A large multicenter cohort on the use of full-thickness resection device for difficult colonic lesions.

BACKGROUND: Introduction of the full-thickness resection device (FTRD) has allowed endoscopic resection of difficult lesions such as those with deep wall origin/infiltration or those located in difficult anatomic locations. The aim of this study is to assess the outcomes of the FTRD among its early users in the USA. METHODS: Patients who underwent endoscopic full-thickness resection (EFTR) for lower gastrointestinal tract lesions using the FTRD at 26 US tertiary care centers between 10/2017 and 12/2018 were included. Primary outcome was R0 resection rate. Secondary outcomes included rate of technical success (en bloc resection), achievement of histologic full-thickness resection (FTR), and adverse events (AE). RESULTS: A total of 95 patients (mean age 65.5 ± 12.6 year, 38.9% F) were included. The most common indication, for use of FTRD, was resection of difficult adenomas (non-lifting, recurrent, residual, or involving appendiceal orifice/diverticular opening) (66.3%), followed by adenocarcinomas (22.1%), and subepithelial tumors (SET) (11.6%). Lesions were located in the proximal colon (61.1%), distal colon (18.9%), or rectum (20%). Mean lesion diameter was 15.5 ± 6.4 mm and 61.1% had a prior resection attempt. The mean total procedure time was 59.7 ± 31.8 min. R0 resection was achieved in 82.7% while technical success was achieved in 84.2%. Histologically FTR was demonstrated in 88.1% of patients. There were five clinical AE (5.3%) with 2 (2.1%) requiring surgical intervention. CONCLUSIONS: Results from this first US multicenter study suggest that EFTR with the FTRD is a technically feasible, safe, and effective technique for resecting difficult colonic lesions.

Gene Expression Profiling of Peripheral Blood From Kidney Transplant Recipients for the Early Detection of Digestive System Cancer.

BACKGROUND: Kidney transplant recipients are at increased risk of developing cancer in comparison with the general population. To effectively manage post-transplantation malignancies, it is essential to proactively monitor patients. A long-term intensive screening program was associated with a reduced incidence of cancer after transplantation. This study evaluated the usefulness of the gene expression profiling of peripheral blood samples obtained from kidney transplant patients and adopted a screening test for detecting cancer of the digestive system (gastric, colon, pancreas, and biliary tract). STUDY DESIGN AND METHOD: Nineteen patients were included in this study and a total of 53 gene expression screening tests were performed. The gene expression profiles of blood-delivered total RNA and whole genome human gene expression profiles were obtained. We investigated the expression levels of 2665 genes associated with digestive cancers and counted the number of genes in which expression was altered. A hierarchical clustering analysis was also performed. The final prediction of the cancer possibility was determined according to an algorithm. RESULTS: The number of genes in which expression was altered was significantly increased in the kidney transplant recipients in comparison with the general population (1091 ± 63 vs 823 ± 94; P = .0024). The number of genes with altered expression decreased after the induction of mechanistic target of rapamycin (mTOR) inhibitor (1484 ± 227 vs 883 ± 154; P = .0439). No cases of possible digestive cancer were detected in this study period. CONCLUSION: The gene expression profiling of peripheral blood samples may be a useful and noninvasive diagnostic tool that allows for the early detection of cancer of the digestive system.

Initial experience with a tailor-made simulation and navigation program using a 3-D printer model of kidney transplantation surgery.

INTRODUCTION: Three-dimensional (3-D) printing systems allow for the creation of surgical models mimicking real tissue. We developed a kidney graft and pelvic cavity replica as a patient-specific 3-D model using a 3-D printing system with simultaneous jetting of different materials and subsequently evaluated the usefulness of surgical simulation and navigation of living kidney transplantation. METHODS: After generating a stereolithographic file of the organ surface based on multidetector computed tomographic data, we created a 3-D organ model using an inkjet 3-D printer and manufactured a pelvic cavity replica using patient-specific data. RESULTS: The patients' individual 3-D printed models were used to plan and guide the surgical procedures for laparoscopic donor nephrectomy and recipient transplantation surgery. The 3-D organ replicas obtained using transparent materials allowed for the creation of models that showed the visceral organs, blood vessels, and other details, thereby overcoming the limitations of conventional image-guided navigation. Our pelvic replicas can be made according to each patient's specific anatomical data, thus representing personalized surgical procedures. This level of detail of the anatomy enables the surgeons and trainees to virtually treat various pelvic conditions before they perform the surgical procedure. The use of these replicas may also reduce the length of the operation and provide better anatomical reference tools for tailor-made simulation and navigation of kidney transplantation surgery, consequently helping to improve training for the operating room staff, students, and trainees. CONCLUSIONS: We believe that our sophisticated personalized donor graft and pelvic replications obtained using a 3-D printing system are advantageous for kidney transplantation surgery.

Nutritional status in Japanese renal transplant recipients with long-term graft survival.

BACKGROUND: Nutritional status affects clinical outcomes in patients with chronic renal failure. Glucose intolerance, dyslipidemia, obesity, hypertension, and a calcium-phosphorus-vitamin D imbalance are the major nutritional and metabolic problems that occur in posttransplant patients. In this study, we assessed the daily intake in long-term renal transplant recipients to determine whether they have sufficient nutrients based on the Japanese nutrition recommendations (recommended dietary allowances [RDA] in Japan 2010). SUBJECTS AND METHODS: Thirty-one renal allograft recipients followed for >10 years (median, 16.3) were recruited. The median serum creatinine level was 1.2 g/dL (95% CI, 0.6-3.4). We estimated the intake of nutrients, including protein and salt, using a simple food frequency questionnaire. RESULTS: The median body mass index was 20.1 kg/m(2). The median total energy intake was 1566 kcal/d (95% CI, 892-2556). The daily intake of protein and salt was 65.1 and 9.1 g/d, respectively. The calcium, iron, vitamin D, and vitamin K intakes were 423 mg, 7.0 mg/d, 9.7 µg/d, and 197 µg/d, respectively. Patients with dyslipidemia displayed greater amounts of lipid and calcium than those with normal lipid levels. DISCUSSION: Our findings suggest that long-term renal transplant recipients in Japan seem to restrict caloric intake, while maintaining appropriate intake of protein, lipids, carbohydrates, and vitamins A, D, and K. However, daily calcium and iron intake were insufficient; salt intake was greater than the recommended dietary allowances in all subjects. In patients with dyslipidemia, calcium intake was lower than those in patients without dyslipidemia, although their intake of lipids was also lower than those without dyslipidemia. CONCLUSION: Nutritional guidance beginning during the early posttransplant phase helps to foster a healthy body mass index and nutritional balances for long-term renal transplant recipients. However, greater salt restriction was needed, and additional nutritional guidance aiming to prevent osteoporosis seems to be considered.

Utility of glucagon stimulation test in type 1 diabetes after pancreas transplantation.

BACKGROUND: Despite recent progress of immunosuppressive therapy with newly developed agents, long-term pancreatic graft survival after pancreas transplantation still remains low. Therefore, precise assessment of ß-cell function after pancreas transplantation is necessary. METHODS: Pancreatic ß-cell secretory activity was measured by means of the peripheral plasma fasting serum C-peptide (CPR) response to 1 mg of glucagon intravenously in 23 patients after pancreas transplantation. The utility of ΔCPR after injection was compared with other indices that reflect insulin secretion. RESULTS: When we performed the test, 6 patients still needed insulin injection after the transplantation. Mean CPR before and after glucagon intravenously were 1.9 ± 0.98 ng/mL and 4.6 ± 2.29 ng/mL, respectively. Fasting serum CPR, secretory unit of islet in transplantation (SUIT) index, and ΔCPR after glucagon injection were significantly different between insulin users and nonusers. During follow-up (501 ± 228 days), 3 patients could stop using insulin, and their increase of CPR (1.8 ± 0.5 ng/mL) was significantly higher than that in continuous insulin users (0.3 ± 0.3 ng/mL). CONCLUSION: Fasting CPR, SUIT index, and ΔCPR after glucagon injection could reflect ß-cell function for post-pancreas transplant patients, and glucagon stimulation test could give us additional information to predict insulin-free treatment.

An obligatory role for lung infiltrating B cells in the immunopathogenesis of obliterative airway disease induced by antibodies to MHC class I molecules.

Using a murine model, we demonstrated that endobronchial administration of antibodies (Abs) to major histocompatibility complex (MHC) class I results in cellular infiltration, epithelial metaplasia, fibrosis and obstruction of the small airways (obliterative airway disease [OAD]) mediated predominantly by Th17 responses to self-antigens. This resembles bronchiolitis obliterans syndrome developed following human lung transplantation. Since B cells play a crucial role in induction of autoimmune responses, we defined the role of B cells and its antigen presenting properties in induction of OAD in this study. Anti-MHC class I was administered endobronchially in B(-/-) and wild-type mice. In contrast to wild type, B(-/-) animals did not demonstrate cellular infiltration, epithelial metaplasia and obstruction of airways following anti-MHC. Frequency of K-α1 tubulin and CollagenV-specific IL-17 cells was significantly decreased in B(-/-) mice. As expected, Abs against self-antigens and germinal center formation were not developed in B(-/-) mice. Thus, we conclude that B cells and its antigen presenting capacity play an important role in induction of immune responses to self-antigens and immunopathogenesis of OAD following the administration of anti-MHC. Therefore, strategies to block B-cell and its antigen presenting functions should be considered for preventing the development of chronic rejection.

EUS-guided choledochoduodenostomy for palliative biliary drainage in patients with malignant biliary obstruction: results of long-term follow-up.

Five patients with obstructive jaundice caused by malignant periampullary biliary stenosis underwent EUS-guided choledochoduodenostomy (EUS-CDS) from the first portion of the duodenum using a convex echoendoscope and a needle knife. All the steps of the procedure including passage dilatation and the plastic stent placement were performed through the accessory channel of the echoendoscope over the guide wire. Stent insertion was technically successful in all five patients. The procedure was also clinically effective in relieving jaundice in all cases. One patient developed pneumoperitoneum, which resolved with conservative management. Stent exchange was successful in seven of eight attempts in patients with stent occlusion. One failure was due to tumor invasion to the choledochoduodenal fistula. Stent patency was maintained in the remaining patients throughout their survival period. The average stent patency was 211.8 days. EUS-CDS from the first portion of the duodenum appears to be feasible and safe in cases of obstructive jaundice caused by distal bile duct obstruction.

IP-10, apoptotic genes, and calcineurin subtype messenger RNA kinetics occurring in rat renal isografts from brain-dead donors.

BACKGROUND: Brain death (BD) and following ischemia/reperfusion(I/R) injury has cardinal implications in kidney transplantation (Tx). We hypothesize that inflammation, apoptosis, and drug nephrotoxicity are central mechanisms leading to initial organ damage in transplantation from BD donors. In this study, the gene kinetics of a chemokine (IP-10), an apotosis-related gene, and of calcineurin (Cn) subtype were compared using kidney isografts from BD versus living donors. METHODS: Donors were intubated and mechanically ventilated for 6 hours. Grafts were harvested 6 hours after BD, and at 1, 6, and 24 hours and 5 days after engraftment. Messenger RNA (mRNA) expression was assessed using real-time reverse transcriptase-polymerase chain reaction. RESULTS: Gene expression of IP-10 was up-regulated only among BD donor kidneys, particularly following I/R injury. These changes recovered to baseline levels thereafter. Bcl-2 was suppressed within 6 hours of BD and 1 hour after engraftment. In contrast, Bax in kidneys from BD donors was significantly up-regulated at 6 hours after engraftment. These changes were minimal in the controls. Cn Aalpha and Abeta were decreased in kidneys from BD donors before and within 1 hour after engraftment. However, these differences became insignificant thereafter. CONCLUSIONS: Marked up-regulation of IP-10 may predict the initial graft injury and the onset of delayed graft function. Apoptotic gene changes may lead kidney grafts to a preapoptotic condition and up-regulate renal toxicity caused by Cn inhibitors. This initial antigen-independent donor circumstance may be one risk factor for chronic rejection.

Squamous reepithelialization after circumferential endoscopic mucosal resection of superficial carcinoma arising in Barrett's esophagus.

Recent reports on the results of endoscopic ablation of Barrett's mucosa have been promising, particularly when total mucosal ablation is coupled with aggressive acid-suppression treatment using high-dose proton-pump inhibitor therapy. There is also a considerable literature on reepithelialization after ablative treatments in Barrett's esophagus. This report describes a case of multifocal superficial adenocarcinoma arising in Barrett's mucosa that was successfully treated with total circumferential endoscopic mucosal resection, with a subsequent follow-up of more than 2 years. This is the first report describing the process of squamous reepithelialization after endoscopic mucosal resection in Barrett's esophagus.

Virtual histology of colorectal lesions using laser-scanning confocal microscopy.

BACKGROUND AND STUDY AIMS: Histological examination of gastrointestinal lesions is currently based on light-microscopic examination of thin-slice specimens, with hematoxylin and eosin staining. A study of the use of laser-scanning confocal microscopy (LCM) to obtain immediate microscopic images of untreated specimens for examining colorectal lesions was carried out. A probe-type LCM prototype endomicroscope that can be passed through the working channel of an endoscope has also been developed. MATERIALS AND METHODS: The study materials consisted of colorectal lesions resected either endoscopically or surgically at Showa University Northern Yokohama Hospital. One hundred untreated specimens were examined using LCM. The histopathological findings in the lesions were seven cases of normal colonic mucosa, five hyperplastic polyps, 68 adenomas with low-grade dysplasia, 10 adenomas with high-grade dysplasia, and 10 adenocarcinomas. An argon laser beam with a wavelength of 488 nm was used for the LCM study. Observation of the resected normal colonic mucosa (in vitro) and the rectal mucosa of a healthy volunteer (in vivo) was possible using the endomicroscope. The LCM images for each specimen were compared with the hematoxylin-eosin-stained histopathological cross-sections. RESULTS: The LCM images corresponded well with the conventional hematoxylin-eosin light-microscopic images. The nuclei were not visualized in normal mucosa or hyperplastic polyps. In adenomas with high-grade dysplasia and carcinomas, nuclei were more often visible than in adenomas with low-grade dysplasia. The rate of visualization of nuclei was significantly different ( P < 0.01) between these two groups (60.0 % vs. 10.3 %). In LCM images using endomicroscope, it was possible to recognize the orifices of the colonic glands and goblet cells both in vitro and in vivo. CONCLUSIONS: Laser-scanning confocal microscopy provides immediate images that correspond well with those of hematoxylin-eosin staining. An improved probe-type LCM endomicroscope is being developed which should provide better histological images of colorectal lesions in vivo.

Photocatalytic degradation of gaseous perchloroethylene: products and pathway.

Batch photocatalytic degradation of 1000-ppm gaseous perchloroethylene (PCE) was conducted with UV irradiation such that nearly 100% was decomposed within 10 min. The main intermediate and final product were identified as trichloroacetylchloride (TCAC) and hydrogen chloride (HCl), respectively, and minor ones as dichloroacetic acid (DCAC), monochloroacetic acid (MCAC), carbon tetrachloride, chloroform, and phosgene. More than 90% of Cl- equivalent, i.e., the sum of the chlorine number in PCE, intermediates, and HCl, was compensated for during the time of PCE degradation; a result indicating that no other major chlorinated intermediates are present during the time of PCE degradation. In a similar experiment, 500 ppm of gaseous TCAC degraded into HCl within 3 h without producing DCAC or MCAC, where like PCE, more than 90% of Cl- equivalent, i.e., the sum of the chlorine number in TCAC and HCl, was compensated for during time of TCAC degradation. Accordingly, gaseous PCE is concluded to predominantly follow a degradation pathway of PCE --> TCAC --> HCl.

The small bowel as a source of gastrointestinal blood loss.

The small bowel is a rare but important source of blood loss from the gastrointestinal (GI) tract. In approximately 5% of all patients with GI bleeding, no cause for the bleeding is evident even after an extensive workup. This bleeding is often termed "gastrointestinal bleeding of obscure origin" or "obscure gastrointestinal bleed" (OGIB). Recent advancements in enteroscopy have contributed to a better understanding of the small bowel as a source of bleeding. On average, 27% of patients with OGIB have been shown to have lesions in the small bowel, with common findings including arteriovenous malformations (AVMs) and small bowel tumors. The trend in primary diagnostic workup for obscure GI bleeding or suspected small bowel lesions is shifting toward enteroscopic examination. Availability of an accessory channel now offers the clinician management options such as endoscopic injection therapy, electrocautery, and polypectomy. The "gold standard" for examination of the entire small bowel is intraoperative enteroscopy. A newer technique involving laparascopic assistance may lower the morbidity associated with this examination. Combined hormonal therapy may be an alternative treatment for patients with AVMs or an unknown cause of bleeding after enteroscopic examination.