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1.
Discov Med ; 36(186): 1464-1476, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39054717

RESUMO

BACKGROUND: Monotherapy consisting of radiotherapy or chemotherapy has limited efficacy in pancreatic tumors. This study aims to investigate whether the combination of 125I brachytherapy and gemcitabine (GEM) chemotherapy has a synergistic effect on pancreatic cancer (PC). METHODS: In vitro, PANC-1 cells in the exponential phase were treated with 125I radioactive seeds (6 Gy) and GEM (30 nM). Cell proliferation, apoptosis, and mitochondrial membrane potential were measured using the Cell Counting Kit-8 (CCK-8) assay, Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining, and flow cytometry, respectively. In vivo, we examined the inhibitory effect of three different treatment regimens on tumor growth in mice when combined with 125I brachytherapy and GEM. Next, we investigated the effects of the optimal scheme among the three on the tumor microenvironment, tumor tissue morphology, tumor cell apoptosis, systemic inflammatory response, and levels of apoptosis-related proteins in the tumor. Changes in the tumor microenvironment and levels of apoptosis-related proteins were measured by Western blot. The extent of damage to tumor tissue morphology was assessed by Hematoxylin and Eosin (HE) staining. Tumor cell apoptosis was measured by TUNEL staining. Changes in inflammation-related factors were determined by Enzyme-Linked Immunosorbent Assay (ELISA). RESULTS: The results of in vitro cell experiments demonstrated that the combination of 125I radioactive seeds (6 Gy) and GEM (30 nM) had a stronger inhibitory effect on PANC-1 cells than either alone (p < 0.05). In vivo, data showed that the GEM (after 3 d) + 125I treatment group had the strongest tumor inhibition effect on PC (p < 0.05). Western blot analysis showed that the combined treatment of 125I brachytherapy and GEM caused changes in the expression of collagen and connexin in the tumor microenvironment, promoted tumor cell apoptosis, upregulated the expression of pro-apoptotic proteins, and helped to restore pancreatic function (p < 0.01). CONCLUSION: Our research results suggest that the strategy of 125I seed implantation surgery in mice after 3 days of GEM treatment has a more pronounced synergistic effect on the treatment of PC.


Assuntos
Apoptose , Braquiterapia , Desoxicitidina , Gencitabina , Radioisótopos do Iodo , Neoplasias Pancreáticas , Neoplasias Pancreáticas/radioterapia , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/tratamento farmacológico , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Desoxicitidina/uso terapêutico , Radioisótopos do Iodo/uso terapêutico , Braquiterapia/métodos , Animais , Camundongos , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Humanos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Ensaios Antitumorais Modelo de Xenoenxerto , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/efeitos da radiação , Camundongos Nus
2.
Sci Total Environ ; 937: 173482, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-38795982

RESUMO

Extensive application of rare earth element oxide nanoparticles (REE NPs) has raised a concern over the possible toxic health effects after human exposure. Once entering the body, REE NPs are primarily processed by phagocytes in particular macrophages and undergo biotic phosphate complexation in lysosomal compartment. Such biotransformation affects the target organs and in vivo fate of REE NPs after escaping the lysosomes. However, the immunomodulatory effects of intraphagolysosomal dissolved REE NPs remains insufficient. Here, europium oxide (Eu2O3) NPs were pre-incubated with phagolysosomal simulant fluid (PSF) to mimic the biotransformation of europium oxide (p-Eu2O3) NPs under acid phagolysosome conditions. We investigated the alteration in immune cell components and the hematopoiesis disturbance on adult mice after intravenous administration of Eu2O3 NPs and p-Eu2O3 NPs. Our results indicated that the liver and spleen were the main target organs for Eu2O3 NPs and p-Eu2O3 NPs. Eu2O3 NPs had a much higher accumulative potential in organs than p-Eu2O3 NPs. Eu2O3 NPs induced more alterations in immune cells in the spleen, while p-Eu2O3 NPs caused stronger response in the liver. Regarding hematopoietic disruption, Eu2O3 NPs reduced platelets (PLTs) in peripheral blood, which might be related to the inhibited erythrocyte differentiation in the spleen. By contrast, p-Eu2O3 NPs did not cause significant disturbance in peripheral PLTs. Our study demonstrated that the preincubation with PSF led to a distinct response in the immune system compared to the pristine REE NPs, suggesting that the potentially toxic effects induced by the release of NPs after phagocytosis should not be neglected, especially when evaluating the safety of NPs application in vivo.


Assuntos
Európio , Hematopoese , Lisossomos , Nanopartículas Metálicas , Óxidos , Animais , Európio/toxicidade , Camundongos , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Óxidos/toxicidade , Hematopoese/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Baço/efeitos dos fármacos , Nanopartículas/toxicidade
3.
Zhongguo Yi Liao Qi Xie Za Zhi ; 48(2): 156-159, 2024 Mar 30.
Artigo em Chinês | MEDLINE | ID: mdl-38605614

RESUMO

Objective: The distribution of the photon energy spectrum in isocenter plane of the medical linear accelerator and the influence of secondary collimator on the photon energy spectrum are studied. Methods Use the BEAMnrc program to simulate the transmission of the 6 MeV electrons and photons in 5 cm×5 cm,10 cm×10 cm,15 cm×15 cm and 20 cm×20 cm fields in treatment head of the medical linear accelerator, where a phase space file was set up at the isocenter plane to record the particle information passing through this plane. The BEAMdp program is used to analyze the phase space file, in order to obtain the distribution of the photon energy spectrum in isocenter plane and the influence of secondary collimator on the photon energy spectrum. Results: By analyzing the photon energy spectrum of a medical linear accelerator with a nominal energy of 6 MV, it is found that the secondary collimator has little effect on the photon energy spectrum; different fields have different photon energy spectrum distributions; the photon energy spectrum in different central regions of the same field have the same normalized distribution. Conclusion: In the dose calculation of radiation therapy, the influence of photon energy spectrum should be carefully considered.


Assuntos
Fótons , Planejamento da Radioterapia Assistida por Computador , Método de Monte Carlo , Fótons/uso terapêutico , Aceleradores de Partículas , Imagens de Fantasmas , Dosagem Radioterapêutica
4.
BMC Gastroenterol ; 24(1): 93, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38438972

RESUMO

PURPOSE: Hepatocellular carcinoma (HCC) has a poor prognosis, and alpha-fetoprotein (AFP) is widely used to evaluate HCC. However, the proportion of AFP-negative individuals cannot be disregarded. This study aimed to establish a nomogram of risk factors affecting the prognosis of patients with AFP-negative HCC and to evaluate its diagnostic efficiency. PATIENTS AND METHODS: Data from patients with AFP-negative initial diagnosis of HCC (ANHC) between 2004 and 2015 were collected from the Surveillance, Epidemiology, and End Results database for model establishment and validation. We randomly divided overall cohort into the training or validation cohort (7:3). Univariate and multivariate Cox regression analysis were used to identify the risk factors. We constructed nomograms with overall survival (OS) and cancer-specific survival (CSS) as clinical endpoint events and constructed survival analysis by using Kaplan-Meier curve. Also, we conducted internal validation with Receiver Operating Characteristic (ROC) analysis and Decision curve analysis (DCA) to validate the clinical value of the model. RESULTS: This study included 1811 patients (1409 men; 64.7% were Caucasian; the average age was 64 years; 60.7% were married). In the multivariate analysis, the independent risk factors affecting prognosis were age, ethnicity, year of diagnosis, tumor size, tumor grade, surgery, chemotherapy, and radiotherapy. The nomogram-based model related C-indexes were 0.762 (95% confidence interval (CI): 0.752-0.772) and 0.752 (95% CI: 0.740-0.769) for predicting OS, and 0.785 (95% CI: 0.774-0.795) and 0.779 (95% CI: 0.762-0.795) for predicting CSS. The nomogram model showed that the predicted death was consistent with the actual value. The ROC analysis and DCA showed that the nomogram had good clinical value compared with TNM staging. CONCLUSION: The age(HR:1.012, 95% CI: 1.006-1.018, P-value < 0.001), ethnicity(African-American: HR:0.946, 95% CI: 0.783-1.212, P-value: 0.66; Others: HR:0.737, 95% CI: 0.613-0.887, P-value: 0.001), tumor diameter(HR:1.006, 95% CI: 1.004-1.008, P-value < 0.001), year of diagnosis (HR:0.852, 95% CI: 0.729-0.997, P-value: 0.046), tumor grade(Grade 2: HR:1.124, 95% CI: 0.953-1.326, P-value: 0.164; Grade 3: HR:1.984, 95% CI: 1.574-2.501, P-value < 0.001; Grade 4: HR:2.119, 95% CI: 1.115-4.027, P-value: 0.022), surgery(Liver Resection: HR:0.193, 95% CI: 0.160-0.234, P-value < 0.001; Liver Transplant: HR:0.102, 95% CI: 0.072-0.145, P-value < 0.001), chemotherapy(HR:0.561, 95% CI: 0.471-0.668, P-value < 0.001), and radiotherapy(HR:0.641, 95% CI: 0.463-0.887, P-value:0.007) were independent prognostic factors for patients with ANHC. We developed a nomogram model for predicting the OS and CSS of patients with ANHC, with a good predictive performance.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Masculino , Humanos , Pessoa de Meia-Idade , Carcinoma Hepatocelular/terapia , alfa-Fetoproteínas , Prognóstico , Neoplasias Hepáticas/terapia , Pesquisa
5.
J Ethnopharmacol ; 325: 117846, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38301982

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Radix Astragali, a versatile traditional Chinese medicinal herb, has a rich history dating back to "Sheng Nong's herbal classic". It has been employed in clinical practice to address various ailments, including depression. One of its primary active components, total flavonoids from Astragalus (TFA), remains unexplored in terms of its potential antidepressant properties. This study delves into the antidepressant effects of TFA using a mouse model subjected to chronic unpredictable mild stress (CUMS). AIMS OF THE STUDY: The study aimed to scrutinize how TFA influenced depressive behaviors, corticosterone and glutamate levels in the hippocampus, as well as myelin-related protein expression in CUMS mice. Additionally, it sought to explore the involvement of the Wnt/ß-catenin/Olig2/Sox10 signaling axis as a potential antidepressant mechanism of TFA. MATERIALS AND METHODS: Male C57BL/6 mice were subjected to CUMS to induce depressive behaviors. TFA were orally administered at two different doses (50 mg/kg and 100 mg/kg). A battery of behavioral tests, biochemical analyses, immunohistochemistry, UPLC-MS/MS, real-time PCR, and Western blotting were employed to evaluate the antidepressant potential of TFA. The role of the Wnt/ß-catenin/Olig2/Sox10 signaling axis in the antidepressant mechanism of TFA was validated through MO3.13 cells. RESULTS: TFA administration significantly alleviated depressive behaviors in CUMS mice, as evidenced by improved sucrose preference, reduced immobility in tail suspension and forced swimming tests, and increased locomotor activity in the open field test. Moreover, TFA effectively reduced hippocampal corticosterone and glutamate levels and promoted myelin formation in the hippocampus of CUMS mice. Then, TFA increased Olig2 and Sox10 expression while inhibiting the Wnt/ß-catenin pathway in the hippocampus of CUMS mice. Finally, we further confirmed the role of TFA in promoting myelin regeneration through the Wnt/ß-catenin/Olig2/Sox10 signaling axis in MO3.13 cells. CONCLUSIONS: TFA exhibited promising antidepressant effects in the CUMS mouse model, facilitated by the restoration of myelin sheaths and regulation of corticosterone, glutamate, Olig2, Sox10, and the Wnt/ß-catenin pathway. This research provides valuable insights into the potential therapeutic application of TFA in treating depression, although further investigations are required to fully elucidate the underlying molecular mechanisms and clinical relevance.


Assuntos
Corticosterona , Depressão , Fator de Transcrição 2 de Oligodendrócitos , Masculino , Animais , Camundongos , Depressão/tratamento farmacológico , Depressão/metabolismo , Flavonoides/farmacologia , Cromatografia Líquida , beta Catenina/metabolismo , Camundongos Endogâmicos C57BL , Espectrometria de Massas em Tandem , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Antidepressivos/metabolismo , Hipocampo , Glutamatos/metabolismo , Glutamatos/farmacologia , Estresse Psicológico/tratamento farmacológico , Estresse Psicológico/metabolismo , Modelos Animais de Doenças , Fatores de Transcrição SOXE/genética , Fatores de Transcrição SOXE/metabolismo
6.
Brain Res ; 1823: 148678, 2024 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-37979605

RESUMO

Depression is characterized by a significant sex disparity, with higher rates observed in women compared to men. This study aimed to investigate the impact of sex on depressive behaviors and explore the underlying mechanisms using a corticosterone (CORT)-induced depression model in mice. Behavioral tests, Nissl staining, UPLC-MS/MS, and Western blot analysis were performed to assess behavioral changes, as well as neuronal alterations, neurotransmitter levels, and protein expressions in the hippocampus. The mice in the model group exhibited sex-specific anxiety- and depression-like behaviors. Nissl staining revealed structural abnormalities in the CA3 region of the hippocampus in females. Neurotransmitter analysis indicated decreased serotonin and norepinephrine levels in both sexes, while glutamate levels were elevated in females. Furthermore, female mice demonstrated elevated serum CORT levels. Western blot analysis revealed sex-specific alterations in specific protein expression. Female mice exhibited downregulated glucocorticoid receptor and brain-derived neurotrophic factor expression, whereas male mice showed minimal changes. Additionally, female mice displayed reduced phosphorylated AKT, phosphorylated PI3K, and phosphorylated mTOR levels. These findings enhance our understanding of sex-specific differences in the CORT-induced depression model and provide insights into the underlying mechanisms of depression. This research emphasizes sex in depression studies and supports tailored interventions.


Assuntos
Corticosterona , Depressão , Humanos , Feminino , Camundongos , Masculino , Animais , Depressão/induzido quimicamente , Depressão/metabolismo , Caracteres Sexuais , Cromatografia Líquida , Espectrometria de Massas em Tandem , Hipocampo/metabolismo , Neurotransmissores/metabolismo , Modelos Animais de Doenças , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Comportamento Animal
7.
J Org Chem ; 88(23): 16196-16215, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37955519

RESUMO

A simple and efficient method for the ruthenium-catalyzed 1,6-hydroalkylation of para-quinone methides (p-QMs) with ketones via the in situ activation of C(sp3)-H bonds has been disclosed. Without the need for preactivation of the substrates and oxidant, a broad range of p-QMs and ketones are well tolerated, producing the expected 1,6-hydroalkylation products with moderate to good yields. Step-by-step control experiments and DFT calculation were conducted systematically to gain insights for the plausible reaction mechanism. This finding may have potential application in the selective diarylmethylation of ketones at the α-C position in organic synthesis.

8.
Chem Asian J ; 18(23): e202300792, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37845179

RESUMO

A simple and efficient method for the synthesis of diarylmethyl-functionalized anilines through the hexafluoroisopropanol (HFIP)-mediated regioselective 1,6-hydroarylation reaction of para-quinone methides (p-QMs) with anilines under catalyst- and additive-free conditions is reported. Various kinds of p-QMs and amines (e. g. primary, secondary and tertiary amines) are well tolerated in this transformation without the pre-protection of amino group, and the corresponding products could be generated with good to excellent yields and satisfactory regioselectivity under the optimized reaction conditions. In addition to adaptable amine compounds, indoles and their derivatives are also compatible with this reaction system. This transformation can be easily extended to a gram scale-synthesis level to synthesize the target product. Furthermore, it is worth noting that some complex small aniline molecules with biological activity can be selectively modified using this method. The possible reaction mechanism is proposed through the step-by-step control experiments and DFT calculations, showing that the key process for achieving the regioselective 1,6-hydroarylation of p-QMs is the hydrogen bonding effect of HFIP to substrates.

9.
Environ Health (Wash) ; 1(1): 15-31, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37552709

RESUMO

Enveloped viruses have been the leading causative agents of viral epidemics in the past decade, including the ongoing coronavirus disease 2019 outbreak. In epidemics caused by enveloped viruses, direct contact is a common route of infection, while indirect transmissions through the environment also contribute to the spread of the disease, although their significance remains controversial. Bridging the knowledge gap regarding the influence of interfacial interactions on the persistence of enveloped viruses in the environment reveals the transmission mechanisms when the virus undergoes mutations and prevents excessive disinfection during viral epidemics. Herein, from the perspective of the driving force, partition efficiency, and viral survivability at interfaces, we summarize the viral and environmental characteristics that affect the environmental transmission of viruses. We expect to provide insights for virus detection, environmental surveillance, and disinfection to limit the spread of severe acute respiratory syndrome coronavirus 2.

10.
Biomacromolecules ; 23(11): 4439-4468, 2022 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-36195577

RESUMO

Cellulose nanocrystals (CNCs) are hydrophilic nanoparticles extracted from biomass with properties and functions different from cellulose and are being developed for property-oriented applications such as high stiffness, abundant active groups, and biocompatibility. It has broad application prospects in the field of composite materials, while the dispersibility of the CNC in polymers is the key to its application performance. Many reviews have discussed in-depth the modification strategies to improve the dispersibility of the CNC and summarized all characterization for the CNC, but there are no reviews on the in-depth exploration of dispersion characterization. This review is a comprehensive summary of the characterization of CNC dispersion in the matrix in terms of direct observation, indirect evaluation, and quantified evaluation, summarizing how and why different characterization tools reveal dispersibility. In addition, "decision tree" flowcharts are presented to provide the reader with a reference for selecting the appropriate characterization method for a specific composite.


Assuntos
Celulose , Nanopartículas , Celulose/química , Polímeros/química , Nanopartículas/química , Interações Hidrofóbicas e Hidrofílicas
11.
Chem Commun (Camb) ; 58(71): 9878-9881, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35972212

RESUMO

A new bimetallic complex containing a 4'-ferrocenyl-(2,2':6',2''-terpyridine)palladium core with polyethylene glycol-based pyridine is applied in seeded-growth self-assembled supramolecular polymerization, which affords nanoribbons with controllable lengths and the process follows a first-order reaction kinetics. This approach is successfully demonstrated for a bimetallic organic complex for the first time.

12.
Environ Pollut ; 308: 119659, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35738515

RESUMO

Exposure to electronic and electrical waste (e-waste) has been related to a few adverse health effects. In this study, sediment samples from an e-waste recycling town in China were collected, and aryl hydrocarbon receptor (AhR) agonists in the samples were identified using an effect-directed analysis (EDA) strategy. The CBG2.8D cell line reporter gene bioassay was used as a toxicity test, while suspect screening against chemical databases was performed for potential AhR agonist identification where both gas chromatography- and liquid chromatography-high resolution mass spectrometry analyses were run. When the original sample extract showed high AhR-mediated activity, sample fractionation was performed, and fractions exhibiting high bioactivity were chemically analyzed again to reveal the corresponding AhR agonists. In total, 23 AhR agonists were identified, including 14 commonly known ones and 9 new ones. Benzo [k]fluoranthene and 6-nitrochrysene were the dominant AhR agonists, covering 16-71% and 2.7-12%, respectively, of the AhR activation effects measured in the parent extracts. The newly identified AhR-active chemicals combined explained 0.13-0.20% of the parent extracts' effects, with 7,12-dimethylbenz [a]anthracene and 8,9,11-trimethylbenz [a]anthracene being the major contributors. A diagnostic isomer ratio analysis of polycyclic aromatic hydrocarbons suggested that the major source of AhR agonists identified in these e-waste related sediment samples were probably petroleum product combustion and biomass combustion. In the future, for a more comprehensive AhR agonist investigation, in-house chemical synthesis and purification, and, when necessary, a secondary sample fractionation, would be beneficial.


Assuntos
Resíduo Eletrônico , Hidrocarbonetos Policíclicos Aromáticos , Antracenos/análise , Resíduo Eletrônico/análise , Cromatografia Gasosa-Espectrometria de Massas , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Receptores de Hidrocarboneto Arílico/metabolismo
13.
Environ Int ; 164: 107273, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35526298

RESUMO

Human uptake abundance of microplastics via various pathways, and they accumulate in human liver, kidney, gut and even placenta (especially with a diameter of 1 µm or less). Recent scientific studies have found that exposure to microplastics causes intestinal inflammation and liver metabolic disorder, but it remains largely unknown that whether the damage and inflammation may cause further development of severe diseases. In this study, we discovered one of such potential diseases that may be induced by the exposure to small-sized microplastics (with a diameter of 1 µm) performing a multi-organ and multi-omics study comprising metabolomics and microbiome approaches. Unlike other animal experiments, the dosing strategy was applied in mice according to the daily exposure of the highly exposed population, which was more environmentally relevant and reflective of real-world human exposure. Our studies on the gut-liver axis metabolism have shown that the crosstalk between the gut and liver ultimately leaded to insulin resistance and even diabetes. We proactively verified this hypothesis by measuring the levels of fasting blood glucose and fasting insulin, which were found significantly elevated in the mice with microplastics exposure. These results indicate the urgent need of large-scale cohort evaluation on epidemiology and prognosis of insulin resistance after microplastics exposure in future.


Assuntos
Resistência à Insulina , Microplásticos , Animais , Humanos , Inflamação/metabolismo , Fígado/metabolismo , Camundongos , Plásticos/metabolismo , Poliestirenos/metabolismo
14.
Environ Pollut ; 306: 119369, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35513195

RESUMO

Electronic waste (e-waste) pollution is of great concern due to the release of hazardous chemicals during the improper e-waste disposal. Many chemicals leached from e-waste were reported to pose estrogenic effects. To date, little is known regarding the occurrence and biological effects of estrogenic chemicals in sediments near an e-waste area. In this study, an effect-directed analysis (EDA) is applied to determine the estrogenic chemicals in sediments of four sites collected from a typical e-waste recycling city in China. Following screening with the ER-CALUX assay, the extract of sample with the most potent effect was subjected in fractionation using reverse phase liquid chromatography. Based on a target analysis for the active fractions, four compounds, including estrone, 17ß-estradiol, 17α-ethinylestradiol and bisphenol A, were identified, and these contributed to 17% of the total toxic effects in the sample. A further nontarget analysis screened four candidates, namely diethylstilbestrol (DES), hexestrol (HES), nandrolone and durabolin, and the total contribution was found to be 48% from the active sample. Specifically, DES and HES were only detected in the active sample and were found to be the primary drivers of estrogenic effects. An examination of the identified chemicals in the four sites indicated that these estrogenic chemicals may originate from e-waste recycling, livestock excretion and domestic waste. These findings uncovered the estrogenic pollutants in sediments from an e-waste area. Considering single endpoint in biological assay is not abundant to screen chemicals with different toxic effects, further EDA studies with multiple endpoints are required to better understand the occurrence of representative or unknown chemicals in e-waste-polluted areas.


Assuntos
Resíduo Eletrônico , Poluentes Químicos da Água , Monitoramento Ambiental/métodos , Estrogênios/análise , Estrona/análise , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
15.
Chem Soc Rev ; 51(6): 1926-1982, 2022 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-35083990

RESUMO

With the upcoming trend of Big Data era, some new types of memory technologies have emerged as substitutes for the traditional Si-based semiconductor memory devices, which are encountering severe scaling down technical obstacles. In particular, the resistance random access memory (RRAM) and magnetic random access memory (MRAM) hold great promise for the in-memory computing, which are regarded as the optimal strategy and pathway to solve the von Neumann bottleneck by high-throughput in situ data processing. As far as the active materials in RRAM and MRAM are concerned, organic semiconducting materials have shown increasing application perspectives in memory devices due to their rich structural diversity and solution processability. With the introduction of metal elements into the backbone of molecules, some new properties and phenomena will emerge accordingly. Consequently, the RRAM and MRAM devices based on metal-containing organic compounds (including the small molecular metal complexes, metallopolymers, metal-organic frameworks (MOFs) and organic-inorganic-hybrid perovskites (OIHPs)) have been widely explored and attracted intense attention. In this review, we highlight the fundamentals of RRAM and MRAM, as well as the research progress of the applications of metal-containing organic compounds in both RRAM and MRAM. Finally, we discuss the challenges and future directions for the research of organic RRAM and MRAM.

16.
Carbohydr Polym ; 275: 118708, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34742433

RESUMO

Inspired from the ancient China philosophy of "coupling hardness with softness", we attempted the combination of rigid cellulose nanocrystals (CNC) and elastic rubbers to solve the limitations of structural brittleness and water sensitivity of CNC-based aerogels. Three rubber chains with the different chemical structures (silicon rubber, 1,2-polybutadiene, styreneic block copolymer) were covalently bonded on the CNC porous skeleton based on thiol-ene click chemistry, to fabricate the CNC/rubber composite aerogels. With the introduction of moderate loading levels of rubber, the composites aerogels exhibited low density and shrinkage, high porosity and specific surface area and improved mechanical performance. Furthermore, the presence of rubber components completely changed the hydrophilic nature of cellulose skeleton as the hydrophobic aerogels, contributing the superior solvents resistance and self-cleaning property. With their advantages on mechanical stability, heat insulation and hydrophobicity, the fabricated aerogels in this study exhibited the high added values in various potential applications.

17.
Environ Sci Technol ; 55(12): 8191-8202, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34086441

RESUMO

As typical brominated flame retardants (BFRs), tetrabromobisphenol A (TBBPA) and its derivative TBBPA-bis(2,3-dibromopropyl ether) (TBBPA-BDBPE) are ubiquitous in various environmental compartments. However, the potential health risk posed by these compounds, especially at environmentally relevant levels, remains unclear. In this study, using adult male mice, we investigated the toxicity of orally administered TBBPA and TBBPA-BDBPE at an environmentally relevant dose (57 nmol/kg body weight). After a single exposure and daily exposure, we assessed lipid metabolism homeostasis, the transcriptome, and immune cell components in the liver. We found that the single exposure to TBBPA or TBBPA-BDBPE alone increased the number of hepatic macrophages, induced alterations in the levels of lipids, including triacylglycerol and free fatty acids, and caused transcriptome perturbation. The results from the daily administration groups showed that TBBPA and TBBPA-BDBPE both significantly increased the triacylglycerol content; however, the elevation of hepatic macrophages was observed only in the TBBPA-BDBPE treatment group. This study confirmed that environmentally relevant levels of TBBPA and TBBPA-BDBPE are toxic to the liver. Our findings revealed that dysfunction of the liver is a health concern, following exposure to BFRs, even at very low concentrations. The chronic effects induced by TBBPA and its derivatives should be further investigated.


Assuntos
Retardadores de Chama , Bifenil Polibromatos , Animais , Éter , Retardadores de Chama/toxicidade , Fígado , Masculino , Camundongos , Bifenil Polibromatos/toxicidade
18.
Chemistry ; 26(63): 14474-14480, 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-32776399

RESUMO

A one-pot sequential strategy to construct phosphonamidates has been developed by generating phosphonites in situ from arylmagnesium bromides and triethyl phosphite followed by treatment with iodine and amines. A variety of phosphonamidates were obtained with good to excellent yields at room temperature from easily available materials.

19.
Sci Rep ; 10(1): 11993, 2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32686746

RESUMO

In this paper, we combine inverse design concept and direct binary search algorithm to demonstrate three ultra-compact high efficiency and low crosstalk on-chip integrated optical interconnection basic devices in the entire wavelength range of 1,400-1600 nm based on silicon-on-insulator platform. A 90-degree waveguide bend with a footprint of only 2.4 × 2.4 µm2 is designed, whose transmission efficiency up to 0.18 dB. A waveguide crossing with a footprint of only 2.4 × 2.4 µm2 is designed, which can provide insertion loss of less than 0.5 dB and crosstalk (CL) of lower than - 19 dB. A same direction waveguide crossing with footprint of only 2.4 × 3.6 µm2 is designed, which can provide the insertion loss of less than 0.56 dB and the crosstalk of lower than - 21 dB. Then, we use them to form several ultra-compact optical interconnect basic structures and performed the simulation calculation. They overall achieve high performance. This will significantly improve the integration density.

20.
Org Lett ; 22(12): 4588-4592, 2020 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-32281804

RESUMO

A new family of pyrrolyl-acylhydrazones anchored with two BF2 units, named BOAPY, have been developed as BODIPY-like and unsymmetrical bis(BF2) chromophores via a simple one-pot reaction. The easily accessible scaffold enjoys excellent diversity due to the structural versatilities of 2-formylpyrroles and acylhydrazines. BOAPYs exhibit good molar absorption coefficients, large Stokes shifts, and excellent chemical stability. More importantly, most of them display excellent fluorescence quantum yields both in solution and the solid state (up to 0.88 and 0.64, respectively).

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