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排序方式: 共有426条查询结果,搜索用时 15 毫秒
51.
52.
Bernhard F. Gibbs Isabel Gon?alves Silva Alexandr Prokhorov Maryam Abooali Inna M. Yasinska Maxwell A. Casely-Hayford Steffen M. Berger Elizaveta Fasler-Kan Vadim V. Sumbayev 《Oncotarget》2015,6(30):28678-28692
Correction of human myeloid cell function is crucial for the prevention of inflammatory and allergic reactions as well as leukaemia progression. Caffeine, a naturally occurring food component, is known to display anti-inflammatory effects which have previously been ascribed largely to its inhibitory actions on phosphodiesterase. However, more recent studies suggest an additional role in affecting the activity of the mammalian target of rapamycin (mTOR), a master regulator of myeloid cell translational pathways, although detailed molecular events underlying its mode of action have not been elucidated. Here, we report the cellular uptake of caffeine, without metabolisation, by healthy and malignant hematopoietic myeloid cells including monocytes, basophils and primary acute myeloid leukaemia mononuclear blasts. Unmodified caffeine downregulated mTOR signalling, which affected glycolysis and the release of pro-inflammatory/pro-angiogenic cytokines as well as other inflammatory mediators. In monocytes, the effects of caffeine were potentiated by its ability to inhibit xanthine oxidase, an enzyme which plays a central role in human purine catabolism by generating uric acid. In basophils, caffeine also increased intracellular cyclic adenosine monophosphate (cAMP) levels which further enhanced its inhibitory action on mTOR. These results demonstrate an important mode of pharmacological action of caffeine with potentially wide-ranging therapeutic impact for treating non-infectious disorders of the human immune system, where it could be applied directly to inflammatory cells. 相似文献
53.
OBJECTIVE: To study the effectiveness and safety of as-needed treatment of formoterol compared with the short-acting alternative terbutaline. METHODS: Two double-blind, 12-month, parallel-group, non-inferiority trials comparing as-needed use of formoterol (Oxis) 4.5 microg and terbutaline (Bricanyl) 0.5 mg via dry-powder inhaler (Turbuhaler), one in 675 patients with intermittent and one in 455 patients with mild persistent asthma, overall 6-87 years of age. Peak expiratory flow (PEF), symptoms, rescue medication use, exacerbations, airway responsiveness (metacholine challenge; subgroup of 127 patients), systemic effects (high single-dose test; subgroup of 87 patients), and safety (adverse events) were assessed. RESULTS: Formoterol 4.5 microg was as effective as terbutaline 0.5 mg with regard to morning PEF (non-inferiority; lower 95% confidence interval limit above -10 L/min). Metacholine sensitivity, exacerbation rates or use of rescue medication did not differ between treatments. Formoterol 54 microg was shown to give less systemic effects than terbutaline 6 mg. Both treatments were safe and well tolerated. CONCLUSIONS: Formoterol 4.5 microg used as needed was at least as effective and safe as terbutaline 0.5 mg used as needed in intermittent and mild persistent asthma, and was associated with less systemic effects when administered as high single doses. 相似文献
54.
Vera Chernonosova Alexandr Gostev Ivan Murashov Boris Chelobanov Andrey Karpenko Pavel Laktionov 《Materials》2021,14(13)
We examined the physicochemical properties and the biocompatibility and hemocompatibility of electrospun 3D matrices produced using polyurethane Pellethane 2363-80A (Pel-80A) blends Pel-80A with gelatin or/and bivalirudin. Two layers of vascular grafts of 1.8 mm in diameter were manufactured and studied for hemocompatibility ex vivo and functioning in the infrarenal position of Wistar rat abdominal aorta in vivo (n = 18). Expanded polytetrafluoroethylene (ePTFE) vascular grafts of similar diameter were implanted as a control (n = 18). Scaffolds produced from Pel-80A with Gel showed high stiffness with a long proportional limit and limited influence of wetting on mechanical characteristics. The electrospun matrices with gelatin have moderate capacity to support cell adhesion and proliferation (~30–47%), whereas vascular grafts with bivalirudin in the inner layer have good hemocompatibility ex vivo. The introduction of bivalirudin into grafts inhibited platelet adhesion and does not lead to a change hemolysis and D-dimers concentration. Study in vivo indicates the advantages of Pel-80A grafts over ePTFE in terms of graft occlusion, calcification level, and blood velocity after 6 months of implantation. The thickness of neointima in Pel-80A–based grafts stabilizes after three months (41.84 ± 20.21 µm) and does not increase until six months, demonstrating potential for long-term functioning without stenosis and as a suitable candidate for subsequent preclinical studies in large animals. 相似文献
55.
56.
M Chvála 《Angewandte Parasitologie》1979,20(1):38-45
The daily activity of Tabanidae (Diptera) was studied in the submountain region of the East Caucasus, district Ismailly, NE Azerbaijan SSR at an altitude 900--1000 m. Tabanidae were collected by the unbaited canopy trap on 8 and 12 July 1976. Females were active from 9 a. m. to 7 p. m., the diurnal biting activity is characterized by a one peak curve with a conspicuous peak of activity between 4 p. m. and 6 p. m. It is suggested that the temperature, relative humidity and the thermic mountain wind are the decisive factors influencing the late afternoon peak of activity. Mating activity of Tabanus unifasciatus at sunrise and of Philipomyia aprica at sunset were observed. 相似文献
57.
Xing M Westra WH Tufano RP Cohen Y Rosenbaum E Rhoden KJ Carson KA Vasko V Larin A Tallini G Tolaney S Holt EH Hui P Umbricht CB Basaria S Ewertz M Tufaro AP Califano JA Ringel MD Zeiger MA Sidransky D Ladenson PW 《The Journal of clinical endocrinology and metabolism》2005,90(12):6373-6379
CONTEXT: Use of BRAF mutation in papillary thyroid cancer (PTC) has the potential to improve risk stratification of this cancer. OBJECTIVE: The objective of the study was to investigate the prognostic value of BRAF mutation in patients with PTC. DESIGN, SETTING, AND SUBJECTS: In a multicenter study of 219 PTC patients, data on their clinicopathological characteristics and clinical courses between 1990 and 2004 were retrospectively collected, and their tumor BRAF mutation status was determined. Associations of BRAF mutation with initial tumor characteristics and subsequent recurrence were analyzed. MAIN OUTCOME MEASURE: Relationships between the BRAF mutation status and clinicopathological outcomes, including recurrence, were measured. RESULTS: We found a significant association between BRAF mutation and extrathyroidal invasion (P < 0.001), lymph node metastasis (P < 0.001), and advanced tumor stage III/IV (P = 0.007) at initial surgery. This association remained significant on multivariate analysis, adjusting for conventional clinicopathological predictors of recurrence excluding the histological PTC subtype, but was lost when the tumor subtype was included in the model. BRAF mutation was also significantly associated with tumor recurrence, 25 vs. 9% with and without mutation, respectively (P = 0.004), during a median of 15 (interquartile range, 3-29) months of follow-up. This association remained significant on multivariate analysis adjusting for conventional clinicopathological predictors of recurrence, even including the PTC subtype (odds ratio, 4.0; 95% confidence interval, 1.1-14.1; P = 0.03). BRAF mutation was even an independent predictor of recurrence in patients with stage I/II disease, 22 vs. 5% with and without BRAF mutation, respectively (P = 0.002). BRAF mutation was also more frequently associated with absence of tumor I-131 avidity and treatment failure of recurrent disease. CONCLUSIONS: In patients with PTC, BRAF mutation is associated with poorer clinicopathological outcomes and independently predicts recurrence. Therefore, BRAF mutation may be a useful molecular marker to assist in risk stratification for patients with PTC. 相似文献
58.
Holothurins B(2), B(3), and B(4), new triterpene glycosides from mediterranean sea cucumbers of the genus holothuria 总被引:2,自引:0,他引:2
Silchenko AS Stonik VA Avilov SA Kalinin VI Kalinovsky AI Zaharenko AM Smirnov AV Mollo E Cimino G 《Journal of natural products》2005,68(4):564-567
Triterpene glycosides of three species of the Mediterranean sea cucumbers Holothuria polii, Holothuria tubulosa, and Holothuria sp. were studied. Three new monosulfated biosides, holothurins B(2) (1), B(3) (2), and B(4) (3), along with the previously known holothurins A (4) and B (5) were isolated from the sea cucumber H. polii. Triterpene glycosides belonging to holothurin A and B groups were found in H. tubulosa, while only one individual glycoside, holothurin A (4), was isolated from Holothuria sp. Structures of new substances were elucidated on the basis of spectral data (2D NMR and MS). The significance of holothurins as chemotaxonomic markers of the animals belonging to the genus Holothuria and taxonomic status of some representatives of the holothurians studied are discussed. 相似文献
59.
4-(2',4'- Difluorobiphenyl-4-yl)-2-methylbutyric acid (deoxoflobufen, VUFB 19053, CAS 847475-35-8) has been developed as a new omega-biphenyl-alkanoic acid and studied in comparison with the racemic form of 4-(2',4'-difluorobiphenyl-4-yl)-2-methyl-4-oxobutanoic acid (flobufen, CAS 112344-52-2). The compounds were tested in a series of models including acute inflammation induced by carrageenan, adjuvant arthritis, in vitro inhibition of the leuktotriene B4 (LTB4) production, reaction of the graft versus the host (GVHR), production of specific antibodies against ovalbumin, peritoneal exudate formation induced by thioglycollate and phagocytosis of thioglycollate-stimulated mouse peritoneal macrophages. Deoxoflobufen exhibited strong anti-inflammatory, antiarthritic and immunomodulatory effects in most of the performed tests. Anti-inflammatory and antiarthritic effects are fully comparable with those of flobufen, however, the compound is less toxic and has apparently stronger immunomodulating effects. 相似文献
60.