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Aim:

The study was designed to investigate the chemopreventive potential of flavonoidal fractions of Apium leptophyllum fruits (FFALF) on Swiss mice.

Materials and Methods:

Skin tumor or papilloma was developed by topical application of DMBA (25 μg in 0.1 ml acetone) on intrascapular region of mice, twice weekly for 8 weeks. The animals were divided into six groups: Group I (vehicle control); group II (FFALF control, 5 mg/kg); group III (carcinogenic control, DMBA treated initially for 8 weeks); and group IV, V and VI as pre-treated group (FFALF 5, 10 and 20 mg/kg respectively for 16 weeks along with DMBA treatment). After the 16th week of treatment; the tumor morphology, skin histopathology, and biochemical and antioxidant biomarkers were measured and compared with carcinogenic control as well as vehicle control.

Results:

The co-administration of FFALF with DMBA-treated groups showed significant (P ≤ 0.001) prevention against skin papilloma and normalized the status of lipid peroxidation with antioxidant biomarkers in a dose-dependent manner as compared to carcinogenic control.

Conclusions:

Thus, the present study suggests that the FFALF is non-carcinogenic and has chemopreventive potential on DMBA-induced carcinogenesis in mouse, which may be due to the modulation of cutaneous lipid peroxidation or enhancement of total antioxidant capacity.KEY WORDS: Apium leptophyllum, antioxidant biomarker, chemoprevention, DMBA, skin papilloma  相似文献   
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Protein misfolding and fibrillation are the fundamental traits in degenerative diseases like Alzheimer''s, Parkinsonism, and diabetes mellitus. Bioactives such as flavonoids and terpenoids from plant sources are known to express protective effects against an array of diseases including diabetes, Alzheimer''s and obesity. Andrographolide (AG), a labdane diterpenoid is prescribed widely in the Indian and Chinese health care systems for classical efficacy against a number of degenerative diseases. This work presents an in depth study on the effects of AG on protein fibrillating pathophysiology. Thioflavin T fluorescence spectroscopy and DLS results indicated concentration dependent inhibition of human serum albumin (HSA) fibrillation. The results were confirmed by electron microscopy studies. HSA fibril formations were markedly reduced in the presence of AG. Fluorescence studies and UV-Vis experiments confirmed further that AG molecularly interacts with HSA at site. In silico molecular docking studies revealed hydrogen bonding and hydrophobic interactions with HSA in the native state. Thus AG interacts with HSA, stabilizes the native protein structure and inhibits fibrillation. The results demonstrated that the compound possesses anti-amyloidogenic properties and can be promising against some human degenerative diseases.

Andrographolide inhibited HSA protein fibrillation through site specific interactions.  相似文献   
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Fiber Bragg grating (FBG)-based acoustic emission (AE) detection and monitoring is considered as a potential and emerging technology for structural health monitoring (SHM) applications. In this paper, an overview of the FBG-based AE monitoring system is presented, and various technologies and methods used for FBG AE interrogation systems are reviewed and discussed. Various commercial FBG AE sensing systems, SHM applications of FBG AE monitoring, and market potential and recent trends are also discussed.  相似文献   
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Intestinal obstruction promotes gut translocation of bacteria   总被引:11,自引:0,他引:11  
PURPOSE: Translocation of enteric organisms has been implicated as a possible source of sepsis in susceptible patients. Animal studies have suggested that intestinal obstruction promotes bacterial translocation from the gut lumen. The aim of this study was to study the prevalence of bacterial translocation in patients with and without intestinal obstruction. METHODS: Serosal scrapings, mesenteric lymph nodes, and peripheral blood cultures were obtained from 254 patients. Scrapings and nodes were homogenized and incubated aerobically and anaerobically. Full-thickness biopsies underwent villous height analysis. The clinical course was followed for at least six weeks. RESULTS: Bacterial translocation to mesenteric nodes occurred more frequently in patients with large bowel obstruction than in patients without obstruction (14 of 36 patients vs.16 of 218 patients;P<0.001). Both aerobic and anaerobic bacteria were found to translocate. The more distal the obstruction, the more likely anaerobic bacteria were to be identified. Translocation of bacteria predisposed to postoperative septic complications (P<0.05). Villous height was not related to bacterial translocation. CONCLUSIONS: Gut translocation of bacteria is more common in patients with intestinal obstruction, and its association with septic complications appears to be of clinical significance.Supported by the Yorkshire Regional Health Authority Research Trust, Harrogate, United Kingdom.Read at the meeting of The American Society of Colon and Rectal Surgeons, Orlando, Florida, May 8 to 13, 1994.  相似文献   
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