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1.
Pharmacol Res ; 151: 104519, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31706011

RESUMEN

Silybin (SB) is widely used to treat chronic liver diseases, especially this compound is much efficient for the treatments of alcoholic and non-alcoholic steatohepatitis (NASH). However, low bioavailability seriously limits wide-application of SB in biomedical niche. Prior to this study, we found that tangeretin (TG) could remarkably increase the bioavailability of SB by the inhibition of efflux transporters, which encourges us to therapeutical discovery of SB and TG combitional use against NASH. Here, we revealed that TG is capable of improving hepatic-protective activity of SB in mice with NASH by interfering liver oxidative stress, inflammation, and lipid accumulation. In addition, TG was observed to enhance the exposural level of SB in the plasma and liver of mice. Our metabolome assay confirmed that amino acid metabolism and lipid biosynthesis mostly accounted for combitional use of SB and TG to teat NASH in mice, basically biosynthesis of unsaturated fatty acids was mostly affected. Notably, significant inhibitions in fatty acid generating and transporting proteins such as G6PD, FABP4, LPL and CD36/FAT, and cholesterol metabolism enzyme CYP27A1 as well as nuclear transcription factors FXR, PPAR-γ, and LXR were illustrated to decipher therapeutic mechanisms of SB and TG against experimental NASH. Taken together, the strategy based combitional use of SB and TG has a potential-capacity to treat NASH.


Asunto(s)
Flavonas/uso terapéutico , Metabolismo de los Lípidos/efectos de los fármacos , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Sustancias Protectoras/uso terapéutico , Silibina/uso terapéutico , Animales , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Estrés Oxidativo/efectos de los fármacos
2.
Front Oncol ; 12: 978603, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36132133

RESUMEN

Ovarian cancer (OC) has the greatest mortality rate among gynecological cancers, with a five-year survival rate of <50%. Contemporary adjuvant chemotherapy mostly fails in the case of OCs that are refractory, metastatic, recurrent, and drug-resistant. Emerging ultrasound (US)-mediated technologies show remarkable promise in overcoming these challenges. Absorption of US waves by the tissue results in the generation of heat due to its thermal effect causing increased diffusion of drugs from the carriers and triggering sonoporation by increasing the permeability of the cancer cells. Certain frequencies of US waves could also produce a cavitation effect on drug-filled microbubbles (MBs, phospholipid bilayers) thereby generating shear force and acoustic streaming that could assist drug release from the MBs, and promote the permeability of the cell membrane. A new class of nanoparticles that carry therapeutic agents and are guided by US contrast agents for precision delivery to the site of the ovarian tumor has been developed. Phase-shifting of nanoparticles by US sonication has also been engineered to enhance the drug delivery to the ovarian tumor site. These technologies have been used for targeting the ovarian cancer stem cells and protein moieties that are particularly elevated in OCs including luteinizing hormone-releasing hormone, folic acid receptor, and vascular endothelial growth factor. When compared to healthy ovarian tissue, the homeostatic parameters at the tissue microenvironment including pH, oxygen levels, and glucose metabolism differ significantly in ovarian tumors. US-based technologies have been developed to take advantage of these tumor-specific alterations for precision drug delivery. Preclinical efficacy of US-based targeting of currently used clinical chemotherapies presented in this review has the potential for rapid human translation, especially for formulations that use all substances that are deemed to be generally safe by the U.S. Food and Drug Administration.

3.
Sci Rep ; 9(1): 12244, 2019 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-31439902

RESUMEN

Miniaturization is one of the important research directions of low frequency high power microwave sources. This paper presents a three-period coaxial slow-wave structure L-band high-power microwave source. Because the coaxial Quasi-TEM mode has no cut-off frequency, the radial size of the device can be reduced. At the same time, in order to reduce the transverse dimension, the coaxial extractor structure is introduced to realize the longitudinal mode selection and improve the conversion efficiency of the device. In simulation, the device obtains the microwave output with the central frequency of 1.53 GHz, the average power of 3.3 GW and the efficiency of 40%. By optimizing the scheme of electron beam collection, the phenomenon of pulse shortening is effectively suppressed. In the experiment, the device obtains the microwave output with the central frequency of 1.52 GHz, the average power of 3 GW, the efficiency of 33% and the pulse width of 40 ns.

4.
World J Pediatr ; 14(1): 13-17, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29411325

RESUMEN

BACKGROUND: Postural orthostatic tachycardia syndrome (POTS) is a form of orthostatic intolerance, and its incidence in children is approximately 6.8% [1]. The pathogenesis of POTS is complex with multiple, overlapping, interacting pathophysiological mechanisms. Although the specific pathogenic mechanism has remained perplexing, with the discovery of various gasotransmitters and biological peptides, the vascular dysfunction has aroused overwhelming attention. DATA SOURCES: On the basis of searching in a wide range of recent original literatures, we reviewed the pathogenesis of vascular dysfunction in children with POTS. RESULTS: The flow-mediated vasodilation of POTS patients was greater than that of healthy controls, and the vasodilator factors were increased in patients with POTS under basal condition or under a standing position, while the vasoconstriction factors were reduced. CONCLUSIONS: Vascular dysfunction, as one of pathogenesis in pediatric POTS patients, affects the occurrence and development of diseases through a variety of factors.


Asunto(s)
Síndrome de Taquicardia Postural Ortostática/sangre , Síndrome de Taquicardia Postural Ortostática/epidemiología , Vasodilatación/fisiología , Biomarcadores/sangre , Niño , China/epidemiología , Femenino , Humanos , Incidencia , Masculino , Síndrome de Taquicardia Postural Ortostática/fisiopatología , Medición de Riesgo
5.
Chin Med J (Engl) ; 131(4): 435-439, 2018 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-29451148

RESUMEN

BACKGROUND: The pathogenesis of postural tachycardia syndrome (POTS) remains unclear. This study aimed to explore the changes and significance of sulfur dioxide (SO2) in patients with POTS. METHODS: The study included 31 children with POTS and 27 healthy children from Peking University First Hospital between December 2013 and October 2015. A detailed medical history, physical examination results, and demographic characteristics were collected. Hemodynamics was recorded and the plasma SO2was determined. RESULTS: The plasma SO2was significantly higher in POTS children compared to healthy children (64.0 ± 20.8 µmol/L vs. 27.2 ± 9.6 µmol/L, respectively, P < 0.05). The symptom scores in POTS were positively correlated with plasma SO2levels (r = 0.398, P < 0.05). In all the study participants, the maximum heart rate (HR) was positively correlated with plasma levels of SO2(r = 0.679, P < 0.01). The change in systolic blood pressure from the supine to upright (ΔSBP) in POTS group was smaller than that in the control group (P < 0.05). The ΔSBP was negatively correlated with baseline plasma SO2levels in all participants (r = -0.28, P < 0.05). In the control group, ΔSBP was positively correlated with the plasma levels of SO2(r = 0.487, P < 0.01). The change in HR from the supine to upright in POTS was obvious compared to that of the control group. The area under curve was 0.967 (95% confidence interval: 0.928-1.000), and the cutoff value of plasma SO2 level >38.17 µmol/L yielded a sensitivity of 90.3% and a specificity of 92.6% for predicting the diagnosis of POTS. CONCLUSIONS: Increased endogenous SO2levels might be involved in the pathogenesis of POTS.


Asunto(s)
Postura , Dióxido de Azufre/sangre , Taquicardia/etiología , Adolescente , Estudios de Casos y Controles , Niño , Femenino , Frecuencia Cardíaca , Humanos , Masculino , Sístole
6.
Zhongguo Zhong Yao Za Zhi ; (24): 2126-2143, 2023.
Artículo en Zh | WPRIM | ID: wpr-981344

RESUMEN

Sanhan Huashi formula(SHF) is the intermediate of a newly approved traditional Chinese medicine(TCM) Sanhan Huashi Granules for the treatment of COVID-19 infection. The chemical composition of SHF is complex since it contains 20 single herbal medicines. In this study, UHPLC-Orbitrap Exploris 240 was used to identify the chemical components in SHF and in rat plasma, lung and feces after oral administration of SHF, and heat map was plotted for characterizing the distribution of the chemical components. Chromatographic separation was conducted on a Waters ACQUITY UPLC BEH C_(18)(2.1 mm×100 mm, 1.7 μm) using 0.1% formic acid(A)-acetonitrile(B) as mobile phases in a gradient elution. Electrospray ionization(ESI) source was used to acquire data in positive and negative mode. By reference to quasi-molecular ions and MS/MS fragment ions and in combination with MS spectra of reference substances and compound information in literature reports, 80 components were identified in SHF, including 14 flavonoids, 13 coumarins, 5 lignans, 12 amino-compounds, 6 terpenes and 30 other compounds; 40 chemical components were identified in rat plasma, 27 in lung and 56 in feces. Component identification and characterization of SHF in vitro and in vivo lay foundations for disclosure of its pharmacodynamic substances and elucidation of the scientific connotation.


Asunto(s)
Ratas , Animales , Espectrometría de Masas en Tándem , Cromatografía Líquida de Alta Presión/métodos , Medicamentos Herbarios Chinos/química , COVID-19 , Lignanos
7.
Zhongguo Zhong Yao Za Zhi ; (24): 6066-6074, 2023.
Artículo en Zh | WPRIM | ID: wpr-1008805

RESUMEN

This study comprehensively analyzed the active components of Sanhan Huashi Formula using qualitative and quantitative mass spectrometry techniques, laying the foundation for understanding its pharmacological substance basis. UHPLC-LTQ-Orbitrap-MS and GC-MS technologies were used to analyze and identify the volatile and non-volatile components in Sanhan Huashi Formula. UHPLC-QQQ-MS/MS technology was used to simultaneously determine the content of 27 major active components in the formula. The results showed that 308 major chemical components were identified in Sanhan Huashi Formula, among which 60 compounds were identified by comparing with reference standards, mainly including alkaloids, flavonoids, coumarins, triterpenoid saponins, amino acids, and nucleosides. GC-MS technology preliminarily identified 52 volatile compounds, with γ-eudesmol and β-eudesmol as the main components. The quantitative results demonstrated good linearity(r>0.99) for the 27 active components, indicating the stability, simplicity, and reliability of the established method. Among them, amygdalin, nodakenin, arecoline, ephedrine, and pseudoephedrine had relatively high content and were presumably the main pharmacologically active substances. In conclusion, this study systematically and comprehensively characterized the major chemical components and patterns in Sanhan Huashi Formula, providing a basis for understanding its pharmacological mechanisms and clinical applications.


Asunto(s)
Espectrometría de Masas en Tándem , Cromatografía Líquida de Alta Presión , Cromatografía de Gases y Espectrometría de Masas , Reproducibilidad de los Resultados , Medicamentos Herbarios Chinos/química
8.
World J Gastroenterol ; 9(5): 1106-10, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12717867

RESUMEN

AIM: To determine the prevalence of nonalcoholic fatty liver in a specific population in Shanghai by an epidemiological survey, and to analyze risk factors of fatty liver. METHODS: Total 4009 administrative officers who denied regular alcohol drinking participated in the survey, and underwent physical examination and laboratory tests. The important parameters were body mass index (BMI), waist hip circumferences ratio (WHR) and levels of serum lipids. Diagnosis of fatty liver was based on established real-time ultrasonographic criteria, the presence of an ultrasonographic pattern consistent with "bright liver", with evident ultrasonographic contrast between hepatic and renal parenchyma, vessel blurring, and narrowing of the lumen of the hepatic veins. Analysis of data was performed through SPSS for Windows statistical package. RESULTS: The overall prevalence of fatty liver was 12.9 %, 15.8 % in males and 7.5 % in females, and the prevalence of fatty liver in males younger than 50 years old, was significantly higher (13.3 %) than that of in females (2.7 %). But the difference between the sexes became less significant in people older than 50 years (19.1 % vs 18.1 %). The prevalence of fatty liver was increased with age; this was markedly presented in females younger than 50 years. Multiple variant regression analysis demonstrated that the prevalence of fatty liver was positively correlated to several risk factors, including male, aging (>50yr), hyperlipidemia, impaired glucose tolerance/diabetes mellitus, hypertension and overweight/obesity. CONCLUSION: There is a high prevalence of nonalcoholic fatty liver among certain population in Shanghai, to which overweight and hyperlipidemia are closely relevant.


Asunto(s)
Hígado Graso/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Alanina Transaminasa/sangre , Glucemia/metabolismo , Constitución Corporal , Índice de Masa Corporal , China/epidemiología , Colelitiasis/complicaciones , Estudios Epidemiológicos , Hígado Graso/etiología , Femenino , Antígenos de Superficie de la Hepatitis B/sangre , Humanos , Lípidos/sangre , Masculino , Persona de Mediana Edad , Análisis Multivariante , Factores de Riesgo
9.
Zhonghua Er Ke Za Zhi ; 49(12): 890-4, 2011 Dec.
Artículo en Zh | MEDLINE | ID: mdl-22336353

RESUMEN

OBJECTIVE: To explore the impact of sulfur dioxide (SO(2)) on hydrogen sulfide (H(2)S)/cystathionine-γ-lyase (CSE) and H(2)S/mercaptopyruvate sulfurtransferase (MPST) pathways in the pathogenesis of hypoxic pulmonary hypertension. METHODS: Thirty-two male Wistar rats were randomly divided into four groups: control group (n = 8), hypoxic group (n = 8), hypoxic + SO(2) group (n = 8) and hypoxic + hydroxamate (HDX) group (n = 8). After 21 days of experiment, the concentration and production of H(2)S in lung tissues were measured respectively for each rat. The protein expression of CSE and MPST in intima and media of small pulmonary arteries in rats was detected with immunohistochemical method. RESULTS: Compared with control group, the mean pulmonary artery pressure (mPAP) in rats of hypoxic group was increased significantly [(33.38 ± 6.32) mm Hg vs. (16.74 ± 3.81) mm Hg, P < 0.01]. Compared with hypoxic group, the mPAP in rats of hypoxic + SO(2) group was decreased significantly [(29.65 ± 2.53) mm Hg vs. (33.38 ± 6.32) mm Hg, P < 0.01]. However, compared with hypoxic group, the mPAP in rats of hypoxic + HDX group was increased significantly [(39.44 ± 6.26) mm Hg vs. (33.38 ± 6.32) mm Hg, P < 0.01]. Compared with control group, the concentration [(2.02 ± 0.43) µmol/g vs. (3.11 ± 0.42) µmol/g, P < 0.01] and production [(19.64 ± 3.48) nmol/(g·min)vs. (28.20 ± 5.95) nmol/(g·min), P < 0.05] of H(2)S were decreased significantly in rats of hypoxic group, respectively. When treated with SO(2), hypoxic rats showed an increased concentration [(2.73 ± 0.20) µmol/g vs. (2.02 ± 0.43) µmol/g, P < 0.01] and production [(26.24 ± 1.92) nmol/(g·min) vs. (19.64 ± 3.48) nmol/(g·min), P < 0.01] of H(2)S in lung tissue compared with those without receiving SO(2) treatment. When treated with HDX, hypoxic rats showed a significant decrease in concentration [(1.64 ± 0.23) µmol/g vs. (2.02 ± 0.43) µmol/g, P < 0.05] and production [(13.94 ± 3.63) nmol/(g·min) vs. (19.64 ± 3.48) nmol/(g·min), P < 0.05] of H(2)S in lung tissue compared with those without receiving HDX treatment. As for the expression of CSE in small pulmonary arteries (SPAs), compared with control group, the expression of CSE in intima [(0.31 ± 0.02) vs. (0.36 ± 0.01), P < 0.01] and media [(0.27 ± 0.01) vs. (0.30 ± 0.01), P < 0.01] in rats of hypoxic group was decreased significantly. While compared with hypoxic group, the expression of CSE in intima [(0.35 ± 0.02) vs. (0.31 ± 0.02), P < 0.01] in SPAs of hypoxic + SO(2) group was increased significantly. With HDX treatment, the expression of CSE in intima [(0.26 ± 0.01) vs. (0.31 ± 0.02), P < 0.01] in SPAs of hypoxic group was lower than that without HDX treatment. As for the expression of MPST in SPAs, compared with hypoxic group, the expression of MPST in media [(0.32 ± 0.02) vs. (0.29 ± 0.01), P < 0.01] in SPAs of hypoxic + SO(2) group was increased significantly. CONCLUSION: SO(2) might upregulate H(2)S/CSE and H(2)S/MPST pathways in pulmonary arteries of hypoxic rats.


Asunto(s)
Cistationina gamma-Liasa/metabolismo , Sulfuro de Hidrógeno/metabolismo , Hipertensión Pulmonar/enzimología , Dióxido de Azufre/farmacología , Sulfurtransferasas/metabolismo , Animales , Hipertensión Pulmonar/fisiopatología , Hipoxia/metabolismo , Hipoxia/fisiopatología , Masculino , Arteria Pulmonar/metabolismo , Arteria Pulmonar/fisiopatología , Ratas , Ratas Wistar
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