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51.
Bioavailability of curcumin: problems and promises 总被引:11,自引:0,他引:11
Curcumin, a polyphenolic compound derived from dietary spice turmeric, possesses diverse pharmacologic effects including anti-inflammatory, antioxidant, antiproliferative and antiangiogenic activities. Phase I clinical trials have shown that curcumin is safe even at high doses (12 g/day) in humans but exhibit poor bioavailability. Major reasons contributing to the low plasma and tissue levels of curcumin appear to be due to poor absorption, rapid metabolism, and rapid systemic elimination. To improve the bioavailability of curcumin, numerous approaches have been undertaken. These approaches involve, first, the use of adjuvant like piperine that interferes with glucuronidation; second, the use of liposomal curcumin; third, curcumin nanoparticles; fourth, the use of curcumin phospholipid complex; and fifth, the use of structural analogues of curcumin (e.g., EF-24). The latter has been reported to have a rapid absorption with a peak plasma half-life. Despite the lower bioavailability, therapeutic efficacy of curcumin against various human diseases, including cancer, cardiovascular diseases, diabetes, arthritis, neurological diseases and Crohn's disease, has been documented. Enhanced bioavailability of curcumin in the near future is likely to bring this promising natural product to the forefront of therapeutic agents for treatment of human disease. 相似文献
52.
Varma R Soneja H Samuel N Sangha E Clark TJ Gupta JK 《European journal of obstetrics, gynecology, and reproductive biology》2008,140(1):76-81
BACKGROUND: Thermal balloon endometrial ablation (TBEA) is increasingly being performed in the outpatient setting under local anaesthesia (LA) rather than in a daycase setting under general anaesthesia (GA). Our aim was to compare the post operative rescue analgesia requirements and duration of hospital stay in women undergoing outpatient (LA) and daycase (GA) TBEA. METHODS: Prospective observational study of consecutively recruited women who underwent outpatient (LA) TBEA (n=51) and daycase (GA) TBEA (n=50) over the same time period. Analgesia that was provided additional to the standard administered analgesic regimen was considered rescue analgesia. The main outcome measures were requirement for rescue analgesia and duration of hospital stay in both cohorts. RESULT(S): LA compared to GA cohorts had shorter hospital stays (11h [95% CI 9-13] vs. 17h [95% CI 14-20]) and lower analgesia requirements. However, multivariate regression, correcting for all known confounders, showed that duration of stay was independent of setting for ablation or amount of rescue analgesia. CONCLUSION(S): Duration of hospital stay is not entirely dependent on whether outpatient or daycase endometrial ablation is considered. This unexpected preliminary finding deserves to be validated in future confirmatory trials that compare outpatient and daycase treatments. We also discuss the confounding factors that should be considered when designing such trials. 相似文献
53.
Dudani R Giordano L Sultania P Jha K Florens A Joseph T 《American journal of perinatology》2008,25(4):229-231
Juvenile granulosa cell tumor (JGCT) of testis is extremely rare in childhood. It is considered a benign entity because metastasis has never been reported. Testicular-sparing surgery is the recommended treatment. We reported this case in a newborn who presented with unilateral scrotal swelling. Histopathology and immunohistochemistry confirmed JGCT. Follow-up at 6 months after surgery did not show any recurrence. Even though JGCT is very rare in childhood, it is one of the important differentials of newborn scrotal mass. 相似文献
54.
Alessio Alfieri Juraj Koudelka Mosi Li Sanny Scheffer Jessica Duncombe Andrea Caporali Rajesh N Kalaria Colin Smith Ajay M Shah Karen Horsburgh 《Journal of cerebral blood flow and metabolism》2022,42(7):1176
Chronic microvascular inflammation and oxidative stress are inter-related mechanisms underpinning white matter disease and vascular cognitive impairment (VCI). A proposed mediator is nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 2 (Nox2), a major source of reactive oxygen species (ROS) in the brain. To assess the role of Nox2 in VCI, we studied a tractable model with white matter pathology and cognitive impairment induced by bilateral carotid artery stenosis (BCAS). Mice with genetic deletion of Nox2 (Nox2 KO) were compared to wild-type (WT) following BCAS. Sustained BCAS over 12 weeks in WT mice induced Nox2 expression, indices of microvascular inflammation and oxidative damage, along with white matter pathology culminating in a marked cognitive impairment, which were all protected by Nox2 genetic deletion. Neurovascular coupling was impaired in WT mice post-BCAS and restored in Nox2 KO mice. Increased vascular expression of chemoattractant mediators, cell-adhesion molecules and endothelial activation factors in WT mice post-BCAS were ameliorated by Nox2 deficiency. The clinical relevance was confirmed by increased vascular Nox2 and indices of microvascular inflammation in human post-mortem subjects with cerebral vascular disease. Our results support Nox2 activity as a critical determinant of VCI, whose targeting may be of therapeutic benefit in cerebral vascular disease. 相似文献
55.
Mukul Vij Yogesh Puri Ashwin Rammohan Gowripriya G Rajesh Rajalingam Ilankumaran Kaliamoorthy Mohamed Rela 《World journal of gastrointestinal oncology》2022,14(3):607-627
Cholangiocarcinomas are a heterogeneous group of highly aggressive cancers that may arise anywhere within the biliary tree. There is a wide geographical variation with regards to its incidence, and risk-factor associations which may include liver fluke infection, primary sclerosing cholangitis, and hepatolithiasis amongst others. These tumours are classified into intrahepatic, perihilar and distal based on their anatomical location. Morphologically, intrahepatic cholangiocarcinomas are further sub-classified into small and large duct variants. Perihilar and distal cholangiocarcinomas are usually mucin-producing tubular adenocarcinomas. Cholangiocarcinomas develop through a multistep carcinogenesis and are preceded by dysplastic and in situ lesions. While clinical characteristics and management of these tumours have been extensively elucidated in literature, their ultra-structure and tumour biology remain relatively unknown. This review focuses on the current knowledge of pathological characteristics, molecular alterations of cholangiocarcinoma, and its precursor lesions (including biliary intraepithelial neoplasia, intraductal papillary neoplasms of the bile duct, intraductal tubulopapillary neoplasms and mucinous cystic neoplasm). 相似文献
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59.
Sengottuvel Senthilnathan M.E. Parasakthi Chandrasekaran M.Tech. Mariyappa Narayanan M.Sc. Rajesh Patel B.Tech. Gireesan Katholil Ph.D. Madhukar P. Janawadkar M.Sc. Radhakrishnan S. Thimmakudy Ph.D. Muralidharan R. Thoddi M.D. D.M. 《Annals of noninvasive electrocardiology》2012,17(3):186-194
Background: Extraction of the weak electrical activity of the “His Bundle” (HB) by noninvasive methods has not been very successful in the past. The study reassesses the use of signal averaged magnetocardiography (SAMCG), overcoming some of the limitations in earlier studies including in the signal averaging methodology. Methods: SAMCG on healthy subjects (14 male and 1 female) were performed using R‐peak as the fiducial point in all cases and also using QRS‐onset as the fiducial point in select cases. Results: A conspicuous feature (H) with a magnitude up to 200 femto Tesla (fT) attributed to the HB activity was observed in the PR segment at several spatial positions on the thorax, with onset at 35–50 ms before the QRS‐onset (V) in 15 out of 18 trials constituting 83% of cases studied. The QRS‐onset as the fiducial point resolved the feature better compared to the conventionally used R‐peak, especially in trials exhibiting spread in heart rate (HR). This is attributed to the fluctuations in QonRD (the time interval between QRS‐onset and R‐peak) compared to the temporal stability of the H‐V duration. Conclusions: SAMCG reveals a well‐resolved H feature. The double hump morphology of the feature extended at least up to a frequency of 150 Hz. The importance of the choice of QRS‐onset as the fiducial point is unequivocally demonstrated, illustrated by measurements on subjects exhibiting considerable heart rate variability. The latter has a general validity and should be applicable to SAECG as well. 相似文献
60.