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991.
Kass R Agha J Bellone S Palmieri M Canè S Bignotti E Henry-Tillman R Hutchins L Cannon MJ Klimberg S Santin AD 《The Journal of surgical research》2003,112(2):189-197
BACKGROUND: Early dissemination of treatment-resistant tumor cells remains the major cause of metastatic recurrence and death in breast cancer patients. Dendritic cells (DCs) are the most powerful antigen-presenting cells, and recently DC-based vaccination has shown great promise for the treatment of human malignancies by immunological intervention. MATERIALS AND METHODS: CD8+ T lymphocytes derived from peripheral blood mononuclear cells stimulated in vitro with autologous breast tumor antigen-pulsed DCs were tested for their ability to induce a HLA class I restricted cytotoxic T lymphocyte (CTL) response against autologous tumor cells. To correlate cytotoxic activity by CTL with T cell phenotype, two-color flow cytometric analysis of surface markers and intracellular cytokine expression was performed. RESULTS: DC pulsed with breast tumor extracts consistently elicited a tumor-specific HLA class I restricted CTL response in vitro in three consecutive patients harboring locally advanced breast cancer. CTL expressed strong cytolytic activity against autologous tumor cells but did not lyse autologous Epstein Barr virus-transformed lymphoblastoid cell lines and showed variable cytotoxicity against the natural killer-sensitive cell line K-562. In all patients, two color flow cytometric analysis of surface markers and intracellular cytokine expression demonstrated that tumor-specific CTL exhibited an heterogeneous CD8+/CD56+ expression and a striking Th1 cytokine bias (IFNgamma(high)/IL-4 (low)). CONCLUSIONS: Tumor lysate-pulsed DCs can consistently stimulate specific CD8+ CTLs able to kill autologous tumor cells in patients with locally advanced breast cancer in vitro. Tumor antigen-pulsed DC-based vaccinations may be appropriate for the treatment of residual and/or chemotherapy-resistant breast cancer refractory to standard salvage treatment modalities. 相似文献
992.
Incidence of cancer after kidney transplant: results from the North Italy transplant program 总被引:5,自引:0,他引:5
Pedotti P Cardillo M Rossini G Arcuri V Boschiero L Caldara R Cannella G Dissegna D Gotti E Marchini F Maresca MC Montagnino G Montanaro D Rigotti P Sandrini S Taioli E Scalamogna M 《Transplantation》2003,76(10):1448-1451
BACKGROUND: Patients undergoing kidney transplantation demonstrate a higher risk of developing cancer as the result of immunosuppressive treatment and concurrent infections. METHODS: The incidence of cancer in a cohort of patients who underwent kidney transplantation between 1990 and 2000, and who survived the acute phase (10 days), was analyzed as part of the North Italy Transplant program. RESULTS: A total of 3,521 patients underwent transplantation during a 10-year period in 10 of 13 participating centers; the length of follow-up after kidney transplant was 67.7+/-36.0 months. During the follow-up, 172 patients developed cancer (39 with Kaposi sarcoma, 38 with lymphoproliferative diseases, and 95 with carcinomas [17 kidney, 11 non-basal cell carcinoma of the skin, 10 colorectal, 8 breast, 7 gastric, 7 lung, 6 bladder, and 3 mesothelioma]). The average time to cancer development after transplant was 40.1+/-33.4 months (range 0-134 months). Twenty-four patients developed cancer within 6 months from the transplant (10 with carcinomas, 7 with Kaposi sarcoma, and 7 with lymphoproliferative diseases). Three patients demonstrated a second primary cancer. The average cancer incidence was 4.9%. The incidence of cancer was 0.01 per year. Independent determinants of cancer development were age, gender, and immunosuppressive protocol including induction. Ten-year mortality was significantly higher in patients with cancer (33.1%) than among patients without cancer (5.3%). The relative risk of death in subjects with cancer was 5.5 (confidence interval 4.1-7.4). CONCLUSIONS: These preliminary data underline the importance of long-term surveillance of transplant recipients, choice of immunosuppressive treatment, and careful donor selection. 相似文献
993.
Ferreira F Filiputti E Arantes VC Stoppiglia LF Araújo EP Delghingaro-Augusto V Latorraca MQ Toyama MH Boschero AC Carneiro EM 《The Journal of nutrition》2003,133(3):695-699
Undernutrition has been shown to affect the autonomic nervous system, leading to permanent alterations in insulin secretion. To understand these interactions better, we investigated the effects of carbamylcholine (CCh) and phorbol 12-myristate 13-acetate (PMA) on insulin secretion in pancreatic islets from rats fed a normal (17%; NP) or low (6%; LP) protein diet for 8 wk. Isolated islets were incubated for 1 h in Krebs-bicarbonate solution containing 8.3 mmol glucose/L, with or without PMA (400 nmol/L) and CCh. Increasing concentrations of CCh (0.1-1000 micro mol/L) dose dependently increased insulin secretion by islets from both groups of rats. However, insulin secretion by islets from rats fed the NP diet was significantly higher than that of rats fed the LP diet, and the dose-response curve to CCh was shifted to the right in islets from rats fed LP with a 50% effective concentration (EC(50)) of 2.15 +/- 0.7 and 4.64 +/- 0.1 micro mol CCh/L in islets of rats fed NP and LP diets, respectively (P < 0.05). PMA-induced insulin secretion was higher in islets of rats fed NP compared with those fed LP. Western blotting revealed that the protein kinase (PK)Calpha and phospholipase (PL)Cbeta(1) contents of islets of rats fed LP were 30% lower than those of islets of rats fed NP (P < 0.05). In addition, PKCalpha mRNA expression was reduced by 50% in islets from rats fed LP. In conclusion, a reduced expression of PKCalpha and PLCbeta(1) may be involved in the decreased insulin secretion by islets from LP rats after stimulation with CCh and PMA. 相似文献
994.
995.
Trypanosoma cruzi poly-zinc finger protein: a novel DNA/RNA-binding CCHC-zinc finger protein 总被引:2,自引:0,他引:2
Espinosa JM Portal D Lobo GS Pereira CA Alonso GD Gómez EB Lan GH Pomar RV Flawiá MM Torres HN 《Molecular and biochemical parasitology》2003,131(1):35-44
A poly-zinc finger protein, designated PZFP1 was identified in Trypanosoma cruzi for the first time. The protein has 191 amino acids, contains seven motifs Cys(X)(2)Cys(X)(4)His(X)(4)Cys. A recombinant PZFP1 was generated in E. coli and the expected 21kDa polypeptide co-purified with two other inducible products of about 42 and 63kDa. Western blot analysis of cell extracts using an anti-PZFP1 antibody recognized a major band of 41kDa. Electrophoretic mobility shift analysis demonstrated that both, recombinant and native PZFP1, specifically interact with single-stranded DNA or RNA oligonucleotides carrying recognition sequences of other CCHC proteins. The protein was localized mainly in the cytoplasm and nucleus as observed by indirect immunofluorescence analysis. PZFP1 interacted specifically with a T. cruzi serine-arginine-rich protein (TcSR) in a yeast two-hybrid assay, suggesting a role in pre-mRNA processing. 相似文献
996.
Ageno W Piantanida E Dentali F Mera V Squizzato A Marchesi C Steidl L Venco A 《Thrombosis research》2003,109(1):31-35
INTRODUCTION: The onset of acute disorders often results in a significant reduction in physical exercise, thus predisposing to further increase in body weight. Weight gain is strongly associated with an increase in metabolic and cardiovascular risk factors. The aim of this study was to assess weight changes occurring after an episode of acute deep venous thrombosis (DVT). MATERIALS AND METHODS: To compare the prevalence of overweight and obesity at baseline and 6 months after acute DVT, and to compare weight changes between patients with DVT treated in hospital or at home over a similar time frame, we evaluated 72 patients (mean age 59.8+/-15.3 years, 34 men and 38 females) with objectively diagnosed DVT. Body mass index (BMI) was recorded at baseline and at 6 months; waist circumference was recorded at 6 months to assess individual patterns of body fat distribution. RESULTS: At baseline, BMI was 27.6+/-4.6 kg/m(2). Overweight and obesity were observed in 33 (45.8%) and 19 (26.4%) patients, respectively. After 6 months, BMI was 28.7+/-5.0 kg/m(2). The prevalence of overweight and obesity was 44.4% and 32%, respectively; visceral pattern of body fat distribution was found in 64.8% of overweight or obese patients. Mean weight gain was 7.12%; inpatients (n=42) showed a higher weight gain than outpatients (n=30) (8.6% and 4.9%, respectively, p=0.046). CONCLUSIONS: We observed a significant weight gain after acute DVT. This weight gain was more marked in hospitalised patients than in outpatients. Our findings suggest that weight control should be considered in all patients with acute DVT. 相似文献
997.
Eleonora Vighi Barbara Ruozi Monica Montanari Renata Battini Eliana Leo 《European journal of pharmaceutics and biopharmaceutics》2007,67(2):320-328
Cationic solid lipid nanoparticles (SLNs) have recently been suggested for non-viral gene delivery as a promising alternative to the liposomes. The aim of this study was to investigate the possibility to obtain re-dispersible cationic SLNs after a freeze-drying process in the absence of lyo- and/or cryoprotectors. The physical-chemical characteristics of cationic SLNs and their ability to bind gene material were investigated before and after the freeze-drying. To perform this study three samples of cationic SLNs, based on stearic acid, Compritol or cetylpalmitate, were prepared and characterized by PCS (photon correlation spectroscopy) and AFM (atomic force microscopy). The results indicated that solely the re-dispersed sample of stearic acid (SLN-SA) became very similar in terms of size and morphology to the fresh prepared sample, although it displayed a sensible reduction of the zeta potential (from 39.2 to 23.3 mV). By both the DSC (differential scanning calorimetry) and the ESCA (electron spectroscopy for chemical analysis) determinations, the reduction of the zeta potential was ascribed to the loss of the cationic lipids from the particle surface due to the rearrangement of the stearic acid lattice after the freeze-drying. Finally, the gel electrophoresis analysis demonstrated that SLN-SA re-suspended in PBS are unable to complex the DNA, while the SLN-SA re-dispersed in water displayed the same ability to bind DNA as the fresh prepared sample. We can conclude that cationic SLNs, based on stearic acid, retain the ability to complex DNA even after the freeze-drying in the absence of lyo- or cryoprotectors; thus, the powder form of this sample represents an attractive candidate to be investigated as in vivo DNA vector formulation. 相似文献
998.
Ferreira F Barbosa HC Stoppiglia LF Delghingaro-Augusto V Pereira EA Boschero AC Carneiro EM 《The Journal of nutrition》2004,134(1):63-67
A low protein diet has been shown to affect the amount and activity of several enzymes and to decrease insulin secretion by islets isolated from rats fed such a diet. To understand the mechanisms involved in this phenomenon, we investigated the effects of forskolin, a stimulator of adenylyl cyclase, on insulin secretion by pancreatic islets from rats fed a normal (17%; NP) or low (6%; LP) protein diet for 8 wk. Isolated islets were incubated for 1 h in Krebs-bicarbonate solution containing 8.3 mmol glucose/L, with or without 10 micromol forskolin/L. The forskolin-induced insulin secretion was higher in islets from NP rats than in those from LP rats (P<0.05). Western blotting revealed that the amount of the alpha catalytic subunit of protein kinase A (PKAalpha) was 35% lower in islets from LP rats than in islets from NP rats (P<0.05). Moreover, PKAalpha mRNA expression was reduced by 30% in islets from LP rats (P<0.05). Our results indicated a possible relationship between a low protein diet and a reduction in PKAalpha expression. These alterations in PKAalpha may be responsible in part for the decreased insulin secretion by islets from rats fed a low protein diet. 相似文献
999.
Vaghetti H Reis D Kerber Nda C Azambuja E Fernandes G 《Revista brasileira de enfermagem》2004,57(3):316-320
A qualitative, exploratory study carried out from March to December 2002 in a university hospital based in the far south of the country, which aimed at identifying the nurses' perception on the administrative actions exercised in their daily work. Thematic categories emerged from data survey and content analysis in the interviews carried out with 10 nurses. We emphasize Category I: Administrative Actions as a Management Instrument; and Category II: Administrative Actions as Direct/indirect Care. In the first one, administrative actions are perceived as planning, coordination, leadership, control, information retention, and organization; the second one depicts administrative actions as an integral part of nursing care. It has been observed that many administrative actions exercised by nurses are inherent to their role, in keeping with the Nurse's Professional Exercise Code, and they are critical for care. 相似文献
1000.
João P Souza Antonio Oliveira-Neto Fernanda Garanhani Surita José G Cecatti Eliana Amaral João L Pinto e Silva 《Reproductive health》2006,3(1):3-4