Systematic Identification of Genes that Regulate Neuronal Wiring in the Drosophila Visual System

Forward genetic screens in model organisms are an attractive means to identify those genes involved in any complex biological process, including neural circuit assembly. Although mutagenesis screens are readily performed to saturation, gene identification rarely is, being limited by the considerable effort generally required for positional cloning. Here, we apply a systematic positional cloning strategy to identify many of the genes required for neuronal wiring in the Drosophila visual system. From a large-scale forward genetic screen selecting for visual system wiring defects with a normal retinal pattern, we recovered 122 mutations in 42 genetic loci. For 6 of these loci, the underlying genetic lesions were previously identified using traditional methods. Using SNP-based mapping approaches, we have now identified 30 additional genes. Neuronal phenotypes have not previously been reported for 20 of these genes, and no mutant phenotype has been previously described for 5 genes. The genes encode a variety of proteins implicated in cellular processes such as gene regulation, cytoskeletal dynamics, axonal transport, and cell signalling. We conducted a comprehensive phenotypic analysis of 35 genes, scoring wiring defects according to 33 criteria. This work demonstrates the feasibility of combining large-scale gene identification with large-scale mutagenesis in Drosophila, and provides a comprehensive overview of the molecular mechanisms that regulate visual system wiring

Maternal plasma levels of oxytocin during physiological childbirth - a systematic review with implications for uterine contractions and central actions of oxytocin

Oxytocin is a key hormone in childbirth, and synthetic oxytocin is widely administered to induce or speed labour. Due to lack of synthetized knowledge, we conducted a systematic review of maternal plasma levels of oxytocin during physiological childbirth, and in response to infusions of synthetic oxytocin, if reported in the included studies. An a priori protocol was designed and a systematic search was conducted in PubMed, CINAHL, and PsycINFO in October 2015. Search hits were screened on title and abstract after duplicates were removed (n = 4039), 69 articles were examined in full-text and 20 papers met inclusion criteria. As the articles differed in design and methodology used for analysis of oxytocin levels, a narrative synthesis was created and the material was categorised according to effects. Basal levels of oxytocin increased 3-4-fold during pregnancy. Pulses of oxytocin occurred with increasing frequency, duration, and amplitude, from late pregnancy through labour, reaching a maximum of 3 pulses/10 min towards the end of labour. There was a maximal 3- to 4-fold rise in oxytocin at birth. Oxytocin pulses also occurred in the third stage of labour associated with placental expulsion. Oxytocin peaks during labour did not correlate in time with individual uterine contractions, suggesting additional mechanisms in the control of contractions. Oxytocin levels were also raised in the cerebrospinal fluid during labour, indicating that oxytocin is released into the brain, as well as into the circulation. Oxytocin released into the brain induces beneficial adaptive effects during birth and postpartum. Oxytocin levels following infusion of synthetic oxytocin up to 10 mU/min were similar to oxytocin levels in physiological labour. Oxytocin levels doubled in response to doubling of the rate of infusion of synthetic oxytocin. Plasma oxytocin levels increase gradually during pregnancy, and during the first and second stages of labour, with increasing size and frequency of pulses of oxytocin. A large pulse of oxytocin occurs with birth. Oxytocin in the circulation stimulates uterine contractions and oxytocin released within the brain influences maternal physiology and behaviour during birth. Oxytocin given as an infusion does not cross into the mother's brain because of the blood brain barrier and does not influence brain function in the same way as oxytocin during normal labour does

Slutrapport Förstudie Brantare

Förstudie Brantare är en förstudie vars syfte har varit att identifiera forskningsbehov som är relevanta för att kunna genomföra en meningsfull implementering av brantare inflygningsvinkel som bullerreducerande åtgärd. Detta har gjorts genom att: 1. Identifiera vilka variabler som är avgörande för att kunna tillämpa brantare inflygningsvinkel. Detta relaterat till flygoperativa aspekter och begränsningar. T ex faktorer såsom flygplanens egenskaper, vindriktning och styrka. Andra relevanta faktorer kan vara sikt, moln, nederbörd, inflygningsvinkel (autolandsystembegränsningar och inflygningsljusvinkel), trafikintensitet, flygplanskategori (Light, Medium, Heavy) etc. 2. Identifiera variabler som är avgörande för den potentiellt bullerreducerande effekten av brantare inflygningsvinkel. Detta är mer relaterat till hållbarhetsaspekter som bullergenerering samt spridning och exempelvis bränsleförbrukning (miljö och operativa kostnader). Målet har varit att, baserat på det identifierade forskningsbehovet, skapa ingångsvärden till ett kommande huvudprojekt Brantare. Huvudprojektets syfte kommer sedan att vara att ge kunskap om de flygoperationella aspekterna och effekterna av inflygning med glidbanevinklar brantare än vad som vanligtvis används av flygplan vid inflygning till en flygplats. Kunskap kommer då att erhållas huruvida piloters sätt att flyga innebär möjligheter eller begränsningar till att reducera buller i praktiken, och vilka möjligheter och begränsningar detta är. En brantare inflygningsvinkel minskar i teorin bullerpåverkan från ankommande flygplan till en flygplats genom att avståndet mellan bullerkällan och det störda området på marken ökas. Flygoperativt kommer troligtvis en förändring av glidbanevinkeln innebära en annorlunda hantering av flygplanets läges- och rörelseenergi. Effekten skulle kunna innebära att ett förändrat sätt att flyga då kan medföra nya mönster av bullerspridning vid inflygningen. Detta skulle kunna förta den önskade effekten och till och med kunna få direkt motsatt effekt för vissa områden på marken. I denna förstudie, som även lett fram till en forskningsansökan, har piloters agerande vid inflygning med brantare inflygningsvinkel konstaterats vara ett område som inte studerats särskilt ofta trots att forskning har efterfrågats. För att om möjligt kunna få ett tillräckligt stort flygoperativt underlag att arbeta med kommer därför en viktig del i huvudprojektet Brantare vara användningen av data från färdskrivare i kommersiella flygplan. Denna data innehåller betydligt mer information än exempelvis radardata. Genom att därur extrahera data rörande piloters agerande och korrigera den fysiska inflygningsvinkeln med vinddata, kan piloternas agerande studeras för en ekvivalent glidbana som motsvarar den glidbana som skulle ha flugits om det varit vindstilla. Förstudien har också konstaterat att samverkan med andra möjliga CSA-finansierade projekt, primärt SAFT, kan skapa synergieffekter och därmed ge en ökad förståelse för hur det potentiellt förändrade flygoperativa beteendet kopplat till en förändrad glidbanevinkel kan förväntas påverka bullerspridningen i varje punkt längs en inflygning och hur bullerspridningen kan förändras (t.ex. minska i ett område men öka i ett annat) med hänsyn till aktuell vind och faktiskt glidbanevinkel.CSA ULLA Undersökningar medelst Ljudmätningar vid Landningar på Arland

Use of correct or nominal water velocities in Morison\u27s equation

A laboratory experiment has been performed to evaluate the drag and inertia coefficients in the Morison Equation. The total waveforce, the pressure distribution and the kinematics of steep waves have been measured. The experimental arrangement is described and the data processing is sketched. The technique for measuring the velocity is descrbed in detail.It is shown that it is important to use the same type of velocity in design as is used in the experiments from which the coefficients are evaluated. It was also found that the best choice of wave theory from five investgated theories for most cases is th fifth order theory. For shallow water the best choice is the cnoidal theory

Slutrapport projekt Brantare

Syftet har specifikt varit att ge kunskap om de flygoperationella aspekterna och effekterna av inflygning med glidbanevinklar något större än vad som normalt används av flygplan vid inflygning till en flygplats. Att till ämpa en större glidbanevinkel minskar i teorin buller påverkan från ankommande flygplan genom att avståndet mellan buller källan och det störda om rådet på marken ökar. Flygoperativt inn ebär detta en brantare glidbana och således också en annorlunda hantering av flygplanets läges- och rörelseenergi. Ett förändrat sätt att flyga kan då med föra nya mönster av bullerspridning vid inflygningen.Flera faktorer bidrar till att det är svårt att genomföra faktiska försök med brantare glidbana och därmed studera piloters operationella beteende. Svårigheter kan t.ex. vara brist på inflygningar med brantare glidbanevinkel eller problem att praktiskt genomföra experimentflygningar med tempo rär inflygningsprocedur med hänsyn till annan trafik, krav på trafikavveckling etc. Projektets idé är följaktligen att använda faktiska vinddata insamlade vid normala inflygningar med 3,0° glidbanevinkel och att använda dessa data för att räkna ut vad en motsvarande glidbanevinkel hade varit om det hade varit vindstilla. Därigenom kan en brantare inflygning approximeras när vinddata indikerar medvind under inflygningen, och därmed kan piloters operationella beteende vid en brantare inflygning studeras. Denna om räknade glidbanevinkel, baserad på faktisk vinddata, kallas här för ekvivalent nollvindsglidbana.Projektarbetet har ut förts i flera steg: utveckling av beräkningsmetodik för ekvivalent nollvindsglidbana; insamling, hantering och analys av relevant data, både flygdata och vinddata, samt validering av metod och resultat. För projektet har flera metoder använts. Övergripande har det varit stort fokus på piloter som deltagit i ett seminarium och intervjuer för både utveckling av modell, metod och uppföljning av resultat rörande ekvivalent nollvindsglidbana. Ett av projektets resultat är att ekvivalent nollvindsglidbana kan användas för att approximera piloters operationella beteende vid brantare glidbana. När den valda metoden med ekvivalent nollvindsglidbana tillämpas på data så konstateras att, om metoden vore direkt överförbar på verkliga inflygningar, så skulle piloterna fälla ut både land ningsställ och det sista steget klaff, landningsklaff, på en högre höjd vid brantare inflygningar. På grund av den förändrade geometrin med en brantare glidbanevinkel skulle detta dock ske närmare landningsbanan för inflygningar med en brantare glidbana än för inflygningar med 3,0° glidbanevinkel.Projektet Brantare har ökat kunskapen om hur flygoperativt beteende ändras vid ökad glidbanevinkel. Detta kan förändra bullerexponering runt flygplatsen. Fortsatt forskning krävs för att fastställa vilken reell förändring på buller det ändrade flygoperativa beteendet kan få.CSA BRANTAR

Mechanisms of basal and cytokine-induced uptake of glucose in normal human eosinophils: relation to apoptosis

To access publisher full text version of this article. Please click on the hyperlink in Additional Link fieldA link between glucose transport and apoptosis was suggested. We studied the mechanisms of glucose transport in human eosinophils by means of the uptake of the positron emitting analogue, 18Fluoro-2-Deoxyglucose (FDG) and apoptosis by means of flow cytometry. FDG uptake was inhibited by antibodies to GLUT1, 3 and 4 and by cytochalasin B. The anti-apoptotic principles IL-5, GM-CSF, IL-3 enhanced the uptake, whereas the apoptosis-inducing principles anti-CD95 (anti-Fas) and exposure to serum-coated Sephadex particles caused a reduction. Also TNF-alpha enhanced the uptake. Other cytokines such as IL-2, IL-4, IL-8, RANTES and MCP-3 had no effect on the glucose uptake. 2-Deoxyglucose, antibodies to GLUT4 and CD95 induced apoptosis. The basal FDG-uptake was unaffected by PKC inhibitors Ro-31-8220, Gö-6983 and Gö-6976, whereas the latter inhibited the IL-5-enhanced uptake possibly due to the inhibition of PKC(mu). Protein tyrosine kinase and PI-3 kinase inhibitors inhibited IL-5-enhanced FDG-uptake only. In contrast MEK inhibitors inhibited the basal uptake only. Inhibitors of p38 MAPkinase inhibited both basal and IL-5 enhanced uptake. We conclude that glucose uptake in eosinophils is governed by specific intracellular mechanisms involving mobilization of GLUTs, Ca2+ and the activation of the MAP kinase pathway and that the IL-5-enhanced uptake uniquely seems to involve PKC(mu) activity. Our results suggest a close link between apoptosis and glucose transport in human eosinophils

Variablity in vastus lateralis fiber type distribution, fiber size and myonuclear content along and between the legs.

Human skeletal muscle characteristics such as fiber type composition, fiber size and myonuclear content are widely studied in clinical and sports related contexts. Being aware of the methodological and biological variability of the characteristics is a critical aspect in study design and outcome interpretation, but comprehensive data on the variability of morphological features in human skeletal muscle is currently limited. Accordingly, in the present study, m. vastus lateralis biopsies (10 per subject) from young and healthy individuals, collected in a systematic manner, were analyzed for various characteristics using immunohistochemistry (n=7) and SDS-PAGE (n=25). None of the analyzed parameters; fiber type % (FT%), type I and II CSA (fCSA), percentage fiber type area (fCSA%), myosin heavy chain composition (MyHC%), type IIX content, myonuclear content or myonuclear domain varied in a systematic manner longitudinally along the muscle or between the two legs. The average within subject coefficient of variation for FT%, fCSA, fCSA%, and MyHC% ranged between 13-18%, but was only 5% for fiber specific myonuclear content, which reduced the variability for myonuclear domain size to 11-12%. Pure type IIX fibers and type IIX MyHC were randomly distributed and present in <24% of the analyzed samples, with the average content being 0.1 and 1.1%, respectively. In conclusion, leg or longitudinal orientation does not seem to be an important aspect to consider when investigating human vastus lateralis characteristics. However, single muscle biopsies should preferably not be used when studying fiber type and fiber size related aspects given the notable sample to sample variability

Maternal plasma levels of oxytocin during physiological childbirth – a systematic review with implications for uterine contractions and central actions of oxytocin

Background:Oxytocin is a key hormone in childbirth, and synthetic oxytocin is widely administered to induce orspeed labour. Due to lack of synthetized knowledge, we conducted a systematic review of maternal plasma levelsof oxytocin during physiological childbirth, and in response to infusions of synthetic oxytocin, if reported in theincluded studies.Methods:An a priori protocol was designed and a systematic search was conducted in PubMed, CINAHL, andPsycINFO in October 2015. Search hits were screened on title and abstract after duplicates were removed (n=4039), 69 articles were examined in full-text and 20 papers metinclusion criteria. As the articles differed in designand methodology used for analysis of oxytocin levels,a narrative synthesis was created and the material wascategorised according to effects.Results:Basal levels of oxytocin increased 3–4-fold during pregnancy. Pulses of oxytocin occurred with increasingfrequency, duration, and amplitude, from late pregnancy through labour, reaching a maximum of 3 pulses/10 mintowards the end of labour. There was a maximal 3- to 4-fold rise in oxytocin at birth. Oxytocin pulses also occurred inthe third stage of labour associated with placental expulsion. Oxytocin peaks during labour did not correlate in timewith individual uterine contractions, suggesting additional mechanisms in the control of contractions. Oxytocin levelswere also raised in the cerebrospinal fluid during labour, indicating that oxytocin is released into the brain, as well asinto the circulation. Oxytocin released into the brain induces beneficial adaptive effects during birth and postpartum.Oxytocin levels following infusion of synthetic oxytocin up to 10 mU/min were similar to oxytocin levels inphysiological labour. Oxytocin levels doubled in response to doubling of the rate of infusion of synthetic oxytocin.Conclusions:Plasma oxytocin levels increase gradually during pregnancy, and during the first and second stages oflabour, with increasing size and frequency of pulses of oxytocin. A large pulse of oxytocin occurs with birth. Oxytocin inthe circulation stimulates uterine contractions and oxytocin released within the brain influences maternal physiologyand behaviour during birth. Oxytocin given as an infusion does not cross into the mother’s brain because of the bloodbrain barrier and does not influence brain function in the same way as oxytocin during normal labour does