Increased expression of interleukin 17 in inflammatory bowel disease

BACKGROUND AND AIM

Interleukin (IL) 17 is a cytokine which exerts strong proinflammatory activities. In this study we evaluated changes in IL-17 expression in the inflamed mucosa and in the serum of patients with inflammatory bowel disease (IBD).

METHODS

Tissue samples were obtained endoscopically or surgically from patients with ulcerative colitis (UC) (n=20), Crohn's disease (CD) (n=20), infectious colitis (n=5), ischaemic colitis (n=8), and normal colorectal tissues (n=15). IL-17 expression was evaluated by a standard immunohistochemical procedure. Serum IL-17 levels were determined by ELISA. IL-17 mRNA expression was analysed by reverse transcriptase-polymerase chain reaction.

RESULTS

IL-17 expression was not detected in samples from normal colonic mucosa, infectious colitis, or ischaemic colitis. In the inflamed mucosa of active UC and CD patients, IL-17 expression was clearly detectable in CD3(+) T cells or CD68(+) monocytes/macrophages. The average number of IL-17(+) cells was significantly increased in active UC and CD patients compared with inactive patients. IL-17 mRNA expression was not detected in normal mucosa but was detectable in the mucosa from active UC and CD patients. IL-17 was not detected in the sera from normal individuals, infectious colitis, or ischaemic colitis patients but IL-17 levels were significantly elevated in IBD patients.

CONCLUSIONS

IL-17 expression in the mucosa and serum was increased in IBD patients. It is likely that IL-17 expression in IBD may be associated with altered immune and inflammatory responses in the intestinal mucosa.

Impact of sarcopenia on survival in patients undergoing living donor liver transplantation

Skeletal muscle depletion, referred to as sarcopenia, predicts morbidity and mortality in patients undergoing digestive surgery. However, the impact on liver transplantation is unclear. The present study investigated the impact of sarcopenia on patients undergoing living donor liver transplantation (LDLT). Sarcopenia was assessed by a body composition analyzer in 124 adult patients undergoing LDLT between February 2008 and April 2012. The correlation of sarcopenia with other patient factors and the impact of sarcopenia on survival after LDLT were analyzed. The median ratio of preoperative skeletal muscle mass was 92% (range, 67-130%) of the standard mass. Preoperative skeletal muscle mass was significantly correlated with the branched-chain amino acids to tyrosine ratio (r = -0.254, p = 0.005) and body cell mass (r = 0.636, p < 0.001). The overall survival rate in patients with low skeletal muscle mass was significantly lower than in patients with normal/high skeletal muscle mass (p < 0.001). Perioperative nutritional therapy significantly increased overall survival in patients with low skeletal muscle mass (p = 0.009). Multivariate analysis showed that low skeletal muscle mass was an independent risk factor for death after transplantation. In conclusion, sarcopenia was closely involved with posttransplant mortality in patients undergoing LDLT. Perioperative nutritional therapy significantly improved overall survival in patients with sarcopenia.

Novel single-balloon enteroscopy for diagnosis and treatment of the small intestine: preliminary experiences

BACKGROUND AND AIM

As a tool for examining the small intestine, double-balloon enteroscopy (DBE) has been used routinely. However, there remain a few issues relating to the handling of DBE, such as attaching a balloon to the tip of the scope, and inflating/deflating the two balloon systems. Recently, we developed a novel single-balloon enteroscopy (SBE) system for the examination of the small intestine. The aim of the present study was to evaluate the insertion technique, the safety, and the clinical impact of the SBE system.

PATIENTS AND METHODS

Between January 2006 and June 2007, all patients undergoing enteroscopy with the Olympus SBE system (length 200 cm, outer diameter 9.2 mm) were studied. Instead of a balloon attached to the distal scope end, the distal scope end was hook-shaped, and manipulating the up-angle or down-angle of the scope end enabled exploration of the small intestine.

RESULTS

A total of 78 procedures were performed in 41 patients (24 men, 17 women; mean age 48.9 years, range 23 - 85 years). The indications for the examination were suspected mid-gastrointestinal bleeding (n = 12), Crohn's disease (n = 17), abdominal pain (n = 8), and abdominal tumor (n = 4). The mean procedure time was 62.8 +/- 20.2 minutes and 70.4 +/- 19.3 minutes for the oral and anal routes, respectively. Among 24 patients in whom total enteroscopy was attempted, the entire small intestine was explored in 6.

CONCLUSION

SBE is not only easy to perform, due to the single balloon, but it can also safely examine the deep small intestine. Therefore, SBE may be a useful diagnostic and therapeutic tool in addition to DBE for investigating suspected small bowel disease.

Dietary supplementation with fish oil rich in omega-3 polyunsaturated fatty acids in children with bronchial asthma

Omega-3 polyunsaturated fatty acids have anti-inflammatory effects in vitro, and high dietary levels are associated with a lower incidence of inflammatory diseases. However, only limited effects have been demonstrated in asthma. The effects of dietary supplementation with fish oil for 10 months in 29 children with bronchial asthma was investigated in a randomized controlled fashion. In order to minimize the effects of environmental inhaled allergens and diet, this study was performed in a long-term treatment hospital. Subjects received fish oil capsules containing 84 mg eicosapentaenoic acid (EPA) and 36 mg docosahexaenoic acid (DHA) or control capsules containing 300 mg olive oil. The daily dosages of EPA and DHA were 17.0-26.8 and 7.3-11.5 mg x kg body weight(-1), respectively. Asthma symptom scores decreased and responsiveness to acetylcholine decreased in the fish oil group but not in the control group. In addition, plasma EPA levels increased significantly only in the fish oil group (p<0.0088). No significant side-effects were observed. The present results suggest that dietary supplementation with fish oil rich in the omega-3 polyunsaturated fatty acids eicosapentaenoic acid and docosahexaenoic acid is beneficial for children with bronchial asthma in a strictly controlled environment in terms of inhalant allergens and diet.

Identification of critical CpG sites for repression of L1 transcription by DNA methylation

L1 (LINE-1) is an interspersed non-LTR retrotransposon and several genetic defects caused by L1 transposition have been reported. L1 is thus considered as a potential mutagen. However, this potentially hazardous insertional event seems to be rare in spite of the presence of 3000 or more L1 elements of full or nearly full length in the human genome. Thus there must exist a mechanism(s) for repressing the expression of most, if not all, L1 elements. Some studies suggested that methylation plays a major role in the repression of L1 expression. However, no direct evidence has been presented and further study is required to draw a conclusion. We thus studied the effect of methylation on L1 transcription in vivo and in vitro. Transfection of plasmid which contained a L1 promoter linked to cat gene into HeLa cells showed that methylation did repress the L1 promoter activity. In vitro transcription studies using mutagenized templates indicated that methylation of the first seven CpGs in L1 promoter, particularly four CpGs at +52, +58, +61 and +70 was essential for the inhibition. These results suggest that there exists a mechanism to regulate the L1 transcription through the region-specific methylation.

Molecular cloning and characterization of a plasma membrane-associated sialidase specific for gangliosides

Gangliosides are plasma membrane components thought to play important roles in cell surface interactions, cell differentiation, and transmembrane signaling. A mammalian sialidase located in plasma membranes is unique in specifically hydrolyzing gangliosides, suggesting crucial roles in regulation of cell surface functions. Here we describe the cloning and expression of a cDNA for the ganglioside sialidase, isolated from a bovine brain cDNA library based on the amino acid sequence of the purified enzyme from bovine brain. This cDNA encodes a 428-amino acid protein containing a putative transmembrane domain and the three Asp boxes characteristic of sialidases and sharing 19-38% sequence identity with other sialidases. Northern blot and polymerase chain reaction analyses revealed a general distribution of the gene in mammalian species, including man, and the mouse. In COS-7 cells transiently expressing the sialidase, the activity was found to be 40-fold that of the control level with ganglioside substrates in the presence of Triton X-100, and the hydrolysis was almost specific to gangliosides other than GM1 and GM2, both alpha2-->3 and alpha2-->8 sialyl linkages being susceptible. The major subcellular localization of the expressed sialidase was assessed to be plasma membrane by Percoll density gradient centrifugation of cell homogenates and by immunofluorescence staining of the transfected COS-7 cells. Analysis of the membrane topology by protease protection assay suggested that this sialidase has a type I membrane orientation with its amino terminus facing to the extracytoplasmic side and lacking a signal sequence.

Assembly and activation of the phagocyte NADPH oxidase. Specific interaction of the N-terminal Src homology 3 domain of p47phox with p22phox is required for activation of the NADPH oxidase

The phagocyte NADPH oxidase is activated during phagocytosis to produce superoxide, a precursor of microbicidal oxidants. The activation involves assembly of membrane-integrated cytochrome b558 comprising gp91(phox) and p22(phox), two specialized cytosolic proteins (p47(phox) and p67(phox)), each containing two Src homology 3 (SH3) domains, and the small G protein Rac. In the present study, we show that the N-terminal SH3 domain of p47(phox) binds to the C-terminal cytoplasmic tail of p22(phox) with high affinity (KD = 0.34 microM). The binding is specific to this domain among several SH3 domains including the C-terminal one of p47(phox) and the two of p67(phox) and requires the Pro156-containing proline-rich sequence but not other putative SH3 domain-binding sites of p22(phox). Replacement of Trp193 by Arg in the N-terminal SH3 domain completely abrogates the association with p22(phox). A mutant p47(phox) with this substitution is incapable of supporting superoxide production under cell-free activation conditions. These findings provide direct evidence that the interaction between the N-terminal SH3 domain of p47(phox) and the proline-rich region of p22(phox) is essential for activation of the NADPH oxidase.

Single-beat estimation of the slope of the end-systolic pressure-volume relation in the human left ventricle

This study assessed a new method of estimating the slope (Ees) of the end-systolic pressure-volume relation (ESPVR) from a single beat of the human heart. Left ventricular pressure was recorded with a high-fidelity micromanometer in patients with heart disease during left ventriculography. Peak isovolumic pressure at the end-disastolic volume was estimated by a curve-fitting technique from an isovolumic left ventricular pressure curve. The ESPVR line was drawn from the estimated peak isovolumic pressure-volume point tangential to the left upper corner of the pressure-volume loop. The slope of this estimated ESPVR line from single-beat analysis was compared with the slope of the ESPVR line obtained from three pressure-volume loops in 16 patients given angiotensin II or nitroglycerin infusion. The estimated Ees was 5.0 +/- 2.2 mm Hg/ml/m2, and the conventional Ees was 4.9 +/- 2.7 mm Hg/ml/m2. The estimated Ees showed a positive correlation with the conventional Ees (r = 0.91, p less than 0.001, SEE = 1.2 mm Hg/ml/m2). In the other 13 patients, after dobutamine infusion (5 micrograms/kg/min i.v.) the estimated Ees increased significantly from 5.6 +/- 1.4 to 7.4 +/- 2.0 mm Hg/ml/m2 (p less than 0.01). Thus, the estimated Ees approximated the conventional Ees and was sensitive to a positive inotropic intervention. We conclude that this single-beat analysis method facilitates assessment of the beat-by-beat ESPVR of the human heart.

Bovine lactoferrin and lactoferricin, a peptide derived from bovine lactoferrin, inhibit tumor metastasis in mice

We investigated the effect of a bovine milk protein, lactoferrin (LF-B), and a pepsin-generated peptide of LF-B, lactoferricin (Lfcin-B), on inhibition of tumor metastasis produced by highly metastatic murine tumor cells, B16-BL6 melanoma and L5178Y-ML25 lymphoma cells, using experimental and spontaneous metastasis models in syngeneic mice. The subcutaneous (s.c.) administration of bovine apo-lactoferrin (apo-LF-B, 1 mg/mouse) and Lfcin-B (0.5 mg/mouse) 1 day after tumor inoculation significantly inhibited liver and lung metastasis of L5178Y-ML25 cells. However, human apolactoferrin (apo-LF-H) and bovine holo-lactoferrin (holo-LF-B) at the dose of 1 mg/mouse failed to inhibit tumor metastasis of L5178Y-ML25 cells. Similarly, the s.c. administration of apo-LF-B as well as Lfcin-B, but not apo-LF-H and holo-LF-B, 1 day after tumor inoculation resulted in significant inhibition of lung metastasis of B16-BL6 cells in an experimental metastasis model. Furthermore, in in vivo analysis for tumor-induced angiogenesis, both apo-LF-B and Lfcin-B inhibited the number of tumor-induced blood vessels and suppressed tumor growth on day 8 after tumor inoculation. However, in a long-term analysis of tumor growth for up to 21 days after tumor inoculation, single administration of apo-LF-B significantly suppressed the growth of B16-BL6 cells throughout the examination period, whereas Lfcin-B showed inhibitory activity only during the early period (8 days). In spontaneous metastasis of B16-BL6 melanoma cells, multiple administration of both apo-LF-B and Lfcin-B into tumor-bearing mice significantly inhibited lung metastasis produced by B16-BL6 cells, though only apo-LF-B exhibited an inhibitory effect on tumor growth at the time of primary tumor amputation (on day 21) after tumor inoculation. These results suggest that apo-LF-B and Lfcin-B inhibit tumor metastasis through different mechanisms, and that the inhibitory activity of LF-B on tumor metastasis may be related to iron (Fe3+)-saturation.

Cytokine regulation of chemokine (IL-8, MCP-1, and RANTES) gene expression in human pancreatic periacinar myofibroblasts

BACKGROUND & AIMS

We have previously isolated and characterized human pancreatic periacinar myofibroblasts. In this study, to define the role of these cells in the pathogenesis of acute pancreatitis, we investigated chemokine expression in them.

METHODS

Secretion of chemokines (interleukin [IL]-8, monocyte chemoattractant protein [MCP]-1, RANTES, and MIP [macrophage inflammatory protein]-1alpha) was evaluated by ELISA, Northern blotting, and nuclear run-on assays. The activation of NF-kappaB and NF-IL6 was assessed by an electrophoretic gel mobility shift assay.

RESULTS

IL-8 and MCP-1 secretion was rapidly induced by both IL-1beta and tumor necrosis factor (TNF)-alpha. RANTES secretion was induced more slowly and was induced mainly by TNF-alpha. However, MIP-1alpha secretion was not induced by any stimuli. These responses were also observed at the messenger RNA level, and they were accompanied by an increase in transcriptional rate. The increase in transcriptional activation of chemokine genes correlated with the NF-kappaB and NF-IL6 activation. Furthermore, a blockade of NF-kappaB activation by PDTC and TPCK markedly reduced the IL-1beta- or TNF-alpha-induced chemokine gene expression.

CONCLUSIONS

Chemokine secretion is differentially regulated in pancreatic periacinar myofibroblasts, suggesting a role for these cells in mediating the infiltration and accumulation of inflammatory cells in the pancreas.

Earlier surveillance colonoscopy programme improves survival in patients with ulcerative colitis associated colorectal cancer: results of a 23-year surveillance programme in the Japanese population

Patients with long-standing ulcerative colitis (UC) are known to have an increased risk for the development of colorectal cancer (CRC). The aim of this study was to clarify the cumulative risk for the development of dysplasia or invasive cancer and the effectiveness of surveillance colonoscopy in the Japanese population. A total of 217 patients received a total of 1027 surveillance colonoscopies between January 1979 and December 2001 at the University of Tokyo hospital. Patients with invasive cancer found in the surveillance group were compared to those referred to our hospital from the other hospitals without surveillance colonoscopy. Surveillance colonoscopy confirmed 15 patients with definite dysplasia. Of these, five were proved to have invasive cancer in the resected specimens. The cumulative risk for the development of invasive cancer at 10, 20, and 30 years was 0.5, 4.1, and 6.1%, respectively, while that for the development of definite dysplasia at 10, 20, and 30 years was 3.1, 10.0, and 15.6%, respectively. All the patients with invasive cancer in the surveillance group remained alive, while three out of four patients in the nonsurveillance group died. Our surveillance programme is useful for detecting UC-associated CRC, and survival may be improved by surveillance colonoscopy.

Core-binding factor alpha 1 (Cbfa1) induces osteoblastic differentiation of C2C12 cells without interactions with Smad1 and Smad5

Core-binding factor alpha(1) (Cbfa1) is an essential transcription factor for osteoblastic differentiation and osteogenesis. Bone morphogenetic protein (BMP) is also a powerful inducer of differentiation of pluripotent mesenchymal cells to osteoblast lineage and bone formation. Recent studies suggest that Cbfa1 plays a critical role during BMP-induced osteoblastic differentiation through association with cytoplasmic BMP signaling molecules, Smads. However, other studies have suggested that Cbfa1 may exhibit its osteogenic function without interaction with Smads. Therefore, it remains unclear whether association with Smad is essential for Cbfa1 function. In this study we examine the effects of Cbfa1 on osteoblastic differentiation in the presence or absence of interactions with Smad1 or Smad5 using C2C12 undifferentiated mesenchymal cells. Cbfa1 expression was induced upon stimulation with BMP-2 in C2C12 cells. Introduction of Cbfa1 into C2C12 cells induced osteoblastic differentiation and promoted transactivation of osteocalcin gene promoter without forming the complex with Smad1 or Smad5. Furthermore, in C2C12 cells in which the association of Cbfa1 with Smad1/Smad5 was prevented by the overexpression of the natural antagonist, Smad6, Cbfa1 still induced osteoblastic differentiation and transactivated osteocalcin gene promoter, regardless of BMP-2 stimulation. These results suggest that the interactions with Smad1 or Smad5 are not essential for Cbfa1 to demonstrate its osteogenic actions. However, interactions with Smad1/Smad5 enhance these osteogenic actions of Cbfa1. Of note, BMP-2-induced or Smad-induced osteoblastic differentiation was inhibited by dominant-negative Cbfa1, suggesting that the function of Cbfa1 is critical for BMP-2-induced osteoblastic differentiation. Our results suggest that Cbfa1 is essential and also sufficient to induce osteoblastic differentiation in undifferentiated mesenchymal cells, and establishment of an association with Smad1/Smad5 enhances the osteogenic actions of Cbfa1. On the other hand, Cbfa1 expression requires the activation of Smad1/Smad5 by BMP-2.

Isolation, phenotyping, and functional analysis of lymphocytes from human liver

The isolation of mononuclear cells from human liver tissues was achieved by a simple method consisting of enzymatic and mechanical dissociation, density gradient centrifugation, and adherence to plastic. The method was optimized to obtain a nearly complete recovery of different lymphoid subpopulations. The mononuclear cells recovered from "normal" liver tissues consisted of 33 +/- 9% (mean +/- SD) small lymphocytes, 44 +/- 6% large granular lymphocytes, 9 +/- 2% monocytes/macrophages, 9 +/- 3% granulocytes, and 5 +/- 2% other cells as determined by microscopic analysis of May-Grünwald-Giemsa-stained cytocentrifuge smears. Phenotypic analysis of the liver-infiltrating lymphocytes (LIL) by two-color flow cytometry showed that CD3-CD56+ NK cells represented 43 +/- 6% (mean +/- SD), CD3+CD56- T cells, 30 +/- 9%, and CD19+ B cells 3 +/- 1%. The predominant phenotype of the liver-infiltrating NK cells was CD3-CD56+CD16- in contrast to that of circulating NK cells, which are largely CD3-CD56+CD16+. The alpha/beta TCR+ T cells were 42 +/- 14% and gamma/delta T cells were infrequent (4 +/- 4%). The proportions of the three major lymphoid populations (T, NK, and B cells) recovered from liver tissues of 10 patients with different liver diseases were altered. Tissue sections from the same specimens were stained by the immunoperoxidase method to compare the in situ cellular composition with that determined by flow cytometry. LIL recovered from normal (control) and virally infected (non-A, non-B hepatitis) liver tissues had high NK activity (up to 1,000 LU/10(7) cells) as measured against K-562 targets in 4-hr 51Cr-release assays. NK activity was significantly lower (P less than 0.05) in LIL recovered from other liver diseases. LIL had spontaneous cytotoxicity against NK-resistant Daudi targets which was significantly higher (P less than 0.05) in control and virally infected than in other liver tissues. Our results indicated that human LIL recovered from normal and diseased liver tissues contained a high proportion of functionally active NK cells and that NK and lymphokine-activated killer activities but not the percentages of CD56+ cells were decreased in end-stage primary biliary cirrhosis and primary sclerosing cholangitis. In contrast, the proportions of NK cells and NK activity remain high in non-A, non-B hepatitis.

In vitro and in vivo antifungal activities of ER-30346, a novel oral triazole with a broad antifungal spectrum

ER-30346 is a novel oral triazole with a broad spectrum of potent activity against a wide range of fungi. ER-30346, with MICs at which 90% of the strains tested are inhibited (MIC90s) ranging from 0.025 to 0.78 microgram/ml, was 4 to 32 times more active than itraconazole, fluconazole, and amphotericin B against Candida albicans, Candida parapsilosis, and Candida glabrata. Against Candida tropicalis, ER-30346, with an MIC90 of 12.5 micrograms/ml, was 2 to > 8 times more active than itraconazole and fluconazole, but was 16 times less active than amphotericin B. ER-30346 (MIC90, 0.78 microgram/ml) was four to eight times more active than fluconazole and amphotericin B and had activity comparable to that of itraconazole against Trichosporon beigelli. The MIC90s of ER-30346 were 0.10 microgram/ml for Cryptococcus neoformans and 0.39 microgram/ml for Aspergillus fumigatus. ER-30346 was 2 to 8 times more active than itraconazole and amphotericin B and 32 to > 256 times more active than fluconazole. ER-30346 also showed good activity against dermatophytes, with MICs ranging from 0.05 to 0.39 microgram/ml, and its activity was comparable to or 2 to 16 times higher than those of itraconazole and amphotericin B and > 32 times higher than that of fluconazole. In vivo activity was evaluated with systemic infections in mice. Against systemic candidiasis and cryptococcosis, ER-30346 was comparable in efficacy to fluconazole and was more effective than itraconazole. Of the drugs tested, ER-30346 was the most effective drug against systemic aspergillosis. We studied the levels of ER-30346 in mouse plasma. The maximum concentration of drug in plasma and the area under the concentration-time curve for ER-30346 showed good linearity over a range of doses from 2 to 40 mg/kg of body weight.

Urinary excretion of aquaporin-2 water channel protein in human and rat

Previous studies by the authors demonstrated that the response of urinary aquaporin-2 (AQP2) excretion to dDAVP (deamino-8-D-arginine vasopressin) infusion is an index of vasopressin action on the kidney (N Engl J Med 332: 1540-1545, 1995). In the study presented here, the characteristics of urinary excretion of AQP2 were examined further. An RIA suitable for AQP2 in the urine was established. Relatively high concentrations of detergent and bovine serum albumin in the RIA buffer allowed analysis of urine samples with a wide range of concentrations and increased the sensitivity of the assay. AQP2 in the urine existed as a high molecular weight form of approximately 190 kD by HPLC analysis. The mean urinary AQP2 concentration corrected for creatinine in spot urine samples of healthy subjects who voided in the morning was 1081 +/- 699 fmol/mg creatinine (mean +/- SD, n = 208). The amount of daily excretion of AQP2 in the urine was the same in men and women. Urinary AQP2 content was not affected by age of the subjects and showed a positive correlation with urine osmolality. Finally, the fraction of AQP2 excreted in the urine compared with whole kidney content was determined in the rat. Approximately 3% of AQP2 in the kidney was excreted daily, and this fraction did not change when rats were dehydrated for 3 d. These data demonstrate the necessity of establishing well-designed protocols to use urinary AQP2 as a marker of AVP action.

Development of fulminant hepatitis B (precore variant mutant type) after the discontinuation of low-dose methotrexate therapy in a rheumatoid arthritis patient

A 75-year-old female rheumatoid arthritis patient who was positive for hepatitis B surface antigen and for antibodies to hepatitis Be antigen showed liver dysfunction, and therefore methotrexate (MTX) therapy was discontinued. Her drug lymphocyte stimulation test indicated positivity for MTX. Her liver dysfunction improved briefly, but she developed fulminant hepatitis with elevated levels of hepatitis B virus (HBV)/DNA polymerase and subsequently died. HBV/DNA analysis performed with polymerase chain reaction-mutation site-specific assay revealed that the fulminant hepatitis was caused by a precore mutant virus. Sudden reactivation of the immune system by discontinuation of MTX may have led to the attack on infected cells. Even when hepatitis Be antibodies are present, MTX should not be used in patients who have chronic infection with HBV.

Patients with extraintestinal manifestations have a higher risk of developing pouchitis in ulcerative colitis: multivariate analysis

BACKGROUND

Restorative proctocolectomy and ileal pouch-anal anastomosis (IPAA) have been the surgical treatments of choice for ulcerative colitis (UC). However, the IPAA is sometimes complicated with pouchitis. Furthermore, the cumulative risk and risk factors for developing pouchitis in patients with UC undergoing IPAA have not been reported in any Asian population. The aim of our study is to clarify the cumulative risk and risk factors for developing pouchitis in Japanese patients with UC undergoing IPAA.

METHODS

Fifty-eight patients with UC undergoing IPAA were retrospectively evaluated for the presence of pouchitis, gender, age of onset, history of smoking, presence of extraintestinal manifestations (EIMs) and type of operation. The diagnosis of pouchitis was based on the pouchitis disease activity index. The cumulative risk and risk factors for developing pouchitis were assessed.

RESULTS

The cumulative risks for developing pouchitis at 1 and 5 years were 9.0% and 14.4%, respectively. The estimated risks of pouchitis at 5 years was 48.1% in patients with EIMs and 4.6% in those without. Both univariate and multivariate analyses revealed that the presence of EIMs is a significant risk factor (hazard ratio 16.85, 95% confidence interval 3.12-91.00; P=0.001).

CONCLUSIONS

The presence of EIMs is a significant risk factor for the development of pouchitis in Japanese patients with UC undergoing IPAA.

Rapid diagnosis of adenoviral conjunctivitis by PCR and restriction fragment length polymorphism analysis

To detect and identify adenovirus (Ad), we used a combination of PCR and restriction fragment length polymorphism (RFLP) analysis. Nested PCR with two primer sets that hybridize to the conserved region for hexon proteins of 14 prototypes of Ad, Ad serotype 1 (Ad1) to Ad8, -11, -14, -19, -37, -40, and -41, amplified a 956-bp DNA fragment. The amplified fragments from the 14 prototypes were completely differentiated with a combination of three restriction endonucleases, EcoT14I, HaeIII, and HintI. We applied this new method for 127 samples of conjunctival scrapings from patients with conjunctivitis and compared the results with those obtained with the combination of culture isolation and a neutralization test (NT). PCR gave a positive result in 69 of 127 cases (54.3%), while only 61 of the 127 samples (48.0%) tested positive by culture isolation. Compared with isolation, the PCR method had a sensitivity of 100% (61 of 61). Positive PCR samples were further classified as Ad37 (59.5%), -3(31.9%), -11 (4.3%), -8 (2.9%), and -4 (1.4%) by PCR-RFLP analysis. Of eight samples that were PCR positive and culture isolation negative, six were Ad37 and two were Ad8 by PCR-RFLP analysis. These differentiations of isolation-positive samples were identical to the results obtained by the NT. It took only 3 days to detect and identify Ad by PCR-RFLP analysis, whereas it took at least 3 weeks by culture isolation and NT. Our newly developed method of detecting and typing human Ad by PCR-RFLP analysis is more sensitive, accurate, and rapid than the conventional method of culture isolation and an NT.

A crucial role of plasma membrane-associated sialidase in the survival of human cancer cells

Human plasma membrane-associated sialidase (NEU3), a key enzyme for ganglioside degradation, is markedly upregulated in human cancers, leading to apoptosis suppression. To define molecular mechanisms and the possible target for NEU3, its encoding gene was silenced by small interference RNA (siRNA) or overexpressed in human cells. NEU3 siRNA-induced apoptosis with no special stimuli in HeLa cells, accompanied with decreased Bcl-xL and increased mda7 and GM3 synthase mRNA levels, whereas overexpression resulted in the opposite. Carcinoma HT-29 and MCF-7 cells appeared to be similarly affected, but normal cell lines demonstrated no significant changes. NEU3 siRNA was found to inhibit and NEU3 overexpression to stimulate Ras activation with consequent influence on extracellular signal-regulated kinases and Akt. Ras activation by NEU3 was abrogated by PP2 (src inhibitor) or AG1478 (epidermal growth factor receptor (EGFR) inhibitor), and NEU3 actually enhanced EGF-stimulated tyrosine-phosphorylation of EGFR, suggesting that the upstream targets might be tyrosine kinases including src and EGFR, and the subsequent stimulation of Ras cascade leads to the inhibition of cell apoptosis. Glycolipid changes observed seemed to be one of the causes of the cell effects. NEU3 may thus be an essential gene for cancer cell survival and siRNAs targeting this protein could have utility for gene-based therapy of human cancers.

Plasma brain natriuretic peptide as a novel therapeutic indicator in idiopathic dilated cardiomyopathy during beta-blocker therapy: a potential of hormone-guided treatment

BACKGROUND

Plasma brain natriuretic peptide (BNP) is a sensitive and specific marker of left ventricular (LV) function. In the treatment of heart failure, especially in idiopathic dilated cardiomyopathy (IDC), beta-blocker (BB) therapy has been established as a powerful strategy. The purpose of this study was to analyze relationships between changes in BNP level and LV function during BB therapy in patients with IDC.

METHODS

In 30 patients with IDC who had already received conventional therapy, measurement for plasma BNP and norepinephrine levels and echocardiographic indices were evaluated before and 2 and 6 months after carvedilol in 21 patients and at baseline and after 6 months in 9 patients who did not receive carvedilol.

RESULTS

After 6 months carvedilol treatment significantly improved LV end-diastolic dimension (LVEDD) (65 +/- 8 to 61 +/- 8 mm) and LV ejection fraction (LVEF) (34% +/- 13% to 43% +/- 12%) with intergroup differences; it significantly decreased BNP (127 +/- 113 to 69 +/- 92 pg/mL) with no intergroup difference; however, it did not decrease norepinephrine. BNP correlated strongly with LVEDD, LVEF, and LV mass index in carvedilol-treated patients. The degree of change in BNP correlated with that in LVEDD or LVEF 6 months after carvedilol. All 14 patients with decreased or unchanged BNP levels showed an increase in LVEF, and 4 of 7 with a rise in BNP had decreased or unchanged LVEF. According to receiver operating characteristic analysis, the optimal BNP levels for detecting LVEF <35% before and after carvedilol were 75.5 and 69 pg/mL, respectively.

CONCLUSION

Plasma BNP levels may accurately reflect alteration in LV function and structure and can be used as a therapeutic indicator for risk stratification in patients with IDC during BB therapy.

The PC motif: a novel and evolutionarily conserved sequence involved in interaction between p40phox and p67phox, SH3 domain-containing cytosolic factors of the phagocyte NADPH oxidase

The superoxide-generating NADPH oxidase, dormant in resting phagocytes, is activated during phagocytosis following assembly of the membrane-integrated protein cytochrome b558 and cytosolic factors. Among the latter are the three proteins containing Src homology 3 (SH3) domains, p67phox, p47phox and p40phox. While the first two factors are indispensable for the activity, p40phox is tightly associated with p67phox in resting cells and is suggested to have some modulatory role. Here we describe a systematic analysis of the interaction between p40phox and p67phox using the yeast two-hybrid system and in vitro binding assays with recombinant proteins. Both methods unequivocally showed that the minimum requirements for stable interaction are the C-terminal region of p40phox and the region between the two SH3 domains of p67phox. This interaction is maintained even in the presence of anionic amphiphiles used for the activation of the NADPH oxidase, raising a possibility that it mediates constitutive association of the two factors in both resting and activated cells. The C-terminal region of p40phox responsible for the interaction contains a characteristic stretch of amino acids designated as the PC motif, that also exists in other signal-transducing proteins from yeast to human. Intensive site-directed mutagenesis to the motif in p40phox revealed that it plays a critical role in the binding to p67phox. Thus the PC motif appears to represent a novel module for protein-protein interaction used in a variety of signaling pathways.

Comparison of Ehrlichia muris strains isolated from wild mice and ticks and serologic survey of humans and animals with E. muris as antigen

In metropolitan Tokyo, the Ehrlichia muris seropositivity rate of 24 wild mice was 63% in Hinohara Village, but in the surrounding areas, it was 0 to 5%. This finding suggests that the reservoir of E. muris is focal. Among the 15 seropositive mice, ehrlichiae were isolated from 9 Apodemus speciosus mice and 1 A. argenteus mouse, respectively. Five ehrlichial isolates were obtained from 10 ticks (Haemaphysalis flava) collected in Asuke Town, Aichi Prefecture, where the E. muris type strain had been isolated. These new isolates were compared with the E. muris type strain. The mouse virulence and ultrastructure of the new isolates were similar to those of the type strain, and all of them were cross-reactive with each other, as well as with the type strain, by indirect immunofluorescent-antibody test. The levels of similarity of the base sequences of the 16S rRNA gene of one of the A. speciosus isolates and one of the tick isolates to that of the E. muris type strain were 99.79 and 99.93%, respectively. We suggest that all of these isolates are E. muris; that E. muris is not limited to Eothenomys kageus but infects other species of mice; and that E. muris is present at locations other than Aichi Prefecture. It appears that H. flava is a potential vector of E. muris. Twenty (1%) of 1803 humans from metropolitan Tokyo were found to be seropositive for E. muris antibodies. A serological survey revealed that exposure to E. muris or organisms antigenically cross-reactive to E. muris occurred among dogs, wild mice, monkeys, bears, deer, and wild boars in Gifu Prefecture, nearby prefectures, and Nagoya City, central Japan. However, human beings and Rattus norvegicus rats in this area were seronegative. These results indicate broader geographic distribution of and human and animal species exposure to E. muris or related Ehrlichia spp. in Japan.

Counter-regulatory effect of sodium butyrate on tumour necrosis factor-alpha (TNF-alpha)-induced complement C3 and factor B biosynthesis in human intestinal epithelial cells

The various biological activities of butyrate have been well documented. In this study, we tested the effects of butyrate on TNF-alpha-induced complement C3 and factor B biosynthesis in human intestinal epithelial cells. The biosynthesis of C3, factor B and IL-8 was evaluated at the protein and mRNA levels. To evaluate transcriptional activation, the nuclear run-on assay was performed. The transcription factor-DNA binding activity was assessed by an electrophoretic gel mobility shift assay (EMSA). In the intestinal epithelial cell lines HT-29, T84 and Caco-2, sodium butyrate enhanced TNF-alpha-induced C3 secretion, but suppressed TNF-alpha-induced factor B and IL-8 secretion. Nuclear run-on assay revealed that transcriptional regulatory mechanisms are involved in the effects of sodium butyrate. The EMSAs indicated that sodium butyrate suppressed TNF-alpha-induced nuclear factor (NF)-kappaB- and activation protein (AP)-1-DNA binding activity, but enhanced TNF-alpha-induced activation of CCAAT/enhancer-binding protein (C/EBP)beta (NF-IL-6)-DNA binding activity. Sodium butyrate induced a counter-regulatory effect on TNF-alpha-induced C3 and factor B biosynthesis in human intestinal epithelial cells. Butyrate action has been discussed with its activity to induce histone hyperacetylation, but its counter-regulatory effect on complement biosynthesis may be closely associated with the modulation of transcription factor activation.