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1.
Adv Exp Med Biol ; 1414: 1-26, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35708844

RESUMO

Three human nucleases, SNM1A, SNM1B/Apollo, and SNM1C/Artemis, belong to the SNM1 gene family. These nucleases are involved in various cellular functions, including homologous recombination, nonhomologous end-joining, cell cycle regulation, and telomere maintenance. These three proteins share a similar catalytic domain, which is characterized as a fused metallo-ß-lactamase and a CPSF-Artemis-SNM1-PSO2 domain. SNM1A and SNM1B/Apollo are exonucleases, whereas SNM1C/Artemis is an endonuclease. This review contains a summary of recent research on SNM1's cellular and biochemical functions, as well as structural biology studies. In addition, protein structure prediction by the artificial intelligence program AlphaFold provides a different view of the proteins' non-catalytic domain features, which may be used in combination with current results from X-ray crystallography and cryo-EM to understand their mechanism more clearly.


Assuntos
Enzimas Reparadoras do DNA , Reparo do DNA , Humanos , Inteligência Artificial , Enzimas Reparadoras do DNA/genética , Enzimas Reparadoras do DNA/metabolismo , Endonucleases/genética , Endonucleases/metabolismo , Exodesoxirribonucleases/genética , Exodesoxirribonucleases/metabolismo , Proteínas Nucleares/metabolismo , Proteínas de Ciclo Celular/metabolismo
2.
J Biol Chem ; 295(35): 12368-12377, 2020 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-32576658

RESUMO

The endonuclease Artemis is responsible for opening DNA hairpins during V(D)J recombination and for processing a subset of pathological DNA double-strand breaks. Artemis is an attractive target for the development of therapeutics to manage various B cell and T cell tumors, because failure to open DNA hairpins and accumulation of chromosomal breaks may reduce the proliferation and viability of pre-T and pre-B cell derivatives. However, structure-based drug discovery of specific Artemis inhibitors has been hampered by a lack of crystal structures. Here, we report the structure of the catalytic domain of recombinant human Artemis. The catalytic domain displayed a polypeptide fold similar overall to those of other members in the DNA cross-link repair gene SNM1 family and in mRNA 3'-end-processing endonuclease CPSF-73, containing metallo-ß-lactamase and ß-CASP domains and a cluster of conserved histidine and aspartate residues capable of binding two metal atoms in the catalytic site. As in SNM1A, only one zinc ion was located in the Artemis active site. However, Artemis displayed several unique features. Unlike in other members of this enzyme class, a second zinc ion was present in the ß-CASP domain that leads to structural reorientation of the putative DNA-binding surface and extends the substrate-binding pocket to a new pocket, pocket III. Moreover, the substrate-binding surface exhibited a dominant and extensive positive charge distribution compared with that in the structures of SNM1A and SNM1B, presumably because of the structurally distinct DNA substrate of Artemis. The structural features identified here may provide opportunities for designing selective Artemis inhibitors.


Assuntos
Endonucleases/química , Dobramento de Proteína , Zinco/química , Animais , Domínio Catalítico , Proteínas de Ligação a DNA , Endonucleases/genética , Humanos , Células Sf9 , Spodoptera , Relação Estrutura-Atividade
3.
Int J Mol Sci ; 22(19)2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34638520

RESUMO

Biomarkers are essential tools in osteoarthritis (OA) research, clinical trials, and drug development. Detecting and evaluating biomarkers in OA research can open new avenues for researching and developing new therapeutics. In the present report, we have explored the serological detection of various osteoarthritis-related biomarkers in the preclinical model of OA. In this surgical OA model, we disrupted the medial tibial cartilage's integrity via anterior cruciate ligament transection combined with medial meniscectomy (ACLT+MMx) of a single joint of Wistar rats. The progression of OA was verified, as shown by the microscopic deterioration of cartilage and the increasing cartilage degeneration scoring from 4 to 12 weeks postsurgery. The concentration of serological biomarkers was measured at two timepoints, along with the complete blood count and bone electrolytes, with biochemical analysis further conducted. The panel evaluated inflammatory biomarkers, bone/cartilage biomarkers, and lipid metabolic pathway biomarkers. In chronic OA rats, we found a significant reduction of total vitamin D3 and C-telopeptide fragments of type II (CTX-II) levels in the serum as compared to sham-operated rats. In contrast, the serological levels of adiponectin, leptin, and matrix metallopeptidase (MMP3) were significantly enhanced in chronic OA rats. The inflammatory markers, blood cell composition, and biochemical profile remained unchanged after surgery. In conclusion, we found that a preclinical model of single-joint OA with significant deterioration of the cartilage can lead to serological changes to the cartilage and metabolic-related biomarkers without alteration of the systemic blood and biochemical profile. Thus, this biomarker profile provides a new tool for diagnostic/therapeutic assessment in OA scientific research.


Assuntos
Lesões do Ligamento Cruzado Anterior/patologia , Ligamento Cruzado Anterior/patologia , Colecalciferol/sangue , Metaloproteinase 3 da Matriz/sangue , Osteoartrite/diagnóstico , Adiponectina/sangue , Animais , Ligamento Cruzado Anterior/cirurgia , Biomarcadores/sangue , Cartilagem Articular/patologia , Colágeno Tipo II/sangue , Modelos Animais de Doenças , Leptina/sangue , Meniscectomia , Meniscos Tibiais/cirurgia , Osteoartrite/sangue , Osteoartrite/patologia , Fragmentos de Peptídeos/sangue , Ratos , Ratos Wistar , Tíbia/patologia
4.
J Neuroinflammation ; 17(1): 202, 2020 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-32631435

RESUMO

BACKGROUND: Spinal cord injury (SCI) triggers the primary mechanical injury and secondary inflammation-mediated injury. Neuroinflammation-mediated insult causes secondary and extensive neurological damage after SCI. Microglia play a pivotal role in the initiation and progression of post-SCI neuroinflammation. METHODS: To elucidate the significance of LRCH1 to microglial functions, we applied lentivirus-induced LRCH1 knockdown in primary microglia culture and tested the role of LRCH1 in microglia-mediated inflammatory reaction both in vitro and in a rat SCI model. RESULTS: We found that LRCH1 was downregulated in microglia after traumatic SCI. LRCH1 knockdown increased the production of pro-inflammatory cytokines such as IL-1ß, TNF-α, and IL-6 after in vitro priming with lipopolysaccharide and adenosine triphosphate. Furthermore, LRCH1 knockdown promoted the priming-induced microglial polarization towards the pro-inflammatory inducible nitric oxide synthase (iNOS)-expressing microglia. LRCH1 knockdown also enhanced microglia-mediated N27 neuron death after priming. Further analysis revealed that LRCH1 knockdown increased priming-induced activation of p38 mitogen-activated protein kinase (MAPK) and Erk1/2 signaling, which are crucial to the inflammatory response of microglia. When LRCH1-knockdown microglia were adoptively injected into rat spinal cords, they enhanced post-SCI production of pro-inflammatory cytokines, increased SCI-induced recruitment of leukocytes, aggravated SCI-induced tissue damage and neuronal death, and worsened the locomotor function. CONCLUSION: Our study reveals for the first time that LRCH1 serves as a negative regulator of microglia-mediated neuroinflammation after SCI and provides clues for developing novel therapeutic approaches against SCI.


Assuntos
Mediadores da Inflamação/metabolismo , Proteínas dos Microfilamentos/antagonistas & inibidores , Proteínas dos Microfilamentos/metabolismo , Microglia/metabolismo , Traumatismos da Medula Espinal/metabolismo , Animais , Células Cultivadas , Inflamação/induzido quimicamente , Inflamação/metabolismo , Inflamação/patologia , Lipopolissacarídeos/toxicidade , Masculino , Microglia/efeitos dos fármacos , Microglia/patologia , Ratos , Ratos Sprague-Dawley , Traumatismos da Medula Espinal/patologia
5.
J Org Chem ; 84(4): 2366-2371, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30676019

RESUMO

This paper reports the tandem reaction strategy of the Passerini/Staudinger/aza-Wittig reaction based on the in situ capture of isocyanides. According to this strategy, isocyanides are synthesized in situ and immediately work as the substrate for the Passerini reaction and postmodification tandem reaction in one pot. In addition, two types of new compounds, 5-oxo-3,5-dihydrobenzo[ e][1,4]oxazepines and 6-oxo-5,6-dihydro-2 H-1,4-oxazines, were synthesized using the tandem reaction strategy that includes five-step transformations in one pot.

6.
Analyst ; 144(10): 3436-3441, 2019 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-31020297

RESUMO

Organophosphorus pesticides (OPs) are widely used in agricultural fields, but exhibit high toxicity to human beings. A sensitive fluorescence assay for organophosphorus pesticides was developed using the inhibition of acetylcholinesterase (AChE) activity and the copper-catalyzed click chemical reaction. In the click reaction, two hybridized DNA probes can be ligated with copper ions, inducing a fluorescence quenching during the strand displacement reaction. AChE can hydrolyze acetylthiocholine (ATCh) to form thiocholine (TCh) which contains a thiol group. TCh will react with copper ions, blocking the click reaction and a high fluorescence signal is observed. But in the presence of OPs, the activity of AChE is inhibited, releasing a high concentration of copper ions that catalyze the click chemical reaction and resulting in decreased fluorescence signals. Taking advantage of the copper-mediated signal amplification effect, the sensitivity was improved. This assay has also been applied to detect OPs in river water samples with satisfactory results, which demonstrates that the method has great potential for practical applications in environmental protection and food safety fields.


Assuntos
Inibidores da Colinesterase/análise , Compostos Organofosforados/análise , Praguicidas/análise , Espectrometria de Fluorescência/métodos , Acetilcolinesterase/química , Acetiltiocolina/química , Catálise , Quelantes/química , Inibidores da Colinesterase/química , Química Click , Cobre/química , DNA/química , Sondas de DNA/química , Fluorescência , Corantes Fluorescentes/química , Limite de Detecção , Compostos Organofosforados/química , Praguicidas/química , Rios/química , Tiocolina/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química
7.
Bioorg Med Chem Lett ; 26(9): 2268-72, 2016 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-27013393

RESUMO

With the aim of searching novel P-CABs, seven bisabolangelone oxime derivatives were designed, synthesized, characterized and evaluated the H(+),K(+)-ATPase inhibitory activities guided by computer aided drug design methods. The binding free energy calculations were in good agreement with the experiment results with the correlation coefficient R of -0.9104 between ΔGbind and pIC50 of ligands. Compound 5 exhibited the best inhibitory activity (pIC50=6.36) and most favorable binding free energy (ΔGbind=-47.67 kcal/mol) than other derivatives. The binding sites of these compounds were found to be the hydrophobic substituted groups with the Cys813 residue by the decomposed binding free energy analysis.


Assuntos
Inibidores Enzimáticos/farmacologia , ATPase Trocadora de Hidrogênio-Potássio/efeitos dos fármacos , Potássio/metabolismo , Sesquiterpenos/farmacologia , Desenho de Fármacos , Avaliação Pré-Clínica de Medicamentos , Oximas/química , Sesquiterpenos/química
8.
J Comput Aided Mol Des ; 30(1): 27-37, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26667240

RESUMO

The interaction mechanism of triazolyl substituted tetrahydrobenzofuran derivatives (compound 1 (N, N-Dipropyl-1-(2-phenyl-4,5,6,7-tetrahydrobenzofuran-4-yl)-1H-1,2,3-triazole-4-methanamine) and 2 (1-(2-Phenyl-4,5,6,7-tetrahydrobenzofuran-4-yl)-4-(morpholin-4-ylmethyl)-1H-1,2,3-triazole)) with H(+),K(+)-ATPase at different pH were studied by induced-fit docking, QM/MM optimization and MM/GBSA binding free energy calculations of two forms (neutral and protonated form) of compounds. The inhibition activity of compound 1 is measured and almost unchanged at different pH, while the activity of compound 2 increases significantly with pH value decreased. This phenomenon could be explained by their protonated form percentages and the calculated binding free energies of protonated and neutral mixture of compounds at different pH. The binding free energy of protonated form is higher than that of neutral form of compound, and the protonated form could be a powerful inhibitor of H(+),K(+)-ATPase. By the decomposed energy comparisons of residues in binding sites, Asp137 should be the key binding site to protonated form of compound because of the hydrogen bond and electrostatic interactions. These calculation results could help for further rational design of novel H(+),K(+)-ATPase inhibitors.


Assuntos
Benzofuranos/química , Benzofuranos/farmacologia , ATPase Trocadora de Hidrogênio-Potássio/metabolismo , Inibidores da Bomba de Prótons/química , Inibidores da Bomba de Prótons/farmacologia , Sequência de Aminoácidos , Animais , Sítios de Ligação , ATPase Trocadora de Hidrogênio-Potássio/química , Concentração de Íons de Hidrogênio , Simulação de Acoplamento Molecular , Dados de Sequência Molecular , Alinhamento de Sequência , Suínos , Termodinâmica
9.
Bioorg Med Chem Lett ; 25(17): 3726-9, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26141770

RESUMO

To develop more effective antitumor steroidal drugs, we synthesized a library including twenty-two novel cytotoxic 2-alkyloxyl substituted (25R)-spirostan-1,4,6-triene-3-ones and corresponding 1,2,3-triazoles through an abnormal monoepoxide ring-opening/elimination and 'click' reactions. After the cytotoxic evaluations against HepG2, Caski and HeLa cell lines, three steroidal triazoles 5b, 5f and 5m in this library were found to possess potent anti-proliferative effects against Caski cells with the half-inhibitory concentrations (IC50) of 9.4-11.8 µM. The high-efficient and straightforward process was attractive feature for facile preparation of anti-tumor steroidal triazoles.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Química Click/métodos , Espirostanos/química , Antineoplásicos/síntese química , Técnicas de Química Sintética , Cobre/química , Reação de Cicloadição , Diosgenina/química , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa/efeitos dos fármacos , Células Hep G2/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Relação Estrutura-Atividade , Triazóis/química
10.
J Struct Biol ; 185(3): 405-17, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24457027

RESUMO

Many biological complexes are naturally low in abundance and pose a significant challenge to their structural and functional studies. Here we describe a new method that utilizes strong oxidation and chemical linkage to introduce a high density of bioactive ligands onto nanometer-thick carbon films and enable selective enrichment of individual macromolecular complexes at subnanogram levels. The introduced ligands are physically separated. Ni-NTA, Protein G and DNA/RNA oligonucleotides were covalently linked to the carbon surface. They embody negligible mass and their stability makes the functionalized films able to survive long-term storage and tolerate variations in pH, temperature, salts, detergents, and solvents. We demonstrated the application of the new method to the electron microscopic imaging of the substrate-bound C3PO, an RNA-processing enzyme important for the RNA interference pathway. On the ssRNA-linked carbon surface, the formation of C3PO oligomers at subnanomolar concentrations likely mimics their assembly onto ssRNA substrates presented by their native partners. Interestingly, the 3D reconstructions by negative stain EM reveal a side port in the C3PO/ssRNA complex, and the 15Å cryoEM map showed extra density right above the side port, which probably represents the ssRNA. These results suggest a new way for ssRNAs to interact with the active sites of the complex. Together our data demonstrate that the surface-engineered carbon films are suitable for selectively enriching low-abundance biological complexes at nanomolar level and for developing novel applications on a large number of surface-presented molecules.


Assuntos
Carbono/química , Microscopia Crioeletrônica , RNA/química , DNA/química , Humanos , Nanotecnologia
11.
J Biol Chem ; 287(50): 41914-21, 2012 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-23086940

RESUMO

Carbohydrate response element-binding protein (ChREBP) is an insulin-independent, glucose-responsive transcription factor that is expressed at high levels in liver hepatocytes where it plays a critical role in converting excess carbohydrates to fat for storage. In response to fluctuating glucose levels, hepatic ChREBP activity is regulated in large part by nucleocytoplasmic shuttling of ChREBP protein via interactions with 14-3-3 proteins. The N-terminal ChREBP regulatory region is necessary and sufficient for glucose-responsive ChREBP nuclear import and export. Here, we report the crystal structure of a complex of 14-3-3ß bound to the N-terminal regulatory region of ChREBP at 2.4 Å resolution. The crystal structure revealed that the α2 helix of ChREBP (residues 117-137) adopts a well defined α-helical conformation and binds 14-3-3 in a phosphorylation-independent manner that is different from all previously characterized 14-3-3 and target protein-binding modes. ChREBP α2 interacts with 14-3-3 through both electrostatic and van der Waals interactions, and the binding is partially mediated by a free sulfate or phosphate. Structure-based mutagenesis and binding assays indicated that disrupting the observed 14-3-3 and ChREBP α2 interface resulted in a loss of complex formation, thus validating the novel protein interaction mode in the 14-3-3ß·ChREBP α2 complex.


Assuntos
Proteínas 14-3-3/química , Complexos Multiproteicos/química , Proteínas Nucleares/química , Fatores de Transcrição/química , Proteínas 14-3-3/genética , Proteínas 14-3-3/metabolismo , Animais , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos , Cristalografia por Raios X , Camundongos , Complexos Multiproteicos/genética , Complexos Multiproteicos/metabolismo , Sinais de Exportação Nuclear , Sinais de Localização Nuclear/química , Sinais de Localização Nuclear/genética , Sinais de Localização Nuclear/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Mapeamento de Peptídeos , Ligação Proteica , Estrutura Quaternária de Proteína , Estrutura Secundária de Proteína , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
12.
Bioorg Med Chem Lett ; 23(16): 4617-21, 2013 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-23830503

RESUMO

We first report the application of 3-acyl-5-hydroxybenzofurans as a scaffold to develop potential drugs for breast cancer. Seven novel derivative compounds were synthesized by using a microwave-assisted synthesis method. Those compounds exhibited different antiproliferation against human breast cancer MCF-7 cells, with the best activity of IC50=43.08µM for compound 1. A Quantum Mechanics Polarized Ligand Docking (QPLD) study was carried out to investigate the binding interactions between these compounds and estrogen receptor alpha (ERα). The simulation results showed that the trend of receptor-ligand binding interactions was same as that of their antiproliferative activities. A detailed analysis indicated that compound 1 possesses the highest Van der Waals and hydrogen bond interactions compared to the other six compounds and better inhibitors are achievable by enhancing the hydrogen bond interactions. Based on these results, we addressed that 3-acyl-5-hydroxybenzofuran is an attractive scaffold for designing drugs against breast cancer.


Assuntos
Antineoplásicos Hormonais/síntese química , Benzofuranos/síntese química , Neoplasias da Mama/tratamento farmacológico , Teoria Quântica , Antineoplásicos Hormonais/química , Antineoplásicos Hormonais/farmacologia , Benzofuranos/química , Benzofuranos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Receptor alfa de Estrogênio/metabolismo , Feminino , Humanos , Hidroxilação , Células MCF-7 , Estrutura Molecular
13.
Transl Cancer Res ; 12(10): 2673-2681, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37969401

RESUMO

Background: APOBEC3A (A3A) has been implicated to have vital prognostic value in several common cancers. This study aimed to investigate the prognostic value of A3A expression in cervical squamous cell carcinoma (CESC). Methods: This retrospective study enrolled 59 patients with CESC or cervical squamous intraepithelial neoplasia from January 2014 to January 2017 in Changhai Hospital, Naval Medical University. Then, A3A histoscores (H-scores) using immunohistochemistry (IHC) were analyzed in formalin-fixed paraffin-embedded archival tissue blocks. Moreover, overall survival was analyzed by the Kaplan-Meier method. Results: The H-score of A3A protein expression was relatively higher in CESC than in squamous intraepithelial neoplasia, and the relative expression level of normal cervical tissues was lower than that of cervical squamous intraepithelial neoplasia (P<0.001). Moreover, the H-score of poorly differentiated cases was 6, which was higher than that of moderately differentiated cases (H-score =3), while the H-score of well-differentiated cases was 2, which was lower than that of moderately differentiated cases. Moreover, patients in the A3A low expression group had higher overall survival rates by prognostic analysis (P=0.027). Conclusions: A3A protein expression was increased during CESC progression. Moreover, A3A expression was tightly related to poor prognosis in CESC. Thus, these results showed that A3A overexpression may provide a marker for poor prognosis in CESC.

14.
J Integr Med ; 21(6): 561-574, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37980180

RESUMO

OBJECTIVE: Xiaotan Sanjie recipe (XTSJ), a Chinese herbal compound medicine, exerts a significant inhibitory effect on gastric cancer (GC) metastasis. This work investigated the mechanism underlying the XTSJ-mediated inhibition of GC metastasis. METHODS: The effect of XTSJ on GC metastasis and the associated mechanism were investigated in vitro, using GC cell lines, and in vivo, using a GC mouse model, by focusing on the expression of Glc-N-Ac-transferase V (GnT-V; encoded by MGAT5). RESULTS: The migration and invasion ability of GC cells decreased significantly after XTSJ administration, which confirmed the efficacy of XTSJ in treating GC in vitro. XTSJ increased the accumulation of E-cadherin at junctions between GC cells, which was reversed by MGAT5 overexpression. XTSJ administration and MGAT5 knockdown alleviated the structural abnormality of the cell-cell junctions, while MGAT5 overexpression had the opposite effect. MGAT5 knockdown and XTSJ treatment also significantly increased the accumulation of proteins associated with the E-cadherin-mediated adherens junction complex. Furthermore, the expression of MGAT5 was significantly lower in the lungs of BGC-823-MGAT5 + XTSJ mice than in those of BGC-823-MGAT5 + solvent mice, indicating that the ability of gastric tumors to metastasize to the lung was decreased in vivo following XTSJ treatment. CONCLUSION: XTSJ prevented GC metastasis by inhibiting the GnT-V-mediated E-cadherin glycosylation and promoting the E-cadherin accumulation at cell-cell junctions. Please cite this article as: Huang N, He HW, He YY, Gu W, Xu MJ, Liu L. Xiaotan Sanjie recipe, a compound Chinese herbal medicine, inhibits gastric cancer metastasis by regulating GnT-V-mediated E-cadherin glycosylation. J Integr Med. 2023; 21(6): 561-574.


Assuntos
Medicamentos de Ervas Chinesas , Neoplasias Gástricas , Masculino , Camundongos , Animais , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Medicamentos de Ervas Chinesas/farmacologia , Glicosilação , Linhagem Celular Tumoral , Caderinas/genética , Caderinas/metabolismo
15.
J Gastrointest Oncol ; 14(4): 1659-1668, 2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37720454

RESUMO

Background: Paclitaxel (PTX) is widely used in the treatment of advanced esophageal and gastric cancer. Polymeric micelles can improve the drug-loading efficiency of PTX. However, the end groups on the amphiphilic blocks affect the drug-loading efficiency and the release kinetics of polymeric micelles. Therefore, there is an urgent need to disclose the tailoring of the core-/shell-forming terminal groups. Methods: Different from the conventional block copolymer synthesis in the reversible addition-fragmentation chain-transfer polymerization, which has a hydrophilic end group on the core-forming blocks, an alternative monomer addition method was applied to tune and obtain two block copolymers with symmetrical and similar block length PBMAn-b-PNAMm [PNAM, poly(N-acryloylmorpholine); PBMA, poly(n-butyl methacrylate)] but distinct end groups on the hydrophobic core-forming blocks, that is, HOOC-PBMA-PNAM-Phen and HOOC-PNAM-PBMA-Phen. The chemical structure of the resulting copolymers was elucidated by proton nuclear magnetic resonance spectroscopy and differential scanning calorimetry. The spherical morphology revealed by transmission electron microscopy and the uniform particle size revealed by dynamic light scattering analysis clearly confirmed the successful preparation of a PTX-polymeric micelle complex. Results: The particle sizes of HOOC-PBMA-PNAM-Phen and HOOC-PNAM-PBMA-Phen were about 40 and 235 nm respectively. The PTX loading efficiency of HOOC-PBMA-PNAM-Phen was much lower than that of HOOC-PNAM-PBMA-Phen. The PTX release from HOOC-PBMA-PNAM-Phen was much slower than that of HOOC-PNAM-PBMA-Phen. The polymers had glass transition temperature (Tg) values of 70.24 and 74.22 ℃, which was from the HOOC-PBMA-PNAM-Phen and HOOC-PNAM-PBMA-Phen micelles, respectively. The systematic study on the PTX loading and releasing profile disclosed that, compared with the HOOC-PBMA-PNAM-Phen, the micelles with Phen group on the hydrophobic block (HOOC-PNAM-PBMA-Phen) enhanced drug loading and prolonged drug release but with a larger particle size. Conclusions: The results indicated that the hydrophobic end group Phen on the core-forming blocks can promote hydrophobic drug loading and suppress burst release.

16.
Front Cardiovasc Med ; 10: 1055223, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37273879

RESUMO

Objectives: Evidence of the relationship between android fat mass and gynoid fat mass with the mortality prediction is still limited. Current study analyzed the NHANES database to investigate the relationship between android fat mass, gynoid fat mass and CVD, with all-cause mortality. Method: The study subjects were NHANES participants over 20 years old, two indicators of regional body composition, android fat and gynoid fat were measured by Dual Energy x-ray Absorptiometry (DEXA). The other various covariates data obtained from the NHANES questionnaire and laboratory measurements, including age, gender, education, race/ethnicity, uric acid, total serum cholesterol, albumin, Vitamin C, folate, alcohol drinking, smoking status, history of diabetes, and hypertension. Mortality status was ascertained from a linked mortality file prepared by the National Center for Health Statistics. The study population was divided quartiles based on the distribution of android fat mass and gynoid fat mass. The relationship between these two indicators with cardiovascular and all-cause mortality was investigated by using Cox regression. The covariates age, gender, smoking status, drinking status, history of diabetes, and history of hypertension were stratified. Results: In the fully adjusted model, Q3 had the lowest HR in android fat mass and gynoid fat mass. When examining the relationship between android fat mass and CVD mortality, current smokers and drinkers had the lowest CVD risk in Q2 [smoking: 0.21 (0.08, 0.52), drinking: 0.14 (0.04, 0.50)]. In diabetic patients, compared with Q1, other groups with increased android fat mass can significantly reduce the risk of CVD [Q4: 0.17 (0.04, 0.75), Q3: 0.18 (0.03, 1.09), Q2: 0.27 (0.09, 0.83)]. In ≥60 years old and female, the greater the gynoid fat mass, the smaller the HR of all-cause mortality [Q4 for ≥60 years old: 0.57 (0.33, 0.96), Q4 for female: 0.37 (0.23, 0.58)]. People <60 years old had a lower risk of all-cause mortality with gynoid fat mass in Q3 than those ≥60 years old [<60 years: 0.50 (0.27, 0.91), ≥60 years: 0.65 (0.45, 0.95)]. Among subjects without hypertension, the group with the largest android fat mass had the lowest risk of CVD mortality, and the group with the largest gynoid fat mass had the lowest risk of all-cause mortality [Android fat mass: 0.36 (0.16, 0.81), gynoid fat mass: 0.57 (0.39, 0.85)]. Conclusion: Moderate android fat mass and gynoid fat mass (Q3) had the most protective effect. Smokers and drinkers need to control their body fat. Being too thin is harmful to people with diabetes. Increased gynoid fat mass is a protective factor for all-cause mortality in older adults and females. Young people's gynoid fat mass is more protective in the moderate range than older people's. If no high blood pressure exists, people with more android and gynoid fat mass have a lower risk of CVD or all-cause mortality.

17.
Magn Reson Chem ; 50(4): 320-4, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22422586

RESUMO

Three new steroidal compounds with polyhydroxy groups, tupisteroide A-C (1-3), were obtained from the roots of Tupistra chinensis, together with one known compound (4) that was isolated from this plant for the first time. The structures of tupisteroide A-C were determined on the basis of one- and two-dimensional NMR spectroscopy, including (1) H-(1) H Correlation Spectroscopy, Heteronuclear Multiple Bond Correlation, and Heteronuclear Single Quantum Coherence experiments. The isolated compounds were evaluated for their cytotoxic activities against A549, HepG2, and CaSki cancer cell lines in vitro. Among them, compounds 1, 2, and 4 did not show significant inhibitory activity, but compound 3 showed cytotoxicity against A549 cancer cell lines with IC(50) values of 25.0 µM.


Assuntos
Antineoplásicos Fitogênicos/química , Medicamentos de Ervas Chinesas/química , Hidroxiesteroides/química , Liliaceae/química , Raízes de Plantas/química , Saponinas/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Hidroxiesteroides/isolamento & purificação , Hidroxiesteroides/farmacologia , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Saponinas/isolamento & purificação , Saponinas/farmacologia
18.
Zhonghua Yu Fang Yi Xue Za Zhi ; 46(4): 359-63, 2012 Apr.
Artigo em Zh | MEDLINE | ID: mdl-22800638

RESUMO

OBJECTIVE: To evaluate the relationship between peroxisome proliferator-activated receptor-γ2 (PPARγ2) Pro12Ala polymorphism and type 2 diabetes mellitus (T2DM) in Chinese Han population. METHODS: PubMed, Chinese Biomedicine Database (CBM), China National Knowledge Infrastructure (CNKI) and Wanfang database were searched for all relevant articles investigating the association between PPARγ2 Pro12Ala polymorphism and T2DM that were available from January, 1990 to June, 2011. A total of 29 relevant articles were selected. A Meta-analysis was performed to estimate heterogeneity and the pooled odds ratio (OR) to evaluate the relationship between PPARγ2 Pro12Ala polymorphism and T2DM. The sensitivity analysis was also assessed. RESULTS: A total of 21 qualified articles including 3870 patients with T2DM and 3333 healthy controls were analyzed in the study. The frequencies of the allele Ala12 in T2DM and control groups were 4.13% (320/7740) and 4.56% (304/6666), respectively. There were not heterogeneity (χ(2) = 25.96, P = 0.17) among the 21 qualified articles. The pooled OR (95%CI) value of the frequencies of the PPARγ2 genotype (PA + AA)/PP calculated by fixed effects model was 0.96 (0.81 - 1.14) (P = 0.64). There was not heterogeneity among the remaining articles after excluding the article with the largest weight and the article with larger frequencies of the allele Ala12 respectively (χ(2) values were 24.23, 16.87 respectively, both P values > 0.05). The pooled OR (95%CI) value of the frequencies of the PPARγ2 genotype (PA + AA)/PP of the remaining articles were 1.01 (0.84 - 1.21) and 1.07 (0.89 - 1.28) after excluding the article with the largest weight and the article with larger frequencies of the allele Ala12 (both P values > 0.05). CONCLUSION: PPARγ2 Pro12Ala polymorphism was not associated with type 2 diabetes mellitus in Chinese Han population.


Assuntos
Diabetes Mellitus Tipo 2/genética , PPAR gama/genética , Polimorfismo de Nucleotídeo Único , Alelos , Povo Asiático/genética , China , Frequência do Gene , Genótipo , Humanos
19.
Thorac Cancer ; 13(13): 1974-1985, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35599447

RESUMO

BACKGROUND: This study intended to investigate the potential mechanism of microRNA-200c-3p (miR-200c-3p) and miR-485-5p in mediating the cisplatin (DDP) resistance in non-small cell lung cancer (NSCLC). METHODS: Quantitative real-time polymerase chain reaction (qRT-PCR) was applied to measure the expression of miR-200c-3p, miR-485-5p, and ribonucleotide reductase regulatory subunit M2 (RRM2) messenger RNA (mRNA). 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to analyze the DDP resistance and the proliferation of NSCLC cells. Colony formation assay was used to assess cell proliferation. Transwell assays were used to evaluate cell migration and invasion. The target relationship between RRM2 and miR-200c-3p or miR-485-5p was verified using dual-luciferase reporter assay. The protein level of RRM2 was measured using Western blot assay. Animal experiments were conducted to analyze the roles of miR-200c-3p and miR-485-5p in the DDP resistance of xenograft tumors in vivo. RESULTS: MiR-200c-3p and miR-485-5p were both downregulated in DDP-resistant NSCLC tissues and cell lines. Overexpressing miR-200c-3p or miR-485-5p suppressed the DDP resistance and malignant behaviors of NSCLC cells. MiR-200c-3p played a synergistic role with miR-485-5p in regulating the chemo-resistance and biological behaviors NSCLC cells. RRM2 was confirmed as a target of miR-200c-3p and miR-485-5p. RRM2 silencing restrained the DDP resistance and progression of NSCLC. RRM2 overexpression partly reversed miR-200c-3p or miR-485-5p-induced influences in NSCLC cells. The overexpression of miR-200c-3p or miR-485-5p aggravated DDP-mediated suppressive effect on tumor growth in vivo. CONCLUSION: MiR-200c-3p or miR-485-5p enhanced the DDP sensitivity and suppressed the malignant behaviors of NSCLC cells partly through targeting RRM2.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , MicroRNAs , Animais , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Proliferação de Células , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Oxirredutases/genética , Oxirredutases/metabolismo , Fenótipo
20.
J Integr Med ; 20(2): 145-152, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34969649

RESUMO

BACKGROUND: Core muscle functional strength training (CMFST) has been reported to reduce injuries to the lower extremity. However, no study has confirmed whether CMFST can reduce the risk of low back pain (LBP). OBJECTIVE: This study identified the effects of CMFST on the incidence of LBP in military recruits. DESIGN, SETTING, PARTICIPANTS AND INTERVENTION: We performed a prospective, open-label, randomized, controlled study in a population of young healthy male naval recruits from a Chinese basic combat training program. Participants were randomly assigned to either the core group or the control group. In additional to normal basic combat training, recruits in the core group underwent a CMFST program for 12 weeks, while recruits in the control group received no extra training. MAIN OUTCOME MEASURES: At the beginning of the study and at the 12th week, the number of participants with LBP was counted, and lumbar muscle endurance was measured. In addition, when participants complained of LBP, they were assessed using the visual analog scale (VAS) and Roland Morris Disability Questionnaire (RMDQ). RESULTS: A total of 588 participants were included in the final analysis (295 in the core group and 293 in the control group). The incidence of LBP in the control group was about twice that of the core group over the 12-week study (20.8% vs 10.8%, odds ratio: 2.161-2.159, P < 0.001). The core group had better lumbar muscle endurance at 12 weeks than the control group ([200.80 ± 92.98] s vs [147.00 ± 84.51] s, P < 0.01). There was no significant difference in VAS score between groups, but the core group had a significantly lower RMDQ score at week 12 than the control group (3.33 ± 0.58 vs 5.47 ± 4.41, P < 0.05). CONCLUSION: This study demonstrated that the CMFST effectively reduced the incidence of LBP, improved lumbar muscle endurance, and relieved the dysfunction of LBP during basic military training.


Assuntos
Dor Lombar , Militares , Treinamento Resistido , Humanos , Dor Lombar/prevenção & controle , Masculino , Músculos , Estudos Prospectivos , Resultado do Tratamento
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