Serum S100B indicates brain edema formation and predicts long-term neurological outcomes in rat transient middle cerebral artery occlusion model

To assess the usefulness of serum S100B as a biomarker, the present study proceeded by observing serum S100B kinetics in a rat transient middle cerebral artery occlusion (MCAO) model, then assessed the correlation between serum S100B and both brain edema formation and neurological outcomes. Study results showed increases in serum S100B concentrations, peaking 48 h after MCAO. Brain water content in the ipsilateral hemisphere significantly increased from 24 h after MCAO, and reached peak value 72 h after MCAO. A single measurement of serum S100B 48 h after MCAO showed significant correlations with maximal extent of brain edema 72 h after MCAO. Furthermore, S100B concentrations 48 h after MCAO significantly correlated with infarct volumes. Neurological outcomes were estimated in a long-term study, where a gradual recovery was observed up to 168 h after MCAO. Serum S100B 48 h after MCAO was found to show higher correlation with neurological score 168 h after MCAO than those 48 h after MCAO. These findings suggest that serum S100B is an effective biomarker in predicting both extent of brain edema and long-term neurological outcomes in a rat transient MCAO model.     

In vivo pharmacokinetics of ketoprofen after patch application in the Mexican hairless pig

To evaluate the pharmacokinetics of topical drugs, in vitro permeation studies are performed using sacrificed pig skin or human tissues resected at surgery; however, these methods have their limitations in in vivo pharmacokinetics. This study examined the usefulness of Mexican hairless pigs for in vivo pharmacokinetic study, especially the drug concentration in the tissues. A ketoprofen patch was applied on the back of Mexican hairless pigs for 24 h, followed by sequential collection of blood specimens from 0 to 36 h (n=3). Also, the skin, subcutaneous fat, fascia and muscle from the center of the site of application were excised at 12 h after the application (n=4). Ketoprofen was first detected in the plasma at 8 h, the concentration increasing up to 24 h; the plasma concentration began to decrease after the removal of the ketoprofen patch. Ketoprofen concentrations in the tissues decreased with increasing depth of the tissues, but the values in the deep muscles, being the lowest among the tissues examined, were still higher than those in the plasma. While the data of drug concentration in human tissue are difficult to test, the Mexican hairless pig model appears to be attractive for in vivo pharmacokinetic studies of topically applied ketoprofen. Copyright © 2009 John Wiley & Sons, Ltd.     

MEK Activation Suppresses CPT11-Induced Apoptosis in Rat Intestinal Epithelial Cells Through a COX-2-Dependent Mechanism

Resistance to chemotherapeutic agents is one of the distinct features of cancer cells. We evaluate the role of activated MEK-ERK signaling in Camptotecin/irinotecan (CPT-11)-induced cell death using constitutively activated MEK1-transfected normal rat intestinal epithelial cells (IEC-caMEK cells). A CPT-11-induced inhibitory concentration of 50% was determined by WST assay. Apoptosis was evaluated by DNA staining and fragmented DNA analysis. Protein expressions were analyzed by western blotting. We also examined the role of cyclooxygenase-2 in the cell systems. IEC-caMEK cells possessed survival advantages compared to control cells. Apoptosis was remarkably suppressed in IEC-caMEK cells. Western blot analysis revealed increased expression of Bcl-2, Bcl-xL, Mcl-1, and COX-2 and decreased expression of Bak in IEC-caMEK cells. The COX-2 selective inhibitor ameliorated the antiapoptotic nature of IEC-caMEK cells. MEK activation suppressed CPT-11-induced apoptosis in IEC-caMEK cells via a COX-2- dependent mechanism. Therefore, MEK-ERK signaling may contribute to the drug-resistant nature of cancer cells.     

Serum vascular endothelial growth factor in cyanotic congenital heart disease functionally contributes to endothelial cell kinetics in vitro

BackgroundRemarkable amounts of neovascularization develop in patients with cyanotic congenital heart disease who have low pulmonary blood flow and systemic cyanosis, but the factors functionally responsible for angiogenesis in cyanotic congenital heart disease have not been determined.Methods and resultsTo investigate the functional angiogenic molecules in serum from these patients, serum angiogenic activity was studied in 21 patients (systemic oxygen saturation: 82 ± 1.9%) and in 17 healthy controls. Patient serum was more active in stimulating the tube formation of human umbilical vein endothelial cells (HUVECs) into capillary-like structures than control serum (150% vs 104% of internal control; p < 0.001). This increased serum angiogenic activity normalized after total cardiac repair (p < 0.001). The migration activity of HUVECs was also accelerated in patient serum (p = 0.007). To identify the molecules in patient serum affecting tube formation of HUVECs, we examined the effects of an inhibitor or a neutralizing antibody against various angiogenic molecules on in vitro angiogenesis. Both the soluble vascular endothelial growth factor (VEGF) receptor 1 and the VEGF receptor 2 tyrosine kinase inhibitor SU5416 reduced the basal serum angiogenic activity of patients and this was reversed by a supplement of recombinant human VEGF.ConclusionOur results indicate that serum VEGF functionally contributes to vascular endothelial cell kinetics in patients with cyanotic congenital heart disease.     

Factors associated with improvement of fasting plasma glucose level by mealtime dosing of a rapid-acting insulin analog in type 2 diabetes

This study investigated whether strict control of plasma glucose levels with mealtime dosing of a rapid-acting insulin analog improves early morning fasting plasma glucose (FPG) levels in patients with type 2 diabetes. A rapid-acting insulin analog was administered at each mealtime to 40 Japanese patients with type 2 diabetes whose existing antidiabetic medication was discontinued. Approximately one-half (52.5%) of the patients achieved a minimum early morning FPG levels achievable (nadir FPG) of <120mg/dL with mealtime dosing of a rapid-acting insulin analog alone; no basal insulin replacement was needed in these patients. Nadir FPG levels were independent of duration of diabetes, baseline body mass index (BMI) or glycemic control. All patients who had been treated with sulfonylureas needed basal insulin replacement. Low responses of insulin to glucagon and to arginine, and high response of glucagon to arginine may explain the failure to improve FPG levels with postprandial insulin replacement alone. In conclusion, approximately one-half of the patients with type 2 diabetes achieved appropriate control of FPG by rapid-acting insulin analog monotherapy. Basal insulin secretory defects in type 2 diabetes may be estimated by the responses of insulin to glucagon and to arginine and the response of glucagon to arginine. This study contributes to a better understanding of the pathophysiology contributing to the heterogeneity in the characteristics of insulin secretion in type 2 diabetes.     

Oxidative stress induces the endoplasmic reticulum stress and facilitates inclusion formation in cultured cells

BACKGROUND/AIMS: The precise mechanism of formation and significance of Mallory bodies (MBs) are poorly understood. The endoplasmic reticulum (ER) is the organelle responsible for proper folding and elimination of unfolded proteins. Therefore, failure of this function increases defective proteins in the cell. METHODS: We examined the effects of oxidative stress on induction of ER stress and keratin 8 and 18 (K8/18)-containing inclusion formation in cultured human hepatoma cells and hepatocytes by immunofluorescence and immunoblot analyses. RESULTS: Generation of H(2)O(2) was detected in glucose oxidase (GO)-treated cells by 2',7'-dichlorodihydrofluorescein diacetate and co-treatment with GO and acetyl-leucyl-leucyl-norleucinal (ALLN), a proteasome inhibitor, induced formation of extensive keratin inclusions that were inhibited by pre-treatment with N-acetyl-cysteine. These inclusions shared similar features with MBs by immunofluorescence analysis. Electron microscopy showed that these structures appeared near the nuclei, surrounded by filamentous structures. GO and ALLN upregulated the expression of ER stress markers, however, 4-phenylbutyrate, a chemical chaperone, reduced formation of inclusions and expression of the ER stress markers. CONCLUSIONS: The oxidative stress coupled with limited inhibition of the proteasome induces dysfunction of the ER and results in inclusion formation in cultured cells. This suggests that ER stress plays a role in MB formation in liver disease.     

Hyperbaric oxygen therapy for the treatment of postoperative paralytic ileus and adhesive intestinal obstruction associated with abdominal surgery: experience with 626 patients

BACKGROUND/AIMS: The results of hyperbaric oxygen (HBO) therapy for treatment of postoperative paralytic ileus and adhesive intestinal obstruction associated with abdominal surgery are unknown. METHODOLOGY: A retrospective review of postoperative paralytic ileus and adhesive intestinal obstruction associated with abdominal surgery in 626 patients required 758 admissions who underwent HBO therapy was undertaken to examine the efficacy of HBO therapy. RESULTS: The overall resolution rates for patients receiving HBO therapy in cases of postoperative paralytic ileus and adhesive intestinal obstruction were 92% and 85%, respectively. Among patients who were more than 75 years old, the therapies resolved 35 (97%) of 36 cases of postoperative paralytic ileus and 42 (81%) of 52 cases of adhesive intestinal obstruction, which was comparable to the results for patients less than 75 years old. The mortality rate was 1.2% overall. Complications related to HBO therapy occurred in 3.8% of the admissions, and most of them were not serious. CONCLUSIONS: These results suggest that HBO therapy might deserve further assessment for use in management of postoperative paralytic ileus and adhesive intestinal obstruction as a new modality. HBO therapy is safe and non-invasive, and may be useful in the elderly patients, since mortality was relatively low in this series.     

DMY gene induces male development in genetically female (XX) medaka fish

Although the sex-determining gene SRY/Sry has been identified in mammals, homologues and genes that have a similar function have yet to be identified in nonmammalian vertebrates. Recently, DMY (the DM-domain gene on the Y chromosome) was cloned from the sex-determining region on the Y chromosome of the teleost fish medaka (Oryzias latipes). DMY has been shown to be required for the normal development of male individuals. In this study, we show that a 117-kb genomic DNA fragment that carries DMY is able to induce testis differentiation and subsequent male development in XX (genetically female) medaka. In addition, overexpression of DMY cDNA under the control of the CMV promoter also caused XX sex reversal. These results demonstrate that DMY is sufficient for male development in medaka and suggest that the functional difference between the X and Y chromosomes in medaka is a single gene. Our data indicate that DMY is an additional sex-determining gene in vertebrates.     

Hypertension and dysregulated proinflammatory cytokine production in receptor activity-modifying protein 1-deficient mice

Calcitonin gene-related peptide (CGRP) is thought to be a prominent neuropeptide in cardiovascular regulation and neuroimmune modulation. There are two isoforms of CGRP (alphaCGRP and betaCGRP), and the main CGRP receptors are probably composed of a calcitonin receptor-like receptor (CLR) and a receptor activity-modifying protein (RAMP)1. However, the physiological functions of CGRP that are mediated through the CLR/RAMP1 receptors remain to be clarified. For an improved understanding of the functions, we generated mice deficient in RAMP1, a specific subunit of CGRP receptors, by a conditional gene-targeting technique. The RAMP1-deficient mice (RAMP1(-/-)) exhibited high blood pressure, with no changes in heart rate. alphaCGRP was found to have a potent vascular relaxant activity compared with betaCGRP in the artery of the WT (RAMP1(+/+)) mice. The activities of both CGRP isoforms were remarkably suppressed in the arteries of the RAMP1(-/-) mice. The LPS-induced inflammatory responses of the RAMP1(-/-) mice revealed a transient and significant increase in the serum CGRP levels and high serum levels of proinflammatory cytokines compared with the RAMP1(+/+) mice. alphaCGRP and betaCGRP equally suppressed the production of TNF-alpha and IL-12 in bone marrow-derived dendritic cells stimulated with lipopolysaccharide. Their inhibitory effects were not observed in the bone marrow-derived dendritic cells of the RAMP1(-/-) mice. These results indicate that CGRP signaling through CLR/RAMP1 receptors plays a crucial role in the regulation of both blood pressure by vascular relaxation and proinflammatory cytokine production from dendritic cells.