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1.
Int J Biol Macromol ; 269(Pt 2): 132145, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38723819

RESUMO

Sulfonated lignin-based dye dispersants have intensively attracted attention due to their low cost, renewability and abundant sources. However, their utilization is limited by the low content of sulfonic groups and high content of hydroxyl groups in their complex lignin structure, which results in various problems such as high reducing rate of dye, severe staining of the fibers and uneven dyeing. Here, the multi-site sulfonated lignin-based dispersants were prepared with high sulfonic group content (2.20 mmol/g) and low hydroxyl content (2.43 mmol/g). When using it as the dispersant, the dye uptake rate was improved from 69.23 % to 98.55 %, the reducing rate was decreased from 20.82 % to 2.03 %, the K/S value was reduced from 0.69 to 0.02, and the particle sizes in dye system before and after high temperature treatment were stabilized below 0.5 µm. Besides, the dispersion effect was significantly improved because no obvious separation between dye and water was observed even if without the assistance of grinding process. In short, the multi-site sulfonation method proposed in this work could remarkably improve the performances of the lignin-based dye dispersants, which would facilitate the development of the dye dispersion and the high value utilization of lignin.

2.
J Hazard Mater ; 472: 134498, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38733782

RESUMO

Advanced oxidation processes for the treatment of organic pollutants in wastewater suffer from difficulties in mineralization, potential risks of dissolved residues, and high oxidant consumption. In this study, radical-initiated polymerization is dominated in an UV/peroxydisulfate (PDS) process to eliminate organic pollutant of pharmaceutical metoprolol (MTP). Compared with an ideal degradation-based UV/PDS process, the present process can save four fifths of PDS consumption at the same dissolved organic carbon removal of 47.3%. Simultaneously, organic carbon can be recovered from aqueous solution by separating solid polymers at a ratio of 50% of the initial chemical oxygen demand. The chemical structure of products was analyzed to infer the transformation pathways of MTP. Unlike previous studies on simple organic pollutants that the polymerization can occur independently, the polymerization of MTP is dependent on the partial degradation of MTP, and the main monomer in polymerization is a dominant degradation product (4-(2-methoxyethyl)-phenol, denoted as DP151). The separated solid polymers are formed by repeated oxidation and coupling of DP151 or its derivatives through a series of intermediate oligomers. This proof-of-concept study demonstrates the advantage of polymerization-dominated mechanism on dealing with large organic molecules with complex structures, as well as the potential of UV/PDS process for simultaneous organic pollution reduction and organic carbon recovery from aqueous solution.

3.
J Hazard Mater ; 471: 134363, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38663291

RESUMO

Degradation of organics in high-salinity wastewater is beneficial to meeting the requirement of zero liquid discharge for coking wastewater treatment. Creating efficient and stable performance catalysts for high-salinity wastewater treatment is vital in catalytic ozonation process. Compared with ozonation alone, Mn and Ce co-doped γ-Al2O3 could remarkably enhance activities of catalytic ozonation for chemical oxygen demand (COD) removal (38.9%) of brine derived from a two-stage reverse osmosis treatment. Experimental and theoretical calculation results indicate that introducing Mn could increase the active points of catalyst surface, and introducing Ce could optimize d-band electronic structures and promote the electron transport capacity, enhancing HO• bound to the catalyst surface ([HO•]ads) generation. [HO•]ads plays key roles for degrading the intermediates and transfer them into low molecular weight organics, and further decrease COD, molecular weights and number of organics in reverse osmosis concentrate. Under the same reaction conditions, the presence of Mn/γ-Al2O3 catalyst can reduce ΔO3/ΔCOD by at least 37.6% compared to ozonation alone. Furthermore, Mn-Ce/γ-Al2O3 catalytic ozonation can reduce the ΔO3/ΔCOD from 2.6 of Mn/γ-Al2O3 catalytic ozonation to 0.9 in the case of achieving similar COD removal. Catalytic ozonation has the potential to treat reverse osmosis concentrate derived from bio-treated coking wastewater reclamation.

4.
Langmuir ; 40(18): 9741-9750, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38652825

RESUMO

Capillary flow has garnered significant attention due to its unique dynamic characteristics that require no external force. Creating a quantitative analytical model to evaluate capillary flow behaviors in root-like networks is essential for enhancing fluid control properties in functional textiles. In this study, we explore the capillary dynamics within root-like networks under the influence of gravity and derive the most rapid capillary flow via structural optimization. The flow time in a capillary is dominated by the capillary pressure, viscous pressure loss, and gravity, each of which exhibits diverse sensitivities to the structures of root-like networks. We scrutinize various structural parameters to understand their impact on capillary flow in root-like networks. Subsequently, optimal structural parameters (namely, the mother tube diameter and diameter ratio) are identified to minimize capillary flow time. Moreover, we discovered that the correlation between flow time and distance for capillary flow in root-like networks does not obey the classical Lucas-Washburn equation. These results affirm that root-like networks can enhance capillary flow, providing critical insights for numerous capillary-flow-dependent engineering applications.

5.
Int J Biol Macromol ; 267(Pt 2): 131610, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38621565

RESUMO

Brain-derived neurotrophic factor (BDNF) is a neurotrophic protein that promotes neuronal survival, increases neurotransmitter synthesis, and has potential therapeutic effects in neurodegenerative and psychiatric diseases, but its drug development has been limited by the fact that recombinant proteins of BDNF are unstable and do not penetrate the blood-brain barrier (BBB). In this study, we fused a TAT membrane-penetrating peptide with BDNF to express a recombinant protein (TBDNF), which was then PEG-modified to P-TBDNF. Protein characterization showed that P-TBDNF significantly improved the stability of the recombinant protein and possessed the ability to penetrate the BBB, and in cellular experiments, P-TBDNF prevented MPTP-induced nerve cell oxidative stress damage, apoptosis and inflammatory response, and its mechanism of action was closely related to the activation of tyrosine kinase B (TrkB) receptor and inhibition of microglia activation. In animal experiments, P-TBDNF improved motor and cognitive deficits in MPTP mice and inhibited pathological changes in Parkinson's disease (PD). In conclusion, this paper is expected to reveal the mechanism of action of P-TBDNF in inhibiting neurotoxicity, provide a new way for treating PD, and lay the foundation for the future development of recombinant P-TBDNF.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Fármacos Neuroprotetores , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/farmacologia , Fator Neurotrófico Derivado do Encéfalo/genética , Camundongos , Fármacos Neuroprotetores/farmacologia , Proteínas Recombinantes/farmacologia , Barreira Hematoencefálica/metabolismo , Masculino , Estresse Oxidativo/efeitos dos fármacos , Humanos , Apoptose/efeitos dos fármacos , Receptor trkB/metabolismo , Neurônios/metabolismo , Neurônios/efeitos dos fármacos , Doença de Parkinson/metabolismo , Doença de Parkinson/tratamento farmacológico , Camundongos Endogâmicos C57BL
6.
Chemosphere ; 357: 142043, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38626810

RESUMO

Emerging pollutants are toxic and harmful chemical substances characterized by environmental persistence, bioaccumulation and biotoxicity, which can harm the ecological environment and even threaten human health. There are four categories of emerging pollutants that are causing widespread concern, namely, persistent organic pollutants, endocrine disruptors, antibiotics, and microplastics. The distribution of emerging pollutants has spatial and temporal heterogeneity, which is influenced by factors such as geographical location, climatic conditions, population density, emission amount, etc. Steroidal estrogens (SEs) discussed in this paper belong to the category of endocrine disruptors. There are generally three types of fate for SEs in the soil environment: sorption, degradation and humification. Humification is a promising pathway for the removal of SEs, especially for those that are difficult to degrade. Through humification, these difficult-to-degrade SEs can be effectively transferred or fixed, thus reducing their impact on the environment and organisms. Contrary to the well-studied process of sorption and degradation, the role and promise of the humification process for the removal of SEs has been underestimated. Based on the existing research, this paper reviews the sources, classification, properties, hazards and environmental behaviors of SEs in soil, and focuses on the degradation and humification processes of SEs and the environmental factors affecting their processes, such as temperature, pH, etc. It aims to provide references for the follow-up research of SEs, and advocates further research on the humification of organic pollutants in future studies.


Assuntos
Disruptores Endócrinos , Estrogênios , Poluentes do Solo , Solo , Estrogênios/química , Estrogênios/análise , Poluentes do Solo/análise , Poluentes do Solo/química , Disruptores Endócrinos/química , Disruptores Endócrinos/análise , Solo/química , Substâncias Húmicas/análise , Biodegradação Ambiental , Poluentes Orgânicos Persistentes/química , Monitoramento Ambiental
7.
Front Mol Neurosci ; 17: 1379726, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38638604

RESUMO

Netrin-1 was initially discovered as a neuronal growth cue for axonal guidance, and its functions have later been identified in inflammation, tumorigenesis, neurodegeneration, and other disorders. We have recently found its alterations in the brains with Alzheimer's disease, which might provide important clues to the mechanisms of some unique pathologies. To provide better understanding of this promising molecule, we here summarize research progresses in genetics, pathology, biochemistry, cell biology and other studies of Netrin-1 about its mechanistic roles and biomarker potentials with an emphasis on clinical neurodegenerative disorders in order to expand understanding of this promising molecular player in human diseases.

8.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 55(2): 397-402, 2024 Mar 20.
Artigo em Chinês | MEDLINE | ID: mdl-38645847

RESUMO

Objective: To examine the characteristics of the prevalence of congenital cleft lip with/without cleft palate in the ethnic Tibetan population and to provide support for the precise prevention and treatment of cleft lip with/without cleft palate in the Tibetan population. Methods: The clinical data of Tibetan patients with cleft lip with/without cleft palate were collected and the clinical characteristics of the patients were analyzed. The patients' age ranged from 2 months to 51 years old. All the subjects were admitted to West China Stomatology Hospital, Sichuan University for the treatment of cleft lip with/without cleft palate between January 2016 and August 2023. Most of the subjects came from Sichuan Province and the Tibet Autonomous Region. Results: A total of 1051 patients were enrolled and children aged under 12 months (460 cases) accounted for the largest proportion. Among the subjects, 383 had cleft lip only (36.44%), 140 had cleft palate only (13.32%), and 528 had cleft lip with cleft palate (50.24%). The male-to-female ratios of patients with cleft lip only (0.99∶1), cleft palate only (0.54∶1), and cleft lip with cleft palate (1.67∶1) exhibited significant differences (P<0.001). However, there was no significant difference in the male-to-female ratio in patients with cleft lip only or those with cleft lip with cleft palate when the subjects were divided into two groups according to whether they had unilateral or bilateral cleft lip with/without cleft palate. Most of the patients with bilateral cleft lip were female, while most of the patients with unilateral cleft lip and unilateral or bilateral cleft lip with cleft palate were male. The unilateral cleft lip with/without cleft palate was located predominantly on the left side. Syndromic cleft lip with/without cleft palate accounted for 3.43% of all the cases and the most common concomitant deformity was congenital heart disease. 3.81% (40 cases) of the patients had a family history. In the patients with cleft lip only and those with cleft palate only, the proportion of patients having parents with corresponding phenotypes was higher than those of other phenotypes of cleft lip with/without cleft palate. Regarding the birth time distribution of the children with cleft lip with/without cleft palate, Spring saw the highest number of births of these children (311 cases, 29.59%), while Winter saw the lowest number of births (231 cases, 21.98%). Conclusion: The cases of cleft lip with/without cleft palate in the ethnic Tibetan population are predominantly cleft lip and palate. Unilateral cleft lip only or cleft lip with palate is predominantly located on the left side. Lip disease phenotypes may be more heritable.


Assuntos
Fenda Labial , Fissura Palatina , Humanos , Fenda Labial/epidemiologia , Fenda Labial/complicações , Fissura Palatina/epidemiologia , Tibet/epidemiologia , Feminino , Masculino , Pré-Escolar , Criança , Adolescente , Lactente , Adulto , Adulto Jovem , Prevalência , Pessoa de Meia-Idade , Etnicidade
9.
Heliyon ; 10(7): e29354, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38623193

RESUMO

Several COVID-19 vaccines have been approved for emergency use according to China's immunization programs. These vaccines has created hope for patients with epilepsy, because the vaccines can help to reduce their risk of becoming infected with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The aim of this study was to investigate the COVID-19 vaccine safety in patients with epilepsy. Here, we assessed the time of symptom control and the features of adverse events of seizure patients following their COVID-19 vaccinations. The results showed that adverse events of COVID-19 vaccinations for epilepsy patients included local pain at the injection site, dizziness and headache, epileptic attack, somnolence, limb weakness, limb pain, allergy, and fever. In addition, the average recovery time of the adverse events was approximately 42 h. More importantly, our study showed that it was relatively safe to vaccinate epilepsy patients who did not experience seizures for approximately 12 months prior to the immunization date.

10.
Food Sci Biotechnol ; 33(7): 1641-1649, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38623425

RESUMO

Enzymatic preparation of rare sugars as an alternative to traditional sweeteners is an effective strategy to achieve a low-calorie healthy diet. Ribose-5-phosphate isomerase B (RpiB) is a key enzyme in the non-oxidative branch of the catalytic pentose phosphate pathway. Here, we investigated the potential of Curtobacterium flaccumfaciens ZXL1 (C. flaccumfaciens ZXL1) derived RpiB (CfRpiB) in D-allose preparation. The optimal reaction conditions for recombinant CfRpiB were found experimentally to be pH 7.0, 55 °C, and no metal ions. The kinetic parameters Km, kcat, and catalytic efficiency kcat/Km were 320 mM, 4769 s-1, and 14.9 mM-1 s-1 respectively. The conversion of D-allulose by purified enzyme (1 g L-1 ) to D-allose was 13% within 1 h. In addition, homology modeling and molecular docking were used to predict the active site residues: Asp13, Asp14, Cys72, Gly73, Thr74, Gly77, Asn106, and Lys144.

11.
Artigo em Inglês | MEDLINE | ID: mdl-38621184

RESUMO

Background: In patients with cleft lip and palate (CLP), secondary alveolar bone grafting (SABG) with particulate cancellous bone marrow (PCBM) is recommended. Objective: To compare bone graft outcomes in patients with unilateral CLP, when SABG is completed before or after canine tooth eruption (ACE or BCE), as measured by cone beam computed tomography (CBCT). Methods: Patients were allocated into two cohorts, ACE and BCE. The outcomes were evaluated using CBCT, followed by univariate and multifactorial analyses. Results: A total of 468 patients (age 11.61 ± 4.03 years; male/female 288/180) were analyzed, including 282 in the BCE group (9.41 ± 1.59 years, 175/107) and 186 in the ACE group (14.95 ± 4.31 years, 113/73). Although 5-level assessment revealed no significant difference in clinical success rate (>4 points) between the BCE and ACE groups (53.90% vs. 47.85%, p = 0.20), BCE group showed significantly higher rate of bone bridges formation (73.05% vs. 62.90%, p = 0.02), which can be attributed to variations in orthodontic participation and follow-up time. Independent predictors of graft failure were wide cleft, severe oronasal fistula, no palatal bone wall, and insufficient PCBM filling (p < 0.01). Conclusions: SABG should be performed before canine eruption with more aggressive PCBM filling and oral fistula management.

12.
Exp Dermatol ; 33(4): e15078, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38610097

RESUMO

Cutaneous wound healing is a challenge in plastic and reconstructive surgery. In theory, cells undergoing mesenchymal transition will achieve re-epithelialization through mesenchymal-epithelial transition at the end of wound healing. But in fact, some pathological stimuli will inhibit this biological process and result in scar formation. If mesenchymal-epithelial transition can be activated at the corresponding stage, the ideal wound healing may be accomplished. Two in vivo skin defect mouse models and dermal-derived mesenchymal cells were used to evaluate the effect of lithium chloride in wound healing. The mesenchymal-epithelial transition was detected by immunohistochemistry staining. In vivo, differentially expressed genes were analysed by transcriptome analyses and the subsequent testing was carried out. We found that lithium chloride could promote murine cutaneous wound healing and facilitate mesenchymal-epithelial transition in vivo and in vitro. In lithium chloride group, scar area was smaller and the collagen fibres are also orderly arranged. The genes related to mesenchyme were downregulated and epithelial mark genes were activated after intervention. Moreover, transcriptome analyses suggested that this effect might be related to the inhibition of CXCL9 and IGF2, subsequent assays demonstrated it. Lithium chloride can promote mesenchymal-epithelial transition via downregulating CXCL9 and IGF2 in murine cutaneous wound healing, the expression of IGF2 is regulated by ß-catenin. It may be a potential promising therapeutic drug for alleviating postoperative scar and promoting re-epithelialization in future.


Assuntos
Cicatriz , Cloreto de Lítio , Animais , Camundongos , Cloreto de Lítio/farmacologia , Diferenciação Celular , Cicatrização , Pele
13.
J Colloid Interface Sci ; 667: 713-722, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38670014

RESUMO

The emissions of CO2 are increasing year by year, which have led to serious environmental problems. Converting CO2 into valuable fuels through photocatalysis is a promising strategy. In this research, oxygen atoms were successfully innovated into graphitic carbon nitride (CN). Additionally, cobalt porphyrin (CoTPP) was successfully loaded onto the modified carbon nitride (Co/CN). The generation of interfacial electric fields and bending bands between CN and CoTPP was demonstrated experimentally. The electrons in the CN and the holes in the CoTPP were combined to form a unique S-scheme heterojunction structure, and efficient separation of carriers was promoted. As a result, the CO conversion under visible light irradiation reached an impressive 100.70 µmol g-1 h-1. By integrating theoretical and experimental findings, this study underscores the critical role of catalyst design in enabling efficient photocatalytic CO2 reduction.

14.
J Phys Chem Lett ; 15(18): 4890-4897, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38682878

RESUMO

Organic single crystals (OSCs) with uniform morphologies and highly ordered molecular aggregations are promising for high-performance optoelectronic devices, such as organic solid-state lasers (OSSLs), organic light-emitting transistors (OLETs), and organic light-emitting diodes (OLEDs). However, manipulating OSC morphologies and aggregation is challenging. In this study, we synthesized two-dimensional (2D) OSCs of 4,4'-bis[(N-carbazole)styryl]biphenyl (BSBCz) in hexagonal and parallelogram microplate (H-MP and P-MP) forms. Both types exhibit H-aggregation in the 2D plate plane but with different molecular transition dipole moment (TDM) orientations. This leads to different photon coupling modes with H-MP and P-MP microcavities. H-MPs enable isotropic 2D-waveguiding, forming whispering gallery mode (WGM) resonators, while P-MPs create unidirectional waveguiding, forming Fabry-Pérot mode (FP) resonators. These resonators can generate low-threshold laser emissions at 467 and 473 nm, respectively, and exhibit superior lasing stability with a half-life exceeding 2 h. Our BSBCz microplate OSCs are attractive candidates to combine controlled organic microcavities with photon transporting for realizing future integrated optoelectronic devices.

15.
Angew Chem Int Ed Engl ; 63(19): e202401386, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38488840

RESUMO

Efficient water dissociation to atomic hydrogen (H*) with restrained recombination of H* is crucial for improving the H* utilization for electrochemical dechlorination, but is currently limited by the lack of feasible electrodes. Herein, we developed a monolithic single-atom electrode with Co single atoms anchored on the inherent oxide layer of titanium foam (Co1-TiOx/Ti), which can efficiently dissociate water into H* and simultaneously inhibit the recombination of H*, by taking advantage of the single-atom reverse hydrogen spillover effect. Experimental and theoretical calculations demonstrated that H* could be rapidly generated on the oxide layer of titanium foam, and then overflowed to the adjacent Co single atom for the reductive dechlorination. Using chloramphenicol as a proof-of-concept verification, the resulting Co1-TiOx/Ti monolithic electrode exhibited an unprecedented performance with almost 100 % dechlorination at -1.0 V, far superior to that of traditional indirect reduction-driven commercial Pd/C (52 %) and direct reduction-driven Co1-N-C (44 %). Moreover, its dechlorination rate constant of 1.64 h-1 was 4.3 and 8.6 times more active than those of Pd/C (0.38 h-1) and Co1-N-C (0.19 h-1), respectively. Our research sheds light on the rational design of hydrogen spillover-related electrocatalysts to simultaneously improve the H* generation, transfer, and utilization for environmental and energy applications.

16.
Biol Cybern ; 118(1-2): 21-37, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38472417

RESUMO

Motor imagery electroencephalogram (EEG) is widely employed in brain-computer interface (BCI) systems. As a time-frequency analysis method for nonlinear and non-stationary signals, multivariate empirical mode decomposition (MEMD) and its noise-assisted version (NA-MEMD) has been widely used in the preprocessing step of BCI systems for separating EEG rhythms corresponding to specific brain activities. However, when applied to multichannel EEG signals, MEMD or NA-MEMD often demonstrate low robustness to noise and high computational complexity. To address these issues, we have explored the advantages of our recently proposed fast multivariate empirical mode decomposition (FMEMD) and its noise-assisted version (NA-FMEMD) for analyzing motor imagery data. We emphasize that FMEMD enables a more accurate estimation of EEG frequency information and exhibits a more noise-robust decomposition performance with improved computational efficiency. Comparative analysis with MEMD on simulation data and real-world EEG validates the above assertions. The joint average frequency measure is employed to automatically select intrinsic mode functions that correspond to specific frequency bands. Thus, FMEMD-based classification architecture is proposed. Using FMEMD as a preprocessing algorithm instead of MEMD can improve the classification accuracy by 2.3% on the BCI Competition IV dataset. On the Physiobank Motor/Mental Imagery dataset and BCI Competition IV Dataset 2a, FMEMD-based architecture also attained a comparable performance to complex algorithms. The results indicate that FMEMD proficiently extracts feature information from small benchmark datasets while mitigating dimensionality constraints resulting from computational complexity. Hence, FMEMD or NA-FMEMD can be a powerful time-frequency preprocessing method for BCI.


Assuntos
Interfaces Cérebro-Computador , Eletroencefalografia , Imaginação , Humanos , Eletroencefalografia/métodos , Imaginação/fisiologia , Algoritmos , Processamento de Sinais Assistido por Computador , Análise Multivariada , Encéfalo/fisiologia , Simulação por Computador
17.
Cancer Med ; 13(7): e7109, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38553942

RESUMO

BACKGROUND: The value of SyMRI-derived parameters from lumbar marrow for predicting early treatment response and optimizing the risk stratification of the Revised International Staging System (R-ISS) in participants with multiple myeloma (MM) is unknown. METHODS: We prospectively enrolled participants with newly diagnosed MM before treatment. The SyMRI of lumbar marrow was used to calculate T1, T2, and PD values and the clinical features were collected. All participants were divided into good response (≥VGPR) and poor response (

Assuntos
Mieloma Múltiplo , Humanos , Masculino , Feminino , Prognóstico , Mieloma Múltiplo/diagnóstico por imagem , Mieloma Múltiplo/patologia , Medula Óssea/diagnóstico por imagem , Medula Óssea/patologia , Projetos Piloto , Estadiamento de Neoplasias , Imageamento por Ressonância Magnética , Estudos Retrospectivos
18.
Fa Yi Xue Za Zhi ; 40(1): 37-42, 2024 Feb 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38500459

RESUMO

OBJECTIVES: To investigate the toxicokinetic differences of 3,4-methylenedioxy-N-methylamphetamine (MDMA) and its metabolite 4,5-methylene dioxy amphetamine (MDA) in rats after single and continuous administration of MDMA, providing reference data for the forensic identification of MDMA. METHODS: A total of 24 rats in the single administration group were randomly divided into 5, 10 and 20 mg/kg experimental groups and the control group, with 6 rats in each group. The experimental group was given intraperitoneal injection of MDMA, and the control group was given intraperitoneal injection of the same volume of normal saline as the experimental group. The amount of 0.5 mL blood was collected from the medial canthus 5 min, 30 min, 1 h, 1.5 h, 2 h, 4 h, 6 h, 8 h, 10 h, 12 h after administration. In the continuous administration group, 24 rats were randomly divided into the experimental group (18 rats) and the control group (6 rats). The experimental group was given MDMA 7 d by continuous intraperitoneal injection in increments of 5, 7, 9, 11, 13, 15, 17 mg/kg per day, respectively, while the control group was given the same volume of normal saline as the experimental group by intraperitoneal injection. On the eighth day, the experimental rats were randomly divided into 5, 10 and 20 mg/kg dose groups, with 6 rats in each group. MDMA was injected intraperitoneally, and the control group was injected intraperitoneally with the same volume of normal saline as the experimental group. On the eighth day, 0.5 mL of blood was taken from the medial canthus 5 min, 30 min, 1 h, 1.5 h, 2 h, 4 h, 6 h, 8 h, 10 h, 12 h after administration. Liquid chromatography-triple quadrupole tandem mass spectrometry was used to detect MDMA and MDA levels, and statistical software was employed for data analysis. RESULTS: In the single-administration group, peak concentrations of MDMA and MDA were reached at 5 min and 1 h after administration, respectively, with the largest detection time limit of 12 h. In the continuous administration group, peak concentrations were reached at 30 min and 1.5 h after administration, respectively, with the largest detection time limit of 10 h. Nonlinear fitting equations for the concentration ratio of MDMA and MDA in plasma and administration time in the single-administration group and continuous administration group were as follows: T=10.362C-1.183, R2=0.974 6; T=7.397 3C-0.694, R2=0.961 5 (T: injection time; C: concentration ratio of MDMA to MDA in plasma). CONCLUSIONS: The toxicokinetic data of MDMA and its metabolite MDA in rats, obtained through single and continuous administration, including peak concentration, peak time, detection time limit, and the relationship between concentration ratio and administration time, provide a theoretical and data foundation for relevant forensic identification.


Assuntos
3,4-Metilenodioxianfetamina , Anfetaminas , N-Metil-3,4-Metilenodioxianfetamina , Ratos , Animais , Anfetamina , N-Metil-3,4-Metilenodioxianfetamina/toxicidade , 3,4-Metilenodioxianfetamina/análise , Toxicocinética , Solução Salina
19.
J Am Chem Soc ; 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38498303

RESUMO

The chlorine evolution reaction (CER) is essential for industrial Cl2 production but strongly relies on the use of dimensionally stable anode (DSA) with high-amount precious Ru/Ir oxide on a Ti substrate. For the purpose of sustainable development, precious metal decrement and performance improvement are highly desirable for the development of CER anodes. Herein, we demonstrate that surface titanium oxide amorphization is crucial to regulate the coordination environment of stabilized Ir single atoms for efficient and durable chlorine evolution of Ti monolithic anodes. Experimental and theoretical results revealed the formation of four-coordinated Ir1O4 and six-coordinated Ir1O6 sites on amorphous and crystalline titanium oxides, respectively. Interestingly, the Ir1O4 sites exhibited a superior CER performance, with a mass activity about 10 and 500 times those of the Ir1O6 counterpart and DSA, respectively. Moreover, the Ir1O4 anode displayed excellent durability for 200 h, far longer than that of its Ir1O6 counterpart (2 h). Mechanism studies showed that the unsaturated Ir in Ir1O4 was the active center for chlorine evolution, which was changed to the top-coordinated O in Ir1O6. This change of active sites greatly affected the adsorption energy of Cl species, thus accounting for their different CER activity. More importantly, the amorphous structure and restrained water dissociation of Ir1O4 synergistically prevent oxygen permeation across the Ti substrate, contributing to its long-term CER stability. This study sheds light on the importance of single-atom coordination structures in the reactivity of catalysts and offers a facile strategy to prepare highly active single-atom CER anodes via surface titanium oxide amorphization.

20.
Medicine (Baltimore) ; 103(11): e37341, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38489699

RESUMO

RATIONALE: Hepatic sinusoidal obstruction syndrome (HSOS), which includes hepatic stasis and portal hypertension, is a rare vascular disorder of the liver. It is often associated with hematopoietic stem cell transplantation. It is also possible to treat this disease using Chinese herbal medicines that contain pyrrolizidine alkaloids (PAs). This disease is extremely rare in children and poses a serious threat to their health. To our knowledge, this is the first case of HSOS in a child with PAs. PATIENT CONCERNS: We report a 4-year-old boy suffering from abdominal pain, hepatomegaly, massive ascites, elevated liver enzyme level, and severe portal hypertension as a result of the consumption of Gynura segetum (also known as Tusanqi in Chinese, a traditional herbal medicine containing PAs). DIAGNOSES: The child was finally diagnosed with PA-HSOS based on pathological diagnosis and imaging examination. INTERVENTION: With active symptomatic and supportive care and sequential anticoagulation therapy, the abdominal distension and liver function improved in the patient. OUTCOMES: The patient was eventually recovered. The levels of liver enzymes, hemoglobin, and bilirubin were normal, and the international normalized ratio fluctuated between 2.0 and 3.0 during 1-year follow-up after discharge. LESSONS: This case report emphasizes the prevention of Chinese herb-induced liver injury in children and the importance of active long-term sequential anticoagulant therapy to reduce the progressive damage of PA-HSOS in the liver.


Assuntos
Medicamentos de Ervas Chinesas , Hepatopatia Veno-Oclusiva , Hipertensão Portal , Alcaloides de Pirrolizidina , Masculino , Criança , Humanos , Pré-Escolar , Hepatopatia Veno-Oclusiva/induzido quimicamente , Hepatopatia Veno-Oclusiva/diagnóstico , Hepatopatia Veno-Oclusiva/terapia , Medicamentos de Ervas Chinesas/efeitos adversos , Alcaloides de Pirrolizidina/efeitos adversos
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