The Lysosomal Calcium Channel TRPML1 Maintains Mitochondrial Fitness in NK Cells through Interorganelle Cross-Talk

Cytotoxic lymphocytes eliminate cancer cells through the release of lytic granules, a specialized form of secretory lysosomes. This compartment is part of the pleomorphic endolysosomal system and is distinguished by its highly dynamic Ca2+ signaling machinery. Several transient receptor potential (TRP) calcium channels play essential roles in endolysosomal Ca2+ signaling and ensure the proper function of these organelles. In this study, we examined the role of TRPML1 (TRP cation channel, mucolipin subfamily, member 1) in regulating the homeostasis of secretory lysosomes and their cross-talk with mitochondria in human NK cells. We found that genetic deletion of TRPML1, which localizes to lysosomes in NK cells, led to mitochondrial fragmentation with evidence of collapsed mitochondrial cristae. Consequently, TRPML1-/- NK92 (NK92ML1-/-) displayed loss of mitochondrial membrane potential, increased reactive oxygen species stress, reduced ATP production, and compromised respiratory capacity. Using sensitive organelle-specific probes, we observed that mitochondria in NK92ML1-/- cells exhibited evidence of Ca2+ overload. Moreover, pharmacological activation of the TRPML1 channel in primary NK cells resulted in upregulation of LC3-II, whereas genetic deletion impeded autophagic flux and increased accumulation of dysfunctional mitochondria. Thus, TRPML1 impacts autophagy and clearance of damaged mitochondria. Taken together, these results suggest that an intimate interorganelle communication in NK cells is orchestrated by the lysosomal Ca2+ channel TRPML1

Late incidence and recurrence of new-onset atrial fibrillation after isolated surgical aortic valve replacement

Atrial fibrillation (AF) is a common complication after cardiac surgery. More knowledge is needed about long-term AF recurrence and adverse outcomes related to new-onset AF (NOAF) during the index hospitalization.A total of 1073 patients underwent isolated surgical aortic valve replacement at the 4 participating hospitals (2002-2014). After the exclusion of patients with a history of any preoperative AF, the final study population included 529 patients in the bioprosthetic and 253 patients in the mechanical valve prosthesis cohort. Median follow-up time was 5.4 (interquartile range, 3.4-8.2) years in the combined cohort.Altogether 333 (42.6%) patients had in-hospital NOAF and 250 (32.0%) AF after hospital discharge. In the mechanical cohort, 64 (25.3%) experienced in-hospital NOAF and 74 (29.2%) AF after hospital discharge, whereas in the bioprosthetic cohort, 269 (50.9%) patients had in-hospital NOAF and 176 (33.3%) AF after hospital discharge. Patients with NOAF during the index hospital stay had a multifold risk of AF after hospital discharge in the combined cohort (hazard ratio [HR], 3.68; 95% confidence interval [CI], 2.82-4.81; P P P P = .025) and bioprosthetic (HR, 1.63; 95% CI, 1.17-2.28; P = .004) valve prosthesis cohorts.NOAF during the index hospitalization is associated with a 2- to 4-fold risk of later AF and 1.6- to 2.0-fold risk of all-cause mortality after mechanical and bioprosthetic surgical aortic valve replacement.</p

Testing the theory of immune selection in cancers that break the rules of transplantation

Modification of cancer cells likely to reduce their immunogenicity, including loss or down-regulation of MHC molecules, is now well documented and has become the main support for the concept of immune surveillance. The evidence that these modifications, in fact, result from selection by the immune system is less clear, since the possibility that they may result from reorganized metabolism associated with proliferation or from cell de-differentiation remains. Here, we (a) survey old and new transplantation experiments that test the possibility of selection and (b) survey how transmissible tumours of dogs and Tasmanian devils provide naturally evolved tests of immune surveillance

Network Analysis of Differential Expression for the Identification of Disease-Causing Genes

Genetic studies (in particular linkage and association studies) identify chromosomal regions involved in a disease or phenotype of interest, but those regions often contain many candidate genes, only a few of which can be followed-up for biological validation. Recently, computational methods to identify (prioritize) the most promising candidates within a region have been proposed, but they are usually not applicable to cases where little is known about the phenotype (no or few confirmed disease genes, fragmentary understanding of the biological cascades involved). We seek to overcome this limitation by replacing knowledge about the biological process by experimental data on differential gene expression between affected and healthy individuals. Considering the problem from the perspective of a gene/protein network, we assess a candidate gene by considering the level of differential expression in its neighborhood under the assumption that strong candidates will tend to be surrounded by differentially expressed neighbors. We define a notion of soft neighborhood where each gene is given a contributing weight, which decreases with the distance from the candidate gene on the protein network. To account for multiple paths between genes, we define the distance using the Laplacian exponential diffusion kernel. We score candidates by aggregating the differential expression of neighbors weighted as a function of distance. Through a randomization procedure, we rank candidates by p-values. We illustrate our approach on four monogenic diseases and successfully prioritize the known disease causing genes

Mucin Dynamics in Intestinal Bacterial Infection

Bacterial gastroenteritis causes morbidity and mortality in humans worldwide. Murine Citrobacter rodentium infection is a model for gastroenteritis caused by the human pathogens enteropathogenic Escherichia coli and enterohaemorrhagic E. coli. Mucin glycoproteins are the main component of the first barrier that bacteria encounter in the intestinal tract.Using Immunohistochemistry, we investigated intestinal expression of mucins (Alcian blue/PAS, Muc1, Muc2, Muc4, Muc5AC, Muc13 and Muc3/17) in healthy and C. rodentium infected mice. The majority of the C. rodentium infected mice developed systemic infection and colitis in the mid and distal colon by day 12. C. rodentium bound to the major secreted mucin, Muc2, in vitro, and high numbers of bacteria were found in secreted MUC2 in infected animals in vivo, indicating that mucins may limit bacterial access to the epithelial surface. In the small intestine, caecum and proximal colon, the mucin expression was similar in infected and non-infected animals. In the distal colonic epithelium, all secreted and cell surface mucins decreased with the exception of the Muc1 cell surface mucin which increased after infection (p<0.05). Similarly, during human infection Salmonella St Paul, Campylobacter jejuni and Clostridium difficile induced MUC1 in the colon.Major changes in both the cell-surface and secreted mucins occur in response to intestinal infection

A randomized prospective multicenter trial for stroke prevention by prophylactic surgical closure of the left atrial appendage in patients undergoing bioprosthetic aortic valve surgery--LAA-CLOSURE trial protocol

Patients undergoing surgical aortic valve replacement (SAVR) are at high risk for atrial fibrillation (AF) and stroke after surgery. There is an unmet clinical need to improve stroke prevention in this patient population. The LAA-CLOSURE trial aims to assess the efficacy and safety of prophylactic surgical closure of the left atrial appendage for stroke and cardiovascular death prevention in patients undergoing bioprosthetic SAVR. This randomized, open-label, prospective multicenter trial will enroll 1,040 patients at 13 European sites. The primary endpoint is a composite of cardiovascular mortality, stroke and systemic embolism at 5 years. Secondary endpoints include cardiovascular mortality, stroke, systemic embolism, bleed fulfilling academic research consortium (BARC) criteria, hospitalization for decompensated heart failure and health economic evaluation. Sample size is based on 30% risk reduction in time to event analysis of primary endpoint. Prespecified reports include 30-daysafety analysis focusing on AF occurrence and short-term outcomes and interim analyses at 1 and 3 years for primary and secondary outcomes. Additionally, substudies will be performed on the completeness of the closure using transesophageal echocardiography/cardiac computed tomography and long-term ECG recording at one year after the operation. (Am Heart J 2021;237:127-134.

Early over expression of messenger RNA for multiple genes, including insulin, in the Pancreatic Lymph Nodes of NOD mice is associated with Islet Autoimmunity

<p>Abstract</p> <p>Background</p> <p>Autoimmune diabetes (T1D) onset is preceded by a long inflammatory process directed against the insulin-secreting β cells of the pancreas. Deciphering the early autoimmune mechanisms represents a challenge due to the absence of clinical signs at early disease stages. The aim of this study was to identify genes implicated in the early steps of the autoimmune process, prior to inflammation, in T1D. We have previously established that insulin autoantibodies (E-IAA) predict early diabetes onset delineating an early phenotypic check point (window 1) in disease pathogenesis. We used this sub-phenotype and applied differential gene expression analysis in the pancreatic lymph nodes (PLN) of 5 weeks old Non Obese Diabetic (NOD) mice differing solely upon the presence or absence of E-IAA. Analysis of gene expression profiles has the potential to provide a global understanding of the disease and to generate novel hypothesis concerning the initiation of the autoimmune process.</p> <p>Methods</p> <p>Animals have been screened weekly for the presence of E-IAA between 3 and 5 weeks of age. E-IAA positive or negative NOD mice at least twice were selected and RNAs isolated from the PLN were used for microarray analysis. Comparison of transcriptional profiles between positive and negative animals and functional annotations of the resulting differentially expressed genes, using software together with manual literature data mining, have been performed.</p> <p>Results</p> <p>The expression of 165 genes was modulated between E-IAA positive and negative PLN. In particular, genes coding for insulin and for proteins known to be implicated in tissue remodelling and Th1 immunity have been found to be highly differentially expressed. Forty one genes showed over 5 fold differences between the two sets of samples and 30 code for extracellular proteins. This class of proteins represents potential diagnostic markers and drug targets for T1D.</p> <p>Conclusion</p> <p>Our data strongly suggest that the immune related mechanisms taking place at this early age in the PLN, correlate with homeostatic changes influencing tissue integrity of the adjacent pancreatic tissue. Functional analysis of the identified genes suggested that similar mechanisms might be operating during pre-inflammatory processes deployed in tissues i) hosting parasitic microorganisms and ii) experiencing unrestricted invasion by tumour cells.</p

Professionalizing teaching in higher education? Understanding today’s discourse on scholarship of teaching and learning in relation to the question of widening participation within higher education

Our introduction will contextualize and give a brief background to the last decade´s discussion and request for pedagogically more skilled and trained university teachers. A discourse often framed by and named as Scholarship of Teaching and Training, SoTL. Teaching at university level has until recently, unlike most other educational institutions, not required any formal pedagogical education. In spite of often being skilled after years of teaching, the majority of Swedish university teachers still have less then the recommended ten weeks pedagogical training. The purpose of the workshop is to illuminate the emerging practice SoTL. How is it framed and who and what influences and shapes the discourse? Should it be seen as an embryo to professionalize university teaching by valuing teaching excellence? Or should it be understood as a perceived need for a new kind of pedagogical competence in order to handle the consequences of the rapid expansion of higher education during the 90´s, a change from elite to mass higher education? What actors are participating in the formulation of the need for further pedagogical training of university teachers? The teachers themselves, evaluation teams from authorities such as the Swedish National Agency for Higher Education or course giving pedagogical consultants? What arguments are put forward to legitimize these relatively new requirements? Is it focusing on students needs or is it in relation to Scholarship of Research? What definitions of pedagogical competence are formulated? To give answers to these questions are far beyond the scope of this workshop. However to scrutinize what seems to underpin the contemporary pedagogical discourse might be an important contribution to a critical analyze of present practice in HE. Relevance for Nordic Educational research: There is a need to better understand the practice Scholarship of Teaching and Learning in Higher Educatio

Akademiskt lärarskap : att initiera och examinera ett professionellt förhållningssätt

I vår presentation fokuserar vi på fyra övergripande frågor i relation till det akademiska lärarskapet: • Hur ska lärformerna vid det nya högskolepedagogiskt kursupplägg på ett adekvat och kreativt sätt ta tillvara bredden i kursdeltagarnas skiftande erfarenheter, kunskapssyn, utbildningskultur och undervisningspraxis? • Hur ska kursledningen dokumentera och utvärdera den kunskapsprocess som sker ibland såväl kursdeltagare som kursledning? • Hur kan examinationen utformas så att flertalet av kursmomenten bearbetas och diskuteras av den enskilde kursdeltagaren i relation till hans/hennes eget utbildningssammanhang? • Hur kan kursen organiseras så att det sker en återkoppling till deltagarens verksamhet på det egna området och främja utvecklandet av nätverk mellan områdena? Bakgrund Den högskolepedagogiska utbildningen vid Malmö högskola har i och med hösten 2007 fått en delvis ny inriktning och utformning. En av de faktorer som bidragit till detta är Bolognaprocessen och Högskolereformen 2007, en annan är behovet av att ge nya lärare möjlighet att inom en rimlig tidsperiod få den efterfrågade obligatoriska pedagogiska kompetensen. En tredje är att erbjuda kompetensutveckling till högskolans samtliga lärare. Den övergripande intentionen är att det nya upplägget ska bidra till att kvalitetsarbetet blir mer systematiskt integrerat i högskolans verksamhet samtidigt som det etableras en infrastruktur för det akademiska lärarskapet att utvecklas i. Förutsättningar Malmö högskolas nya högskolepedagogiska program är uppdelad i följande tre (5 hp) kurser 1) akademiskt lärarskap 2) Tematisk högskolepedagogik 3) Högskolepedagogiskt projektarbete. Den första kursen, dvs., Akademiskt lärarskap kommer här att användas som ett konkret exempel i vår diskussion av de fyra (ovannämnda) övergripande frågorna. Kursupplägget för den introducerande kursen Akademiskt lärarskap 5hp är tänkt att utveckla en bred medvetenhet om villkor och innebörder i akademiskt lärarskap. Organisatoriska som juridiska aspekter av lärarskapet ska diskuteras liksom värdegrunden i akademisk utbildning och dess roll i samhället. Under kursens gång förmedlas kunskap om forskning och erfarenhet av studenters skiftande lärstilar, liksom olika former för undervisning och studier. Dessa kunskaper ska kursdeltagarna på ett självständigt sätt tillämpa i examinationsuppgiften som bl a utmynnar i en individuell pedagogiska avsiktsförklaring. En grundläggande tanke är att mötet med kollegor från andra områden och discipliner ska främja utvecklandet av nätverk. Samtidigt som heterogeniteten bland deltagarna skapar underlag för, möjligheter till och behov av ett medvetet och artikulerat förhållningssätt kring den egna disciplinen kunskapssyn, utbildningskultur och undervisningspraxis. På så sätt skapar gruppsammansättningen konkreta förutsättningar för ett aktivt arbete med högskolans vision som sammanfattas med att Mångfald gör skillnad