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1.
ACS Omega ; 8(48): 45801-45816, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38075842

RESUMO

Hydrogen has been regarded as an important type of renewable energy; however, the usage of pure hydrogen remains a challenge due to the difficulty of transportation and storage. To facilitate the hydrogen usage, it has been proposed to add hydrogen into the existing natural gas pipeline and storage systems, and therefore, the blended hydrogen is injected into the underground gas reservoirs, which is often used for the seasonal storage of natural gas. However, the mechanism of the H2/CH4 mixture storage in the porous formations of underground reservoirs still remains unclear. In this work, we have used molecular simulations to study the storage of the H2/CH4 mixture in dry and wet kaolinite pores of gibbsite and siloxane structures aiming at the clays in the underground porous reservoirs. The results showed that the hydrogen storage density increases as the injected H2 fraction increases in the dry pores but is nearly not affected by the pore size in the range of 5-200 nm. For the H2 fraction below 20%, the percentage of the H2 stored in the pores from the injected gas mixture is higher than that of CH4, and the larger pores are more preferential for H2 storage, but the H2 molecule distribution is more diffused than that of CH4 across the pore. The CH4 molecules adopt the tripod and inclined configurations with an angle of 110° or 70° toward the surface, while the H2 molecules are perpendicular to the surface. But both the molecular structures of H2 and CH4 are not affected by the gibbsite/siloxane structure or water content. However, the siloxane pores have a better selective storage capacity for H2 from the H2/CH4 mixture. The existence of water in the formation weakens both the H2 and CH4 storage densities. For gibbsite pores, the water molecules form a film on the surface, driving the H2 and CH4 molecules to the middle of the pore. But for siloxane pores, the water molecules form water cluster across the pore, leaving less pore volumes for H2 and CH4 storage, which causes a weaker H2 storage capacity than that of the gibbsite pores.

2.
Clin. transl. oncol. (Print) ; 25(7): 2138-2152, jul. 2023. graf
Artigo em Inglês | IBECS | ID: ibc-222384

RESUMO

Purpose The hypoxic tumor microenvironment and the maintenance of stem cells are relevant to the malignancy of prostate cancer (PCa). However, whether HIF-1α in the hypoxic microenvironment mediates the transformation of prostate cancer to a stem cell phenotype and the mechanism have not been elucidated.Materials and methods Prostate cancer stem cells (PCSCs) from PC-3 cell lines were examined for the expression of CD44, CD133, ALDH1, HIF-1α, Notch1, and HES1. We observed the effect of knockdown HIF-1α in vitro and mice models and evaluated the impact of HIF-1α on the Notch1 pathway as well as stem cell dedifferentiation. The effects on sphere formation, cell proliferation, apoptosis, cell cycle, and invasive metastasis were evaluated. Results In our study, hypoxia upregulated HIF-1α expression and induced a stem cell phenotype through activation of the Notch1 pathway, leading to enhanced proliferation, invasion, and migration of PCa PC-3 cells. The knockdown of HIF-1α significantly inhibited cell dedifferentiation and the ability to proliferate, invade and metastasize. However, the inhibitory effect of knocking down HIF-1α was reversed by Jagged1, an activator of the Notch1 pathway. These findings were further confirmed in vivo, where hypoxia could enhance the tumorigenicity of xenograft tumors by upregulating the expression of HIF-1α to activate the Notch1 pathway. In addition, the expression of HIF-1α and Notch1 was significantly increased in human PCa tissues, and high expression of HIF-1α correlated with the malignancy of PCa. Conclusion In a hypoxic environment, HIF-1α promotes PCa cell dedifferentiation to stem-like cell phenotypes by activating the Notch1 pathway and enhancing the proliferation and invasive capacity of PC-3 cells (AU)


Assuntos
Animais , Masculino , Camundongos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neoplasias da Próstata/patologia , Hipóxia Celular/fisiologia , Linhagem Celular Tumoral , Células-Tronco Neoplásicas/patologia , Transdução de Sinais , Microambiente Tumoral , Fenótipo
3.
Clin Transl Oncol ; 25(7): 2138-2152, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36757381

RESUMO

PURPOSE: The hypoxic tumor microenvironment and the maintenance of stem cells are relevant to the malignancy of prostate cancer (PCa). However, whether HIF-1α in the hypoxic microenvironment mediates the transformation of prostate cancer to a stem cell phenotype and the mechanism have not been elucidated. MATERIALS AND METHODS: Prostate cancer stem cells (PCSCs) from PC-3 cell lines were examined for the expression of CD44, CD133, ALDH1, HIF-1α, Notch1, and HES1. We observed the effect of knockdown HIF-1α in vitro and mice models and evaluated the impact of HIF-1α on the Notch1 pathway as well as stem cell dedifferentiation. The effects on sphere formation, cell proliferation, apoptosis, cell cycle, and invasive metastasis were evaluated. RESULTS: In our study, hypoxia upregulated HIF-1α expression and induced a stem cell phenotype through activation of the Notch1 pathway, leading to enhanced proliferation, invasion, and migration of PCa PC-3 cells. The knockdown of HIF-1α significantly inhibited cell dedifferentiation and the ability to proliferate, invade and metastasize. However, the inhibitory effect of knocking down HIF-1α was reversed by Jagged1, an activator of the Notch1 pathway. These findings were further confirmed in vivo, where hypoxia could enhance the tumorigenicity of xenograft tumors by upregulating the expression of HIF-1α to activate the Notch1 pathway. In addition, the expression of HIF-1α and Notch1 was significantly increased in human PCa tissues, and high expression of HIF-1α correlated with the malignancy of PCa. CONCLUSION: In a hypoxic environment, HIF-1α promotes PCa cell dedifferentiation to stem-like cell phenotypes by activating the Notch1 pathway and enhancing the proliferation and invasive capacity of PC-3 cells.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia , Próstata , Neoplasias da Próstata , Animais , Humanos , Masculino , Camundongos , Hipóxia Celular/fisiologia , Linhagem Celular Tumoral , Hipóxia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Células-Tronco Neoplásicas/patologia , Neoplasias da Próstata/patologia , Transdução de Sinais , Microambiente Tumoral
4.
Bioresour Technol ; 340: 125654, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34332448

RESUMO

A novel experimental method based on the combination of bio-oil composition inversion and function fitting was purposed and verified for describing the componential evolution curves during the liquefaction of biomass pyrolysis vapors. The evolution curves of representative condensable components were fitted by linear and Slogistic function in the short, middle and long three condensing fields. Linear function exhibited a significant effectiveness for the description and prediction of low-boiling water and furfural and the relative deviations were no more than 5% between actual values in long condenser and predictive values from the elongation of curves in short and middle condensers. For high-boiling phenolic compounds, linear function failed to fit their evolutions in long condenser but Slogistic fitting remained effective despite the relative deviation increasing to about 10%. This investigation provided a unique and effective prediction method for the vapor evolution in industrial shell and tube heat exchanger according to laboratory-scale experiment.


Assuntos
Temperatura Alta , Pirólise , Biocombustíveis , Biomassa , Gases
5.
Medicine (Baltimore) ; 100(3): e24068, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33546009

RESUMO

ABSTRACT: Currently, the combination of 5-fluorouracil, leucovorin, irinotecan, and oxaliplatin (FOLFIRINOX) is the standard therapy for metastatic pancreatic cancer. In recent years, FOLFIRINOX-based neoadjuvant therapy for locally advanced pancreatic cancer (LAPC) has been gaining an increasing amount of attention, owing to its ability to reduce disease stage and transform LAPC to borderline resectable or even resectable pancreatic cancer. Accordingly, we aimed to evaluate the efficacy of first-line FOLFIRINOX chemotherapy in patients with LAPC.We searched PubMed, Embase, and Cochrane Library from the time of establishment till January 1, 2020 and included studies focusing on LAPC patients who received FOLFIRINOX as first-line neoadjuvant treatment. The primary outcomes were: resection rate and radical (R0) resection rate while the secondary outcomes were: objective response rate, overall survival, progression-free survival, and rate of grade 3 to 4 adverse events. The meta package for R 3.6.2 was used for heterogeneity and publication bias testing.Twenty-one studies, including 653 patients with LAPC, were selected. After treatment with FOLFIRINOX, the resection rate was 26% (95% confidence interval [CI] = 20%-32%, I2 = 61%) and R0 resection rate was 88% (95% CI = 78%-95%, I2 = 62%). The response rate was 34% (95% CI = 25%-43%, I2 = 56%). The median overall survival and progression-free survival durations ranged from 10.0 to 32.7 months and 3.0 to 25.3 months, respectively. The observed grade 3 to 4 adverse events were neutropenia (20.0 per 100 patients, 95% CI = 14%-27%, I2 = 75%), febrile neutropenia (7.0 per 100 patients, 95% CI = 5%-9%, I2 = 42%), thrombocytopenia (6.0 per 100 patients, 95% CI = 5%-8%, I2 = 27%), nausea/vomiting (7.0 per 100 patients, 95% CI = 7%-12%, I2 = 76%), diarrhea (10.0 per 100 patients, 95% CI = 8%-12%, I2 = 38%), and fatigue (9.0 per 100 patients, 95% CI = 7%-11%, I2 = 43%).FOLFIRINOX-based neoadjuvant chemotherapy has the potential to improve the rates of resection, R0 resection, and median OS in LAPC. Our results require further validation in large, high-quality randomized controlled trials.


Assuntos
Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica , Terapia Neoadjuvante , Neoplasias Pancreáticas/tratamento farmacológico , Fluoruracila/uso terapêutico , Humanos , Irinotecano/uso terapêutico , Leucovorina/uso terapêutico , Oxaliplatina/uso terapêutico , Neoplasias Pancreáticas/cirurgia
6.
Bioresour Technol ; 309: 123360, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32305013

RESUMO

In this study, the CO2 co-gasification characteristics of pyrolytic oil distillation residue and biochar under different reaction temperatures were investigated by thermogravimetric analyzer (TGA). The influence of blend ratio on co-gasification synergy was adequately characterized by correlating the evolution of chemical structure and active AAEMs. The results indicated that increasing proportion of pyrolytic oil distillation residue could effectively improve gasification reactivity of biochar and enhance synergistic behaviors during co-gasification process, whereas the raising reaction temperature dwindled the enhancement of co-gasification reactivity and mutual promotion between individual samples. Moreover, three gasification kinetic models suggested that the lowest apparent activation energy (181.49~182.72 kJ/mol) among blends was obtained by 70 wt% additions of pyrolytic oil distillation residue. Furthermore, the results of Raman and ICP-AES analysis well related to the co-gasification synergy. The migration of active AAEMs and evolution of carbon structure had a pronounced influence on synergistic effect as co-gasification reaction progressed.


Assuntos
Carvão Vegetal , Destilação , Biomassa , Dióxido de Carbono , Cinética , Temperatura
7.
Bioresour Technol ; 285: 121370, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31022576

RESUMO

The effect of condensing temperature on composition of bio-oil obtained via fractional condensation was investigated by pyrolysis-condensation experiments of walnut shells at condensing temperatures from 290 K to 370 K. The condensing efficiency of the first stage condenser decreased from 0.59 to 0.12 with increasing temperature. Moisture of bio-oil decreased from 40% to 5%, but the C/O ratio increased from 0.50 to 1.50. Compared with contents observed at the lowest condensation temperature, the maximum content of each component increased by 50%-500%. Combined with variations in condensing efficiency and composition content, the optimum condensing temperature range for declining water in bio-oil was 340-350 K. The condensing temperature associated with the enrichment of acetic acid and furfural was 345 K. The 355 K optimum condensing temperature could be selected to achieve the maximum enrichment of guaiacol and its derivatives.


Assuntos
Biocombustíveis , Juglans , Biomassa , Temperatura Alta , Óleos de Plantas , Polifenóis , Pirólise , Temperatura
8.
Artigo em Inglês | MEDLINE | ID: mdl-26989425

RESUMO

Woad root has been used for the prevention of influenza for hundreds of years in many Asian countries. In this study, the antiviral modes of clemastanin B (CB), epigoitrin, phenylpropanoid portion (PEP), and the mixture of phenylpropanoids, alkaloids, and organic acid portions (PEP + ALK + OA) from wood root extract against influenza virus A FM1 were investigated. The results revealed that CB, epigoitrin, PEP, and PEP + ALK + OA exert their anti-influenza activity via inhibiting the virus multiplication, prophylaxis, and blocking the virus attachment. The primary mode of action of PEP and PEP + ALK + OA is the inhibition of virus replication. The inhibitory effect on virus attachment and multiplication is the main modes for epigoitrin. All the compounds or chemical portions from woad root extract tested in this study do not have direct virucidal activity. Our results provided the comprehensive analysis of the antiviral mechanism of wood root extract.

9.
J Colloid Interface Sci ; 460: 281-9, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26364074

RESUMO

The adsorption and desorption of Kr on graphite at temperatures in the range 60-88K, was systematically investigated using a combination of several simulation techniques including: Grand Canonical Monte Carlo (GCMC), Canonical kinetic-Monte Carlo (C-kMC) and the Mid-Density Scheme (MDS). Particular emphasis was placed on the gas-solid, gas-liquid and liquid-solid 2D phase transitions. For temperatures below the bulk triple point, the transition from a 2D-liquid-like monolayer to a 2D-solid-like state is manifested as a sub-step in the isotherm. A further increase in the chemical potential leads to another rearrangement of the 2D-solid-like state from a disordered structure to an ordered structure that is signalled by (1) another sub-step in the monolayer region and (2) a spike in the plot of the isosteric heat versus density at loadings close to the dense monolayer coverage concentration. Whenever a 2D transition occurs in a grand canonical isotherm it is always associated with a hysteresis, a feature that is not widely recognised in the literature. We studied in details this hysteresis with the analysis of the canonical isotherm, obtained with C-kMC, which exhibits a van der Waals (vdW) type loop with a vertical segment in the middle. We complemented the hysteresis loop and the vdW curve with the analysis of the equilibrium transition obtained with the MDS, and found that the equilibrium transition coincides exactly with the vertical segment of the C-kMC isotherm, indicating the co-existence of two phases at equilibrium. We also analysed adsorption at higher layers and found that the 2D-coexistence is also observed, provided that the temperature is well below the triple point. Finally the 2D-critical temperatures were obtained for the first three layers and they are in good agreement with the experimental data in the literature.

10.
J Cell Sci ; 127(Pt 20): 4396-408, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25107366

RESUMO

Mutations in CFTR lead to dysfunction of tubular organs, which is currently attributed to impairment of its conductive properties. We now show that CFTR regulates tight junction assembly and epithelial cell differentiation through modulation of the ZO-1-ZONAB pathway. CFTR colocalizes with ZO-1 at the tight junctions of trachea and epididymis, and is expressed before ZO-1 in Wolffian ducts. CFTR interacts with ZO-1 through the CTFR PDZ-binding domain. In a three-dimensional (3D) epithelial cell culture model, CFTR regulates tight junction assembly and is required for tubulogenesis. CFTR inhibition or knockdown reduces ZO-1 expression and induces the translocation of the transcription factor ZONAB (also known as YBX3) from tight junctions to the nucleus, followed by upregulation of the transcription of CCND1 and downregulation of ErbB2 transcription. The epididymal tubules of cftr(-/-) and cftr(ΔF508) mice have reduced ZO-1 levels, increased ZONAB nuclear expression, and decreased epithelial cell differentiation, illustrated by the reduced expression of apical AQP9 and V-ATPase. This study provides a new paradigm for the etiology of diseases associated with CFTR mutations, including cystic fibrosis.


Assuntos
Núcleo Celular/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Fibrose Cística/metabolismo , Proteínas de Ligação a DNA/metabolismo , Células Epiteliais/fisiologia , Junções Íntimas/fisiologia , Fatores de Transcrição/metabolismo , Proteína da Zônula de Oclusão-1/metabolismo , Animais , Diferenciação Celular/genética , Células Cultivadas , Ciclina D1/genética , Ciclina D1/metabolismo , Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Proteínas de Ligação a DNA/genética , Regulação da Expressão Gênica/genética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Organogênese/genética , Ligação Proteica , Transporte Proteico/genética , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Transdução de Sinais/genética , Fatores de Transcrição/genética , Proteína da Zônula de Oclusão-1/genética
11.
PLoS One ; 6(5): e19120, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21625623

RESUMO

Cystic fibrosis (CF) is the most common life-limiting recessive genetic disease among Caucasians caused by mutations of the cystic fibrosis transmembrane conductance regulator (CFTR) with over 95% male patients infertile. However, whether CFTR mutations could affect spermatogenesis and result in azoospermia remains an open question. Here we report compromised spermatogenesis, with significantly reduced testicular weight and sperm count, and decreased cAMP-responsive element binding protein (CREB) expression in the testes of CFTR knockout mice. The involvement of CFTR in HCO(3) (-) transport and the expression of the HCO(3) (-) sensor, soluble adenylyl cyclase (sAC), are demonstrated for the first time in the primary culture of rat Sertoli cells. Inhibition of CFTR or depletion of HCO(3) (-) could reduce FSH-stimulated, sAC-dependent cAMP production and phosphorylation of CREB, the key transcription factor in spermatogenesis. Decreased CFTR and CREB expression are also observed in human testes with azoospermia. The present study reveals a previously undefined role of CFTR and sAC in regulating the cAMP-CREB signaling pathway in Sertoli cells, defect of which may result in impaired spermatogenesis and azoospermia. Altered CFTR-sAC-cAMP-CREB functional loop may also underline the pathogenesis of various CF-related diseases.


Assuntos
Azoospermia/etiologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/fisiologia , Fibrose Cística/patologia , Espermatogênese/fisiologia , Adenilil Ciclases/metabolismo , Adulto , Animais , Azoospermia/metabolismo , Azoospermia/patologia , Bicarbonatos/metabolismo , Western Blotting , AMP Cíclico/metabolismo , Fibrose Cística/metabolismo , Modelos Animais de Doenças , Imunofluorescência , Humanos , Técnicas Imunoenzimáticas , Masculino , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , Fosforilação , Ratos , Ratos Sprague-Dawley , Células de Sertoli/metabolismo , Células de Sertoli/patologia , Adulto Jovem
12.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 24(2): 119-21, 2008 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-18237525

RESUMO

AIM: To explore the biological effect of (60)Cogamma ray on alveolar type II cells and interstitial cells of alveoliar septum. METHODS: Alveolar type II cells(AT-II) and interstitial cells including interstitial macrophages and fibroblasts were irradiated by 0, 3, 5, 7 Gy of gamma ray respectively. The effect of irradiation on AT-II proliferation was observed by argentation against nucleus. The activity of MMP-2, -9 in supernatants from AT-II and interstitial cells after irradiation was determined by zymography. The levels of TGF-beta1 and collagen type IV in supernatant from interstitial cells after irradiation were measured by ELISA. RESULTS: The nucleolus number of AT-II was increased with the increase of irradiation dose and group 7 Gy reached the highest level. The activity of MMP-2, -9 in supernatant from AT-II after irradiation increased at first and then decreased gradually. The activity of MMP-2, -9 and the content of TGF-beta1 in interstitial cells increased step by step, but collagen type IV decreased at first and then increased. CONCLUSION: AT-II, macrophages and fibroblasts are all involved in pulmonary invalid remodeling course in early radiation pulmonary injury, which is related to the initiation of pulmonary fibrosis in late period.


Assuntos
Células Epiteliais Alveolares/metabolismo , Células Epiteliais Alveolares/efeitos da radiação , Radioisótopos de Cobalto/efeitos adversos , Raios gama/efeitos adversos , Lesão Pulmonar/patologia , Alvéolos Pulmonares/metabolismo , Alvéolos Pulmonares/efeitos da radiação , Animais , Células Cultivadas , Colágeno Tipo IV/metabolismo , Ensaio de Imunoadsorção Enzimática , Fibroblastos/metabolismo , Fibroblastos/efeitos da radiação , Lesão Pulmonar/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Alvéolos Pulmonares/citologia , Ratos , Ratos Wistar , Fator de Crescimento Transformador beta1/metabolismo
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