Circumferential Stenosis of the Second Part of the Duodenum Caused by Eosinophilic Gastroenteritis

Isolated eosinophilic gastroenteritis (EGE) of the second part of the duodenum is rare. We herein report a case of EGE limited to the second part of the duodenum that caused circumferential stenosis due to massive wall thickening. A boring biopsy was useful to verify the accumulation of eosinophils. Induction of remission by prednisolone was accompanied by a marked reduction in the mRNA expression of interleukin-6, C-C motif chemokine ligand 17 (CCL17), and CCL26 without any reduction in prototypical EGE-associated T helper type 2 cytokines (IL-5, IL-13). Thus, the enhanced expression of IL-6, CCL17, and CCL26 might be involved in the development of EGE in this case.

Analyses of cytokine gene expression and fecal microbiota in a patient with Cronkhite-Canada syndrome successfully treated with prednisolone

Although prednisolone treatment is effective in Cronkhite-Canada syndrome (CCS), its mechanisms of action are poorly understood. We performed analyses of cytokine expression and fecal microbiota in a patient with the concurrent occurrence of CCS and rectal cancer, in whom regression of polyposis was achieved by prednisolone. Regression of CCS polyps was accompanied by downregulation of proinflammatory cytokine expression and alterations in microbiota composition; a decrease in Bacteroides fragilis and Peptostreptococcus anaerobius with the promotion of inflammation. We could not completely exclude the possibility that alterations in fecal microbiota composition might be influenced by the presence of advanced cancer. However, this case suggests that the administration of PSL might lead to the regression of CCS polyps through alterations in gut microbiota composition and suppression of proinflammatory cytokine responses.

Crosstalk between NOD2 and TLR2 suppresses the development of TLR2-mediated experimental colitis

Nucleotide-binding oligomerization domain 2 (NOD2) is an intracellular sensor for muramyl dipeptide (MDP), a degradation product of bacterial cell wall peptidoglycan (PGN). PGN stimulates cell-surface Toll-like receptor 2 (TLR2) independently of NOD2, indicating the presence of crosstalk between extracellular TLR2 and intracellular NOD2 upon exposure to PGN. NOD2-deficient mice were sensitive, while TLR2-deficient mice were resistant to experimental colitis induced by intrarectal administration of PGN. Severe colitis in NOD2-deficient mice was accompanied by increased expression of nuclear factor-kappa B-dependent cytokines and decreased expression of autophagy-related 16-like 1 (ATG16L1). MDP activation of NOD2 enhanced autophagy mediated by TLR2 in human dendritic cells. mRNA expression of TLR2 tended to be higher in the colonic mucosa of patients with active ulcerative colitis compared to that of those in remission. Induction of remission was associated with increased mRNA expression of ATG16L1 in both ulcerative colitis and Crohn's disease patients. Conversely, mRNA expression of receptor-interacting serine/threonine-protein kinase 2 was higher in the inflammatory colonic mucosa of patients with active disease than in the non-inflamed mucosa of patients in remission, in both ulcerative colitis and Crohn's disease. These findings highlight the role of NOD2-TLR2 crosstalk in the immunopathogenesis of colitis.

Cytokine and chemokine profiles in ulcerative colitis relapse after coronavirus disease 2019 vaccination

Coronavirus disease 2019 (COVID-19) vaccines are highly effective; however, vaccine-related adverse events, including autoimmunity, have been reported. Case reports describing relapse or new-onset of ulcerative colitis (UC) after COVID-19 mRNA vaccination are available. However, the molecular mechanisms underlying the development of colonic inflammation associated with COVID-19 mRNA vaccination are poorly understood. Furthermore, it is unclear whether the relapse of UC after COVID-19 vaccination is driven by unique cytokine responses that differ from those of UC not associated with vaccination. mRNAs derived from COVID-19 vaccines are potent inducers of type I IFN response. We encountered three cases of UC relapse after COVID-19 vaccination. mRNA expressions of IFN-α, IFN-β, IL-1β, and IL-12/23p40 showed higher tendency in the colonic mucosa of patients with UC associated with vaccination compared with those not associated with vaccination. In contrast, the expressions of C-X-C motif chemokine ligand 9 (CXCL9) and CXCL10 were comparable. Immunofluorescence analyses also showed higher expression of IFN-α in the colonic mucosa of patients with UC associated with COVID-19 vaccination than in those not associated with vaccination. Taken together, these data suggest that the colonic mucosa of patients with UC who relapsed after COVID-19 vaccination was characterized by enhanced type I IFN responses.

Visualization of Gastrointestinal Bezoar Movement Causing and Releasing Small Bowel Obstruction on Computed Tomography in a Patient With Diabetes Mellitus

Although delayed gastric emptying promotes gastrointestinal bezoar formation in patients with diabetes mellitus (DM), the association between movement of gastrointestinal bezoars and glycemic status remains unclear. We report a case of small bowel obstruction (SBO) caused by impaction of the migrated gastric bezoar into the small bowel in a patient with DM. Correction of hyperglycemia and lactic acidosis led to normalization of gastrointestinal motility, followed by expulsion of the impacted bezoar and resolution of SBO. This case suggests a link between hyperglycemia, metabolic acidosis, and gastrointestinal motility based on visualization of gastrointestinal bezoar movement in the gastrointestinal tract using computed tomography.

Oral administration of ovalbumin protects mice from concanavalin A-induced hepatitis through suppression of interferon-gamma responses

The liver is a tolerogenic organ that exhibits hypo-responsiveness to antigens circulating in the portal vein. Antigens that are orally administered at high doses reach the liver. In our previous study, we demonstrated that administering ovalbumin (OVA) orally at high doses generates unique CD4+ T cells and tolerogenic dendritic cells, both of which can suppress T helper type 1 (Th1) responses, in the livers of two groups of mice: DO11.10 mice with transgenic CD4+ T cell receptors for OVA and BALB/c mice that received OVA-specific CD4+ T cells through adoptive transfer. This study aimed to investigate whether oral administration of OVA at high doses inhibits the development of hepatitis in the presence of OVA-specific CD4+ T cells. Oral administration of OVA at high doses inhibited the development of OVA-specific and concanavalin A (Con A)-induced hepatitis in DO11.10 mice, and these effects were associated with the downregulation of Th1 responses. Furthermore, the adoptive transfer of CD4+ T cells from the liver of OVA-fed DO11.10 mice inhibited the development of Con A-induced hepatitis in recipient BALB/c mice through the downregulation of Th1 responses. Finally, oral administration of OVA at high doses inhibited the development of Con A-induced hepatitis in BALB/c mice bearing naïve OVA-specific CD4+ T cells. These results suggest that the oral administration of antigens at high doses suppresses Th1-mediated hepatitis in an antigen-non-specific manner in the presence of antigen-specific CD4+ T cells.

Regulation of type I IFN responses by deubiquitinating enzyme A in inflammatory bowel diseases

The development of Inflammatory bowel disease (IBD) is driven by excessive production of pro-inflammatory cytokines including TNF-α, IL-12, and IL-23. This notion is supported by the remarkable clinical success of biologics targeting these cytokines. Recognition of cell wall components derived from intestinal bacteria by Toll-like receptors (TLRs) induces the production of these pro-inflammatory cytokines by macrophages and dendritic cells in human IBD and experimental colitis model. Although sensing of bacterial nucleic acids by endosomal TLRs, specifically TLR3, TLR7, and TLR9 leads to robust production of type I IFNs, it remains debatable whether TLR-mediated type I IFN responses are pathogenic or protective in IBD patients. Additionally, recent studies identified deubiquitinating enzyme A (DUBA) as a novel negative regulator of TLR-mediated type I IFN responses. In light of these observations and their potential applications, in this review, we summarize recent findings on the roles of type I IFN responses and DUBA-mediated negative regulation of these responses in human IBD and experimental colitis model.

Ulcerative Colitis-associated Spondyloarthritis Successfully Treated with Infliximab in the Absence of Enhanced TNF-α Responses

Although concurrent occurrence of spondyloarthritis (SpA) and ulcerative colitis (UC) is sometimes seen, the profiles of cytokines have been poorly understood in UC-associated SpA. We herein report a case of UC-associated SpA successfully treated with infliximab (IFX). Profiles of cytokines in the serum and colonic mucosa were characterized by an enhanced expression of IL-6 but not tumor necrosis factor (TNF)-α. Successful induction of remission by IFX was associated with the downregulation of IL-6 expression but no significant alteration in TNF-α expression. These findings suggest that some cases of UC-associated SpA might be driven by IL-6, and IFX might be effective in cases lacking enhanced TNF-α responses.

Activation of nucleotide-binding oligomerization domain 2 by muramyl dipeptide negatively regulates Toll-like receptor 9-mediated colonic inflammation through the induction of deubiquitinating enzyme A expression

Mutations in nucleotide-binding oligomerization domain 2 (NOD2) are associated with Crohn's disease (CD). Although NOD2 activation contributes to the maintenance of intestinal homeostasis through the negative regulation of pro-inflammatory cytokine responses mediated by Toll-like receptors (TLRs), the effects of NOD2 activation on interferon (IFN)-α responses induced by TLR9 have been poorly defined. To explore the cross-talk between NOD2 and TLR9, human monocytes or dendritic cells (DCs) were stimulated with NOD2 and/or TLR9 ligands to measure IFN-α production. The severity of dextran sodium sulfate (DSS)-induced colitis was compared in mice treated with NOD2 and/or TLR9 ligands. Expression of IFN-α and IFN-stimulated genes (ISGs) was examined in the colonic mucosa of patients with inflammatory bowel disease (IBD). NOD2 activation reduced TLR9-induced IFN-α production by monocytes and DCs in a deubiquitinating enzyme A (DUBA)-dependent manner. Activation of DUBA induced by the co-stimulation of TLR9 and NOD2 inhibited Lys63-linked polyubiquitination of TRAF3 and suppressed TLR9-mediated IFN-α production. NOD2 activation in hematopoietic cells protected mice from TLR9-induced exacerbation of DSS-induced colitis by down-regulating IFN-α responses and up-regulating DUBA expression. Colonic mucosa of patients with active and remitted IBD phases was characterized by the enhanced and reduced expression of ISGs, respectively. Expression levels of IFN-α and IL-6 positively correlated in the active colonic mucosa of patients with ulcerative colitis and CD, whereas DUBA expression inversely correlated with that of IFN-α in patients with CD. Collectively, these data suggest that DUBA-dependent negative effect of NOD2 on TLR9-mediated IFN-α responses contributes to the maintenance of intestinal homeostasis.

Successful initial tofacitinib treatment for acute severe ulcerative colitis with steroid resistance: a case series

Background

The standard therapy for acute severe ulcerative colitis (ASUC) is intravenous corticosteroids; however, 30% of ulcerative colitis (UC) patients do not recover with corticosteroids alone. Few studies have reported the efficacy and safety of tofacitinib for ASUC with steroid resistance. We report a case series of successful first-line treatment consisting of tofacitinib (20 mg/day) administered to ASUC patients with steroid resistance.

Methods

Patients diagnosed with ASUC at our institution between October 2018 and February 2020 were retrospectively evaluated. They were administered a high dose of tofacitinib (20 mg) after showing no response to steroid therapy in a dose of 1-1.5 mg/kg/day.

Results

Eight patients with ASUC, 4 (50%) men, median age 47.1 (range 19-65) years, were included. Four patients were newly diagnosed, and the median UC duration was 4 (range 0-20) years. Six of the 8 patients were able to avoid colectomy. One patient (patient 2) had no response; however, remission was achieved after switching from tofacitinib to infliximab. One patient (patient 6) with no response to tofacitinib underwent total colectomy. Only one patient (patient 4) experienced an adverse event, local herpes zoster, treated with acyclovir without tofacitinib discontinuation.

Conclusions

Clinical remission without serious adverse events can be achieved with high probability and colectomy can be avoided by first administering high-dose tofacitinib to steroid-resistant ASUC patients. Tofacitinib may be one of the first-line treatment options for steroid-resistant ASUC.

Alterations of autophagic and innate immune responses by the Crohn’s disease-associated ATG16L1 mutation

Crohn’s disease (CD) is driven by the loss of tolerance to intestinal microbiota and excessive production of pro-inflammatory cytokines. These pro-inflammatory cytokines are produced by macrophages and dendritic cells (DCs) upon sensing the intestinal microbiota by the pattern recognition receptors (PRRs). Impaired activation of PRR-mediated signaling pathways is associated with chronic gastrointestinal inflammation, as shown by the fact that loss-of-function mutations in the nucleotide-binding oligomerization domain 2 gene increase the risk of CD development. Autophagy is an intracellular degradation process, during which cytoplasmic nutrients and intracellular pathogens are digested. Given that impaired reaction to intestinal microbiota alters signaling pathways mediated by PRRs, it is likely that dysfunction of the autophagic machinery is involved in the development of CD. Indeed, the loss-of-function mutation T300A in the autophagy related 16 like 1 (ATG16L1) protein, a critical regulator of autophagy, increases susceptibility to CD. Recent studies have provided evidence that ATG16L1 is involved not only in autophagy, but also in PRR-mediated signaling pathways. ATG16L1 negatively regulates pro-inflammatory cytokine responses of macrophages and DCs after these cells sense the intestinal microbiota by PRRs. Here, we discuss the molecular mechanisms underlying the development of CD in the T300A ATG16L1 mutation by focusing on PRR-mediated signaling pathways.

Case Report: Regulatory T Cell-Independent Induction of Remission in a Patient With Collagenous Colitis

Collagenous colitis (CC), a prototypical microscopic colitis, is a chronic inflammatory disorder of the colon. The diagnosis of CC depends on the pathological examination. The colonic mucosa of patients with CC is characterized by the presence of a substantially thickened collagen band (>10μm) under the surface epithelium. In addition, intraepithelial and lamina propria lymphocytes are markedly increased in patients with CC. However, the roles played by the lymphocytes accumulating in the colonic mucosa of patients with CC are poorly defined. Recent studies indicate that T cells infiltrating the colonic mucosa of patients with CC are mainly represented by CD4⁺ T cells, CD8⁺ T cells, and forkhead box P3 (FOXP3)⁺ regulatory T cells (Tregs). Given that activation of CD4⁺/CD8⁺ T cells and FOXP3⁺ Tregs usually mediates pro-inflammatory and anti-inflammatory responses, respectively, alterations in the colonic numbers of these adaptive T cells might be related to the resolution of colitis in patients with CC. We determined alterations in the composition of colonic T cells by extensive immunohistochemical (IHC) analyses in a case of CC successfully treated with budesonide and metronidazole. Colonic lamina propria immune cells mainly comprised CD3⁺ T cells, CD4⁺ T cells, CD8⁺ T cells, CD68⁺ macrophages, and FOXP3⁺ Tregs, but not CD20⁺ B cells or myeloperoxidase (MPO)⁺ granulocytes in the active phase. During remission, the numbers of CD3⁺ T cells, CD4⁺ T cells, CD8⁺ T cells, and CD68⁺ macrophages did not change significantly in the colonic lamina propria, whereas FOXP3⁺ Tregs were markedly decreased, suggesting that induction of remission was achieved in a Treg-independent manner. Thus, our study indicates that accumulation of FOXP3⁺ Tregs in the colonic mucosa of patients with CC might be a counter-regulatory mechanism reflecting persistent inflammation and that induction of remission might be achieved without activation of Tregs.

A case with Crohn's disease-associated spondyloarthritis exhibiting enhanced pro-inflammatory cytokine responses to Toll-like receptor ligands

BACKGROUND

Despite the high incidence of spondyloarthritis (SpA) as an extra-intestinal manifestation of Crohn's disease (CD), the immunopathogenesis of CD-associated SpA remains largely unknown.

OBJECTIVE

We tried to explore molecular mechanisms accounting for the development of CD-associated SpA in a patient successfully treated with infliximab.

METHODS

Peripheral blood mononuclear cells (PBMCs) before infliximab treatment were stimulated with Toll-like receptor (TLR) ligands to measure pro-inflammatory cytokine responses. Endoscopic biopsy samples before and after infliximab treatment were subjected to quantitative polymerase chain reaction.

RESULTS

PBMCs from this CD-associated SpA patient exhibited higher production of pro-inflammatory cytokines upon stimulation with TLR ligands than PBMCs from healthy controls. Induction of remission by infliximab was associated with the downregulation of pro-inflammatory cytokine responses in the small intestinal mucosa, which is continually exposed to TLR ligands.

CONCLUSIONS

Excessive pro-inflammatory cytokine responses to TLR ligands might underlie the immunopathogenesis of CD-associated SpA.

RIPK2 as a New Therapeutic Target in Inflammatory Bowel Diseases

Inflammatory bowel diseases (IBDs) are becoming more frequent worldwide. A significant fraction of patients with IBD are refractory to various types of therapeutic biologics and small molecules. Therefore, identification of novel therapeutic targets in IBD is required. Receptor-interacting serine/threonine kinase 2 (RIPK2), also known as receptor-interacting protein 2 (RIP2), is a downstream signaling molecule for nucleotide-binding oligomerization domain 1 (NOD1), NOD2, and Toll-like receptors (TLRs). RIPK2 is expressed in antigen-presenting cells, such as dendritic cells and macrophages. Recognition of microbe-associated molecular patterns by NOD1, NOD2, and TLRs leads to the interaction between RIPK2 and these innate immune receptors, followed by the release of pro-inflammatory cytokines such as TNF-α, IL-6, and IL-12/23p40 through the activation of nuclear factor kappa B and mitogen-activated protein kinases. Thus, activation of RIPK2 plays a critical role in host defense against microbial infections. Recent experimental and clinical studies have provided evidence that activation of RIPK2 is involved in the development of autoimmune diseases, especially IBDs. In addition, the colonic mucosa of patients with IBD exhibits enhanced expression of RIPK2 and associated signaling molecules. Furthermore, the blockage of RIPK2 activation ameliorates the development of experimental murine colitis. Thus, activation of RIPK2 underlies IBD immunopathogenesis. In this review, we attempt to clarify the roles played by RIPK2 in the development of IBD by focusing on its associated signaling pathways. We also discuss the possibility of using RIPK2 as a new therapeutic target in IBD.

ATG16L1 negatively regulates RICK/RIP2-mediated innate immune responses

Polymorphisms in the autophagy-related protein 16 like 1 (ATG16L1) and nucleotide-binding oligomerization domain 2 (NOD2) genes are associated with Crohn's disease (CD). Impaired interaction between ATG16L1 and NOD2 underlies CD immunopathogenesis. Although activation of the receptor-interacting serine/threonine kinase (RICK, also known as RIP2), a downstream signaling molecule for NOD2 and multiple toll-like receptors (TLRs), plays a pathogenic role in the development of inflammatory bowel disease, the molecular interaction between ATG16L1 and RICK/RIP2 remains poorly understood. In this study, we examined the physical interaction between ATG16L1 and RICK/RIP2 in human embryonic kidney 293 (HEK293) cells and human monocyte-derived dendritic cells (DCs) expressing excessive and endogenous levels of these proteins, respectively. We established that ATG16L1 binds to RICK/RIP2 kinase domain and negatively regulates TLR2-mediated nuclear factor-kappa B (NF-κB) activation and proinflammatory cytokine responses by inhibiting the interaction between TLR2 and RICK/RIP2. Binding of ATG16L1 to RICK/RIP2 suppressed NF-κB activation by downregulating RICK/RIP2 polyubiquitination. Notably, the percentage of colonic DCs expressing ATG16L1 inversely correlated with IL-6 and TNF-α expression levels in the colon of CD patients. These data suggest that the interaction between ATG16L1 and RICK/RIP2 maintains intestinal homeostasis via the downregulation of TLR-mediated proinflammatory cytokine responses.

Tumor invasion to the arteries feeding the gallbladder as a novel risk factor for cholecystitis after metallic stent placement in distal malignant biliary obstruction

BACKGROUND AND AIM

Cholecystitis is a major complication after self-expandable metallic stent (SEMS) placement for malignant biliary obstruction. Ischemia is one of the risk factors for cholecystitis, but little is known about the influence of tumor invasion to the feeding artery of the gallbladder on the onset of cholecystitis after SEMS placement. The aim of the present study was to identify risk factors for cholecystitis after SEMS placement.

METHODS

Incidence and nine predictive factors of cholecystitis were retrospectively evaluated in 107 patients who underwent SEMS placement for unresectable distal malignant biliary obstruction at Kyoto University Hospital and Otsu Red Cross Hospital between January 2012 and June 2016.

RESULTS

Cholecystitis occurred in 13 of 107 patients (12.1%) after SEMS placement during the median follow-up period of 262 days. Univariate analyses showed that tumor invasion to the feeding artery of the gallbladder and tumor involvement to the orifice of the cystic duct were significant predictors of cholecystitis (P = 0.001 and P < 0.001). Multivariate analysis confirmed that these two factors were significant and independent risks for cholecystitis with odds ratios of 22.13 (95% CI, 3.57-137.18; P = 0.001) and 25.26 (95% CI, 4.12-154.98; P < 0.001), respectively.

CONCLUSIONS

This study showed for the first time that tumor invasion to the feeding artery of the gallbladder as well as tumor involvement to the orifice of the cystic duct are independent risk factors for cholecystitis after SEMS placement.

Intestinal epithelial culture under an air-liquid interface: a tool for studying human and mouse esophagi

This study investigated whether an intestinal epithelial culture method can be applied to mouse and human esophageal cultures. The esophagi harvested from 1-day-old mice and adult humans were maintained in collagen gels. A commercially available culture medium for human embryonic stem cells was used for the human esophageal culture. We discovered that the intestinal epithelial culture method can be successfully applied to both mouse and human esophageal cultures. The long-term cultured esophageal organoids were rod-like luminal structures lined with myofibroblasts. We discovered that regeneration of the esophageal mucosal surface can be almost completely achieved in vitro, and the advantage of this method is that organoid cultures may be generated using host-derived fibroblasts as a niche. This method is a promising tool for mouse and human research in intestinal biology, carcinogenesis, and regenerative medicine.

Serum miR-21, miR-29a, and miR-125b Are Promising Biomarkers for the Early Detection of Colorectal Neoplasia

PURPOSE

Circulating microRNAs (miRNA) are emerging as promising diagnostic biomarkers for colorectal cancer, but their usefulness for detecting early colorectal neoplasms remains unclear. This study aimed to identify serum miRNA biomarkers for the identification of patients with early colorectal neoplasms.

EXPERIMENTAL DESIGN

A cohort of 237 serum samples from 160 patients with early colorectal neoplasms (148 precancerous lesions and 12 cancers) and 77 healthy subjects was analyzed in a three-step approach that included a comprehensive literature review for published biomarkers, a screening phase, and a validation phase. RNA was extracted from sera, and levels of miRNAs were examined by real-time RT-PCR.

RESULTS

Nine miRNAs (miR-18a, miR-19a, miR-19b, miR-20a, miR-21, miR-24, miR-29a, miR-92, and miR-125b) were selected as candidate biomarkers for initial analysis. In the screening phase, serum levels of miR-21, miR-29a, and miR-125b were significantly higher in patients with early colorectal neoplasm than in healthy controls. Elevated levels of miR-21, miR-29a, and miR-125b were confirmed in the validation phase using an independent set of subjects. Area under the curve (AUC) values for serum miR-21, miR-29a, miR-125b, and their combined score in discriminating patients with early colorectal neoplasm from healthy controls were 0.706, 0.741, 0.806, and 0.827, respectively. Serum levels of miR-29a and miR-125b were significantly higher in patients who had only small colorectal neoplasms (≤5 mm) than in healthy subjects.

CONCLUSIONS

Because serum levels of miR-21, miR-29a, and miR-125b discriminated patients with early colorectal neoplasm from healthy controls, our data highlight the potential clinical use of these molecular signatures for noninvasive screening of patients with colorectal neoplasia.

Simultaneous optical mapping system of endocardial and epicardial excitation

The cardiac excitation propagation during arrhythmia shows a three-dimensional complex excitation behavior. Numerous optical measurements of the propagation and action potentials of the cardiac muscles have been made to elucidate the detailed arrhythmia phenomenon. The conventional optical measurement system mainly observes the action potential signal of the epicardium, and the endocardial signal measurement without incising the heart is difficult. In addition, an incised heart no longer exhibits the natural excitation behavior. Therefore, we constructed a simultaneous measurement system that integrates the conventional epicardial measurement system and the endocardial measurement system by using an endoscope for an intact heart. Then, we proposed a line-laser registration method that can match correspondence between the epicardial and endocardial images for a short period. We demonstrated that this registration method has a sub-millimeter accuracy. Subsequently, we succeeded in simultaneous optical measurement of the excitation propagation of the epicardium and endocardium of the right heart wall by using an isolated rabbit heart.

Abstract 867: Serum microRNAs as diagnostic biomarkers for early colorectal neoplasms

Objectives: Early detection of precancerous lesions and early-stage cancers are essential to reduce mortality from colorectal cancer (CRC).

Serum/plasma microRNAs (miRs) have been reported as diagnostic and prognostic biomarkers of CRC, but their utility in detecting patients with early lesions has not been fully explored. The aim of this study is to identify serum miRs which are potentially useful as diagnostic biomarkers for early colorectal neoplasms, and potential confounders in a blood test.

Methods: Candidate biomarker miRs were selected from previously published studies. Serum samples were collected from patients with low-grade intraepithelial neoplasias (LGINs) including tubular adenomas and tubulovillous adenomas, high-grade intraepithelial neoplasias (HGINs), early cancers, and healthy volunteers, and divided into discovery and validation sets. Total RNA was extracted from serum samples and levels of candidate miRs were measured by real-time RT-PCR. To evaluate the impact of hemolysis on serum miR levels, serially diluted hemolysed controls were prepared from stock solution made by hemolysing the red blood cells in distilled water. Levels of candidate miRs in hemolysed controls were also examined by real-time RT-PCR. Absorbance of serum samples at 560 nm, 576 nm, and 592 nm was measured by spectrophotometry and hemoglobin levels were estimated from a standard curve.

Results: Fourteen miRs were selected as candidate diagnostic biomarkers of early colorectal neoplasms from a review of the literature. Serum levels of five miRs were too low to be accurately quantified by real-time RT-PCR, and excluded from further evaluation. Sera from 12 patients with LGINs, 8 patients with HGINs, 4 patients with cancers, and 25 healthy volunteers were included in the discovery phase. Of 9 miRs examined, miR21 (p = 0.0007), miR29a (p &lt; 0.0001) and miR125b (p = 0.0198) showed significantly higher levels in sera from early colorectal neoplasms compared to those from healthy volunteers. Higher levels of miR29a and miR125b in sera from early colorectal neoplasms were confirmed in the validation phase using independent set of samples. Levels of miR21, 29a, and miR125b in sera significantly correlated with the degree of hemolysis.

Conclusions: Serum miRs may be useful biomarkers to detect patients with early colorectal neoplasia, including adenomas. Hemolysis affects serum miR levels, and will confound measurement. Since hemolysis occurs frequently during blood collection, its impact on serum miRs should be further investigated.

Citation Format: Atsushi Yamada, Takahiro Horimatsu, Yoshinaga Okugawa, Naoshi Nishida, Tadayuki Kou, Toshihiro Kusaka, Hajime Honjo, Yusuke Amanuma, Osamu Kikuchi, Manabu Muto, Ajay Goel, C. Richard Boland. Serum microRNAs as diagnostic biomarkers for early colorectal neoplasms. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 867. doi:10.1158/1538-7445.AM2014-867

Design and fabrication of a perpendicular magnetic tunnel junction based nonvolatile programmable switch achieving 40% less area using shared-control transistor structure

A compact nonvolatile programmable switch (NVPS) using 90 nm CMOS technology together with perpendicular magnetic tunnel junction (p-MTJ) devices is fabricated for zero-standby-power field-programmable gate array. Because routing information does not change once it is programmed into an NVPS, high-speed read and write accesses are not required and a write-control transistor can be shared among all the NVPSs, which greatly simplifies structure of the NVPS. In fact, the effective area of the proposed NVPS is reduced by 40% compared to that of a conventional MTJ-based NVPS. The instant on/off behavior without external nonvolatile memory access is also demonstrated using the fabricated test chip.

[A case of endocrine carcinoma of the cecum treated with CDDP/VP-16]

A 41-year-old man was admitted to our hospital because of multiple liver tumors. Colonoscopy showed a mass lesion in the cecum. He was given a diagnosis of endocrine cell carcinoma by immunostaining technique, and received chemotherapy of CAPOX regimen for 3 courses. After that, he underwent second-line chemotherapy of EP(CDDP/VP-16)regimen due to deterioration of his performance status(PS), and his tumor marker NSE. He then showed dramatically improved PS, and improvement in the size of liver mets and NSE(4. 3mg/mL).

Multicenter phase II randomized study evaluating dose-response of antiperistaltic effect of L-menthol sprayed onto the gastric mucosa for upper gastrointestinal endoscopy

AIM

Peppermint oil solution was found to be effective for reducing gastric spasm during upper gastrointestinal endoscopy. The aim of the present study was to assess whether the gastric peristalsis-suppressing effect is dose-dependently induced by L-menthol, the major constituent of peppermint oil, and to determine the recommended dose of an L-menthol preparation.

METHODS

In this phase II, multicenter, double-blind, dose-response study, 131 eligible patients were randomly assigned to receive 20 mL of 0.4% L-menthol (n = 32), 0.8% L-menthol (n = 35), 1.6% L-menthol (n = 30), or placebo (n = 34). The primary efficacy measure was the proportion of subjects with no peristalsis in two time periods, 75 to 105 s after treatment and immediately before the completion of endoscopy.

RESULTS

The peristalsis-suppressing effect of L-menthol increased dose dependently (5.6%, 32.0%, 47.4% and 52.9% in the 0%, 0.4%, 0.8% and 1.6% groups, respectively: P < 0.001, one-tailed Cochran-Armitage trend test). As compared with the placebo group, the proportion of subjects with no peristalsis after administration was significantly higher in the 0.8% group (P = 0.015) and 1.6% group (P = 0.009). Adverse events in the L-menthol dose groups occurred with similar frequencies in the placebo group.

CONCLUSION

L-menthol suppresses peristalsis in a dose-dependent manner, and the dose-response reaches a plateau at 0.8% L-menthol. Further Phase III studies are needed to establish the superiority of 0.8% L-menthol over placebo.

Antiperistaltic effect and safety of L-menthol sprayed on the gastric mucosa for upper GI endoscopy: a phase III, multicenter, randomized, double-blind, placebo-controlled study

BACKGROUND

GI peristalsis during GI endoscopy commonly requires intravenous or intramuscular injection of antispasmodic agents, which sometimes cause unexpected adverse reactions.

OBJECTIVE

Our ultimate goal was to evaluate whether the antiperistaltic effect of L-menthol-based preparations facilitates endoscopic examinations in a clinical setting.

DESIGN

Multicenter, randomized, double-blind, placebo-controlled study.

SETTING

Six Japanese referral centers.

PATIENTS AND INTERVENTION

A total of 87 patients scheduled to undergo upper GI endoscopy were randomly assigned to receive 160 mg of L-menthol (n=45) or placebo (n=42). Both treatments were sprayed endoscopically on the gastric mucosa. The degree of gastric peristalsis was assessed by an independent committee.

MAIN OUTCOME MEASUREMENTS

The proportion of subjects with no peristalsis 90 to 135 seconds after administration and at the end of the endoscopic examination (complete suppression of gastric peristalsis). Other outcomes were the proportion of subjects with no or mild peristalsis (adequate suppression of gastric peristalsis) and the ease of intragastric observation as evaluated by the endoscopist who performed the procedure.

RESULTS

Gastric peristalsis was completely suppressed in 35.6% (21.9, 51.2) of the L-menthol group compared with only 7.1% (1.5, 19.5) of the placebo group (P<.001). In the L-menthol group, 77.8% (62.9, 88.8) (35/45 subjects) of the subjects had no or mild peristalsis at the completion of endoscopy. Minor peristalsis interfered with intragastric examination in only 1 of these 35 patients (2.9%). The incidence of adverse events did not differ significantly between the groups (P=.512).

LIMITATION

Small sample size.

CONCLUSIONS

During upper GI endoscopy, L-menthol sprayed on the gastric mucosa significantly suppresses peristalsis with minimal adverse drug reactions compared with placebo. (

CLINICAL TRIAL REGISTRATION NUMBER

NCT00742599.).

Dose effects of oral estradiol on bone mineral density in Japanese women with osteoporosis

OBJECTIVES

This 2-year study compared 0.5 and 1.0 mg oral estradiol (E(2)), with or without levonorgestrel (LNG), for the treatment of postmenopausal osteoporosis in Japanese women.

METHODS

Japanese women with osteoporosis after natural menopause or bilateral oophorectomy were randomized to receive E(2) 0.5 or 1.0 mg/day with LNG 40 microg as required, or placebo, for 52 weeks. Women treated with E(2) in the first year continued therapy at the same doses in the second year. Efficacy, safety and pharmacokinetics were assessed.

RESULTS

There were 73 women randomized to E(2) 0.5 mg, 157 to E(2) 1.0 mg and 79 to placebo. Lumbar bone mineral density at 52 weeks increased significantly more with E(2) 1.0 mg (p < 0.001) and 0.5 mg (p < 0.001) than with placebo (no change). After 2 years, a 10% increase in bone mineral density with E(2) 1.0 mg was significantly greater than with E(2) 0.5 mg (8%; p = 0.008). E(2) was associated with an acceptable safety and tolerability profile, with slightly more adverse events with E(2) 1.0 than 0.5 mg. Serum E(2) concentration increased in a dose-dependent manner.

CONCLUSION

This study showed that E(2), at both 1.0 mg and 0.5 mg doses, was effective in increasing bone mineral density with an acceptable safety and tolerability profile in Japanese postmenopausal women with osteoporosis but that the bone mineral density response was higher with the 1.0 mg dose.

Association of renal artery stenosis with aortic jet velocity in hypertensive patients with aortic valve sclerosis

BACKGROUND

Patients with aortic valve sclerosis (AVS) have an increased risk of cardiovascular events. Patients with atherosclerotic renal artery stenosis (RAS) develop resistant hypertension and heart failure. We hypothesized AVS may be copresent with RAS in hypertensive patients.

METHODS

Hypertensive patients with AVS (n = 167) underwent magnetic resonance (MR) angiography using nonenhanced steady-state free precession (SSFP) technique. More than 75% luminal narrowing in the proximal region of main renal artery was regarded as significant RAS. Peak aortic jet velocity was obtained by Doppler echocardiography. We measured brain natriuretic peptide (BNP), and estimated glomerular filtration rate (GFR) using the Modification of Diet in Renal Disease equation.

RESULTS

Unilateral or bilateral RAS was detected in 40 patients. AVS patients with RAS were older (78 +/- 6 vs. 74 +/- 8 years), and had higher levels of aortic jet velocity (162 +/- 4 vs. 144 +/- 3 cm/s), and lower levels of GFR (55 +/- 13 vs. 62 +/- 14 ml/min/1.73 m(2)) than those without RAS. Higher aortic jet velocity (odds ratio (OR) = 1.58, 95% confidence interval (CI) = 1.09-2.31) and lower GFR (OR = 0.54, 95% CI = 0.33-0.38) were associated with the presence of RAS, after being adjusted for age, systolic blood pressure, and BNP.

CONCLUSIONS

RAS was detected in hypertensive patients with AVS, particularly in patients with higher aortic jet velocity and lower GFR. Higher aortic jet velocity and lower GRF may be useful as a potential indicator for those needing assessment of RAS for risk stratification and deserves further study.

Incidence of Carboplatin-related hypersensitivity reactions in Japanese patients with gynecologic malignancies

Carboplatin is one of the most commonly used and well-tolerated agents for gynecologic malignancies. The rate of hypersensitivity reactions (HSRs) in the overall population of patients receiving carboplatin has been reported to increase after multiple doses of the agent. We retrospectively analyzed the incidence, clinical features, management, or outcome of carboplatin-related HSRs in 113 Japanese patients with gynecologic malignancies and the possibility of rechallenge with the drug. We intravenously administered carboplatin after paclitaxel or docetaxel. Mild HSRs are resolved by temporary interruption of carboplatin infusion, an additional antihistamine, and/or a corticosteroid. If HSRs arose, carboplatin was diluted, not exceeding 1 mg/mL, and slowly infused over 2 hours in subsequent cycles. Ten patients experienced carboplatin HSRs, with an overall incidence of 8.85%. The first HSR episode was mild in all cases. When retreated with carboplatin, 4 exhibited severe HSRs. More than 9 cycles and/or more than 5000 mg of carboplatin administration significantly increased the incidence of HSRs. In particular, carboplatin treatment beyond 15 cycles and/or 8000 mg increased the risk of severe HSRs (P < 0.0001). The incidence of HSRs in the ovarian carcinoma group was significantly greater than that in the uterine carcinoma group (P = 0.0046). Careful attention should be paid to HSRs during carboplatin treatment beyond 9 cycles and/or 5000 mg. The rate of severe HSRs greatly increases beyond 15 cycles and/or 8000 mg. Further studies are needed to identify potential risk factors that may contribute to the development of carboplatin HSRs and to decrease the risk of reactions.

Role of Ca2+ mobilization and Ca2+ sensitization in 8-iso-PGF 2 alpha-induced contraction in airway smooth muscle

BACKGROUND

Isoprostanes are prostaglandin (PG)-like compounds synthesized by oxidative stress, not by cyclooxygenase, and increase in bronchoalveolar lavage fluid of patients with asthma. The airway inflammation implicated in this disease may be amplified by oxidants. Although isoprostanes are useful biomarkers for oxidative stress, the action of these agents on airways has not been fully elucidated.

OBJECTIVE

This study was designed to determine the intracellular mechanisms underlying the effects of oxidative stress on airway smooth muscle, focused on Ca(2+) signalling pathways involved in the effect of 8-iso-PGF(2 alpha).

METHODS

Using simultaneous recording of isometric tension and F(340)/F(380) (an indicator of intracellular concentrations of Ca(2+), [Ca(2+)]i, we examined the correlation between tension and [Ca(2+)]i in response to 8-iso-PGF(2 alpha) in the fura-2 loaded tracheal smooth muscle.

RESULTS

Augmented tension and F(340)/F(380) by 8-iso-PGF(2 alpha) were attenuated by ICI-192605, an antagonist of thromboxane A(2) receptors (TP receptors). Moreover, D609, an antagonist of phosphatidylcholine-specific phospholipase C, markedly reduced both the tension and F(340)/F(380) induced by 8-iso-PGF(2 alpha), whereas U73122, an antagonist of phosphatidylinositol-specific phospholipase C, modestly inhibited them by 8-iso-PGF(2 alpha). SKF96365, a non-selective antagonist of Ca(2+) channels, markedly reduced both tension and F(340)/F(380) by 8-iso-PGF(2 alpha). However, diltiazem and verapamil, voltage-dependent Ca(2+) channel inhibitors, modestly attenuated tension although their reduction of F(340)/F(380) was not different from that by SKF96365. Y-27632, an inhibitor of Rho-kinase, significantly attenuated contraction induced by 8-iso-PGF(2 alpha) without reducing F(340)/F(380), whereas GF109203X and Go6983, protein kinase C inhibitors, did not markedly antagonize them although reducing F(340)/F(380) with a potency similar to Y-27632.

CONCLUSION

8-iso-PGF(2 alpha) causes airway smooth muscle contraction via activation of TP receptors. Ca(2+) mobilization by SKF96365- and D609-sensitive Ca(2+) influx and Ca(2+) sensitization by Rho-kinase contribute to the intracellular mechanisms underlying the action of 8-iso-PGF(2 alpha). Rho-kinase may be a therapeutic target for the physiologic abnormalities induced by oxidative stress in airways.

Neoadjuvant chemotherapy with weekly carboplatin and paclitaxel for locally advanced cervical carcinoma

The efficacy and toxicity of neoadjuvant carboplatin and paclitaxel administered on a weekly schedule for locally advanced cervical carcinoma were evaluated. Thirty patients staged as IB2-IVA according to the FIGO were treated with carboplatin (AUC 2; an area under the time-concentration of 2 mg*min/ml based on creatinine clearance) and paclitaxel (60 mg/m(2)) intravenously, every week for six cycles. A type III radical hysterectomy was then undertaken. Thirty patients were enrolled in this study. An objective response was recorded in 26 patients (87%, 95% CI 70-95%). Progressive disease was not observed. Grade 3 neutropenia was observed in only two patients (7%), and grade 1 or 2 neuropathy was seen in six patients (20%). The combination of carboplatin and paclitaxel given in weekly schedule for advanced cervical carcinoma was highly active, permitting a high rate of subsequent surgical resectability. It was well tolerated. This regimen may provide improved outcomes with minimal toxicity.

Roles of P2X receptors and Ca2+ sensitization in extracellular adenosine triphosphate-induced hyperresponsiveness in airway smooth muscle

BACKGROUND

The release of adenosine triphosphate (ATP) from the airway epithelial cells during the inflammatory process is considered to play an important role in the pathophysiology of asthma and chronic obstructive pulmonary disease.

OBJECTIVE

This study was designed to determine whether extracellular ATP is involved in the bronchial hyperresponsiveness as an interaction between epithelium and smooth muscle in the airways.

METHODS

We examined the contractile response to methacholine (MCh) before and after exposure to low concentrations (< or = 10 microm) of ATP in isolated, epithelium-denuded guinea-pig tracheal smooth muscle by measuring isometric tension. Intracellular Ca2+ concentrations ([Ca2+]i) were assessed by fluorescent intensities of fura-2.

RESULTS

MCh-induced contractile force was increased with no change in [Ca2+]i after exposure to 10 microm ATP for 15 min. The ability of ATP to enhance the MCh-induced contraction was markedly attenuated by suramin, a non-selective P2 receptor inhibitor. Pre-incubation with ATPgammaS, a non-hydrolysable analogue of ATP and alpha,beta-meATP, a P2X agonist, also enhanced the MCh-induced contraction. In contrast, uracil triphosphate, a P2Y agonist, did not affect the MCh-induced contraction. Y-27632, a Rho-kinase inhibitor, suppressed the ability of ATP to enhance the MCh-induced contraction. Moreover, PP1 and PP2, Src tyrosin kinase inhibitors, suppressed the enhancement of MCh-induced contraction by ATP.

CONCLUSION

Pre-treatment with ATP induces hyperresponsiveness to MCh mediated by Ca2+ sensitization via the P2X receptor in airway smooth muscle. The present findings suggest the possible involvement of both the Rho-kinase and Src pathways in the intracellular mechanism of this phenomenon.

Predictive value of heart-type fatty acid-binding protein for left ventricular remodelling and clinical outcome of hypertensive patients with mild-to-moderate aortic valve diseases

Heart-type fatty acid-binding protein (H-FABP), a marker of acute myocardial infarction and a soluble cytosolic protein, may be released following left ventricular remodelling in cardiac overloaded hearts caused by hypertension, aortic regurgitation (AR) or aortic stenosis (AS). Our aim was to investigate if H-FABP levels are associated with left ventricular remodelling and clinical outcome in hypertensive patients with AR or AS. H-FABP and brain natriuretic peptide (BNP) were measured, glomerular filtration rate (GFR) was estimated using the modification of diet in renal disease (MDRD) equation, and left ventricular dimension at systole corrected for body surface area (LVDs/BSA) and relative wall thickness (RWT) were determined by echocardiography in hypertensive patients with mild-to-moderate AR (n=78), those with mild-to-moderate AS (n=73) and those without valvular heart diseases (HT) (n=50). H-FABP levels were significantly higher in AR (4.9+/-3 ng/ml) and in AS (4.5+/-3) than in HT (3.4+/-1) and BNP (65+/-73 pg/ml, 76+/-75, 35+/-22). H-FABP correlated with LVDs/BSA in AR (beta=0.23, P<0.05), and RWT in AS (beta=0.18, P<0.05) after adjustment for age, gender and all the other variables. AS and AR patients were prospectively followed up for cardiac events during 34+/-19 months. A multivariate Cox hazard analysis indicated H-FABP was an independent predictor of outcome both in AR (relative risk (RR)=7.61, 95% CI=2.39-25.3) and AS (RR=13.6, 95% CI=3.27-66.9). H-FABP, associated with left ventricular remodelling, is useful in predicting clinical outcome in hypertensive patients with mild-to-moderate aortic valve diseases.

Analysis of QT Interval Prolongation With Heart Failure by Simulation of Repolarization Process

It has been postulated that action potential duration (APD) is prolonged and I<inf>Ks</inf>, a slow component of delayed rectifier potassium current, decreases in heart failure. We have reported that QT interval is prolonged and expression weight of KCNE1, coding I<inf>Ks</inf>channel, increases in patients with heart failure. Since it is known that increase in KCNE1 increases the maximum conductance of I<inf>Ks</inf>channel, the mechanism of APD prolongation is not explained by over expression of KCNE1. In this study, we construct a cardiac membrane action potential simulation model based on the experimental data from Xenopus oocytes expressed KCNQ1 and KCNE1 to investigate the relationship between increase in KCNE1 and APD. In addition, we investigated effect of reduction in Ca²⁺-independent transient outward potassium current (I<inf>to</inf>) on APD in heart failure. In simulation, APD at 5ng KCNE1 was 180.96ms, which was 4.63% longer than that at 1ng KCNE1 (APD=172.96ms) and 55.9% longer than that at 0.2ng KCNE1 (APD=110.96ms. In the cases of KCNQ1 alone and 0.2ng KCNE1 coinjected, APD shortened as density of I<inf>to</inf>decreased, and APD prolonged as density of I<inf>to</inf>decreased in other cases. This study shows that increase in KCNE1 expression level makes maximum conductance of I<inf>Ks</inf>channel increase and I<inf>Ks</inf>channel open slowly and conductance of I<inf>Ks</inf>channel decrease according to the APD time scale. Therefore increasing the KCNE1 expression level may prolong APD with this mechanism. This method of constructing a simulation model based on experiments helps to explain the relationship between potassium currents and QT interval prolongation.

Involvement of reduced sensitivity to Ca in beta-adrenergic action on airway smooth muscle

BACKGROUND

It is well known that beta-adrenoceptor agonists (beta-agonists) cause relaxation in airway smooth muscle mediated by a reduction in the concentration of intracellular Ca2+ ([Ca2+](i)). However, little is currently known regarding whether reduced sensitization to Ca2+ is involved in the beta-adrenergic relaxation.

OBJECTIVE

This study was designed to determine the intracellular mechanisms underlying suppression of Ca2+ sensitization in beta-adrenergic relaxation (Ca(2+)-independent relaxation by beta-agonists). Methods Isometric tension and [Ca2+](i) were simultaneously measured in fura-2-loaded strips isolated from guinea-pig tracheal smooth muscles. The relationships between tension and [Ca2+](i) were examined in the inhibitory action of isoprenaline (ISO) and other cAMP-related agents against methacholine-induced contraction.

RESULTS

The concentration-inhibition curve for ISO against methacholine in tension was significantly dissociated from the curve for ISO in [Ca2+](i). In ISO-induced relaxation, a reduction in tension was significantly greater than that in [Ca2+](i.) This phenomenon was mimicked by other cAMP-related agents: forskolin and dibutyryl-cAMP. In contrast, the inhibitory action of SKF-96365, a non-selective inhibitor of Ca(2+) channels, was associated with that in [Ca2+](i). In the presence of Rp-cAMPS, an inhibitor of protein kinase A (PKA), ISO caused an equivalent relaxation with less reduction in [Ca2+](i). The effects of ISO were not affected by Y-27632, an inhibitor of Rho-kinase, or by bisindolylmaleimide, an inhibitor of protein kinase C. ISO failed to inhibit contraction elicited by calyculin A, an inhibitor of myosin phosphatase. Conclusion beta-Adrenergic action antagonizes not only Ca2+ mobilization but also Ca2+ sensitization in methacholine-induced contraction. The cAMP/PKA-independent, G(s)-direct action is more potent in Ca(2+)-independent relaxation by beta-agonists than the cAMP/PKA-dependent pathway. Moreover, myosin phosphatase is a fundamentally affected protein in the reduced response to Ca2+ mediated by beta-agonist. Our results may provide evidence that this Ca2+ desensitization is a novel target for a reliever medication using rapid-acting beta-agonists in acute asthma management.

Acute cholecystitis due to strangulation of a floating gallbladder by the lesser omentum

We report a unique case of acute cholecystitis due to strangulation of a floating gallbladder by the lesser omentum, which could be detected by abdominal ultrasonography. We believe this case to be the first case of reported literatures in English.

Case control study of hormone replacement therapy (HRT) and breast cancer in Japanese women

10012

Background: Some prospective studies in US and UK (represented by Women’s Health Initiative and Million Women Study) show that HRT use may increase the risk of breast cancer. However, it is unclear whether or not this perspective is applicable to Japanese women, due to several factors such as the difference in incidence of breast cancer, difference in HRT prevalence, which are to be concerned in this study. To investigate the relationship between HRT use and breast cancer, a case-control study was conducted in Japan. Methods: We sent self-administered questionnaire to 4,500 cases who have a previous history of confirmed histological breast cancer and 4,500 controls who were selected according to the inclusion criteria. All the subjects were between age 45 and 69 at the time of enrollment. Among these subjects, 3,434 in case group and 2,427 in control group sent back their questionnaire (total 5,861). The datacenter was run in Kitasato Univ. and the statistical analysis was performed using SAS (version 9.1). Control was selected by considering the screening record for GI disease and respiratory disorders, with no previous history of breast cancer, gynecological and hormonal disease at the time of screening. We asked about past history of exposure to the factors supposed to be breast cancer-causing; previous or current use of HRT, age at diagnosis, academic background, BMI, lifestyle habits, age of menarche, birth history, history of breast feeding, family history, use of contraceptive agents and menopausal status. Results: As the main analysis result, 164 (5.0%) out of 3,316 cases and 253 (7.4%) out of 2355 controls had used HRT (Odds ratio 0.432 [95% CI 0.352–0.530]. Conclusions: The result of this study shows that HRT users were less likely to develop breast cancer than never users. However, in this study, there was a difference in the observation period for the past use of HRT between cases and controls. Considering the transition of HRT prevalence in Japan, there may be a possibility that this difference can be a cause of a serious bias for the main analysis result. Further sensitivity analyses are needed to evaluate the robustness of the findings and this point is under consideration.

No significant financial relationships to disclose.

Connexins in the sinoatrial and atrioventricular nodes

The sinoatrial node (SAN) and the atrioventricular node (AVN) are specialized tissues in the heart: the SAN is specialized for pacemaking (it is the pacemaker of the heart), whereas the AVN is specialized for slow conduction of the action potential (to introduce a delay between atrial and ventricular activation during the cardiac cycle). These functions have special requirements regarding electrical coupling and, therefore, expression of connexin isoforms. Electrical coupling in the center of the SAN should be weak to protect it from the inhibitory electrotonic influence of the more hyperpolarized non-pacemaking atrial muscle surrounding the SAN. However, for the SAN to be able to drive the atrial muscle, electrical coupling should be strong in the periphery of the SAN. Consistent with this, in the center of the SAN there is no expression of Cx43 (the principal connexin of the working myocardium) and little expression of Cx40, but there is expression of Cx45 and Cx30.2, whereas in the periphery of the SAN Cx43 as well Cx45 is expressed. In the AVN, there is a similar pattern of expression of connexins as in the center of the SAN and this is likely to be in large part responsible for the slow conduction of the action potential.

Computer three-dimensional reconstruction of the sinoatrial node

BACKGROUND

There is an effort to build an anatomically and biophysically detailed virtual heart, and, although there are models for the atria and ventricles, there is no model for the sinoatrial node (SAN). For the SAN to show pacemaking and drive atrial muscle, theoretically, there should be a gradient in electrical coupling from the center to the periphery of the SAN and an interdigitation of SAN and atrial cells at the periphery. Any model should include such features.

METHODS AND RESULTS

Staining of rabbit SAN preparations for histology, middle neurofilament, atrial natriuretic peptide, and connexin (Cx) 43 revealed multiple cell types within and around the SAN (SAN and atrial cells, fibroblasts, and adipocytes). In contrast to atrial cells, all SAN cells expressed middle neurofilament (but not atrial natriuretic peptide) mRNA and protein. However, 2 distinct SAN cell types were observed: cells in the center (leading pacemaker site) were small, were organized in a mesh, and did not express Cx43. In contrast, cells in the periphery (exit pathway from the SAN) were large, were arranged predominantly in parallel, often expressed Cx43, and were mixed with atrial cells. An approximately 2.5-million-element array model of the SAN and surrounding atrium, incorporating all cell types, was constructed.

CONCLUSIONS

For the first time, a 3D anatomically detailed mathematical model of the SAN has been constructed, and this shows the presence of a specialized interface between the SAN and atrial muscle.

Early gallbladder carcinoma associated with primary sclerosing cholangitis and ulcerative colitis

Patients troubled with primary sclerosing cholangitis (PSC) and ulcerative colitis (UC) are at high risk for cholangiocarcinoma, whereas cancer of the gallbladder (GBC) is rarely reported to develop in that population. A Japanese man aged 62 years with a 14-year history of PSC and UC had been found to have a protruding lesion of the gallbladder by screening sonography. The preoperative examination suggested the lesion to be GBC at an early stage. Pathology examination after cholecystectomy proved that the lesion was papillary adenocarcinoma localized in the mucosal layer. Although the prognosis of GBC is poor, the outcome of cholecystectomy against early GBC is relatively good. Early detection of the tumor is required for a better prognosis of patients with GBC. According to the review of the literature, PSC and UC patients are regarded as a high-risk group not only for cholangiocarcinoma but also GBC. It is advocated that clinicians perform repeated radiographic examinations including sonography for patients with PSC and UC even if the diseases are being controlled.