| 1. |
- Blomberg, Lars, et al.
(författare)
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Electric Field Diagnostics in the Jovian System : Brief Scientific Case and Instrumentation Overview
- 2006
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Ingår i: Proceedings of the 6th IAA International Conference on Low-Cost Planetary Missions. ; , s. 335-340
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The Jovian plasma environment exhibits a variety of plasma flow interactions with magnetised as well as unmagnetised bodies, making it a good venue for furthering our understanding of solar wind - magnetosphere / ionosphere interactions. On an overall scale the solar wind interacts with the Jovian magnetosphere, much like at Earth but with vastly different temporal and spatial scales. Inside the Jovian magnetosphere the co-rotating plasma interacts with the inner moons. The latter interaction is slower and more stable than the corresponding interaction between the solar wind and the planets, and can thus provide additional information on the principles of the interaction mechanisms. Because of the wealth of expected low-frequency waves, as well as the predicted quasi-static electric fields and plasma drifts in the interaction regions between different parts of the Jovian system, a most valuable component in future payloads would be a double-probe electric field instrument. Recent developments in low-mass instrumentation facilitate electric field measurements on spinning planetary spacecraft, which we here exemplify.
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| 2. |
- Hossain, Akter, 1967-
(författare)
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Studies on Redox-proteins and Cytokines in inflammation and Cancer
- 2007
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The redox state in the cell plays a major role in determining vital functions and its major imbalance can lead to severe cell injury or death. Redox active proteins and cytokines involved in this process includes thioredoxin (Trx), protein disulfide isomerase (PDI), and tumor necrosis factor (TNF) superfamilies. Trx is a multipotent protein and key regulator of cellular redox balance operating in synergy with Trx reductase and NADPH (the Trx system). Trx has gene regulatory activity of several transcription factors. It also controls in a fascinating way redox-sensitive “on-off” decisions for apoptotic or hypertrophic pathways. Trx protects against H2O2 and TNFmediated cytotoxicity, a pathway in which TNF receptor-binding generates ROS. TNF is an autocrine growth factor and survival factor in vitro and in vivo for B-type of chronic lymphocytic leukemia (B-CLL) cells. The overall aim of this study was to investigate the importance of redox active proteins and cytokines in inflammation and cancer. We focused on: i) the role of Trx, TrxR, and selenium in carcinogenesis and in resistant cancer cells. ii) the importance of Trx in cancer cells and the redox regulation of TNF and its receptors TNFR1 and TNFR2. iii) the potential role of Trx as a key regulator in cellular redox balance, in the pathogenesis of cardiac dysfunction; its relationship to stress response parameters. iv) whether unmutated CLL (UCLL) responses to PKC and ROS pathways were different from mutated CLL (M-CLL) responses.Our results demonstrate pronounced selective selenium-mediated apoptosis in therapy resistant cells and suggest that redox regulation through the Trx system is an important target for cancer therapy. Trx was strikingly elevated in heart failure cases compared with controls signifying an adaptive stress response that is higher the more severe the disease. TNF autocrine release was redox modulated and the TNF receptors interacted at the cell surface membrane with the redox-active PDI, which excerted a stringent redox-control of the TNFR signaling. The proliferative response as well as increase of autocrine TNF and Trx were higher in U-CLL than in M-CLL.The overall conclusion of the four papers included in this thesis is that redox-active proteins and cytokines plays an important role in control and regulation of cancer and inflammation. Furthermore, redox regulation via thioredoxin by selenium, may offer novel treatment possibilities for resistant tumors disease.
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| 3. |
- Lindqvist, Anna, et al.
(författare)
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The odor perception of key degradation products of polyamide 6.6
- 2009
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Ingår i: Fechner Day 2009. - Galway, Irland : International Society for Psychophysics. ; , s. 335-340
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Psychophysical research on indoor air has not focused on the odor of degradation products of polymers in building materials, e.g. the polymer Polyamide 6.6. Three of its odorous degradation products, cyclopentanone, pentanoic acid, and 2-methyl-pyridine, were measured in the form of single chemical compounds and their four mixtures. The results from 15 participants’ scaling of perceived odor similarity and ranking of odor preference showed that the cyclopentanone odor is masked by the other odor(s) of its mixtures. A new odor quality was formed when pentanoic acid and 2-methyl-pyridine were mixed. The three chemical compounds, thus, provided for four unique odor qualities, as revealed in a PCA. Moreover, the odor intensity ranks confirmed intermediacy of odor mixtures relative to these same four unique odor qualities. Our results confirm the importance of degradation products of polyamide 6.6 as contributors to indoor air quality.
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| 4. |
- Lindqvist, Olav, 1961-
(författare)
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Att leva med kroppsliga förändringar vid obotlig cancersjukdom med fokus på prostatacancer : ”jag är frisk – bortsett från att jag har cancer som är dödlig, men det är liksom en annan sak”
- 2007
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The overall aim of this thesis is to illuminate and describe bodily changes and problems in incurable cancer, with focus on prostate cancer, from the patient’s perspective. The thesis consists of four papers, each of which illuminates various aspects of the phenomenon studied. The study population consisted of 24 participants, three women with different cancer diagnoses in the palliative phase, and 21 men with hormone refractory prostate cancer (HRPC) and skeletal metastases. Data are based on interviews (papers I–IV) and a quality of life questionnaire (paper I). The study design is cross-sectional (papers I–III) and longitudinal (paper IV). Qualitative description, descriptive statistics, phenomenological hermeneutics, and analysis of discourse were used to analyze data. The findings of study I show that the dominating symptoms for the men with HRPC (n=20) were pain and fatigue, and three different variants of each problem were described. The men said that changes in their sex life were not an extensive problem, even if it was scored as such. The symptoms differed in occurrence, extent, and meaning between the men, and were not necessarily experienced as problems. In study II, pain and fatigue were again the most prominent problems in men with HRPC (n=18), but pain and fatigue were seen to have different meanings. Pain was seen as synonymous with cancer. Pain can be alleviated, but it is a threat, both now and in the future, and symbolizes a painful death. Fatigue was viewed as a hindrance in the present. It was experienced as less threatening than pain, but as something that cannot really be changed. Fatigue represents the natural course death will take, as eventually sleep into death. An important finding of study II is that one meaning of bodily problems is to live in a cyclical movement of losing and reclaiming wellness. Understanding, and, to some extent, being in control of, bodily problems makes it possible to experience wellness. When the bodily problems increase or change, or when new problems appear or become a hindrance in the daily life, the experience of being ill returns. The findings of study III show that one meaning of fatigue in patients with cancer in the palliative phase (n=4) is a lived bodily experience of approaching death. This can be understood through the paradox of struggling against fatigue, and hoping to overcome it, yet expecting failure. The body, through fatigue, signals to the person that death is approaching, but the person is not yet “ready”. Paper IV shows that the way two of the men with HRPC talked about the past, present, and future changed during the disease trajectory. In the first interview, the men were open towards both the past and the future, while just before death, their narration was totally dominated by the concrete experience of the illness. The past became the past in the illness and not in life, and the present was flooded with extensive bodily changes. Also, the future had shrunk, although it also had been transferred to beyond death. Pain, fatigue, nausea, and other bodily problems figured largely in this change. This thesis provides important insights into the phenomenon of bodily changes when living with incurable cancer, with focus on prostate cancer. The thesis shows the connection between bodily changes and time, where different bodily changes have different meanings, and meanings seem to change during the illness trajectory (papers I–IV); and bodily changes close to death seem to take “all” time; what is left is the present filled with problems (paper IV). Further, it shows that bodily changes have a great influence on the cyclical movement between losing and reclaiming wellness in incurable cancer (paper II). The clinical implications of the thesis are that alleviation of pain and other bodily problems must be based on the meaning the patient gives the bodily changes taking place. That is, alleviation with the purpose to free time and to facilitate living in wellness as death is approaching.
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| 5. |
- Lindqvist, Per, 1960-
(författare)
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Right heart function in health and disease : a doppler echocardiography and doppler tissue imaging study
- 2005
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background: It is well known that performance of the right ventricle (RV) determines exercise capacity and may confer prognostic information in different cardiopulmonary diseases. To allow optimal patient management, ideal methods to assess right heart function are therefore important. Echocardiography is an attractive investigation for that purpose, although limited by the anatomical and functional complexities of the RV. The aim of the present thesis was to present applicable methods useful in clinical practice by traditional 2D/Doppler echocardiography and Doppler tissue imaging (DTI) in the assessment of global and regional RV function in both health and disease. Methods: The studies were performed on 4 different groups; (1) 255 healthy subjects (125 females), (2) 92 consecutive patients with different cardiac diseases (36 females), (3) 26 patients with systemic sclerosis, (SSc) (21 females) and (4) 26 consecutive patients with heart failure (8 females) undergoing cardiac catheterisation. Results: RV outflow tract fractional shortening (RVOT fs), which is a new method in the assessment of RV function, correlated significantly with RV systolic long axis motion (r= 0.66, p< 0.001), pulmonary artery acceleration time (r= 0.80, p< 0.001) and RV-right atrial peak systolic pressure drop gradient (r= -0.53, p< 0.001). Furthermore, RVOT fs was reduced in patients with pulmonary hypertension whereas RV systolic long axis motion was not in difference. This finding was confirmed after comparing RV function with invasive pressures. In healthy subjects, while the systolic myocardial velocities were preserved over age, the peak isovolumic contraction velocity (IVCv) was weakly increased with advanced age (r= 0.34, p< 0.01). Furthermore, both global and regional E/A ratios were reduced (r= -0.57, r= -0.67, p< 0.001 for both) with age whereas no alteration was found in the myocardial isovolumic relaxation time (IVRt). In patients with systemic sclerosis (SSc) both global (64± 23 vs. 39± 12 ms, p< 0.001) as well as regional (83± 40 vs. 46± 24 ms, p< 0.001) IVRt were prolonged. After evaluating echocardiographic parameters with invasive pressures we found a significant correlation between DTI derived IVRt and pulmonary artery systolic pressures (r= 0.83, p< 0.01) while the IVCv was related to the state of contractility (r= 0.77, p< 0.001). Furthermore, an IVCv below 6 cm/s was shown to be an accurate marker of increased right atrial pressure (>6 mm Hg). In conclusion, RVOT fs can be used as a complementary measurement of RV systolic function, being more sensitive to elevated pulmonary artery systolic pressures than the systolic longitudinal RV motion. Right heart function, mainly the diastolic function, is relatively weakly influenced by age compared to the left heart function. In patients with SSc, we found diastolic disturbances, including a prolonged IVRt and proposed the findings to be early markers related to intermittent pulmonary hypertension. This observation was strengthened after evaluating IVRt against invasive pulmonary artery systolic pressures. IVCv can be used to determine the state of RV contractility and also be used to identify patients with elevated filling pressures. The presented methods can be used to detect early signs of RV dysfunction which might prohibit right heart failure. All presented methods are non-invasive, reproducible, easy obtainable, and thus useful in clinical practice.
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| 10. |
- Wahlund, Jan-Erik, et al.
(författare)
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Cold Plasma Diagnostics in the Jovian System : Brief Scientific Case and Instrumentation Overview
- 2006
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Ingår i: Proceedings of the 6th IAA International Conference on Low-Cost Planetary Missions. ; , s. 341-346
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The Jovian magnetosphere equatorial region is filled with cold dense plasma that in a broad sense co-rotate with its magnetic field. The volcanic moon Io, which expels sodium, sulphur and oxygen containing species, dominates as a source for this cold plasma. The three icy Galilean moons (Callisto, Ganymede, and Europa) also contribute with water group and oxygen ions. All the Galilean moons have thin atmospheres with residence times of a few days at most. Their ionized ionospheric components interact dynamically with the co-rotating magnetosphere of Jupiter and for example triggers energy transfer processes that give rise to auroral signatures at Jupiter. On these moons the surface interactions with the space environment determine their atmospheric and ionospheric properties. The range of processes associated with the Jovian magnetospheric interaction with the Galilean moons, where the cold dense plasma expelled from these moons play a key role, are not well understood. Conversely, the volatile material expelled from their interiors is important for our understanding of the Jovian magnetosphere dynamics and energy transfer. A Langmuir probe investigation, giving in-situ plasma density, temperatures, UV intensity and plasma speed with high time resolution, would be a most valuable component for future payloads to the Jupiter system. Recent developments in low-mass instrumentation facilitate Langmuir probe in situ measurements on such missions.
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