71 research outputs found
Cytoplasmic signaling in the control of mitochondrial uproar?
The concept of a pre-emptive strike as a good means to prevent greater harm may be frequently over-stressed in daily life. However, biological systems in a homeostatic balance are prepared to withstand a certain degree of hostile fire by rather passive means. This also applies to the maintenance of cell survival, where a plethora of protective proteins provide safeguard against erroneous activation of death pathways. Apart from these mechanisms active processes are also essential for the maintenance of cellular homeostasis, commonly referred to as survival signaling. Frequently their targets may be mitochondrial, assuring organelle integrity, which is essential for continued energy production and survival. Transient or permanent failures in these cellular defense strategies result in pathophysiological conditions, which manifest themselves e.g. as cancer or ischemia/reperfusion-associated organ damage
Los trastornos funcionales digestivos desde la perspectiva del Dietista-Nutricionista equipo interdisciplinar
III Congreso de Alimentación, Nutrición y Dietética. Combinar la nutrición comunitaria y personalizada: nuevos retos
Identification of molecular markers of delayed graft function based on the regulation of biological ageing
Introduction:
Delayed graft function is a prevalent clinical problem in renal transplantation for which there is no objective system to predict occurrence in advance. It can result in a significant increase in the necessity for hospitalisation post-transplant and is a significant risk factor for other post-transplant complications.
Methodology:
The importance of microRNAs (miRNAs), a specific subclass of small RNA, have been clearly demonstrated to influence many pathways in health and disease. To investigate the influence of miRNAs on renal allograft performance post-transplant, the expression of a panel of miRNAs in pre-transplant renal biopsies was measured using qPCR. Expression was then related to clinical parameters and outcomes in two independent renal transplant cohorts.
Results:
Here we demonstrate, in two independent cohorts of pre-implantation human renal allograft biopsies, that a novel pre-transplant renal performance scoring system (GRPSS), can determine the occurrence of DGF with a high sensitivity (>90%) and specificity (>60%) for donor allografts pre-transplant, using just three senescence associated microRNAs combined with donor age and type of organ donation.
Conclusion:
These results demonstrate a relationship between pre-transplant microRNA expression levels, cellular biological ageing pathways and clinical outcomes for renal transplantation. They provide for a simple, rapid quantitative molecular pre-transplant assay to determine post-transplant allograft function and scope for future intervention. Furthermore, these results demonstrate the involvement of senescence pathways in ischaemic injury during the organ transplantation process and an indication of accelerated bio-ageing as a consequence of both warm and cold ischaemia
Insights from a Murine Aortic Transplantation Model
Transplant vasculopathy (TV) represents a major obstacle to long-term graft
survival and correlates with severity of ischemia reperfusion injury (IRI).
Donor administration of the nitric oxide synthases (NOS) co-factor
tetrahydrobiopterin has been shown to prevent IRI. Herein, we analysed whether
tetrahydrobiopterin is also involved in TV development. Using a fully
allogeneic mismatched (BALB/c to C57BL/6) murine aortic transplantation model
grafts subjected to long cold ischemia time developed severe TV with intimal
hyperplasia (α-smooth muscle actin positive cells in the neointima) and
endothelial activation (increased P-selectin expression). Donor pretreatment
with tetrahydrobiopterin significantly minimised these changes resulting in
only marginal TV development. Severe TV observed in the non-treated group was
associated with increased protein oxidation and increased occurrence of
endothelial NOS monomers in the aortic grafts already during graft
procurement. Tetrahydrobiopterin supplementation of the donor prevented all
these early oxidative changes in the graft. Non-treated allogeneic grafts
without cold ischemia time and syngeneic grafts did not develop any TV. We
identified early protein oxidation and impaired endothelial NOS homodimer
formation as plausible mechanistic explanation for the crucial role of IRI in
triggering TV in transplanted aortic grafts. Therefore, targeting endothelial
NOS in the donor represents a promising strategy to minimise TV
Reassessment of Relevance and Predictive Value of Parameters Indicating Early Graft Dysfunction in Liver Transplantation: AST Is a Weak, but Bilirubin and INR Strong Predictors of Mortality
Introduction: Early graft dysfunction (EAD) complicates liver transplantation (LT). The
aim of this analysis was to discriminate between the weight of each variable as for its
predictive value toward patient and graft survival.
Methods: We reviewed all LT performed at the Medical University of Innsbruck between
2007 and 2018. EAD was recorded when one of the following criteria was present: (i)
aspartate aminotransferase (AST) levels >2,000 IU/L within the first 7 days, (ii) bilirubin
levels 10mg/dL or (iii) international normalized ratio (INR) 1.6 on postoperative day 7.
Results: Of 616 LT, 30.7% developed EAD. Patient survival did not differ significantly
(P = 0.092; log rank-test = 2.87), graft survival was significantly higher in non-EAD
patients (P = 0.008; log rank-test = 7.13). Bilirubin and INR on postoperative day 7 were
identified as strong mortality predictors (Bilirubin HR = 1.71 [1.34, 2.16]; INR HR = 2.69
[0.51, 14.31]), in contrast to AST (HR = 0.91 [0.75, 1.10]). Similar results were achieved
for graft loss estimation. A comparison with the Model for Early Allograft Function (MEAF)
and the Liver Graft Assessment Following Transplantation (L-GrAFT) score identified a
superior discrimination potential but lower specificity.
Conclusion: Contrarily to AST, bilirubin and INR have strong predictive capacity for
patient and graft survival. This fits well with the understanding, that bile duct injury and
deprivation of synthetic function rather than hepatocyte injury are key factors in LT
Una propuesta problematizadora en la formación docente del Profesorado Universitario de Educación Física de la Universidad de Luján
La presente ponencia sintetiza la propuesta de enseñanza que desarrollamos como equipo docente en el ámbito de la formación docente en Educación Física dentro de la Universidad Nacional de Luján. El trabajo desarrollado se ancla en el doble propósito que traza la asignatura consistente en brindar algunas herramientas a los estudiantes ingresantes para acercarse a la reflexión sobre la enseñanza y, a su vez, a las características del estudio universitario. Asumimos esta tarea desde una perspectiva crítica y problematizadora de la educación, haciendo consciente la dimensión éticopolítica de la enseñanza y buscando lograr una coherencia entre las intervenciones como equipo y la búsqueda por la transformación social. Tarea que no está exenta de debates ni dificultades pero que supone una constante reflexión sobre lo que se hace para garantizar a nuestrxs estudiantes la apropiación de conocimientos y prácticas ligadas al compromiso con lxs otrxs.Mesa 16: Educación física y educación superiorFacultad de Humanidades y Ciencias de la Educació
El diseño curricular del PUEF-UNLu: entre el conocimiento disciplinar y el conocimiento didáctico del contenido para la formación de profesores en Educación Física
En el marco de un proyecto de investigación del Equipo Docente de la asignatura de Teorías de la Enseñanza y el currículo dentro del Profesorado Universitario en Educación Física comenzamos a intentar comprender y describir de qué modo se articulan en la actualidad los conocimientos didácticos del contenido y los conocimientos disciplinares en el Plan de Estudios del Profesorado Universitario de Educación Física de la Universidad Nacional de Luján (PUEF-UNLu). De este modo, dicha problemática gira en torno a algunos interrogantes clave: ¿De qué manera queda plasmado en el texto curricular la relación entre los diferentes tipos de conocimientos propios de los campos de saber que conforman la Educación Física para la Formación Docente? ¿Existe un predominio de conocimientos disciplinares por sobre el conocimientos didácticos del contenido? ¿Qué tensiones surgen en esta articulación? ¿Es posible dar cuenta de la permanencia de una tradición consolidada en la Formación Docente a nivel del Plan de Estudios? ¿Qué implicancias podría tener esto para el desarrollo curricular de las asignaturas?Facultad de Humanidades y Ciencias de la Educació
Treatment characteristics and outcomes of pure Acinar cell carcinoma of the pancreas - A multicentric European study on radically resected patients
Background: Acinar cell carcinomas (ACC) belong to the exocrine pancreatic malignancies. Due to their rarity, there is no consensus regarding treatment strategies for resectable ACC. Methods: This is a retrospective multicentric study of radically resected pure pancreatic ACC. Primary endpoints were overall survival (OS) and disease-free survival (DFS). Further endpoints were oncologic outcomes related to tumor stage and therapeutic protocols. Results: 59 patients (44 men) with a median age of 64 years were included. The median tumor size was 45.0 mm. 61.0% were pT3 (n = 36), nodal positivity rate was 37.3% (n = 22), and synchronous distant metastases were present in 10.1% of the patients (n = 6). 5-Years OS was 60.9% and median DFS 30 months. 24 out of 31 recurred systemically (n = 18 only systemic, n = 6 local and systemic). Regarding TNM-staging, only the N2-stage negatively influenced OS and DFS (p = 0.004, p = 0.001). Adjuvant treatment protocols (performed in 62.7%) did neither improve OS (p = 0.542) nor DFS (p = 0.159). In 9 cases, radical resection was achieved following neoadjuvant therapy. Discussion: Radical surgery is currently the mainstay for resectable ACC, even for limited metastatic disease. Novel (neo)adjuvant treatment strategies are needed, since current systemic therapies do not result in a clear survival benefit in the perioperative setting
Investigation of a nonsense mutation located in the complex KIV-2 copy number variation region of apolipoprotein(a) in 10,910 individuals
Background
The concentrations of the highly atherogenic lipoprotein(a) [Lp(a)] are mainly genetically determined by the LPA gene locus. However, up to 70% of the coding sequence is located in the complex so-called kringle IV type 2 (KIV-2) copy number variation, a region hardly accessible by common genotyping and sequencing technologies. Despite its size, little is known about genetic variants in this complex region. The R21X variant is a functional variant located in this region, but it has never been analyzed in large cohorts.
Methods
We typed R21X in 10,910 individuals from three European populations using a newly developed high-throughput allele-specific qPCR assay. R21X allelic location was determined by separating the LPA alleles using pulsed-field gel electrophoresis (PFGE) and typing them separately. Using GWAS data, we identified a proxy SNP located outside of the KIV-2. Linkage disequilibrium was determined both statistically and by long-range haplotyping using PFGE. Worldwide frequencies were determined by reanalyzing the sequencing data of the 1000 Genomes Project with a dedicated pipeline.
Results
R21X carriers (frequency 0.016–0.021) showed significantly lower mean Lp(a) concentrations (− 11.7 mg/dL [− 15.5; − 7.82], p = 3.39e−32). The variant is located mostly on medium-sized LPA alleles. In the 1000 Genome data, R21X mostly occurs in Europeans and South Asians, is absent in Africans, and shows varying frequencies in South American populations (0 to 0.022). Of note, the best proxy SNP was another LPA null mutation (rs41272114, D′ = 0.958, R2 = 0.281). D′ was very high in all 1000G populations (0.986–0.996), although rs41272114 frequency varies considerably (0–0.182). Co-localization of both null mutations on the same allele was confirmed by PFGE-based long-range haplotyping.
Conclusions
We performed the largest epidemiological study on an LPA KIV-2 variant so far, showing that it is possible to assess LPA KIV-2 mutations on a large scale. Surprisingly, in all analyzed populations, R21X was located on the same haplotype as the splice mutation rs41272114, creating “double-null” LPA alleles. Despite being a nonsense variant, the R21X status does not provide additional information beyond the rs41272114 genotype. This has important implications for studies using LPA loss-of-function mutations as genetic instruments and emphasizes the complexity of LPA genetics
E-AHPBA-ESSO-ESSR Innsbruck consensus guidelines for preoperative liver function assessment before hepatectomy
Background
Posthepatectomy liver failure (PHLF) contributes significantly to morbidity and mortality after liver surgery. Standardized assessment of preoperative liver function is crucial to identify patients at risk. These European consensus guidelines provide guidance for preoperative patient assessment.
Methods
A modified Delphi approach was used to achieve consensus. The expert panel consisted of hepatobiliary surgeons, radiologists, nuclear medicine specialists, and hepatologists. The guideline process was supervised by a methodologist and reviewed by a patient representative. A systematic literature search was performed in PubMed/MEDLINE, the Cochrane library, and the WHO International Clinical Trials Registry. Evidence assessment and statement development followed Scottish Intercollegiate Guidelines Network methodology.
Results
Based on 271 publications covering 4 key areas, 21 statements (at least 85 per cent agreement) were produced (median level of evidence 2− to 2+). Only a few systematic reviews (2++) and one RCT (1+) were identified. Preoperative liver function assessment should be considered before complex resections, and in patients with suspected or known underlying liver disease, or chemotherapy-associated or drug-induced liver injury. Clinical assessment and blood-based scores reflecting liver function or portal hypertension (for example albumin/bilirubin, platelet count) aid in identifying risk of PHLF. Volumetry of the future liver remnant represents the foundation for assessment, and can be combined with indocyanine green clearance or LiMAx® according to local expertise and availability. Functional MRI and liver scintigraphy are alternatives, combining FLR volume and function in one examination.
Conclusion
These guidelines reflect established methods to assess preoperative liver function and PHLF risk, and have uncovered evidence gaps of interest for future research.publishedVersio
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