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991.
Bv8, the amphibian homologue of the mammalian prokineticins, induces a proinflammatory phenotype of mouse macrophages 总被引:3,自引:0,他引:3
Martucci C Franchi S Giannini E Tian H Melchiorri P Negri L Sacerdote P 《British journal of pharmacology》2006,147(2):225-234
1.--The small protein Bv8, isolated from the amphibian skin, belongs to a novel family of secreted proteins linked to several biological effects. We describe the expression of Bv8/prokineticins and their receptors in mouse macrophages, and characterize their proinflammatory activities. 2.--The rodent analogue of Bv8, prokineticin-2, is expressed by macrophages, as well as its G-protein-coupled receptor prokineticin receptor (PKR-1 and PKR-2). PKR-1 is expressed more abundantly. 3.-- Bv8 induces potent chemotaxis of macrophages at concentrations as low as 10(-12) M. 4.-- It stimulates lipopolysaccharide-induced production of the proinflammatory cytokines IL-1 and IL-12, reducing that of the anti-inflammatory cytokine IL-10. The effects are observed starting at the very low concentration of 10(-11) M. 5.--Effects on chemotaxis and cytokine are not pertussis-toxin sensitive, but are completely prevented by addition of the phospholipase inhibitor U73122, suggesting a G(q) protein is involved in the Bv8-induced effects. 6.--Studies in PKR-1 knockout mice indicate that all the activities exerted by Bv8 on macrophages are mediated by the PKR-1 receptor. 7.--In conclusion, Bv8 appears to be able to induce the macrophage to migrate and to acquire a proinflammatory phenotype. 相似文献
992.
Giannini EG Mansi C Dulbecco P Savarino V 《Nutrition (Burbank, Los Angeles County, Calif.)》2006,22(3):334-342
Irritable bowel syndrome (IBS) is the world's most common gastrointestinal functional disorder and is associated with several social and economic costs. Health-related quality of life is often impaired in patients with IBS. The pathophysiologic mechanisms underlying IBS remain poorly defined. The therapeutic approach to patients with IBS is based on symptoms, and fibers may play an important role in treatment. Among the various types of fiber, water-soluble, non-gelling fibers seem to be a promising option for treatment of IBS. Partially hydrolyzed guar gum (PHGG) is a water-soluble, non-gelling fiber that has provided therapeutic benefits. In clinical trials, PHGG decreased symptoms in constipation-predominant and diarrhea-predominant forms of IBS and decreased abdominal pain. Further, an improvement in quality of life was observed in patients with IBS during and after treatment with PHGG. Moreover, PHGG seems to have prebiotic properties because it increases the colonic contents of short-chain fatty acids, Lactobacilli, and Bifidobacteria. 相似文献
993.
Di Pietro N Placanica G Fiorini I Manera C Orlando C Palombo F Saccomanni G Salotti V Macchia M 《Journal of analytical toxicology》2006,30(9):679-682
The purpose of this study was to identify and quantify morphine, codeine, methadone, and 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine using capillary electrophoresis in urine specimens. Adequate peak separation was achieved using nearly neutral pH phosphate buffer and poly(ethylene oxide) as the coating agent. This dynamic coating of the inner surface of the capillary was obtained by rinsing with a solution containing this compound. The electroosmotic flow and the interactions between analytes and the capillary wall surface were reduced, while resolution and reproducibility were thus improved. Detection limits were appropriate for usual analytical requirements in forensic laboratories. 相似文献
994.
995.
Fifty control subjects and 100 patients with damage restricted to one hemisphere were given two memory tests, one requiring immediate recognition of increasingly longer sequences of pictures and the second learning to criterion the order of presentation of eight pictures.On the short-term memory test, left- but not right-brain-damaged patients scored significantly lower than controls. Their inferiority disappeared when the means were corrected for Token Test scores. On the learning test, right-brain-damaged patients performed more poorly than controls and failed to reach criterion in a significantly higher proportion than left-brain-damaged patients. When the standardized scores on the two tests were compared, the left hemisphere group was found to perform more poorly on the short-term than on the long-term memory test, while the right-brain-damaged group showed the opposite pattern. It was concluded that the aid provided by the verbal code in sequential memory for pictures is limited to conditions requiring brief storage, while long-lasting acquisition of a pictorial sequence is mainly mediated by visual images. 相似文献
996.
We explored the potential of a proteoliposome (PL) from the outer membrane of N. meningitidis B, as an immunopotentiator and as a vector for antigen delivery to dendritic cells (DC). DC were incubated with PL resulting in up-regulation of MHC-II, CD40, CD80, and CD86 expression and production of TNFalpha and IL12(p70). Ovoalbumin (OVA) was incorporated within PL (PL-OVA). PL-OVA presented OVA-specific peptides to CD4+ and CD8+ OVA-specific T-cell hybridomas. PL exerts an immunomodulatory effect on DC and is a general system to deliver antigens for presentation to CD4+ and CD8+ T-cells possibly implicated in the induction CD8+ cytotoxic T lymphocytes (CTLs) responses. 相似文献
997.
Bv8 is a small protein secreted by frog skin. Mammalian homologues of Bv8, the prokineticins PK1 and PK2, and their G-protein coupled receptors PKR1 and PKR2 have been identified and linked to several biological effects. Bv8 elicits a dose-dependent reduction in nociceptive threshold to thermal and mechanical stimuli applied to the skin of tail and paw of rats and mice and increases the sensitivity to nociceptive mediators as capsaicin and prostaglandins. The receptors for Bv8/PKs are present in a fraction of peptidergic population of C-fibre neurons, and in a fraction of A myelinated-fibre neurons. In mouse and rat dorsal root ganglia, PKR-expressing neurons also express TRPV1 and the activation of PKRs sensitises TPRV1 to the action of capsaicin. Mice lacking PKR1 gene exhibit impaired Bv8-induced hyperalgesia, develop deficient responses to noxious heat, capsaicin and protons and show reduced thermal and mechanical hypersensitivity to paw inflammation, indicating a requirement for PKR1 signalling associated with activation and sensitisation of primary afferent fibres. PKs are highly expressed by neutrophils and other inflammatory cells and must be considered as new pronociceptive mediators in inflammatory tissues. Bv8-like hyperalgesic activity was demonstrated in extracts of rat inflammatory granulocytes. Bv8 stimulate macrophage and T lymphocyte to differentiate between an inflammatory and Th1 profile indicating that Bv8/PK proteins play a role in immuno-inflammatory responses. Blockade of PKRs may represent a novel therapeutic strategy in acute and inflammatory pain conditions. 相似文献
998.
Could a high resectability rate improve the long‐term survival of patients with proximal bile duct cancer? 总被引:3,自引:0,他引:3
Veroux M Madia C Fiamingo P Caglià P Valastro M Amodeo C Veroux P Gagliano M Basso S D'Amico DF 《Journal of surgical oncology》2006,93(3):199-205
BACKGROUND AND OBJECTIVES: This retrospective study was undertaken to evaluate if high resectability rate could improve the long-term outcome of patients with proximal bile duct cancer. METHODS: Between 1985 and 2001, 50 patients (34 male and 16 female) with proximal bile duct cancer were treated. Thirty-six patients (72%) were considered suitable for surgery, while 14 underwent nonsurgical palliative procedures. Twenty patients had bile duct resection only. Ten patients had Roux-en-Y cholangiojejunostomy with two or three divided segmental hepatic ducts; in 10 patients, the cholangiojejunostomy was performed with four or five divided segmental hepatic ducts. Three patients were treated by palliative transtumoral intubation with Kehr tube. Thirteen patients had bile duct resection plus hepatectomy. Despite the curative intention of the operation, only in 19 (52.7%) patients did the histopathological examination reveal tumor-free margins. RESULTS: There was no operative mortality. Postoperative morbidity was 25%. Overall 1-, 3-, and 5-year survival of the entire surgical group was 61%, 22.5%, and 9%, respectively. In the 19 patients treated with curative intent the survival at 1, 3, and 5 years was 63.1%, 31.5%, and 15.8%, respectively, while in the group that had palliative treatment it was 45%, 15%, and 0%, respectively. CONCLUSIONS: Only margins free from tumor can guarantee an improvement in long-term outcome. Increasing resectability improves survival and could offer a chance of better long-term survival. 相似文献
999.
Pellegatta S Poliani PL Corno D Menghi F Ghielmetti F Suarez-Merino B Caldera V Nava S Ravanini M Facchetti F Bruzzone MG Finocchiaro G 《Cancer research》2006,66(21):10247-10252
Cancer stem-like cells (CSC) could be a novel target for cancer therapy, including dendritic cell (DC) immunotherapy. To address this, we developed experiments aimed at DC targeting of neurospheres (NS) from GL261 glioma cells because neurospheres can be enriched in CSC. We obtained murine neurospheres by growing GL261 cells in epidermal growth factor/basic fibroblast growth factor without serum. GL261-NS recapitulated important features of glioblastoma CSC and expressed higher levels of radial glia stem cell markers than GL261 cells growing under standard conditions (GL261 adherent cells, GL261-AC), as assessed by DNA microarray and real-time PCR. GL261-NS brain gliomas were highly infiltrating and more rapidly lethal than GL261-AC, as evidenced by survival analysis (P < 0.0001), magnetic resonance imaging and histology. DC from the bone marrow of syngeneic mice were then used for immunotherapy of GL261-NS and GL261-AC tumors. Strikingly, DC loaded with GL261-NS (DC-NS) cured 80% and 60% of GL261-AC and GL261-NS tumors, respectively (P < 0.0001), whereas DC-AC cured only 50% of GL261-AC tumors (P = 0.0022) and none of the GL261-NS tumors. GL261-NS expressed higher levels of MHC and costimulatory molecules (CD80 and CD86) than GL261-AC; the JAM assay indicated that DC-NS splenocytes had higher lytic activity than DC-AC splenocytes on both GL261-NS and GL261-AC, and immunohistochemistry showed that DC-NS vaccination was associated with robust tumor infiltration by CD8+ and CD4+ T lymphocytes. These findings suggest that DC targeting of CSC provides a higher level of protection against GL261 gliomas, a finding with potential implications for the design of clinical trials based on DC vaccination. 相似文献
1000.
Michele Stasi Fernando Munoz Claudio Fiorino Massimo Pasquino Barbara Baiotto Piergiorgio Marini Giuseppe Malinverni Riccardo Valdagni Pietro Gabriele 《Radiotherapy and oncology》2006,80(3):363-370
PURPOSE: To investigate the impact of rectum motion on dose - volume histograms of the rectum including filling and of the wall (DVH and DWH, respectively), during 3D-conformal radiotherapy (3DCRT) for localized prostate cancer. MATERIALS AND METHODS: Ten patients received a planning CT scan (CT(0)) and 11-14 CT during 3DCRT for prostate cancer (total CT scans=126). CT images were 3D matched using bony anatomy. A single observer drew the external contours of rectum and rectum wall and the CTV (prostate + seminal vesicles) on CT(0). Patients were asked to empty their rectum before every CT, as generally performed at the Institute for Cancer Research and Treatment (IRCC) before treatment delivery. Bladder was kept full by drinking 500 cm(3) of water 60 min before the scan, according to our protocol. A 4-field box 3DCRT technique was planned and dose statistics/dose - volume histograms of the rectum were calculated for each contour referred to CT(0),CT(1),...,CT(n) for each patient. Average DVHs during treatment were calculated along with their standard deviation (SD(rand)) and compared to the planned DVH. The analyses on the patient population included the assessment of systematic deviation (average difference and SD, named SD(sys)) as well as the average SD(rand) value expressing the random component of organ motion. Rectum shifts were also assessed by anterior and lateral BEV projections. RESULTS: As to the rectum, 8/10 patients showed a "better" average DVH than DVH on CT(0). Wilcoxon test showed a statistically significant reduction when correlating the difference Delta between the average DVH during therapy and planning DVH at CT(0): for instance V(70)Delta = -3.6% and p = 0.022, V(50)Delta = -5.5% and p = 0.022, D(med)Delta = -3.2 Gy and p = 0.007. Average values of DVH systematic difference (average difference between planning scan and treatment), standard deviations (SD(sys)) and average standard deviations of the random fluctuation (SD(random)) were -4.0%, 4.7% and 6.6%, respectively. Whilst the fluctuation results were slightly smaller for DWH. Volume analysis showed a slight systematic variation of the rectal volume between planning and treatment BEV. The average rectal volume during therapy was larger than at the planning CT in 8/10 patients. The systematic shifts of the rectal wall between the planning phase and the treatment were rather small, both below and above the flexure. The larger random fluctuation of the rectum shape was found to be in the cranial half (1 SD=4.4 mm). CONCLUSIONS: The practice of carefully emptying the rectum during simulation and therapy for prostate cancer, which is a safe and simple procedure, reduces the impact of organ motion on dose - volume parameters of the rectum. 相似文献