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Abstract

Objective: The strength–duration time constant (SDTC) is a measure of axonal excitability and it can provide information about Na+ channel function. In this study, we sought to examine the changes in the SDTCs of motor and sensory fibers of the median nerve in patients taking colchicine, which affects axoplasmic flow and may result in axonal neuropathy.

Methods and results: The SDTCs of motor and sensory fibers of 29 patients who had been taking colchicine were measured following stimulation of the right median nerve at the wrist. The results were compared with ten healthy age-matched subjects. No significant differences were found between the groups.

Conclusions: The lack of any effect on the SDTC by colchicine might have been due to the fact that axonal degeneration caused by colchicine affects the Na+–K+ ATP pump or that it affects internodal channels other than nodal channels.  相似文献   
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Pancreatic tumors are chemoresistant and malignant, and there are very few therapeutic options for pancreatic cancer, as the disease is normally diagnosed at an advanced stage. Although attempts have been made to develop vaccine therapies for pancreatic cancer for a couple of decades, none of the resultant protocols or regimens have succeeded in improving the clinical outcomes of patients. We herein review vaccines tested within the past few years, including peptide, biological and multiple vaccines, and describe the three sets of criteria used to evaluate the therapeutic activity of vaccines in solid tumors.  相似文献   
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Background

Delayed gastric emptying (DGE) is a common complication of pancreaticoduodenectomy. We determined the efficiency of a new reconstruction technique, designed to preserve motilin-secreting cells and maximize the utility of their receptors, in reducing the incidence of DGE after pancreaticoduodenectomy.

Methods

From April 2005 to September 2014, 217 consecutive patients underwent pancreaticoduodenectomy at our institution. Nine patients who underwent total pancreatectomy were excluded. We compared outcomes between patients who underwent pancreaticoduodenectomy with resection of the pyloric ring followed by proximal Roux-en-y gastrojejunal anastomosis (group I, n?=?90) and patients who underwent standard pancreaticoduodenectomy with the orthotopic reconstruction technique (group II, n?=?118).

Results

Overall and clinically relevant rates of DGE were significantly lower in group I than in group II (10 and 2.2 % vs. 57 and 24 %, respectively; p?<?0.05). Length of hospital stay as a result of DGE was shorter in group I than in group II. In univariate analysis, older age, comorbidities, ASA grade 4, operative time, preoperative diabetes, standard reconstruction technique, and postoperative complications were significant risk factors for DGE. In multivariate analysis, older age, standard technique, and postoperative complications were independent risk factors for DGE.

Conclusion

Our new reconstruction technique reduces the occurrence of DGE after pancreaticoduodenectomy.
  相似文献   
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Purpose

Sepantronium bromide (YM155) is a hydrophilic quaternary compound that cannot be administered orally due to its low oral bioavailability; it is furthermore rapidly eliminated via the kidneys. The current study aims at improving the pharmacokinetic profile of YM155 by its formulation in immunoliposomes that can achieve its enhanced delivery into tumor tissue and facilitate uptake in neuroblastoma cancer cells.

Methods

PEGylated YM155 loaded liposomes composed of DPPC, cholesterol and DSPE-PEG2000 were prepared via passive film-hydration and extrusion method. Targeted (i.e. immuno-)liposomes were prepared by surface functionalization with SATA modified monoclonal anti-disialoganglioside (GD2) antibodies. Liposomes were characterized based on their size, charge, antibody coupling and YM155 encapsulation efficiency, and stability. Flow cytometry analysis and confocal microscopy were performed on IMR32 and KCNR neuroblastoma cell lines. The efficacy of developed formulations were assessed by in-vitro toxicity assays. A pilot pharmacokinetic analysis was performed to assess plasma circulation and tumor accumulation profiles of the developed liposomal formulations.

Results

YM155 loaded immunoliposomes had a size of 170 nm and zeta potential of ?10 mV, with an antibody coupling efficiency of 60% andYM155 encapsulation efficiency of14%. Targeted and control liposomal formulations were found to have similar YM155 release rates in a release medium containing 50% serum. An in-vitro toxicity study on KCNR cells showed less toxicity for immunoliposomes as compared to free YM155. In-vivo pharmacokinetic evaluation of YM155 liposomes showed prolonged blood circulation and significantly increased half-lives of liposomal YM155 in tumor tissue, as compared to a bolus injection of free YM155.

Conclusions

YM155 loaded immunoliposomes were successfully formulated and characterized, and initial in-vivo results show their potential for improving the circulation time and tumor accumulation of YM155.
  相似文献   
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A 13-year-old boy was referred to us for investigation of a giant liver mass, approximately 16 cm in diameter. Sonographically guided percutaneous needle biopsy was performed and histological examination revealed a fetal-type hepatoblastoma. After four courses of chemotherapy, we performed a left hepatic trisegmentectomy. Follow-up computed tomography, 55 months after the surgery, showed a 1-cm tumor on the route of the preoperative needle biopsy. A second laparotomy revealed a peritonealised tumor, which was excised. The histology of this tumor was identical to that of the primary hepatoblastoma. To our knowledge, this is only the second report of needle tract implantation of hepatoblastoma after percutaneous needle biopsy.  相似文献   
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