Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
1.
Br J Cancer ; 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38822145

RESUMO

BACKGROUND: Sunitinib has emerged as the primary treatment for advanced or metastatic clear cell renal cell carcinoma (ccRCC) due to its significant improvement in patients' average survival time. However, drug resistance and adverse effects of sunitinib pose challenges to its clinical benefits. METHODS: The differentially expressed genes (DEGs) associated with sunitinib sensitivity and resistance in ccRCC were investigated. Cell counting kit-8, plate colony formation, flow cytometry and subcutaneous xenograft tumor model assays were employed to explore the effects of PDZK1 on ccRCC. Further research on the molecular mechanism was conducted through western blot, co-immunoprecipitation, immunofluorescence co-localization and immunohistochemical staining. RESULTS: We elucidated that PDZK1 is significantly downregulated in sunitinib-resistant ccRCC specimens, and PDZK1 negatively regulates the phosphorylation of PDGFR-ß and the activation of its downstream pathways through interaction with PDGFR-ß. The dysregulated low levels of PDZK1 contribute to inadequate inhibition of cell proliferation, tumor growth, and insensitivity to sunitinib treatment. Notably, our preclinical investigations showed that miR-15b antagomirs enhance sunitinib cytotoxic effects against ccRCC cells by upregulating PDZK1 levels, suggesting their potential in overcoming sunitinib resistance. CONCLUSIONS: Our findings establish the miR-15b/PDZK1/PDGFR-ß axis as a promising therapeutic target and a novel predictor for ccRCC patients' response to sunitinib treatment.

2.
Environ Manage ; 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38421384

RESUMO

Payment for watershed ecosystem services (PES) has been applied to water conservation and poverty reduction in an increasing number of developing countries. This study evaluates the effect of payment for watershed ecosystem services on farmers' income in conservation intervention areas using a difference-in-differences model and a panel dataset that covers 18 countries in the Xin'an River Basin in China for fourteen consecutive years (2006-2019). The results show that PES programs increase farmers' income and that the poverty reduction effect is sustainable. The PES programs mainly increase the farmers' income in conservation intervention areas through two paths: triggering the transfer of agricultural labor and promoting agricultural restructuring. PES programs are pro-poor and more conducive to increasing the income of farmers in upstream regions and counties with lower levels of economic development. This paper reveals the specific role played by PES in promoting rural poverty reduction in developing countries, providing insights into alleviating the contradiction between poverty and watershed ecosystem protection.

3.
J Org Chem ; 89(1): 784-792, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38096498

RESUMO

A novel methodology for the synthesis of indanone derivates has been developed. The palladium-catalyzed annulation reaction of o-bromobenzaldehydes with norbornene derivatives is achieved through extremely concise reaction processes. The indanone skeleton was established directly via C-H activation of the aldehyde group under a mild reaction condition. This method is simple and practical, which simplified the traditional synthesis method for the rapid construction of indanone.

4.
J Org Chem ; 88(13): 9026-9036, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37307498

RESUMO

A concise and highly efficient synthesis method of direct esterification of aldehydes via Pd-catalyzed C-H bond activation of aldehyde group has been developed. The strategy avoids the preoxidation step of aldehyde or use of condensing agents in ester synthesis, which is not only applicable to various alcohols but also suitable for the esterification of phenolics which are usually difficult to be esterified. The methodology has the significant advantages of broad substrate scope, mild reaction conditions, and nonrequirement of additional oxidants.


Assuntos
Aldeídos , Paládio , Aldeídos/química , Paládio/química , Esterificação , Álcoois/química , Catálise
5.
Mol Cancer ; 21(1): 151, 2022 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-35864508

RESUMO

BACKGROUND: Recurrence and chemoresistance constitute the leading cause of death in colorectal cancer (CRC). Thus, it is of great significance to clarify the underlying mechanisms and identify predictors for tailoring adjuvant chemotherapy to improve the outcome of CRC. METHODS: By screening differentially expressed genes (DEGs), constructing random forest classification and ranking the importance of DEGs, we identified membrane associated guanylate kinase, WW and PDZ domain containing 3 (MAGI3) as an important gene in CRC recurrence. Immunohistochemical and western blot assays were employed to further detect MAGI3 expression in CRC tissues and cell lines. Cell counting kit-8, plate colony formation, flow cytometry, sub-cutaneous injection and azoxymethane plus dextran sulfate sodium induced mice CRC assays were employed to explore the effects of MAGI3 on proliferation, growth, cell cycle, apoptosis, xenograft formation and chemotherapy resistance of CRC. The underlying molecular mechanisms were further investigated through gene set enrichment analysis, quantitative real-time PCR, western blot, co-immunoprecipitation, ubiquitination, GST fusion protein pull-down and immunohistochemical staining assays. RESULTS: Our results showed that dysregulated low level of MAGI3 was correlated with recurrence and poor prognosis of CRC. MAGI3 was identified as a novel substrate-binding subunit of SKP1-Cullin E3 ligase to recognize c-Myc, and process c-Myc ubiquitination and degradation. Expression of MAGI3 in CRC cells inhibited cell growth, promoted apoptosis and chemosensitivity to fluoropyrimidine-based chemotherapy by suppressing activation of c-Myc in vitro and in vivo. In clinic, the stage II/III CRC patients with MAGI3-high had a significantly good recurrence-free survival (~ 80%, 5-year), and were not necessary for further adjuvant chemotherapy. The patients with MAGI3-medium had a robustly good response rate or recurrence-free survival with fluoropyrimidine-based chemotherapy, and were recommended to undergo fluoropyrimidine-based adjuvant chemotherapy. CONCLUSIONS: MAGI3 is a novel E3 ubiquitin ligase by degradation of c-Myc to regulate CRC development and may act as a potential predictor of adjuvant chemotherapy for CRC patients.


Assuntos
Neoplasias Colorretais , Ubiquitina-Proteína Ligases , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Proteínas de Membrana/genética , Camundongos , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
6.
Org Biomol Chem ; 19(46): 10210-10214, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34806101

RESUMO

Catalytic carbonyl formation ranks as one of the most important synthetic methodologies. Herein, a highly effective palladium-catalyzed and alcohol-promoted transformation of nitriles to synthesize benzocyclic ketones is described. It provides a straightforward access to potentially valuable indanone compounds in high yields in the presence of alcohol. It avoided the usage of carbon monoxide or an additional hydrolysis procedure.

7.
FEBS Open Bio ; 11(11): 3051-3062, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34510826

RESUMO

Human papillomavirus type 18 (HPV18) has high carcinogenic power in invasive cervical cancer (ICC) development. However, the underlying mechanism remains elusive. The carcinogenic properties of HPV18 require the PDZ-binding motif of its E6 oncoprotein (HPV18 E6) to degrade its target PSD95/Dlg/ZO-1 (PDZ) proteins. In this study, we demonstrated that the PDZ protein membrane-associated guanylate kinase, WW and PDZ domain containing 3 (MAGI3) inhibited the Wnt/ß-catenin pathway, and subsequently cervical cancer (CC) cell migration and invasion, via decreasing ß-catenin levels. By reducing MAGI3 protein levels, HPV18 E6 promoted CC cell migration and invasion through activation of Wnt/ß-catenin signaling. Furthermore, HPV18 rather than HPV16 was preferentially associated with the downregulation of MAGI3 and activation of the Wnt/ß-catenin pathway in CC. These findings shed light on the mechanism that gives HPV18 its high carcinogenic potential in CC progression.


Assuntos
Proteínas de Membrana/metabolismo , Neoplasias do Colo do Útero/metabolismo , Via de Sinalização Wnt/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , China , Feminino , Regulação Neoplásica da Expressão Gênica , Papillomavirus Humano 18/metabolismo , Papillomavirus Humano 18/patogenicidade , Humanos , Proteínas de Membrana/genética , Invasividade Neoplásica/genética , Proteínas Oncogênicas Virais/metabolismo , Infecções por Papillomavirus , Proteínas Repressoras/metabolismo , Fatores de Transcrição/metabolismo , Neoplasias do Colo do Útero/fisiopatologia , Via de Sinalização Wnt/genética , beta Catenina/metabolismo
8.
DNA Cell Biol ; 39(10): 1850-1861, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32790504

RESUMO

Strigolactones (SLs) are the major plant hormones that play important roles in regulating organ development and environmental stress tolerance in plants. Even though the SL-related genes have been identified and well characterized in some plants, the information of SL-related genes in soybean is not fully established yet, especially in response to salt and alkaline stresses. In this study, we identified nine SL biosynthetic genes that include two D27, two CCD7, two CCD8, and three MAX1, as well as seven SL signaling genes that comprised two D14, two MAX2, and three D53 in the soybean genome. We found that SL biosynthetic and signaling genes are evolutionary conserved among different species. Syntenic analysis of these genes revealed their location on nine chromosomes as well as the presence of 10 pairs of duplication genes. Moreover, plant hormone and stress-responsive elements were identified in the promoter regions of SL biosynthetic and signaling genes. By using reverse transcription quantitative real-time PCR, we confirmed that SL genes have different tissue expressions in roots, stems, and leaves. The expression profile of SL biosynthetic and signaling genes under salt and alkaline stresses further confirmed the regulatory roles of SL biosynthetic and signaling genes under stress. In conclusion, we identified and provided valuable information on the soybean SL biosynthetic and signaling genes, and established a foundation for further functional analysis of soybean SL-related genes in response to salt and alkaline stresses.


Assuntos
Glycine max/genética , Compostos Heterocíclicos com 3 Anéis/metabolismo , Lactonas/metabolismo , Proteínas de Plantas/genética , Estresse Salino , Cromossomos de Plantas/genética , Duplicação Gênica , Proteínas de Plantas/metabolismo , Transdução de Sinais , Glycine max/metabolismo , Sintenia
9.
PeerJ ; 8: e8457, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32071807

RESUMO

BACKGROUND: Superoxide dismutase (SOD) proteins, as one kind of the antioxidant enzymes, play critical roles in plant response to various environment stresses. Even though its functions in the oxidative stress were very well characterized, the roles of SOD family genes in regulating alkaline stress response are not fully reported. METHODS: We identified the potential family members by using Hidden Markov model and soybean genome database. The neighbor-joining phylogenetic tree and exon-intron structures were generated by using software MEGA 5.0 and GSDS online server, respectively. Furthermore, the conserved motifs were analyzed by MEME online server. The syntenic analysis was conducted using Circos-0.69. Additionally, the expression levels of soybean SOD genes under alkaline stress were identified by qRT-PCR. RESULTS: In this study, we identified 13 potential SOD genes in soybean genome. Phylogenetic analysis suggested that SOD genes could be classified into three subfamilies, including MnSODs (GmMSD1-2), FeSODs (GmFSD1-5) and Cu/ZnSODs (GmCSD1-6). We further investigated the gene structure, chromosomal locations and gene-duplication, conserved domains and promoter cis-elements of the soybean SOD genes. We also explored the expression profiles of soybean SOD genes in different tissues and alkaline, salt and cold stresses, based on the transcriptome data. In addition, we detected their expression patterns in roots and leaves by qRT-PCR under alkaline stress, and found that different SOD subfamily genes may play different roles in response to alkaline stress. These results also confirmed the hypothesis that the great evolutionary divergence may contribute to the potential functional diversity in soybean SOD genes. Taken together, we established a foundation for further functional characterization of soybean SOD genes in response to alkaline stress in the future.

10.
PLoS Comput Biol ; 15(5): e1006846, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31048911

RESUMO

The origin of avian flight is one of the most controversial debates in Paleontology. This paper investigates the wing performance of Caudipteryx, the most basal non-volant dinosaur with pennaceous feathered forelimbs by using modal effective mass theory. From a mechanical standpoint, the forced vibrations excited by hindlimb locomotion stimulate the movement of wings, creating a flapping-like motion in response. This shows that the origin of the avian flight stroke should lie in a completely natural process of active locomotion on the ground. In this regard, flapping in the history of evolution of avian flight should have already occurred when the dinosaurs were equipped with pennaceous remiges and rectrices. The forced vibrations provided the initial training for flapping the feathered wings of theropods similar to Caudipteryx.


Assuntos
Dinossauros/fisiologia , Voo Animal/fisiologia , Asas de Animais/fisiologia , Animais , Evolução Biológica , Fenômenos Biomecânicos , Aves/fisiologia , Dinossauros/anatomia & histologia , Plumas , Membro Anterior/fisiologia , Fósseis , Membro Posterior/fisiologia , Locomoção , Movimento (Física) , Filogenia , Asas de Animais/anatomia & histologia
11.
Nanoscale ; 11(14): 6719-6726, 2019 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-30900701

RESUMO

The development of nontoxic and stable all-inorganic perovskite nanocrystals (NCs) represents a major challenge to unlock widely practical applications in photoelectric fields. It is an effective strategy to discover nontoxic metal perovskite nanocrystals (NCs) with excellent optical properties. In addition, it has been proved that alkali metals such as rubidium (Rb) and potassium (K) have a good influence on improving the optical performance of perovskites. Hence, we reported new lead-free perovskite Rb7Bi3Cl16 single crystals, which displayed a zero-dimensional cluster structure and were composed of two kinds of octahedra with different distortions. At the same time, we synthesized its NCs, which showed a blue emission at 437 nm with a PLQY of 28.43% and presented a good optical and moisture stability for one month. The excellent moisture-stability might be attributed to their much higher ratio of Rb atoms and the ideal [BiCl6]3- octahedra on the surface, which are beneficial to form an inorganic BiOCl shell to protect the Rb7Bi3Cl16 NCs from moisture attack.

12.
Chem Commun (Camb) ; 52(83): 12342-12345, 2016 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-27709162

RESUMO

This study reports a host-guest interaction strategy for systematically manipulating the optical properties of cesium lead halide perovskite nanocrystals (CsPbBr3 NCs) by protectant-mediated mercapto-ß-cyclodextrin (SH-ß-CD). The fluorescence of CsPbBr3 NCs can be adjusted over 405-510 nm with the quantum yields (QY) maintained at 50-90%.

13.
Zhonghua Yan Ke Za Zhi ; 46(3): 193-6, 2010 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-20450661

RESUMO

Corneal refractive surgery, especially excimer laser corneal refractive surgery, has been used nearly 20 years in China. As the development of high technology and the change of life style, people who received refractive surgery not only demands good visual acuity but also good visual quality. In recent years, more and more new techniques and equipments have sprung up in this field. Therefore, this provides more approaches for surgeon to design the surgical plan and meet patients' needs to see clearly and comfortably. In this article, the author minutely dissects the importance and influence of the design procedure from the perspective of scotopic vision (such as; design of thin cornea, severe astigmatism, scotopic large pupil size, and special corneal shape) and personalized surgical parameters.


Assuntos
Córnea/cirurgia , Miopia/cirurgia , Procedimentos Cirúrgicos Refrativos , Humanos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA