Specific MicroRNA Pattern in Colon Tissue of Young Children with Eosinophilic Colitis

Eosinophilic colitis (EC) is a common cause of haematochezia in infants and young children. The exact pathomechanism is not understood, and the diagnosis is challenging. The role of microRNAs as key class of regulators of mRNA expression and translation in patients with EC has not been explored. Therefore, the aim of the present study was to explore the miRNA profile in EC with respect to eosinophilic inflammation. Patients enrolled in the study (n = 10) had persistent rectal bleeding, and did not respond to elimination dietary treatment. High-throughput microRNA sequencing was carried out on colonic biopsy specimens of children with EC (EC: n = 4) and controls (C: n = 4) as a preliminary screening of the miRNA profile. Based on the next-generation sequencing (NGS) results and literature data, a potentially relevant panel of miRNAs were selected for further measurements by real-time reverse transcription (RT)-PCR (EC: n = 14, C: n = 10). Validation by RT-PCR resulted in significantly altered expression of miR-21, -31, -99b, -125a, -146a, -184, -221, -223, and -559 compared to controls (p </= 0.05). Elevation in miR-21, -99b, -146a, -221, and -223 showed statistically significant correlation to the extent of tissue eosinophilia. Based on our results, we conclude that the dysregulated miRNAs have a potential role in the regulation of apoptosis by targeting Protein kinase B/Mechanistic target of rapamycin (AKT/mTOR)-related pathways in inflammation by modulating Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kappaB)-related signalling and eosinophil cell recruitment and activation, mainly by regulating the expression of the chemoattractant eotaxin and the adhesion molecule CD44. Our results could serve as a basis for further extended research exploring the pathomechanism of EC

Autonóm robotok korszerű irányításelméletének, navigációjának és az intelligencia növelésének kutatása = Research in the advanced control theory and navigation of autonomous robots and the increase of the intelligence

Módszereket dolgoztunk ki redundáns mobilis robotok mozgásának koordinálására es a mozgás optimális megosztására a platform és a robot között. Rétegezett irányításon és játékelméleten alapuló mozgástervezési és irányítási algoritmusokat dolgoztunk ki multiágensű rendszerek számára. Tárgymanipulációs algoritmusokat fejlesztettünk ki kooperáló robotok és többujjas robotkezek irányításához mesterséges intelligencia eszközök bevonásával. Módszereket adtunk járművek és intelligens beavatkozó szerveik modellezésére, pályatervezésére és korszerű irányításukra. Adaptív irányítási algoritmusokat fejlesztettünk ki mechatronikai rendszerek és robotok súrlódási jelenségeinek modellezésére és kompenzálására. Földi járművek automatikus akadályelerülésére pályatervezési módszert és prediktív irányítási algoritmust dolgoztunk ki. Sztereó képfeldolgozási módszereket fejlesztettünk ki a 3D jelenet rekonstruálására, az objektumok felismerésére és a tárgyak relatív helyzetének meghatározására. Robotok kézmozdulatokkal történő irányításához és a teleoperációhoz kidolgoztuk az emberi kéz részletes kinematikai modelljét. Mobilis és mikrorobotok viselkedésorientált irányításához platform független szimulátort fejlesztettünk ki, amely csökkenti a tervezési fázis költségét és a meghibásodás kockázatát. Ipari robot hibrid pozíció/erő irányításához új architektúrát, kommunikációs megoldásokat és szoftver platformot fejlesztettünk ki, amely megkönnyíti a valósidejű irányító szoftverek fejlesztését. | Methods were developed to coordinate the motion of redundant mobile robots allowing optimal task distribution between platform and robot arm. Motion design and control algorithms using stratified control and game theory were developed for multiagent systems. Object manipulation algorithms were elaborated to the control of cooperating robots and multifingered dexterous hands integrating artificial intelligence tools. Methods were given for modeling, path design, and advanced control of vehicles and their intelligent actuators. Adaptive control algorithms were developed for friction modeling and compensation in mechatronic and robotic systems. A path design method and a predictive control algorithm were elaborated for Collision Avoidance Systems of ground vehicles. Stereo image processing methods were developed for 3D reconstruction, object recognition, and for the determination of the relative pose among objects. A detailed kinematic model of the human hand was elaborated for the control and teleoperation of robots by hand gestures. A platform independent simulator was developed for the behavior based control of mobile and micro robots which decreases the cost of the design phase and reduces the risk of failures. A new architecture, communication solutions, and a software platform were developed for the hybrid position/force control of industrial robots facilitating the design of the real time control software tools

Thiopurines impair the apical plasma membrane expression of CFTR in pancreatic ductal cells via RAC1 inhibition

Thiopurine-induced acute pancreatitis (TIP) is one of the most common adverse events among inflammatory bowel disease patients treated with azathioprine (AZA), representing a significant clinical burden. Previous studies focused on immune-mediated processes, however, the exact pathomechanism of TIP is essentially unclear.To model TIP in vivo, we triggered cerulein-induced experimental pancreatitis in mice receiving a daily oral dose of 1.5 mg/kg AZA. Also, freshly isolated mouse pancreatic cells were exposed to AZA ex vivo, and acinar cell viability, ductal and acinar Ca2+ signaling, ductal Cl- and HCO3- secretion, as well as cystic fibrosis transmembrane conductance regulator (CFTR) expression were assessed using microscopy techniques. Ras-related C3 botulinum toxin substrate (RAC1) activity was measured with a G-LISA assay. Super-resolution microscopy was used to determine protein colocalization.We demonstrated that AZA treatment increases tissue damage in the early phase of cerulein-induced pancreatitis in vivo. Also, both per os and ex vivo AZA exposure impaired pancreatic fluid and ductal HCO3- and Cl- secretion, but did not affect acinar cells. Furthermore, ex vivo AZA exposure also inhibited RAC1 activity in ductal cells leading to decreased co-localization of CFTR and the anchor protein ezrin, resulting in impaired plasma membrane localization of CFTR.AZA impaired the ductal HCO3- and Cl- secretion through the inhibition of RAC1 activity leading to diminished ezrin-CFTR interaction and disturbed apical plasma membrane expression of CFTR. We report a novel direct toxic effect of AZA on pancreatic ductal cells and suggest that the restoration of ductal function might help to prevent TIP in the future

Eosinophil Counts in the Small Intestine and Colon of Children Without Apparent Gastrointestinal Disease: a Meta-analysis

OBJECTIVES: The aim of the current study was to review the available data regarding eosinophil density in healthy tissue specimen originating from lower gastrointestinal segments to support suggested diagnostic cut-offs widely used in clinical practice. METHODS: A systematic search was performed in three different databases. Calculations were made with Comprehensive MetaAnalysis software using random effects model. Cell number measurements were pooled using the random effects model and displayed on forest plots. Summary point estimations, 95% Confidence Intervals (CIs), and 95% Prediction Intervals (PIs) were calculated. RESULTS: The cumulative mean cell numbers were 8.26 (95% CI: 3.49, 13.03) with PI of 0-25.32 for the duodenum, 11.51 (95% CI: 7.21, 15.82) with PI of 0-60.59 for the terminal ileum, and 11.10/HPF (95% CI: 9.11, 13.09) with PI of 0.96-21.23 in the large intestine and the rectum (HPF area = 0.2 mm). Previous studies included control patients with irritable bowel syndrome (IBS) and functional GI disorders. As mucosal eosinophils have a role in their pathomechanism, those patients should have been excluded. A critical point of interpreting reported data is that HPF is relative to the technical parameters of the microscopes, therefore it is important to report findings in cell/mm. CONCLUSIONS: The present meta-analysis does not support the higher (>20) or lower (<10) cut-off values for healthy tissue eosinophil number. In contrast to the esophagus, there is no normal cut-off eosinophil density in the small intestine and the colon. A prospective, multi-center study to establish normal mucosal eosinophil density is clearly needed

Impaired regulation of PMCA activity by defective CFTR expression promotes epithelial cell damage in alcoholic pancreatitis and hepatitis

Alcoholic pancreatitis and hepatitis are frequent, potentially lethal diseases with limited treatment options. Our previous study reported that the expression of CFTR Cl- channel is impaired by ethanol in pancreatic ductal cells leading to more severe alcohol-induced pancreatitis. In addition to determining epithelial ion secretion, CFTR has multiple interactions with other proteins, which may influence intracellular Ca2+ signaling. Thus, we aimed to investigate the impact of ethanol-mediated CFTR damage on intracellular Ca2+ homeostasis in pancreatic ductal epithelial cells and cholangiocytes. Human and mouse pancreas and liver samples and organoids were used to study ion secretion, intracellular signaling, protein expression and interaction. The effect of PMCA4 inhibition was analyzed in a mouse model of alcohol-induced pancreatitis. The decreased CFTR expression impaired PMCA function and resulted in sustained intracellular Ca2+ elevation in ethanol-treated and mouse and human pancreatic organoids. Liver samples derived from alcoholic hepatitis patients and ethanol-treated mouse liver organoids showed decreased CFTR expression and function, and impaired PMCA4 activity. PMCA4 co-localizes and physically interacts with CFTR on the apical membrane of polarized epithelial cells, where CFTR-dependent calmodulin recruitment determines PMCA4 activity. The sustained intracellular Ca2+ elevation in the absence of CFTR inhibited mitochondrial function and was accompanied with increased apoptosis in pancreatic epithelial cells and PMCA4 inhibition increased the severity of alcohol-induced AP in mice. Our results suggest that improving Ca2+ extrusion in epithelial cells may be a potential novel therapeutic approach to protect the exocrine pancreatic function in alcoholic pancreatitis and prevent the development of cholestasis in alcoholic hepatitis

Thiopurines Impair the Apical Plasma Membrane Expression of CFTR in Pancreatic Ductal Cells via RAC1 Inhibition

Background and aims Thiopurine-induced acute pancreatitis (TIP) is one of the most common adverse events among infammatory bowel disease patients treated with azathioprine (AZA), representing a signifcant clinical burden. Previous studies focused on immune-mediated processes, however, the exact pathomechanism of TIP is essentially unclear. Methods To model TIP in vivo, we triggered cerulein-induced experimental pancreatitis in mice receiving a daily oral dose of 1.5 mg/kg AZA. Also, freshly isolated mouse pancreatic cells were exposed to AZA ex vivo, and acinar cell viability, ductal and acinar Ca2+ signaling, ductal Cl–and HCO3–secretion, as well as cystic fbrosis transmembrane conductance regulator (CFTR) expression were assessed using microscopy techniques. Ras-related C3 botulinum toxin substrate (RAC1) activity was measured with a G-LISA assay. Super-resolution microscopy was used to determine protein colocalization. Results We demonstrated that AZA treatment increases tissue damage in the early phase of cerulein-induced pancreatitis in vivo. Also, both per os and ex vivo AZA exposure impaired pancreatic fuid and ductal HCO3– and Cl–secretion, but did not afect acinar cells. Furthermore, ex vivo AZA exposure also inhibited RAC1 activity in ductal cells leading to decreased co-localization of CFTR and the anchor protein ezrin, resulting in impaired plasma membrane localization of CFTR. Conclusions AZA impaired the ductal HCO3– and Cl–secretion through the inhibition of RAC1 activity leading to diminished ezrin-CFTR interaction and disturbed apical plasma membrane expression of CFTR. We report a novel direct toxic efect of AZA on pancreatic ductal cells and suggest that the restoration of ductal function might help to prevent TIP in the future