Appendicitis during the COVID-19 lockdown: results of a multicenter analysis in Germany.

PURPOSE: The COVID-19 pandemic has transformed medical care worldwide. General surgery has been affected in elective procedures, yet the implications for emergency surgery are unclear. The current study analyzes the effect of the COVID-19 lockdown in spring 2020 on appendicitis treatment in Germany. METHODS: Hospitals that provided emergency surgical care during the COVID-19 lockdown were invited to participate. All patients diagnosed with appendicitis during the lockdown period (10 weeks) and, as a comparison group, patients from the same period in 2019 were analyzed. Clinical and laboratory parameters, intraoperative and pathological findings, and postoperative outcomes were analyzed. RESULTS: A total of 1915 appendectomies from 41 surgical departments in Germany were included. Compared to 2019 the number of appendectomies decreased by 13.5% (1.027 to 888, p=0.003) during the first 2020 COVID-19 lockdown. The delay between the onset of symptoms and medical consultation was substantially longer in the COVID-19 risk group and for the elderly. The rate of complicated appendicitis increased (58.2 to 64.4%), while the absolute number of complicated appendicitis decreased from 597 to 569, (p=0.012). The rate of negative appendectomies decreased significantly (6.7 to 4.6%; p=0.012). Overall postoperative morbidity and mortality, however, did not change. CONCLUSION: The COVID-19 lockdown had significant effects on abdominal emergency surgery in Germany. These seem to result from a stricter selection and a longer waiting time between the onset of symptoms and medical consultation for risk patients. However, the standard of emergency surgical care in Germany was maintained.

[Outcomes after Prophylactic Total Gastrectomy for Hereditary Diffuse Gastric Cancer]. / Ergebnisse nach prophylaktischer totaler Gastrektomie bei erblichem diffusem Magenkrebs.

INTRODUCTION: Prophylactic total gastrectomy is the treatment of choice in patients with germline mutation in the CDH1 gene and therefore high risk for hereditary diffuse gastric cancer (HDGC). Minimally invasive techniques have been established in recent years for treatment of gastric cancer. METHODS: We report findings with 12 patients with proven CDH1 mutation who underwent multidisciplinary treatment between 2013 and 3/2018 in our centre for hereditary tumour diseases, followed by prophylactic total gastrectomy in our department. Data were collected in a prospective hereditary tumour database. RESULTS: Open prophylactic total gastrectomy was performed in 5 patients (between 2013 and 2015) and minimally invasive prospective gastrectomy in 7 patients (between 2015 and 2018). The median age of all patients (7 women and 5 men) was 42 (range: 19 - 60) years. The mean operation time was 291 ± 72 minutes (open: 269 ± 70; minimally invasive: 307 ± 75). Perioperative 60-day mortality and anastomotic leakage rate were 0%. In 3 patients, postoperative complications occurred (according to the Clavien-Dindo classification: one each of grades II, IIIa and IVb, respectively), and therefore 25% morbidity. The average postoperative hospital stay was 14.5 ± 6.2 days (open: 16.2 ± 7.9; minimally invasive: 13.3 ± 5.0). In 10 of 12 patients (83%), foci of intramucosal signet ring cell carcinomas were found in the gastric specimen, in 9 patients with multifocal dissemination. There were no cases with advanced carcinomas (≥ pT1b) or lymph node metastases. CONCLUSION: Patients with suspected high risk for hereditary diffuse gastric cancer should be cared for in a multidisciplinary centre for hereditary tumour diseases. Laparoscopic total gastrectomy is a safe and feasible risk-reducing procedure for patients with CDH1 germline mutation. Therefore, in the absence of contraindications and with available surgical expertise, the minimally invasive operation should be the standard procedure for these patients.

Effect of transcutaneous vagus nerve stimulation on muscle activity in the gastrointestinal tract (transVaGa): a prospective clinical trial.

PURPOSE: Postoperative ileus (POI) is a common complication after abdominal surgery. Invasive stimulation of the cervical vagus nerve is known to reduce inflammatory response and ameliorated POI after surgery in a mouse model. However, the transcutaneous vagus nerve stimulation (tVNS) is a possible non-invasive approach. In this clinical study, we aimed to investigate the effect of tVNS on the activation of the stomach muscle in humans. METHODS: Patients requiring open laparotomy were screened for this prospective proof of concept clinical study. After open laparotomy, muscle activity of the stomach was measured by a free running electromyography (EMG) before and during tVNS on the ear. Frequency and amplitude of compound gastric action potentials were the electrophysiological parameters we assessed to reveal the changes in electro motor gastric activity. Gastrin levels as a surrogate marker for vagus nerve activation was analyzed before, 1 and 3 h after tVNS. RESULTS: Fourteen patients were included, no severe adverse events and no medical device related adverse events occurred. tVNS led to significant reduction of action potential frequency and significant elevation of action potential amplitude in the stomach compared to control. Gastrin levels were significantly elevated 3 h after tVNS compared to levels before tVNS. CONCLUSION: Application of tVNS is a safe and feasible procedure during surgical intervention. Our results provide evidence that tVNS activates efferent visceral vagal fibers. Therefore, this low risk and easy to perform method could be useful to prevent postoperative ileus. CLINICAL TRIAL REGISTER NUMBER: DRKS00013340.

[Treatment of HPV-associated Anal Lesions in HIV-positive Patients - Comparison of Surgical Treatment and Topical Therapy with Imiquimod]. / Behandlung HPV-assoziierter analer Läsionen bei HIV-positiven Patienten ­ chirurgische Abtragung vs. topische Therapie mit Imiquimod.

OBJECTIVES: In HIV+-patients, routine proctological assessment is warranted due to the high incidence of human papilloma virus (HPV) infection-related anogenital lesions, such as Condylomata acuminata (C. ac.), anal intraepithelial dysplasia (AIN) and anal cancer. For C. ac. and AIN, surgical resection and topical therapy with imiquimod have been discussed as treatment options. BACKGROUND: In this study, we contrasted surgical resection and topical imiquimod therapy of HPV-associated anal lesions in HIV+-patients, with a focus on healing rates and clinical outcome. We also analysed whether a synergistic treatment effect was detectable. METHODS: This was a retrospective analysis of 97 HIV+ patients who underwent proctological evaluation and treatment over a 10-year period (11/2004 - 11/2015) at our centre. Initial success of surgical treatment, topical imiquimod therapy and the combination of the two strategies were compared. RESULTS: In 53/97 patients (54%), HPV-associated anal disease was diagnosed upon the first visit. In approx. 50% of the patients, the HIV infection was adequately controlled (52 patients with viral load < 40 copies [53.6%]) under cART. The mean age was 41.0 ± 11.6 years. In 7/53 patients with macroscopic C. ac., low-grade and in 18/53 patients high-grade AIN were additionally confirmed. Success rates of surgical resection, imiquimod treatment and the combination of the two were compared. Complete remission of C. ac. and AIN four weeks after treatment was considered a therapeutic success. For C. ac., success rates with imiquimod were 5/25 (20.0%) vs. surgery* 30/57 (52.6%, Mann-Whitney U test p < 0.05) vs. surgery+imiquimod 7/15 (46.7%). For AIN, success rates with imiquimod were 4/24 (16.7%) vs. surgery* 47/83 (56.7%, Mann-Whitney U test p < 0.05) vs. surgery+imiquimod 9/21 (42.8%). In 7/92 (13%) of surgical treatments, complications were reported: four minor and two significant bleeding episodes and one perianal thrombosis. No side effects of imiquimod were documented besides skin irritation. CONCLUSION: Surgery is more effective than topical imiquimod as initial therapy of HPV-related anogenital disease in HIV+-patients. A synergistic effect could not be demonstrated. On this basis, we recommend surgical treatment of C. ac. and AIN in HIV+-patients as first line treatment.

[Late Complications of Permanent Intestinal Stomata]. / Spätkomplikationen permanenter intestinaler Stomata.

INTRODUCTION: Complications following the creation of permanent intestinal ostomies are common and lead to serious problems in the stoma care of affected patients. The aim of this prospective, single-centre follow-up study was to record the rate of late complications in our own patient group and to identify potential risk factors. METHODS: All patients who received a permanent intestinal ostomy in our clinic within the period 2006 - 2016 were included in the study. 50 patients gave their informed consent and participated in our follow-up (14 female [28%], 36 male [72%]). The analysis of stoma-associated complications was performed by review of medical records and a systematic follow-up (standardised questionnaire, clinical examination, and ultrasound of the abdominal wall). RESULTS: Indications included malignancy (n = 27; 54%), anastomotic leakage (n = 10; 20%), acute diverticulitis (n = 7; 14%), IBD (n = 5; 10%) and rarer indications. The top 3 late complications were peristomal skin irritation (n = 25, 50%), parastomal hernia (n = 14; 28%) and prolapse (n = 9; 18%). Acute diverticulitis resulted in increased stomal retraction (p = 0.012). Double-barreled stomata were associated with increased herniation rates (p = 0.044) and prolapse (p = 0.047). Ileostomies were associated with peristomal skin irritation (p = 0.021). Age, sex or emergency stoma creation did not constitute independent risk factors for the development of late complications in our group of patients. CONCLUSION: Professional pre- and postoperative stoma therapy and care includes preoperative marking of a stoma site and structured stoma-specific follow-up by stoma therapists, surgeons and general practitioners, as well as stringent and early treatment of structural complications. This can prevent and mitigate late complications of permanent intestinal stomata. Interestingly, stoma placement was not an independent risk factor for late complications in an emergency situation.

Prophylactic total gastrectomy in the management of hereditary tumor syndromes.

PURPOSE: Germline mutations in several genes confer a relevant lifetime risk of gastric cancer. In this context, an increasing involvement of a surgeon can be seen, mainly with the question of performing a prophylactic operation. METHODS: Patients with hereditary tumor syndromes predisposing for gastric cancer who received care leading to prophylactic total gastrectomy in our Center for Hereditary Tumor Syndromes were analyzed. For each patient, the multidisciplinary decision-making process, the perioperative course, and the histopathologic findings were assessed. Short-term morbidity was evaluated based on the medical reports. RESULTS: The analysis includes nine patients (six female, three male) with a median age of 41.6 (range 23-60) years. Indication for prophylactic total gastrectomy was based on family history and genetic analysis (eight patients with a germline mutation of the CDH1 gene and one patient with a SMAD4 mutation). Removal of the entire gastric mucosa was documented intraoperatively by fresh frozen section examination. Extended (DII) lymphadenectomy was performed in four patients. Histopathologic examination of gastrectomy specimens revealed six patients (6/9, 67 %) with multifocal signet ring cell carcinomas. In our series, prophylactic total gastrectomy was a safe procedure without mortality and low morbidity. CONCLUSIONS: Patients with hereditary syndromes predisposing for gastric cancer should be evaluated for this curative procedure in a specialized center. Further research is necessary, and the implementation of nationwide registers including patients with prophylactic gastrointestinal operations due to hereditary tumor syndrome is advisable.

Impact of Extended Primary Surgery on Suboptimally Operable Patients With Advanced Ovarian Cancer.

OBJECTIVES: Extensive surgical efforts to achieve an optimal debulking (no residual tumor) in primary surgery of ovarian cancer are today's criterion standard in gyneco-oncologic surgery. However, it is controversial whether extensive surgery, including resections of metastases in the upper abdomen and bowel resections, is justifiable in patients with not completely operable lesions. METHODS: All patients who had undergone surgery for ovarian cancer in the years 2002 to 2013 at our institution were viewed (n = 472). We retrospectively identified 278 operations for primary ovarian cancer. Ninety-six (35%) of the 278 patients showed postoperative tumor residuals and were included in this study. RESULTS: Fifty-five (57%) of 96 patients underwent bowel resection, showing significantly higher complication rates (64% vs 39% minor complications, P = 0.017; 31% vs 9.8% severe complications, P = 0.013) compared with patients without bowel resections as well as no improvement in progression-free or overall survival (median overall survival, 19.5 vs 32.9; P = 0.382). Multiple anastomoses (≥2) were associated with higher rates for anastomotic leakage (16.7% vs 2.6%, P = 0.02) and a higher mortality (16.7% vs 0%, P = 0.04) compared with patients with only 1 anastomosis. Extensive surgery of the upper abdomen was not associated with a significant increase in complication rates. CONCLUSIONS: Because of the increased morbidity of bowel resections without any evidence for improvement of survival, we suggest to restrain from further resection of intestines if an optimal debulking seems not feasible after removal of the major tumor bulk.

Risk factors for delayed gastric emptying following distal pancreatectomy.

PURPOSE: Delayed gastric emptying (DGE) is a frequent complication after pancreatoduodenectomy and other types of upper gastrointestinal surgery with published incidences as high as 60 %. The present study examines the incidence of DGE following distal pancreatic resection (DPR). METHODS: Between 2002 and 2014, 100 patients underwent conventional DPR at our department. DGE was classified according to the 2007 International Study Group of Pancreatic Surgery definition. Patients were analyzed regarding severity of DGE, morbidity and mortality, length of hospital stay, and demographic factors. RESULTS: Overall incidence of DGE was 24 %. No difference in age, gender, or other demographic factors was observed in patients with DGE. Perioperative characteristics (splenectomy rate, closure technique of the pancreatic remnant, operation time, blood loss and transfusion, ICU, ASA score) were comparable. Major complications were associated with DGE (11/24 patients (46 %) vs. 19/76 patients (25 %) without DGE) and the rate of pancreatic fistula was significantly higher in the group of patients with DGE (14/24 patients (58 %) vs. 27/76 patients (36 %), P = 0.047). In multivariate analysis, a periampullary malignancy was shown to be a significant factor for DGE development. DGE significantly prolonged hospital stay (14 vs. 22 days). CONCLUSIONS: DGE is a substantial complication not only after pancreatoduodenectomy, but it also occurs frequently after DPR. Prevention of pancreatic fistula might reduce its incidence, especially in patients with malign pathology.

Oral CPSI-2364 treatment prevents postoperative ileus in swine without impairment of anastomotic healing.

BACKGROUND: Postoperative ileus (POI) is an iatrogenic complication of abdominal surgery, mediated by a severe inflammation of the muscularis externa (ME). We demonstrated that orally applicated CPSI-2364 prevents POI in rodents by blockade of p38 MAPK pathway and abrogation of NO production in macrophages. In the present experimental swine study we compared the effect of orally and intravenously administered CPSI-2364 on POI and examined CPSI-2364 effect on anastomotic healing. METHODS: CPSI-2364 was administered preoperatively via oral or intravenous route. POI was induced by intestinal manipulation of the small bowel. ME specimens were examined by quantitative PCR for CCL2 chemokine gene expression and myeloperoxidase activity. Functional analyzes included measurement of ileal smooth-muscle ex vivo contractility, in vivo intestinal and colonic transit. Furthermore, anastomotic healing of a rectorectostomy after CPSI-2364 treatment was assessed by perianastomotic hydroxyproline concentration, a histochemically evaluated healing score and anastomotic bursting pressure (ABP). RESULTS: CPSI-2364 abolished inflammation of the ME and improved postoperative smooth muscle contractility and intestinal transit independently of its application route. Hydroxyproline concentration and ABP measurement revealed no wound healing disturbances after oral or intravenous CPSI-2364 treatment whereas histological scoring demonstrated delayed anastomotic healing after intravenous treatment. CONCLUSION: CPSI-2364 effectively prevents POI in swine independently of its application route. Impairment of anastomotic healing could be observed after intravenous but not oral preoperative CPSI-2364 treatment. Subsumed, an oral preoperative administration of CPSI-2364 appears to be a safe and efficient strategy for prophylaxis of POI.

Liver sinusoidal endothelial cells contribute to CD8 T cell tolerance toward circulating carcinoembryonic antigen in mice.

UNLABELLED: Immunity against cancer is impeded by local mechanisms promoting development of tumor-specific T cell tolerance, such as regulatory T cells, myeloid-derived suppressor cells, or immunosuppressive factors in the tumor microenvironment. The release of soluble antigens, such as carcinoembryonic antigen (CEA) from colorectal carcinoma (CRC) cells, has been investigated for diagnostic purposes, but not for its immunological consequences. Here, we address the question of whether soluble CEA influences tumor-specific immunity. Mice were injected with soluble CEA protein, and CEA-specific CD8 T cells were analyzed for their phenotype and functionality by means of restimulation ex vivo or antitumor efficacy in vivo. We furthermore characterized the CD8 T cell population in peripheral blood mononuclear cell (PBMCs) from healthy donors and colorectal carcinoma patients. In mice, circulating CEA was preferentially taken up in a mannose receptor-dependent manner and cross-presented by liver sinusoidal endothelial cells, but not dendritic cells, to CD8 T cells. Such systemically circulating CEA promoted tolerization of CEA-specific CD8 T cells in the endogenous T cell repertoire through the coinhibitory molecule B7H1. These CD8 T cells were not deleted but were rendered nonresponsive to antigen-specific stimulation and failed to control growth of CEA-expressing tumor cells. These nonresponsive CD8 T cells were phenotypically similar to central memory T cells being CD44(high) CD62L(high) CD25(neg) . We found T cells with a similar phenotype in PBMCs of healthy donors and at increased frequency also in patients with colorectal carcinoma. CONCLUSION: Our results provide evidence for the existence of an unrecognized tumor immune escape involving cross-presentation of systemically circulating tumor antigens that may influence immunotherapy of cancer.

Colonic anastomotic healing in the context of altered macrophage function and endotoxemia.

PURPOSE: Prevention of perioperative activation of intestinal muscularis macrophages is a promising intervention to avoid post-traumatic gastrointestinal tract dysfunction. However, impaired macrophage function could have deleterious consequences on anastomotic healing, especially in complications aggravating the healing process itself, such as infectious problems either as preexisting local inflammation or infection (e.g., complicated diverticulitis) or endotoxemia due to early postoperative infections (e.g., pneumonia). Aim of this study was to investigate colonic anastomotic healing in macrophage-depleted mice in the presence of endotoxemia. METHODS: Colonic anastomoses were performed, and mice were randomized into six groups (wild type; wild type with endotoxemia; pharmacological depletion of macrophages; pharmacological depletion with endotoxemia; genetically conditioned within the gut muscularis macrophage-deficient osteopetrotic mice; osteopetrotic mice with endotoxemia). Anastomotic tissues were removed 2, 5, and 10 days after surgery and used for functional, histological, biochemical, and molecular investigations. RESULTS: After pharmacological pretreatment, an almost complete depletion of macrophages was found in the muscularis up to 24 h postoperatively. Bursting pressure was significantly lower than 10 days after anastomotic procedure in osteopetrotic mice during endotoxemia, in marked contrast to transient pharmacologically macrophage-depleted mice. Pharmacological depletion during endotoxemia did not affect hydroxyproline concentration. Finally, in osteopetrotic mice during endotoxemia, collagen-3 expression was significantly lower compared to controls. CONCLUSIONS: In our current model, we demonstrate that perioperative pharmacological macrophage depletion and inactivation transiently diminishes muscularis macrophages and does not affect intestinal anastomotic healing in the presence of endotoxemia. However, a long-lasting macrophage absence or dysfunction impairs anastomotic healing and could be a risk factor for postoperative anastomotic leakage.

Long Term Outcome After Open Abdomen Treatment: Function and Quality of Life.

Background: Open abdomen treatment (OAT) is widely accepted to manage severe abdominal conditions such as peritonitis and abdominal compartment syndrome but can be associated with high morbidity and mortality. The main risks in OAT are (1) entero-atmospheric fistula (EAF), (2) failure of primary fascial closure, and (3) incisional hernias. In this study, we assessed the long-term functional outcome after OAT to understand which factors impacted most on quality of life (QoL)/daily living activities and the natural course after OAT. Materials and Methods: After a retrospective analysis of 165 consecutive OAT patients over a period of 10 years (2002-2012) with over 65 clinical parameters that had been performed at our center (1), we initiated a prospective structured follow-up approach. All survivors were invited for a clinical follow-up. Forty complete datasets including clinical and social follow-up with SF-36 scores were available for full analysis. Results: The patients were dominantly male (75%) with a median age of 52 years. Primary fascial closure (PC) was achieved in 9/40 (23%), while in 77% a planned ventral hernia (PVH) approach was followed. A total of 3/4 of the PVH patients underwent a secondary-stage abdominal wall reconstruction (SSR), but 2/3 of these reconstructed patients developed recurrent hernias. Fifty-five percent of the patients with PC developed an incisional hernia, while 20% of all patients developed significant scarring (Vancouver Scar Score >8). Scar pain was described by 15% of the patients as "moderate" [Visual Analog Scale (VAS) 4-6] and by 10% as "severe" (VAS > 7). While hernia presence, PC or PVH, and scarring showed no impact on QoL, male sex and especially EAF formation significantly reduced QoL. Discussion: Despite many advantages, OAT was associated with relevant mortality and morbidity, especially in the early era before the implementation of a structured concept at our center. Follow-up revealed that hernia incidence after OAT and secondary reconstruction were high and that 25% of patients qualifying for a secondary reconstruction either did not want surgery or were unfit. Sex and EAF formation impacted significantly on QoL, which was lower than in the general population. With regard to hernia incidence, new strategies such as prophylactic mesh implantation upon fascial closure should be discussed analogous to other major abdominal procedures.

Inhibition of p38 mitogen-activated protein kinase pathway as prophylaxis of postoperative ileus in mice.

BACKGROUND & AIMS: Postoperative ileus, an iatrogenic complication of abdominal surgery, is mediated by severe inflammation of the tunica muscularis. Macrophages that reside in the muscularis have important roles in initiating the inflammation. We investigated whether activation of the p38 mitogen-activated protein kinase (MAPK) and stress-activated protein kinase is involved in the genesis of postoperative ileus, and whether p38-MAPK inhibition by the macrophage-specific inhibitor semapimod prevents intestinal dysmotility. METHODS: Postoperative ileus was induced by intestinal manipulation of the small bowel in mice. Protein kinase phosphorylation was assessed by immunoblotting of muscularis externa preparations. Proinflammatory gene expression was quantified by real-time polymerase chain reaction. Myeloperoxidase histochemistry for neutrophils was performed in jejunal segments. Nitric oxide production was measured by Griess reaction in smooth-muscle organ culture supernatants. Jejunal contractility was assessed within an organ bath setup. Intestinal motility was analyzed by gastrointestinal and colonic transit measurements. RESULTS: High levels of p38-MAPK and stress-activated protein kinase phosphorylation were observed immediately after intestinal manipulation. Semapimod treatment led to a significant decrease of p38-MAPK phosphorylation in macrophages; proinflammatory gene expression of macrophage inflammatory protein-1alpha, interleukin-6, monocyte chemoattractant protein-1, and intercellular adhesion molecule-1; and neutrophil infiltration. Furthermore, semapimod completely abrogated nitric oxide production within the tunica muscularis. Subsequently, semapimod prevented the suppression of smooth muscle contractility and small intestinal and colonic motility after intestinal manipulation. CONCLUSION: A single preoperative semapimod administration prevents intestinal macrophage activation and subsequent gastrointestinal dysmotility induced by abdominal surgery. Semapimod inhibits p38-MAPK and nitric oxide production in macrophages, making it a promising strategy for prophylaxis of postoperative ileus.

The effect of sealing with a fixed combination of collagen matrix-bound coagulation factors on the healing of colonic anastomoses in experimental high-risk mice models.

PURPOSE: Experimental and clinical studies on the sealing of colorectal anastomoses in order to reduce the rate of leakage have previously been performed with divergent results. However, comparatively few studies have been performed on anastomotic healing using a fibrin glue-coated patch. The aim of this experimental basic scientific study in mice was to investigate the effect of fibrin glue-coated collagen patches on the healing process of colonic anastomoses in situations of adverse healing process (technical deficiency and peritonitis). METHODS: Colonic anastomoses were carried out in 206 mice and randomized into six groups (I: complete anastomoses, II: sealed complete anastomoses, III: incomplete anastomoses, IV: sealed incomplete anastomoses, V: complete anastomoses in the presence of bacterial peritonitis, VI: sealed complete anastomoses in the presence of bacterial peritonitis). Tissues from the anastomoses were removed and used for functional, histochemical, molecular, and biochemical investigations. RESULTS: The evaluation of postoperative course data revealed the beneficial effect of additional sealing with a fixed combination of collagen matrix-bound coagulation factors I and IIa (Tachosil(®), Nycomed Austria, Linz) in high-risk experimental anastomotic healing. Sealing incomplete anastomoses resulted in significantly lower lethality and leakage rates, as well as significantly higher bursting pressure values and histopathologic scores. Collagen 1 and 3 expressions and hydroxyproline concentrations are greatly increased with additional sealing in all high-risk anastomoses. CONCLUSIONS: In our current model, we demonstrate that additionally sealing high-risk experimental colonic anastomoses provides a positive effect on the healing process. The effect on the molecular level in particular seems to be essential and requires further experimental studies to evaluate the mechanism.

Investigation of Hydrogen Embrittlement Susceptibility and Fracture Toughness Drop after in situ Hydrogen Cathodic Charging for an X65 Pipeline Steel.

The present research focuses on the investigation of an in situ hydrogen charging effect during Crack Tip Opening Displacement testing (CTOD) on the fracture toughness properties of X65 pipeline steel. This grade of steel belongs to the broader category of High Strength Low Alloy Steels (HSLA), and its microstructure consists of equiaxed ferritic and bainitic grains with a low volume fraction of degenerated pearlite islands. The studied X65 steel specimens were extracted from pipes with 19.15 mm wall thickness. The fracture toughness parameters were determined after imposing the fatigue pre-cracked specimens on air, on a specific electrolytic cell under a slow strain rate bending loading (according to ASTM G147-98, BS7448, and ISO12135 standards). Concerning the results of this study, in the first phase the hydrogen cations' penetration depth, the diffusion coefficient of molecular and atomic hydrogen, and the surficial density of blisters were determined. Next, the characteristic parameters related to fracture toughness (such as J, KQ, CTODel, CTODpl) were calculated by the aid of the Force-Crack Mouth Open Displacement curves and the relevant analytical equations.

Structured Reporting of Solid and Cystic Pancreatic Lesions in CT and MRI: Consensus-Based Structured Report Templates of the German Society of Radiology (DRG). / Strukturierte Befundung von soliden und zystischen Pankreasläsionen im CT und MRT: Konsensus-basierte Befundvorlagen der Deutschen Röntgengesellschaft (DRG).

BACKGROUND: Radiological reports of pancreatic lesions are currently widely formulated as free texts. However, for optimal characterization, staging and operation planning, a wide range of information is required but is sometimes not captured comprehensively. Structured reporting offers the potential for improvement in terms of completeness, reproducibility and clarity of interdisciplinary communication. METHOD: Interdisciplinary consensus finding of structured report templates for solid and cystic pancreatic tumors in computed tomography (CT) and magnetic resonance imaging (MRI) with representatives of the German Society of Radiology (DRG), German Society for General and Visceral Surgery (DGAV), working group Oncological Imaging (ABO) of the German Cancer Society (DKG) and other radiologists, oncologists and surgeons. RESULTS: Among experts in the field of pancreatic imaging, oncology and pancreatic surgery, as well as in a public online survey, structured report templates were developed by consensus. These templates are available on the DRG homepage under www.befundung.drg.de and will be regularly revised to the current state of scientific knowledge by the participating specialist societies and responsible working groups. CONCLUSION: This article presents structured report templates for solid and cystic pancreatic tumors to improve clinical staging (cTNM, ycTNM) in everyday radiology. KEY POINTS: · Structured report templates offer the potential of optimized radiological reporting with regard to completeness, reproducibility and differential diagnosis.. · This article presents consensus-based, structured reports for solid and cystic pancreatic lesions in CT and MRI.. · These structured reports are available open source on the homepage of the German Society of Radiology (DRG) under www.befundung.drg.de.. CITATION FORMAT: · Persigehl T, Baumhauer M, Baeßler B et al. Structured Reporting of Solid and Cystic Pancreatic Lesions in CT and MRI: Consensus-Based Structured Report Templates of the German Society of Radiology (DRG). Fortschr Röntgenstr 2020; 192: 641 - 655.

Impaired intestinal wound healing in Fhl2-deficient mice is due to disturbed collagen metabolism.

Four and one half LIM domain protein FHL2 participates in many cellular processes involved in tissue repair such as regulation of gene expression, cytoarchitecture, cell adhesion, migration and signal transduction. The repair process after wounding is initiated by the release of peptides and bioactive lipids. These molecules induce synthesis and deposition of a provisional extracellular matrix. We showed previously that sphingosine-1-phosphate (S1P) triggers a signal transduction cascade mediating nuclear translocation of FHL2 in response to activation of the RhoA GTPase. Our present study shows that FHL2 is an important signal transducer influencing the outcome of intestinal anastomotic healing. Early wound healing is accompanied by reconstitution and remodelling of the extracellular matrix and collagen is primarily responsible for wound strength. Our results show that impaired intestinal wound healing in Fhl2-deficient mice is due to disturbed collagen III metabolism. Impaired collagen III synthesis reduced the mechanical stability of the anastomoses and led to lower bursting pressure in Fhl2-deficient mice after surgery. Our data confirm that FHL2 is an important factor regulating collagen expression in the early phase of wound healing, and thereby is critically involved in the physiologic process of anastomosis healing after bowel surgery and thus may represent a new therapeutic target.

Non-invasive transcutaneous auricular vagus nerve stimulation prevents postoperative ileus and endotoxemia in mice.

BACKGROUND: The cholinergic anti-inflammatory pathway comprises the perception of peripheral inflammation by afferent sensory neurons and reflex activation of efferent vagus nerve activity to regulate inflammation. Activation of this pathway was shown to reduce the inflammatory response and improve outcome of postoperative ileus (POI) and sepsis in rodents. Herein, we tested if a non-invasive auricular electrical transcutaneous vagus nerve stimulation (tVNS) affects inflammation in models of POI or endotoxemia. METHODS: Mice underwent tVNS or sham stimulation before and after induction of either POI by intestinal manipulation (IM) or endotoxemia by lipopolysaccharide administration. Some animals underwent a preoperative right cervical vagotomy. Neuronal activation of the solitary tract nucleus (NTS) and the dorsal motor nucleus of the vagus nerve (DMV) were analyzed by immunohistological detection of c-fos+ cells. Gene and protein expression of IL-6, MCP-1, IL-1ß as well as leukocyte infiltration and gastrointestinal transit were analyzed at different time points after IM. IL-6, TNFα, and IL-1ß serum levels were analyzed 3 hours after lipopolysaccharide administration. RESULTS: tVNS activated the NTS and DMV and reduced intestinal cytokine expression, reduced leukocyte recruitment to the manipulated intestine segment, and improved gastrointestinal transit after IM. Endotoxemia-induced IL-6 and TNF-α release was also reduced by tVNS. The protective effects of tVNS on POI and endotoxemia were abrogated by vagotomy. CONCLUSION: tVNS prevents intestinal and systemic inflammation. Activation of the DMV indicates an afferent to efferent central circuitry of the tVNS stimulation and the beneficial effects of tVNS depend on an intact vagus nerve. tVNS may become a non-invasive approach for treatment of POI.

Acute rejection and the muscularis propria after intestinal transplantation: the alloresponse, inflammation, and smooth muscle function.

BACKGROUND: It has been shown that in transplantation the intestinal muscularis may act as an immunologically active layer via the activation of resident macrophages and the recruitment of leukocytes. Thus we hypothesized that inflammation within the intestinal muscularis is involved in the promotion of acute rejection in intestinal allografts and that this causes smooth muscle dysfunction. METHODS: Orthotopic allogenic and small bowel transplantation (Brown-Norway rats-Lewis rats) was performed without immunosuppression. Animals were sacrificed 1, 4, and 7 days after small bowel transplantation. Isogenic transplanted grafts (Brown-Norway rats-Brown-Norway rats) as well as nontransplanted bowel served as controls. Mediator mRNA expression was determined by real-time reverse-transcriptase polymerase chain reaction. Leukocyte infiltration was evaluated in muscularis whole mounts by immunohistochemistry. Apoptosis was evaluated by TdT-mediated dUTP-X nick end labeling assay. Contractility was assessed in a standard organ bath under bethanechol stimulation. Statistical analysis was performed using a Student's t test and one-way analysis of variance. RESULTS: Transplanted animals showed a significant early inflammatory response within the graft muscularis because of reperfusion injury. Only allogenic transplanted animals exhibited a significant second molecular inflammatory peak in the muscularis during rejection (mRNA induction for interleukin (IL)-6, intercellular adhesion molecule-1, monocyte chemoattractant protein (MCP)-1, interferon-gamma, IL-2, tumor necrosis factor-alpha, IL-10, inducible nitric oxide synthase). These findings were associated with significant leukocyte infiltration within the muscularis, increasing apoptotic cells and massive impairment of smooth muscle contractile activity by 78%. CONCLUSIONS: The data shows that transplantation results in an early and temporary inflammatory response within the intestinal graft muscularis, that is reactivated and intensified during acute allograft rejection. The immunoreaction within the intestinal muscularis leads to intestinal allograft smooth muscle dysfunction.

Inducible nitric oxide synthase expression in the intestinal muscularis mediates severe smooth muscle dysfunction during acute rejection in allogenic rodent small bowel transplantation.

BACKGROUND: Acute rejection in small bowel transplantation is associated with dysmotility. Therefore, host and organ not only face the threat of destructive immunological processes but also the risk of bacterial translocation, endotoxemia, and systemic inflammatory response syndrome. We hypothesized that dysmotility during acute rejection is based on an alloreactive leukocyte infiltrate and coexpression of the kinetically active mediator inducible nitric oxide synthase (iNOS) in the muscularis propria. MATERIALS AND METHODS: Allogenic and isogenic rat small bowel transplantation (SBTx; Brown Norway [BN] to Lewis and BN to BN) was performed without immunosuppression. Animals were sacrificed 4 and 7 d after SBTx. Leukocyte infiltration and iNOS protein was investigated by immunohistochemistry and immunohistology. Real-time reverse transcription polymer chain reaction was used to detect iNOS expression. Griess reaction was used to evaluate NO production. Spontaneous, bethanechol-stimulated, and L-N(6)-(1-iminoethyl)-L-Lysin-blocked jejunal circular muscle contractions were measured in a standard organ bath in vitro. RESULTS: On d 7 after SBTx, allogenic transplanted animals showed significant infiltration with ED-1- and ED-2-positive monocytes and macrophages within the muscularis parallel to the manifestation of acute rejection. Additionally, immunohistochemistry localized iNOS protein in leukocytes within the muscularis. Reverse transcription polymer chain reaction showed a significant increase in iNOS mRNA expression (460-fold) in allogenic transplanted muscularis compared to isogenic transplanted muscularis (2.5-fold). Compared to controls, allogenic grafts showed a 73% decrease in smooth muscle contractility, while isogenic grafts showed only an 8% decrease of contractility on d 7. L-N(6)-(1-iminoethyl)-L-Lysin application in vitro significantly improved muscle contractility and decreased NO production. CONCLUSION: The data show that inflammation associated iNOS expression in the intestinal graft muscularis is involved in motoric graft dysfunction during acute rejection.