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1.
Chembiochem ; 24(1): e202200339, 2023 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-36250581

RESUMO

Enzymes are effective biological catalysts that accelerate almost all metabolic reactions in living organisms. Synthetic modulators of enzymes are useful tools for the study of enzymatic reactions and can provide starting points for the design of new drugs. Here, we report on the discovery of a class of biologically active compounds that covalently modifies lysine residues in human liver pyruvate kinase (PKL), leading to allosteric activation of the enzyme (EC50 =0.29 µM). Surprisingly, the allosteric activation control point resides on the lysine residue K282 present in the catalytic site of PKL. These findings were confirmed by structural data, MS/MS experiments, and molecular modelling studies. Altogether, our study provides a molecular basis for the activation mechanism and establishes a framework for further development of human liver pyruvate kinase covalent activators.


Assuntos
Lisina , Piruvato Quinase , Humanos , Piruvato Quinase/química , Piruvato Quinase/metabolismo , Espectrometria de Massas em Tandem , Fígado , Domínio Catalítico , Regulação Alostérica
2.
J Transl Med ; 18(1): 436, 2020 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-33198777

RESUMO

BACKGROUND: Squamous cell carcinoma (SCC) is a main pathological type of non-small cell lung cancer. It is common among elderly patients with poor prognosis. We aimed to establish an accurate nomogram to predict survival for elderly patients (≥ 60 years old) with SCC based on the Surveillance, Epidemiology, and End Results (SEER) database. METHODS: The gerontal patients diagnosed with SCC from 2010 to 2015 were collected from the Surveillance, Epidemiology, and End Results (SEER) database. The independent prognostic factors were identified using multivariate Cox proportional hazards regression analysis, which were utilized to conduct a nomogram for predicting survival. The novel nomogram was evaluated by Concordance index (C-index), calibration curves, net reclassification improvement (NRI), integrated discrimination improvement (IDI), and decision curve analysis (DCA). RESULTS: 32,474 elderly SCC patients were included in the analysis, who were randomly assigned to training cohort (n = 22,732) and validation cohort (n = 9742). The following factors were contained in the final prognostic model: age, sex, race, marital status, tumor site, AJCC stage, surgery, radiation and chemotherapy. Compared to AJCC stage, the novel nomogram exhibited better performance: C-index (training group: 0.789 vs. 0.730, validation group: 0.791 vs. 0.733), the areas under the receiver operating characteristic curve of the training set (1-year AUC: 0.846 vs. 0.791, 3-year AUC: 0.860 vs. 0.801, 5-year AUC: 0.859 vs. 0.794) and the validation set (1-year AUC: 0.846 vs. 0.793, 3-year AUC: 0.863 vs. 0.806, 5-year AUC: 0.866 vs. 0.801), and the 1-, 3- and 5-year calibration plots. Additionally, the NRI and IDI and 1-, 3- and 5-year DCA curves all confirmed that the nomogram was a great prognosis tool. CONCLUSIONS: We constructed a novel nomogram that could be practical and helpful for precise evaluation of elderly SCC patient prognosis, thus helping clinicians in determining the appropriate therapy strategies for individual SCC patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Carcinoma de Células Escamosas , Neoplasias Pulmonares , Idoso , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/epidemiologia , Pessoa de Meia-Idade , Prognóstico , Programa de SEER
3.
Int Orthop ; 42(1): 125-132, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29116357

RESUMO

PURPOSE: Poly(methyl methacrylate) (PMMA) cement is widely used for percutaneous kyphoplasty and vertebroplasty (PKP and PVP) but possesses formidable shortcomings due to non-degradability. Here, a biodegradable replacement is developed. METHODS: Calcium phosphate cement (CPC) was redesigned by incorporating starch and BaSO4 (new cement named as CPB). The biomechanical, biocompatibility, osseointegrative and handling properties of CPB were systematically evaluated in vitro and in vivo by the models of osteoporotic sheep vertebra, rat subcutaneous implantation and rat femoral defect. RESULTS: CPB revealed appropriate injectability and setting ability for PKP and PVP. More importantly, its biomechanical strengths measured by in vitro and in vivo models were not less than that of PMMA, while its biodegradability and osseointegrative capacities were significantly enhanced compared to PMMA. CONCLUSIONS: CPB is injectable, biomechanically robust, biodegradable and osseointegrative, demonstrating revolutionary potential for the application in PKP and PVP.


Assuntos
Cimentos Ósseos/química , Fosfatos de Cálcio/farmacologia , Cifoplastia/instrumentação , Fraturas da Coluna Vertebral/cirurgia , Vertebroplastia/instrumentação , Implantes Absorvíveis/efeitos adversos , Animais , Fenômenos Biomecânicos , Cimentos Ósseos/farmacologia , Fêmur/cirurgia , Fraturas por Compressão/cirurgia , Humanos , Cifoplastia/métodos , Masculino , Osseointegração , Osteoporose/cirurgia , Polimetil Metacrilato/farmacologia , Ratos , Ratos Sprague-Dawley , Ovinos , Coluna Vertebral/cirurgia , Vertebroplastia/métodos
4.
Phys Chem Chem Phys ; 18(12): 8673-81, 2016 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-26950000

RESUMO

Mutations in the rearranged during transfection (RET) tyrosine kinase gene leading to gain or loss of function have been associated with the development of several human cancers and Hirschsprung's disease (HSCR). However, to what extent these mutations affect individual bio-molecular functions remains unclear. In this article, the functionally significant mutations in the RET CLD1-4 calcium-binding site which lead to HSCR, and depletion of calcium ions in the RET CLD1-4 calcium binding site, were investigated by molecular dynamics simulations--to understand the mechanistic action of the mutations or loss of calcium ions in altering the protein kinase structure, dynamics, and stability. The mutations or loss of calcium ions change the local conformation and change the free energy landscape. Specifically, the mutations and loss of calcium ions decrease the radius of gyration of the whole structure, leading to improper protein folding and GFL-GFRα contact site reduction. Furthermore, based on the most populated conformation in the wildtype MD simulations, a pharmacophore was generated by fragment docking to identify key features of the possible inhibitors targeting the calcium binding site. Overall, the findings may provide useful structural insights into the molecular mechanism underlying RET calcium-binding site mutations and assist in development of novel drugs targeting the extracellular ligand contact site of wildtype RET.


Assuntos
Caderinas/química , Cálcio/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Sítios de Ligação , Caderinas/metabolismo , Análise por Conglomerados , Doença de Hirschsprung/metabolismo , Doença de Hirschsprung/patologia , Humanos , Simulação de Dinâmica Molecular , Mutação , Análise de Componente Principal , Estrutura Terciária de Proteína , Receptores Proteína Tirosina Quinases/química , Receptores Proteína Tirosina Quinases/genética , Termodinâmica
5.
J Biomed Mater Res B Appl Biomater ; 112(1): e35316, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37578036

RESUMO

As potential alternatives for calcium phosphate bone cements, magnesium phosphate bone cements (MPC) have attracted considerable attention in recent years. However, their several defects, such as rapid setting times, highly hydration temperature and alkaline pH due to the part of the unreacted phosphate, restricted their applications in human body. With aim to overcome these defects, a novel polypeptite poly(γ-glutamic acid) (γ-PGA) modified MPC were developed. Effect of γ-PGA content on the injectability, anti-washout ability, setting times, hydration temperature, mechanical compressive strength, in vitro bioactivity and degradation were investigated. Moreover, in vitro cyto-compatibility was evaluated using MC3T3-E1 cells by CCK-8 and Live/Dead staining. All these results indicated that the 10%PGA-MPC with an improved handling performances, low hydration temperature, high mechanical compressive strength, and good cyto-compatibility hold a great potential for bone repair and regeneration.


Assuntos
Cimentos Ósseos , Compostos de Magnésio , Fosfatos , Ácido Poliglutâmico/análogos & derivados , Humanos , Cimentos Ósseos/farmacologia , Cimentos Ósseos/química , Teste de Materiais , Fosfatos/química , Fosfatos de Cálcio/química , Regeneração Óssea , Força Compressiva
6.
Int J Biol Macromol ; 239: 124208, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36972827

RESUMO

In this study, to increase the accumulation of MTX in the tumor site and reduce the toxicity to normal tissues by MA, a novel nano-drug delivery system comprised of hyaluronic acid (HA)-mangiferin (MA)-methotrexate (MTX) (HA-MA-MTX) was developed by a self-assembly strategy. The advantage of the nano-drug delivery system is that MTX can be used as a tumor-targeting ligand of the folate receptor (FA), HA can be used as another tumor-targeting ligand of the CD44 receptor, and MA serves as an anti-inflammatory agent. 1HNMR and FT-IR results confirmed that HA, MA, and MTX were well coupled together by the ester bond. DLS and AFM images revealed that the size of HA-MA-MTX nanoparticles was about ~138 nm. In vitro cell experiments proved that HA-MA-MTX nanoparticles have a positive effect on inhibiting K7 cancer cells while having relatively lower toxicity to normal MC3T3-E1 cells than MTX does. All these results indicated that the prepared HA-MA-MTX nanoparticles can be selectively ingested by K7 tumor cells through FA and CD44 receptor-mediated endocytosis, thus inhibiting the growth of tumor tissues and reducing the nonspecific uptake toxicity caused by chemotherapy. Therefore, these self-assembled HA-MA-MTX NPs could be a potential anti-tumor drug delivery system.


Assuntos
Nanopartículas , Neoplasias , Humanos , Metotrexato/química , Ácido Hialurônico/química , Sistemas de Liberação de Fármacos por Nanopartículas , Ligantes , Espectroscopia de Infravermelho com Transformada de Fourier , Neoplasias/tratamento farmacológico , Nanopartículas/uso terapêutico , Nanopartículas/química , Sistemas de Liberação de Medicamentos/métodos , Linhagem Celular Tumoral
7.
ACS Appl Mater Interfaces ; 15(13): 17175-17187, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36946494

RESUMO

The wild environment is unpredictable where soaring or plummeting temperatures in extreme weather events can pose serious threats to human lives. Incorporating passive evaporative cooling and controllable electric heating into clothing could effectively protect human beings from such harsh environments. In this work, poly(3,4-ethylene dioxy thiophene):poly(styrene sulfonate)/poly(ethylene glycol) (PPP) fibers with the core-shell structure and attractively textured surface have been successfully prepared via a single-nozzle wet-spinning technique. Results show that the fibers possess fascinating specific surface area (184.8 m2·g-1), electrical conductivity (50 S·cm-1), and stretchability (>100%) because of the novel preparation method and hierarchical morphological design. Through simple textile manufacturing routes, PPP fibers can be woven into fabrics easily, which exhibit desirable breathability, washability, and mechanical strength for smart textiles while maintaining favorable hygroscopicity. Benefiting from the textured structure with large specific surface area, PPP fabric exhibits attractile evaporative cooling rate. Practical application tests have demonstrated that under direct sunlight, the surface temperature of the PPP fabric is ∼5.2 and ∼10.8 °C lower than commercial cotton and polyester fabrics, respectively. Meanwhile, as conductive fibers, the resultant PPP fabric can heat under low-power electricity, therefore achieving the effect of "warmth in winter and coolness in summer". The facile fabrication process and elevated performance of PPP fibers present significant advantages for applications in intelligent garments and textiles, as well as comprehensive personal thermal management, which opens a new avenue for future design in these fields.

8.
Ying Yong Sheng Tai Xue Bao ; 33(11): 3097-3104, 2022 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-36384844

RESUMO

Decapterus maruadsi is an important economic pelagic fish in the southern coastal area of Zhejiang. According to the bottom trawl surveys conducted in May, August, November 2020 and January 2021, the feeding habits of D. maruadsi in the southern coastal area of Zhejiang were examined by both stable isotope (carbon, δ13C, and nitrogen, δ15N) and stomach content analyses. Results showed that the δ13C value of D. maruadsi ranged from -17.76‰ to -15.25‰, with a mean of (-16.55±0.60)‰, while the δ15N value ranged from 9.06‰ and 13.03‰, with a mean of (11.76±0.88)‰. There was a significant negative correlation between the δ13C values and fork length, and a positive relationship between the δ15N with fork length. Results from stomach content analysis showed that the main prey groups of D. maruadsi were fish, shrimp, crabs, Cephalopod, Polychaete, and small crustaceans. As for the stable isotope analysis, the nutritional contribution rate of shrimp was the highest (40%-84%) among all prey groups, followed by Polychaete, small crustaceans, crabs, Cephalopods and fish. Significant ontogenetic dietary changes were found for D. maruadsi. As the fork length of D. maruadsi increased, it tended to eat prey from higher trophic levels.


Assuntos
Ecologia , Conteúdo Gastrointestinal , Animais , Peixes , Isótopos , Crustáceos
9.
Eur J Med Chem ; 234: 114226, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35305461

RESUMO

REarranged during Transfection (RET) is a transmembrane receptor tyrosine kinase that is required for development of multiple human tissues, but which is also an important contributor to human cancers. RET activation through rearrangement or point mutations occurs in thyroid and lung cancers. Furthermore, activation of wild type RET is an increasingly recognized mechanism promoting tumor growth and dissemination of a much broader group of cancers. RET is therefore an attractive therapeutic target for small-molecule kinase inhibitors. Non-invasive control of RET signaling with light offers the promise of unveiling its complex spatiotemporal dynamics in vivo. In this work, photoswitchable DFG-out RET kinase inhibitors based on heterocycle-derived azobenzenes were developed, enabling photonic control of RET activity. Based on the binding mode of DFG-out kinase inhibitors and using RET kinase as the test model, we developed a photoswitchable inhibitor with a quinoline "head" constituting the azoheteroarene. This azo compound was further modified by three different strategies to increase the difference in biological activity between the E-isomer and the light enriched Z-isomer. Stilbene-based derivatives were used as model compounds to guide in the selection of substituents that could eventually be introduced to the corresponding azo compounds. The most promising quinoline-based compound showed more than a 15-fold difference in bioactivity between the two isomers in a biochemical assay. However, the same compound showed a decreased Z/E (IC50) ratio in the cellular assay, tentatively assigned to stability issues. The corresponding stilbene compound gave a Z/E (IC50) ratio well above 100, consistent with that measured in the biochemical assay. Ultimately, a 7-azaindole based photoswitchable DFG-out kinase inhibitor was shown to display more than a 10-fold difference in bioactivity between the two isomers, in both a biochemical and a cell-based assay, as well as excellent stability even under reducing conditions.


Assuntos
Antineoplásicos , Neoplasias Pulmonares , Estilbenos , Antineoplásicos/farmacologia , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Inibidores de Proteínas Quinases/química , Proteínas Proto-Oncogênicas c-ret , Receptores Proteína Tirosina Quinases
10.
Eur J Med Chem ; 234: 114270, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35290845

RESUMO

Liver pyruvate kinase (PKL) is a major regulator of metabolic flux and ATP production during liver cell glycolysis and is considered a potential drug target for the treatment of non-alcoholic fatty liver disease (NAFLD). In this study, we report the first ADP-competitive PKL inhibitors and identify several starting points for the further optimization of these inhibitors. Modeling and structural biology guided the optimization of a PKL-specific anthraquinone-based compound. A structure-activity relationship study of 47 novel synthetic derivatives revealed PKL inhibitors with half-maximal inhibitory concentration (IC50) values in the 200 nM range. Despite the difficulty involved in studying a binding site as exposed as the ADP site, these derivatives feature expanded structural diversity and chemical spaces that may be used to improve their inhibitory activities against PKL. The obtained results expand the knowledge of the structural requirements for interactions with the ADP-binding site of PKL.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Piruvato Quinase , Difosfato de Adenosina/farmacologia , Antraquinonas/farmacologia , Humanos , Fígado/metabolismo , Piruvato Quinase/metabolismo
11.
Int J Biol Macromol ; 166: 71-79, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33091477

RESUMO

As an anti-metabolic drug, methotrexate (MTX) plays an important role in the treatment of various malignant tumors. However, several side effects such as low selectivity and high toxic of MTX limited its further applications. With aims to increase its accumulation in the tumor sites and reduce the toxicity of normal tissue nonspecific uptake, a self-assembled hyaluronic acid-alendronate-methotrexate nanoparticle (HA-ALN-MTX NPs) with a dual-tumor-targeted drug loaded system was designed and synthesized with an average particle size of 265.6 ± 13.3 nm. The advantage of this nanosystem is that the anticancer drug MTX can be used as a tumor-targeted ligand for folate acid receptors (FA), and hyaluronic acid (HA) can be used as another tumor targeted ligand for CD44 receptors. In vitro experiments confirmed that HA-ALN-MTX NPs has lower toxic effect on normal tissue cells HUVECs and has relatively high proliferation inhibition effect on tumor cells A549. Moreover, the inhibition effect could be adjusted by altering the dose of given drugs. All these results revealed that the prepared HA-ALN-MTX NPs could be selectively taken up by tumor cells by FA and CD44 receptor-mediated endocytosis. Therefore, self-assembled HA-ALN-MTX NPs targeted by these FA/CD44 receptors for anticancer drugs could act as effective antitumor drugs.


Assuntos
Alendronato/química , Antimetabólitos Antineoplásicos/administração & dosagem , Ácido Hialurônico/química , Metotrexato/administração & dosagem , Nanopartículas/química , Células A549 , Antimetabólitos Antineoplásicos/farmacologia , Proliferação de Células , Endocitose , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/fisiologia , Humanos , Metotrexato/farmacologia
12.
Ying Yong Sheng Tai Xue Bao ; 32(1): 333-341, 2021 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-33477242

RESUMO

The variations of life history traits have been observed for many fish species, which gains much concerns in the study of aquatic biology and ecology. In this study, the biological characteristics were explored for yellow croaker (Larimichthys polyactis) in the offshore waters of southern Zhejiang, based on 4920 individuals collected from 13 fishery-independent seasonal surveys from autumn 2015 to autumn 2018. Linear mixed effects models were used to estimate the growth, maturity characteristics, and their heterogeneity. The body length of yellow croaker samples ranged from 13 to 215 mm with the dominant body of 110 to 154 mm. The body weight ranged from 0.5 to 182.2 g, with the dominant body weight from 20 to 55 g. The results showed that the linear mixed effects models with random effects from season, gender, and year performed best for length-weight relationship, with the lowest AIC and RMSE values. The effects of season were much larger than those of genders and years. When the length exceeded 160 mm, the weight gain rate of yellow croaker was faster in spring and summer, lower in autumn and winter, while the male individuals gained more weight than the females with the same body length. Among 4841 individuals of specimens with gonadal data, the individuals at maturity Ⅱ stage occupied 50.4%, and the individuals at maturity stage contributed to 19.6%. The results from the best linear mixed effects model showed that season had the most significant influence on the maturity of yellow croaker. The 50% maturity length (L50%) was much lower in winter (124.6 mm) with no much difference between other seasons, indicating that yellow croaker matures earlier in winter. Our results indicated that linear mixed effect model could reflect the biological heterogeneity of yellow croaker conveniently and that the growth and maturity of yellow croaker had significantly sexual and temporal variations, which should be considered in the stock assessment and fishery management for yellow croaker.


Assuntos
Perciformes , Animais , China , Feminino , Pesqueiros , Peixes , Humanos , Modelos Lineares , Masculino
13.
Int J Bioprint ; 7(4): 418, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34805597

RESUMO

In this study, porous polylactic acid/methotrexate (PLA/MTX) scaffolds were successfully fabricated by three-dimensional (3D) printing technology as controllable drug delivery devices to suppress tumor growth. Scanning electron microscopy and energy-dispersive spectrometer confirmed that MTX drug was successfully incorporated into the PLA filament. 3D-printed PLA/MTX scaffolds allow sustained release of drug molecules in vitro for more than 30 days, reducing systemic toxic side effects caused by injection or oral administration. In vitro cytotoxicity assay revealed that PLA/MTX scaffolds have a relatively high inhibitory effect on the tumor cells (MG-63, A549, MCF-7, and 4T1) and relatively low toxic effect on the normal MC3T3-E1 cells. Furthermore, results of in vivo experiments confirmed that PLA/MTX scaffolds highly suppressed tumor growth and no obvious side effects on the organs. All these results suggested that 3D-printed PLA/MTX scaffolds could be used as controllable drug delivery systems for tumor suppression.

14.
Chem Commun (Camb) ; 57(78): 10043-10046, 2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34505602

RESUMO

We report the synthesis and characterisation of a photoswitchable DFG-out kinase inhibitor. Photocontrol of the target kinase in both enzymatic and living cell assays is demonstrated.


Assuntos
Compostos Azo/farmacologia , Desenvolvimento de Medicamentos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Quinases/metabolismo , Compostos Azo/química , Células HEK293 , Humanos , Estrutura Molecular , Inibidores de Proteínas Quinases/química
15.
Environ Sci Pollut Res Int ; 28(34): 46827-46837, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33742385

RESUMO

To effectively use the fishery count data containing zero values, Setipinna taty in the coastal waters of south inshore of Zhejiang in China from 2017 to 2019 was used in this study. Environmental factors, such as water temperature, water depth, and salinity, were selected to establish models and compare based on the generalized additive model (GAM) of the Tweedie distribution (Tweedie-GAM) and two-stage GAM, Ad hoc method, and generalized additive mixed model (GAMM). The results showed that each station accounted for a higher proportion of zero values and the two-stage GAM model had a higher deviation interpretation rate, and GAM I and GAM II had 19.6% and 60.4% deviation interpretation rates. The cross-validation results showed that the performance evaluation of the two-stage GAM model was the best and showed the highest R2 value, the lowest average absolute error, and the relatively small root mean square error. This study found that the abundance of S. taty in the south inshore of Zhejiang was highest at around 21°C and 18°C in spring and autumn, and the abundance reached the highest at a water depth of about 20 m. In spatial distribution, the high value of the abundance of S. taty was mostly distributed in the coastal waters in the south of 28°N. In future research, models should be fitted and compared for different sampling zero-value ratios, and more environmental factors should be included to accurately find an optimal model and provide references for the conservation of fishery resources.


Assuntos
Pesqueiros , Peixes , Animais , China , Salinidade , Estações do Ano , Temperatura
16.
Cancers (Basel) ; 13(2)2021 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-33478099

RESUMO

Pyruvate kinase muscle type (PKM) is a key enzyme in glycolysis and plays an important oncological role in cancer. However, the association of PKM expression and the survival outcome of patients with different cancers is controversial. We employed systems biology methods to reveal prognostic value and potential biological functions of PKM transcripts in different human cancers. Protein products of transcripts were shown and detected by western blot and mass spectrometry analysis. We focused on different transcripts of PKM and investigated the associations between their mRNA expression and the clinical survival of the patients in 25 different cancers. We find that the transcripts encoding PKM2 and three previously unstudied transcripts, namely ENST00000389093, ENST00000568883, and ENST00000561609, exhibited opposite prognostic indications in different cancers. Moreover, we validated the prognostic effect of these transcripts in an independent kidney cancer cohort. Finally, we revealed that ENST00000389093 and ENST00000568883 possess pyruvate kinase enzymatic activity and may have functional roles in metabolism, cell invasion, and hypoxia response in cancer cells. Our study provided a potential explanation to the controversial prognostic indication of PKM, and could invoke future studies focusing on revealing the biological and oncological roles of these alternative spliced variants of PKM.

17.
Environ Sci Pollut Res Int ; 27(20): 25461-25474, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32350839

RESUMO

The present study used multivariate techniques, to analyze the fish species diversity and distribution patterns in order to determine the possible role of environmental parameters as drivers of fish community structure and composition in the Yangtze River Estuary (YRE). This analysis was conducted using data obtained in the YRE from February 2012 to December 2014. Analysis of the catch data showed that species composition, total density, and total biomass varied significantly between stations and seasons. Thirty-eight species belonging to 18 families were collected. Sciaenidae was the most dominant family accounting for 40.8% of total captured specimens. In descending order, Collichthys lucidus, Cynoglossus gracilis, Chaeturichthys stigmatias, and Lophiogobius ocellicauda dominated catches in the YRE. These four species constituted 64.2% of the total catches and showed average dissimilarities of 74.19% between stations and 81.3% between months. The highest number of fish specimens captured was recorded in August 2012 while the highest species richness was observed in December 2013. The mean fish density and biomass for the YRE was 0.35 individuals/m2 and 2.5 g/m2, respectively. The mean density and biomass for the most important and dominant species changed significantly between stations and seasons. Canonical correspondence analysis indicated that salinity and chlorophyll-a were the key variables that structured the fish assemblage in the YRE. High total species density and biomass were recorded in high saline stations (North Branch) of the YRE. This study confirms that most species captured in the YRE needs estuarine conditions to complete their growth and development. Hence, the findings in this study are important to understanding and developing suitable conservation plans for the management of fish resources in the YRE.


Assuntos
Estuários , Rios , Animais , Biomassa , Ecossistema , Peixes , Estações do Ano
18.
Mater Sci Eng C Mater Biol Appl ; 116: 110904, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32806278

RESUMO

Kyphoplasty is an effective minimally invasive surgical treatment of osteoporotic vertebral compression fractures. Current problems associated with kyphoplasty require better injectable bone cements with improved biodegradability and osseointegrative property as an alternative to polymethyl methacrylate (PMMA) bone cement. Calcium phosphate cements (CPCs) possess superior biodegradability and osteoconductivity but inferior injectability and mechanical strengths, rendering them unsuitable for kyphoplasty applications. Our previous studies developed a corn starch-reinforced CPC with improved handling, injectable and mechanical properties, yet for kyphoplasty applications the reinforced CPC needs to have radiopacity and further enhanced mechanical strength. This work therefore developed a CPC-Starch-BaSO4 (CSB) system and investigated the effects of radiopaque agent BaSO4 on injectability, radiopacity, mechanical and biocompatibility properties of the system. Results showed that the addition of BaSO4 significantly improved radiopacity and mechanical strengths of CPC cement. In addition, in vitro evaluations including apoptosis, hemolysis and endotoxin tests and in vivo evaluation of subcutaneous implantation all revealed that CSB was biocompatible. This study demonstrates that CSB could meet the clinical requirements for minimally invasive surgery and thus have great potential for kyphoplasty applications.


Assuntos
Fraturas por Compressão , Cifoplastia , Fraturas da Coluna Vertebral , Cimentos Ósseos/farmacologia , Fosfatos de Cálcio/farmacologia , Humanos , Polimetil Metacrilato
19.
Elife ; 92020 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-32662770

RESUMO

Peroxiredoxins are H2O2 scavenging enzymes that also carry out H2O2 signaling and chaperone functions. In yeast, the major cytosolic peroxiredoxin, Tsa1 is required for both promoting resistance to H2O2 and extending lifespan upon caloric restriction. We show here that Tsa1 effects both these functions not by scavenging H2O2, but by repressing the nutrient signaling Ras-cAMP-PKA pathway at the level of the protein kinase A (PKA) enzyme. Tsa1 stimulates sulfenylation of cysteines in the PKA catalytic subunit by H2O2 and a significant proportion of the catalytic subunits are glutathionylated on two cysteine residues. Redox modification of the conserved Cys243 inhibits the phosphorylation of a conserved Thr241 in the kinase activation loop and enzyme activity, and preventing Thr241 phosphorylation can overcome the H2O2 sensitivity of Tsa1-deficient cells. Results support a model of aging where nutrient signaling pathways constitute hubs integrating information from multiple aging-related conduits, including a peroxiredoxin-dependent response to H2O2.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Peróxido de Hidrogênio/metabolismo , Peroxidases/genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Longevidade , Oxirredução , Peroxidases/metabolismo , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo
20.
Cancer Manag Res ; 12: 1947-1958, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32214852

RESUMO

OBJECTIVE: The disease complexity of metastatic non-small-cell lung cancer (mNSCLC) makes it difficult for physicians to make clinical decisions efficiently and accurately. The Watson for Oncology (WFO) system of artificial intelligence might help physicians by providing fast and precise treatment regimens. This study measured the concordance of the medical treatment regimens of the WFO system and actual clinical regimens, with the aim of determining the suitability of WFO recommendations for Chinese patients with mNSCLC. METHODS: Retrospective data of mNSCLC patients were input to the WFO, which generated a treatment regimen (WFO regimen). The actual regimen was made by physicians in a medical team for patients (medical-team regimen). The factors influencing the consistency of the two treatment options were analyzed by univariate and multivariate analyses. RESULTS: The concordance rate was 85.16% between the WFO and medical-team regimens for mNSCLC patients. Logistic regression showed that the concordance differed significantly for various pathological types and gene mutations in two treatment regimens. Patients with adenocarcinoma had a lower rate of "recommended" regimen than those with squamous cell carcinoma. There was a statistically significant difference in EGFR-mutant patients for "not recommended" regimens with inconsistency rate of 18.75%. In conclusion, the WFO regimen has 85.16% consistency rate with medical-team regimen in our treatment center. The different pathological type and different gene mutation markedly influenced the agreement rate of the two treatment regimens. CONCLUSION: WFO recommendations have high applicability to mNSCLC patients in our hospital. This study demonstrates that the valuable WFO system may assist the doctors better to determine the accurate and effective treatment regimens for mNSCLC patients in the Chinese medical setting.

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