Analysis of external pressure on the left calf in the Lloyd-Davies position during colorectal surgery.

PURPOSE: Well-leg compartment syndrome (WLCS) is a potentially life-threatening postoperative complication related to the Lloyd-Davies surgical position, which can place increased external pressure on the calf region. We conducted this study to analyze external pressure changes, by applying a leg holder system to the left calf region of patients placed in the Lloyd-Davies position during laparoscopic surgery. METHODS: The study participants were 50 patients who underwent laparoscopic surgery for colorectal cancer in the Lloyd-Davies position. We assessed the maximum external pressure (MEP) on the left calf region using a pressure-distribution measurement system. Intraoperative measurements were taken continuously, and the MEP was evaluated with the patient horizontal and every 30 min during surgery in the head and right-down tilt position. RESULTS: The intraoperative MEP increased gradually when the patient was in the head and right-down tilt position and decreased when the patient was returned to the horizontal position. The MEP was higher in patients aged < 60 years, those who were obese, and those with a thick calf circumference. Both body mass index (BMI) and the maximum left calf circumference (MLCC) were found to correlate with the MEP. CONCLUSIONS: In addition to a high BMI, which is a well-known risk factor for WLCS, a high MLCC should be considered another risk factor, especially for patients under 60 years.

Mismatch repair proteins immunohistochemical null phenotype in colon medullary carcinoma.

INTRODUCTION: In mismatch repair (MMR) immunohistochemistry, four MMR proteins' staining pattern reveals which particular gene may be defective. However, in the null phenotype, four MMR proteins are lost; consequently, it will be challenging to assume the target gene by immunohistochemistry and to determine whether deficient MMR was sporadic or germline. CASE REPORT: A 70-year-old man underwent right hemicolectomy with the diagnosis of ascending colon cancer. The postoperative histopathology revealed the diagnosis of medullary carcinoma and the loss of all four MMR expressions in immunohistochemistry. The mutation analysis using a peripheral blood sample showed no germline mutations in the four genes. DISCUSSION: This clinical case presents an unusual colon carcinoma that showed a MMR protein immunohistochemistry null phenotype. The cause of expression loss of MMR proteins can be explained by the loss of MLH1 and MSH2 functions associated with somatic loss of function mutations, functional loss in all four MMR proteins associated with somatic loss of function mutations, or Lynch-like syndrome. Correct interpretation and accumulation of relevant cases are necessary to unveil unusual cases in the era of universal screening.

Daikenchuto increases blood flow in the superior mesenteric artery in humans: A comparison study between four-dimensional phase-contrast vastly undersampled isotropic projection reconstruction magnetic resonance imaging and Doppler ultrasound.

Respiratory-gated four-dimensional phase-contrast vastly undersampled isotropic projection reconstruction (4D PC-VIPR) is magnetic resonance (MR) imaging technique that enables analysis of vascular morphology and hemodynamics in a single examination using cardiac phase resolved 3D phase-contrast magnetic resonance imaging. The present study aimed to assess the usefulness of 4D PC-VIPR for the superior mesenteric artery (SMA) flowmetry before and after flow increase was induced by the herbal medicine Daikenchuto (TJ-100) by comparing it with Doppler ultrasound (DUS) as a current standard. Twenty healthy volunteers were enrolled in this prospective single-arm study. The peak cross-sectionally averaged velocity was measured by 4D PC-VIPR, peak velocity was measured by DUS, and flow volume (FV) of SMA and aorta were measured by 4D PC-VIPR and DUS 25 min before and after the peroral administration of TJ-100. The peak cross-sectionally averaged velocity, peak velocity, and FV of SMA measured by 4D PC-VIPR and DUS significantly increased after administration of TJ-100 (4D PC-VIPR: the peak cross-sectionally averaged velocity; p = 0.004, FV; p = 0.035, DUS: the peak velocity; p = 0.003, FV; p = 0.010). Furthermore, 4D PC-VIPR can analyze multiple blood vessels simultaneously. The ratio of the SMA FV to the aorta, before and after oral administration on the 4D PC-VIPR test also increased (p = 0.015). The rate of change assessed by 4D PC-VIPR and DUS were significantly correlated (the peak cross-sectionally averaged velocity and peak velocity: r = 0.650; p = 0.005, FV: r = 0.659; p = 0.004). Retrospective 4D PC-VIPR was a useful modality for morphological and hemodynamic analysis of SMA.

Usefulness of a finger-mounted tissue oximeter with near-infrared spectroscopy for evaluating the intestinal oxygenation and viability in rats.

PURPOSE: To investigate the utility of the device for evaluating intestinal oxygenation and viability using an animal model. METHODS: Sprague-Dawley rats underwent laparotomy under general anesthesia, and the blood vessels in the terminal ileum were clamped to create ischemia. We measured the regional tissue oxygenation saturation (rSO2) using an oximeter after 1, 3, and 6 h of vessel clamping. Ischemic tissue damage was assessed using a histological score. The intestine was reperfused after each clamping period, and intestinal rSO2 and survival rate were evaluated. RESULTS: When reperfusion was performed at 1 and 3 h after ischemia, rSO2 increased after 10 min, and it improved to the same level as for normal intestine after 1 h; all rats survived for 1 week. In contrast, after 6 h of ischemia, rSO2 did not increase after reperfusion, and all animals died within 2 days. The histological scores increased after 1 h of reperfusion, with longer clamping periods. CONCLUSION: A finger-mounted tissue oximeter could evaluate intestinal ischemia and the viability, which is thus considered to be a promising result for future clinical application.

Successful laparoscopic approach for idiopathic adult colo-colonic intussusception: a case report.

BACKGROUND: Adult intussusception is recognized as an abdominal emergency. More than 90% of adult patients with intussusception have distinct causes that are related to benign or malignant tumors. In contrast, idiopathic intussusceptions, which are observed in children, are rare conditions in adult. Especially, colo-colonic idiopathic intussusceptions are rare among them. Surgery is traditionally considered the primary treatment option. Recently, laparoscopic surgery has been reported to be safe and feasible. However, laparoscopic surgical reduction, which is a common procedure in pediatric surgery, is not common in adult intussusception. CASE PRESENTATION: We report a 34-year-old man who presented with sudden abdominal pain. Computed tomography revealed the target sign in the transverse colon. There was no evidence of bowel obstruction, bowel wall edema, or tumor. We diagnosed idiopathic intussusception and selected laparoscopic procedure because of the strong abdominal pain experienced by the patient. There were no signs of perforation, bowel wall ischemia, or tumor in abdominal cavity. We confirmed idiopathic colo-colonic anterograde intussusception. Laparoscopic surgical reduction was achieved by a combination of delicate direct pressure on the anal side of the transverse colon and gentle pulling on the oral side. The patient's postoperative course was uneventful. CONCLUSIONS: We achieved successful surgical reduction laparoscopically because of an accurate preoperative diagnosis based on characteristic computed tomography features and appropriate surgical technique. Laparoscopic procedure and surgical reduction is considered to be an effective treatment strategy for adult idiopathic intussusceptions with severe symptoms.

A rectal neuroendocrine tumor in a patient with Crohn's disease: a case report and literature review.

Crohn's disease is recognized to increase the risk of gastrointestinal malignances. Adenocarcinoma is the most common malignancy in these patients. Association between Crohn's disease and adenocarcinoma in the small intestine has already been established, however, the association between neuroendocrine tumor and Crohn's disease remains uncertain. We report a 39-year-old man with Crohn's disease, who was diagnosed with NET in the rectum. He had suffered from fever and anal pain due to the anal fistula and abscess. The disease state was considered to be resistant to medical treatment. He underwent total proctocolectomy, small bowel resection, anal fistula drainage with ileostomy. Postoperative histology revealed a neuroendocrine tumor in the rectum. His postoperative course was uneventful, and he followed a good course under treatment with infliximab and mercaptopurine hydrate. This case highlights the need of careful observation of resected specimens in light of the possibility of NET, especially those with anal disorders.

Tenascin-C Produced by Intestinal Myofibroblasts Promotes Colitis-associated Cancer Development Through Angiogenesis.

BACKGROUND: Colitis-associated cancer (CAC) is one of the prognostic factors in inflammatory bowel disease (IBD), and prevention of CAC is a critical concern for patients with IBD. Component cells of the microenvironment, especially myofibroblasts, are known to affect tumor development, but the role of intestinal myofibroblasts (IMFs) in CAC has not been clarified. Here, we explored the role of IMFs in CAC and sought to identify candidate genes as novel therapeutic targets for the prevention of CAC. METHODS: We used the azoxymethane (AOM)/dextran sodium sulfate (DSS) model for dysplasia and CAC. Flow cytometry and RNA sequencing (RNA-seq) were performed to obtain an unbiased gene expression profile of IMFs. The transcriptome of significantly differentially expressed genes was analyzed by RNA-seq, quantitative reverse transcriptase polymerase chain reaction, and immunohistochemistry. RESULTS: Comparison of normal intestinal fibroblasts and IMFs revealed 1045 genes with significantly differential expression. Among them, we focused on tenascin-C (TNC; q = 0.00232, Log2(Fold Change) = 3.87). Tenascin-C gene expression was markedly increased in the dysplasia model compared with control and CAC model (P < 0.05). Tenascin-C protein was barely expressed in normal and nondysplastic mucosa but strongly expressed in the stroma around dysplastic lesions. Moreover, TNC surrounded and enclosed integrin αvß3-positive microvessels. Administration of ATN-161, an antagonist of αvß3-integrin, significantly suppressed tumorigenesis of CAC through inhibition of angiogenesis (P < 0.05). CONCLUSIONS: In the early stages of CAC, TNC produced by IMFs affects tumor development via integrin αvß3-mediated angiogenesis. Intestinal myofibroblasts might be a novel therapeutic target for preventing CAC.

In situ immunohistochemical detection of intracellular Mycoplasma salivarium in the epithelial cells of oral leukoplakia.

BACKGROUND: Mycoplasmas are the smallest free-living organisms; Mycoplasma salivarium and Mycoplasma orale are the most common species isolated from the oropharynx. Oral leukoplakia is the most prevalent potentially malignant disorder of the oral mucosa; its etiology has not been defined. Our previous study with DNA-binding fluorescent dye suggested the presence of mycoplasmas in the epithelial cells of leukoplakia tissue. OBJECTIVE: Our aim was to detect M. salivarium in the epithelial cells of leukoplakia by immunohistochemistry. DESIGN: We produced a polyclonal antibody (PAb) reactive to Mycoplasma by injecting a rabbit with M. salivarium cells (ATCC 23064) mixed with complete Freund's adjuvant and a monoclonal antibody specific to M. salivarium by injecting M. salivarium cells (ATCC 23557) mixed with complete Freund's adjuvant into the footpads of a rat. Then, we attempted to detect M. salivarium in the epithelium of leukoplakia tissues by immunohistochemistry. RESULTS: We obtained an antimycoplasma rabbit PAb reactive to all seven Mycoplasma species used in this study. Three hybridoma clones producing monoclonal antibodies specific to M. salivarium were obtained, and an M. salivarium-specific monoclonal antibody, designated 7-6H, was established. Immunohistochemistry with these antibodies revealed M. salivarium in the epithelial cells of leukoplakia with hyperplasia and hyperkeratosis on histology. PCR and sequencing verified the presence of M. salivarium DNA in the epithelial cells of leukoplakia. CONCLUSION: Intracellular M. salivarium was identified in the epithelial cells of leukoplakia.