Hepatitis C virus-specific CD4+ T cell response after liver transplantation occurs early, is multispecific, compartmentalizes to the liver, and does not correlate with recurrent disease

The role of hepatitis C virus (HCV)-specific CD4+ T cells in recurrent HCV infection after orthotopic liver transplantation (OLTx) is unclear. In parallel, 73 intrahepatic and 73 blood-derived T cell lines were established from 34 patients. At a single cell level, virus-specific interferon (IFN)-gamma production to various HCV proteins was determined by ELISPOT assay: 45 (62%) of 73 liver- or blood-derived T cell lines produced IFN-gamma in response to one of the HCV antigens. HCV specificity was detected mainly in the liver (47% vs. 23% in the blood; P<.05, chi(2) test) and was detectable earlier (< or =6 months) significantly more often than later (>6 months) after OLTx (78% vs 49%; P<.05, chi(2) test). Histology, histologic activity index, liver enzymes, and virus load did not correlate with the occurrence of HCV-specific CD4+ T cells. Despite strong immunosuppressive treatment, OLTx recipients can develop an early, multispecific, preferentially intrahepatic CD4+ T cell response that decreases over time, making it a potential candidate target for novel therapeutic approaches in the transplant setting.     

Sunitinib for Taiwanese patients with gastrointestinal stromal tumor after imatinib treatment failure or intolerance

AIM:To report preliminary results of the efficacy and safety of sunitinib in the management of Taiwanese gastrointestinal stromal tumors (GIST) patients facing imatinib mesylate (IM) intolerance or failure.METHODS:Between 2001 and May 2010,199 Taiwanese patients with metastatic GIST were treated at Chang Gung Memorial Hospital.Among them,23 (11.6%) patients receiving sunitinib were investigated.RESULTS:Sixteen male and 7 female patients with a median age of 59 years (range:24-83 years) received sunitinib.Tw...     

Further observations upon gastric function in rats after prolonged administration of an anticholinergic drug,propantheline bromide

Gastric function was assessed in Wistar rats which received propantheline bromide by daily injection for 20 weeks. The results were compared with those from two control groups, one of which was injected daily with saline for 20 weeks. Gastric acid secretion, as measured by test meal and after ligation of the pylorus, was similar in all three groups. Acid secretion, as measured by test meal with pentagastrin 100 µg/kg body weight, gastric emptying, and fundic mucosal volume, expressed in terms of body weight, were all significantly increased in rats given propantheline. Only those measurements of acid secretion obtained by test meal with pentagastrin showed a significant correlation with fundic mucosal volume. Hence, since this method provides the most accurate indication of secretory capacity, it is concluded that the prolonged parenteral administration of propantheline may lead to an increase in parietal cell mass and its correlate, maximal secretory capacity. The mechanism by which these changes are produced is obscure.The author is grateful to Mr. Howard Ireson for his expert technical assistance, and to Mr. Ralph Marshall, Department of Medical Illustration, Cardiff Royal Infirmary, for the photography employed.Propantheline bromide (Pro-Banthine) was generously supplied by G. D. Searle and Co., Ltd.     

Transcatheter electrosurgery in bipolar or monopolar modes

• Transcatheter electrosurgery has emerging value in a range of other new procedures that require traversing tissue (transcaval access, transcatheter Glenn Shunt) or slicing tissue (LAMPOON slicing of the mitral valve and BASILICA slicing of the aortic valve).
• This is the first report of bipolar radiofrequency wires used to cross lesions in humans, reported here in seven re‐entry CTO cases.
• The bipolar configuration may provide directionality to charge without need for wire alignment and advancement, but is theoretically disadvantageous for tissue “cutting” because of problems with charge concentration.

     

CSF proteome analysis in clinically isolated syndrome (CIS): Candidate markers for conversion to definite multiple sclerosis

Cerebrospinal fluid (CSF) is a promising source of biomarkers in clinically isolated syndrome (CIS), which frequently presents as a first episode of multiple sclerosis (MS). Using the two-dimensional difference in gel electrophoresis (2-D DIGE), we compared CSF samples from patients with CIS that remained CIS (CIS-CIS, n = 8) over a follow-up time of 2 years and from patients with CIS that developed definite MS of the relapsing-remitting subtype (CIS-RRMS, n = 8) over the same period. Protein spots that showed significant differences between patients and controls were selected for further analysis by MALDI-TOF mass spectrometry. For validation of identified spots ELISA experiments were performed. We identified one protein that was upregulated in CIS-RRMS (serin peptidase inhibitor) and eight proteins (alpha-1-B-glycoprotein, Fetuin-A, apolipoprotein A4, haptoglobin, human Zinc-alpha-2-glycoprotein (ZAG), Retinol-binding protein, superoxid dismutase 1, transferrin) that were down-regulated in CIS-RRMS vs. CIS-CIS. For Fetuin-A, our findings could be confirmed by ELISA. The pathophysiological role as well as clinical relevance of these candidate proteins in CIS remains to be further clarified by future studies.     

p.R254Q mutation in the aquaporin‐2 water channel causing dominant nephrogenic diabetes insipidus is due to a lack of arginine vasopressin‐induced phosphorylation

Vasopressin regulates human water homeostasis by re‐distributing homotetrameric aquaporin‐2 (AQP2) water channels from intracellular vesicles to the apical membrane of renal principal cells, a process in which phosphorylation of AQP2 at S256 by cAMP‐dependent protein kinase A (PKA) is thought to be essential. Dominant nephrogenic diabetes insipidus (NDI), a disease in which the kidney is unable to concentrate urine in response to vasopressin, is caused by AQP2 gene mutations. Here, we investigated a reported patient case of dominant NDI caused by a novel p.R254Q mutation. Expressed in oocytes, AQP2‐p.R254Q appeared to be a functional water channel, but was impaired in its transport to the cell surface to the same degree as AQP2‐p.S256A, which mimics non‐phosphorylated AQP2. In polarized MDCK cells, AQP2‐p.R254Q was retained and was distributed similarly to that of unstimulated wt‐AQP2 or AQP2‐p.S256A. Upon co‐expression, AQP2‐p.R254Q interacted with, and retained wt‐AQP2 in intracellular vesicles. In contrast to wild‐type AQP2, forskolin did not increase AQP2‐p.R254Q phosphorylation at S256 or its translocation to the apical membrane. Mimicking constitutive phosphorylation in AQP2‐p.R254Q with the p.S256D mutation, however, rescued its apical membrane expression. These date indicate that a lack of S256 phosphorylation is the sole cause of dominant NDI here, and thereby, p.R254Q is a loss of function instead of a gain of function mutation in dominant NDI. © 2009 Wiley‐Liss, Inc.     

Bone marrow mesenchymal stem cells undergo nemosis and induce keratinocyte wound healing utilizing the HGF/c-Met/PI3K pathway

We previously showed cell–cell contacts of human dermal fibroblasts to induce expression of the hepatocyte growth factor/scatter factor (HGF) in a process designated as nemosis. Now we report on nemosis initiation in bone marrow mesenchymal stem cells (BMSCs). Because BMSCs are being used increasingly in cell transplantation therapy we aimed to demonstrate a functional effect and benefit of BMSC nemosis for wound healing. Nemotic and monolayer cells were used to stimulate HaCaT keratinocyte migration in a scratch-wound healing assay. Both indicators of nemosis, HGF production and cyclooxygenase-2 expression, were induced in BMSC spheroids. When compared with a similar amount of cells as monolayer, nemotic cells induced keratinocyte in vitro scratch-wound healing in a concentration-dependent manner. The HGF receptor, c-Met, was rapidly phosphorylated in the nemosis-stimulated keratinocytes. Nemosis-induced in vitro scratch-wound healing was inhibited by an HGF-neutralizing antibody as well as the small molecule c-Met inhibitor, SU11274. HGF-induced in vitro scratch-wound healing was inhibited by PI3K inhibitors, wortmannin and LY294002, while LY303511, an inactive structural analogue of LY294002, had no effect. Inhibitors of the mitogen-activated protein kinases MEK/ERK1/2 (PD98059 and U0126), and p38 (SB203580) attenuated HGF-induced keratinocyte in vitro scratch-wound healing. We conclude that nemosis of BMSCs can induce keratinocyte in vitro scratch-wound healing, and that in this effect signaling via HGF/c-Met is involved.