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21.
Background: Crohn’s disease (CD) is characterized by chronic inflammation of the gastrointestinal tract with alternating periods of exacerbation and remission. The aim of this study was to determine the time-dependent effects of dietary oat beta-glucans on colon apoptosis and autophagy in the CD rat model. Methods: A total of 150 Sprague–Dawley rats were divided into two main groups: healthy control (H) and a TNBS (2,4,6-trinitrobenzosulfonic acid)-induced colitis (C) group, both including subgroups fed with feed without beta-glucans (βG−) or feed supplemented with low- (βGl) or high-molar-mass oat beta-glucans (βGh) for 3, 7, or 21 days. The expression of autophagy (LC3B) and apoptosis (Caspase-3) markers, as well as Toll-like (TLRs) and Dectin-1 receptors, in the colon epithelial cells, was determined using immunohistochemistry and Western blot. Results: The results showed that in rats with colitis, after 3 days of induction of inflammation, the expression of Caspase-3 and LC3B in intestinal epithelial cells did not change, while that of TLR 4 and Dectin-1 decreased. Beta-glucan supplementation caused an increase in the expression of TLR 5 and Dectin-1 with no changes in the expression of Caspase-3 and LC3B. After 7 days, a high expression of Caspase-3 was observed in the colitis-induced animals without any changes in the expression of LC3B and TLRs, and simultaneously, a decrease in Dectin-1 expression was observed. The consumption of feed with βGl or βGh resulted in a decrease in Caspase-3 expression and an increase in TLR 5 expression in the CβGl group, with no change in the expression of LC3B and TLR 4. After 21 days, the expression of Caspase-3 and TLRs was not changed by colitis, while that of LC3B and Dectin-1 was decreased. Feed supplementation with βGh resulted in an increase in the expression of both Caspase-3 and LC3B, while the consumption of feed with βGh and βGl increased Dectin-1 expression. However, regardless of the type of nutritional intervention, the expression of TLRs did not change after 21 days. Conclusions: Dietary intake of βGl and βGh significantly reduced colitis by time-dependent modification of autophagy and apoptosis, with βGI exhibiting a stronger effect on apoptosis and βGh on autophagy. The mechanism of this action may be based on the activation of TLRs and Dectin-1 receptor and depends on the period of exacerbation or remission of CD.  相似文献   
22.
Home parenteral nutrition (HPN) may improve the survival in selected patients with malignant bowel obstruction. This retrospective, medical registry-based study aimed to identify clinical and laboratory markers predicting short survival, which would allow a more accurate selection of patients that would benefit from HPN in inoperative bowel obstruction. In a retrospective analysis of 114 patients receiving HPN, the median survival was 89 days after discharge home, and the three and six-month survival probability was 48% and 26%, respectively. Parenteral nutrition was provided during 98% of overall survival time and ended on a median of one day before the patient’s death. Discontinuing chemotherapy, anemia, severe hypoalbuminemia, and water retention appeared correlated with survival shorter than three months. In these cases, routine initiation of HPN should be discouraged, as it may not bring any benefits to the patient. The decision on the initiation of HPN should be made along with continuing or initiating chemotherapy.  相似文献   
23.
BackgroundArteriovenous fistulae (AVFs) may remain patent after kidney transplantation (KTx), contributing to maladaptive cardiac remodeling. The flow in AVFs is associated with the diameter of its vessels and thus with the AVF location. The main objective of this study is to assess the influence of AVF location and its patency on the self-reported quality of life (QOL) of kidney transplant recipients (KTRs) with past history of hemodialysis.MethodsTo gain clinical data, during a scheduled visit, 353 KTRs were asked to fill out an anonymous questionnaire. From this group, 284 respondents were found eligible for analysis. The outcome was defined as prevalence of symptoms and health status, measured with the Left Ventricular Dysfunction-36 (LVD-36) Questionnaire in symptomatic patients.ResultsThe hemodialysis patients (n = 243) were divided into two groups according to AVF location, i.e., DAVF – distally located AVF – (n = 174) and PAVF – proximally located AVF – (n = 69). The proportion of patients with heart failure (HF) was higher in PAVF group (24% vs. 12%, p = 0.0482). In the multivariable regression, PAVF, serum creatinine levels, and the presence of HF or coronary artery disease (CAD) remained independent predictors of lower functional capacity. Among patients with heart disease, the presence of active AVF was independently associated with worse functional outcome (higher LVD-36 scores).ConclusionsThe influence of persistent PAVF in KTRs seems to be unfavorable, especially when coexisting with CAD or HF. Abbreviations: AVF arteriovenous fistula; BMI body mass index; CAD coronary artery disease; D-AVF distally-located arteriovenous fistula; EC exercise capacity; HD hemodialysis; HF heart failure; KTx kidney transplantation; KTR kidney transplant recipient; LVD-36 Left Ventricle Disfunction – 36; LVEF left ventricle ejection fraction; LVH left ventricle hypertrophy; NYHA New York Heart Association; P-AVF proximally located arteriovenous fistula; PD peritoneal dialysis; PRO patient-reported outcomes; QOL quality of life.  相似文献   
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25.
Adipose tissue yields adult adipose stem cells (ASCs) in large quantities via less-invasive methods. These cells are of interest owing to their modulating properties and paracrine activities, which can be harnessed in regenerative medicine. Many studies on the use of rat fat tissue in an autologous animal model have been conducted; however, the different locations to obtain stromal vascular fraction of rat fat depots have not been fully characterized. The purpose of the current study was to identify optimal source of ASC from various locations of rat body. Animal experiments in vitro revealed that fat depots from cervical fat are an optimal ASC source. A high ASC yield facilitates subsequent studies on autologous transplantation in rats. The secondary objective was to compare the efficiency of osteoinductive media composition and evaluate of osteogenic potential of ASCs for seeding on scaffolds for bone repair. Scaffolds were assessed in vitro, using rat adipose stem cells and three-dimensional (3D) scaffolds comprising polycaprolactone (PCL) or polycaprolactone covered with tricalcium phosphate (PCL + 5%TCP). Seeded ASCs adhere to the surface and migrate to the scaffolds. Upon staining and determining alkaline phosphatase levels, PCL + 5%TCP scaffolds performed better than PCL scaffolds. Furthermore, growth factors such as BMP2 and FGF2 significantly increased ASC mineralization and induced osteogenesis (p?<?0.05). Our results may help select and develop pre-clinical animal model for confirming the use of ASC, alone or in association with appropriate biomaterials for bone repair.  相似文献   
26.
PURPOSE: Recent findings indicating that many genes related to cancer development are silenced by an aberrant DNA methylation suggest that inhibitors of this process may be effective cancer therapeutics. In this study we investigated the efficacy of low-dose 5-aza-2'-deoxycitydine (DAC), a methylation inhibitor, with interleukin (IL) 12, one of the most potent cytokines with antitumor activity. Experimental Design: Mice inoculated with L1210 leukemia cells or with B16F10 melanoma cells were treated with 7 daily injections of low-dose DAC (0.2 mg/kg) and/or 7 daily doses of IL-12 (100 ng/dose). Scid/scid mice as well as monoclonal antibodies against CD4, CD8, and NK1.1 were used to investigate the mechanisms of the antitumor effects of the combination treatment. The activity of murine lymphocytes was measured with enzyme-linked immunospot and (51)Cr release assays. RESULTS: Treatment with DAC or IL-12 given alone produced moderate antitumor effects. In both tumor models combined treatment resulted in potentiated antitumor effects and produced 70% long-term survivors among mice inoculated with L1210 cells. The antitumor efficacy of combined treatment was abrogated in scid/scid mice, and after depletion of CD4(+) and CD8(+) T cells. Mice inoculated with B16F10 melanoma cells had significantly delayed tumor growth after combined treatment with DAC and IL-12. Strong antitumor effect correlated with a significant activation of lymph node-derived CD8(+) and CD4(+) cells. Transient neutropenia was observed in mice under treatment of DAC alone, but remarkably this effect was not potentiated by IL-12. CONCLUSIONS: This study provides the first evidence that antitumor effects of DAC can be strongly potentiated by IL-12 and could be beneficial in an effective low-dose-based antitumor therapy.  相似文献   
27.
PURPOSE: The aim of the present study was to potentiate the antitumor effectiveness of photodynamic therapy (PDT). A cDNA microarray analysis was used to evaluate the gene expression pattern after Photofrin-mediated PDT to find more effective combination treatment with PDT and inhibitor(s) of the identified gene product(s) overexpressed in tumor cells. EXPERIMENTAL DESIGN: Atlas Mouse Stress Array was used to compare the expression profile of control and PDT-treated C-26 cells. The microarray results have been confirmed using Western blotting. Cytostatic/cytotoxic in vitro assay as well as in vivo tumor models were used to investigate the antitumor effectiveness of PDT in combination with cyclooxygenase (COX) 2 inhibitors. RESULTS: PDT induced the expression of 5 of 140 stress-related genes. One of these genes encodes for COX-2, an enzyme important in the tumor progression. Inhibition of COX-2 in vitro with NS-398, rofecoxib, or nimesulide, or before PDT with nimesulide did not influence the therapeutic efficacy of the treatment. Administration of a selective COX-2 inhibitor after PDT produced potentiated antitumor effects leading to complete responses in the majority of treated animals. CONCLUSIONS: COX-2 inhibitors do not sensitize tumor cells to PDT-mediated killing. However, these drugs can be used to potentiate the antitumor effectiveness of this treatment regimen when administered after tumor illumination.  相似文献   
28.
OBJECTIVE: We investigated the effect of pharmacologic (steroids, vasodilators, vitamins, and Betaserc) and hyperbaric oxygen therapy on patients with sudden sensorineural hearing loss. METHODS: The pharmacologic arm of the study consisted of 52 patients with defined sudden sensorineural hearing loss treated simultaneously in the ENT Department and National Center for Hyperbaric Medicine of the Medical University of Gdansk, Poland, from 1997 to 2000 (Group A). The hyperbaric oxygen therapy consisted of exposure to 100% oxygen at a pressure of 250 kPa for a total of 60 minutes in a multiplace hyperbaric chamber. The control group included 81 patients with defined sudden sensorineural hearing loss treated in the ENT Department, Medical University of Gdansk, from 1980 to 1996 (Group B). Both groups were comparable regarding the age of the patients, season of hearing loss occurrence, tinnitus and vestibular symptom frequency, delay before therapy, and average threshold loss before the start of treatment. The treatment results (hearing gain) were estimated using pure-tone audiometry. We retrospectively analyzed the audiograms of all patients. RESULTS: Patients from Group A (blood flow-promoting drugs, glucocorticoids in high doses, betahistine, and hyperbaric oxygen therapy) showed significantly better recovery of hearing levels compared with those from Group B (blood flow-promoting drugs and glucocorticoids in low doses) at seven frequencies (500, 1,000, 2,000, 3,000, 4,000, 6,000, and 8,000 Hz) (p < 0.05) and four groups of frequencies (pure-tone average, high-tone average, pure middle-tone average, and overall average) (p < 0.05). Percentage hearing gain in all investigated frequencies was also better in Group A versus Group B, and the differences were statistically significant (p < 0.05). CONCLUSION: We conclude that hyperbaric oxygen therapy with high doses of glucocorticoids improves the results of conventional sudden sensorineural hearing loss treatment and should be recommended. In addition, the best results are achieved if the treatment is started as early as possible.  相似文献   
29.
The study was aimed at assessing the quality of sexual functioning in female patients having undergone surgical treatment for cancer depending on the type of surgery. The prospective cohort consisted of 48 female patients (23 patients with stoma [A2] and 25 patients with maintained continuity of the GI tract [A1]). Study methods included a diagnostic survey and the analysis of medical records of patients. Research tools consisted of a standardized FSFI questionnaire and a proprietary form for evaluation of sociodemographic data. Measurements were performed at threetimepoints: On the day before the surgery (Measurement I) as well as six and 12 months after the surgery (Measurements II and III, respectively). Statistically significant differences in results were observed in Measurements II and III in the subscales of arousal (II:p = 0.0068, III:p = 0.0018), lubrication (II:p = 0.0221, III:p = 0.0134), orgasm (II:p = 0.0044, III:p = 0.0021), satisfaction (II:p = 0.0021, III:p = 0.0433), and pain/discomfort (II:p = 0.0343, III:p = 0.0473). In all cases, lower scores corresponding to lower quality of sexual functioning were observed in patients in whom stoma had been performed. Statistically significant differences in sexual functioning were observed at Measurements II and III in each group, with the results being significantly (p > 0.05) worse in patients having undergone Hartmann’s procedure or abdominoperineal resection). Variables significantly affecting self-assessed sexual satisfaction included marital status, age, and modality of neoadjuvant treatment. Restoration of the continuity of the gastrointestinal tract is a chance for better self-assessment of the patient’s quality of life as regards sexual functioning.  相似文献   
30.
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