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Although cooling at ambient temperature is widely used and is said to be safe and convenient, faster cooling may have an influence not only on the time of the manufacturing process but also on the mechanical response, especially the residual stress. The study aimed to investigate the influence of the cooling rate after curing on the mechanical response of filament-wound thick-walled carbon fiber reinforced polymer (CFRP) rings. Three cooling rates were taking into consideration: cooling with the oven, at room temperature, and in the water at 20 °C. The splitting method was used to examine the residual strains. In the radial compression test, the mechanical response was investigated between the rings with different cooling regimes. The FEM analysis of the compression test in elastic range was also performed. Both the splitting method and the radial compression test showed no significant difference in the mechanical response of the CFRP rings. The presented results showed that the fast-cooling rate slightly decreases the mechanical performance of the filament-wound rings.
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INTRODUCTION: Programmed death-1 (PD-1) and programmed death ligand-1 (PD-L1) function as an immune checkpoint pathway that can be exploited by tumor cells to evade immuno-surveillance. The precise role of PD-1/PD-L1 inhibition of the immune response in GC is unknown. The study investigated PD-1 and PD-L1 expression on peripheral T-cells and its potential association with clinicopathological features in gastric cancer (GC) patients. MATERIAL AND METHODS: PD-1/PD-L1 expression on CD4(+) and CD8(+) T-cells from peripheral blood of 40 patients primarily diagnosed with advanced GC was evaluated by multicolor flow cytometry. RESULTS: The frequency of CD4(+)PD-1(+) and CD8(+)PD-1(+) cells in GC patients was higher than in the control group (p < 0.0001 and p < 0.01, respectively). Expression of PD-1 on CD8(+) cells in GC was higher than in the control group (p < 0.0001). The frequency of CD4(+)PD-L1(+) and CD8(+)PD-L1(+) cells was higher than in the control group (p < 0.0001). Expression of PD-L1 on CD4(+) and CD8(+) cells in GC was higher than in the control group (p < 0.0001). A higher frequency of CD4(+)PD-1(+) cells was found in diffuse-type compared to intestinal tumors (p < 0.029). A higher frequency of CD8(+)PD-1(+) cells was found in patients with poorly differentiated compared to well/moderately differentiated tumors (p < 0.019). CONCLUSIONS: Downregulation of peripheral blood CD4(+) and CD8(+) lymphocytes can be associated with PD-1/PD-L1 expression. This can lead to attenuation of the general immune response in GC.
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Gastrectomy induces severe osteoporosis in humans but its quantitative scale within trabecular and cortical compartments was not estimated. The aim of the study was to determine changes of volumetric bone mineral density (vBMD) in lumbar vertebrae (L1-L4) and biochemical bone metabolism markers in serum of patients 1 year after total gastrectomy. The control group consisted of patients (Nâ=â8) subjected to abdominal surgery due to cardiospasmus. Total gastrectomy was performed in the experimental group (Nâ=â6). Volumetric bone mineral density of trabecular and cortical bone of lumbar spine was measured before (baseline) and 1 year after the gastric surgery using the quantitative computed tomography method. Serum concentrations of insulin, insulin-like growth factor-1, tyroxine, interleukin-6, C-terminal telopeptides of type II collagen and bone formation, and resorption markers were determined at baseline and 1 year later, using ELISA, EIA, and IEMA methods. Total gastrectomy induced significant decrease of vBMD values, up to 16.8% and 10.0%, within the trabecular and cortical bone compartments of lumbar spine (Pâ<â0.05). These negative changes of vBMD were associated with significantly increased serum concentration of bone resorption markers such as deoxypyridinoline, pyridinoline, and C-terminal telopeptides of type I collagen, by 13.5%, 32.2%, and 121.5%, respectively (Pâ<â0.05). Neither vBMD nor biochemical bone turnover markers and hormone concentrations were influenced in the control patients. Dramatic bone loss during the first year in gastrectomized patients has proven dynamic osteoporosis progress indicating an importance of treatment interventions in these patients with emphasis on inhibition of intensive bone resorption processes.
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Densidade Óssea , Gastrectomia/efeitos adversos , Vértebras Lombares/patologia , Osteoporose/etiologia , Complicações Pós-Operatórias/etiologia , Biomarcadores/sangue , Estudos de Casos e Controles , Seguimentos , Hormônios/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose/sangue , Osteoporose/patologia , Complicações Pós-Operatórias/sangue , Complicações Pós-Operatórias/patologiaRESUMO
Endoscopic mucosal resection is a minimally invasive technique of resection of large pieces of the superficial layers (the mucosa and partially the submucosa) of the gut wall. In the present study we are presenting currently established indications, recent advances in the technique, early and long-term results of the treatment of esophageal, gastric and colorectal early cancer by endoscopic mucosal resection based on the review of the literature, educational materials and personal experience from the training of the first author (KZ) at the National Cancer Center in Tokyo, Japan. Endoscopic mucosal resection should be indicated for every superficial neoplastic lesion of the gut wall that can be safely removed in its entirety by experienced endoscopic team, and subsequently processed and evaluated properly by cooperating histopathologist specializing in gastrointestinal pathology. Eventually a detailed analysis of a resected specimen enables the precise assessment of curability of the procedure and establishment of the rational management of a patient. Curative endoscopic resection allows for regarding this procedure as sufficient and includes a patient into a follow-up program. Potentially curative endoscopic resection requires to consider the risk of lymph node involvement and discuss with a patient potential benefits and risk associated with surgical treatment or its withholding in reference to patients' age and health condition. Non-curative endoscopic resection requires to recommend an additional local (endoscopic resection, endoscopic ablation, brachytherapy) or surgical treatment after a detailed analysis with a patient a potential benefit and risk associated with each option. Despite enormous advance in medical knowledge the outcome of the gastrointestinal cancer treatment is still far unsatisfactory. Early diagnosis and treatment of less advanced cancer remains the most promising method of improvement of the outcome. We hope that popularization of the knowledge regarding early gastrointestinal cancer may improve their early detection rate and thereby the outcome of the treatment.
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Endoscopia Gastrointestinal/métodos , Mucosa Gástrica/cirurgia , Neoplasias Gastrointestinais/cirurgia , Mucosa Intestinal/cirurgia , Neoplasias do Colo/cirurgia , Neoplasias Esofágicas/cirurgia , Mucosa Gástrica/patologia , Humanos , Mucosa Intestinal/patologia , Neoplasias Gástricas/cirurgia , Resultado do TratamentoRESUMO
Introduction of regional screening programs should be based upon the coherency of epidemiological data and the selection of specific patient groups. This would have significantly reduced costs and improve medical benefits. The aim of the study was to determine the number of patients with colorectal cancer that underwent surgical treatment and achieving clinical and/or pathological data which would be the basis in planning regional screening programs. The data of 1,770 patients that underwent surgical treatment during 1991-2001, in the province of Lublin was attained from the assessment of questionnaires. The results show an increase in morbidity of colorectal cancer in patients over 50 years old in both sexes, irrespectively to primary tumor localization. In 78% of the patients tumors were localized in the distal region of the splenic flexure of colon. The frequency in occurrence of advanced colorectal cancer, morbidity and peri-operative mortality increased due to the patients older age. The results of this research suggest the need to proceed with screening programs in patients over 50 years old with the use of flexible sigmoidoscopy as a method which diagnoses approximately 80% of colorectal cancers.
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Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/patologia , Programas de Rastreamento , Sigmoidoscopia , Idoso , Neoplasias Colorretais/prevenção & controle , Neoplasias Colorretais/cirurgia , Feminino , Humanos , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Polônia/epidemiologia , Sistema de Registros , Inquéritos e QuestionáriosRESUMO
The aim of the study was to determine one-year effects of total gastrectomy on plasma silicon and free amino acid concentrations in patients and evaluate changes of volumetric bone mineral density (vBMD) in lumbar spine. Eight patients were enrolled to the control (CTR) group. Six patients subjected to total gastrectomy (GX group) were included to the experimental group. vBMD in trabecular and cortical bone was measured in lumbar vertebrae at baseline (before surgery) and one year later using quantitative computed tomography. Plasma concentrations of silicon and free amino acids were determined at baseline and one year later using photometric method and ion-exchange chromatography. Body weights within CTR and GX groups were not different after one-year follow-up when compared to the baseline values (P > 0.05). An average annual decrease of vBMD in the trabecular bone in the gastrectomized patients reached 15.0% in lumbar spine and was significantly different in comparison to the percentage changes observed in CTR group (P = 0.02). One-year percentage change of vBMD in the cortical bone in L1 and L2 has shown significantly decreased values by 10.5 and 9.1% in the GX group when compared to the percentage change observed in the controls (P < 0.05). Plasma concentration of adipic acid was significantly higher by 101.6% one year after total gastrectomy procedure in the patients when compared to the baseline value (P = 0.01). Plasma concentration of silicon was significantly lowered by 26.7% one year after the total gastrectomy when compared to the baseline value (P = 0.009). Total gastrectomy in patients has induced severe osteoporotic changes in lumbar spine within one-year period. The observed osteoporotic changes were associated with decreased plasma concentration of silicon indicating importance of exocrine and endocrine functions of stomach for silicon homeostasis maintenance. Gastrectomy-induced bone loss was not related to decreased amino acid concentration in plasma obtained from overnight fasted patients.
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Aminoácidos/sangue , Gastrectomia/efeitos adversos , Silício/sangue , Densidade Óssea , Cromatografia por Troca Iônica , Humanos , Vértebras Lombares/patologia , Masculino , Pessoa de Meia-Idade , FotometriaRESUMO
UNLABELLED: Application of cells with high TAA (tumor associated antigen) presentation potential seems to be crucial in neoplasia immunotherapy. Such feature is distributed in dendritic cells, which present peptides from processed TAA - MHC molecules complex to the T cells of a host. The aim of the study was to assess the influence of colon neoplasia tissue lysate on functioning of generated autologous DC's in the field of autologous CD4+ lymphocytes immunological response towards Th1/Th2 under in vitro environment together with comparison and assessment of DCs' immunosuppressive properties acquired from patients with colon cancer. MATERIAL AND METHODS: The population of this study consisted of 16 healthy- controls, 36colon cancer patients. Blood samples were collected 24h before planned surgery and preventive antibiotic therapy. Neoplastic tissue sample, was digested for cell lysates preparation. DC's generation from PBMC was carried out in standard conditionsand medium enriched with rhGM-CSF and rhIL-4. Mature DC`s and cocultured autologous CD4 lymphocytes immunophenotype assessment was analyzed with flow cytometer. Intracellular and culture medium cytokines concentration was analyzed with ELISA and FACS method. RESULTS: DC`s generated from colon cancer patients stimulated with lysates presented greater maturity, lower expression of CD206 antigen, significantly higher expression of HLA-DR, CD208 and CD209 and high intracellular expression of IL-12, compared to non-stimulated cells. CONCLUSIONS: The neoplastic tissue in vivo produces a number of substances having an unfavorable effect on immune system, our results suggests using lysates as good dendritic cells stimulators that possibly could have application in colon cancer immunotherapy.