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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
171

Evaluation of environmental samples as a sampling method for detecting pathogens in zebrafish

Lacorazza, Camila January 2019 (has links)
Zebrafish are becoming increasingly popular to use in different kinds of research projects as research animals, replacing rodents in many fields. When using animals for research, it is important to keep track of the animal health in order to get reliable results. The purpose of the study was to investigate whether these pathogens could be found analyzing environmental materials with real-time PCR instead of euthanizing fish and submitting them for histopathology. Also, to see if any material differentiated from the rest regarding accessibility to work with in a routine diagnostic laboratory.     This study was performed on environmental samples, such as filters, swabs, detritus and water, from a recirculating water system holding zebrafish. The pathogens analyzed were Mycobacterium chelonae, M. haemophilum, M. abscessus, M. marinum, M. fortuitum and Pseudoloma neurophilia, all common pathogens that can affect zebrafish.     All materials tested gave at least one positive result for most of the pathogens tested. Two pathogens were not detected, M. marinum and M. abscessus. Due to poorly working PCR-system for M. fortuitum, the results for that bacteria were deemed inconclusive. The filter materials and the swabs of the filter materials gave the best results in this small study, although all materials gave satisfactory results. In conclusion this study shows that environmental samples can be used to detect pathogens in zebrafish, but larger studies should be performed to better evaluate which material is the best one to use.
172

Retrospective serological and virological survey of influenza D virus among cattle in Sweden

Ahlgren, Evelina January 2019 (has links)
Respiratory diseases in cattle can cause economic losses due to the decreased dairy and meat production. Virus is the main reason for these diseases. Symptoms can be fever, cough and nasal discharge.     Influenza are a group of viruses belonged in the Ortomyxoviridae family. The big influenza groups are influenza A, B and C. The viruses can cause respiratory signs, and mammals can be affected. Recently a new influenza virus was found in the United States. The influenza virus was found in swine, but the natural host was later considered to be cattle. The virus was named influenza D. Different studies worldwide have confirmed the virus in a variety of regions. Antibodies have also been reported.     In this study, virologic and serologic methods were used to detect if influenza D circulates among cattle in Sweden. The serologic method performed was indirect ELISA. Serum and milk samples were investigated in the ELISA method. For the virologic detection a real-time RT-PCR was made, with a variety of study material.     Antibodies against influenza D were found in both serum and milk samples. No virus was found in the real-time RT-PCR. In Sweden the animal keeping is different compared to several other nations. For instance, the conditions of health and hygiene are better in Sweden, this may be an important cause of a system more resistant against spreading of infections. Influenza D could be more common in Sweden, but in that case further researches are needed to determine the prevalence.
173

Characterization of NeuN expression in the mouse neuronal NSC-34 cell line using RT-qPCR, immunological staining and siRNA-mediated gene suppression

Hallgren, Henrik January 2019 (has links)
Background: Acute spinal trauma is followed by a secondary injury that causes additional damage to the tissue. The mouse neuronal hybrid cell line NSC-34 is planned for studies regarding this process, wherefore the cell line needed to be established in the laboratory and a proof-of-concept study needed to be performed. A suitable target gene for this study was Neuronal Nucleus (NeuN), a neuronal marker expressed in nearly all neuronal cells although not yet studied in NSC-34. Aim: The aim of this project was to characterize the expression of NeuN in differentiated and undifferentiated NSC-34 cells and silence gene expression by using siRNA. Methods: RT-qPCR was used to measure NeuN expression during passages 5 to 15 and a comparison was performed between one early and one late passage. Lipofectamine® RNAiMAX was used for siRNA-treatment in different concentrations and several different medium compositions were tested as differentiation media. Results: NeuN was expressed in passages 5 to 15, with decreased expression levels in passage 13 (ΔCt 15.36 ± 0.16) compared to passage 5 (ΔCt 15.09 ± 0.16), p < 0.05. The expression levels did not change after differentiation. siRNA-treatment yielded knockdown when using  high concentrations of the reagent (p < 0.05). Conclusion: NeuN was expressed in a stable, low level throughout passages 5 to 15 with a slightly decreased expression during later passages and no change after differentiation. The siRNA-treatment suppressed gene expression, although further optimization is needed to increase the suppression.
174

Polyvinylalcohol-carbazate (PVAC) inhibits bacteria growth

Syk, Jakob January 2019 (has links)
Abstract Introduction This study evaluated the effect of the polymer polyvinylalcohol-carbazate (PVAC) on the bacteria Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis and Pseudomonas aeruginosa. PVAC is a polymer with a carbazate moiety that neutralizes free aldehydes and has shown great promise in stabilizing erythrocytes during long term storage. It has also been shown to reduce intraperitoneal adhesions after trauma. For this study, two Gram positive and two Gram negative bacteria strains were used with PVAC to evaluate its effect. Materials and methods PVAC was obtained from the research team at Ångström Laboratory, Uppsala. The bacteria were obtained from Clinical Microbiology and Hospital Hygiene, Academic Hospital, Uppsala. The methods used were spectrophotometric assessment of bacteria growth, use of FITC-conjugated PVAC to study adherence to bacteria, use of FITC-antibodies to study PVAC’s effect on bacterial adherence to erythrocytes and a qPCR for quantification of E. coli. Results and discussion PVAC displayed a clear effect of inhibition of bacteria growth in the study as shown by use of spectrophotometric assessment. Trials with FITC-PVAC showed that the polymer adheres directly to the bacteria, displaying a possible function of its inhibitory properties. The qPCR assay was able to detect the bacteria in all the dilutions used. Introduction This study evaluated the effect of the polymer polyvinylalcohol-carbazate (PVAC) on the bacteria Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis and Pseudomonas aeruginosa. PVAC is a polymer with a carbazate moiety that neutralizes free aldehydes and has shown great promise in stabilizing erythrocytes during long term storage. It has also been shown to reduce intraperitoneal adhesions after trauma. For this study, two Gram positive and two Gram negative bacteria strains were used with PVAC to evaluate its effect. Materials and methods PVAC was obtained from the research team at Ångström Laboratory, Uppsala. The bacteria were obtained from Clinical Microbiology and Hospital Hygiene, Academic Hospital, Uppsala. The methods used were spectrophotometric assessment of bacteria growth, use of FITC-conjugated PVAC to study adherence to bacteria, use of FITC-antibodies to study PVAC’s effect on bacterial adherence to erythrocytes and a qPCR for quantification of E. coli. Results and discussion PVAC displayed a clear effect of inhibition of bacteria growth in the study as shown by use of spectrophotometric assessment. Trials with FITC-PVAC showed that the polymer adheres directly to the bacteria, displaying a possible function of its inhibitory properties. The qPCR assay was able to detect the bacteria in all the dilutions used.
175

LEFT VENTRICULAR EJECTION FRACTION: A RETROSPECTIVE STUDY COMPARING 2D ECHOCARDIOGRAPHY AND GATED SINGLE PHOTON EMISSION COMPUTED TOMOGRAPHY (SPECT) IN CLINICAL USE.

Andersson, Jim January 2009 (has links)
<p><strong>Objectives</strong></p><p>The aim of this study was to compare left ventricular ejection fraction (LVEF) results derived from gated single photon emission computed tomography (SPECT) using Cedars-Sinai quantitative gated SPECT (QGS) processing software with results from 2D echocardiography, both obtained in routine clinical diagnostic use.</p><p> </p><p><strong>Methods</strong></p><p>Data from previously performed tests were obtained from 73 patients who had undergone both 2D echocardiography and gated SPECT within a time span of 6 months and had not had significant events that could influence LVEF. LVEF from 2D echocardiography was reassessed to obtain discrete values and then the data was compared using Bland-Altman analysis.</p><p> </p><p><strong>Results</strong></p><p>The correlation between the tests was shown to be good, but precision lacked. Bland-Altman analysis showed a bias of -0.8 percentage points when gated SPECT compared to mean values and 2 standard deviations (SD) ranged from -20.2 to 18.6.</p><p> </p><p><strong>Conclusions</strong></p><p>LVEF values from the two methods can differ quite a bit and comparisons between them should be done with great caution.</p> / <p><strong>Syfte</strong></p><p>Syftet med studien var att jämföra hur bra ultraljud av hjärta och isotopundersökning av hjärta stämmer överens när det gäller att visa hjärtats pumpförmåga.</p><p> </p><p><strong>Metod</strong></p><p>Data från tidigare utförda undersökningar av 73 patienter jämfördes. Patienter som hade gjort båda undersökningarna inom 6 månader och under perioden mellan undersökningarna inte hade haft hjärtinfarkt eller någon annan händelse som kan påverka hjärtats pumpförmåga valdes till studien.</p><p> </p><p><strong>Resultat</strong></p><p>Utslaget över hela studiepopulationen stämde resultaten från de båda undersökningarna bra överens. Jämförde man däremot resultaten från de båda undersökningarna med varandra patient för patient förekom mycket stora variationer.</p><p> </p><p><strong>Slutsats</strong></p><p>Resultaten angående hjärtats pumpförmåga kan skilja sig mycket från varandra. Jämförelser av värden från dessa två metoder bör därför göras med väldigt stor försiktighet.</p>
176

Dementia; common cause of suicide among elderly?

Andersson, Frida January 2006 (has links)
<p>Elderly committing suicide can be in a “preclinical phase” of dementia. Depressive symptoms may indicate a risk to develop a disease of dementia, for example Alzheimer’s Disease. Today almost 10% of the Swedish population older than 65 years suffer from a cognitive impairment diagnosed as dementia. Symptoms of dementia are associated with degenerative changes in the brain caused by a deposition of amyloid, leading among others things to a nerve cell death. A clinical diagnosis can be hard to set, and a definitive diagnose can only be set after a pathological examination, which only is possible after death. For this study we used Congo red staining of brains sections to find amyloid in autopsies from elderly people committing suicide. 35 cases (>60 year) were studied. Of the 35 cases 1/3 showed to be positive for amyloid deposition. This result in addition to other studies suggest that depressive symptoms is a “preclinical phase” of dementia, and therefore the suicide risk for this group must be consider to be elevated. However, more reliable prospective studies most be done to confirm this retrospective study.</p>
177

LEFT VENTRICULAR EJECTION FRACTION: A RETROSPECTIVE STUDY COMPARING 2D ECHOCARDIOGRAPHY AND GATED SINGLE PHOTON EMISSION COMPUTED TOMOGRAPHY (SPECT) IN CLINICAL USE.

Andersson, Jim January 2009 (has links)
Objectives The aim of this study was to compare left ventricular ejection fraction (LVEF) results derived from gated single photon emission computed tomography (SPECT) using Cedars-Sinai quantitative gated SPECT (QGS) processing software with results from 2D echocardiography, both obtained in routine clinical diagnostic use.   Methods Data from previously performed tests were obtained from 73 patients who had undergone both 2D echocardiography and gated SPECT within a time span of 6 months and had not had significant events that could influence LVEF. LVEF from 2D echocardiography was reassessed to obtain discrete values and then the data was compared using Bland-Altman analysis.   Results The correlation between the tests was shown to be good, but precision lacked. Bland-Altman analysis showed a bias of -0.8 percentage points when gated SPECT compared to mean values and 2 standard deviations (SD) ranged from -20.2 to 18.6.   Conclusions LVEF values from the two methods can differ quite a bit and comparisons between them should be done with great caution. / Syfte Syftet med studien var att jämföra hur bra ultraljud av hjärta och isotopundersökning av hjärta stämmer överens när det gäller att visa hjärtats pumpförmåga.   Metod Data från tidigare utförda undersökningar av 73 patienter jämfördes. Patienter som hade gjort båda undersökningarna inom 6 månader och under perioden mellan undersökningarna inte hade haft hjärtinfarkt eller någon annan händelse som kan påverka hjärtats pumpförmåga valdes till studien.   Resultat Utslaget över hela studiepopulationen stämde resultaten från de båda undersökningarna bra överens. Jämförde man däremot resultaten från de båda undersökningarna med varandra patient för patient förekom mycket stora variationer.   Slutsats Resultaten angående hjärtats pumpförmåga kan skilja sig mycket från varandra. Jämförelser av värden från dessa två metoder bör därför göras med väldigt stor försiktighet.
178

Dementia; common cause of suicide among elderly?

Andersson, Frida January 2006 (has links)
Elderly committing suicide can be in a “preclinical phase” of dementia. Depressive symptoms may indicate a risk to develop a disease of dementia, for example Alzheimer’s Disease. Today almost 10% of the Swedish population older than 65 years suffer from a cognitive impairment diagnosed as dementia. Symptoms of dementia are associated with degenerative changes in the brain caused by a deposition of amyloid, leading among others things to a nerve cell death. A clinical diagnosis can be hard to set, and a definitive diagnose can only be set after a pathological examination, which only is possible after death. For this study we used Congo red staining of brains sections to find amyloid in autopsies from elderly people committing suicide. 35 cases (&gt;60 year) were studied. Of the 35 cases 1/3 showed to be positive for amyloid deposition. This result in addition to other studies suggest that depressive symptoms is a “preclinical phase” of dementia, and therefore the suicide risk for this group must be consider to be elevated. However, more reliable prospective studies most be done to confirm this retrospective study.
179

Inhibiting the IGF-1 receptor with the cyclolignan Picropodophyllin: an in vitro study of ovulation, implantation and receptivity in a mouse model

Larsson, Patrik January 2008 (has links)
Picropodophyllin (PPP) is an analogue of the anti tumour lignan podophyllotoxin with the unique ability to selectively inhibit the receptor of Insulin like growth factor 1(IGF-1). IGF-1 is believed to play an important part in development of the endometrium facing implantation. With PPP treated mice, studies can be made to measure gene expression from tissue of both treated and untreated mice to compare the role of IGF-1 regarding ovulation, implantation and receptivity. The aim of this study was to analyze gene expression of some steroid hormone receptors and cytokines in ovaries from mice treated with PPP. In this study, seven mice were treated with PPP at different times and tissue was collected. PCR-primers for cDNA sequences of estrogene receptor α, estrogene receptor β, progesterone receptor A, progesterone receptor B, growth hormone receptor, interleukin 1 α, interleukin 1 β, tumour necrosis factor α and androgen receptor were used. Real Time PCR was run with the samples and gene expression was measured. The results of this study showed that the inhibition of IGF-1 receptor interacted with IGF-1 which lead to altered levels of estrogene receptor alpha, progesterone receptor, growth hormone receptor and androgen receptor that can decrease ovulation. The results also showed the differences in gene products between treated and untreated samples, suggesting that IGF-1 plays an important role regarding ovulation. / Studier med hjälp av den selektiva insulinlika tillväxtfaktor 1 receptorn (IGF-1R) antagonisten; picropodof?phyllin (PPP), hur samspelet mellan livmoderslemhinnan och implantationsprocessen, samt hur ovulationen påverkas av insulinlika tillväxtfaktorn 1 (IGF-1) kan nu utföras. IGF-1 tros ha en viktig roll för den reproduktiva processen, där den påverkar ovulation, implantation och embryoutveckling. IGF-familjen består av tre ligander; insulin, IGF-1 och IGF-2. IGF transporteras bundet till bindarprotein (IGFBP). Medlemmarna i IGF receptorfamiljen kan binda IGF-1, IGF-2 och insulin fast med olika affinitet. PPP som är en cykloligan, är en analog från podofyllotoxin och fungerar som en syntetisk IGF-1 receptorantagonist, som selektivt inhiberar receptorns aktivitet. PPP tros även kunna nedreglera genexpression av receptorn. Tre tidigare projektarbeten har utförts på vävnader från möss injicerade med PPP. Tyngdpunkterna i dessa arbeten har legat på immunhistokemiska studier av IGF-1 i reproduktionsorgan från möss, uttryck av IGF-1, dess receptor och bindarprotein 1 i ovarier och uterus efter behandling med PPP. I denna studie användes vävnad samt cDNA från sju möss behandlade med PPP, i olika stadier av reproduktionen samt även icke behandlade möss. Studiens syfte var att med sanntids-PCR jämföra genuttryck från östrogenreceptor α och β, progesteronreceptor A och B, tillväxthormonreceptor, Interleukin 1 α och β, ’tumor necrosis’ faktor α samt androgenreceptor i vävnad från PPP-behandlade och obehandlade möss och genom de erhållna resultaten från ovarievävnaden utläsa effekten på ovulationen och från uterusvävnaden effekten på implantation och receptivitet. Studieresultaten visade att IGF-1s frånvaro gav förändrade nivåer av genprodukter, som medförde minskad ovulationen. Studien visade att IGF-1s roll vid ovulationen var väsentlig.
180

Blodtrycksmanschett eller manuell handkompression vid bedömning av venös insufficiens i Vena saphena magna

Meerits, Jonna January 2011 (has links)
Bakgrund: Venduplex har på senare år vuxit fram som den mest använda metoden vid diagnostik av venös insufficiens eftersom det är en ofarlig, kostnadseffektiv, non-invasiv metod med hög sensitivitet och specificitet där både den anatomiska placeringen av insufficiensen samt den funktionella förändringen av venen kan påvisas direkt vid undersökningen. Olika manövrar kan genomföras för att påfresta venklaffarna och därmed framkalla en eventuell reflux, men det är oklart om de olika manövrerna kan påverka den reflux som provoceras fram och därmed också påverkar bedömningen av insufficiensgraden. Syfte: Syftet med studien var att undersöka om det förelåg skillnad i graderingen av insufficiensen samt om den maximala refluxhastigheten påverkades beroende på vilken manöver som användes för att framkalla en reflux. Metod: 20 v. saphena magna mitt på låret med påvisad reflux deltog i studien. Två upprepade mätningar genomfördes där venklaffarna provocerades med hjälp av en blodtrycksmanschett över vaden, med en manuell kompression över låret samt med en manuell kompression över vaden. Resultat: Den maximala refluxhastigheten blev 0,33±0,20m/s när en blodtrycksmanschett över vaden användes, 0,31±0,22m/s när en manuell handkompression över vaden användes samt 0,17±0,16m/s när en manuell lårkompression genomfördes. Slutsats: Ingen signifikant skillnad på maximal refluxhastighet kunde konstateras när en automatisk uppblåsbar blodtrycksmanschett över vaden jämfördes med en manuell handkompression över vaden. En signifikant högre maximal refluxhastighet konstaterades när en manuell vadkompression jämfördes med en manuell lårkompression.

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