Influence of temperature fluctuations on plasma turbulence investigations with Langmuir probes

The reliability of Langmuir probe measurements for plasma-turbulence investigations is studied on GEMR gyro-fluid simulations and compared with results from conditionally sampled I-V characteristics as well as self-emitting probe measurements in the near scrape-off layer of the tokamak ASDEX Upgrade. In this region, simulation and experiment consistently show coherent in-phase fluctuations in density, plasma potential and also in electron temperature. Ion-saturation current measurements turn out to reproduce density fluctuations quite well. Fluctuations in the floating potential, however, are strongly influenced by temperature fluctuations and, hence, are strongly distorted compared to the actual plasma potential. These results suggest that interpreting floating as plasma-potential fluctuations while disregarding temperature effects is not justified near the separatrix of hot fusion plasmas. Here, floating potential measurements lead to corrupted results on the ExB dynamics of turbulent structures in the context of, e.g., turbulent particle and momentum transport or instability identification on the basis of density-potential phase relations

Paneth and Intestinal Stem Cells Preserve their Functional Integrity during Worsening of Acute Cellular Rejection in Small Bowel Transplantation

Graft survival after small bowel transplantation remains impaired due to acute cellular rejection (ACR), the leading cause of graft loss. Although it was shown that the number of enteroendocrine progenitor cells in intestinal crypts was reduced during mild ACR, no results of Paneth and intestinal stem cells localized at the crypt bottom have been shown so far. Therefore, we wanted to elucidate integrity and functionality of the Paneth and stem cells during different degrees of ACR, and to assess whether these cells are the primary targets of the rejection process. We compared biopsies from ITx patients with no, mild or moderate ACR by immunohistochemistry and quantitative PCR. Our results show that numbers of Paneth and stem cells remain constant in all study groups, whereas the transit-amplifying zone is the most impaired zone during ACR. We detected an unchanged level of antimicrobial peptides in Paneth cells and similar numbers of Ki-67+ IL-22R+ stem cells revealing cell functionality in moderate ACR samples. We conclude that Paneth and stem cells are not primary target cells during ACR. IL-22R+ Ki-67+ stem cells might be an interesting target cell population for protection and regeneration of the epithelial monolayer during/after a severe ACR in ITx patients.Fil: Pucci Molineris, Melisa Eliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Medicina Traslacional, Trasplante y Bioingeniería. Fundación Favaloro. Instituto de Medicina Traslacional, Trasplante y Bioingeniería; ArgentinaFil: Gonzalez Polo, Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Medicina Traslacional, Trasplante y Bioingeniería. Fundación Favaloro. Instituto de Medicina Traslacional, Trasplante y Bioingeniería; ArgentinaFil: Pérez, Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Estudios Inmunológicos y Fisiopatológicos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Estudios Inmunológicos y Fisiopatológicos; ArgentinaFil: Ramisch, D.. Fundación Favaloro; ArgentinaFil: Rumbo, Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Estudios Inmunológicos y Fisiopatológicos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Estudios Inmunológicos y Fisiopatológicos; ArgentinaFil: Gondolesi, Gabriel Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Medicina Traslacional, Trasplante y Bioingeniería. Fundación Favaloro. Instituto de Medicina Traslacional, Trasplante y Bioingeniería; ArgentinaFil: Meier, D.. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Medicina Traslacional, Trasplante y Bioingeniería. Fundación Favaloro. Instituto de Medicina Traslacional, Trasplante y Bioingeniería; Argentin

Paneth and intestinal stem cells preserve their functional integrity during worsening of acute cellular rejection in small bowel transplantation

Graft survival after small bowel transplantation remains impaired due to acute cellular rejection (ACR), the leading cause of graft loss. Although it was shown that the number of enteroendocrine progenitor cells in intestinal crypts was reduced during mild ACR, no results of Paneth and intestinal stem cells localized at the crypt bottom have been shown so far. Therefore, we wanted to elucidate integrity and functionality of the Paneth and stem cells during different degrees of ACR, and to assess whether these cells are the primary targets of the rejection process. We compared biopsies from ITx patients with no, mild or moderate ACR by immunohistochemistry and quantitative PCR. Our results show that numbers of Paneth and stem cells remain constant in all study groups, whereas the transit-amplifying zone is the most impaired zone during ACR. We detected an unchanged level of antimicrobial peptides in Paneth cells and similar numbers of Ki-67+ IL-22R+ stem cells revealing cell functionality in moderate ACR samples. We conclude that Paneth and stem cells are not primary target cells during ACR. IL-22R+ Ki-67+ stem cells might be an interesting target cell population for protection and regeneration of the epithelial monolayer during/after a severe ACR in ITx patients.Instituto de Estudios Inmunológicos y Fisiopatológico

Neo-Suprahepatic cava: A case report of a modified technique for domino liver transplantation

Domino liver transplantation, introduced in 1997, originally consisted of a graft from a patient with familial amyloidotic polyneuropathy used as a donor for a compatible recipient, thus increasing the pool of hepatic grafts for liver transplantation. The aim of this report was to present a modification on the technique for outflow reconstruction in domino liver transplantation first proposed by Liu et al and Cescon et al. In this description we proposed a new technique that differs from the one mentioned above by performing a neo-suprahepatic cava, constructed using only an iliac vein graft, facilitating the anastomosis as if it was a regular cadaveric liver transplant.Fil: Padín, J. M.. Fundación Favaloro; ArgentinaFil: Pfaffen, G.. Fundación Favaloro; ArgentinaFil: Pérez Fernández, I.. Fundación Favaloro; ArgentinaFil: Sandi, M.. Fundación Favaloro; ArgentinaFil: Ramisch, D.. Fundación Favaloro; ArgentinaFil: Barros Schelotto, P.. Fundación Favaloro; ArgentinaFil: Gondolesi, Gabriel Eduardo. Fundación Favaloro; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Perioperative fluid management and postoperative complications after laparoscopic distal pancreatectomy

A pesar de que la mortalidad de la cirugía pancreática hadisminuido en las últimas décadas, la morbilidad permanecealta. Una de las causas más importantes de esta es la fístulapancreática postoperatoria. Estudios recientes han demostradola influencia de la fluidoterapia perioperatoria en losresultados postoperatorios de cirugías abdominales mayores.Esto se evidenció fundamentalmente en cirugía de colon, demostrandoque la sobrecarga hídrica aumenta las complicacionespostoperatorias. Objetivo. Evaluar la influenciade la fluidoterapia en la morbilidad post pancreatectomíadistal videolaparoscópica. Material y métodos. Estudioretrospectivo, de una base de datos prospectiva de pacientessometidos a pancreatectomía distal videolaparoscópica denoviembre de 2011 a septiembre de 2018. Se evaluaron30 pacientes que se dividieron en dos grupos según la fluidoterapiaadministrada (restrictiva o liberal). Los datos serecolectaron de los protocolos de anestesia y de los controles en sala de internación (hasta el 3° día postoperatorio).Se analizaron variables demográficas, tiempo de estadíahospitalaria, tipo de fluidoterapia y complicaciones. Parael análisis estadístico se utilizó SPSS® v.21. (p < 0,05 fueconsiderado significativo). Resultados. De los 30 pacientes,el 17% eran hombres, edad media de 54 ± 18 años; 17pacientes (57%) pertenecían a grupo liberal y 13 (43%) algrupo restrictivo. Veintitrés pacientes presentaron complicaciones,16 (53%) fueron del grupo liberal y 7 (23%) delgrupo restrictivo, (p = 0,01). Catorce pacientes del grupoliberal presentaron fístula pancreática postoperatoria vs. 6pacientes del grupo restrictivo (p = 0,04). En 7 pacientesdel grupo liberal (23%) y en 4 pacientes del grupo restrictivose presentó fistula pancreática clínicamente relevante(13%) (p = NS). La mortalidad de la serie fue de 3,3 %,no habiendo diferencias entre los grupos de estudio. Conclusión.Nuestros resultados sugieren que la restricción delíquidos en el perioperatorio reduce considerablemente latasa de complicaciones y el desarrollo de fístula pancreáticapostoperatoria, después de la pancreatectomía distal videolaparoscópica.Despite mortality in pancreatic surgery has decreased over the last decade, morbidity remains high. One of the most important causes is pancreatic fistula. Recent studies have demonstrated the importance of fluid therapy management during the perioperative period in major abdominal surgeries. This finding was observed first in colonic surgery, demonstrating that overload of fluids increases postoperative complications. Objective. To evaluate the impact of fluid management on postoperative complications after laparoscopic distal pancreatectomy. Material and methods. Descriptive, retrospective study of a prospective database of patients whom underwent laparoscopic distal pancreatectomy from November 2011 to September 2018. Thirty patients were evaluated and divided in two groups depending on the fluid management (restrictive, or liberal). The data were collected from the anesthesia protocols and nursery reports (until 3rd postoperative day). Demographics, length of stay, kind of fluid management and complications were analyzed. For statistical analysis SPSS®v.21 was used (p < 0.05 was considered significant). Results. Out of 30 patients, 17% were male, mean age was 55 ± 18 years (r 19-82); 17 patients (57%) were included in the liberal group and 13 (43%) in the restrictive group. Twenty-three patients developed complications; 16 (53%) belonged to liberal group whereas 7 (23%) to restrictive group. (p = 0.01). Fourteen patients of liberal group vs. 6 patients of restrictive group had postoperative pancreatic fistula (p = 0.04). There were 7 patients (23%) in liberal group. and 4 (13%) patients in restrictive group with clinically relevant pancreatic fistula (13%, p = NS). Ninety day-mortality was 3.3, with no differences between groups. Conclusion. After laparoscopic distal pancreatectomy, liberal fluid administration at the perioperative period is associated with an increase in the incidence of complication, specially favoring the development of pancreatic fistula.Fil: Lobos. Fernando D.. Fundación Favaloro; ArgentinaFil: Barros Schelotto, Pablo. Fundación Favaloro; ArgentinaFil: Ramisch, Diego. Fundación Favaloro; ArgentinaFil: Rubiolo, Agustín Santiago. Fundación Favaloro; ArgentinaFil: Montes, Leonardo. Fundación Favaloro; ArgentinaFil: Gondolesi, Gabriel Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Medicina Traslacional, Trasplante y Bioingeniería. Fundación Favaloro. Instituto de Medicina Traslacional, Trasplante y Bioingeniería; Argentin

Solid pseudopapillary tumor of the páncreas

Antecedentes: la neoplasia sólida pseudopapilar del páncreas es una entidad rara, que típicamente se presenta en mujeres jóvenes. Suele presentar síntomas abdominales inespecíficos. Es un tumor maligno de bajo grado de malignidad.Objetivos: el objetivo del siguiente informe de serie de casos es presentar 9 casos tratados en un centro y realizar una revisión bibliográfica del tema.Material y métodos: estudio retrospectivo descriptivo de los casos con diagnóstico anatomopatológico de neoplasia sólida pseudopapilar en el Servicio de Cirugía General, desde febrero de 2013 hasta septiembre de 2019. Se contemplaron como variables: edad, sexo, localización del tumor, tratamiento quirúrgico realizado, tiempo operatorio, complicaciones, estancia hospitalaria y seguimiento alejado.Resultados: fueron 9 casos, todos de sexo femenino con media de edad de 30 años (rango 20 a 70 años). La localización más frecuente fue en cola de páncreas en 4 casos (45%). Todas las pacientes fueron sometidas a cirugía, con abordaje laparoscópico en el 60% de los casos (n = 5); la resección pancreática distal con preservación esplénica fue la conducta más utilizada (n = 6). Se constataron tres complicaciones, de las cuales dos fueron colecciones abdominales como consecuencia de una fístula pancreática que se abordaron por vía percutánea, y la restante fue un retardo del vaciamiento gástrico por lo cual la paciente requirió internación prolongada.Conclusión: la neoplasia sólida pseudopapilar pancreática es una enfermedad poco frecuente, maligna pero con bajo riesgo de malignidad. Presenta buena sobrevida cuando se somete a cirugía de carácter curativo; la laparoscopia es la vía de abordaje de elección en centros con experiencia.Background: Solid pseudopapillary tumor of the pancreas is a rare condition that affects young women. The most common symptom is unspecific abdominal pain. It is a malignant tumor of low malignant potential. Objective: The aim of this study is to report a case series of patients treated in a single center and perform a bibliographic review. Material and methods: We conducted a retrospective study of the cases with pathological diagnosis of solid pseudopapillary tumor of the pancreas treated in the Department of General Surgery between February 2013 and September 2019. The following variables were analyzed; age, sex, tumor location, surgical treatment, operative time, complications, length of hospital stay and long-term follow-up. Results: Nine patients were included; all of them were women with mean age of 30 years (range: 20 - 70 years). The most common location of the tumor was the tail of the pancreas (n = 4; 45%). Surgery was performed in all the cases; five cases underwent video-assisted laparoscopy and spleen-preserving distal pancreatectomy was the technique more commonly used (n = 6). Three complications were recorded: two abdominal collections due to biliary leaks were trated by percutaneous approach and the other patient presented delayed gastric emptying and required prolonged hospitalization. Conclusion: Solid pseudopapillary tumor pf the pancreas is a rare low-grade malignant neoplasm. The prognosis is favorable after surgery and laparoscopy is the preferred approach in centers with experience.Fil: Montes, Leonardo Ezequiel. Fundación Favaloro; ArgentinaFil: Alaniz, Jimena. Fundación Favaloro; ArgentinaFil: Dieguez Palacios, Andres. Fundación Favaloro; ArgentinaFil: Varela, Estanislao. Fundación Favaloro; ArgentinaFil: Lobos, Fernando D.. Fundación Favaloro; ArgentinaFil: Fernandez, Florencia M.. Fundación Favaloro; ArgentinaFil: Farinelli, Pablo. Fundación Favaloro; ArgentinaFil: Ramisch, Diego. Fundación Favaloro; ArgentinaFil: Barros Schelotto, Pablo. Fundación Favaloro; ArgentinaFil: Gondolesi, Gabriel Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Medicina Traslacional, Trasplante y Bioingeniería. Fundación Favaloro. Instituto de Medicina Traslacional, Trasplante y Bioingeniería; Argentin

Genetic Landscape of the ACE2 Coronavirus Receptor

Background:SARS-CoV-2, the causal agent of COVID-19, enters human cells using the ACE2 (angiotensin-converting enzyme 2) protein as a receptor. ACE2 is thus key to the infection and treatment of the coronavirus. ACE2 is highly expressed in the heart and respiratory and gastrointestinal tracts, playing important regulatory roles in the cardiovascular and other biological systems. However, the genetic basis of the ACE2 protein levels is not well understood.Methods:We have conducted the largest genome-wide association meta-analysis of plasma ACE2 levels in &gt;28 000 individuals of the SCALLOP Consortium (Systematic and Combined Analysis of Olink Proteins). We summarize the cross-sectional epidemiological correlates of circulating ACE2. Using the summary statistics–based high-definition likelihood method, we estimate relevant genetic correlations with cardiometabolic phenotypes, COVID-19, and other human complex traits and diseases. We perform causal inference of soluble ACE2 on vascular disease outcomes and COVID-19 severity using mendelian randomization. We also perform in silico functional analysis by integrating with other types of omics data.Results:We identified 10 loci, including 8 novel, capturing 30% of the heritability of the protein. We detected that plasma ACE2 was genetically correlated with vascular diseases, severe COVID-19, and a wide range of human complex diseases and medications. An X-chromosome cis–protein quantitative trait loci–based mendelian randomization analysis suggested a causal effect of elevated ACE2 levels on COVID-19 severity (odds ratio, 1.63 [95% CI, 1.10–2.42]; P=0.01), hospitalization (odds ratio, 1.52 [95% CI, 1.05–2.21]; P=0.03), and infection (odds ratio, 1.60 [95% CI, 1.08–2.37]; P=0.02). Tissue- and cell type–specific transcriptomic and epigenomic analysis revealed that the ACE2 regulatory variants were enriched for DNA methylation sites in blood immune cells.Conclusions:Human plasma ACE2 shares a genetic basis with cardiovascular disease, COVID-19, and other related diseases. The genetic architecture of the ACE2 protein is mapped, providing a useful resource for further biological and clinical studies on this coronavirus receptor

Progress from ASDEX Upgrade experiments in preparing the physics basis of ITER operation and DEMO scenario development

An overview of recent results obtained at the tokamak ASDEX Upgrade (AUG) is given. A work flow for predictive profile modelling of AUG discharges was established which is able to reproduce experimental H-mode plasma profiles based on engineering parameters only. In the plasma center, theoretical predictions on plasma current redistribution by a dynamo effect were confirmed experimentally. For core transport, the stabilizing effect of fast ion distributions on turbulent transport is shown to be important to explain the core isotope effect and improves the description of hollow low-Z impurity profiles. The L-H power threshold of hydrogen plasmas is not affected by small helium admixtures and it increases continuously from the deuterium to the hydrogen level when the hydrogen concentration is raised from 0 to 100%. One focus of recent campaigns was the search for a fusion relevant integrated plasma scenario without large edge localised modes (ELMs). Results from six different ELM-free confinement regimes are compared with respect to reactor relevance: ELM suppression by magnetic perturbation coils could be attributed to toroidally asymmetric turbulent fluctuations in the vicinity of the separatrix. Stable improved confinement mode plasma phases with a detached inner divertor were obtained using a feedback control of the plasma β. The enhanced D α H-mode regime was extended to higher heating power by feedback controlled radiative cooling with argon. The quasi-coherent exhaust regime was developed into an integrated scenario at high heating power and energy confinement, with a detached divertor and without large ELMs. Small ELMs close to the separatrix lead to peeling-ballooning stability and quasi continuous power exhaust. Helium beam density fluctuation measurements confirm that transport close to the separatrix is important to achieve the different ELM-free regimes. Based on separatrix plasma parameters and interchange-drift-Alfvén turbulence, an analytic model was derived that reproduces the experimentally found important operational boundaries of the density limit and between L- and H-mode confinement. Feedback control for the X-point radiator (XPR) position was established as an important element for divertor detachment control. Stable and detached ELM-free phases with H-mode confinement quality were obtained when the XPR was moved 10 cm above the X-point. Investigations of the plasma in the future flexible snow-flake divertor of AUG by means of first SOLPS-ITER simulations with drifts activated predict beneficial detachment properties and the activation of an additional strike point by the drifts