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1.
Fitoterapia ; 177: 106084, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38897251

RESUMO

Three new ergosterols featuring with a highly conjugated ring system, psathrosterols C-E (1-3), have been isolated from the fungus Psathyrella rogueiana. The structures with the absolute configurations were elucidated by means of spectroscopic methods and single crystal X-ray diffraction. Compounds 1-3 exhibit inhibitory activity against NO production with IC50 values ranging from 8.4 to 21.8 µM. Compound 1 inhibits the LPS-induced proliferation of B lymphocyte cells with an IC50 value of 12.3 µM.

2.
Small ; : e2401308, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773889

RESUMO

Incorporating ultralow loading of nanoparticles into polymers has realized increases in dielectric constant and breakdown strength for excellent energy storage. However, there are still a series of tough issues to be dealt with, such as organic solvent uses, which face enormous challenges in scalable preparation. Here, a new strategy of dual in situ synthesis is proposed, namely polymerization of polyethylene terephthalate (PET) synchronizes with growth of calcium borate nanoparticles, making polyester nanocomposites from monomers directly. Importantly, this route is free of organic solvents and surface modification of nanoparticles, which is readily accessible to scalable synthesis of polyester nanocomposites. Meanwhile, uniform dispersion of as ultralow as 0.1 wt% nanoparticles and intense bonding at interfaces have been observed. Furthermore, the PET-based nanocomposite displays obvious increases in both dielectric constant and breakdown strength as compared to the neat PET. Its maximum discharged energy density reaches 15 J cm-3 at 690 MV m-1 and power density attains 218 MW cm-3 under 150 Ω resistance at 300 MV m-1, which is far superior to the current dielectric polymers that can be produced at large scales. This work presents a scalable, safe, low-cost, and environment-friendly route toward polymer nanocomposites with superior capacitive performance.

3.
Phys Chem Chem Phys ; 25(27): 18030-18037, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37378512

RESUMO

Improved dielectric constant and breakdown strength facilitates excellent energy storage density of polymer dielectrics, which is positive to miniaturize dielectric capacitors in electronic and electrical systems. Although coating polar substances on nanoparticles enhances the dielectric constants of polymer nanocomposites, it usually causes local electric field concentration, leading to poor breakdown strength. Here, fluoropolymers with tailorable fluorine content (PF0, PF30 and PF60) are coated on BaTiO3 (BT) nanoparticles to construct typical core-shell structures that are further blended with poly(vinylidenefluoride-co-hexafluoropropylene) (P(VDF-HFP)) to obtain BT@PF/P(VDF-HFP) nanocomposites. Uniform dispersion of nanoparticles and excellent compatibility of interfaces are observed for the samples. In addition, the dielectric constant gradually increases from 8.03 to 8.26 to 9.12 for the nanocomposites filled with 3 wt% BT@PF0, BT@PF30 and BT@PF60, respectively. However, 3 wt% BT@PF30/P(VDF-HFP) has the highest breakdown strength (455 kV mm-1) among the nanocomposites, which is as good as neat P(VDF-HFP). More importantly, BT@PF30 rather than BT@PF60 possesses the maximum discharged energy density (11.56 J cm-3 at 485 kV mm-1), which is about 1.65 times that of neat P(VDF-HFP). This work proposes a facile experimental route to optimize the dielectric constants of the shell layer to couple the dielectric constants between the nanoparticles, shell layer and polymer matrix, which contributes to alleviating the local electric field concentration for excellent breakdown strength and electrical energy storage of polymer nanocomposites.

4.
Adv Ther ; 40(3): 844-852, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36370289

RESUMO

INTRODUCTION: Fixation of femoral neck fractures with cannulated screws is an accepted method. This study aimed to compare a novel guide device and conventional technique with regard to the accuracy, operation time, fluoroscopy numbers, and drilling attempts during the insertion of cannulated screws to internal fixation of femoral neck fractures. METHODS: This retrospective study included 60 patients with intracapsular femoral neck fractures who were treated with cannulated screws from January 2020 to June 2021. Three screws were inserted into the femoral neck by conventional technique or using the novel guide device. The operative time, total drilling attempts, and fluoroscopy numbers were evaluated. The precision of implant placement was evaluated by screw parallelism and spread. The patients were followed for 12-24 months. RESULTS: The fluoroscopy numbers and operation time of the guide-device-assisted group were shorter than for the conventional group (p < 0.05). The total drilling attempts were significantly lower with the guide device than in the conventional group (p < 0.05). The guide-device-assisted group had better screw parallelism and greater spread than the conventional group (p < 0.05). CONCLUSIONS: The novel guide device may be an effective assistant instrument for internal fixation of femoral neck fracture with cannulated screws.


Assuntos
Fraturas do Colo Femoral , Humanos , Estudos Retrospectivos , Fraturas do Colo Femoral/diagnóstico por imagem , Fraturas do Colo Femoral/cirurgia , Fluoroscopia , Fixação Interna de Fraturas/métodos , Parafusos Ósseos
5.
Materials (Basel) ; 14(23)2021 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-34885625

RESUMO

Gd and Yb elements have high chemical stability, which can stabilize the solid solution in ZrO2. Gd2O3 and Yb2O3 have high melting points, and good oxidation resistance in extreme environments, stable chemical properties. Therefore, Gd2O3 and Yb2O3 were added to ZrO2 to stabilize oxides, improve the high temperature stability, and effectively decrease the thermal conductivity at high temperature. In this work, 5 wt% Yb2O3 and 5 wt%, 10 wt%, 15 wt% Gd2O3 were doped into 8 wt% Y2O3 stabilized ZrO2 (8YSZ) powders as thermal barrier coating materials, and sintered at 1650 °C for 6 h, 12 h, 24 h. The effects of Gd2O3 addition on the microstructure, density, thermal conductivity, hardness, and fracture toughness of Gd2O3-Yb2O3-Y2O3-ZrO2 (GYYZO) bulk composite ceramics were investigated. It was found that the densification of the 8YSZ bulk and GYYZO bulk with 15 wt% Gd2O3 reached 96.89% and 96.22% sintered at 1650 °C for 24 h. With the increase of Gd2O3 addition, the hardness, elastic modulus and fracture toughness of the GYYZO bulk increased and the thermal conductivity and thermal expansion coefficient of the GYYZO bulk decreased. GYYZO bulk with 15 wt% Gd2O3 sintered at 1650 °C for 24h had the highest hardness, elastic modulus and fracture toughness of 15.61 GPa, 306.88 GPa, 7.822 MPa·m0.5, and the lowest thermal conductivity and thermal expansion coefficient of 1.04 W/(m·k) and 7.89 × 10-6/°C at 1100 °C, respectively. The addition of Gd2O3 into YSZ could not only effectively reduce the thermal conductivity but also improve the mechanical properties, which would improve the thermal barrier coatings' performances further.

6.
Phys Chem Chem Phys ; 23(46): 26219-26226, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34787124

RESUMO

Integrating high-loading dielectric nanoparticles into polar polymer matrices potentially can profit the intrinsic polarization of each phase and allow for greatly enhanced dielectric properties in polymer nanocomposites. It is however challenging to achieve desirable highly filled polar polymer composites because of the lack of efficient approaches to disperse nanoparticles and maintain interfacial compatibility. Here, we report a versatile route to fabricate highly filled barium titanate/fluorinated silicone rubber (BT/FSR) nanocomposites by "thiol-ene click" and isostatic pressing techniques. The loaded BT nanoparticles (from 82 wt% to 90 wt%) are chemically bonded with FSR in the nanocomposites. The existence of the polar group (-CH2CF3) of the polymer matrix does not affect the uniform dispersion of the nanoparticles or the good interfacial compatibility. The 90 wt% BT/FSR nanocomposite shows the highest dielectric constant of 57.8 at 103 Hz, while the loss tangent can be kept below 0.03. Besides, BT/FSR nanocomposites display higher breakdown strength than BT/SR nanocomposites. This work offers a facile strategy towards superior dielectric properties of polymer nanocomposites.

7.
Curr Top Med Chem ; 20(16): 1481-1492, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32156236

RESUMO

1,3,5-Triazine and azole can interact with various therapeutic targets, and their derivatives possess promising in vitro and in vivo anticancer activity. Hybrid molecules have the potential to enhance efficiency, overcome drug resistance and reduce side effects, and many hybrid molecules are under different phases of clinical trials, so hybridization of 1,3,5-triazine with azole may provide valuable therapeutic intervention for the treatment of cancer. Substantial efforts have been made to develop azole-containing 1,3,5-triazine hybrids as novel anticancer agents, and some of them exhibited excellent activity. This review emphasizes azole-containing 1,3,5-triazine hybrids with potential anticancer activity, and the structure-activity relationships as well as the mechanisms of action are also discussed to provide comprehensive and target-oriented information for the development of this kind of anticancer drugs.


Assuntos
Antineoplásicos/farmacologia , Azóis/farmacologia , Triazinas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Azóis/síntese química , Azóis/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Relação Estrutura-Atividade , Triazinas/síntese química , Triazinas/química
8.
Curr Top Med Chem ; 20(16): 1499-1503, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32156238

RESUMO

AIM: To develop novel anti-breast cancer agents and discuss the structure-activity relationship of bis-isatin scaffolds. BACKGROUND: Breast cancer is the most common invasive cancer and the second leading cause of cancer death in women after lung cancer. Bis-isatin scaffolds possess potential anti-breast cancer activity, and some of them such as Indirubin could induce cancer cells apoptosis via multiply mechanisms. OBJECTIVE: The primary objective of this study was to evaluate the potential of bis-isatin scaffolds with alkyl/ether linkers between the two isatin moieties against different human breast cancer cell lines including MCF-7, AU565, MDA-MB-231, MDA-MB-435 and MDA-MB-468 cells. METHODS: The synthesized bis-isatin scaffolds with alkyl/ether linker between the two isatin moieties were evaluated for their in vitro activity against MCF-7, AU565, MDA-MB-231, MDA-MB-435, and MDA-MB-468 human breast cancer cell lines by MTT assay. RESULTS: All the synthesized compounds (IC50: 38.3-197.6 µM) possess considerable activity against MCF-7, AU565, MDA-MB-231, MDA-MB-435, and MDA-MB-468 human breast cancer cell lines, and the most potent compound 4e (IC50: 38.3-63.5 µM) was no inferior to Cisplatin (IC50: 20.1-38.6 µM) against the five tested human breast cancer cell lines. CONCLUSION: All the synthesized bis-isatin scaffolds were active against a panel of breast cancer cell lines, highlighting the significance of exploring the bis-isatin scaffolds to fight against breast cancers. The enriched structure-activity relationship may set up the direction for the rational design and development of novel bis-isatin scaffolds with higher efficiency.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Isatina/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Isatina/síntese química , Isatina/química , Estrutura Molecular , Relação Estrutura-Atividade
9.
J Asian Nat Prod Res ; 21(2): 123-128, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29069939

RESUMO

Two new illudane sesquiterpenoids, craterellins D and E (1 and 2), and one new menthane monoterpene, 4-hydroxy-4-isopropenyl-cyclohexanemethanol acetate (3), were isolated from cultures of Craterellus cornucopioides. Structures of 1-3 were elucidated on the basis of extensive spectroscopic analysis. Their cytotoxic activities on five tumor cell lines were evaluated.


Assuntos
Basidiomycota/química , Monoterpenos/química , Sesquiterpenos/química , Agaricales/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular , Humanos , Estrutura Molecular , Sesquiterpenos Policíclicos
10.
Mol Med Rep ; 17(6): 8228-8236, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29693161

RESUMO

The aim of the present study was to investigate the correlation between the multi­drug resistance of Shigella flexneri and the drug­resistant gene cassette carried by integrons; in the meanwhile, to detect the associations between drug­resistance and gene mutations of the active efflux pump acrAB­tolC gene and its regulatory genes, including marOR, acrR and soxS. A total of 158 isolates were isolated from the stool samples of 1,026 children with diarrhoea aged 14 years old between May 2012 and October 2015 in Henan. The K­B method was applied for the determination of drug resistance of Shigella flexneri, and polymerase chain reaction amplification was used for class 1, 2 and 3 integrase genes. Enzyme digestion and sequence analysis were performed for the variable regions of positive strains. Based on the drug sensitivity assessment, multi­drug resistant strains that were resistant to five or more antibiotics, and sensitive strains were selected for amplification. Their active efflux pump genes, acrA and acrB, and regulatory genes, marOR, acrR and soxS, were selected for sequencing. The results revealed that 91.1% of the 158 strains were multi­resistant to ampicillin, chloramphenicol, tetracycline and streptomycin, and 69.6% of the strains were multi­resistant to sulfamethoxazole/trimethoprim. The resistance to ceftazidime, ciprofloxacin and levofloxacin was <32.9%. All strains (100%) were sensitive to cefoxitin, cefoperazone/sulbactam and imipenem. The rate of the class 1 integron positivity was 91.9% (144/158). Among these class 1 integron­positive strains, 18 strains exhibited the resistance gene cassette dfrV in the variable region of the strain, four strains exhibited dfrA17­aadA5 in the variable region and 140 strains exhibited blaOXA­30­aadA1 in the variable region. Four strains showed no resistance gene in the variable regions. The rate of class 2 integron positivity was 86.1% (136/158), and all positive strains harboured the dfrA1­sat1­aadA resistance gene cassette in the variable region. The class 3 integrase gene was not detected in these strains. The gene sequencing showed the deletion of base CATT in the 36, 37, 38, 39 site in the marOR gene, which is a regulatory gene of the active efflux pump, AcrAB­TolC. Taken together, the multi­drug resistance of Shigella flexneri was closely associated with gene mutations of class 1 and 2 integrons and the marOR gene.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Regulação Bacteriana da Expressão Gênica , Genes Bacterianos , Mutação , Shigella flexneri/efeitos dos fármacos , Shigella flexneri/genética , Adolescente , Criança , Pré-Escolar , Disenteria Bacilar/tratamento farmacológico , Disenteria Bacilar/microbiologia , Feminino , Humanos , Lactente , Masculino , Testes de Sensibilidade Microbiana , Fenótipo
11.
Cardiovasc Intervent Radiol ; 39(1): 81-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26044668

RESUMO

PURPOSE: To compare the efficacy of percutaneous cementoplasty (PCP) with and without interventional internal fixation (IIF) on malignant impending pathological fracture of proximal femur. METHODS: A total of 40 patients with malignant impending pathological fracture of proximal femur were selected for PCP and IIF (n = 19, group A) or PCP alone (n = 21, group B) in this non-randomized prospective study. Bone puncture needles were inserted into the proximal femur, followed by sequential installation of the modified trocar inner needles through the puncture needle sheath. Then, 15-45 ml cement was injected into the femur lesion. RESULTS: The overall excellent and good pain relief rate during follow-ups were significantly higher in group A than that in group B (89 vs. 57 %, P = 0.034). The average change of VAS, ODI, KPS, and EFES in group A were significantly higher than those in group B at 1-, 3-, 6-month, 1-year (P < 0.05). Meanwhile, The stability of the treated femur was significantly higher in group A than that in group B (P < 0.05). CONCLUSION: PCP and IIF were not only a safe and effective procedure, but resulted in greater pain relief, bone consolidation, and also reduced the risk of fracture than the currently recommended approach of PCP done on malignant proximal femoral tumor.


Assuntos
Cementoplastia/métodos , Fraturas do Fêmur/prevenção & controle , Neoplasias Femorais/complicações , Fixação Interna de Fraturas/métodos , Fraturas Espontâneas/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
12.
Ying Yong Sheng Tai Xue Bao ; 27(12): 3838-3844, 2016 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-29704341

RESUMO

Taking the Quercus liaotungensis middle-aged forests in Huanglong and Qiaoshan Mountains as study objects, the average size of individual trees of Q. liaotungensis, yield and rate of its reproductive modules, as well as their spatial distribution characteristics were investigated in five years after thinning at different intensities (CK, 10%, 20% and 30%), in order to demonstrate the impact of thinning intensity on reproductive modules of Q. liaotungensis. Thinning intensity had no significant effect on average height and average DBH, while it had significant positive correlation with crown area and crown volume. The yield of generative shoots, young fruits and mature fruits increased with thinning intensity, but vegetative shoots, staminate inflorescence, staminate flowers and pistillate flowers of Q. liaotungensis had little change. The yield of generative shoots, young fruits and mature fruits had raised significantly under 20% thinning, and reached the maximum under 30% thinning intensity. The rate of generative shoots and fruit setting rate increased with thinning intensity, and reached significant level under 20% or 30% thinning compared with the control. About three-quarters of the generative shoots, female and male flowers centered in the upper canopy, and the rest were in the lower part. Numbers of reproductive modules at sunny side accounted for about 65% of the total. The lower crown, shaded generative shoots, pistillate flowers and staminate inflorescence increased with the increasing thinning intensity, and the upper crown, sunny generative shoots, pistillate flowers and staminate inflorescence showed a decreasing trend with the increasing thinning intensity. Thinning at the intensity of 30% (canopy density 0.6) was the best, which could greatly improve the fruit set percentage of Q. liaotungensis and its mature rate, so as to improve the seed yield and quality, providing the guarantee for the seed collection and natural regeneration of Q. liaotungensis forests.


Assuntos
Florestas , Quercus/fisiologia , China , Flores , Agricultura Florestal , Frutas , Reprodução , Sementes , Árvores/fisiologia
13.
Korean J Radiol ; 15(6): 797-801, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25469092

RESUMO

Glucocorticosteroid-induced osteoporosis is the most frequent of all secondary types of osteoporosis, and can increase the risk of vertebral compression fractures (VCFs). There are promising additions to current medical treatment for appropriately selected osteoporotic patients. Few studies have reported on the efficiency of percutaneous vertebroplasty (PVP) or kyphoplasty for whole thoracic and lumbar glucocorticosteroid-induced osteoporotic vertebral compression fractures. We report a case of a 67-year-old man with intractable pain caused by successional VCFs treated by PVP.


Assuntos
Fraturas por Compressão/diagnóstico por imagem , Glucocorticoides/efeitos adversos , Osteoporose/induzido quimicamente , Idoso , Artrite Reumatoide/tratamento farmacológico , Glucocorticoides/uso terapêutico , Humanos , Cifoplastia , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Masculino , Osteoporose/diagnóstico por imagem , Osteoporose/cirurgia , Fibrose Pulmonar/tratamento farmacológico , Radiografia , Vértebras Torácicas/diagnóstico por imagem , Vértebras Torácicas/cirurgia , Vertebroplastia
14.
Anticancer Res ; 34(6): 2883-97, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24922651

RESUMO

AIM: Endometrial stromal sarcoma (ESS) is a rare gynecological mesenchymal malignancy with only few therapeutic options. This study aimed to investigate the efficacy of the histone deacetylase (HDAC) inhibitor suberanilohydroxamic acid (SAHA) combined with inhibitors of the phosphoinositid-3-Kinase (PI3K) pathway in ESS therapy. MATERIALS AND METHODS: The effects of SAHA combined with inhibitor of PI3K (LY294002, LY), mammalian target of rapamycin mTOR (rapamycin), and their combination on cell growth and the PI3K pathway in two ESS cell lines (ESS-1 and MES-SA) and one non-neoplastic cell line HESC, were investigated. RESULTS: SAHA reduced growth of the three cell lines by inhibiting protein kinase B AKT and mTOR/p70S6K cascade activation. SAHA combined with LY or rapamycin, or both, synergistically reduced p-p70S6K and p-4E-BP1 levels. SAHA combined with LY and rapamycin led to the strongest growth inhibition and slowest growth recovery among the combination treatments. CONCLUSION: SAHA combined with inhibition of PI3K and mTOR could represent an efficient therapy option for patients with ESS.


Assuntos
Neoplasias do Endométrio/metabolismo , Histona Desacetilases/química , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Sarcoma do Estroma Endometrial/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/antagonistas & inibidores , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Apoptose/efeitos dos fármacos , Western Blotting , Proteínas de Ciclo Celular , Proliferação de Células/efeitos dos fármacos , Neoplasias do Endométrio/tratamento farmacológico , Neoplasias do Endométrio/patologia , Inibidores Enzimáticos/farmacologia , Feminino , Imunofluorescência , Histona Desacetilases/metabolismo , Humanos , Fosfatidilinositol 3-Quinases/metabolismo , Fosfoproteínas/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Sarcoma do Estroma Endometrial/tratamento farmacológico , Sarcoma do Estroma Endometrial/patologia , Serina-Treonina Quinases TOR/metabolismo , Células Tumorais Cultivadas
15.
J Cell Mol Med ; 16(9): 2127-39, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22225925

RESUMO

Endometriosis is a disease characterized by the localization of endometrial tissue outside the uterine cavity. The differences observed in migration of human endometrial stromal cells (hESC) obtained from patients with endometriosis versus healthy controls were proposed to correlate with the abnormal activation of Raf-1/ROCKII signalling pathway. To evaluate the mechanism by which Raf-1 regulates cytoskeleton reorganization and motility, we used primary eutopic (Eu-, n = 16) and ectopic (Ec-, n = 8; isolated from ovarian cysts) hESC of patients with endometriosis and endometriosis-free controls (Co-hESC, n = 14). Raf-1 siRNA knockdown in Co- and Eu-hESC resulted in contraction and decreased migration versus siRNA controls. This phenotype was reversed following the re-expression of Raf-1 in these cells. Lowest Raf-1 levels in Ec-hESC were associated with hyperactivated ROCKII and ezrin/radixin/moesin (E/R/M), impaired migration and a contracted phenotype similar to Raf-1 knockdown in Co- and Eu-hESC. We further show that the mechanism by which Raf-1 mediates migration in hESC includes direct myosin light chain phosphatase (MYPT1) phosphorylation and regulation of the levels of E/R/M, paxillin, MYPT1 and myosin light chain (MLC) phosphorylation indirectly via the hyperactivation of ROCKII kinase. Furthermore, we suggest that in contrast to Co-and Eu-hESC, where the cellular Raf-1 levels regulate the rate of migration, the low cellular Raf-1 content in Ec-hESC, might ensure their restricted migration by preserving the contracted cellular phenotype. In conclusion, our findings suggest that cellular levels of Raf-1 adjust the threshold of hESC migration in endometriosis.


Assuntos
Endometriose/fisiopatologia , Células Epiteliais/citologia , Proteínas Proto-Oncogênicas c-raf/metabolismo , Adolescente , Adulto , Movimento Celular , Células Cultivadas , Proteínas do Citoesqueleto/metabolismo , Endometriose/genética , Endométrio/metabolismo , Células Epiteliais/metabolismo , Feminino , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Proteínas de Membrana/metabolismo , Proteínas dos Microfilamentos/metabolismo , Fosfatase de Miosina-de-Cadeia-Leve/genética , Fosfatase de Miosina-de-Cadeia-Leve/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-raf/genética , Transdução de Sinais , Células Estromais , Adulto Jovem , Quinases Associadas a rho/genética , Quinases Associadas a rho/metabolismo
16.
Lab Invest ; 91(7): 1079-91, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21519332

RESUMO

Tissue-type plasminogen activator (tPA) is a major protease of the central nervous system. Most studies to date have used in situ- or gel-based zymographic assays to monitor in vivo changes in neural tPA activity. In this study, we demonstrate that the amidolytic assay can be adapted to accurately detect changes in net tPA activity in mouse brain tissues. Using the amidolytic assay, we examined differences in net tPA activity in the cerebral cortex, sub-cortical structures and cerebellum in wildtype (WT) and tPA(-/-) mice, and in transgenic mice selectively overexpressing tPA in neurons. In addition, we assessed changes in endogenous net tPA activity in WT mice following morphine administration, epileptic seizures, traumatic brain injury and ischaemic stroke-neurological settings in which tPA has a known functional role. Under these conditions, acute and compartment-specific regulation of tPA activity was observed. tPA also participates in various forms of chronic neurodegeneration. Accordingly, we assessed tPA activity levels in mouse models of Alzheimer's disease (AD) and spinocerebellar ataxia type-1 (SCA1). Decreased tPA activity was detected in the cortex and subcortex of AD mice, whereas increased tPA activity was found in the cerebellum of SCA1 mice. These findings extend the existing hypotheses that low tPA activity promotes AD, whereas increased tPA activity contributes to cerebellar degeneration. Collectively, our results exemplify the utility of the amidolytic assay and emphasise tPA as a complex mediator of brain function and dysfunction. On the basis of this evidence, we propose that alterations in tPA activity levels could be used as a biomarker for perturbations in brain homeostasis.


Assuntos
Lesões Encefálicas/metabolismo , Isquemia Encefálica/metabolismo , Compartimento Celular , Morfina/administração & dosagem , Ativador de Plasminogênio Tecidual/metabolismo , Animais , Sequência de Bases , Primers do DNA , Camundongos , Camundongos Transgênicos , Reação em Cadeia da Polimerase
17.
Exp Aging Res ; 36(3): 359-70, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20544453

RESUMO

Several studies have shown that aging is associated with quantitative and qualitative alterations of the stem and progenitor cell compartment. The current results indicate that there is a significant age-associated decline in the proliferative capacity of rat myeloid progenitor cells. In contrast, no difference was found in the frequency of myeloid progenitor cells in the bone marrow of young versus old rats. Furthermore, a significant shift towards higher proliferative capacity of myeloid progenitors was observed after lifelong voluntary exercise. These data emphasize that aging is accompanied by a loss of proliferative capacity and that voluntary exercise could retard this process.


Assuntos
Envelhecimento/fisiologia , Células da Medula Óssea/fisiologia , Células-Tronco Hematopoéticas/fisiologia , Animais , Contagem de Células , Proliferação de Células , Separação Celular , Fator Estimulador de Colônias de Granulócitos e Macrófagos/fisiologia , Masculino , Atividade Motora/fisiologia , Células Progenitoras Mieloides/fisiologia , Condicionamento Físico Animal/fisiologia , Ratos , Ratos Sprague-Dawley
18.
Chem Commun (Camb) ; (40): 6089-91, 2009 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-19809653

RESUMO

PPh3-catalyzed alpha-addition reactions of 1-(o-hydroxyaryl)-1,3-diketones to terminal alkynoates involving carbon-carbon bond cleavage to give multifunctional vinylesters are described.

19.
J Spinal Cord Med ; 31(3): 279-84, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18795477

RESUMO

OBJECTIVE: To determine the association between levels of basic metabolic elements and degeneration and ossification of the ligamentum flavum (LF). SUBJECTS: Fourteen consecutive patients with degenerative lumbar stenosis, 11 with ossification of the thoracic ligamenta flava, and 11 control subjects. METHODS: The basic elements of calcium (Ca), phosphorus (P), magnesium (Mg), zinc (Zn), copper (Cu), manganese (Mn), molybdenum (Mo), and fluoride (F) in the specimens were measured using atomic absorption spectrometry, the phosphomolybdic blue method, and a fluoride-selected electrode. RESULTS: Ca content and the ratio of Ca/Mg in the LF specimens increased significantly in the sequence of control, degeneration, and ossification groups. Compared with values for the control group, the Zn, Mn, and Mo contents in the ossification and degeneration groups were significantly lower (P < 0.01); in contrast, Cu content was significantly higher (P < 0.01). As to F, its content in the specimens of the ossification group was much higher than those in the degeneration and control groups (P < 0.01); the F content in the ligamenta flava and sera from patients with fluorosis was also significantly higher than in those from patients without fluorosis (P < 0.01). Compared with the control group, there were no differences in the F content in serum from patients without fluorosis; however, the F content in ligamenta flava specimens from patients without fluorosis was significantly higher (P < 0.01). CONCLUSIONS: There are trends in the contents of basic metabolic elements in the degeneration and ossification of ligamenta flava. These basic metabolic elements may play an important role in this process.


Assuntos
Elementos Químicos , Ligamento Amarelo/metabolismo , Ossificação Heterotópica/metabolismo , Ossificação Heterotópica/patologia , Osteonecrose/metabolismo , Adulto , Estudos de Casos e Controles , Feminino , Fluoretos/metabolismo , Humanos , Masculino , Manganês/metabolismo , Pessoa de Meia-Idade , Fósforo/metabolismo , Estudos Retrospectivos , Espectrofotometria Atômica/métodos , Zinco/metabolismo
20.
Exp Gerontol ; 42(11): 1072-8, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17851010

RESUMO

Reactive oxygen species (ROS) play important roles in cellular senescence and organismic aging. Furthermore, they have been implicated in some of the adverse effects of chronic stress due to elevated peripheral levels of catecholamines. Here, we applied three different techniques to individually compare the systemic and intracellular oxidative stress in aged (23 months) and young (5 months) Sprague-Dawley rats, and in young rats treated for 12 or 24 h with norepinephrine (NE). Thiol groups of blood serum proteins (RSH) were determined by means of Ellman's reaction. Intracellular ROS were assessed in spleen cells and peripheral blood lymphocytes (PBL) by carbonylation of cellular (spleen) proteins as determined by immunoblotting (Oxyblot) and/or by means of 2',7'-dichlorofluorescein (DCF) fluorescence. As compared to the young, untreated controls, both old rats and NE treated young rats showed similarly lowered RSH values paralleled by elevated intracellular ROS levels or enhanced Oxyblot signals. Individual RSH values were highly significantly, negatively correlated with respective Oxyblot data as well as with DCF fluorescence. The results confirm the roles of ROS in aging and adrenergic stress in the rat model, and suggest that the decrease in RSH of blood serum may be taken as a valid indicator for the enhanced oxidative stress in lymphocytes.


Assuntos
Envelhecimento/fisiologia , Norepinefrina/farmacologia , Espécies Reativas de Oxigênio/análise , Compostos de Sulfidrila/análise , Animais , Senescência Celular , Immunoblotting , Peroxidação de Lipídeos , Linfócitos/metabolismo , Masculino , Estresse Oxidativo , Ratos , Ratos Sprague-Dawley , Baço/citologia , Baço/metabolismo
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