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981.
982.
Festa M Capasso A D'Acunto CW Masullo M Rossi AG Pizza C Piacente S 《Journal of natural products》2011,74(12):2505-2513
The effect of the biologically active prenylated chalcone and potential anticancer agent xanthohumol (1) has been investigated on apoptosis of the T98G human malignant glioblastoma cell line. Compound 1 decreased the viability of T98G cells by induction of apoptosis in a time- and concentration-dependent manner. Apoptosis induced by 1 was associated with activation of caspase-3, caspase-9, and PARP cleavage and was mediated by the mitochondrial pathway, as exemplified by mitochondrial depolarization, cytochrome c release, and downregulation of the antiapoptotic Bcl-2 protein. Xanthohumol induced intracellular reactive oxygen species (ROS), an effect that was reduced by pretreatment with the antioxidant N-acetyl-L-cysteine (NAC). Intracellular ROS production appeared essential for the activation of the mitochondrial pathway and induction of apoptosis after exposure to 1. Oxidative stress due to treatment with 1 was associated with MAPK activation, as determined by ERK1/2 and p38 phosphorylation. Phosphorylation of ERK1/2 and p38 was attenuated using NAC to inhibit ROS production. After treatment with 1, ROS provided a specific environment that resulted in MAPK-induced cell death, with this effect reduced by the ERK1/2 specific inhibitor PD98059 and partially inhibited by the p38 inhibitor SB203580. These findings suggest that xanthohumol (1) is a potential chemotherapeutic agent for the treatment of glioblastoma multiforme. 相似文献
983.
Robert A. Baiocchi MD Lapo Alinari MD Mark E. Lustberg MD Thomas S. Lin MD Pierluigi Porcu MD Xiaobai Li Jeffrey S. Johnston John C. Byrd MD Kristie A. Blum MD 《Cancer》2011,117(11):2442-2451
BACKGROUND:
In vitro studies in mantle cell lymphoma (MCL) cell lines and patient‐derived cells have demonstrated synergistic apoptosis with combined rituximab and bortezomib (R‐bortezomib) compared with single‐agent bortezomib. Therefore, the authors of this report evaluated R‐bortezomib in a preclinical model and in a phase 2 clinical trial.METHODS:
A Hu‐MCL‐severe combined immunodeficiency (SCID) model engrafted with the Jeko cell line was treated with R‐bortezomib, bortezomib, or rituximab. Twenty‐five patients with relapsed follicular lymphoma (n = 11) and MCL (n = 14) received 375 mg/m2 rituximab on Days 1 and 8 and 1.3 to 1.5 mg/m2 bortezomib on Days 1, 4, 8, and 11 every 21 days for a median of 3 cycles (range, 1‐5 cycles).RESULTS:
R‐bortezomib resulted in a statistically significant improvement in overall survival in Hu‐MCL‐SCID mice. In the clinical trial, the overall response rate was 40% in all 25 patients, 55% in patients with follicular lymphoma, and 29% in patients with MCL. The estimated 2‐year progression‐free survival (PFS) rate was 24% (95% confidence interval [CI], 10%‐53%) in all patients and 60% (95% CI, 20%‐85%) in responding patients. Thirteen patients (52%) developed grade 3 neurotoxicity, which consisted of constipation/ileus, sensory or motor neuropathy, or orthostatic hypotension. Patients who were heterozygous for the CD32a (Fcγ receptor IIa) 131 histidine (H) to arginine (R) polymorphism had a significantly decreased PFS (P = .009) after R‐bortezomib compared with HH and RR homozygotes.CONCLUSIONS:
R‐bortezomib had significant activity in patients with relapsed or refractory follicular lymphoma and MCL, although an unexpectedly high incidence of grade 3 neurologic toxicity was a potential limiting factor with this combination. Cancer 2011. © 2010 American Cancer Society. 相似文献984.
Tomao F Spinelli G Vici P Pisanelli GC Cascialli G Frati L Panici PB Tomao S 《Expert review of anticancer therapy》2011,11(8):1253-1263
The current adjuvant therapy for breast cancer is in a continous progress; standard therapeutic strategies include the use of chemotherapy, molecular targeted drugs and hormonal agents, according to well-established prognostic and predictive factors. Among the hormonal drugs, for a long period tamoxifen has been the gold standard of adjuvant therapy in postmenopausal women with hormone receptor-positive (HR+) early breast cancer. In the last years an expanding use of aromatase inhibitors occurred in this subset of patients, because the third-generation class of these agents (anastrozole, letrozole and exemestane) showed to be more effective and safe than tamoxifen and are now recommended as the preferred hormonal approach to postmenopausal hormone-sensitive patients, according to national and international guidelines. Treatment choices with these agents include the use of an aromatase inhibitor as an upfront strategy for 5 years, as a sequential approach after 2-3 years of tamoxifen, or as an extended use after the classical 5 years of tamoxifen. The improved efficacy of aromatase inhibitors over tamoxifen has been largely demonstrated in terms of better disease-free survival, reductions in the occurrence of early distant metastasis as well as improvement of overall survival. Moreover, according to the optimal duration of therapy, presently it is not known whether aromatase inhibitor therapy, as tamoxifen, should be limited to 5 years. In terms of safety profile, the side effects of aromatase inhibitors, as compared with selective estrogen receptor modulators, are different, reflecting the specific mechanism of action of these drugs. There is strong evidence that aromatase inhibitors are well tolerated, with a lower incidence of gynecological symptoms (vaginal bleeding, discharge and endometrial neoplasia), venous thromboembolic events and hot flushes than tamoxifen. On the other hand, the use of aromatase inhibitors has been associated with loss of bone density, arthralgia, myalgia, and a negative effect on lipid metabolism and cardiovascular risk. More extensive and mature studies are necessary to well establish the safety of aromatase inhibitors when given to patients with breast cancer for a long time. 相似文献
985.
Daniela Capello Silvia Rasi Pierluigi Oreste Silvio Veronese Michaela Cerri Erika Ravelli Davide Rossi Ernesto Minola Anna Colosimo Marcello Gambacorta Giuliana Muti Enrica Morra Gianluca Gaidano 《The Journal of pathology》2009,218(4):478-486
Post‐transplant lymphoproliferative disorders (PTLDs) represent a frequent complication of solid organ transplantation. Although most PTLDs arise from recipient lymphoid cells, a considerable fraction of cases may arise from donor B‐cells. In an attempt to clarify the histogenesis and pathogenesis of PTLDs derived from donor B‐cells, monoclonal PTLDs occurring in liver transplant recipients were chosen as a model to compare donor (D‐PTLDs) versus recipient PTLDs (R‐PTLDs). The tumour panel included nine D‐PTLDs and six R‐PTLDs. D‐PTLDs were early‐onset, EBV‐infected lymphoproliferations classified as polymorphic PTLD (P‐PTLD; n = 7) or diffuse large B‐cell lymphoma (DLBCL; n = 2) with tumour localization confined to the hepatic hilum. All R‐PTLDs were late‐onset DLBCLs and showed extrahepatic localization. A BCL‐6?/MUM1+/CD138+/? phenotype, consistent with a post‐germinal centre (GC) stage of pre‐terminal B‐cell differentiation, was observed in all D‐PTLDs and in 2/6 R‐PTLDs, whereas a BCL6+/MUM1?/CD138? profile, reminiscent of GC B‐cells, was detected in 4/6 R‐PTLDs. The presence of somatic IGHV hypermutation was observed in 6/9 D‐PTLDs and in 4/6 R‐PTLDs, suggesting derivation from antigen‐experienced B‐cells. IGHV4‐39 was the IGHV gene most frequently encountered, being rearranged in 3/9 D‐PTLDs. Among IGHV‐mutated PTLDs, a mutational profile suggesting antigen stimulation and/or selection was observed in 4/6 D‐s and in 2/4 R‐PTLDs. The presence of ongoing IGHV mutations was detected in 2/4 D‐PTLDs. Aberrant SHM was detected in 10/15 (66.7%) PTLDs, including 6/9 D‐PTLDs and 4/6 R‐PTLDs. Our findings suggest that (i) D‐PTLDs show a clinical presentation distinct from R‐PTLDs; (ii) immunophenotypic and genetic features of D‐PTLDs are consistent with mature, GC‐experienced B‐cells; (iii) transformed donor‐derived B‐cells may experience antigen‐driven stimulation and selection, and may acquire genetic lesions during neoplastic expansion in the recipient environment; and (iv) EBV infection and expression of viral oncoproteins may be relevant in the pathogenesis of D‐PTLDs. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
986.
Capuano A De Corato A Treglia M Tringali G Navarra P 《Pharmacology, biochemistry, and behavior》2011,97(3):544-550
Combination therapy with two drugs is a straightforward strategy to improve the risk-benefit ratio of analgesic treatments. Flupirtine is a non-opioid analgesic drug acting via the enhancement of so-called M currents, associated to Kv7 potassium channels in the central nervous system. In this study we used the orofacial formalin test as a model of acute inflammatory pain in the rat; putative synergistic interactions between flupirtine and morphine or tramadol, given in various combinations, were investigated. We found that flupirtine exerts antinociception in the second phase of the test, whereas morphine and tramadol induced analgesia both in the first and in the second phase. An isobolographic analysis of data was carried out, showing a synergistic interaction between flupirtine and morphine, as well as between flupirtine and tramadol, in the second phase of the test. Conversely, in the first phase of the test only a single combination of morphine plus flupirtine, but not any of the combinations of tramadol and flupirtine, resulted in a synergistic interaction. Our data clearly indicate that flupirtine enhances in a synergistic manner the acute antinociceptive effects exerted by opioids in this paradigm. 相似文献
987.
Antonio Siniscalchi Lucia Aurini Beatrice Benini Lorenzo Gamberini Stefano Nava Pierluigi Viale Stefano Faenza 《World Journal of Transplantation》2016,6(2):389-395
AIM: To determine the incidence, etiology, risk factors and outcome of ventilator-associated pneumonia (VAP) in patients undergoing orthotopic liver transplantation (OLT).
METHODS: This retrospective study considered 242 patients undergoing deceased donor OLT. VAP was diagnosed according to clinical and microbiological criteria.
RESULTS: VAP occurred in 18 (7.4%) patients, with an incidence of 10 per 1000 d of mechanical ventilation (MV). Isolated bacterial etiologic agents were mainly Enterobacteriaceae (79%). Univariate logistic analysis showed that model for end-stage liver disease (MELD) score, pre-operative hospitalization, treatment with terlipressin, Child-Turcotte-Pugh score, days of MV and red cell transfusion were risk factors for VAP. Multivariate analysis, considering significant risk factors in univariate analysis, demonstrated that pneumonia was strongly associated with terlipressin usage, pre-operative hospitalization, days of MV and red cell transfusion. Mortality rate was 22% in the VAP group vs 4% in the group without VAP.
CONCLUSION: Our data suggest that VAP is an important cause of nosocomial infection during postoperative period in OLT patients. MELD score was a significant risk factor in univariate analysis. Multiple transfusions, treatment with terlipressin, preoperative hospitalization rather than called to the hospital while at home and days of MV constitute important risk factors for VAP development. 相似文献
988.
Marcella Pedull& agrave Vincenzo Fierro Pierluigi Marzuillo Ester Del Tufo Anna Grandone Laura Perrone Emanuele Miraglia del Giudice 《World Journal of Clinical Pediatrics》2016,5(3):306-310
AIM: To verify if subclinical hypothyroidism (SCH) could be associated to atopy in children.
METHODS: Seven hundred and thirty-two Caucasian children from South Italy presenting symptoms of allergic disease were enrolled and submitted to atopy, obesity, chronic low grade inflammation, and SCH work up.
RESULTS: Four hundred and forty-five out of 705 (63.12%) children affected by allergic disease were diagnosed as atopic and 260 (36.88%) as not atopic. The SCH prevalence was 6.3%. Significant higher prevalence of SCH among atopic children with average (group 2) and high (group 3) low grade chronic inflammation compared to atopic children with mild (group 1) low grade chronic inflammation was present. Moreover, group 1 and group 2 presented an OR to show SCH of 2.57 (95%CI: 1.55-6.26) and 2.96 (95%CI: 1.01-8.65), respectively. Both in atopic and not atopic children we found C3 serum levels significantly higher in group 3 respect to group 2 and group 1. Noteworthy, among atopic patients, also total immunoglobulin E (IgE) serum levels, were significantly higher in group 3 compared to group 2 and group 1 children. In atopic children, C3 and total IgE serum values increased in parallel with the increase of C-reactive protein values, while in not atopic children this phenomenon was not evident.
CONCLUSION: The possibility exists that an increasing atopic inflammation contributes to SCH occurrence. So far this is the first report in literature showing an association between SCH and atopy but further studies are needed to confirm our data. 相似文献
989.
Marcella Pedull& agrave Vincenzo Fierro Pierluigi Marzuillo Francesco Capuano Emanuele Miraglia del Giudice Eleonora Ruocco 《World Journal of Clinical Pediatrics》2016,5(3):288-292
AIM: To verify the prevalence of thyroid autoimmunity (TA) and the possible association between atopy and TA in children affected by skin disease.
METHODS: Three hundred and twenty-four children consecutively referred due to skin disease symptoms to our Pediatric Department were enrolled. One hundred and eighty-seven were diagnosed with atopic dermatitis (AD), 95 with acute urticaria, 40 with chronic urticaria (CU), and 2 with alopecia areata (AA). According to the work-up for atopy, the children were divided into two groups: Atopics and non-atopics. TA was diagnosed by serum thyroid peroxidase autoantibodies and/or thyroglobulin autoantibodies levels more than twice normal values over a period of two months by immunoassay.
RESULTS: In all children with skin disease, a significant prevalence of TA in atopics compared with non-atopics (13.67% vs 2.67%, P = 0.0016) and a significant association between TA and atopy (OR = 5.76, 95%CI: 1.71-19.35) were observed. These findings were confirmed as significant in children with AD: TA in atopics was 11.5%, while TA in non-atopics was 2.7% (P = 0.03, OR = 4.68, 95%CI: 1.02-21.38). In addition, atopics with CU showed a significantly higher prevalence of TA (26.9%), but none of the non-atopics showed CU (P = 0.0326). On the other hand, atopics with AA showed a 100% (2 out of 2) prevalence of TA, compared with none of the non-atopics.
CONCLUSION: In children with skin disease, atopy seems to be associated with an increased risk of TA. 相似文献