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排序方式: 共有1357条查询结果,搜索用时 15 毫秒
61.
Luisa Marracino Angela Punzo Paolo Severi Rosane Nganwouo Tchoutang Celia Vargas-De-la-Cruz Francesca Fortini Francesco Vieceli Dalla Sega Alessia Silla Emanuele Porru Patrizia Simoni Valentina Rosta Alessandro Trentini Achille Wilfred Ouambo Talla Silvana Hrelia Carlo Cervellati Paola Rizzo Cristiana Caliceti 《Nutrients》2022,14(8)
Accumulating evidence suggests that high consumption of natural antioxidants promotes health by reducing oxidative stress and, thus, the risk of developing cardiovascular diseases. Similarly, fermentation of natural compounds with lactic acid bacteria (LAB), such as Lactiplantibacillus plantarum, enhances their beneficial properties as regulators of the immune, digestive, and cardiovascular system. We investigated the effects of fermentation with Lactiplantibacillus plantarum on the antioxidant and immunomodulatory effects of Pushgay berries (Vaccinium floribundum, Ericaceae family) in human umbilical vein endothelial cells (HUVECs) and macrophage cell line RAW264.7. Polyphenol content was assayed by Folin–Ciocalteu and HPLC-MS/MS analysis. The effects of berries solutions on cell viability or proliferation were assessed by WST8 (2-(2-methoxy-4-nitrophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium, monosodium salt and Lactate dehydrogenase (LDH) release, Trypan blue exclusion test, and Alamar blue assay. Antioxidant activity was evaluated by a cell-based chemiluminescent probe for the detection of intracellular H2O2 production in HUVECs. Heme oxygenase-1 (HO-1) expression levels were investigated by RT-qPCR. Glutathione reductase (GR), glutathione peroxidase (Gpx), superoxide dismutase (SOD), and catalase (CAT) activities, as markers of intracellular antioxidant defense, were evaluated by spectrophotometric analysis. The immunomodulatory activity was examined in RAW 264.7 by quantification of inducible nitric oxide synthase (iNOS) and Tumor Necrosis Factor—alpha (TNFα) by RT-qPCR. Data showed that fermentation of Pushgay berries (i) enhances the content of quercetin aglycone, and (ii) increases their intracellular antioxidant activity, as indicated by the reduction in H2O2-induced cell death and the decrease in H2O2-induced HO-1 gene expression in HUVECs treated for 24 h with fermented berries solution (10 µg/mL). Moreover, treatment with Pushgay berries for 72 h (10 µg/mL) promotes cells growth in RAW 264.7, and only fermented Pushgay berries increase the expression of iNOS in the same cell line. Taken together, our results show that LAB fermentation of Pushgay berries enhances their antioxidant and immunomodulatory properties. 相似文献
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Wilfred E. Wooldridge 《Postgraduate medicine》2013,125(3):103-106
The three blistering conditions described in this article—dermatitis herpetiformis, pemphigus vulgaris, and bullous pemphigoid—are unusual but not rare. Proper management is critical and should include supervision by a physician thoroughly familiar with treatment and potential complications. Dr Wooldridge discusses the primary care physician's role in diagnosis, treatment, and follow-up of these diseases. 相似文献
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66.
Yuanmei Lou Genc Basha Robyn P Seipp Bing Cai Susan S Chen Alexander R Moise Andrew P Jeffries Ray S Gopaul Timothy Z Vitalis Wilfred A Jefferies 《Clinical cancer research》2008,14(5):1494-1501
PURPOSE: Tpn is a member of the MHC class I loading complex and functions to bridge the TAP peptide transporter to MHC class I molecules. Metastatic human carcinomas often express low levels of the antigen-processing components Tapasin and TAP and display few functional surface MHC class I molecules. As a result, carcinomas are unrecognizable by effector CTLs. The aim of this study is to examine if Tapasin (Tpn) plays a critical role in the escape of tumors from immunologic recognition. EXPERIMENTAL DESIGN: To test our hypothesis, a nonreplicating adenovirus vector encoding human Tpn (AdhTpn) was constructed to restore Tpn expression in vitro and in vivo in a murine lung carcinoma cell line (CMT.64) that is characterized by down-regulation of surface MHC class I due to deficiency in antigen-processing components. RESULTS: Ex vivo, Tpn expression increased surface MHC class I and restored susceptibility of tumor cells to antigen-specific CTL killing, and AdhTpn infection of dendritic cells also significantly increased cross-presentation and cross-priming. Furthermore, tumor-bearing animals inoculated with AdhTpn demonstrated a significant increase in CD8(+) and CD4(+) T cells and CD11c(+) dendritic cells infiltrating the tumors. Provocatively, whereas syngeneic mice bearing tumors that were inoculated with AdhTpn a significant reduction in tumor growth and increased survival compared with vector controls, combining AdhTpn inoculation with AdhTAP1 resulted in a significant augmentation of protection from tumor-induced death than either component alone. CONCLUSIONS: This is the first demonstration that Tpn alone can enhance survival and immunity against tumors but additionally suggests that Tpn and TAP should be used together as components of immunotherapeutic vaccine protocols to eradicate tumors. 相似文献
67.
L Dashow I Friedman R Kempner J Rudick C McSherry 《Surgery, gynecology & obstetrics》1992,175(1):25-30
Laparoscopic cholecystectomy has changed the treatment of symptomatic gallstones. We present an initial experience with this technique. From March 1990 to March 1991, there were 250 patients who were studied. There were 182 females and 68 males, with most classified as American Society of Anesthesiology Index Class I or II. All procedures were done using electrocautery. There was a definite learning curve for the procedure as evidenced by the duration of the operation. The mean time to perform the procedure was 112 minutes for the first 50 patients and 79 minutes for the last 50 patients. We converted 12 percent of the procedures to an open cholecystectomy for a variety of reasons, the most common being inflammation and adhesions in the triangle of Calot. However, we only had a 4 percent conversion rate in the last 50 patients. There were nine serious complications, with no deaths. The most frequent was a bile leak from the cystic duct stump. Other complications included a pneumothorax, requiring chest tube drainage and an unobserved carcinoma of the stomach. There were no injuries to the common bile duct. The results of our current experience confirm the safety and efficacy of laparoscopic cholecystectomy for the treatment of symptomatic gallstones. The use of electrocautery is safe during laparoscopy and the need for a laser is optional. Laparoscopic cholecystectomy will continue to evolve as more experience is gained and new instruments are introduced. 相似文献
68.
Haroon ZA Amin K Saito W Wilson W Greenberg CS Dewhirst MW 《Cancer biology & therapy》2002,1(2):121-126
Angiogenesis, development of new blood vessels, is essential for wound healing and tumor growth. A potentially important side effect of anti-angiogenic therapy can be delayed wound healing. In this study we address this issue by using a novel in vivo method utilizing fibrin containing dual porous plexiglass chambers (Fibrin Z-Chambers; F-ZC) to investigate wound healing in rats administered with SU5416 (inhibitor of Flk-1 and Flt-1, at 20 mg/kg i.p.). SU5416 treated F-ZCs developed 45% less granulation tissue (p = 0.0076) and showed a 10% reduction in microvessel density (p = 0.0009) than controls treated with drug carrier alone. The granulation tissue showed distinctly decreased collagen deposition (p = 0.0006) in SU5416 treated animals that was associated with 90% reduction in active TGF-beta 1 level. We found that tissue transglutaminase (TG), a cross-linking enzyme involved in TGF-beta 1 activation and matrix stabilization, was inhibited by SU5416. These results suggest that SU5416 delays wound healing by reducing matrix synthesis and stabilization through inhibition of TGF-beta 1 activation. This study was made feasible via the development of a unique method to study anti-angiogenic compounds that provides highly reproducible and quantitative results. Further studies are needed to evaluate in vivo whether anti-angiogenic agents alter wound healing. 相似文献
69.
Executive dysfunction in geriatric depression 总被引:14,自引:0,他引:14
OBJECTIVE: The purpose of this study was to characterize the neuropsychological presentation of geriatric depression and to determine whether depression-related executive dysfunction is more pronounced during advanced age. METHOD: The attention and executive functioning of 40 adults with major depression were compared with those of 40 healthy comparison subjects; 20 subjects were 20-60 years old, and 20 were > or =61 years. It was hypothesized that depressed subjects, regardless of age, would perform more poorly than comparison subjects on both attention and executive tasks but that the older depressed adults would evidence significantly greater impairment on executive measures. RESULTS: A significant interaction between age and depressive status was noted for tasks of executive functioning, while no age-depression interaction was found for tasks of selective or sustained attention. Older depressed adults demonstrated the slowest psychomotor speed and the poorest performance on tasks requiring set shifting, problem solving, and initiation of novel responses. CONCLUSIONS: Patients with late-life depression have significant impairment in executive functioning. These findings can guide the development of stimulated functional neuroimaging paradigms that may clarify the pathophysiology of geriatric depression. Timely identification of attentional and executive processes fundamental to the daily functioning of depressed older adults may lead to compensatory strategies that will improve the outcomes of late-life depression. 相似文献
70.
Percutaneous vertebroplasty for severe osteoporotic vertebral body compression fractures 总被引:30,自引:0,他引:30
PURPOSE: To determine the efficacy of percutaneous vertebroplasty in treating severe vertebral body compression fractures, or vertebra plana, in patients with osteoporosis. MATERIALS AND METHODS: In 155 patients, 310 percutaneous vertebroplasties were performed during 25 months and 15 days. Of these, 37 patients (27 women, 10 men; mean age, 73.6 years) underwent 48 vertebroplasties for severe osteoporotic vertebral body compression fractures. The fractures were defined as vertebrae that have collapsed to less than one-third of their original height. Imaging and clinical features were analyzed, including the extent of vertebral collapse, location of the involved vertebra, pattern of vertebral compression, volume of polymethylmethacrylate injected, vertebroplasty complications, and clinical outcome. RESULTS: Vertebral body collapse averaged 23% (range, 4.5%-33.0%) of the original height. Involved vertebrae were located from levels T5 to L5, with one-half affected at the thoracolumbar junction. Patterns of vertebral compression were divided into gibbus (31 of 48 or 65%), plana (13 of 48 or 27%), and H shape (four of 48 or 8%). The mean volume of the cement injected was 6.0 mL (range, 1.5-12.5 mL). Complications observed on radiographs included cement leakage to the adjacent disc (17 of 48 or 35%) and the paravertebral soft tissues (four of 48 or 8%). There were no major complications. At clinical follow-up (mean duration, 11 months and 3 days; range, 3-24 months), pain relief was complete in 14 (47%) of 30 patients, partial in 15 (50%), and unchanged in one (3%). No patient required surgery. CONCLUSION: Percutaneous vertebroplasty for severe osteoporotic vertebral body compression fractures is safe and effective and should not be withheld in this group of patients. 相似文献