372 research outputs found
La corea en la infancia : Tesis presentada para optar al grado de doctor en medicina
No full textFil: Castro y Sundblad, Carlos. Universidad de Buenos Aires. Facultad de Medicina. Buenos Aires, Argentina.La observación de once casos de corea tratados con buen éxito por el hidrato de cloral y bromuro de potasio, a dosis progresivas, han inducido a Carlos Castro y Sundblad a estudiar esta enfermedad, como lo hace en cinco capítulos destinados a la etiología, síntomas, diagnóstico, pronóstico y tratamiento.A la cabeza de portada: Facultad de Ciencias Médicas. - Incluye nómina de Catedráticos y Asignaturas. Tesis con dedicatorias. 55 p. ; 23 cm
Effects of physical activity and gravitational stress on cardiovascular control
No full textThe long-term goal of the present work was to characterize the responses to gravitational challenges in exercising humans after long-term head-down-tilt bedrest (HDT). HDT is a simulation of weightlessness with respect to effects on the systemic circulation, and previous studies in resting men have suggested that impairments of arterial baroreflexes contribute to the orthostatic intolerance seen after HDT and spaceflight. However, orthostatic challenges are commonly associated with physical activity, so a characterization of cardiovascular responses to gravitational challenges during exercise rather than rest was considered to provide more physiologically relevant information. Furthermore, it was hypothezised that cardiovascular impairments, if any, would be caused by hemodynamic rather than baroreflex mechanisms.In a first step, we studied the applicability during exercise of methods developed for studies of baroreflexes in resting humans. Such methods include apnea during short-lasting carotid sinus stimulation, and they assume a fixed temporal coupling between carotid stimulus and cardiac response. In the present exercise experiments it was found that apnea induced marked bradycardia and hypertension that tended to confound all but the first 5 s of the response to a carotid stimulation initiated 4-5 s after the onset of apnea. Also, both orthostatic stress and exercise were associated with a variable latency of the carotid-cardiac baroreflex. In keeping with these findings an alternative mode of baroreflex stimulation, including rapid tilting during eupnea, was developed for exercise studies.In a second step, the cardiovascular responses to rapid tilting were studied in healthy exercising men. The tilts induced a complex pattern of arterial pressure (AP) fluctuations: The efficiency of the skeletal muscle pump promptly changed with posture and with an equally prompt effect on the (virtual) total peripheral conductance. There are also changes in AP at heart level were induced because the heart is located cranial from the hydrostatic indifferent point. In addition, during tilt from upright to supine there were indications that left ventricular stroke volume (SV) transiently decreased due to a rapid increase in right ventricular preload, which acted to impede left ventricular filling (direct ventricular interdependence). The baroreflex control of heart rate (HR) was analyzed with a dynamic model in which HR was a basically linear function of AP recorded at a site between the heart and the carotid sinus. Non-linearities of the FIR responses could be modelled as a result of varying fractional contributions of fast vagal and slow sympathetic HR responses.In a third step, baroreflex and hemodynamic responses were studied in exercising men before and after six weeks of strict HDT. HDT did not alter arterial-cardiac baroreflex sensitivity during light exercise, which is in contrast to previous findings obtained during supine resting conditions. The indices of direct ventricular interdependence were abolished immediately after long-term bedrest; it is suggested that an initial hypovolemia brought about smaller exercise heart volumes, and that the restrictive action of the pericardium was decreased. Within two days, when the plasma volume had been restored, the signs of ventricular interdependence returned to control values. The cardiovascular responses to exercise after long-term strict bedrest differed from those seen after bed rest of shorter duration and after space flights that included exercise countermeasures. Thus, in the present study there were prominent decreases of SV in both supine and upright exercise (-25±3% and -30±5%, respectively). The decrease in SV during submaximal exercise persisted even after the bed-rest-induced plasma hypovolemia had normalized. There was a more complete recovery of SV and cardiac output during upright exercise compared to exercise in the supine position, where SV had not recovered fully after one month. This suggests a stiffer, and probably smaller, heart that was unable to increase SV with the increased preload induced by supine exercise. It is concluded that cardiovascular impairments in exercising men after long-term bedrest are of hemodynamic rather than of baroreflex origin.List of scientific papersI. Sundblad P, Linnarsson D (1996). Influence of apnea on cardiovascular responses to neck suction during exercise. Am J Physiol. 271(4 Pt 2): H1370-374. https://pubmed.ncbi.nlm.nih.gov/97053418II. Sundblad P, Linnarsson D (1996). Slowing of carotid-cardiac baroreflex with standing and with isometric and dynamic muscle activity. Am J Physiol. 271(4 Pt 2): H1363-H1369. https://pubmed.ncbi.nlm.nih.gov/97053417III. Sundblad p, Haruna Y, Tedner B, Linnarsson D (1999). Short-term cardiovascular responses to rapid whole body tilting during exercise. Eur J Appl Physiol. [Accepted]IV. Sundblad P, Spaak J, Linnarsson D (1999). Hemodynamic and baroreflex responses to whole body tilting in exercising men before and after six weeks head-down bedrest. [Submitted]V. Sundblad P, Spaak J, Linnarsson D (1999). Cardiovascular responses to upright and supine exercise after six weeks head-down bedrest. [Submitted]</p
Perceived health in Swedish school students : a longitudinal prevalence study
No full textThis thesis, with a national sample of Swedish school students, is part of a collaborate project between Karolinska Institutet, The Swedish School of Sport and Health Sciences and Stockholm Institute of Education carried out in 2001 and with a follow-up study in 2004.The overall aim of the collaboration was to investigate the conditions and circumstances surrounding school children's physical activities, their physical capacity, and general health status, with special attention paid to changes over time and with increase in age. The main aim of this thesis was to study students' perceived health, pain and reported injuries sustained during physical activity, with a focus on gender and age/grade differences (Study I and II). The aim of the third study was to examine changes in perceived health with increasing age within the same individual as well as over time at grade level e.g. comparing the cohort of same school-grade with a three-year interval. In addition, the aim was to investigate if factors, such as gender, age (grade level), stress, and level of physical activity were related to perceived health (Study III). The aim of the fourth study was to compare agreement of answers, given by the students with those given by their parents, to questions addressing students' medical background, injuries and perceived health.An independent random selection of Swedish schools (n=48) enrolling grades 3, 6 and 9 was performed. In 2001, a total of 1,908 students participated in Studies I and II. The subjects in Study III were those school-students (n=1,276) who participated in the base study (2001) and who subsequently answered a mailed-out questionnaire in 2004. The subjects in Study IV were recruited from eleven different schools and were a sub-sample of schools that participated in the base study. The students attended grade 6 during the base study and were at the time of the investigation attending grade 8. Their parents were, at the same time, contacted and 186 corresponding student-same parent answers were collected.A special health and injury questionnaire was constructed for the purpose of the studies. Every sixth student (n=299 or 16 %) reported m injury during the recall period (Study I). The most common type of injury was a sprain, sustained through a fall or a twisting movement. The lower extremity was the most frequently injured body site. There was a gender difference in injuries reported during physical education class, an age difference during organized sports but no age or gender differences during leisure activities. Every other student (50 %) reported that they previously had injured the same body part.Fifty percent of the students reported that they had experienced pain, either as headache, abdominal pain or musculoskeletal pain, within the recall period (Study II). Gender differences were especially noticeable for headaches. Cooccurrence among the variables was moderate. For the total of the seven variables, the perception of pain and health complaints decreased with age for boys from grade 3 to 9, while multiple complaints increased for girls.Results from the follow-up study (2004) showed for girls a continuing increase of frequent complaints over the three year period (Study III). In contrast, boys reported a decrease with the exception of tiredness, which increased with age for both genders. More girls (12 %) than boys (4 %) reported frequent pain at both measurement periods. When comparing change in assessment at grade level most variables were rated the same as three years earlier. Prevalence as well as change in prevalence of frequent complaints of pain and perceived health were related to gender and increasing age.Stress as an explanatory factor for pain and health complaints was especially significant for girls and the risk of complaints, was most evident for students who were characterized as being physically inactive in 2001 and remained inactive three years later. Once a child is in good health, in absence of disease, pain and injury, his or her assessment matches up with their parent (Study IV). Children and parents also showed agreement in cases of severe injuries and daily complaints of knee pain. Less frequent headaches, back- and musculoskeletal pain and other complaints of minor injuries and tiredness, were all underreported and under-rated by their parents. This suggests that when assessing the perceived health and well-being of students, their own expressions should be the basis for the data collection and analysis rather than relying entirely on parental reports.List of scientific papersI. Sundblad G, Saartok T, Engstrom LM, Renstrom P (2005). Injuries during physical activity in school children. Scand J Med Sci Sports. 15(5): 313-23. https://pubmed.ncbi.nlm.nih.gov/16181255 II. Sundblad GM, Saartok T, Engstrom LM (2006). Prevalence and co-occurrence of self-rated pain and perceived health in school-children: Age and gender differences. Eur J Pain. [Accepted] https://pubmed.ncbi.nlm.nih.gov/16542860 III. Gunilla Brun Sundblad, Anna Jansson, Tönu Saartok, Per Renström, Lars-Magnus Engström (2006). Self-rated pain and perceived health in relation to stress and physical activity among school-students; A 3-year follow-up. [Submitted]IV. Gunilla Brun Sundblad, Tönu Saartok, Lars-Magnus Engström (2006). A valid question and a reliable answer, A child-parent agreement study. [Submitted]</p
Influence of posture on left ventricular long- and short-axis shortening
No full textEnd-diastolic volume and left ventricular stroke volume are increased in the supine compared with upright position, but the contribution of long-axis (LAS) and short-axis shortening (SAS) to these changes with change in posture has not been established. We examined long- and short-axis motion and dimensions with echocardiography in 10 healthy subjects in the upright and supine position. Long-axis length at end diastole was almost identical, whereas the diastolic short-axis diameter was increased in the supine position. At end systole, there was a decreased long-axis length and increased short-axis length in the supine vs. upright position. Both LAS and SAS were enhanced in supine vs. upright positions [LAS: 9.3 +/- 2.2 vs. 15.1 +/- 3.1 mm (P < 0.001); SAS: 12.7 +/- 3.2 vs. 16.3 +/- 2.8 mm (P < 0.001)], presumably via Starling mechanisms. LAS increased more in the lateral part of the mitral annulus than in the septal part [7.7 +/- 2.6 vs. 4.0 +/- 2.8 mm (P < 0.006)], which implies that the more spherical form, in the supine position, induces more stretch at the lateral free wall than in the ventricular septum. These findings support the notion that Starling mechanisms affect systolic LAS.</p
Laborera meraKan laborativt arbetssätt under de tidiga skolåren förebygga matematiksvårigheter?
No full textPersson, K., Rooth, P., Sundblad, S. och Uthas, K. (20008). Laborera mera – Kan ett laborativt arbetssätt i de tidiga skolåren förebygga matematiksvårigheter? (Explore more – Can difficulties in mathematics be prevented with laboratory work in the early school years?) Högskolan, Kristianstad. Specialpedagogiska programmet. Syftet med följande arbete är att undersöka om ett laborativt arbetssätt under de tidiga skolåren förebygger matematiksvårigheter. Vi undersöker och jämför därför arbetssättet i matematik i en Montessoriskola, i en Waldorfskola och en skola där man medvetet betonar laborativa inslag i matematikundervisningen. Som jämförelse undersöker vi också matematikundervisningen i en skola med traditionell undervisning. Arbetet ger en översikt av tidigare forskning om matematikförståelse, räknefärdigheter, konkretiserande arbetssätt och laborativt material. Vidare ger det en översikt över lärarens aktiva roll, elevers lärande, de olika pedagogiska metoder och arbetssätt som vi valt att inrikta oss på samt specialpedagogens roll. I litteraturgenomgången tar vi även upp de teorier vi använder oss av. Med hjälp av intervjuer, observationer och test vill vi få svar på i vilken omfattning laborativa hjälpmedel förekommer i matematik i år 2, om elever i år 5 som arbetar laborativt under de tidiga skolåren har en bättre förmåga att lösa matematiska problem i nationella ämnesproven i matematik, om någon av de pedagogiska metoderna är en bättre metod för att utveckla matematisk problemlösningsförmåga samt vilka arbetssätt vi som specialpedagoger kan implementera för att stärka den matematiska förmågan hos eleverna. Sammanfattningsvis pekar resultaten på att laborativt arbetssätt är ett viktigt redskap för lärare när matematiken ska tydliggöras. Vi menar även att studien visar att det krävs en tydlig lärarroll, där undervisningen medvetet styrs och att uppgifterna i matematik bör finnas på olika nivåer inom samma moment, så att eleverna kan arbeta i sin närmaste utvecklingszon
UTOPIA: Participatory Design from Scandinavia to the World
No full textStudies and design of Information Technology support for workplaces, especially workshop floors, office floors and hospital floors, have a strong tradition in Scandinavia, involving workplace users and their trade unions and other stakeholders. The projects emphasize the active co-operation between researchers and workers in the organizations to help improve their work situation. This tradition is here put into and analysed in its historic perspective, starting with the roots in Norway in the early 1970s and highlighting the seminal UTOPIA project from the early 1980s. Today computer use and interaction possibilities are changing quickly, with use contexts and application types radically broadening. Technology no longer consists of static tools belonging only to the workplace, but permeates work on the move, homes and everyday lives. The Scandinavian tradition of user involvement in development is facing up with the challenges of new contexts. The influence on past and current practices for ICT system design internationally in described and analysed.</p
Efficiency of a constructed wetland for retention of sediment associated phosphorus
No full textA constructed wetland (2.1 ha; 2% of catchment area) in southeast Sweden, in a catchment with 35% arable land on clay soils, was investigated with respect to phosphorus (P) retention, focusing on particulate P (PP) and sediment accretion. The aims were to i) estimate P retention and identify the dominating retention processes; ii) investigate how well estimates of P retention based on inflow-outflow measurements compared with the amount of P accumulated in the sediment. In- and outflow of P was measured during four years with continuous flow measurements and flow proportional weekly composite samples. P in the accumulated sediment was estimated based on core samples and analyzed using sequential fractionation. Total P load during four years was 65 kg/ha and intensive sampling events detected 69% as PP. Based on inflow-outflow estimates the mean P retention was 2.8 kg/ha/yr, or 17%, but the amount of P accumulated in the inlet zone equated 78% of the TP load. This discrepancy showed the need to add studies of sediment accumulation to inflow-outflow estimates for an improved understanding of the P retention. The dominating P forms in the sediment were organic P (38%) and P associated with iron or aluminum (39%), i.e. potentially mobile forms. In areas colonized by Typha latifolia, the amount of P in the upper sediment layer (390 kg) was more than double the total P load of 136 kg. Cycling and release in those areas is a potential source of P that deserves further attention.The original publication is available at www.springerlink.com:Karin Johannesson, Jonas Andersson and Karin Sundblad-Tonderski, Efficiency of a constructed wetland for retention of sediment associated phosphorus, 2011, Hydrobiologia, (674), 1, 179-190.http://dx.doi.org/10.1007/s10750-011-0728-yCopyright: Springer Science Business Mediahttp://www.springerlink.com
Improvements in Maximal Oxygen Uptake after Sprint-Interval Training Coincide with Increases in Central Hemodynamic Factors
No full textIntroduction: Sprint-interval training has been shown to improve maximal oxygen uptake, in part through peripheral muscle adaptations that increase oxygen utilization. In contrast, the adaptations of central hemodynamic factors in this context remain unexplored. Purpose: The aim of the current study was to explore the effects of sprint-interval training on maximal oxygen uptake and central hemodynamic factors. Methods: Healthy men and women (n = 29, mean age 27 ± 5, height 175 ± 8 cm, body mass 72.5 ± 12.0 kg) performed 6 weeks of sprint-interval training consisting of 3 weekly sessions of 10-min low-intensity cycling interspersed with 3 x 30-s all-out sprints. Maximal oxygen uptake, total blood volume, and maximal cardiac output were measured before and after the intervention. Results: Maximal oxygen uptake increased by 10.3% (p < 0.001). Simultaneously, plasma volume, blood volume, total hemoglobin mass, and cardiac output increased by 8.1% (276 ± 234 mL; p < 0.001), 6.8% (382 ± 325 mL; p < 0.001), 5.7% (42 ± 41 g; p < 0.001), and 8.5% (1.0 ± 0.9 L · min-1; p < 0.001), respectively. Increased total hemoglobin mass along with measures of body surface area had significant impact on the improvements in maximal oxygen uptake. Conclusions: Six weeks of sprint-interval training results in significant increases in hemoglobin mass, blood volume, and cardiac output. As these changes were associated with marked improvements in maximal oxygen uptake, we conclude that central hemodynamic adaptations contribute to the improvement in maximal oxygen uptake during sprint-interval training
Extracellular cadmium in the bronchoalveolar space of long-term tobacco smokers with and without COPD and its association with inflammation
No full textBritt-Marie Sundblad,1,* Jie Ji,1,* Bettina Levänen,1 Klara Midander,2 Anneli Julander,2 Kjell Larsson,1 Lena Palmberg,1 Anders Lindén1 1Unit for Lung and Airway Research, 2Unit for Occupational and Environmental Dermatology, Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden *These authors contributed equally to this work Abstract: Tobacco contains cadmium, and this metal has been attributed a causative role in pulmonary emphysema among smokers, although extracellular cadmium has not to date been quantified in the bronchoalveolar space of tobacco smokers with or without COPD. We determined whether cadmium is enhanced in the bronchoalveolar space of long-term tobacco smokers with or without COPD in vivo, its association with inflammation, and its effect on chemokine release in macrophage-like cells in vitro. Bronchoalveolar lavage (BAL), sputum, and blood samples were collected from current, long-term smokers with and without COPD and from healthy nonsmokers. Cadmium concentrations were determined in cell-free BAL fluid using inductively coupled plasma mass spectrometry. Blood monocyte-derived macrophages were exposed to cadmium chloride in vitro. Depending upon the type of sample, molecular markers of inflammation were quantified either as protein (enzyme-linked immunosorbent assay) or as mRNA (real-time polymerase chain reaction). Cadmium concentrations were markedly increased in cell-free BAL fluid of smokers compared to that of nonsmokers (n=19–29; P<0.001), irrespective of COPD. In these smokers, the measured cadmium displayed positive correlations with macrophage TNF-α mRNA in BAL, neutrophil and CD8+ cell concentrations in blood, and finally with IL-6, IL-8, and MMP-9 protein in sputum (n=10–20; P<0.05). The cadmium chloride exposure caused a concentration-dependent increase in extracellular IL-8 protein in monocyte-derived macrophages in vitro. In conclusion, extracellular cadmium is enhanced in the bronchoalveolar space of long-term smokers and displays pro-inflammatory features. Its pathogenic role in tobacco-induced disease deserves further evaluation. Keywords: cigarette, metal, obstruction, macrophage, neutrophi
Designing assisted living technologies 'in the wild' : preliminary experiences with cultural probe methodology
No full textBackground
There is growing interest in assisted living technologies to support independence at home. Such technologies should ideally be designed ‘in the wild’ i.e. taking account of how real people live in real homes and communities. The ATHENE (Assistive Technologies for Healthy Living in Elders: Needs Assessment by Ethnography) project seeks to illuminate the living needs of older people and facilitate the co-production with older people of technologies and services. This paper describes the development of a cultural probe tool produced as part of the ATHENE project and how it was used to support home visit interviews with elders with a range of ethnic and social backgrounds, family circumstances, health conditions and assisted living needs.
Method
Thirty one people aged 60 to 98 were visited in their homes on three occasions. Following an initial interview, participants were given a set of cultural probe materials, including a digital camera and the ‘Home and Life Scrapbook’ to complete in their own time for one week. Activities within the Home and Life Scrapbook included maps (indicating their relationships to people, places and objects), lists (e.g. likes, dislikes, things they were concerned about, things they were comfortable with), wishes (things they wanted to change or improve), body outline (indicating symptoms or impairments), home plan (room layouts of their homes to indicate spaces and objects used) and a diary. After one week, the researcher and participant reviewed any digital photos taken and the content of the Home and Life Scrapbook as part of the home visit interview.
Findings
The cultural probe facilitated collection of visual, narrative and material data by older people, and appeared to generate high levels of engagement from some participants. However, others used the probe minimally or not at all for various reasons including limited literacy, physical problems (e.g. holding a pen), lack of time or energy, limited emotional or psychological resources, life events, and acute illness. Discussions between researchers and participants about the materials collected (and sometimes about what had prevented them completing the tasks) helped elicit further information relevant to assisted living technology design. The probe materials were particularly helpful when having conversations with non-English speaking participants through an interpreter.
Conclusions
Cultural probe methods can help build a rich picture of the lives and experiences of older people to facilitate the co-production of assisted living technologies. But their application may be constrained by the participant’s physical, mental and emotional capacity. They are most effective when used as a tool to facilitate communication and development of a deeper understanding of older people’s needs
- …
