SARS-CoV-2 Cell Entry Depends on ACE2 and TMPRSS2 and Is Blocked by a Clinically Proven Protease Inhibitor.

The recent emergence of the novel, pathogenic SARS-coronavirus 2 (SARS-CoV-2) in China and its rapid national and international spread pose a global health emergency. Cell entry of coronaviruses depends on binding of the viral spike (S) proteins to cellular receptors and on S protein priming by host cell proteases. Unravelling which cellular factors are used by SARS-CoV-2 for entry might provide insights into viral transmission and reveal therapeutic targets. Here, we demonstrate that SARS-CoV-2 uses the SARS-CoV receptor ACE2 for entry and the serine protease TMPRSS2 for S protein priming. A TMPRSS2 inhibitor approved for clinical use blocked entry and might constitute a treatment option. Finally, we show that the sera from convalescent SARS patients cross-neutralized SARS-2-S-driven entry. Our results reveal important commonalities between SARS-CoV-2 and SARS-CoV infection and identify a potential target for antiviral intervention.

Endoscopic Vacuum Therapy for Left-Sided Colorectal Anastomotic Leak Without Fecal Diversion.

BACKGROUND: Endoscopic vacuum therapy for the treatment of rectal anastomotic leak has been shown to be effective and safe. The majority of patients are treated after fecal diversion to avoid further septic complications. OBJECTIVE: To report the effectiveness of endoscopic vacuum therapy for rectal anastomotic leak without diversion compared to secondary stoma creation. DESIGN: Retrospective cohort analysis. SETTINGS: University hospital, single-center. PATIENTS: Patients undergoing sigmoid or rectal resection without fecal diversion during primary surgery who were treated with endoscopic vacuum therapy for clinically relevant anastomotic leak. MAIN OUTCOME MEASURES: Treatment success (sepsis control, granulation and closure of the leak cavity, and no subsequent interventional or surgical procedure required); treatment duration; complications associated with endoscopic vacuum therapy; outpatient treatment; and restoration of intestinal continuity in diverted patients. RESULTS: Fifty-seven patients were included. In 20 patients (35%), endoscopic vacuum therapy was initiated without secondary diversion since the leak was extraperitoneal, and the sponge could be placed into the leak cavity with an adequate seal toward the lumen. In 18 patients (90%), this approach was successful. None of these patients required subsequent diversion in the further course of their disease. In two patients, secondary diversion was necessary due to treatment failure. Balloon dilatation for luminal stenosis was required in two patients. When comparing patient and treatment characteristics of patients with and without a stoma, including treatment success and duration, no significant differences were found. Restoration of intestinal continuity was achieved in 69% of diverted patients. LIMITATIONS: Unrandomized, retrospective study design; confounding factors of treatment assignment; low patient numbers and short follow-up of diverted patients; and low statistical power. CONCLUSION: In this single-institution study, endoscopic vacuum therapy for rectal anastomotic leak was successful in 90% of patients without diversion with regard to sepsis control, granulation of the leak cavity, avoidance of surgery, and long-term stoma-free survival. See Video Abstract at http://links.lww.com/DCR/B737.TERAPIA ENDOSCÓPICA POR ASPIRACIÓN AL VACÍO EN CASOS DE FUGA ANASTOMÓTICA RECTO-CÓLICA IZQUIERDA SIN OSTOMÍA DE PROTECCIÓNANTECEDENTES:Se ha demostrado que la terapia endoscópica por aspiración al vacío en casos de fuga anastomótica recto-cólica izquierda en el tratamiento de la fuga anastomótica rectal es eficaz y segura. La mayoría de los casos beneficiaron del tratamiento después de la confeción de un ostomía de protección para evitar más complicaciones sépticas.OBJETIVO:Demostrar la efectividad de la terapia endoscópica por aspiración al vacío en casos de fuga anastomótica recto-cólica izquierda sin ostomía de protección comparada con los casos que tuvieron la creación de una ostomía secundaria.DISEÑO:Análisis de cohortes de tipo retrospectivo.AJUSTE:Hospital universitario, unicéntrico.PACIENTES:Aquellos pacientes sometidos a una resección sigmoidea o rectal sin ostomía de protección durante una cirugía primaria, y que fueron tratados con terapia endoscópica por aspiración al vacío en caso de fuga anastomótica clínicamente relevante.PRINCIPALES MEDIDAS DE RESULTADO:Tratamiento exitoso (control de la sepsis, granulación y cierre de la cavidad de la fuga, sin requerir procedimiento quirúrgico o intervención ulteterior); duración del tratamiento; complicaciones asociadas con la terapia endoscópica por aspiración al vacío; tratamiento ambulatorio; restablecimiento de la continuidad intestinal en los pacientes portadores de ostomía.RESULTADOS:Se incluyeron 57 pacientes. En 20 pacientes (35%), se inició la terapia endoscópica por aspiración al vacío sin derivación secundaria, ya que la fuga era extraperitoneal y la esponja podía colocarse en la cavidad de la fuga con un sellado adecuado hacia el lumen. En 18 pacientes (90%), este enfoque fue exitoso. Ninguno de estos pacientes requirió una derivación posterior durante la evolución de la enfermedad. En dos pacientes, fue necesaria una derivación secundaria debido al fracaso del tratamiento. Se requirió dilatación con balón por estenosis luminal en dos pacientes. Al comparar las características de los pacientes y del tratamiento con y sin ostomía, incluido el éxito y la duración del tratamiento, no se encontraron diferencias significativas. El restablecimiento de la continuidad intestinal se logró en el 69% de los pacientes derivados.LIMITACIONES:Diseño de estudio retrospectivo no aleatorio; factores de confusión en la asignación del tratamiento; escaso número de pacientes y seguimiento a corto plazo de los pacientes ostomizados; bajo poder estadístico.CONCLUSIÓN:En este estudio de una sola institución, la terapia al vacío por vía endoscópica en casos de fuga anastomótica rectal fue exitosa en el 90% de los pacientes sin derivación con respecto al control de la sepsis, granulación de la cavidad de la fuga, como se evitó la cirugía y la sobrevida sin ostomía a largo plazo. Consulte Video Resumen en http://links.lww.com/DCR/B737. (Traducción-Dr. Xavier Delgadillo).

It is not NOD2 - genetic and clinical risk factors for postoperative complications following ileocolic resection in Crohn's disease.

PURPOSE: To evaluate the role of the nucleotide oligomerization domain 2 (NOD2) mutation status and other risk factors for the incidence of postoperative complications after ileocolic resection for Crohn's disease (CD). METHODS: Data of 138 patients consecutively undergoing ileocolic resection for CD at a tertiary academic referral center were retrospectively analyzed including single nucleotide polymorphism (SNP) data of the NOD2 gene. Uni- and multivariate regression analysis was performed to identify factors associated with increased risk of severe postoperative complications. RESULTS: From 114 patients (83%), the NOD2 mutation status was available. Of these, 60 (53%) had a NOD2 wildtype, whereas eleven (10%) were homozygous for the high risk p.Leu1007fsX1008 (rs2066847) variant. Major postoperative complications occurred in 28 patients (20%). Twenty-seven of these (96%) were intraabdominal septic complications such as anastomotic leakage or abscess. Male gender (P = 0.029; OR 3.052, the duration of CD (time [months] from initial diagnosis of CD to surgery; P = 0.001; OR 1.009), previous abdominal surgery for CD (P = 0.017; OR 3.49), and the presence of enteric fistulas (P = 0.023; OR 3.21) were identified as independent risk factors for major postoperative complications. Homozygosity for the NOD2 high-risk variant p.Leu1007fsX1008 did not show increased postoperative morbidity in the short and long-term outcome. CONCLUSIONS: We could detect independent risk factors for major postoperative complications after ileocolic resection for Crohn's disease. However, patients with the high-risk variant p.Leu1007fsX1008 of the NOD2 gene did not show increased postoperative morbidity.

Nelfinavir and Its Active Metabolite M8 Are Partial Agonists and Competitive Antagonists of the Human Pregnane X Receptor.

The HIV protease inhibitor nelfinavir is currently being analyzed for repurposing as an anticancer drug for many different cancers because it exerts manifold off-target protein interactions, finally resulting in cancer cell death. Xenosensing pregnane X receptor (PXR), which also participates in the control of cancer cell proliferation and apoptosis, was previously shown to be activated by nelfinavir; however, the exact molecular mechanism is still unknown. The present study addresses the effects of nelfinavir and its major and pharmacologically active metabolite nelfinavir hydroxy-tert-butylamide (M8) on PXR to elucidate the underlying molecular mechanism. Molecular docking suggested direct binding to the PXR ligand-binding domain, which was confirmed experimentally by limited proteolytic digestion and competitive ligand-binding assays. Concentration-response analyses using cellular transactivation assays identified nelfinavir and M8 as partial agonists with EC50 values of 0.9 and 7.3 µM and competitive antagonists of rifampin-dependent induction with IC50 values of 7.5 and 25.3 µM, respectively. Antagonism exclusively resulted from binding into the PXR ligand-binding pocket. Impaired coactivator recruitment by nelfinavir as compared with the full agonist rifampin proved to be the underlying mechanism of both effects on PXR. Physiologic relevance of nelfinavir-dependent modulation of PXR activity was investigated in respectively treated primary human hepatocytes, which showed differential induction of PXR target genes and antagonism of rifampin-induced ABCB1 and CYP3A4 gene expression. In conclusion, we elucidate here the molecular mechanism of nelfinavir interaction with PXR. It is hypothesized that modulation of PXR activity may impact the anticancer effects of nelfinavir. SIGNIFICANCE STATEMENT: Nelfinavir, which is being investigated for repurposing as an anticancer medication, is shown here to directly bind to human pregnane X receptor (PXR) and thereby act as a partial agonist and competitive antagonist. Its major metabolite nelfinavir hydroxy-tert-butylamide exerts the same effects, which are based on impaired coactivator recruitment. Nelfinavir anticancer activity may involve modulation of PXR, which itself is discussed as a therapeutic target in cancer therapy and for the reversal of chemoresistance.

Kupffer cell activation by different microbial lysates: Toll-like receptor-2 plays pivotal role on thromboxane A2 production in mice and humans.

Thromboxane (TX) A2 has been identified as an important intrahepatic vasoconstrictor upon Kupffer cell (KC) activation during infections such as spontaneous bacterial peritonitis (SBP). The study aimed to investigate the role of TLRs in the TXA2 increase in liver nonparenchymal cells and their related mechanisms. Here, we identified TLR-2 as a common pathway for different microbials: microbial lysates including Gram-positive bacteria, Gram-negative bacteria, and fungi all increased TXA2 secretion via activation of TLR-2 in human KCs, accompanied by increased expression and phosphorylation of Myd88-related pathway. Of all TLR agonists, only TLR-1, -2, and -4 agonists increased TXA2 in human KCs. These results were further confirmed by mouse liver nonparenchymal cells. Comparing the effects of TLR-1, -2, and -4 antagonists, only TLR-2 antagonist showed inhibitory effects with all tested microbial lysates. Pretreatment with TLR-2 antagonist in human KCs blocked the secretion of IL-10, CXCL-10, TNF-α, and IL-6 induced by Gram-positive and Gram-negative bacterial stimulation. IL-23 and IL-1ß were only induced by Gram-negative bacteria. Thus, TLR-2 might be a potential marker and an attractive target for future treatment of patients with SBP. In addition, IL-23 and IL-1ß might distinguish early between Gram-positive and Gram-negative SBP.

Chances, challenges and outcomes of patients with complex bilobar colorectal liver metastases approached by a combined multimodal therapy with liver resection and local ablative therapy.

BACKGROUND AND OBJECTIVES: In treatment of colorectal liver metastases (CRC-LM), liver surgery combined with systemic therapies and local ablation (LAT) allows improved survival. This study aims at the outcomes of patients with complex bilobar CRC-LM who were intended to undergo multimodal therapy with liver resection and LAT. METHODS: Forty-three CRC-LM patients with recommendation for multimodal treament were extracted from 5878 tumor board decisions between 2014 and 2017. Outcome variables included patient survival, as well as completion of hepatic clearance. Prognostic factors were identified by correlation and a Cox proportional hazards model. RESULTS: Out of 43 patients only 23 achieved complete clearance of CRC-LM. One- and 3-year overall survival of patients with cleared liver disease was 100% and 91.7%, respectively, as compared to 83.8% and 12.1%. Incomplete hepatic clearance was the strongest independent risk factor for overall survival (hazards ratio [HR], 5.86; p = .009). Risk factors for incomplete clearance were higher age (r = .34; p = .026), comorbidities (r = .40; p = .008), major complications (r = .34; p = .024), and prolonged intensive care unit stay (r = .41; p = .017). CONCLUSION: Completion of hepatic clearance is crucial to achieve long-term survival in patients with complex bilobar CRC-LM. Careful patient selection and treatment planning should avoid treatment failure before completing the intended therapy plan when multimodal treatments are planned.

Endoscopic vacuum therapy for in- and outpatient treatment of colorectal defects.

BACKGROUND: Evidence for endoscopic vacuum therapy (EVT) for colorectal defects is still based on small patient series from various institutions, employing different treatment algorithms and methods. As EVT was invented at our institution 20 years ago, the aim was to report the efficacy and safety of EVT for colorectal defects as well as to analyze factors associated with efficacy, therapy duration, and outpatient treatment. METHODS: Cohort study with analysis of prospectively collected data of patients receiving EVT for colorectal defects at a tertiary referral center in Germany (n = 281). RESULTS: The majority of patients had malignant disease (83%) and an American Society of Anesthesiologists classification of III/IV (81%). Most frequent indications for EVT were anastomotic leakage after sigmoid or rectal resection (67%) followed by rectal stump leakage (20%). EVT was successful in 256 out of 281 patients (91%). EVT following multi-visceral resection (P = 0.037) and recent surgical revision after primary surgery (P = 0.009) were risk factors for EVT failure. EVT-associated adverse events occurred in 27 patients (10%). Median treatment duration was 25 days. Previous chemo-radiation (P = 0.006) was associated with a significant longer duration of EVT. Outpatient treatment was conducted in 49% of patients with a median hospital stay reduction of 15 days and 98% treatment success. Younger patient age (P = 0.044) was associated with the possibility of outpatient treatment. Restoration of intestinal continuity was achieved in 60% of patients where technically possible with a 12-month rate of 52%. CONCLUSIONS: In patients with colorectal defects, EVT appears to be a safe and effective, minimally invasive option for in- and outpatient treatment.

Endoscopic vacuum therapy for treatment of rectal stump leakage.

BACKGROUND: Symptomatic rectal stump leakage (RSL) is a serious complication after discontinuity resection and requires immediate surgical, interventional, or endoscopic therapy. Re-operations are associated with high morbidity and mortality in these mostly very ill patients. Endoscopic vacuum therapy (EVT) has been established for management of anastomotic leakage; however, its effectiveness for RSL treatment has not been analyzed in detail yet. METHODS: A retrospective analysis of patients treated with EVT for RSL between 2001 and 2018 analyzing factors predicting therapy success and duration was carried out. RESULTS: Fifty-six patients with RSL at a median age of 66 years were included. Of these, 18 patients (32%) had been referred for EVT from external departments or institutions. RSL was associated with a relevant clinical deterioration in all patients, and 55 patients (98%) had been classified as ASA 3 and 4, preoperatively. In 9 patients (16%), additional surgical revision was necessary with initiation of EVT. In 47 patients (84%), EVT was successful and local control of the inflammatory focus was achieved. The median duration of therapy was 20 days. Two patients (4%) suffered from minor EVT-associated bleeding that was endoscopically controlled. Preoperative radiation of the pelvis was significantly associated with EVT failure (P = 0.035), whereas patient age represented a predictive factor for therapy length (P = 0.039). In 12 patients (21%), restoration of intestinal continuity was achieved in the further course. CONCLUSIONS: We present the first specific series on EVT for RSL. EVT for RSL was shown to be an effective and safe minimal-invasive treatment option, avoiding surgical revision in the majority of patients.

Experimental postoperative ileus: is Th2 immune response involved?

Rationale: Postoperative ileus (POI) is a frequent complication arising after gastrointestinal surgery but pathogenesis of POI is still not fully understood. While Th1 immune cells are implicated in POI, the involvement of Th2 cells has not yet been clarified. Given the impact of reactive oxygen species (ROS) in the regulation of Th1 and Th2 balance, we hypothesized that not only Th1 but also Th2 immune response can be involved in the development of experimental POI. Methods: The intestinal transit test was performed using carbon gum arabic. Electron microscopy was employed to assess tissue morphology and the presence of immune cells. Cytokines, IgE and ROS were measured. Immune cells from Peyer's patches were analyzed by Flow Cytometry and toluidine blue staining was used for detection of mast cells. Transcriptional factors were analyzed by Western blot. Results: POI is associated with an increase in both Th2 cytokines and Th2 cells. We have further demonstrated that POI induces a Th2-dependent activation of memory and non-memory B cells. This was accompanied by an increase in a number of mast cells in the colon of POI mice as well by an increased IgE and histamine plasma levels. We found that POI-induced accumulation of ROS was associated with an increased expression of the transcriptional factors HMBGI, NF-κB, and p38. This increased expression seemed to be associated with a Th2 response. Conclusion: Th2 immune response can be involved in the activation of mast cells in POI, which was associated with ROS mediated activation of NF-κB and p38 MAPK signaling pathway.

Improved survival after resection of colorectal liver metastases in patients with unresectable lung metastases.

BACKGROUND: Modern systemic therapies considerably improve tumour control and thus open the possibility of new surgical approaches in metastatic colorectal cancer. In this retrospective clinical cohort with a comparison group, we investigated whether liver resection in a combined liver-lung-metastasised stage is justified if pulmonary disease is not resected. METHODS: From 283 patients treated in our institution between 2000 and 2014 for combined colorectal liver- and lung metastases, 35 patients had their pulmonary metastases left in situ while they were eligible for both treatment options: resection versus non-resection of liver metastases. Effectively, 15 of these patients received whereas 20 did not receive a liver resection. In these patients, we compared overall survival and determined risk factors that are associated with poor survival, applying a Cox-Proportional Hazards model. RESULTS: Patients whose liver metastases were resected showed significantly longer median survival compared to patients who did not undergo hepatic surgery (median 2.6 vs 1.5 years, P = 0.0182). The Cox-Proportional Hazards model revealed hepatic metastasectomy to be the strongest determinant of patient survival (HR 5.27; CI: (1.89, 14.65)). CONCLUSION: Our results suggest that surgical removal of liver metastases may be beneficial in selected patients even if concomitant lung metastases cannot be resected.

A Novel Chimeric Oncolytic Virus Vector for Improved Safety and Efficacy as a Platform for the Treatment of Hepatocellular Carcinoma.

Oncolytic viruses represent an exciting new aspect of the evolving field of cancer immunotherapy. We have engineered a novel hybrid vector comprising vesicular stomatitis virus (VSV) and Newcastle disease virus (NDV), named recombinant VSV-NDV (rVSV-NDV), wherein the VSV backbone is conserved but its glycoprotein has been replaced by the hemagglutinin-neuraminidase (HN) and the modified, hyperfusogenic fusion (F) envelope proteins of recombinant NDV. In comparison to wild-type VSV, which kills cells through a classical cytopathic effect, the recombinant virus is able to induce tumor-specific syncytium formation, allowing efficient cell-to-cell spread of the virus and a rapid onset of immunogenic cell death. Furthermore, the glycoprotein exchange substantially abrogates the off-target effects in brain and liver tissue associated with wild-type VSV, resulting in a markedly enhanced safety profile, even in immune-deficient NOD.CB17-prkdcscid/NCrCrl (NOD-SCID) mice, which are highly susceptible to wild-type VSV. Although NDV causes severe pathogenicity in its natural avian hosts, the incorporation of the envelope proteins in the chimeric rVSV-NDV vector is avirulent in embryonated chicken eggs. Finally, systemic administration of rVSV-NDV in orthotopic hepatocellular carcinoma (HCC)-bearing immune-competent mice resulted in significant survival prolongation. This strategy, therefore, combines the beneficial properties of the rapidly replicating VSV platform with the highly efficient spread and immunogenic cell death of a fusogenic virus without risking the safety and environmental threats associated with either parental vector. Taking the data together, rVSV-NDV represents an attractive vector platform for clinical translation as a safe and effective oncolytic virus.IMPORTANCE The therapeutic efficacy of oncolytic viral therapy often comes as a tradeoff with safety, such that potent vectors are often associated with toxicity, while safer viruses tend to have attenuated therapeutic effects. Despite promising preclinical data, the development of VSV as a clinical agent has been substantially hampered by the fact that severe neurotoxicity and hepatotoxicity have been observed in rodents and nonhuman primates in response to treatment with wild-type VSV. Although NDV has been shown to have an attractive safety profile in humans and to have promising oncolytic effects, its further development has been severely restricted due to the environmental risks that it poses. The hybrid rVSV-NDV vector, therefore, represents an extremely promising vector platform in that it has been rationally designed to be safe, with respect to both the recipient and the environment, while being simultaneously effective, both through its direct oncolytic actions and through induction of immunogenic cell death.

Identification of novel agonists by high-throughput screening and molecular modelling of human constitutive androstane receptor isoform 3.

Prediction of drug interactions, based on the induction of drug disposition, calls for the identification of chemicals, which activate xenosensing nuclear receptors. Constitutive androstane receptor (CAR) is one of the major human xenosensors; however, the constitutive activity of its reference variant CAR1 in immortalized cell lines complicates the identification of agonists. The exclusively ligand-dependent isoform CAR3 represents an obvious alternative for screening of CAR agonists. As CAR3 is even more abundant in human liver than CAR1, identification of its agonists is also of pharmacological value in its own right. We here established a cellular high-throughput screening assay for CAR3 to identify ligands of this isoform and to analyse its suitability for identifying CAR ligands in general. Proof-of-concept screening of 2054 drug-like compounds at 10 µM resulted in the identification of novel CAR3 agonists. The CAR3 assay proved to detect the previously described CAR1 ligands in the screened libraries. However, we failed to detect CAR3-selective compounds, as the four novel agonists, which were selected for further investigations, all proved to activate CAR1 in different cellular and in vitro assays. In primary human hepatocytes, the compounds preferentially induced the expression of the prototypical CAR target gene CYP2B6. Failure to identify CAR3-selective compounds was investigated by molecular modelling, which showed that the isoform-specific insertion of five amino acids did not impact on the ligand binding pocket but only on heterodimerization with retinoid X receptor. In conclusion, we demonstrate here the usability of CAR3 for screening compound libraries for the presence of CAR agonists.

Prediction of human drug-induced liver injury (DILI) in relation to oral doses and blood concentrations.

Drug-induced liver injury (DILI) cannot be accurately predicted by animal models. In addition, currently available in vitro methods do not allow for the estimation of hepatotoxic doses or the determination of an acceptable daily intake (ADI). To overcome this limitation, an in vitro/in silico method was established that predicts the risk of human DILI in relation to oral doses and blood concentrations. This method can be used to estimate DILI risk if the maximal blood concentration (Cmax) of the test compound is known. Moreover, an ADI can be estimated even for compounds without information on blood concentrations. To systematically optimize the in vitro system, two novel test performance metrics were introduced, the toxicity separation index (TSI) which quantifies how well a test differentiates between hepatotoxic and non-hepatotoxic compounds, and the toxicity estimation index (TEI) which measures how well hepatotoxic blood concentrations in vivo can be estimated. In vitro test performance was optimized for a training set of 28 compounds, based on TSI and TEI, demonstrating that (1) concentrations where cytotoxicity first becomes evident in vitro (EC10) yielded better metrics than higher toxicity thresholds (EC50); (2) compound incubation for 48 h was better than 24 h, with no further improvement of TSI after 7 days incubation; (3) metrics were moderately improved by adding gene expression to the test battery; (4) evaluation of pharmacokinetic parameters demonstrated that total blood compound concentrations and the 95%-population-based percentile of Cmax were best suited to estimate human toxicity. With a support vector machine-based classifier, using EC10 and Cmax as variables, the cross-validated sensitivity, specificity and accuracy for hepatotoxicity prediction were 100, 88 and 93%, respectively. Concentrations in the culture medium allowed extrapolation to blood concentrations in vivo that are associated with a specific probability of hepatotoxicity and the corresponding oral doses were obtained by reverse modeling. Application of this in vitro/in silico method to the rat hepatotoxicant pulegone resulted in an ADI that was similar to values previously established based on animal experiments. In conclusion, the proposed method links oral doses and blood concentrations of test compounds to the probability of hepatotoxicity.

Nonparametric change point estimation for survival distributions with a partially constant hazard rate.

We present a new method for estimating a change point in the hazard function of a survival distribution assuming a constant hazard rate after the change point and a decreasing hazard rate before the change point. Our method is based on fitting a stump regression to p values for testing hazard rates in small time intervals. We present three real data examples describing survival patterns of severely ill patients, whose excess mortality rates are known to persist far beyond hospital discharge. For designing survival studies in these patients and for the definition of hospital performance metrics (e.g. mortality), it is essential to define adequate and objective end points. The reliable estimation of a change point will help researchers to identify such end points. By precisely knowing this change point, clinicians can distinguish between the acute phase with high hazard (time elapsed after admission and before the change point was reached), and the chronic phase (time elapsed after the change point) in which hazard is fairly constant. We show in an extensive simulation study that maximum likelihood estimation is not robust in this setting, and we evaluate our new estimation strategy including bootstrap confidence intervals and finite sample bias correction.

Bone marrow-derived mesenchymal stromal cells promote colorectal cancer cell death under low-dose irradiation.

BACKGROUND: Radiotherapy remains one of the cornerstones to improve the outcome of colorectal cancer (CRC) patients. Radiotherapy of the CRC not only help to destroy cancer cells but also remodel the tumour microenvironment by enhancing tumour-specific tropism of bone marrow-derived mesenchymal stromal cell (BM-MSC) from the peripheral circulation. However, the role of local MSCs and recruited BM-MSC under radiation were not well defined. Indeed, the functions of BM-MSC without irradiation intervention remained controversial in tumour progression: BM-MSC was previously shown to modulate the immune function of major immune cells, resulting in an impaired immunological sensitivity and to induce an increased risk of tumour recurrence. In contrast, it could also secrete various cytokines and possess anticancer effect. METHODS: Three co-cultivation modules, 3D culture modules, and cancer organoids were established. The induction of cytokines secretion in hBM-MSCs after irradiation was analysed by ELISA array and flow cytometry. AutoMac separator was used to separate hBM-MSC and CRC automatically. Cells from the co-cultured group and the control group were then irradiated by UV-C lamp and X-ray. Proliferation assay and viability assay were performed. RESULTS: In this study, we show that BM-MSCs can induce the EMT progression of CRC cells in vitro. When irradiated with low doses of ultraviolet radiation and X-rays, BM-MSCs show an anti-tumour effect by secreting certain cytokine (TNF-α, IFN-γ) that lead to the inhibition of proliferation and induction of apoptosis of CRC cells. This was further verified in a 3D culture model of a CRC cell in vitro. Furthermore, irradiation on the co-culture system induced the cleavage of caspase3, and attenuated the phosphorylation of phosphatidylinositol 3-kinase (PI3K)/AKT and extracellular signal-regulated kinase in cancer cells. The signal pathways above might contribute to the cancer cell death. CONCLUSIONS: Taken together, we show that BM-MSC can potentially promote the effect of radiotherapy in CRC.

Successful treatment of enteroatmospheric fistulas in combination with negative pressure wound therapy: Experience on 3 cases and literature review.

Enteroatmospheric fistulas (EAF) are rare but challenging and morbid complications of abdominal surgery and require time- as well as resource-consuming management. Furthermore, they severely affect patients' quality of life. Several treatment modalities for EAF management are described in the literature. We describe 3 consecutive cases of EAF treatment by employing negative pressure wound therapy (NPWT) along with either a special silicone fistula adapter or a Silo-Vac-like system in another case to isolate the fistula from the remaining abdominal wound. Spontaneous fistula closure was achieved in 2 of the 3 cases, and surgical resection of the small bowel segment harbouring EAF opening was possible in a third case after wound conditioning. The rate of fistula closure was 100% (n = 3/3). Compartmentalisation of the contaminated area using NPWT accelerated healing of the open abdominal wound remarkably. In summary, we present a useful tool for the challenging management of EAF and review the literature on different treatment options of EAF available today.

Long-term Quality of Life of Patients With Permanent End Ileostomy: Results of a Nationwide Cross-Sectional Survey.

BACKGROUND: Patients with permanent end ileostomy are at high risk for detrimental stomal effects on their quality of life. However, little is known about the long-term quality of life of these patients. OBJECTIVE: The purpose of this study was to assess long-term quality of life in patients with permanent end ileostomy. DATA SOURCES: Registration at the German self-help organization ILCO was used for this study. STUDY SELECTION: Selection included a cross-sectional survey of 1434 patients with permanent end ileostomy. MAIN OUTCOME MEASURES: Quality of life was assessed using the Medical Outcomes Study Short Form 36, including physical and mental component summary scores, the Gastrointestinal Quality of Life Index, and the Cleveland Global Quality of Life Index. Multivariate risk factor analysis was performed. RESULTS: A total of 783 responders were included. Indications for ileostomy included ulcerative colitis (44%), Crohn's disease (38%), and colorectal cancer (7%). Adverse effects on daily life because of stoma were reported by 72% of participants. Quality of life was significantly impaired compared with the general population on all of the summary scores and several subscales (physical component summary: 44.6 ± 10.4 (mean ± SD) vs 50.2 ± 10.2, p < 0.001; mental component summary: 47.5 ± 10.7 vs 51.5 ± 10.2, p < 0.001; Gastrointestinal Quality of Life Index: 94.4 ± 16.4 vs 126.0, p < 0.001). Stoma care problems affecting quality of life were reported by 63% of respondents. These included parastomal hernia (p < 0.001), stenosis (p = 0.003), and prolapse (p = 0.008). Vitamin B12, iron, and zinc deficiencies were also associated with diminished quality of life; in particular, vitamin B12 deficiency was associated with reduced mental and emotional quality of life. LIMITATIONS: Not all patients undergoing ileostomy in Germany are registered at ILCO, and there were many nonresponders. In addition, the inherent limitations of cross-sectional studies should be considered, including the response-shift phenomenon. CONCLUSIONS: Quality of life was markedly impaired in patients with permanent end ileostomy as compared with the general population. The main reasons were stoma-associated morbidity and nutritional deficiency syndromes. These findings highlight the importance of prevention, screening, and adequate treatment.

Synchronous colorectal liver metastases: focus on the elderly : An Effectiveness Study from Routine Care.

PURPOSE: The goal of this study was to analyze the use and the effectiveness of both surgery and different chemotherapies in patients with synchronous colorectal liver metastases (CLMs) ≥70 years compared to younger patients. METHODS: Survival was analyzed in 456 patients (24.3% ≥70 years) treated for CLM in a single center using Kaplan-Meier estimation of overall survival (OS), calculation of relative survival as estimate for disease-specific survival, and a Cox regression model. RESULTS: Complete surgical resections were achieved more often in patients aged <70 years (39.2 vs. 28.1%, P = 0.056), and young patients more frequently received irinotecan or platin-based chemotherapies (70.3 vs. 41.6%, P < 0.001). Three-year OS and relative survival of patients ≥70 years were significantly lower compared to younger patients (OS 34.3 vs. 43.5%, P = 0.0114). In a Cox regression model, complete surgical removal of liver metastases was the most effective treatment (HR 0.313, P < 0.001) followed by chemotherapy (irinotecan/platin-based: HR 0.371, 5-FU only: HR 0.673, P < 0.001). Having >5 liver metastases, the presence of extrahepatic metastases, high grading, and a nodal positive primary but not age ≥70 years were associated with an increased risk of death. CONCLUSIONS: Our data support radical resection and highly effective chemotherapy in selected elderly patients with CLM.

Time-dependent impact of age and comorbidities on long-term overall survival after liver resection.

BACKGROUND & AIMS: Advanced age and comorbidities are known to be associated with increased perioperative risks after liver resection. However, the precise impact of these variables on long-term overall survival (OS) remains unclear. Thus, the aim of this study was to evaluate the confounder-adjusted, time-dependent effect of age and comorbidities on OS following hepatectomy for primary and secondary malignancies. METHODS: From a prospective database of 1.143 liver resections, 763 patients treated for primary and secondary malignancies were included. For time-varying OS calculations, a Cox-Aalen model was fitted. The confounder-adjusted hazard was compared with mortality tables of the German population. RESULTS: Overall, age (P = 0.003) and comorbidities (P = 0.001) were associated with shortened OS. However, time-dependent analysis indicated that age and comorbidities had no impact on OS within 39 and 55 months after resection respectively. From this time on, a significant decline in OS was shown. Subgroup analysis indicated an earlier increase of the effect of age in patients with hepatocellular carcinoma (17 months) than in those with colorectal metastases (70 months). The confounder-adjusted hazard of 70-year-old patients was increased post-operatively but dropped 66 months after surgery, and the risk of death was comparable to the general population 78 months after resection. At this time, one-third of patients aged 70 years and older were still alive. CONCLUSIONS: With regard to long-term outcome, liver resection for both primary and secondary malignancies should not be categorically denied due to age and comorbidities. This information should be considered for the patient selection process and informed consent.

Effectiveness of triclosan-coated PDS Plus versus uncoated PDS II sutures for prevention of surgical site infection after abdominal wall closure: the randomised controlled PROUD trial.

BACKGROUND: Postoperative surgical site infections are one of the most frequent complications after open abdominal surgery, and triclosan-coated sutures were developed to reduce their occurrence. The aim of the PROUD trial was to obtain reliable data for the effectiveness of triclosan-coated PDS Plus sutures for abdominal wall closure, compared with non-coated PDS II sutures, in the prevention of surgical site infections. METHODS: This multicentre, randomised controlled group-sequential superiority trial was done in 24 German hospitals. Adult patients (aged ≥18 years) who underwent elective midline abdominal laparotomy for any reason were eligible for inclusion. Exclusion criteria were impaired mental state, language problems, and participation in another intervention trial that interfered with the intervention or outcome of this trial. A central web-based randomisation tool was used to randomly assign eligible participants by permuted block randomisation with a 1:1 allocation ratio and block size 4 before mass closure to either triclosan-coated sutures (PDS Plus) or uncoated sutures (PDS II) for abdominal fascia closure. The primary endpoint was the occurrence of superficial or deep surgical site infection according to the Centers for Disease Control and Prevention criteria within 30 days after the operation. Patients, surgeons, and the outcome assessors were masked to group assignment. Interim and final analyses were by modified intention to treat. This trial is registered with the German Clinical Trials Register, number DRKS00000390. FINDINGS: Between April 7, 2010, and Oct 19, 2012, 1224 patients were randomly assigned to intervention groups (607 to PDS Plus, and 617 to PDS II), of whom 1185 (587 PDS Plus and 598 PDS II) were analysed by intention to treat. The study groups were well balanced in terms of patient and procedure characteristics. The occurrence of surgical site infections did not differ between the PDS Plus group (87 [14·8%] of 587) and the PDS II group (96 [16·1%] of 598; OR 0·91, 95% CI 0·66-1·25; p=0·64). Serious adverse events also did not differ between the groups-146 of 583 (25·0%) patients treated with PDS Plus had at least one serious adverse event, compared with 138 of 602 (22·9%) patients treated with PDS II; p=0·39). INTERPRETATION: Triclosan-coated PDS Plus did not reduce the occurrence of surgical site infection after elective midline laparotomy. Innovative, multifactorial strategies need to be developed and assessed in future trials to reduce surgical site infections. FUNDING: Johnson & Johnson Medical Limited.