the aim of assessing changes in rescuing motor behavior, brain dopaminergic neurons, mitochondria and synapses (T-bars). The shorter treatment with both molecules revealed efficacy at the higher dose, improving climbing behavior with a prevention of dopaminergic neuronal demise. After 21 days, a recovery of the motor disability, dopaminergic neuron loss, mitochondrial damage and T-bars failure was observed with the DHZ-DIM. Our data indicate that the DHZ-DIM exerts a more potent neuroprotective effect with respect to the monomer in LRRK2-Dm, prompting further investigation of these compounds in rodent models of PD.


Assuntos
Pessoas com Deficiência , Transtornos Motores , Fármacos Neuroprotetores , Doença de Parkinson , Estirenos , Animais , Humanos , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/genética , Drosophila , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Drosophila melanogaster/genética , Neurônios Dopaminérgicos , Suplementos Nutricionais , Mutação
2.
J Emerg Med ; 66(4): e463-e466, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38461133

RESUMO

BACKGROUND: Modern resin hemoadsorption/hemoperfusion for calcium channel blocker overdose is yet to be reported. The characteristics of calcium channel blockers make them unamenable to removal by hemodiafiltration or charcoal hemoperfusion; however, elimination, using styrene bead adsorption in an ex vivo model, has been demonstrated. Its clinical use is described. CASE REPORT: A man in his 20s was admitted with shock into the Intensive Care Unit (ICU) after an overdose of amlodipine and risperidone. Resuscitation and supportive care were administered, but hypotension did not resolve despite the administration of intravenous fluids, infusions of calcium, adrenaline, and hyperinsulinemic-euglycemic therapy. Methylene blue was then administered to maintain the mean arterial pressures. However, the hemodynamic effect did not allow the weaning of the adrenaline. Drug clearance using hemoadsorption/hemoperfusion was attempted using a styrene resin filter (Jafron HA230; Jafron Biomedical Co., Ltd., Guangdong, China). During the two hemoperfusion sessions (6 h duration each, and 18 h apart) the patient had successfully weaned off all supportive measures, with lactate levels returning to normal and was later discharged home. At the end of each session, significant amlodipine concentrations were detected in blood aspirated from both filters, suggesting enhanced clearance. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Our case illustrates a temporal relationship between resin hemoperfusion therapy, resolution of hemodynamic instability, and shock without proving causation. Significant amlodipine elimination was suggested by high concentrations found in blood from the filter. At the same time, shock resolution after initiation of hemoperfusion occurred in less than one elimination half-life of amlodipine.


Assuntos
Overdose de Drogas , Choque , Masculino , Humanos , Bloqueadores dos Canais de Cálcio/uso terapêutico , Resultado do Tratamento , Anlodipino/uso terapêutico , Choque/etiologia , Choque/terapia , Overdose de Drogas/terapia , Epinefrina , Estirenos
3.
Sci Total Environ ; 918: 170734, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38325455

RESUMO

Daycare centers (DCCs) play an instrumental role in early childhood development, making them a significant indoor environment for a large number of children globally. Amidst routine DCC activities, young children are exposed to a myriad of volatile organic compounds (VOCs), potentially impacting their health. Therefore, this study aims to investigate the VOC emissions during typical DCCs activities and evaluate respective health risk assessments. Employing a full-scale experimental setup within a well-controlled climate chamber, research was conducted into VOC emissions during three typical DCC events: arts-and-crafts (painting, gluing, modeling), cleaning, and sleeping activities tied to mattresses. The research identified 96 distinct VOCs, grouped into twelve categories, from 20 different events examined. Each event exhibited a unique VOC fingerprint, pinpointing potential source tracers. Also, significant variations in VOC emissions from different events were demonstrated. For instance, under cool & dry conditions, acrylic painting recorded high total VOC concentrations of 808 µg/m3, whereas poster painting showed only 58 µg/m3. Given these disparities, the study emphasizes the critical need for carefully selecting arts-and-crafts materials and cleaning agents in DCCs to effectively reduce VOC exposure. It suggests ventilating new mattresses before use and regular mattress check-ups to mitigate VOCs exposure during naps. Importantly, it revealed that certain events resulted in VOC levels exceeding the 10-5 cancer risk thresholds for younger children. Specifically, tetrachloroethylene and styrene from used mattresses in cool & dry conditions, ethylene oxide from new mattresses in warm & humid conditions, and styrene, during sand modeling in both conditions, were the key compounds contributing to this risk. These findings highlight the critical need for age-specific health risk assessments in DCCs. This study highlights the significance of understanding the profiles of VOC emissions from indoor events in DCCs, emphasizing potential health implications and laying a solid foundation for future investigations in this field.


Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Compostos Orgânicos Voláteis , Pré-Escolar , Criança , Humanos , Compostos Orgânicos Voláteis/análise , Medição de Risco , Clima , Estirenos , Poluição do Ar em Ambientes Fechados/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental
4.
J Agric Food Chem ; 72(8): 4334-4338, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38354400

RESUMO

4-Vinylanisole is an aggregation pheromone of the locust. Both gregarious and solitary locusts exhibit a strong attraction toward 4-vinylanisole, irrespective of gender or age. Therefore, 4-vinylanisole can be used for trapping and monitoring locusts. In this study, the construction of a de novo 4-vinylanisole pathway in Escherichia coli has been demonstrated for the first time. Subsequently, by increasing the supply of precursor substrates, we further improved the biosynthesis of 4-vinylanisole. Finally, a two-phase organic overlay culture was used to increase the titer to 206 mg/L. It presents a sustainable and ecofriendly alternative for the synthesis of 4-vinylanisole.


Assuntos
Escherichia coli , Gafanhotos , Animais , Escherichia coli/genética , Escherichia coli/metabolismo , Estirenos , Feromônios/metabolismo , Engenharia Metabólica
5.
Clin Interv Aging ; 19: 109-118, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38250175

RESUMO

Purpose: To explore the predictive value of nutritional risk for all-cause death and functional outcomes among elderly acute stroke patients. Patients and Methods: A total of 479 elderly acute stroke patients were enrolled in this study. The nutritional risk of patients was screened by the GNRI and NRS-2002. The primary outcome was all-cause death, and the secondary outcome was poor prognosis defined as a modified Rankin Scale (mRS) score ≥3. Results: Based on the NRS-2002, patients with nutritional risk had a higher risk of all-cause death at 3 months (adjusted OR: 3.642, 95% CI 1.046~12.689) and at 3 years (adjusted OR: 2.266, 95% CI 1.259~4.076) and a higher risk of adverse functional outcomes at 3 months (adjusted OR: 2.748, 95% CI 1.518~4.972. Based on the GNRI, compared to those without nutritional risk, patients with mild malnutrition also had a higher risk of all-cause death at 3 months (adjusted OR: 7.186, 95% CI 1.550~33.315) and at 3 years (adjusted OR: 2.255, 95% CI 1.211~4.199) and a higher risk of adverse functional outcomes at 3 months (adjusted OR: 1.947, 95% CI 1.030~3.680), so patients with moderate and severe malnutrition had a higher risk of all-cause death at 3 months (adjusted OR: 6.535, 95% CI 1.380~30.945) and at 3 years (adjusted OR: 2.498, 95% CI 1.301~4.799) and a higher risk of adverse functional outcomes at 3 months (adjusted OR: 2.213, 95% CI 1.144~4.279). Conclusion: Nutritional risk increases the risk of poor short-term and long-term outcomes in elderly patients with acute stroke. For elderly stroke patients, we should pay attention to early nutritional risk screening, and effective intervention should be provided to improve the prognosis of such patients.


Assuntos
Desnutrição , Pirimidinas , Acidente Vascular Cerebral , Estirenos , Tiofenos , Idoso , Humanos , Seguimentos , China
6.
Biosens Bioelectron ; 249: 116015, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38211464

RESUMO

Highly efficient luminescent materials play an important role in electrochemiluminescence (ECL) biosensing systems. Herein, the poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) modified carbon dots (CDs)/zeolitic imidazolate framework-8 (ZIF-8) compositing metal-organic frameworks (MOFs) materials with excellent luminescence performance were prepared as the ECL emitters for biosensing application. In this novel ternary composites, CDs were used as emitters, ZIF-8 was used as a carrier, and the luminescent performance was finally improved by introducing PEDOT:PSS to improve the conductivity of the nanomaterials. As a result, CDs/PEDOT:PSS/ZIF-8 exhibited an approximately 8 times ECL intensity compared to CDs alone. By further modifying with AuNPs, the enhancement factor reached ≈10 in reference to the individual CDs. After combining with a DNAzyme-based two-cycle target amplification principle, an ECL biosensor was constructed to achieve high-sensitivity detection of miRNA-21 with a detection limit of 50 aM. The biosensor also demonstrated desirable selectivity, excellent stability, and quantitative ability for human serum target detection. Overall, these findings not only provide a promising pathway for high luminous efficiency ECL emitters synthesis, but also provide a platform for ultrasensitive miRNA sensing.


Assuntos
Técnicas Biossensoriais , Compostos Bicíclicos Heterocíclicos com Pontes , Nanopartículas Metálicas , Estruturas Metalorgânicas , MicroRNAs , Polímeros , Pontos Quânticos , Humanos , MicroRNAs/genética , Carbono , Ouro , Medições Luminescentes , Técnicas Eletroquímicas , Estirenos , Limite de Detecção
7.
ACS Appl Mater Interfaces ; 16(5): 5613-5626, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38278772

RESUMO

In vivo, cells reside in a 3D porous and dynamic microenvironment. It provides biochemical and biophysical cues that regulate cell behavior in physiological and pathological processes. In the context of fundamental cell biology research, tissue engineering, and cell-based drug screening systems, a challenge is to develop relevant in vitro models that could integrate the dynamic properties of the cell microenvironment. Taking advantage of the promising high internal phase emulsion templating, we here designed a polyHIPE scaffold with a wide interconnected porosity and functionalized its internal 3D surface with a thin layer of electroactive conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) to turn it into a 4D electroresponsive scaffold. The resulting scaffold was cytocompatible with fibroblasts, supported cellular infiltration, and hosted cells, which display a 3D spreading morphology. It demonstrated robust actuation in ion- and protein-rich complex culture media, and its electroresponsiveness was not altered by fibroblast colonization. Thanks to customized electrochemical stimulation setups, the electromechanical response of the polyHIPE/PEDOT scaffolds was characterized in situ under a confocal microscope and showed 10% reversible volume variations. Finally, the setups were used to monitor in real time and in situ fibroblasts cultured into the polyHIPE/PEDOT scaffold during several cycles of electromechanical stimuli. Thus, we demonstrated the proof of concept of this tunable scaffold as a tool for future 4D cell culture and mechanobiology studies.


Assuntos
Polímeros , Estirenos , Tecidos Suporte , Tecidos Suporte/química , Porosidade , Polímeros/farmacologia , Polímeros/química , Técnicas de Cultura de Células , Engenharia Tecidual/métodos
8.
Angew Chem Int Ed Engl ; 63(13): e202317860, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38280216

RESUMO

Single component flavin-dependent halogenases (FDHs) possess both flavin reductase and FDH activity in a single enzyme. We recently reported that the single component FDH AetF catalyzes site-selective bromination and iodination of a variety of aromatic substrates and enantioselective bromolactonization and iodoetherification of styrenes bearing pendant carboxylic acid or alcohol substituents. Given this inherent reactivity and selectivity, we explored the utility of AetF as catalyst for alkene and alkyne C-H halogenation. We find that AetF catalyzes halogenation of a range of 1,1-disubstituted styrenes, often with high stereoselectivity. Despite the utility of haloalkenes for cross-coupling and other applications, accessing these compounds in a stereoselective manner typically requires functional group interconversion processes, and selective halogenation of 1,1'-disubstituted olefins remains rare. We also establish that AetF and homologues of this enzyme can halogenate terminal alkynes. Mutagenesis studies and deuterium kinetic isotope effects are used to support a mechanistic proposal involving covalent catalysis for halogenation of unactivated alkynes by AetF homologues. These findings expand the scope of FDH catalysis and continue to show the unique utility of single component FDHs for biocatalysis.


Assuntos
Alcenos , Halogenação , Alcenos/química , Alcinos , Flavinas/química , Estirenos
9.
Artif Organs ; 48(2): 117-129, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37909148

RESUMO

BACKGROUND: Functionalization of wound dressing is one of the main approaches for promoting wound healing in skin wound management. In this study, our aim is to fabricate a bio-functionalized hydrocolloid wound dressing. METHODS: The extracellular matrix (ECM) was extracted from human placental tissue. A hydrocolloid film was fabricated using Na-CMC, pectin, gelatin, styrene-isoprene-styrene adhesive, glycerol, and 0.5%-2.5% powdered ECM. A polyurethane film and a release liner were used in the hydrocolloid/ECM films. The mechanical, adhesion, swelling rate, and integrity of the films were investigated. Cell proliferation, adhesion, and migration assays, as well as, SEM and FTIR spectroscopy were also conducted. Macroscopic and microscopic evaluations of wound healing process and formation of blood vessels were conducted in mouse animal models. RESULTS: We successfully fabricated a three-layered ECM-functionalized hydrocolloid dressing with a water vapor transmission rate of 371 g/m2 /day and an adhesion peel strength of 176 KPa. Cellular adhesion, proliferation and migration were promoted by ECM. In the animal tests, ECM-functionalized hydrocolloids significantly improved wound closure and re-epithelialization at days 14 and 21. Also, ECM-functionalized hydrocolloids promoted the formation of hair follicles. CONCLUSIONS: Our findings suggest that ECM could enhance the wound healing properties of hydrocolloid wound dressings. This wound dressing could be considered for application in hard-to-heal acute wounds.


Assuntos
Matriz Extracelular , Placenta , Gravidez , Humanos , Feminino , Camundongos , Animais , Curativos Hidrocoloides , Animais de Laboratório , Coloides/química , Estirenos
10.
Chemosphere ; 349: 140811, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38040248

RESUMO

Alkene ozonolysis can produce stabilized Criegee intermediates (SCIs), which play a key role in oligomers' formation. Though styrene and isoprene coexist in the ambient atmosphere as important anthropogenic and biogenic secondary organic aerosol (SOA) precursors, respectively, their cross-reactions have not received attention. This study investigated the interactions of SCIs from styrene and isoprene ozonolysis for the first time. The high-resolution Orbitrap mass spectrometer was used to determine the unique ion mass spectra of the isoprene-styrene-O3 mixture. The results show that the signal intensities of new ions account for >8.4% of total ions in the mass spectra of the styrene-isoprene-O3 mixed system. Styrene and isoprene ozonolysis can produce characteristic C7-SCI and C4-SCI, respectively. C7-SCI and C4-SCI can be involved in the cross-reactions, and the results of tandem mass spectra directly confirmed both C7-SCI and C4-SCI as chain units. The O/C and H/C ratios of cross-products are in the range of 0.38-1.07 and 1.00-1.50, respectively, which are consistent with cross-reaction products. Adding a C7-SCI unit reduces the oligomer's volatility by 1.3-1.4 orders of magnitude lower than adding a C4-SCI unit. Thus, C4-SCI can compete with C7-SCI to react with styrene-derived RO2/RC(O)OH to produce more volatile cross-products, while the less volatile cross-products can be formed when isoprene-derived RO2/RC(O)OH reacted with C7-SCI instead of C4-SCI. The SOA yield of the mixed system is lower than that of the single styrene-O3 system but higher than that of the single isoprene-O3 system. Ambient particles were also collected, and 5 possible SCI-related cross-products were identified. This study illustrates the effects of SCI-related cross-reactions on SOA components and physicochemical properties, providing a basis for future research on SCI-related cross-reactions that frequently occur in the ambient atmosphere.


Assuntos
Poluentes Atmosféricos , Ozônio , Poluentes Atmosféricos/química , Ozônio/química , Íons , Estirenos , Aerossóis/química
11.
J Thorac Cardiovasc Surg ; 167(3): 1166-1176.e2, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37558202

RESUMO

OBJECTIVE: Volatile organic compounds (VOCs) are used in the sterilization and manufacture of medical equipment. These compounds have high vapor pressures with low water solubility and are emitted as gases from solids or liquids. They can be mutagenic, neurotoxic, genotoxic, and/or carcinogenic. Safe limits of exposure are not known for neonates. This study examined determinants of exposure in newborns undergoing cardiac surgery. METHODS: Twenty metabolites of 16 VOCs (eg, xylene, cyanide, acrolein, acrylonitrile, N, N-dimethylformamide, 1,3-butadiene, styrene, and benzene) were measured as metabolites in daily urine samples collected from 10 neonates undergoing cardiac operations (n = 150 samples). Metabolites were quantified using reversed-phase ultra-high performance liquid chromatography and electrospray ionization tandem mass spectrometry. Repeated measures analysis of covariance was performed for each metabolite to examine associations with use of medical devices. RESULTS: At least 3 metabolites were detected in every sample. The median number of metabolites detected in each sample was 14 (range, 3-15). In a model controlling for other factors, the use of extracorporeal membrane oxygenation was associated with significantly (P ≤ .05) greater metabolite levels of acrolein, acrylonitrile, ethylene oxide, propylene oxide, styrene, and ethylbenzene. Patients breathing ambient air had greater levels of metabolites of acrolein, xylene, N,N-dimethylformamide, methyl isocyanate, cyanide, 1,3-butadiene (all P ≤ .05). CONCLUSIONS: Exposure to volatile organic compounds is pervasive in newborns undergoing cardiac surgery. Sources of exposure likely include medical devices and inhalation from the air in the intensive care unit. The contribution of VOC exposure during cardiac surgery in newborns to adverse outcomes warrants further evaluation.


Assuntos
Acrilonitrila , Poluentes Atmosféricos , Butadienos , Procedimentos Cirúrgicos Cardíacos , Compostos Orgânicos Voláteis , Humanos , Recém-Nascido , Compostos Orgânicos Voláteis/análise , Poluentes Atmosféricos/urina , Acroleína/análise , Xilenos/análise , Acrilonitrila/análise , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Cianetos/análise , Estirenos/análise
12.
Chemosphere ; 350: 140980, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38141678

RESUMO

Indoor volatile organic compounds (VOCs) are usually sampled using active carbon samplers and subsequently analyzed using gas chromatography-mass spectrometry (GC-MS) to assess the exposure risk to workers. Therefore, selection of a suitable solvent for VOC extraction is crucial. However, reports on the use of 2-phenoxyethanol-known for its low vapor pressure and low toxicity-as a solvent for extracting VOCs from activated carbon are lacking. Here, we show that 2-phenoxyethanol is a suitable alternative solvent with low toxicity and can extract a wide variety of VOCs without overlapping with target VOCs on the gas chromatogram. The recoveries of 2-phenoxyethanol were 57% (styrene) to 83% (methyl n-butyl ketone), which were higher than those of CS2, acetone, and n-hexane at room temperature. The recoveries improved to 67% (styrene) to 102% (isopentyl acetate) under 50 °C. Optimization of the GC conditions showed that a viscosity delay time of 3 s was required to avoid producing bubbles in the injection syringes. We selected DB-HeavyWAX as a column because it could be heated above the boiling point of 2-phenoxyethanol (247 °C), allowing the removal of 2-phenoxyethanol from the column. This study contributes to the development of analysis methods for VOCs under safe operating conditions.


Assuntos
Compostos Orgânicos Voláteis , Humanos , Compostos Orgânicos Voláteis/análise , Solventes , Etilenoglicóis , Carvão Vegetal , Estirenos
13.
Molecules ; 28(23)2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38067608

RESUMO

Volatile organic compounds (VOCs) and flavor characteristics of Rosa roxburghii Tratt. (RR) and Rosa sterilis (RS) were analyzed using headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry (HS-SPME-GC-MS). The flavor network was constructed by combining relative odor activity values (ROAVs), and the signature differential flavor components were screened using orthogonal partial least squares discriminant analysis (OPLS-DA) and random forest (RF). The results showed that 61 VOCs were detected in both RR and RS: 48 in RR, and 26 in RS. There were six key flavor components (ROAVs ≥ 1) in RR, namely nonanal, ethyl butanoate, ethyl hexanoate, (3Z)-3-hexen-1-yl acetate, ethyl caprylate, and styrene, among which ethyl butanoate had the highest contribution, whereas there were eight key flavor components (ROAVs ≥ 1) in RS, namely 2-nonanol, (E)-2-hexenal, nonanal, methyl salicylate, ß-ocimene, caryophyllene, α-ionone, and styrene, among which nonanal contributed the most to RS. The flavor of RR is primarily fruity, sweet, green banana, and waxy, while the flavor of RS is primarily sweet and floral. In addition, OPLS-DA and RF suggested that (E)-2-hexenal, ethyl caprylate, ß-ocimene, and ethyl butanoate could be the signature differential flavor components for distinguishing between RR and RS. In this study, the differences in VOCs between RR and RS were analyzed to provide a basis for further development and utilization.


Assuntos
Rosa , Compostos Orgânicos Voláteis , Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Sólida/métodos , Odorantes/análise , Compostos Orgânicos Voláteis/análise , Estirenos
14.
Int J Mol Sci ; 24(23)2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38069247

RESUMO

Pheromone-binding proteins (PBPs) play important roles in binding and transporting sex pheromones. However, the PBP genes identified in coleopteran insects and their information sensing mechanism are largely unknown. Cyrtotrachelus buqueti (Coleoptera: Curculionidae) is a major insect pest of bamboo plantations. In this study, a novel PBP gene, CbuqPBP2, from C. buqueti was functionally characterized. CbuqPBP2 was more abundantly expressed in the antennae of both sexes than other body parts, and its expression level was significantly male-biased. Fluorescence competitive binding assays showed that CbuqPBP2 exhibited the strongest binding affinity to dibutyl phthalate (Ki = 6.32 µM), followed by styrene (Ki = 11.37 µM), among twelve C. buqueti volatiles. CbuqPBP2, on the other hand, showed high binding affinity to linalool (Ki = 10.55), the main volatile of host plant Neosinocalamus affinis. Furthermore, molecular docking also demonstrated the strong binding ability of CbuqPBP2 to dibutyl phthalate, styrene, and linalool, with binding energy values of -5.7, -6.6, and -6.0 kcal/mol, respectively, and hydrophobic interactions were the prevailing forces. The knockdown of CbuqPBP2 expression via RNA interference significantly reduced the electroantennography (EAG) responses of male adults to dibutyl phthalate and styrene. In conclusion, these results will be conducive to understanding the olfactory mechanisms of C. buqueti and promoting the development of novel strategies for controlling this insect pest.


Assuntos
Besouros , Mariposas , Receptores Odorantes , Gorgulhos , Feminino , Animais , Masculino , Proteínas de Transporte/metabolismo , Besouros/metabolismo , Gorgulhos/genética , Gorgulhos/metabolismo , Feromônios/metabolismo , Dibutilftalato , Simulação de Acoplamento Molecular , Estirenos/metabolismo , Proteínas de Insetos/metabolismo , Mariposas/genética , Receptores Odorantes/genética , Receptores Odorantes/metabolismo , Ligação Proteica
15.
J Mech Behav Biomed Mater ; 148: 106193, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37918337

RESUMO

This work presents a structural computational simulation of a polymeric aortic valve prosthesis, made with a hyperelastic material (Styrene-Ethylene/Propylene-Styrene). The valve has a suture ring, three pillars placed at 120° and three leaflets. The analysis is based on a modification over previous designs consisting in a fillet concave surface to avoid stress concentration at the junctions between leaflets and pillars. Three shapes were simulated. The first one was used to validate the computational method by comparison of the results with a recent paper. The second shape was designed to show that a fillet or "rounding" can be beneficial to the stress leaflet reduction. The third shape was also designed to show that the reduction of leaflet thickness and intercommissural distance between leaflets at the pillar junctions improves the valve opening and closure. The use of fillet with a 0.5 mm radius, reduced 26.5% the maximum Von Mises stresses for the second shape and 33.9% for the third shape. Additionally, for the latter, the opening area was not affected for the high stiffness due to fillet. The results -mainly for the third shape-are promising and give rise to future studies: further shape optimization, analysis for other materials and valve simulation under pathological loads.


Assuntos
Valva Aórtica , Próteses Valvulares Cardíacas , Desenho de Prótese , Análise de Elementos Finitos , Modelos Cardiovasculares , Simulação por Computador , Polímeros , Estirenos , Estresse Mecânico
16.
Chemosphere ; 344: 140371, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37820874

RESUMO

Unsaturated polyester resins (UPR) are composed of prepolymers and styrene diluents, while the former are produced by co-polycondensation between diol, unsaturated diacid and saturated diacid. In this work, bio-based UPR prepolymers were synthesized from bio-based oxalic acid, itaconic acid, and ethylene glycol, which were then diluted with bio-based isosorbide methacrylate (MI). Meanwhile, the phenylphosphonate were introduced into the molecular chains of prepolymers to achieve intrinsic flame retardancy of bio-based UPR. The potential of the reactive MI diluents as substitutes of volatile styrene, was also assessed through the volatility test, curing kinetics and gel contents analysis. For UPR materials with styrene diluents, the UPR materials can achieve UL-94 V0 level and the 28% of limiting oxygen index (LOI) with 2.63 wt% of phosphorus contents. By contrast, the UPR materials with MI diluents can reach UL-94 V0 level with only 2.14 wt% of phosphorus contents. As the phosphorus contents were further increased to 2.63 wt%, UPR materials can achieve highest 29%, while the peak of heat release rate (PHRR) and total heat release (THR) were decreased by 68.01% and 48.62%, respectively. The Flame Retardancy Index (FRI) was also used to comprehensively evaluate the flame retardant performance of UPR composites. Compared with neat UPR, the composites with MI diluents and phosphorus containing structures increased from 1.00 to 6.46. The mechanism for improved flame retardancy was analyzed from gaseous and condensed phase. Additionally, the tensile strengths of bio-based UPR materials with styrene and MI diluents were studied. This work provides an effective method to prepared high-performance and fully bio-based UPR materials with improved flame retardant properties and safety application of reactive diluents.


Assuntos
Retardadores de Chama , Poliésteres , Excipientes , Isossorbida , Ácido Oxálico , Fósforo , Estirenos
17.
Blood Purif ; 52(11-12): 880-887, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37857261

RESUMO

INTRODUCTION: Hemoadsorption has emerged as an adjunctive therapy for sepsis, but its impact on antibiotic levels remains poorly defined. We conducted an in vivo experimental study to investigate the removal of vancomycin and gentamicin during hemoadsorption using the HA380 cartridge, a novel styrene-divinylbenzene copolymer cartridge. METHODS: Six surgically prepared sheep were administered 2 g of vancomycin and 400 mg of gentamicin over 30 min, followed by a continuous infusion of vancomycin (20 mg/h). Hemoadsorption was implemented with a styrene-divinylbenzene copolymer HA380 cartridge at a blood flow of 120 mL/min. The removal ratio, sorbent-based clearance, and the mass removal rate were calculated for each time point. RESULTS: The mean 10-min vancomycin removal ratio exceeded 90% and declined to 68.0% at 30 min; 52.8% at 60 min, and 28.0% by 4 h. Due to constant plasma flow, clearance varied proportionally with the removal ratio. Over 4 hours, the total mass removal was 556 mg (SD 106.3). For gentamicin, the mean 10-min removal ratio was 96.9% and the final ratio at 4 h remained 53.0%, with clearances changing proportionately. The total mass removal of gentamicin was 138 mg (SD 26.6) over 4 h. The sorbent-based clearance of vancomycin was significantly lower than that of gentamicin (Pgroup < 0.0001). CONCLUSION: The novel HA380 sorbent cartridge appears safe and achieves significant vancomycin and gentamicin removal over a four-hour period. This information can be used by clinicians to guide their prescription and consider the additional dosing of at least an extra 25-35% amount in patients receiving HA380 hemoadsorption therapy during sepsis.


Assuntos
Sepse , Vancomicina , Humanos , Animais , Ovinos , Gentamicinas , Antibacterianos , Sepse/terapia , Estirenos
18.
Proc Natl Acad Sci U S A ; 120(37): e2306659120, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37669362

RESUMO

Chemical signals from conspecifics are essential in insect group formation and maintenance. Migratory locusts use the aggregation pheromone 4-vinylanisole (4VA), specifically released by gregarious locusts, to attract and recruit conspecific individuals, leading to the formation of large-scale swarms. However, how 4VA contributes to the transition from solitary phase to gregarious phase remains unclear. We investigated the occurrence of locust behavioral phase changes in the presence and absence of 4VA perception. The findings indicated that solitary locusts require crowding for 48 and 72 h to adopt partial and analogous gregarious behavior. However, exposure to increased concentrations of 4VA enabled solitary locusts to display behavioral changes within 24 h of crowding. Crowded solitary locusts with RNAi knockdown of Or35, the specific olfactory receptor for 4VA, failed to exhibit gregarious behaviors. Conversely, the knockdown of Or35 in gregarious locusts resulted in the appearance of solitary behavior. Additionally, a multi-individual behavioral assay system was developed to evaluate the interactions among locust individuals, and four behavioral parameters representing the inclination and conduct of social interactions were positively correlated with the process of crowding. Our data indicated that exposure to 4VA accelerated the behavioral transition from solitary phase to gregarious phase by enhancing the propensity toward proximity and body contact among conspecific individuals. These results highlight the crucial roles of 4VA in the behavioral phase transition of locusts. Furthermore, this study offers valuable insights into the mechanisms of behavioral plasticity that promote the formation of locust swarms and suggests the potential for 4VA application in locust control.


Assuntos
Gafanhotos , Gafanhotos/fisiologia , Comunicação Animal , Comportamento Animal , Receptores Odorantes/metabolismo , Estirenos/metabolismo
19.
Int J Biol Macromol ; 253(Pt 4): 127068, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37758105

RESUMO

The aim of this study was to develop a lightweight epoxy based biocomposite for morphing wing and unmanned aerial vehicle (UAV) applications. The proposed composite was developed using a 3D printed high stiffness lignin-Acrylonitrile Butadiene Styrene (ABS) core and industrial hemp with aluminized glass fiber epoxy skin. The ABS was reinforced using lignin macromolecule derived from cashew nut shells via twin screw extruder and the core was printed using an industrial grade 3D printer. Furthermore, the composites were prepared by compression moulding with an ABS-lignin core and hemp/aluminized GF surface and characterized according to respective American society of testing and materials (ASTM) standards. The findings indicate that the addition of 30 vol% Al-glass and hemp fiber with lignin strengthened ABS core improved the mechanical properties. The composite material designated as "E2" exhibits the maximum mechanical properties, providing tensile strength, flexural strength, Izod impact, interlaminar shear strength (ILSS), and compression values of, 136 MPa, 168 MPa, 4.82 kJ/m2, 21 MPa, and 155 MPa respectively. The maximal energy absorbed by composite designation "E2," during drop load impact test is 20.6 J. Similarly, the composite designation "E2"gives fatigue life cycles of 33,709, 25,781 and 19,633 for 50 %, 70 % and 90 % of ultimate tensile strength (UTS) and 32.5 (K1c) MPa⋅m and 0.76 (G1c) MJ/m2 in fracture toughness and energy release rate respectively.


Assuntos
Acrilonitrila , Anacardium , Cannabis , Animais , Butadienos , Lignina , Nozes , Dispositivos Aéreos não Tripulados , Resinas Epóxi , Impressão Tridimensional , Estirenos
20.
Chemosphere ; 339: 139753, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37553041

RESUMO

Evidence on liver injury and non-alcoholic fatty liver disease (NAFLD) from volatile organic compounds (VOCs) exposure is insufficient. A cross-sectional study including 3011 US adults from the National Health and Nutrition Examination Survey was conducted to explore the associations of urinary exposure biomarkers (EBs) for 13 VOCs (toluene, xylene, ethylbenzene, styrene, acrylamide, N,N-dimethylformamide, acrolein, crotonaldehyde, 1,3-butadiene, acrylonitrile, cyanide, propylene oxide, and 1-bromopropane) with liver injury biomarkers and the risk of NAFLD by performing single-chemical (survey weight regression) and mixture (Bayesian kernel machine regression [BKMR] and weighted quantile sum [WQS]) analyses. We found significant positive associations of EBs for toluene and 1-bromopropane with alanine aminotransferase (ALT), EBs for toluene, crotonaldehyde, and 1,3-butadiene with asparate aminotransferase (AST), EBs for 1,3-butadiene and cyanide with alkaline phosphatase (ALP), EBs for xylene and cyanide with hepamet fibrosis score (HFS), EBs for the total 13 VOCs (except propylene oxide) with United States fatty liver index (USFLI), and EBs for xylene, N,N-dimethylformamide, acrolein, crotonaldehyde, and acrylonitrile with NALFD; and significant inverse associations of EBs for ethylbenzene, styrene, acrylamide, acrolein, crotonaldehyde, 1,3-butadiene, acrylonitrile, cyanide, and propylene oxide with total bilirubin, EBs for ethylbenzene, styrene, acrylamide, acrolein, 1,3-butadiene, acrylonitrile, and cyanide with albumin (ALB), EBs for ethylbenzene, styrene, acrylamide, N,N-dimethylformamide, acrolein, crotonaldehyde, 1,3-butadiene, acrylonitrile, cyanide, and propylene oxide with total protein (TP), and EB for 1-bromopropane with AST/ALT (all P-FDR<0.05). In BKMR and WQS, the mixture of VOC-EBs was significantly positively associated with ALT, AST, ALP, HFS, USFLI, and the risk of NAFLD, while significantly inversely associated with TBIL, ALB, TP, and AST/ALT. VOCs exposure was associated with liver injury and increased risk of NAFLD in US adults. These findings highlight that great attention should be paid to the potential risk of liver health damage from VOCs exposure.


Assuntos
Acrilonitrila , Hepatopatia Gordurosa não Alcoólica , Compostos Orgânicos Voláteis , Humanos , Adulto , Estados Unidos/epidemiologia , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Compostos Orgânicos Voláteis/análise , Xilenos/análise , Inquéritos Nutricionais , Acroleína , Acrilonitrila/toxicidade , Teorema de Bayes , Estudos Transversais , Dimetilformamida , Tolueno/análise , Biomarcadores , Acrilamidas , Estirenos/análise
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