| 1. |
- Hultin Jäderlund, Karin, et al.
(författare)
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Cerebrospinal Fluid PCR and Antibody Concentrations against Anaplasma phagocytophilum and Borrelia burgdorferi sensu lato in Dogs with Neurological Signs
- 2009
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Ingår i: Journal of Veterinary Internal Medicine. - : Wiley. - 0891-6640 .- 1939-1676. ; 23, s. 669-672
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Tidskriftsartikel (refereegranskat)abstract
- The tick-borne bacteria Borrelia burgdorferi sensu lato (sl) and Anaplasma phagocytophilum have been suspected to cause neurological signs in dogs. Diagnosis often has been made based on positive antibody titers in serum of dogs with neurological signs, but a high seroprevalence in dogs in at-risk populations makes diagnosis difficult.To determine if the neurological signs in dogs examined were caused by any of these bacteria.Fifty-four dogs presented to a board-certified neurologist.Prospective study. We divided dogs into 2 groups: those with inflammatory diseases of the central nervous system (CNS) and those with neurological signs from other diseases. Blood and cerebrospinal fluid (CSF) from all dogs were analyzed.Dogs with inflammatory CNS diseases showed no serum antibodies against any of the agents. Among dogs with neurological signs from other diseases, 10.3% had serum antibodies for B. burgdorferi sl and 20.5% for A. phagocytophilum. All blood samples analyzed for bacterial deoxyribonucleic acid (DNA) and all CSF analyzed for antibodies and bacterial DNA for the 2 agents were negative.Based on this study, these bacteria are unlikely causes of neurologic disease in dogs and the presence of serum antibodies alone does not document or establish a definitive diagnosis of CNS disease caused by these organisms. Dogs that have neurologic disease and corresponding serum antibodies against these agents should have additional tests performed to assess for other potential etiologies of the signs.
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| 2. |
- Macias Garcia, B., et al.
(författare)
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Single-Layer Centrifugation Through Colloid Positively Modifies the Sperm Subpopulation Structure of Frozen-Thawed Stallion Spermatozoa
- 2009
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Ingår i: Reproduction in domestic animals. - : Wiley-Blackwell. - 0936-6768 .- 1439-0531. ; 44:3, s. 523-526
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Tidskriftsartikel (refereegranskat)abstract
- The present study attempted to select the subpopulation of stallion spermatozoa that best survived a conventional freezing and thawing procedure, using centrifugation of post-thawed semen samples through a single layer of a glycidoxypropyltrimethoxysilane-coated silica colloid with a species-specific formulation (Androcoll-E (TM)). After freezing and thawing, four sperm subpopulations were identified, listed as FT1 to FT4. While subpopulations FT1 and FT2 were characterized by low sperm velocity, high velocities characterized the ones called FT3 and FT4. The single-layer centrifugation (SLC)-handled sperm sample was enriched in subpopulation FT3, reaching a proportion of 82.6% of the present spermatozoa, in contrast with the non-filtered control post-thawed semen, where this sperm subpopulation only accounted for 16.3% of the total. It is concluded that in the equine industry, the SLC is a practical, easy-to-perform approach to improve the quality of equine frozen-thawed semen samples.
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| 3. |
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| 4. |
- Löfgren, Magnus, 1979-
(författare)
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Behavioral effects of female sex steroid hormones : models of PMS and PMDD in Wistar rats
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background Animal models can be used to mimic human conditions of psychopathology, and also as pre-clinical models to evaluate candidate drugs. With hormonal treatment it is possible to produce behavior in the rat which corresponds to the mental symptoms of pre-menstrual syndrome (PMS), and pre-menstrual dysphoric disorder (PMDD). PMS affects 25-30 % of all women in fertile age and 3-8% are diagnosed with the more severe condition PMDD. The cardinal mental symptoms are; irritability, mood-swings, depression, anxiety, fatigue, insomnia, difficulties with concentration and memory and learning difficulties. The symptoms of PMS/PMDD occur in the luteal phase in conjunction with increasing concentrations of progesterone (P4) and P4-metabolites. In anovulatory cycles the symptoms are absent. The hormones which produce the monthly reoccurring negative symptoms on mood are foremost the neuroactive metabolites; allopregnanolone (ALLO) and tetrahydro-deoxycorticosterone (THDOC). ALLO is produced by the corpus luteum, but can also be synthesized in the brain, both ALLO and THDOC can also be released from the adrenal cortex during stress. These steroids are active on the inhibitory GABA neurotransmitter system through the GABAA receptor, and the effects are similar to that of alcohol and benzodiazepines. These steroids have strong sedative and hypnotic effects. A paradox is that some individuals seem to react with negative mood on sex steroids while all fertile women have the cyclical steroid changes during the menstrual cycle. Some individuals are more sensitive to neuroactive steroids with influences of personality, heritability and stress factors. Aims The thesis aims were to develop pre-clinical animal models of PMS/PMDD and to investigate induction of ALLO tolerance, individual sensitivity to neurosteroids and the interactions between chronic social stress and neurosteroids. Methods In these studies male and female Wistar rats were used to test steroid hormone effects on learning and memory and behaviors analogous to negative mood symptoms. This was accomplished through hormonal treatment and a subsequent withdrawal period from P4 (P4) + estradiol (E2) (PEWD), or ALLO. To assess tolerance, memory and learning in the Morris water maze (MWM) was studied. Anxiety-like behaviors were tested with the elevated plus maze (EPM), open field test (OFT), and the intruder test (IT). The EPM or OFT was used to classify the rats as high or low responders on risk-taking and explorative behavior (HR/LR). For social ranking order assessment the tube test (TT) and food competition test (FCT) were used. Chronic social stress was accomplished through co-habituation with two older rats (chronic subordination stress). In female rats the estrous cycle followed using staining of vaginal smears. Concentration of corticosterone (CORT) was measured by radio-immuno-assay (RIA). Results In the MWM ALLO pre-treatment produced tolerance to the acute negative ALLO effects. Both male and female rats showed behavioral correlations between the EPM and OFT tests, and correlations were also seen in CORT levels. Individuals with the stable trait of high risk-taking and explorative behavior (HR) were more sensitive to PEWD induction of anxiety-like behavior. These animals also showed decreased CORT levels during withdrawal. Chronic subordination stress enhanced the response to PEWD on measures of locomotor activity and social anxiety-like behavior. Conclusions It is possible to induce tolerance to the negative ALLO effects on learning and memory. The animal models of anxiety-like behavior show an individual PEWD response profile where HR rats are more sensitive. Exposure to chronic social stress enhanced the PEWD response. Hence there are both inherent and environmental factors behind the behavioral response to steroid hormones in rats.
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| 5. |
- Wanby, Pär
(författare)
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On certain genetic and metabolic risk factors for carotid stenosis and stroke
- 2006
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The present study evaluated genetic and metabolic factors influencing the risk of acute cerebrovascular disease (CVD) and internal carotid artery stenosis (ICA stenosis) in a Swedish community. The threonine (T) containing protein of the FABP2 A54T gene polymorphism has a greater affinity for long chain fatty acids (FFAs) than the alanine (A) containing protein. This altered affinity for FFAs has been shown to affect the intestinal absorption of fatty acids and consequently the fatty acid composition of serum lipids, in particularly postprandially. Endothelium derived NO is a potent vasodilator and antiatherogenic agent. Asymmetric dimethyl arginine (ADMA) is an endogenous competitive inhibitor of endothelial nitric oxide synthase (eNOS). ADMA has been shown to be involved in the pathogenesis of atherosclerotic disease, and ADMA inhibits eNOS by displacement of L-arginine from the enzyme, which in turn is believed to affect the amount of NO available within the endothelium.The FABP2 A54T gene polymorphism was analyzed in 407 patients with acute CVD and also in a subset of these patients whose carotids had been evaluated with ultrasound. Both the FABP2 polymorphism and a common polymorphism of the eNOS gene, Glu298Asp, were analyzed in a different population consisting of 54 matched pairs of patients with ICA stenosis and controls. ADMA levels were measured in both study populations.We found that the T54 allele was more frequent in patients with transient ischaemic attacks (TIA), and that the TT genotype was more prevalent in young, non-smoking patients with CVD than in controls.Increased concentrations of ADMA were observed in cardio-embolic infarction and TIA, but not significantly in non-cardio-embolic infarction nor in haemorrhagic stroke. In multivariate logistic regression models, CVD increased across quartiles of ADMA in all subgroups, but this association was only significant in the TIA group. A decreased arginine/ADMA ratio, a measure of NO availability was associated with CVD in the entire study population. Patients with severe carotid stenosis had significantly higher ADMA levels than the controls. Allele and genotype frequencies of the FABP2 and eNOS polymorphisms did not differ between patients with ICA stenosis and controls.Our results indicate that ADMA is a strong marker for TIA and severe ICA stenosis, and that relative defiency of arginine, measured as L-arginine/ADMA, is present in acute CVD.We also conclude that a common polymorphism of the FABP2 gene increases susceptibility to ischaemic stroke and TIA.
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| 6. |
- Andersson, Gunnel, 1958-
(författare)
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Urinary incontinence : prevalence, treatment seeking behaviour, experiences, and perceptions among persons with and without urinary leakage
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The overall aim of this thesis is to describe urinary incontinence (UI) from a population perspective and to describe experiences and perceptions of UI from an individual perspective. This includes assessing the prevalence of urinary incontinence as well as describing treatment seeking and experiences of living with UI. A secondary aim was to describe the perception of UI among cultures other than the Swedish mainstream, exemplified in this case by Syrian women living in Sweden. Both quantitative and qualitative methods were used, including questionnaires and interviews. Studies I and II were quantitative studies based on a population-based study. Together with a postal survey on general health and living conditions “Life & Health”, a questionnaire on urinary incontinence was sent out to 15 360 randomly-selected residents aged 18-79 in Orebro County, Sweden. In Study I, UI was found to affect 19%. The majority of the respondents experienced minor problems, and only 18% of those reporting UI wanted treatment. However, there was also a group who reported severe problems, but despite this 42% of them did not want treatment. Study II investigated why people with UI refrain from seeking care and treatment. It was found that the desire for treatment was regulated by the frequency of UI, being restricted from participating in various activities, the degree of inconvenience, and the type of UI. Studies III and IV were both qualitative interview studies, describing older women’s experiences of living with UI (Study III) and Syrian women’s perceptions of UI (Study IV). There were similarities between the results of these two studies; the women described UI as a normal and expected problem, and they knew that the district nurse could prescribe incontinence protections and that treatments existed. In both studies, the women expressed difficulties in making contact with the health care service, while the women who did not speak Swedish (Study IV) also had difficulties due to different communication problems. In conclusion, it is important that health care resources are optimized to identify and meet the needs of those who experience major problems with UI, and that there is awareness of the communication difficulties that can be present in meeting with people who speak other languages. However it is also important not to medicalize those who experience minor problems and who have the desire to manage on their own.
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| 7. |
- Gareis, Daniel, et al.
(författare)
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Mouse MRI using phased-array coils
- 2007
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Ingår i: NMR in Biomedicine. ; 20:3, s. 326-334
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Tidskriftsartikel (refereegranskat)abstract
- The advantages of array coil imaging in human whole-body MR systems are well known and have gained relevance in many applications and MR techniques. In the field of small-animal studies, this concept has become increasingly important. In this work, three different phased-array coils for performing MRI on mice are presented. For imaging at 300 MHz, a four-channel receive-only phased-array coil is introduced. One two-channel and a four-channel transmit/receive setup operating at 750 MHz show the feasibility of array coil imaging at 17.6 T. All of these coils show excellent performance and deliver high-quality MR images of mice.
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| 8. |
- Türkmen, Sahruh, et al.
(författare)
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Tolerance development to Morris water maze test impairments induced by acute allopregnanolone
- 2006
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Ingår i: Neuroscience. - : Elsevier Inc.. - 0306-4522 .- 1873-7544. ; 139:2, s. 651-659
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Tidskriftsartikel (refereegranskat)abstract
- The progesterone metabolite allopregnanolone, like benzodiazepines, reduces learning and impairs memory in rats. Both substances act as GABA agonists at the GABA-A receptor and impair the performance in the Morris water maze test. Women are during the menstrual cycle, pregnancy, and during hormone replacement therapy exposed to allopregnanolone or allopregnanolone-like substances for extended periods. Long-term benzodiazepine treatment can cause tolerance against benzodiazepine-induced learning impairments. In this study we evaluated whether a corresponding allopregnanolone tolerance develops in rats. Adult male Wistar rats were pretreated for 3 days with i.v. allopregnanolone injections (2 mg/kg) one or two times a day, or for 7 days with allopregnanolone injections 20 mg/kg intraperitoneally, twice a day. Thereafter the rats were tested in the Morris water maze for 5 days and compared with relevant controls. Rats pretreated with allopregnanolone twice a day had decreased escape latency, path length and thigmotaxis compared with the acute allopregnanolone group that was pretreated with vehicle. Pretreatment for 7 days resulted in learning of the platform position. However, the memory of the platform position was in these tolerant rats not as strong as in controls only given vehicle. Allopregnanolone treatment was therefore seen to induce a partial tolerance against acute allopregnanolone effects in the Morris water maze.
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| 9. |
- Akanda, Nesar, 1972-
(författare)
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Voltage-dependent anion channels (VDAC) in the plasma membrane induce apoptosis
- 2006
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Apoptosis, or programmed cell death, is essential for proper development and functioning of the body systems. During development, apoptosis plays a central role to sculpt the embryo, and in adults, to maintain tissue homeostasis by eliminating redundant, damaged or effete cells. Therefore, a tight regulation of this process is essential. Cell shrinkage associated efflux of K+ and Cl– through plasma membrane ion channels is an early event of apoptosis. However, little is known about these fluxes. The aim of this thesis was to investigate ion channels in the plasma membrane of neurons undergoing apoptosis. We studied differentiated (the mouse hippocampal cell line HT22, the human neuroblastoma cell line SK-N-MC, and rat primary hippocampal neurons) and undifferentiated (rat primary cortical neural stem cells cNSCs) cells with the patch-clamp technique. All cell types displayed a low electrical activity under control conditions. However, during apoptosis in differentiated neurons, we found an activation of a voltage-dependent anion channel. The conductance of the channel is 400 pS, the voltage dependence of the opening is bell shaped with respect to membrane voltage with a maximum open probability at 0 mV, and the Cl− to cation selectivity is >5:1. These biophysical properties remind about the voltage-dependent anion channel normally found in the outer mitochondrial membrane (VDACmt). Hence, we call our apoptosis-inducing plasma membrane channel VDACpl. The molecular identity of the channel was corroborated with the specific labelling of different anti-VDAC antibodies. Block of this channel either with antibodies or with sucrose prevented apoptosis, suggesting a critical role for VDACpl in the apoptotic process. VDACpl is a NADH (-ferricyanide) reductase in control cells. We found that the enzymatic activity is altered while the VDACpl channel is activated during apoptosis. Surprisingly, in cNSCs we did not find any activation of VDACpl, no VDACpl-specific labelling, no enzymatic activity, and no prevention of apoptosis with VDACpl-blocking strategies. Instead, we found an activation of a voltage-independent 37 pS ion channel, and that the Cl– channel blocker DIDS prevented apoptosis in cNSCs. Our finding that activation of VDACpl is critical for apoptosis in differentiated neurons hopefully can lead to new strategies in the treatment of several diseases related to apoptosis.
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| 10. |
- Anderzén-Carlsson, Agneta, 1966-
(författare)
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Children with cancer : focusing on their fear and on how their fear is handled
- 2007
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Various fears in children with cancer have previously been identified as a result of studying e.g. symptom experiences, distress and uncertainty within this population. Studies of the meaning the children give to their fear, as well as the handling of their fear seem to be sparse, however. Also, fear has not been an exclusive focus in previous studies. Professionals in clinical practice have pointed to the need for such research, which has prompted the present research work. The overall aim of this thesis was therefore twofold; firstly, the aim was to elucidate fear in children and adolescents with cancer in order to gain an understanding from the perspective of adolescents and parents. Secondly, it was to elucidate parents’ and professionals’ handling of the fear. This in order to gain a deeper understanding of what performances and manners the children and adolescents can face when being fearful. A qualitative descriptive design was adopted in the five included studies. The methods used in the data analysis were phenomenological hermeneutical method (studies I–III) and qualitative content analysis (studies IV–V). In study I six adolescent girls, aged 14–16 years, with experiences of various cancer diagnoses, but now declared fit, were interviewed. The results reveal that they experience their fear as embodied, which in the comprehensive understanding of the results was interpreted as a threat to their personal self, their whole existence. Their fear was seen as a holistic intertwined experience, including fear related to the physical body and to the social self. Also, existential fear was described. Their described experience was interpreted as suffering. Studies II and III share the same data. Fifteen parents of children at various ages with various cancer diagnoses were interviewed in focus groups about their experience of their child’s fear. In study II the result reveals how the parents experienced and understood their child’s fear. The fear was described as a multidimensional phenomenon, which was not always easy to identify. It was contrasted to feelings of unease and to absence of fear. In the comprehensive understanding the fear was interpreted as a suffering, as that was regarded to be what was the common meaning in the narratives. The suffering was interpreted as an ethical demand to the parents to take action. In study III the parents described their actions, i.e. they described how they dealt with the fear. Their actions were described as acting in the best interests of the child, which included striving to make the child feel secure and experience wellbeing, up to a certain point. However, after this point the parents used their parental authority to maintain the child’s physical health rather than trying to prevent or relieve the child’s fear. In the comprehensive understanding the parents’ handling of their child’s fear was interpreted as revealing mercy and as being synonymous with meeting the ethical demand put on them. In study IV ten experienced nurses and physicians were individually interviewed about how they handled fear in children with cancer. The result reveals that the existential issues were dealt with within the relationship with the child, on a sliding scale between closeness and distance, and that the fear related to medical procedures occurred on a continuum between support and lack of support. The various actions involved, and the manner in which these actions were performed, was described. In the observational study (study V) eleven parents and their children as well as eleven health professionals participated. They were observed at children’s routine visits at the outpatient clinic. The aim was to study the interactions related to fear. The result reveals that when children were fearful they expressed this both verbally and non-verbally. The parents’ and professionals’ actions and interactions in these situations were found to be characterized by recognition of the fear or lack of attention to the fear. The findings can contribute to a broadened knowledge on fear in children and adolescents with cancer. Awareness and understanding of the meaning adolescents give to their fear, and furthermore, of the parents’ experience and understanding of their child’s fear can provide tools for interacting with these groups. The findings on how fear is dealt with by the ones children have claimed as important sources for support, can give insights into what the child may face when being fearful. These insights can form the basis for individual, as well as collegial, reflections on what is done when children face fear, how fear is handled on an everyday basis and why it is handled in this way. Such reflections could lead to an ethical awareness of handling fear in children with cancer.
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