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51.
52.
Melatonin modulates dysregulated circadian clocks in mice with diethylnitrosamine‐induced hepatocellular carcinoma 下载免费PDF全文
Diana I. Sánchez Bárbara González‐Fernández Irene Crespo Beatriz San‐Miguel Marcelino Álvarez Javier González‐Gallego María Jesús Tuñón 《Journal of pineal research》2018,65(3)
Disruption of circadian rhythms, which are regulated by the circadian clock machinery, plays an important role in different long‐term diseases including hepatocellular carcinoma (HCC ). Melatonin has been reported to alleviate promotion and progression of HCC , but the potential contribution of circadian clock modulation is unknown. We investigated the effects of melatonin in mice which received diethylnitrosamine (DEN ) (35 mg/kg body weight ip) once a week for 8 weeks. Melatonin was given at 5 or 10 mg kg?1d?1 ip beginning 4 weeks after the onset of DEN administration and ending at the sacrifice time (10, 20, 30, or 40 weeks). Liver expression of Bmal1, Clock, Npas2, Rorα, and Sirt1 increased, whereas Cry1, Per1, Per2, Per3, CK 1ε, Rev‐erbα, and Rev‐erbβ decreased following DEN administration. Melatonin treatment prevented changes in the expression of clock genes, and this effect was accompanied by an upregulation of the MT 1 receptor and reduced levels of the hypoxia‐inducible factors Hif‐1α and Hif‐2α. An increased expression of p21, p53, and PARP 1/2, a higher Bax/Bcl‐2 ratio, and a lower expression of Cyclin D1, CDK 6, HSP 70, HSP 90, and GRP 78 proteins were also observed in melatonin‐treated mice. Melatonin significantly potentiated the suppression of proliferation and cell cycle arrest induced by the synthetic REV ‐ERB agonist SR 9009 in human Hep3B cells, and BMAL 1 knocking down attenuated the pro‐apoptotic and antiproliferative effect of melatonin. Results support a contribution of changes in the circadian clock components to the beneficial effects of melatonin in HCC and highlight the usefulness of strategies modulating the circadian machinery in hepatocarcinogenesis. 相似文献
53.
ECG‐gated pulmonary artery CTA for evaluation of right ventricular function in patients with acute pulmonary embolism 下载免费PDF全文
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55.
Iñigo Royo Crespo Juan José Rivas de Andrés Raúl Embún Flor Severiano Cortés Franco 《Archivos de bronconeumología》2013
Chondroid chordoma is an extremely rare tumour with an annual incidence of around 0.1 cases per 100,000 population. Involvement of the thoracic vertebrae may be present in 2-5% of cases. 相似文献
56.
The evaluation of gastrointestinal function in diabetic patients 总被引:2,自引:0,他引:2
Quigley EM 《World journal of gastroenterology : WJG》1999,5(4):13-282
Nowadays,anumberofoptionsareavailablefortheasesmentofgastricmotorfunction.Thus,aglobalevaluationofgastricmotorfunctionmaybeob... 相似文献
57.
Crespo S Palacios G Scott S Lago M Puente S Martínez M Baquero M Subirats M 《Annals of hematology》2004,83(5):313-315
Several authors have described a particular potential of automated depolarization analysis in detecting malaria infection as part of the routine full blood count (FBC) performed by the Cell-Dyn 4000 analyzer. In these cases, abnormal depolarizing patterns are due to the presence of leukocyte-associated malaria hemozoin, a pigment which depolarizes the laser light. In this report we describe samples from three individual patients who did not have malaria infection but showed abnormal depolarizing events. Further investigation determined that these samples were from patients infected by the nematode Mansonella perstans. The observed depolarizing pattern consisted of a normal depolarizing eosinophil population and in addition an abnormal depolarizing population that showed a close linear relationship between granularity (90° depolarization) and lobularity (90° polarization). This atypical population was smaller than normal leukocytes and thus clearly different from the patterns associated with malaria infection. Abnormal depolarization patterns of M. perstans clearly do not reflect leukocyte-associated malaria hemozoin. It is possible however that the erythrocyte-lysing agent used to facilitate leukocyte analysis by the instrument may have caused microfilaria fragmentation and thus the distinctive straight-line features of the abnormal scatter plots 相似文献
58.
Cabo RA Castedo E Pastrana M Crespo R Montero CG Ugarte J 《Revista espa?ola de cardiología》2003,56(6):626-628
Pheochromocytoma is a catecholamine-producing tumor and a rare cause of hypertension. Most cases are intra-adrenal and intrapericardial pheochromocytomas are extremely uncommon. We report the case of a 46-year-old woman with a 1-year history of hypertension, in which a right atrial pheochromocytoma was detected after a hypertensive crisis. 131I-metaiodobenzylguanidine scintigraphy and magnetic resonance imaging established the diagnosis. The tumor was successfully resected using cardiopulmonary bypass and the right atrium was reconstructed using bovine pericardium. 相似文献
59.
Effects of Enteral Nutrition on the Barrier Function of the Intestinal Mucosa and Dopamine Receptor Expression in Rats With Traumatic Brain Injury 下载免费PDF全文
Background: Impaired intestinal mucosal barrier (IMB) function is common in traumatic brain injury (TBI), but dopamine receptors (DRs) change in intestinal mucosa after TBI, and effects of enteral nutrition (EN) and supplements on IMB function remain unclear. Our purpose was to study the effects of EN and supplements on intestinal mucosal permeability (IMPB) and the expression of DRs DRD1 and DRD2 in the intestinal mucosa of rats with TBI. Methods: Forty‐eight rats were divided into 8 groups; control, animals with TBI, dopamine group, animals with TBI treated with dopamine antagonist, EN alone, or EN combined with glutamine, probiotics, or a combination of probiotics and glutamine daily after TBI. Results: The IMPB was improved in the glutamine, probiotics, and combination groups. Including probiotics improved IMPB more than adding glutamine, and bacterial translocation in the intestines after TBI was reduced in the probiotics and combination groups (all Ps < .01). TBI led to elevated DRD1 and DRD2 mRNA and protein levels, which were reduced in the DA antagonist, glutamine, probiotics, and combination groups. DRD2 mRNA and protein levels in the probiotics and combination groups were decreased more than in the DA antagonist group (all Ps < .01). The increased IMPB after TBI correlated with increased DRD1 and DRD2 levels in the rat intestinal mucosa. Conclusion: EN supplemented with probiotics or combining glutamine and probiotics lowers the increased IMPB, bacterial translocation, and DRD1 and DRD2 mRNA and protein expression in rat intestinal mucosa caused by TBI. 相似文献
60.
GCH1 attenuates cardiac autonomic nervous remodeling in canines with atrial‐tachypacing via tetrahydrobiopterin pathway regulated by microRNA‐206 下载免费PDF全文