140 research outputs found

    Analys av föda för vitryggig hackspett och rödlistade vedlevande skalbaggar : utvÀrdering av tre olika behandlingar

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    Den vitryggiga hackspetten har sedan 1950-talet blivit en sĂ€llsynt art i det svenska landskapet. NedgĂ„ngen beror frĂ€mst pĂ„ det moderna skogsbruket dĂ€r barrskog till stor del har ersatt blandbestĂ„nd och gammal lövskog. Hackspetten Ă€r beroende av gammal lövskog som innehĂ„ller solexponerade döda och döende trĂ€d, vilket ocksĂ„ Ă€r en livsmiljö som gynnar mĂ„nga andra arter. Den vitryggiga hackspetten fungerar som en paraplyart vilket innebĂ€r att mĂ„nga samexisterande arter skulle gynnas av Ă„terstĂ€llandet av dess livsmiljö. Idag pĂ„gĂ„r ett nationellt restaureringsprojekt för hackspetten som syftar till att bevara den biologiska mĂ„ngfalden i Sverige. Denna studie har undersökt den vitryggiga hackspettens föda och rödlistade vedlevande skalbaggar i skogar under tre olika typer av behandling: kommersiellt skötta blandskogar (C), restaurerade omrĂ„den (R) och mĂ„lhabitat för vitryggig hackspett (W). Resultat visar att för hackspettens föda finns det signifikant fler individer och högre artrikedom i W jĂ€mfört med R och C. För rödlistade arter Ă€r det signifikant fler individer i W Ă€n i R. De statistiska analyserna har inte funnit nĂ„gon signifikant skillnad mellan R och C. Orsaker till att det inte finns nĂ„gon signifikant skillnad mellan R och C studeras genom analys av andelen död ved och bestĂ„ndstyp i behandlingarna. Resultat frĂ„n analyserna visar att det inte finns nĂ„gon signifikant skillnad mellan R och C avseende bestĂ„ndstyp. FrĂ„n en 10 Ă„r tidigare studie, utförd pĂ„ samma omrĂ„den för R, har en högre abundans och artrikedom för rödlistade arter pĂ„visats jĂ€mfört med vĂ„r studies resultat. Orsak till detta kan vara att restaureringens effekt har reducerats, dĂ„ restaureringen utfördes för cirka 20 Ă„r sedan. För att bibehĂ„lla effekten av restaurering för vitryggig hackspett kan underhĂ„ll krĂ€vas för att upprĂ€tthĂ„lla tillförseln av död ved och frĂ€mja lövtrĂ€d. För att den vitryggiga hackspetten och andra arter med liknande preferenser inte ska dö ut behöver Ă„terskapande av habitat utföras pĂ„ landskapsnivĂ„.The white-backed woodpecker has since the 1950s become a rare species in the Swedish landscape. This decline is mainly due to modern forestry where coniferous forests have largely replaced mixed stands and old deciduous forests. The woodpecker is dependent on old deciduous forests containing sun-exposed dead and dying trees, which also is a habitat that benefits other species. The white-backed woodpecker acts as an umbrella species which means many coexisting species would benefit from restoration of its habitat. Today there is an ongoing national restoration project for the woodpecker that aims to preserve biological diversity in Sweden. This study takes a closer look at the white-backed woodpecker’s food and red-listed saproxylic beetles in forests undergoing three different types of treatment: commercially managed mixed forests (C), restored areas (R) and target habitats for white-backed woodpeckers (W). Results show that for the woodpecker's food, there are significantly more individuals and higher species richness in W compared to R and C. For red-listed species, there are significantly more individuals in W than in R. The statistical analysis has not found a significant difference between R and C. The reason why there is no significant difference between R and W is discussed by analyzing the proportion of dead wood and stand type in the treatments. Results from these analyzes show that there is no significant difference between R and C, regarding stand type. From a 10-year old study, performed in the same areas for R, a higher abundance and species richness of red-listed species was found compared to our study's results. The reason for this may be that the effect of the restoration has been reduced, as the restoration was carried out approximately 20 years ago. To maintain the effect of restoration for the white-backed woodpecker, further support may be required to maintain the supply of dead wood and to promote deciduous trees. In order for the white-backed woodpecker and other species with similar preferences not to become extinct, habitat restoration needs to be carried out at the landscape level

    Spatial och temporal förÀndring i nÀrvaro av vanlig tumlare (Phocoena phocoena) vid fiske med pingers i SkÀlderviken och Kullaberg

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    Ett av de större hoten mot vanlig tumlare (Phocoena phocoena) Àr bifÄngst i samband med fiske. PÄ grund av detta har effekten av akustiska kapslar (pingers) pÄ fiskenÀt undersökts i flera studier för att avgöra om bifÄngsten av tumlare kan minimeras. Sex stycken hydrofoner (C-PODs) frÄn Chelonia Limited har sedan 2015 varit utplacerade runtom Kullaberg och SkÀlderviken för att detektera tumlarnÀrvaron. I samma omrÄde har fisket med garn efter torsk och sjurygg övervakats. I fisket har pingers anvÀnts för att minska bifÄngster av tum-lare. TvÄ utplacerade C-PODS var kontroller dÄ de ansÄgs vara oberörda av fisket som pÄ-gick i omrÄdet. Fisket blev uppdelat i högt och lÄgt fisketryck beroende av hur mÄnga garn som var ute i omrÄdet och under hur lÄng tid de lÄg ute. Data som samlats in mellan 2015 och 2016 frÄn utplacerade C-PODS sammanstÀlldes i en databas dÀr variabeln DPM/timme (Detective Positive Minutes) angav om tumlare varit i nÀrheten eller ej. Syftet med studien var att undersöka huruvida variationen av tumlare i omrÄdet förÀndrades pÄ grund av fisket med pingers i omrÄdet. BÄde temporal och spatial variation i tumlarnÀrvaro kunde bekrÀftas mellan Ärstiderna under bÄde Är 2015 och 2016 samt mellan de olika C-PODSEN. Högst nÀrvaro av tumlare Äterfanns söder om halvön Kullens spets samt vid de tvÄ C-PODS som utgjorde kontrollpositioner. Skillnad i nÀrvaro mellan C-PODs pÄ samma och motsatt sida om halvön Kullen kunde urskiljas. LÀgst nÀrvaro var vid tvÄ C-PODS som lÄg mycket nÀra utlagda fiskenÀt med pingers. TumlarnÀrvaron var generellt lÀgre under de perioder dÄ fiske pÄgick för att sedan öka nÀr fisket var avslutat. Högsta tumlarnÀrvaron uppstod för bÄda Ären under hösten. Inga tecken pÄ varaktig habitatförlust upptÀcktes dÄ tumlarnÀrvaron Äterigen ökade efter avslutat fiske.One of the biggest threats for the harbour porpoise (Phocoena phocoena) population is the risk of bycatch in gillnet fisheries. Because of this acoustic pingers to be used on gillnets have been developed that minimize the bycatch of harbour porpoise. Since 2015 there have been six hydrophones (C-PODs) developed by Chelonia Limited placed around SkÀlderviken and Kullaberg for detection of porpoise activity. The same area has also been exposed for gillnet fishing. Two C-PODs were controls since they were assumed not to be affected by the fishing in the area. The fishing was divided into high and low fishing pressure depending on the length of the fishing nets and how long they were placed in the water. Collected data between 2015 and 2016 were compiled in a database where the variable DPM/hour (Detective Positive Minutes) indicated if a porpoise had been close by. The aim of the study was to determine if and how the variation of porpoise activity changed due to the fishery using pingers. Temporal and spatial variance between the different seasons and C-PODs could be confirmed for both years. There was also a difference in activity between C-PODs, regardless if the C-PODs where placed on the same side of the peninsula or not. The highest activity was reached at the tip of the Kullen peninsula, at both control C-PODs and during autumn. The lowest activity was at two C-PODS close to the fishing nets using pingers. The harbour porpoise presence was in general lower during the periods with fishing and would thereafter increase after the fishing had ended. No signs of enduring habitat loss were detected because of the increase in presence of harbour porpoise after the fishing was finished

    Get a Room! How Writing Groups Aid the Development of Junior Academics’ Writing Practice and Writer Identity

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    The present study revisits writing retreat participants who have spontaneously formed writing groups before or after attending a retreat hosted by the Unit for Academic Language at the University of Gothenburg, Sweden. All in all, 11 doctoral students and one postdoc were interviewed using a semi-structured interview model. The answers were thematically analysed based on Murray’s (2014) concept of coherence in writing groups as well as parts of Aitchison and Lee’s (2006) key characteristics of writing groups. The two main research questions posed concern (i) whether the informants have changed their writing practice and/or the way they think and feel about writing since joining a writing group, and (ii) whether possible changes have aided the development of their identity as academic writers. Results show that the informants have indeed changed central aspects of their writing practice and that this in turn has positively influenced how they now think and feel about writing. This has to some extent contributed to the informants’ development of their writer identity; however, the present study also sheds light on the fact that more needs to be done at departmental levels across the university to make academic writing visible

    Prisutvecklingen pÄ bostÀder i Malmö - En statistisk jÀmförelse med Stockholm och Göteborg

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    BostĂ€der bestĂ„r antingen av hela fastigheter eller av delar av fastigheter. Fastigheter och deras priser Ă€r intressanta i förhĂ„llande till andra varor dĂ„ de Ă€r knutna till en precis lokalisering. Priset pĂ„ en fastighet sĂ€ger mycket om vĂ€rdet av den lokalisering som fastigheten har. För en stad Ă€r prisutvecklingen en slags temperaturmĂ€tare och speglar en förĂ€ndring i attraktivitet för ett visst lĂ€ge. Syftet med examensarbetet Ă€r att förklara avvikelsen i prisutveckling pĂ„ bostĂ€der i Malmö. Fokus ligger primĂ€rt pĂ„ att undersöka syftet utifrĂ„n den grundlĂ€ggande nationalekonomi som speglar de mest sjĂ€lvklara teoretiska förklaringarna i form av en utbudseffekt eller efterfrĂ„geeffekt i Malmö jĂ€mfört med Stockholm och Göteborg. UtgĂ„ngspunkten Ă€r att marknaderna i Malmö, Göteborg och Stockholm fungerar pĂ„ samma sĂ€tt. I andra hand undersöks avvikelsen i prisutveckling utifrĂ„n perspektivet att marknaderna i Malmö, Stockholm och Göteborg fungerar pĂ„ principiellt olika sĂ€tt. Fokus ligger i det hĂ€r steget pĂ„ att undersöka om det finns en effekt frĂ„n Öresundsregionen, alternativt om bostadsmarknadens struktur i Malmö har en effekt pĂ„ prisutvecklingen i förhĂ„llande till Stockholm och Göteborg. Valda metoder för att utföra undersökningen har formats med hĂ€nsyn till det statistiska materialet som funnits tillgĂ€nglig med utgĂ„ngspunkt i den utvalda litteraturen. En allmĂ€n litteraturstudie har gjorts för att fĂ„ bakgrund till vad som pĂ„verkar ett pris. HĂ€r görs djupdykning i relevanta ekonomiska teorier om utbud och efterfrĂ„gan samt tillĂ€mpningar pĂ„ fastighets- och bostadsmarknaden. För att styrka eller förkasta de teoretiska och praktiska antagandena undersöks den insamlade statistiken kvantitativt. Det insamlade datamaterialet testas sedan genom en regressionsanalys. Analysen genomförs genom tvĂ„ modeller, en modell som jĂ€mför Malmö med Stockholm samt en modell som jĂ€mför Malmö med Göteborg. Slutligen genomförs en samlad analys och slutsatser dras. Det kan konstateras att Malmö jĂ€mfört med Stockholm och Göteborg har en avvikande befolkningstillvĂ€xt som samvarierar med prisutvecklingen pĂ„ bostĂ€der. Övriga variabler som tagits fram samvarierar varken med prisutvecklingen eller befolkningstillvĂ€xten. Den avvikande prisutvecklingen pĂ„ bostĂ€der i Malmö beror inte pĂ„ varken en utbudseffekt eller efterfrĂ„geeffekt. Det leder till ett förkastande av antagandet om att marknaderna i Malmö, Stockholm och Göteborg skulle fungera pĂ„ fundamentalt lika sĂ€tt. Det kan ocksĂ„ konstateras att den avvikande prisutvecklingen pĂ„ bostĂ€der i Malmö inte beror pĂ„ en effekt frĂ„n regionen. Det finns dock förklaringskraft i en vĂ€lfungerande och stabil hyresmarknad i Malmö, möjligtvis med grund i det systematiska hyressĂ€ttningssystemet med lĂ€gesbaserade parametrar. Det leder till ett styrkande av antagandet om att bostadsmarknaden i Malmö jĂ€mfört med bostadsmarknaderna i Stockholm och Göteborg fungera pĂ„ principiellt olika sĂ€tt.Real estate and its prices are interesting in relation to other goods due to the strong linkage to a precise location. The price of a property says a lot about the value of its location. For a city, price development is a strong indicator and reflects a change in attractiveness for a particular location. The purpose of this Master Thesis is to explain the deviation in price development on dwellings in Malmö. The focus is primarily to investigate the purpose based on basic national economy to study the most obvious theoretical explanations in terms of effects due to supply or demand in Malmö compared to Stockholm and Gothenburg. The assumption that the housing markets in Malmö, Gothenburg and Stockholm operate in the same way is in this perspective fundamental. Secondly, the deviation in price development is studied from the perspective that the housing markets in Malmö, Gothenburg and Stockholm operate in fundamentally different ways. Focus is to investigate whether there is an effect from the Öresund region, or whether the structure of the housing market in Malmö has an effect on price developments in relation to Stockholm and Gothenburg. The selected methods chosen for carrying out the study are colored by the available statistical material and on the selected literature. Relevant economic theories about supply and demand are investigated as well as applications on the property and housing market. In order to strengthen or reject the theoretical and practical assumptions, the collected statistic material examines quantitatively. The collected data is tested by a regression analysis. To perform the analysis two models are constructed; a model that compares Malmö and Stockholm as well as a model that compares Malmö and Gothenburg. The comprehensive analysis leads to the results and conclusions are finally drawn. The thesis distinguishes that Malmö compared to Stockholm and Gothenburg has a deviating population growth that coincides with deviation in price development on dwellings. Other variables created do not coincide with either the price development or population growth. The divergent price development on dwellings in Malmö cannot be explained by either an effect due to supply or demand. This fact leads to a rejection of the assumption that the housing markets in Malmö, Gothenburg and Stockholm would fundamentally operate in the same way. The thesis also distinguishes that the divergent price development on dwellings in Malmö cannot be explained by an effect from the Öresund region. However, the thesis finds an explanation in the well-functioning and stable rental market in Malmö, possibly due to the systematic rental system with location-based parameters. This leads to a strengthening of the assumption that the housing market in Malmö compared to the markets in Stockholm and Gothenburg operates in fundamentally different ways

    Risk factors for marginal ulcer after gastric bypass surgery for obesity:A population-based cohort study

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    ObjectiveThis study aimed to assess risk factors for developing marginal ulcer (MU) after gastric bypass (GBP) surgery for obesity.BackgroundMU is a common and potentially serious complication of GBP surgery, little is known about its etiology.MethodsThis population-based cohort study of GBP in 2006-2011 evaluated MU in relation to diabetes, hyperlipidemia, hypertension, chronic obstructive pulmonary disease (COPD), ulcer history, use of proton pump inhibitors (PPIs), aspirin, nonsteroidal anti-inflammatory drugs (NSAIDs), and selective serotonin reuptake inhibitors (SSRIs). Multivariable Cox proportional hazard regression models estimated hazard ratios (HRs) and 95% confidence intervals (CIs), adjusted for confounding.ResultsAmong 20,294 GBP patients, diabetes and peptic ulcer history entailed statistically significantly increased risk of MU (HR = 1.26, 95% CI 1.03-1.55 and HR  =  2.70, 95% CI 1.81-4.03), although hyperlipidemia, hypertension, and COPD did not. PPI users had an increased HR of MU (HR  =  1.37, 95% CI 1.17-1.60). Aspirin and NSAID consumption less than or equal to median entailed decreased HRs of MU (HR  =  0.56, 95% CI 0.37-0.86 and HR  =  0.30, 95% CI 0.24-0.38), although aspirin and NSAID users more than median had an increased risk and no association with MU, respectively (HR  =  1.90, 95% CI 1.41-2.58 and HR  =  0.90, 95% CI 0.76-1.87). The use of SSRI less than or equal to median had a decreased risk of MU (HR  =  0.50, 95% CI 0.37-0.67), although use more than median entailed increased HR (HR  =  1.26, 95% CI 1.01-1.56).ConclusionsDiabetes and peptic ulcer history seem to be risk factors for MU, but not hyperlipidemia, hypertension, or COPD. Limited doses of aspirin, NSAIDs, and SSRIs might not increase the risk, although higher doses of aspirin do. The association with PPI could be due to confounding by indication

    GANDER: a Platform for Exploration of Gaze-driven Assistance in Code Review

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    Gaze-control and gaze-assistance in software development tools have so far been explored in the setting of code editing, but other developer activities like code review could also benefit from this kind of tool support.In this paper, we present GANDER, a platform for user studies on gaze-assisted code review. As a proof of concept, we extend the platform with an assistant that highlights name relationships in the code under review based on gaze behavior, and we perform a user study with 7 participants. While the participants experience the interaction as overwhelming and lacking explicit actions (seen in other similar user studies), the study demonstrates the platform's capability for mobility, real-time gaze interaction, data logging, replay and analysis

    Eligibility rates and representativeness of the General Medical Services scheme population in Ireland 2017-2021: A methodological report [version 1; peer review: 2 approved]

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    Background: In Ireland, the means tested General Medical Services (GMS) scheme provides access to a range of healthcare services at no or low cost to approximately one third of the population. Individuals eligible for the GMS scheme are often a focus of research, as a population that account for a large proportion of healthcare services use. The aim of this study is to describe the eligibility rates and representativeness of the GMS scheme population over time, with respect to age group, sex, and geographical area in Ireland. Methods: Population data was obtained from the Central Statistics Office (CSO), using 2016 Census figures and projected population figures for 2017-2021. GMS eligibility figures for 2016-2021 were obtained from the HSE Primary Care Reimbursement Service (PCRS). GMS eligibility rates and relative rates of eligibility were calculated for 2016-2021 by age group and sex. Additionally, 2016 eligibility rates were calculated by geographical area. Results: The crude eligibility rate decreased from 36.4% in 2016 to 31.2% in 2020, with a slight increase to 31.6% in 2021. In the 75+ years age group, 78.2% of the total population were eligible for the GMS scheme in 2021. The age group with the lowest rate of eligible individuals was the 25-34 age group, with 19.5% eligible in 2021. The eligibility rate was higher among females compared to males throughout the study period. The highest eligibility rate was seen in Donegal, with a crude rate of 52.8%. Dublin had the lowest rate, with a crude rate of 29.3%. Conclusions: GMS eligibility varies greatly depending on age, sex, and geographical area, and decreased between 2016 and 2021. This study uses the most up-to-date data available to provide age group, sex and area-based figures for GMS eligibility which may inform planning and conduct of research focusing on GMS-eligible individuals

    Vall och helsÀd ger mycket biogas!

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    I ett samarbete mellan Sveriges lantbruksuniversitet (SLU) och Lunds universitet har en forskargrupp undersökt hur snittlĂ€ngden vid hackning av vall och helsĂ€d, som biogasgrödor, pĂ„verkar metanpotentialen, energiavkastning och produktionskostnad. Resultaten visar pĂ„ ett högt energiutbyte bĂ„de hos vall och helsĂ€d. Vidare Ă€r sambandet mellan snittlĂ€ngd och metanpotential mer komplext Ă€n förvĂ€ntat. Det verkar inte alltid vara lönt att hacka fint – tvĂ€rtom ser det i vissa fall ut till att bĂ„de leda till minskat energiutbyte och kosta mer. Den viktigaste slutsatsen Ă€r att optimera metanpotential hos biogasrĂ„varan först genom att vĂ€lja rĂ€tt skördetidpunkt. Resultaten visar att det Ă€r möjligt att spara diesel och arbetstid genom att vĂ€lja en lĂ€ngre snittlĂ€ngd

    Vall och helsÀd som biogassubstrat

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    Vall samt rĂ„g och vete skördad som helsĂ€d anvĂ€nds idag som biogasrĂ„vara i Sverige. Tidigare studier har visat att metanpotentialen, energiutbytet och Ă€ven substratkostnaderna skiljer sig beroende pĂ„ nĂ€r grödorna skördas samt hur fint materialet hackas. MĂ„let med detta projekt var dĂ€rför att undersöka hur vall och helsĂ€d effektivare kan utnyttjas som biogassubstrat genom att optimera skördetidpunkt och snittlĂ€ngd. Andra forskningsfrĂ„gor var hur biomassaavkastning i fĂ€lt samt snittlĂ€ngdsinstĂ€llningar hos exakthacken pĂ„verkar dieselförbrukning och skördeÂŹkapacitet vid skörd av vall och helsĂ€d. Med hjĂ€lp av dynamiska skörde- och transportlogistikmodeller som, baserat pĂ„ uppgifter om dieselförbrukning och tidsĂ„tgĂ„ng frĂ„n ett skördeexperiment, gav dieselförbrukning och skördeÂŹkapacitet vid olika snittlĂ€ngdsinstĂ€llningar, skördetidpunkter och val av grödor. Resultaten visade att nĂ€r snittlĂ€ngden ökade frĂ„n 3,5 till 9 mm, minskade diesel- och tids-Ă„tgĂ„ngen med 17 respektive 33 %. SnittlĂ€ngdstĂ€llningar pĂ„verkar Ă€ven metanpotentialen som bestĂ€mdes i labbtest. Sambandet Ă€r dock mer komplext Ă€n tidigare vĂ€ntat. I vĂ„ra studier har det visat sig att det inte alltid Ă€r lönt att hacka fint – tvĂ€rtom kan det bĂ„de leda till minskat energiutbyte och kosta mer. För vall och vete ledde en finare hackning (4 istĂ€llet för 12 mm) till att metanpotentialen minskade med 9 respektive 13 %, medan den ökade med 12 % nĂ€r rĂ„g hackades finare. Det behövs fler detaljstudier som undersöker mekanismerna bakom de resultat som presenterats hĂ€r samt sĂ€tter det i samband med skördetidpunkten, t.ex. med grödans mognadsgrad och TS-halt som faktorer. Potentiella energivinster och substratkostnader berĂ€knades med hjĂ€lp av livscykelmetodologi. Energivinsten för rĂ„g och vete var mycket hög, 36 respektive 33 MWh/ha. Detta motsvarar en energiuppvĂ€xling pĂ„ drygt 5 gĂ„nger den insatta energin. Energivinsten frĂ„n vall blev 24 % lĂ€gre Ă€n för rĂ„g, 28 MWh/ha. Detta baserades pĂ„ de skördenivĂ„er för vall, rĂ„g och vete pĂ„ 12,2, 12,1 och 12,1 ton torrsubstans per hektar och Ă„r, vilka mĂ€ttes i fĂ€ltexperiment. Siffrorna har justerats för förluster vid skörd, transport och lagring, som ocksĂ„ mĂ€ttes i projektet. Energivinsten för rĂ„g och vete kan vara Ă€nnu större, eftersom andra studier, som gjorts i samarbete mellan SB3 och SLU Alnarp, har visat att skördeökningar pĂ„ 25-30 % Ă€r möjliga. DĂ€remot förvĂ€ntas biomassaavkastningen av vall inte utvecklas pĂ„ samma sĂ€tt, tvĂ€rtom, sĂ„ visar tidigare studier att andra Ă„rets skördar av vall kan vara upp till 30 % lĂ€gre Ă€n första Ă„rets. De undersökta biogassubstraten hade lĂ€gre kostnader Ă€n betalningsförmĂ„gan frĂ„n en potentiell biogasanlĂ€ggning. Under de bĂ€sta förutsĂ€ttningarna hade rĂ„g och vete de lĂ€gsta total-kostnaderna (514 respektive 521 kr/MWh) för produktion av fordonsgas. Fordonsgas frĂ„n vall i 3-skördesystem hamnade ca 10 % högre, pĂ„ 570 kr/MWh. Vallens funktion som avbrottsgröda och dess goda egenskaper vad gĂ€ller markkolsuppbyggnad bidrar med att koldioxid binds i marken samtidigt som markens bördighet höjs potentiellt. Dessutom kommer fordonsbrĂ€nsle producerad av vall förmodligen att rĂ€knas som andra generationens avancerade biobrĂ€nslen, som Ă€r berĂ€ttigat till skattereduktion, samt vars produktion, enligt EU-regler under förhandling 2015, fĂ„r rĂ€knas dubbelt i den nationella statistiken för produktion av förnybar energi

    Individualization of Hematopoietic Stem Cell Transplantation Using Alpha/Beta T-Cell Depletion

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    Allogeneic hematopoietic stem cell transplantation (HSCT) is associated with several potentially lethal complications. Higher levels of CD3+ T-cells in the graft have been associated with increased risk of graft-versus-host disease (GVHD), but also beneficial graft-versus-leukemia effect and reduced infections. To tackle post-transplant complications, donor lymphocyte infusions have been used but with an increased risk of GVHD. To reduce this risk, we performed depletion of αÎČ T-cells and treated 12 patients post-HSCT suffering from infections and/or poor immune reconstitution. The αÎČ T-cell depleted cell products were characterized by flow cytometry. The median log depletion of αÎČ T-cells was −4.3 and the median yield of γΎ T-cells was 73.5%. The median CD34+ cell dose was 4.4 × 106/kg. All 12 patients were alive 3 months after infusion and after 1 year, two patients had died. No infusion-related side effects were reported and no severe acute GVHD (grade III-IV) developed in any patient post-infusion. Overall, 3 months after infusion 11 out of 12 patients had increased levels of platelets and/or granulocytes. In conclusion, we describe the use of αÎČ T-cell depleted products as stem cell boosters with encouraging results
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