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51.

Background/aims

Pancreatic cancer (PC) is ranked as the fourth leading cause of cancer-related deaths worldwide. Despite recent advances in treatment options, a modest impact on the outcome of the disease is observed so far. Short-term fasting cycles have been shown to potentiate the efficacy of chemotherapy against glioma. The aim of this study was to assess the effect of fasting cycles on the efficacy of gemcitabine, a standard treatment for PC patients, in vitro and in an in vivo pancreatic cancer mouse xenograft model.

Materials and Methods

BxPC-3, MiaPaca-2 and Panc-1 cells were cultured in standard and fasting mimicking culturing condition to evaluate the effects of gemcitabine. Pancreatic cancer xenograft mice were subjected to 24h starvation prior to gemcitabine injection to assess the tumor volume and weight as compared to mice fed ad libitum.

Results

Fasted pancreatic cancer cells showed increased levels of equilibrative nucleoside transporter (hENT1), the transporter of gemcitabine across the cell membrane, and decreased ribonucleotide reductase M1 (RRM1) levels as compared to those cultured in standard medium. Gemcitabine was more effective in inducing cell death on fasted cells as compared to controls. Consistently, xenograft pancreatic cancer mice subjected to fasting cycles prior to gemcitabine injection displayed a decrease of more than 40% in tumor growth.

Conclusion

Fasting cycles enhance gemcitabine effect in vitro and in the in vivo PC xenograft mouse model. These results suggest that restrictive dietary interventions could enhance the efficacy of existing cancer treatments in pancreatic cancer patients.  相似文献   
52.
In October 2001, representatives of 17 European countries (Albania, Bosnia-Herzegovina, Bulgaria, Croatia, Czech Republic, Federal Republic of Yugoslavia, Finland, France, Germany, Greece, Italy, Macedonia, Romania, Slovenia, Spain, Turkey and UK) met in Sarajevo at a course organized by the European School of Transfusion Medicine to discuss their countries' regulations concerning different aspects of the safety of blood transfusion. Results are summarized in tables to facilitate comparisons. Most countries (13/17) have specific transfusion laws and 9/17 have hospital-based systems as opposed to national organizations. Quality assurance is common among investigated countries (14/17). Voluntary associations are responsible for donor promotion in the majority of countries (13/17). Exclusively, voluntary non-remunerated donors are found in 5/17 countries, whereas in the remaining ones, incentives, family replacement and remuneration are mechanisms stimulating blood donation. Medical doctors using official selection criteria are checking donor suitability in virtually all countries, which also perform main microbiological testing. Regulations on good clinical use of blood and derivatives are present in most countries but applied only in some. Although the data presented need to be interpreted with some caution, this preliminary analysis shows that, although some significant differences still exist, the majority of countries studied are moving in the same direction to ensure safety of their blood supply.  相似文献   
53.
Zhou J  Rossi JJ 《Gene therapy》2011,18(12):1134-1138
Highly active antiretroviral therapy (HAART) treatment for HIV has changed the course of AIDS in societies in which the drugs are readily available. Despite the great success of HAART, drug resistance and toxicity issues still remain a concern for some individuals. Thus, a number of investigators have been exploring other approaches for inhibiting HIV-1 replication. One of the most potent of these is the use of RNA interference (RNAi). This review will focus solely on the use of RNAi for the treatment of HIV-1 infection, including the problems, progress and future prospects.  相似文献   
54.
BACKGROUND: Malignant peripheral neuroectodermal tumors (MPNETs) are primitive neuroblastic tumors that arise, unlike neuroblastomas, outside the autonomic nervous system. A renal origin has been described in very few cases. CASE REPORT: We report the case of a young male patient with a large MPNET of the right kidney, studied with ultrasound and computed tomography before surgical resection. The main radiologic features, the microscopic appearance and the typical immunohistochemical findings, are described and discussed.  相似文献   
55.
We aimed to describe body composition changes up to 6–7 months after severe COVID-19 and to evaluate their association with COVID-19 inflammatory burden, described by the integral of the C-reactive protein (CRP) curve. The pectoral muscle area (PMA) and density (PMD), liver-to-spleen (L/S) ratio, and total, visceral, and intermuscular adipose tissue areas (TAT, VAT, and IMAT) were measured at baseline (T0), 2–3 months (T1), and 6–7 months (T2) follow-up CT scans of severe COVID-19 pneumonia survivors. Among the 208 included patients (mean age 65.6 ± 11 years, 31.3% females), decreases in PMA [mean (95%CI) −1.11 (−1.72; −0.51) cm2] and in body fat areas were observed [−3.13 (−10.79; +4.52) cm2 for TAT], larger from T0 to T1 than from T1 to T2. PMD increased only from T1 to T2 [+3.07 (+2.08; +4.06) HU]. Mean decreases were more evident for VAT [−3.55 (−4.94; −2.17) cm2] and steatosis [L/S ratio increase +0.17 (+0.13; +0.20)] than for TAT. In multivariable models adjusted by age, sex, and baseline TAT, increasing the CRP interval was associated with greater PMA reductions, smaller PMD increases, and greater VAT and steatosis decreases, but it was not associated with TAT decreases. In conclusion, muscle loss and fat loss (more apparent in visceral compartments) continue until 6–7 months after COVID-19. The inflammatory burden is associated with skeletal muscle loss and visceral/liver fat loss.  相似文献   
56.
A nosocomial outbreak by cefiderocol (FDC)-resistant NDM-1-producing Klebsiella pneumoniae (NDM-Kp) occurred in a large tertiary care hospital from August 2021–June 2022 in Florence, Italy, an area where NDM-Kp strains have become endemic. Retrospective analysis of NDM-Kp from cases observed in January 2021–June 2022 revealed that 21/52 were FDC-resistant. The outbreak was mostly sustained by clonal expansion of a mutant with inactivated cirA siderophore receptor gene, which exhibited high-level resistance to FDC (MIC ≥ 32 mg/L) and spread independently of FDC exposure.  相似文献   
57.
Neuroendocrine tumors, particularly those of gastrointestinal tract origin, have a predisposition for metastasizing to the liver, causing parenchymal substitution and paraneoplastic syndrome. Lipiodol embolization combined with anticancer drugs is a recent tool in regional therapy. It has been proven that chemoembolization reduces tumor bulk and hormone levels, and that it palliates the symptoms of many patients with liver-dominant neuroendocrine metastases. Beginning in December 1988, ten patients with unresectable and chemotherapy-refractory liver metastatic neuroendocrine tumors were treated with chemoembolization based on a mixture of lipiodol, mitomycin, cisplatin, epirubicin, followed by gelfoam powder and contrast media. Toxicity encountered included: upper right quadrant pain requiring narcotics, elevation of lactate dehydrogenase, alkaline phosphatase, and transaminases. One patient had liver abscess and persistent fever for 2 weeks. We obtained two complete remissions lasting 12 and 34 months and 5 partial remissions. The median survival was 22 months. Four patients had urinary elevation of 5-hydroxyindolacetic acid (5-HIAA). They showed more than a 75% decrease in urinary secretion after treatment. In a patient with transplanted liver we noticed a partial response lasting 7 months. We conclude that chemoembolization will improve the clinical condition of a significant percentage of patients with liver metastases, that future therapy of carcinoid tumors will be based on specific tumor biology and that treatment will be customized for each individual patient combining the use of cytoreductive procedures including radiofrequency ablation, laser treatment and chemoembolization.  相似文献   
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