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1.
Int Immunopharmacol ; 105: 108555, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35121223

RESUMO

Today, it is well-known that the interactions and secretion within the tumour are crucial to consider for cancer therapy. Some novel cancer therapy modalities such as immunotherapy or tumour vaccination therapy work based on the control of interactions within the tumour microenvironment (TME). It has been revealed that anti-cancer drugs or radiotherapy can modulate some interactions in favour of cancer therapy. However, they may induce some mechanisms to increase the resistance of cancer cells to therapy. Paclitaxel is known as the first approved herbal derived chemotherapy drug. Although the main known anti-cancer effect of paclitaxel is the inhibition of the cell cycle, today, it has been well known that paclitaxel may suppress the tumour via modulating several interactions in TME. Furthermore, paclitaxel may increase the expression of some tumour resistance drivers. This review aims to discuss the interactions within TME following treatment with paclitaxel. The effects of paclitaxel on the anti-tumour immunity, immunosuppressive cells, hypoxia, and also angiogenesis will be discussed. The targeting of these interactions may be interesting to increase therapy efficiency using the combination modalities.


Assuntos
Antineoplásicos , Neoplasias , Antineoplásicos/uso terapêutico , Humanos , Imunoterapia , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Microambiente Tumoral
2.
ACS Omega ; 6(23): 14765-14773, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34151058

RESUMO

N-methyl-2-pyrrolidone (NMP), pyridine (Py), tetrahydrofuran (THF), and tetralin (THN) were used to swell Hefeng acid-washed bituminous coal (HBCAC). The swelling effect on HBCAC by each solvent is different, among which NMP presented well swelling performance, with a swelling degree of 2.11. FTIR results showed that acid washing and swelling processes presented a marginal effect on HBC, and there was no damage to the macromolecule structure of the coal. TG-DTG profiles of the swollen coals illustrated that the total weight loss of each sample was lower than that of the acid-washing one, while the temperature of the maximum weight loss rate peak was almost unchanged, around 445 °C. Extract yield by methanol followed the order of HBCAC > HBC > HBCAC-NMP (swelled by NMP), showing that acid washing promoted the methanol extraction process, with a higher extract yield of 3.21%, which is twice that of HBC (1.66%).

3.
ACS Omega ; 6(12): 8288-8296, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33817488

RESUMO

Hydrodynamic cavitation (HC) of aromatic hydrocarbons present in creosote oil obtained from coal tar in the presence of 0.3% (w/w) Ni2+ as an inducer increased its naphthalene and phenanthrene content by 7.3 and 2.6%, respectively. An optimal procedure was developed based on the use of an upstream pressure of 2.6 MPa, an immersing height (H) for the cavitator of 105 mm, 10% H2O content, use of a NiSO4 solution at pH 4.0, and an operating temperature of 75 °C. Enrichment of the naphthalene and phenanthrene components is caused by hydroxyl and hydrogen radicals generated in the reaction inducing aromatic components to undergo a series of radical demethylation/methylation reactions to produce new product ratios. The observed increases in naphthalene and phenanthrene content using Ni2+ as a radical inducer are in contrast with the previous results using Fe2+ under similar conditions, which led to the enrichment of the acenaphthalene fraction of creosote oil.

4.
Rapid Commun Mass Spectrom ; 34(20): e8887, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-32656863

RESUMO

RATIONALE: Gas chromatography/mass spectrometry (GC/MS) and high-performance liquid chromatography/time-of-flight mass spectrometry (HPLC/TOF-MS) were used to separate and reveal the molecular characteristics of organic matter in low-rank coals. METHODS: Six soluble portions (SPs) were obtained by sequential thermal dissolution (TD) of two low-rank coals in the order of cyclohexane, acetone and methanol solvents at 300°C. Organic matter with different molecular characteristics were enriched in eachTD extract, which was further separated and analyzed by GC/MS and HPLC/TOF-MS using an electrospray ionization source in positive mode to obtain a comprehensive understanding of the structural composition of coals. RESULTS: Low polarity compounds like alkanes and arenes have a better solubility in cyclohexane. Phorone has the highest relative abundance in the acetone SPs, and the main compounds detected in the methanol SPs are alcohols and phenols. According to the data from HPLC/TOF-MS, most of the oxygen atoms are in the form of carbonyl and alkoxy groups. The nitrogen-containing compounds in SPs are mainly saturated aliphatic amines and pyridines. The sulfur-containing compounds mainly exist in the form of thioalkanes and thiophenes. CONCLUSIONS: Non-destructive methods were used to obtain soluble matter from coals, and different chromatographic and mass spectrometric techniques were used to separate and analyze the organic matter in coals. Detailed molecular structural information was obtained for the efficient and clean utilization of low-rank coals.

5.
Rapid Commun Mass Spectrom ; 33(13): 1107-1113, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-30941795

RESUMO

RATIONALE: Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) was applied to the characterization of organic compounds in coal extracts at the molecular level. Large volumes of data obtained by FT-ICR MS were processed via statistical methods to extract valuable information on the molecular structures and compositions of organic compounds in coal. METHODS: A low-rank coal was subjected to ultrasonic extraction sequentially with six solvents to separate and enrich species with different molecular characteristics. Complex mass spectra of the six extracts were obtained by a FT-ICR MS system equipped with two ionization sources. Two multivariate statistical methods, hierarchical clustering analysis (HCA) and principle component analysis (PCA), were introduced to mine useful information from the complex MS data and visually exhibit comprehensive molecular details in coal extracts. RESULTS: Similarities and differences between the 17 MS data sets from six coal extracts ionized by different ion sources were visually exhibited in plots via data processing using HCA and PCA. For HCA, all of the identified compounds were divided into seven classes (CH, O, N, S, ON, OS, and NS), and detailed differences in the relative abundance were revealed. In addition, PCA discriminated the differences in molecular composition for organic compounds from the six extracts. CONCLUSIONS: Multivariate statistical analysis is a promising methodology which can interpret the chemical composition of coals and coal derivatives at the molecular level, especially for the analysis of multiple complex samples presenting in a single plot.

6.
Rapid Commun Mass Spectrom ; 32(16): 1462-1472, 2018 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-29740899

RESUMO

RATIONALE: Gas chromatography/mass spectrometry (GC/MS) is a routine and basic instrumental method for the analysis of complex coal conversion products in the chemical industry. To further enhance the practical potential of GC/MS in chemical industry, a tandem MS method for the selection of ion pairs applied in monitoring coal conversions was established using GC/quadrupole time-of-flight MS (GC/Q-TOF MS). The corresponding fragmentation pathways were explored and suitable ion pairs were screened. METHODS: Fourteen coal-related model compounds (CRMCs) were analyzed using GC/Q-TOF MS with different collision-induced dissociation (CID) energies (5-20 eV). The fragmentation pathways can offer a better understanding of chemical bond breaking, hydrogen transfer, rearrangement reactions and elimination of neutral fragments for CRMCs during the CID process. RESULTS: The precursor ions of aromatic hydrocarbons without alkyl chains were difficult to fragment with a CID energy of 20 eV. But aromatic hydrocarbons with branched chains were prone to fragment via the loss of alkyl chains and further fragmented through ring-opening reactions. Compared with the Calk Car bond, the Car Car bond was difficult to fragment due to its high bond dissociation energy. The existence of heteroatoms facilitated fragmentation that was conducive to the screening of ion pairs. CONCLUSIONS: The CID technique of GC/Q-TOF MS will contribute to studies on the organic composition of coals and to building monitoring methods for coal conversions via fragmentation and ion pair selection.

7.
Ying Yong Sheng Tai Xue Bao ; 27(8): 2438-2444, 2016 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-29733129

RESUMO

The research aimed to study the characteristic of ionic homeostasis of annual seedlings of Populus ×euramericanna under irrigation with non-magnetized and magnetized 0 or 4.0 g·L-1 NaCl solution for 30 days in the growing season. The ion contents of K+, Na+, Ca2+ and Mg2+ in the lea-ves and roots were measured by atomic absorption spectrophotometry (AAS). The ion homeostasis coefficient (K) and the ion selective transport coefficient (SXi,Na) from root system to leaves were analyzed. Compared with the unsalted treatment, the ion contents of Na+ and Ca2+, SK,Na and SMg,Na increased in leaves and roots under NaCl stress, while the K+ and Mg2+ ion content, the ratio of K+/Na+ and SCa,Na decreased. Compared with the non-magnetized NaCl solution (NM), the magnetized NaCl solution (M) made leaves and roots maintain lower content of Na+ but higher content of K+ and the K+/Na+. Compared with the NM, the content of Ca2+ decreased while that of Mg2+ increased in the M. In M, K was higher than that in NM, and there was significant increase in the leaves than that in the roots. The ratios of SK,Na and SMg,Na in leaves and roots in M were higher than those in NM, while the ratio of SCa,Na was lower. The magnetized NaCl solution decreased Na+ content, increased K+, Ca2+ and Mg2+ content, and maintained higher K+/Na+, which was beneficial for the physiological metabolism of the whole plant. So, the magnetic effect could promote the re-establishment of ionic homeostasis by ions selective absorption and transportation under NaCl stress.


Assuntos
Irrigação Agrícola , Magnetismo , Populus/química , Águas Salinas , Cálcio , Homeostase , Íons , Magnésio , Folhas de Planta/química , Raízes de Plantas/química , Potássio , Plântula , Sódio , Cloreto de Sódio , Estresse Fisiológico
8.
J Huazhong Univ Sci Technolog Med Sci ; 33(3): 339-345, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23771657

RESUMO

Previous studies have shown that STAT3 plays a vital role in the genesis and progression of cancer. In this study, we investigated the relationship between the JAK2/STAT3 signalling pathway and germacrone-induced apoptosis in HepG2 cells. HepG2 cells were incubated with germacrone for 24 h, the protein expression of p-STAT3, STAT3, p-JAK2 and JAK2 was detected by Western Blotting, and RT-PCR was used to determine the expression of STAT3, p53, Bcl-2 and Bax at transcriptional levels. Besides that, HepG2 cells were pre-treated with AG490 or IL-6 for 2 h, and then incubated with germacrone for 24 h. The expression of p-JAK2, JAK2, p-STAT3, STAT3, p53, Bax and Bcl-2 was detected by Western blotting. The activity of HepG2 cells was tested by MTT assay. The apoptosis of HepG2 cells and levels of reactive oxygen species (ROS) were flow cytometrically measured. The results showed that germacrone exposure decreased p-STAT3 and p-JAK2 and regulated expression of p53 and Bcl-2 family members at the same time. Moreover, IL-6 enhanced the activation of the JAK2/STAT3 signalling pathway and therefore attenuated the germacrone-induced apoptosis. Suppression of JAK2/STAT3 signalling pathway by AG490, an inhibitor of JAK2, resulted in apoptosis and an increase in ROS in response to germacrone exposure. We therefore conclude that germacrone induces apoptosis through the JAK2/STAT3 signalling pathway.


Assuntos
Apoptose/efeitos dos fármacos , Medicamentos de Ervas Chinesas/administração & dosagem , Janus Quinase 2/metabolismo , Fator de Transcrição STAT3/metabolismo , Sesquiterpenos de Germacrano/administração & dosagem , Transdução de Sinais/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células Hep G2 , Humanos
9.
Zhonghua Xin Xue Guan Bing Za Zhi ; 37(5): 422-5, 2009 May.
Artigo em Chinês | MEDLINE | ID: mdl-19781218

RESUMO

OBJECTIVE: To compare the characterization of coronary atherosclerotic plaques in patients with unstable angina pectoris (UAP) and stable angina pectoris (SAP) by optical coherence tomography (OCT). METHODS: OCT was performed in 47 patients (23 UAP and 24 SAP) undergoing coronary angiography. Lipid-rich plaque (defined by > or = 2 quadrants of the cross-section area), thin cap fibroatheroma (TCFA), thickness of fibrous cap, plaque rupture, calcification and thrombus visualized by OCT were compared between UAP and SAP patients. RESULTS: OCT imaging was successfully in 44 out of 47 patients (22 UAP, 22 SAP). Proportion of lipid-rich plaques was similar between UAP and SAP groups [91% (20/22) vs. 73% (16/22), P = 0.741]. The minimum thickness of fibrous cap in the UAP group was significantly thinner than that in SAP group [(69.5 +/- 34.7) microm vs. (141.1 +/- 68.5) microm, P = 0.000] and the rate of fibrous cap erosion in the UAP group was significantly higher than that in the SAP group [59% (13/22) vs. 9% (2/22), P = 0.000]. Percents of TCFA [73% (16/22) vs. 14% (3/22), P = 0.000] and plaque rupture [50% (11/22) vs. 9% (2/22), P = 0.003] were significantly higher in UAP group compared those in SAP group. Incidence of thrombus and calcification were similar between two groups. CONCLUSIONS: OCT imaging can clearly define plaque characterization of coronary atherosclerosis. UAP patients have thinner fibrous cap, higher incidences of fibrous cap erosion, plaque rupture and TCFA compared patients with SAP.


Assuntos
Angina Pectoris/diagnóstico por imagem , Angina Instável/diagnóstico por imagem , Doença da Artéria Coronariana/diagnóstico por imagem , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia , Estudos Retrospectivos , Tomografia de Coerência Óptica
10.
Zhonghua Xin Xue Guan Bing Za Zhi ; 36(3): 223-8, 2008 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-19099978

RESUMO

OBJECTIVE: To observe the diagnostic value of non-invasive 128-slice computed tomography coronary angiography (CTA) in comparison with invasive coronary angiography. METHODS: 128-slice CTA and invasive coronary angiography were performed in 78 unselected consecutive patients (63 patients with suspected coronary artery disease and 15 patients with previous coronary stenting, 56 males, mean age 61 +/- 10 years) and > 50% reduction of minimal lumen diameter was defined as significant coronary stenosis. RESULTS: Fifty-eight out of 879 segments (7%) from CTA were not assessable because of irregular rhythm, vessel calcification or tachycardia. Compared with invasive coronary angiography, segment-based analysis from the 821 segments showed the sensitivity by CTA was 87%, specificity 97%, PPV 83% and NPV 97%. Four out of 22 stents implanted in 15 patients were not assessable by CTA because of poor image quality. Compared with invasive coronary angiography, the sensitivity of diagnosing in-stent restenosis by CTA was 100%, specificity 77%, PPV 63% and NPV 100% for the remaining 18 stents. CONCLUSIONS: One hundred and twenty-eight-slice CTA has a high accuracy for detecting coronary artery disease and in-stent restenosis after coronary stenting and could be considered as a valuable noninvasive technique for screening coronary artery disease in suspected patients.


Assuntos
Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Tomografia Computadorizada Espiral/métodos , Adulto , Idoso , Doença da Artéria Coronariana/diagnóstico , Estenose Coronária/diagnóstico , Estenose Coronária/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
12.
Zhonghua Yi Xue Za Zhi ; 86(16): 1102-6, 2006 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-16796834

RESUMO

OBJECTIVE: To compare neointimal proliferation of drug-eluting stent (DES) with bare mental stent (BMS) by optical coherence tomography (OCT). METHODS: OCT images were obtained in 21 diseased coronary vessels with 23 stents in 19 patients with coronary artery disease at 5 - 93 months post DES or BMS stents. Twenty-two stents of all 23 stents were divided into three groups. Nine DES stents at 6 - 10 months post stenting were considered as group A, 8 BMS stents at 5 - 10 months post stenting as group B, and 5 BMS stents at 23 - 93 months post stenting as group C. OCT images were quantitatively analyzed to compare neointimal proliferation of three groups after stenting. RESULTS: All 21 vessels and 23 stents OCT images were successfully acquired. The maximal neointima, luminal loss in diameter and cross sectional area (CSA), and restenosis in diameter and CSA were significantly statistically different within three groups. The maximal intimal proliferations post stenting in group A were significantly lower than group B (0.20 mm +/- 0.13 mm vs 0.81 mm +/- 0.46 mm, P = 0.019) or group C (0.91 mm +/- 0.27 mm, P = 0.007), luminal loss of diameter in group A were significantly lower than group B (0.27 mm +/- 0.17 mm vs 1.12 mm +/- 0.79 mm, P = 0.009) or group C (1.20 mm +/- 0.31 mm, P = 0.013), restenosis rates in diameter in group A were significantly less than group B (8.90% +/- 4.47% vs 36.36% +/- 24.34%, P = 0.009) or group C (35.48 +/- 6.09, P = 0.017), luminal loss in CSA in group A were lower than group B (1.14 mm(2) +/- 0.9 mm(2) vs 3.96 mm(2) +/- 2.62 mm(2), P = 0.009) or group C (4.66 mm(2) +/- 1.66 mm(2), P = 0.006), and restenosis rates in CSA in group A were less than group B (15.43% +/- 7.89% vs 48.14% +/- 30.43%, P = 0.017) or group C (55.20% +/- 11.24%, P = 0.009). Almost all surfaces of 13 BMS stent struts were covered by significant neointimal coverage, surfaces of 10 DES struts were less significantly neointimal coverage, and some surfaces of DES struts were uncovered with neointima even at 29 months post stenting. CONCLUSION: OCT imaging can clearly visualize stent struts and neointimal formation of strut surfaces post DES or BMS stenting, and this new imaging modality will play important role in evaluating the efficacy of drug-eluting stent.


Assuntos
Doença das Coronárias/terapia , Stents Farmacológicos , Stents , Tomografia de Coerência Óptica/métodos , Túnica Íntima/patologia , Adulto , Idoso , Doença das Coronárias/patologia , Feminino , Seguimentos , Humanos , Masculino , Metais , Pessoa de Meia-Idade , Fatores de Tempo , Resultado do Tratamento
13.
Zhonghua Xin Xue Guan Bing Za Zhi ; 34(2): 130-3, 2006 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-16626579

RESUMO

OBJECTIVE: To evaluate coronary artery atherosclerotic plaque characteristics and changes post coronary stenting by optical coherence tomography (OCT). METHODS: OCT images were obtained in 22 diseased coronary vessels after coronary angiography or percutaneous coronary interventions (PCI) in 20 patients and in 23 stents [7 sirolimus-eluting stents (SES) follow up at 4-29 months post stenting and 8 bare mental stents (BMS) at 4-35 months post stenting, 8 stents immediately after PCI]. RESULTS: All 22 vessels and 23 stents OCT images were successfully acquired. Two thromboses, 8 fibrous, 9 lipid-rich and 3 calcium plaques as well as 3 plaque ruptures were visualized by OCT. No significant neointimal proliferation and restenosis were found in SES stents and some struts were not covered with neointima even at 29 months post stenting. Significant neointimal proliferation on surfaces of stent struts were visualized in all 8 BMS stents and restenosis was detected in 3 BMS stents. OCT images obtained immediately after PCI showed that 3 stents were well positioned, tissue prolapse between coronary stent struts occurred in 4 stents and stent dissociation with vessel wall could be seen in 1 stent. CONCLUSIONS: OCT imaging can clearly visualize different types of atherosclerotic plaques. By providing detailed information on plaque characteristics, this technique might help cardiologists in choosing suitable stents and guiding preventive therapy for patients with coronary heart disease.


Assuntos
Doença das Coronárias/diagnóstico por imagem , Doença das Coronárias/terapia , Tomografia de Coerência Óptica , Adulto , Idoso , Stents Farmacológicos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia , Sirolimo/administração & dosagem , Stents
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