Rho kinases regulate endothelial invasion and migration during valvuloseptal endocardial cushion tissue formation.

Rho-associated kinase (ROCK) is a downstream effector of small Rho-GTPases, and phosphorylates several substrates to regulate cell functions, including actin cytoskeletal reorganization and cellular motility. Endothelial-mesenchymal transformation (EMT) is a critical event in the formation of valves and septa during cardiogenesis. It has been reported that ROCK plays an important role in the regulation of endocardial cell differentiation and migration during mouse cardiogenesis (Zhao and Rivkees [2004] Dev. Biol. 275:183-191). Immunohistochemistry showed that, during chick cardiogenesis, ROCK1 and -2 were expressed in the transforming and migrating endothelial/mesenchymal cells in the outflow tract (OT) and atrioventricular (AV) canal regions from which valvuloseptal endocardial cushion tissue would later develop. Treatment with Y27632, a specific ROCK inhibitor, of cultured AV explants or AV endothelial monolayers of stage 14-minus heart (preactivated stage for EMT) on three-dimensional collagen gel perturbed the seeding of mesenchymal cells into the gel lattice. In these experiments, Y27632 did not suppress the expression of an early transformation marker, smooth muscle alpha-actin. Moreover, Y27632 inhibited the mesenchymal invasion in stage 14-18 AV explants, in which endothelial cells had committed to undergo EMT. ML-9, a myosin light chain kinase inhibitor, also inhibited the mesenchymal invasion in cultured AV explants. These results suggest that ROCKs have a critical role in the mesenchymal cell invasion/migration that occurs at the late onset of EMT.     

Estimation of postoperative fat absorption using the <Superscript>13</Superscript>C mixed-triglyceride breath test in children with choledochal cyst

No previous studies have focused on postoperative fat malabsorption in children with choledochal cyst (CC) who undergo cyst excision and Roux-en-Y (RY) hepatico–jejunostomy (HJ), a combination of procedures that can lead to the non-physiological mixture of food and bile juice. To examine the effect of RYHJ with cholecystectomy on the fat absorption ability of children with CC, we estimated postoperative fat-absorption ability using the carbon 13-labeled mixed triglyceride (¹³C-MTG) breath test. Twelve postoperative children with CC and 12 normal control children were administered ¹³C-MTG orally and asked to give breath samples at six time points: once before the ¹³C-MTG ingestion and at five 60-min intervals post-ingestion. Fecal chymotrypsin activity and fecal fat excretion were also measured. The delta value of breath ¹³CO₂ at 3, 4, and 5 h after administration and the 5-h cumulative breath ¹³CO₂ were significantly lower in the CC children than in the controls. There were no significant differences in the fecal chymotrypsin activity or fecal fat excretion of the two groups. Conclusion. Occult fat malabsorption occurs in patients with CC after RYHJ, even in the absence of clinical symptoms or abnormal laboratory data.     

Clinicopathological significant and prognostic influence of cadherin-17 expression in gastric cancer

Cadherin-17 (CDH17), also called liver–intestine cadherin, is a structurally unique member of the cadherin superfamily. Our serial analysis of gene expression demonstrated that CDH17 was one of the most up-regulated genes in advanced gastric carcinomas. CDH17 expression is known to be regulated by Cdx2. In the present study, we examined the expression of CDH17 in primary gastric carcinoma tissues by immunohistochemistry, and analyzed the correlation of CDH17 expression with clinicopathological characteristics and patients prognosis. CDH17 expression was detected in 63/94 (67%) of gastric adenocarcinomas in addition to intestinal metaplasia. The expression of CDH17 tended to be associated with intestinal type carcinoma, and carcinomas with CDH17 expression was significantly more frequent in advanced stage cases (80%) than in early stage (53%). The prognosis of patients with positive CDH17 expression was significantly poorer than that of the negative cases (P=0.0314). However, multivariate analysis revealed that CDH17 was not an independent prognostic factor. Six of seven cases that showed positive expression of Cdx2 simultaneously expressed CDH17 protein. These results suggested that the expression of CDH17 was characteristic of the advanced gastric carcinoma that is associated with poor prognosis.     

Asymptomatic high Epstein-Barr viral load carriage in pediatric renal transplant recipients

High viral load carriage of EBV is one of the risks for PTLD in transplant recipients. We reviewed retrospectively in pediatric renal transplant recipients with EBV seronegative. EBV loads in peripheral blood and EBV-CTLs were measured every 1-3 months in 13 patients after grafting. Immunosuppressants were reduced when the patients were considered to have persistent high EBV loads (>1000 copies/μgDNA for over six months). All showed primary EBV infection: six with asymptomatic persistent high EBV loads (group A) and seven with neither EBV-associated symptoms nor persistent high EBV loads (group B). No patient developed PTLD in either group. Chronic rejection occurred in one patient in group A after immunosuppressants' reduction. There was no difference in renal dysfunction rates between the two groups. The maximum and increase rates in EBV loads were significantly higher in group A. The CTLs' percentage was significantly lower in group A when EBV loads first rose above 100 copies/μg DNA. This study suggests the possibility that EBV loads and CTLs' monitoring may be useful for avoidance of PTLD, as patients with asymptomatic persistent high EBV loads had higher EBV loads and lower percentages of CTLs.     

Unique three-way translocation, t(3;14;18)(q27;q32;q21), in follicular lymphoma

A 43-year-old woman was diagnosed as having stage IV follicular lymphoma. Phenotypically, the lymphoma cells were CD5(-), CD10(+), CD19(+), CD20(+), CD23(-), HLA-DR(+), and IgM-lambda(+). Conventional chromosomal analysis showed a three-way t(3;14;18)(q27;q32;q21) in the lymphoma cells, which was confirmed by spectral karyotyping (SKY) and fluorescence in situ hybridization (FISH). Immunohistochemistry revealed that both BCL2 and BCL6 proteins were expressed in the lymphoma cells, whereas only the BCL6 gene, and not the BCL2 gene, was rearranged by Southern blotting. The patient received combination chemotherapy and has been well for 3 years. This is the first reported case showing a three-way translocation involving 2 major lymphoma-specific abnormalities, 3q27 and t(14;18)(q32;q21).     

Ethnic differences in allele frequency of autoimmune-disease-associated SNPs

Several multiple, large-scale, genetic studies on autoimmune-disease-associated SNPs have been reported recently: peptidylarginine deiminase type 4 (PADI4) in rheumatoid arthritis (RA); solute carrier family 22 members 4 and 5 (SLC22A4 and 5) in RA and Crohns disease (CD); programmed cell death 1 (PDCD1) in systemic lupus erythematosus (SLE), type 1 diabetes mellitus (T1D), and RA; and protein tyrosine phosphatase nonreceptor type 22 (PTPN22) in T1D, RA, and SLE. Because these reports on association were not always evaluated in multiple ethnic groups and because ethnic difference in allele frequency of the variants has been also reported, we investigated allele frequencies of nine SNPs in four autoimmune-disease-associated loci in Caucasian, African-descent, and Japanese populations. Although SNPs in PADI4 had similar allele frequency among three groups [maximal difference 11%; (P >0.05)], the other three loci revealed statistically significant allele frequency differences (maximal difference 39% (P <0.00001), 13% (P <0.00001), and 8% (P <0.00001) in SLC22A4, PDCD1, and PTPN22, respectively). Of note, three SNPs in the three loci that had allele frequency more than 8% in the Caucasian population were either not polymorphic at all or extremely rare in the Japanese population. Our data suggest that ethnic variations of polymorphisms should be evaluated in detail, and differences should be incorporated into investigations of susceptibility variants for common diseases.     

Camostat mesilate attenuates pancreatic fibrosis via inhibition of monocytes and pancreatic stellate cells activity

Camostat mesilate (CM), an oral protease inhibitor, has been used clinically for the treatment of chronic pancreatitis in Japan. However, the mechanism by which it operates has not been fully understood. Our aim was to evaluate the therapeutic efficacy of CM in the experimental pancreatic fibrosis model induced by dibutyltin dichloride (DBTC), and we also determined the effect of CM on isolated monocytes and panceatic stellate cells (PSCs). In vivo, chronic pancreatitis was induced in male Lewis rats by single administration of 7 mg/kg DBTC and a special diet containing 1 mg/g CM was fed to the DBTC+CM-treated group from day 7, while the DBTC-treated group rats were fed a standard diet. At days 0, 7, 14 and 28, the severity of pancreatitis and fibrosis was examined histologically and enzymologically in both groups. In vitro, monocytes were isolated from the spleen of a Lewis rat, and activated with lipopolysaccharide stimulation. Thereafter, the effect of CM on monocyte chemoattractant protein-1 (MCP-1) and tumor necrosis factor-alpha (TNF-alpha) production from monocytes was examined. Subsequently, cultured rat PSCs were exposed to CM and tested to see whether their proliferation, MCP-1 production and procollagen alpha1 messenger RNA expression was influenced by CM. In vivo, the oral administration of CM inhibited inflammation, cytokines expression and fibrosis in the pancreas. The in vitro study revealed that CM inhibited both MCP-1 and TNF-alpha production from monocytes, and proliferation and MCP-1 production from PSCs. However, procollagen alpha1 expression in PSCs was not influenced by CM. These results suggest that CM attenuated DBTC-induced rat pancreatic fibrosis via inhibition of monocytes and PSCs activity.     

Clinical usefulness of urinary diacetylpolyamines as novel tumor markers

N1,N12-Diacetylspermine(DiAcSpm) and N1,N8-diacetylspermidine(DiAcSpd) are excreted in the urine of healthy persons as minor components of urinary polyamine, with small individual variations in amount. They are promising tumor markers, since their excretion is frequently elevated in patients with various types of cancers. DiAcSpm is sensitive in cancer detection, while DiAcSpd is highly specific for cancer. Diacetylpolyamines were initially characterized and determined by HPLC fractionation, followed by enzymatic detection. More recently, antibodies highly specific for DiAcSpm and DiAcSpd were developed, and an ELISA system applicable to the determination of urinary DiAcSpm was established. Measurement of urinary DiAcSpm using this ELISA system revealed that DiAcSpm is a more sensitive tumor marker than CEA, CA19-9 and CA15-3 for colon and breast cancers. More importantly, DiAcSpm efficiently detects patients at early stages. On the other hand, CEA, CA19-9 and CA15-3 are quite insensitive for early stage cancers. The urinary DiAcSpm level tends to remain low even in tumor-bearing individuals when their cancerous lesions remain static, while it rises rapidly concomitant with recurrence. DiAcSpm may serve as a prognostic indicator and marker for recurrence of prostate and colon cancers. Diacetylpolyamines may turn out to be general tumor markers, since active proliferation of any cancer tissues would likely be accompanied by activation of polyamine metabolism.     

Urinary leukotriene E4 in Henoch–Schonlein purpura

BACKGROUND: Children with Henoch-Schonlein purpura (HSP) occasionally have allergic disease. We have previously shown that pranlukast hydrate was effective for purpura in HSP. Pranlukast hydrate is a leukotriene (LT) receptor antagonist; therefore, it is likely that LTs take part in the cause of HSP. Urinary leukotriene E4 (LTE4u) levels are a useful index of whole-body cysteinyl LT production in vivo. In this study, LTE4u was examined in children with HSP. OBJECTIVE: The purpose of this study was to examine the relation between the level of LTE4u and the cause of HSP. METHODS: Eighteen HSP children (six boys and 12 girls) and six healthy children were enrolled. RESULTS: LTE4u levels in patients with HSP were significantly higher (P< 0.05) at the onset than those in healthy children. Four weeks therapy with pranlukast hydrate lowers LTE4u levels in patients with HSP (P< 0.05). There were no differences in LTE4u between the group of HSP patients with purpura nephritis and the group of HSP patients without purpura nephritis. CONCLUSION: These results indicate that csyteinyl LTs may play a role in the pathophysiology of purpura in HSP.