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1.
Chem Commun (Camb) ; 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38716634

RESUMO

Rh-catalyzed three-component C(sp3)/C(sp2)-H activation has been achieved through a two-directing group strategy. This protocol provides a convenient and efficient pathway for the construction of diverse 8-alkyl quinoline derivatives in one-pot. Furthermore, mechanistic studies revealed that the first C-H amidation was significantly faster than the sequential C-H alkylation.

2.
ACS Appl Mater Interfaces ; 15(50): 58806-58814, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38055035

RESUMO

Triboelectric nanogenerators (TENGs) are an emerging class of energy harvesting devices with considerable potential across diverse applications, including wearable electronic devices and self-powered sensors. However, sustained contact, friction, and incidental scratches during operation can lead to a deterioration in the electrical output performance of the TENG, thereby reducing its overall service life. To address this issue, we developed a self-healing elastomer by incorporating disulfide bonds and metal coordination bonds into the polyurethane (PU) chain. The resulting elastomer demonstrated exceptional toughness, with a high value of 85 kJ m-3 and an impressive self-healing efficiency of 85.5%. Specifically, the TENG based on that self-healing PU elastomer generated a short circuit current of 12 µA, an open circuit voltage of 120 V, and a transfer charge of 38.5 nC within a 2 cm × 2 cm area, operating in contact-separation mode. With an external resistance of 20 MΩ, the TENG achieved a power density of 2.1 W m-2. Notably, even after self-healing, the electrical output performance of the TENG was maintained at 95% of the undamaged device. Finally, the self-healing TENG was employed to construct a self-powered noncontact sensing system that can be applied to monitor human motion accurately. This research may expand the application prospects of PU materials in future human-computer interaction and self-powered sensing fields.

3.
Biomacromolecules ; 24(11): 4605-4621, 2023 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-37917193

RESUMO

With the emergence of challenges in the environmental degradation and resource scarcity fields, the research of biobased self-healing polyurethane (BSPU) has become a prevailing trend in the technology of the polyurethane industry and a promising direction for developing biomass resources. Here, the production of BSPU from lignocellulose, vegetable oil, chitosan, collagen, and coumarin is classified, and the principles of designing polyurethane based on compelling examples using the latest methods and current research are summarized. Moreover, the impact of biomass materials on self-healing and mechanical properties, as well as the tailored performance method, are presented in detail. Finally, the applications of BSPU in biomedicine, sensors, coatings, etc. are also summarized, and the possible challenges and development prospects are explored to helpfully make progress in the development of BSPU. These findings demonstrate valuable references and practical significance for future BSPU research.


Assuntos
Quitosana , Poliuretanos , Biomassa
4.
Mol Reprod Dev ; 90(10-11): 774-781, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37733694

RESUMO

Male fertility declines with age. The mevalonate pathway, through which cholesterol and nonsteroidal isoprenoids are synthesized, plays key role in metabolic processes and is an essential pathway for cholesterol production and protein prenylation. Male reproductive aging is accompanied by dramatic changes in the metabolic microenvironment of the testis. Since the mevalonate pathway has an important role in spermatogenesis, we attempted to explore the association between male reproductive aging and the mevalonate pathway to explain the mechanism of male reproductive aging. Alterations in the mevalonate pathway may affect male reproductive aging by decreasing cholesterol synthesis and altering testis protein prenylation. Decreased cholesterol levels affect cholesterol modification, testosterone production, and remodeling of germ cell membranes. Aging-related metabolic disorders also affect the metabolic coupling between somatic cells and spermatogenic cells, leading to male fertility decline. Therefore, we hypothesized that alterations in the mevalonate pathway represent one of the metabolic causes of reproductive aging.


Assuntos
Colesterol , Ácido Mevalônico , Masculino , Humanos , Ácido Mevalônico/metabolismo , Colesterol/metabolismo , Reprodução , Testículo/metabolismo
5.
Transl Cancer Res ; 12(4): 887-903, 2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37180666

RESUMO

Background: Both metastasis and immune resistance are huge obstacle in lung adenocarcinoma (LUAD) treatment. Multiple studies have shown that the ability of tumor cells to resist anoikis is closely related to the metastasis of tumor cells. Methods: In this study, the risk prognosis signature related to anoikis and immune related genes (AIRGs) was constructed by cluster analysis and the least absolute shrinkage and selection operator (LASSO) regression by using The Cancer Genome Atlas (TCGA) Program and the Gene Expression Omnibus (GEO) database. Kaplan-Meier (K-M) curve described the prognosis in the different groups. Receiver operating characteristic (ROC) was applied to evaluate the sensitivity of this signature. Principal component analysis (PCA), t-distributed stochastic neighbor embedding (t-SNE), independent prognostic analysis, and nomogram were utilized to assess the validity of the signature. In addition, we used multiple bioinformatic tools to analyze the function between different groups. Finally, mRNA levels were analyzed by quantitative real-time PCR (qRT-PCR). Results: The K-M curve showed a worse prognosis for the high-risk group compared to that for the low-risk group. ROC, PCA, t-SNE, independent prognostic analysis and nomogram showed well predictive capabilities. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that differential genes were mainly enriched in immunity, metabolism, and cell cycle. In addition, multiple immune cells and targeted drugs differed in the two risk groups. Finally, we found that the mRNA levels of AIRGs were remarkably different in normal versus cancer cells. Conclusions: In short, we established a new model about anoikis and immune, which can well predict prognosis and immune response.

6.
Huan Jing Ke Xue ; 43(10): 4338-4347, 2022 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-36224120

RESUMO

Marine shipping emissions have important impacts on air quality and climate. This type of anthropogenic emission remains largely unclear due to complex vessel types and activities. A coastal site near the Ningbo-Zhoushan port along the East China Sea was selected for this study, representing one of the hotspot regions globally with the most intensive shipping activities, in combination with vessels for both domestic and international transportation. Long-term temporal variations in key gaseous and particulate pollutants were obtained at the site using in-situ measurements, and the vessel speed associated with each classified vessel type was obtained according to the automatic identification system (AIS). In combination of backward trajectories, we were able to identify the periods predominated by the surrounding vessel emissions (in warm seasons, dominated by vessels in full operation or idle mode) or influenced by continental outflow (in cold season). We found that emissions of sulphur dioxide (SO2), nitrogen oxides (NOx), and black carbon (BC) aerosol were highly correlated with high-speed vessels, whereas carbon monoxide (CO) was likely related to lower operation speed. The total particulate matter (PM) was not directly linked to vessel activities. The enhancement factor in operation mode compared to that in idle mode was approximately 1-4 for most pollutants. This direct ambient observation of the emissions from a range of mixed vessel types may provide a basis for evaluating the shipping emission inventory.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Ambientais , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Monóxido de Carbono/análise , China , Monitoramento Ambiental , Óxidos de Nitrogênio/análise , Material Particulado/análise , Navios , Dióxido de Enxofre , Emissões de Veículos/análise
7.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 30(5): 1590-1596, 2022 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-36208271

RESUMO

OBJECTIVE: To explore the transcriptional gene expression profile up-regulated in human macrophages stimulated by interferon-γ (IFN-γ) and the underlying intracellular signaling mechanisms. METHODS: RNA-seq was used to sequence and compare the differential gene expression profiles of human macrophage cell line U937 before and after IFN-γ stimulation, and the significantly up-regulated genes were screened out, which were verified by fluorescence-based real-time quantitative polymerase chain reaction (qPCR) in U937 and THP1 cell lines, respectively. JAK/STAT, MAPK/ERK and PI3K/AKT pathway inhibitors were added to simultaneously to the cultured U937 cells upon IFN-γ priming to detect their effects on the expressions of the up-regulated genes to explore the key regulatory mechanisms. RESULTS: RNA-seq and qPCR results showed that, the well-recognized chemokines CXCL9, CXCL10 and CXCL11, the APOL family including APOL1, APOL2, APOL3, APOL4, APOL6 and GBP family GBP1, GBP2, GBP3, GBP4 and GBP5 as well were significantly up-regulated in IFN-γ-stimulated U937 cells. JAK/STAT3 pathway inhibitor inhibited the upregulation of APOL1, APOL4, GBP1, GBP4 and GBP5 genes induced by IFN-γ, while MAPK/ERK pathway inhibitor inhibited the upregulation of CXCL10 gene. PI3K/AKT pathway inhibitor inhibited the upregulation of APOL1,APOL4, APOL6, GBP1 and GBP5 genes induced by IFN-γ, all three signal pathway inhibitors could inhibit the upregulation of CXCL9 gene, and none of them could inhibit the upregulation of APOL3 gene. CONCLUSION: Upon IFN-γ stimulation, some family molecules of APOL and GBP in macrophages are significantly up-regulated, and PI3K/AKT, JAK/STAT3 and MAPK/ERK pathways have positive regulation on their expressions, respectively.


Assuntos
Apolipoproteína L1 , Interferon gama , Apolipoproteína L1/farmacologia , Humanos , Interferon gama/farmacologia , Macrófagos/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais
8.
J Biol Chem ; 298(5): 101818, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35278432

RESUMO

Gonadal white adipose tissue (gWAT) can regulate gametogenesis via modulation of neuroendocrine signaling. However, the effect of gWAT on the local microenvironment of the gonad was largely unknown. Herein, we ruled out that gWAT had a neuroendocrine effect on gonad function through a unilateral lipectomy strategy, in which cutting off epididymal white adipose tissue could reduce seminiferous tubule thickness and decrease sperm counts only in the adjacent testis and epididymis of the affected gonad. Consistent with the results in males, in females, ovary mass was similarly decreased by lipectomy. We determined that the defects in spermatogenesis were mainly caused by augmented apoptosis and decreased proliferation of germ cells. Transcriptome analysis suggested that lipectomy could disrupt immune privilege and activate immune responses in both the testis and ovary on the side of the lipectomy. In addition, lipidomics analysis in the testis showed that the levels of lipid metabolites such as free carnitine were elevated, whereas the levels of glycerophospholipids such as phosphatidylcholines and phosphatidylethanolamines were decreased, which indicated that the metabolic niche was also altered. Finally, we show that supplementation of phosphatidylcholine and phosphatidylethanolamine could partially rescue the observed phenotype. Collectively, our findings suggest that gWAT is important for gonad function by not only affecting whole-body homeostasis but also via maintaining local metabolic and immune niches.


Assuntos
Tecido Adiposo Branco , Gônadas , Tecido Adiposo/metabolismo , Tecido Adiposo Branco/metabolismo , Animais , Epididimo , Feminino , Masculino , Camundongos , Espermatogênese , Testículo/metabolismo
9.
Materials (Basel) ; 14(19)2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34639935

RESUMO

Mechanical properties play a key role in the failure of dental implants. Dental implants require fatigue life testing before clinical application, but this process takes a lot of time. This study investigated the effect of various loading angles and implant lengths on the static fracture and fatigue life of dental implants. Implants with lengths of 9 mm and 11 mm were prepared. Static fracture tests and dynamic fatigue life tests were performed under three loading angles (30°, 40°, and 50°), and the level arm and bending moment were measured. After that, the fracture morphology and fracture mode of the implant were observed. The results showed that 9 mm length implants have a higher static failure load and can withstand greater bending moments, while 11 mm length implants have a longer fatigue life. In addition, as the loading angle increases, the static strength and bending moment decrease linearly, and the fatigue life shows an exponential decrease at a rate of three times. Increasing the loading angle reduces the time of the implant fatigue test, which may be an effective method to improve the efficiency of the experiment.

10.
Zhongguo Zhen Jiu ; 40(3): 273-6, 2020 Mar 12.
Artigo em Chinês | MEDLINE | ID: mdl-32270640

RESUMO

Based on the analysis of the present situation of standardization of moxibustion, it is found that the published standards of acupuncture and moxibustion are predominated at acupoint standard and acupuncture manipulation standard. Moxibusiton standardization mainly focuses on the manipulation. It is relatively lack of the standards of moxibustion materials and device. Four suggestions are put forward on the development strategies of moxibustion standardization: 1. Rectify the current situation that more attention paid to acupuncture rather than moxibustion, strengthen the inheritance of traditional experiences and the excavation of ancient literature, expand the indications of moxibustion and confirm the clinical effect of it. 2. Promote the whole process of moxibustion standardization, starting from moxibustion technique to its material, device and manipulation. 3. Enhance the equipment construction of moxibustion, combine with other build engineering disciplines, e.g. artificial intelligence and communication technology, and construct a multi-disciplinary intersection system. 4. Improve the promotion and development mode of moxibustion, propel all-round development of moxibustion in the clinical application, promotion mode and standardization construction, etc.


Assuntos
Moxibustão/normas , Pontos de Acupuntura , Inteligência Artificial , Humanos
11.
Nat Prod Bioprospect ; 8(4): 321-334, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29959744

RESUMO

LC-MS-based metabolomics could have a major impact in the study of natural products, especially in its metabolism, toxicity and activity. This review highlights recent applications of metabolomics approach in the study of metabolites and toxicity of natural products, and the understanding of their effects on various diseases. Metabolomics has been employed to study the in vitro and in vivo metabolism of natural compounds, such as osthole, dehydrodiisoeugenol, and myrislignan. The pharmacological effects of natural compounds and extracts were determined using metabolomics technology combined with diseases models in animal, including osthole and nutmeg extracts. It has been demonstrated that metabolomics is a powerful technology for the investigation of xenobiotics-induced toxicity. The metabolism of triptolide and its hepatotoxicity were discussed. LC-MS-based metabolomics has a great potential in the druggability of natural products. The application of metabolomics should be broadened in the field of natural products in the future.

12.
Gastroenterol Res Pract ; 2018: 4914201, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29805443

RESUMO

AIM: Gastrectomy with lymph node dissection is standard treatment in gastric cancer. This study aimed to explore whether preoperative investigation finds could predict lymph node metastatic scope in gastric carcinoma so that the optimal surgical procedure could be selected. MATERIALS AND METHODS: Radical gastrectomy patients (n = 378) were separated into two groups according to the lymph node metastatic scope. Univariate and multivariate analyses of preoperative examination results were performed to identify the predictors of metastatic scope. ROC curves were constructed, and the area under the curve (AUC) was calculated to estimate diagnostic values. RESULTS: Serum CEA (OR: 3.73; 95% CI: 1.84-7.56; P ≤ 0.001), tumor size (OR: 2.07; 95% CI: 1.08-3.98; P = 0.03), and CT examination results (OR: 17.81; 95% CI: 9.18-34.55; P ≤ 0.001) were identified as independent predictors. The AUC proved that they possessed significant diagnostic value. When CT examination was negative, the combination of serum CEA and tumor size showed high specificity (95.3%; 164/172), negative predictive value (92.7%; 164/177), and accuracy (89.0%; 170/191). CONCLUSIONS: Preoperative serum CEA, tumor size, and CT examination are independent predictors of lymph node metastatic scope and can be used for selecting the appropriate lymphadenectomy pattern in gastric cancer patients.

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