Optimization of hyphenated asymmetric flow field-flow fractionation for the analysis of silver nanoparticles in aqueous solutions.

The extensive use of silver nanoparticles (AgNPs) in consumer products, medicine, and industry leads to their release into the environment. Thus, a characterization of the concentration, size, fate, and toxicity of AgNPs under environmental conditions is required. In this study, we present the characterization and optimization of an asymmetric flow field-flow fractionation (AF4) system coupled with UV/Vis spectrophotometer and dynamic light scattering (DLS) detector as a powerful tool for the size separation and multi-parameter characterization of AgNPs in complex matrices.

Lab-on-chip analyser for the in situ determination of dissolved manganese in seawater.

A spectrophotometric approach for quantification of dissolved manganese (DMn) with 1-(2-pyridylazo)-2-naphthol (PAN) has been adapted for in situ application in coastal and estuarine waters. The analyser uses a submersible microfluidic lab-on-chip device, with low power (~ 1.5 W) and reagent consumption (63 µL per sample).

Fluorescence lifetime-based sensing of sodium by an optode.

We report a 1,2,3-triazol fluoroionophore for detecting Na(+) that shows in vitro enhancement in the Na(+)-induced fluorescence intensity and decay time. The Na(+)-selective molecule 1 was incorporated into a hydrogel as a part of a fiber optical sensor. This sensor allows the direct determination of Na(+) in the range of 1-10 mM by measuring reversible fluorescence decay time changes.

Endothelin(A) receptor blockade reduces ischemia/reperfusion injury in pig pancreas transplantation.

Objective: The effect of prophylactic administration of a selective endothelin(A) receptor antagonist (ET(A)-RA) on ischemia/reperfusion injury in an experimental model of graft pancreatitis after pancreas transplantation was evaluated.

Summary Background Data: It is well established that endothelin-1 (ET-1), a powerful vasoconstrictor, plays an important role in the development of pancreatitis. Recent studies have shown a beneficial effect of endothelin receptor antagonists in the therapy for experimental pancreatitis.

Outcome after duodenum-preserving pancreatic head resection is improved compared with classic Whipple procedure in the treatment of chronic pancreatitis.

Background: There is no consensus in the surgical management of chronic pancreatitis (cP) as to whether techniques preserving the duodenum are superior to pancreatoduodenectomy. This prospective study compared the outcome of standard pancreatoduodenectomy (PD) and duodenum-preserving pancreatic head resection (DPPHR) in treatment of selected patients with cP.

Methods: Inclusion criteria for this prospective controlled, nonrandomized study were patients suffering from cP centered in the head and with severe pain.

Human liver allograft acceptance and the "tolerance assay". II. Donor HLA-A, -B but not DR antigens are able to trigger regulation of DTH.

In our initial study of liver transplant recipients using the trans vivo delayed-type hypersensitivity (DTH) assay, we found that in donor derived B-LCL or sonicates of donor leukocytes triggered linked suppression of the response to recall antigens tetanus toxoid (TT) or Epstein-Barr virus (EBV). Since both donor antigen sources contain HLA class I and class II proteins, we wished to determine which donor HLA proteins were responsible for the linked suppression effect. PBMC from four liver transplant recipients with donor-specific DTH regulation were studied.

Genetic and epigenetic alterations of the INK4a-ARF pathway in cholangiocarcinoma.

The INK4a-ARF locus, located on chromosome 9p21, encodes two cell-cycle regulatory proteins, p16(INK4a) and p14(ARF), acting through the Rb-CDK4 and p53 pathways. To study the contribution of each pathway in the tumourigenesis of cholangiocarcinoma, the alterations of p14(ARF), p16(INK4a), p53, and pRb were analysed. After microdissection, DNAs from 51 cholangiocarcinomas were analysed by methylation-specific PCR (MSP), restriction-enzyme related polymerase chain reaction (RE-PCR), microsatellite analysis, mRNA expression, and DNA sequencing.

Measurement of 4-hydroxylation of ifosfamide in human liver microsomes using the estimation of free and protein-bound acrolein and codetermination of keto- and carboxyifosfamide.

Purpose: The aim of the present study was to determine the turnover (4-hydroxylation and N-dechloroethylation) of ifosfamide in a total of 25 human liver microsomal preparations in which the codetermination of keto- and carboxyifosfamide as well as the calculation of free and protein-bound acrolein was carried out for the first time.

Methods: The 4-hydroxylation of ifosfamide was estimated by using acrolein (free and protein-bound) and a newly developed procedure involving the codetermination of keto- and carboxyifosfamide (LC/MS). The ifosfamide N-dechloroethylation was determined as the sum of 2- and 3-dechloroethylifosfamide (LC/MS).

Quality of life in chronic pancreatitis: a prospective trial comparing classical whipple procedure and duodenum-preserving pancreatic head resection.

Few data are available with respect to quality of life after pancreatic head resection in patients with chronic pancreatitis. The aim of this study was to compare the classical Whipple pancreatoduodenectomy (PD) with the Beger duodenum-preserving pancreatic head resection (DPPHR), in terms of quality of life, using standardized, valid, and reliable questionnaires. Sixty-five consecutive patients were included in this study.

Neuroendocrine tumours of the duodenum. Clinical aspects, pathomorphology and therapy.

Background And Aims: Neuroendocrine tumours (NTs) of the duodenum are uncommon neoplasms. They represent a heterogeneous spectrum of subtypes and may be associated with von Recklinghausen's disease type I (VRD) and multiple endocrine neoplasia type I. There are few studies concerning the biological characteristics and adequate therapy of these tumours.

Prospective evaluation of circulating hepatocytes by alpha-fetoprotein messenger RNA in patients with hepatocellular carcinoma.

Background: The significance of alpha-fetoprotein (AFP) messenger RNA as a surrogate marker for isolated tumor cells in the blood of patients with hepatocellular carcinoma (HCC) is controversial. Our goals were to correlate AFP mRNA with tumor recurrence and overall survival after patients with HCC received curative operations and to analyze AFP mRNA findings in control patients.

Methods: In this prospective controlled study, RNA was purified from the blood of 85 patients with HCC before, during, and after therapy and from 116 control patients.