| 1. |
- Borgfeldt, Christer, et al.
(författare)
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High tumor tissue concentration of urokinase plasminogen activator receptor is associated with good prognosis in patients with ovarian cancer
- 2003
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Ingår i: International Journal of Cancer. - : Wiley. - 0020-7136. ; 107:4, s. 658-665
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Tidskriftsartikel (refereegranskat)abstract
- volved in tumor growth and metastasis. We assayed the components of the uPA system in homogenates of 64 primary epithelial ovarian tumors and 5 metastases and evaluated the association of these parameters to prognosis in the 51 malignant cases. The levels of uPA, PAI-2 and the uPA: PAI-I complex increased with progressive loss of histological differentiation (P-trend <0.001, <0.05 and <0.001). The level of PAI-I was higher in poorly than in well/moderately differentiated tumors (p = 0.03). The content of uPAR was lower in benign tumors as compared to borderline malignancies (p = 0.002), invasive primary tumors (p < 0.001), and metastases (p = 0.002). Surprisingly, the level of uPAR was lower in poorly differentiated as compared to both borderline (p = 0.01) and well differentiated malignant tumors (p = 0.005). Also, the level of uPAR was lower in advanced as compared to early stages of the disease (P-trend = 0.002). The median follow-up time for patients was 5.8 years. High tumor tissue levels of uPAR were associated with longer postoperative survival (HR = 0.4, 95% CI = 0.2-0.8, p = 0.01). In contrast, shorter survival was evident in patients with high tumor levels of uPA from 2 years on after operation (HR = 4.6, 95% CI = 1.2-17, p = 0.02). High tPA levels tended to be associated with shorter overall survival after 2 years (HR = 2.9, 95% 95% Cl = 0.9-9.8, p = 0.08). Although high tumor tissue content of uPAR was associated with a less aggressive phenotype characterized by well differentiated histology and longer survival, low content of uPAR in the poorly differentiated tumors and metastases presumably results from increased elimination of uPAR. (C) 2003 Wiley-Liss, Inc.
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| 2. |
- Brun, Eva, et al.
(författare)
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Prognostic value of histopathological response to radiotherapy and microvessel density in oral squamous cell carcinomas
- 2001
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Ingår i: Acta Oncologica. - : Informa UK Limited. - 1651-226X .- 0284-186X. ; 40:4, s. 491-496
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Tidskriftsartikel (refereegranskat)abstract
- The prognostic value of histopathological response to preoperative radiotherapy (50 Gy) in radically resected oral carcinomas was studied in 39 consecutive patients. Microvessel density (MVD) was evaluated for relation to radioresponse and outcome. Resected tumour tissue was examined histopathologically and response to radiotherapy was scored according to induced morphological changes. Pretreatment biopsies were stained with antibodies to von Willebrand factor to evaluate MVD in hot-spot regions, in stromal tissue and in tumour epithelial tissue. Histopathological response to radiotherapy was highly prognostic of local failures and survival (p = 0.002), though microscopic surgical radicality was obtained. In good responders to preoperative radiotherapy, the 5-year survival rate was 68% compared with 24% in poor responders. In 12 patients with local recurrence after radical surgery, 11 had poor histopathological radiotherapy responses. In univariate analysis, a high MVD score in tumour epithelium was associated with poor clinical outcome but MVD did not correlate with histopathological radiotherapy response.
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| 3. |
- Dahlgren, Eva, et al.
(författare)
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Sertoli-Leydig cell tumour in a postmenopausal woman showing all facets of the insulin resistance syndrome (IRS)
- 2005
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Ingår i: Ups J Med Sci. - 0300-9734. ; 110:3, s. 233-6
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Tidskriftsartikel (refereegranskat)abstract
- Sertoli-Leydig cell tumours are rare sex stromal tumours with an incidence of < 0.5% of all ovarian tumours. Most frequently this tumour occurs in young women with a history of amenorrhoea, hirsutism and lowered pitch. Here, we report on a woman with IRS, postmenopausal virilization and increased testosterone levels due to a Sertoli-Leydig cell tumour. This is the first case to suggest an association between IRS and Sertoli-Leydig cell tumours. Furthermore, we highlight the difficulties in detecting this ovarian tumour with sonography.
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| 4. |
- Eriksson, Lars, et al.
(författare)
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Miljöövervakning i Mälaren 2002
- 2003
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- På uppdrag av Mälarens vattenvårdsförbund har Institutionen för miljöanalys vid SLU iUppsala utfört provtagning, analys och utvärdering av vatten i Mälarens fjärdar under år2002.Föreliggande årsredogörelse beskriver huvuddragen av resultaten som dessutom bifogas i sinhelhet i tabellform. En fristående sammanfattning på 8 sidor har dessutom producerats ochdistribuerats.
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| 5. |
- Fernö, Mårten, et al.
(författare)
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Improved preparation technique of cervical carcinoma for flow cytometric DNA analysis with tissue disintegration in hydrochloric acid
- 1990
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Ingår i: In Vivo. - 0258-851X. ; 4:4, s. 225-229
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Tidskriftsartikel (refereegranskat)abstract
- An one-step procedure using a nuclear isolation medium containing propidium iodide has been found to be a suitable preparation technique for flow cytometric DNA analysis in breast cancer samples. In the case of cervical squamous carcinoma, a pretreatment with HCl seems to be a methodological improvement. One advantage with the HCl modification is that some "false" near-diploid cell populations are abolished. These "false" G0/G1 peaks may represent diploid nuclei with a different stainability for propidium iodide compared to normal diploid nuclei. The HCl treatment has, furthermore, the advantage of increasing the elution of nuclei (mean factor of 4.0), especially non-diploid nuclei from higher differentiated squamous carcinomas.
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| 6. |
- Fredstorp-Lidebring, M, et al.
(författare)
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Urokinase plasminogen activator and its inhibitor, PAI-1, in association with progression-free survival in early stage endometrial cancer
- 2001
-
Ingår i: European Journal of Cancer. - 1879-0852. ; 37:18, s. 2339-2348
-
Tidskriftsartikel (refereegranskat)abstract
- Components of the urokinase plasminogen activator (u-PA) system are involved in the metastatic process, and have accordingly been associated with clinical outcome in a variety of malignant tumours. We investigated the prognostic importance of u-PA and plasminogen activator inhibitor type 1 (PAI-1) in endometrial cancer, analysed with luminometric immunoassay (LIA) and enzyme-linked immunosorbent assay (ELISA), respectively. Two different cut-off levels were used: the median and the 80th percentile-the latter because of the low progression rate for patients with early stage (I-II) endometrial cancer. After a median follow-up time of 6.8 years, univariate analysis of patients with stage I-II disease (n=188) showed that high u-PA and high PAI-1 content was associated with a shorter progression-free survival (PFS), but at different cut-off levels, uPA at the median (P=0.003), and PAI-1 at the 80th percentile (P<0.001). Among the other factors, DNA ploidy status was most strongly correlated to PFS, followed by age (continuous), International Federation of Gynaecology and Obstetrics (FIGO) grade of differentiation, S-phase fraction and progesterone receptor (PgR) status. Bivariate analyses, including ploidy and one of the factors u-PA or PAI-1, showed that both add significant prognostic information. We conclude that u-PA and PAI-1 are promising prognostic factors in early stage endometrial cancer.
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| 7. |
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| 8. |
- Holmberg, Charlotte, 1972-
(författare)
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Så är det ju - den blir aldrig färdig! : En etnografisk studie om förskolepedagogers arbete med pedagogisk dokumentation
- 2015
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This dissertation is about educators work with pedagogical documentation in Swedish preschools. The purpose has been to investigate how pedagogical documentation is realized in everyday work in two preschools and examine how educators express themselves on purposes, opportunities and difficulties with this approach. This has been important to study since many preschools have chosen to work with pedagogic documentation to follow up and assure the quality of their work. Since 2010 pedagogical documentation is included in the preschools curriculum. The study was conducted at two different preschools where I followed a total of six educators in two preschool departments for two months in each department. Methods used to collect data were selected based on an ethnographic approach. Data collection consists of field notes, photographs, recorded interviews and documentations from preschools and their working plans. The analysis is based on a curriculum theory perspective, and especially important concepts have been transformation arena and realization arena. Furthermore, frame factor theory and the didactic questions what, how and why, have been used to analyze data. The results show that the documentation works where formulated in different ways depending on the frames and conditions. One preschool unit was at a municipal preschool without any special pedagogical approach. Here the pedagogical documentation was in a startup phase and was one of many tasks in the pedagogical work. The other preschool unit was in a Reggio Emilia inspired preschool who had worked with pedagogical documentation for several years. Here the work with pedagogical documentation was the driving force for developing the work. This ideological difference was reflected in what the educators documented, how they documented and how the documentations were used. Pedagogical documentation was partly be seen as a cumbersome way of working among the participants, whether they are beginners or experienced. It is in the nature of the work with pedagogical documentation that there are no obvious answers, which can lead to some uncertainty whether one is right or not. Other factors leading to frustration is that this approach is time-consuming and that the new technologies available require a lot of skills to be used. The study highlights that continuous training plays a crucial role as one of educator’s preconditions to succeed in the work with pedagogical documentation. In this study, one can also see how ethical aspects constantly makes themselves felt and need to be highlighted. The main impression is that the educators, despite the perceived difficulties, felt that it was stimulating and meaningful to work with pedagogical documentation and that they saw it as a tool for developing their work.
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| 9. |
- Hörnström, Einar, 1940-
(författare)
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Phytoplankton in Swedish oligotrophic lakes, affected by acidification, metals and liming
- 1999
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Anthropogenic airborne acidification has seriously affected thousands of lakes in Sweden, an alarming fact which was first noticed in the early 1970s, when pH had decreased to values below 5, especially in areas poor in limestone such as the Swedish west coast. This development was critical to phytoplankton, the diversity of which being markedly reduced, and where the groups Cyanophyceae, Bacillariophyceae and Conjugatophyceae were totally eliminated. A study of 500 lakes showed that this change was largely a result of low pH, since rather few species are acidophilic or acidotolerant. Secondary effects of acidification, such as phosphorus depletion and aluminium toxicity, however, were just as important, giving a combined stress upon the whole phytoplankton community, resulting in reduced species diversity. A large-scale remedial operation started in the middle of the 1970s, when the pH in many acidified lakes was increased to circumneutral values by addition of lime, in order to restore the original biotic communities. In several west coast lakes studied during 1973-1992, where the pH-values increased from 4.5-5.5 to 6.8-7.6, the treatments decreased the Al-levels and increased the concentrations of humic compounds and phosphorus in parallel with the decreased water transparency, compared with levels before liming. After a colonization period of 2-5 years, the species richness was fairly similar to that in unacidified lakes, and the species composition achieved indicated increased production. Results from long-term investigations in several limed lakes, and single analyses from other limed lakes, altogether making up a total of 63 limed lakes studied, were compared with the phytoplankton composition in 500 unlimed lakes. This showed that some species, common in unacidified lakes, were still missing several years after liming. Moreover, the original composition was not fully restored, results that could partly be explained by temporarily extreme pH-values and remaining ultraoligotrophic conditions. Regarding the consequences to the lake ecosystem, the absence of a few quantitatively unimportant species, however, does not seem to be a critical shortage.The toxicity of metals is one of the main stress factors depressing phytoplankton in lakes. The increased concentrations of inorganic and labile aluminium, caused toxic conditions that especially affected diatoms, chlorophyceans and desmids, and which were a main factor determining species composition in acidic lakes. Al-toxicity may occur temporarily also in neutral waters. Thus, laboratory tests showed that Monoraphidium griffithii was just as sensitive at pH 7 as at pH 4.8. In unacidified waters, increased concentrations of copper and zinc were recorded in connection with leakage from old mine tailings. During investigations in 41 and 32 lakes in 1992-1993 it was found that concentrations > 3-5 mg Cu l -1 and > 30 mg Zn l -1could be critical to some phytoplankton species. In the most contaminated lakes, with 1100-1500 mg Zn l -1 or 60-65 µg Cu l -1, the number of taxa was decreased by ca 50 %, but several species were frequent, indicating especially high tolerance. The lake waters were biologically characterized by algal assays. In the inorganic medium, the growth of Selenastrum capricornutum was strongly depressed at 1-2 mg Cu l -1, to be compared with 3-6 mg l -1 in lake waters with uncoloured substances, and 13-22 mg l -1 in waters with humic compounds. On the other hand, there was a positive relation between the number of diatom taxa and the manganese concentration.
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| 10. |
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| 11. |
- Isaksson, Johan, et al.
(författare)
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Highly elevated systemic inflammation is a strong independent predictor of early mortality in advanced non-small cell lung cancer
- 2022
-
Ingår i: Cancer Treatment and Research Communications. - : Elsevier. - 2468-2942. ; 31
-
Tidskriftsartikel (refereegranskat)abstract
- BackgroundAmple evidence support inflammation as a marker of outcome in non-small cell lung cancer (NSCLC). Here we explore the outcome for a subgroup of patients with advanced disease and substantially elevated systemic inflammatory activity.MethodsThe source cohort included consecutive patients diagnosed with NSCLC between January 2016 – May 2017 (n = 155). Patients with active infection were excluded. Blood parameters were examined individually, and cut-offs (ESR > 60 mm, CRP > 20 mg/L, WBC > 10 × 109, PLT > 400 × 109) were set to define the group of hyperinflamed patients. A score was developed by assigning one point for each parameter above cut-off (0–4 points).ResultsHigh systemic inflammation was associated with advanced stage and was seldom present in limited NSCLC. However, the one year survival of patients in stage IIIB-IV (n = 93) with an inflammation score of ≥2 was 0% compared to 33% and 50% among patients with a score of 1 and 0 respectively. The effect of a high inflammation score on overall survival remained significant in multi-variate analysis adjusted for confounding factors. The independent hazard ratio of an inflammation score ≥ 2 in multi-variate analysis (HR 3.43, CI 1.76–6.71) was comparable to a change in ECOG PS from 0 to 2 (HR 2.42, CI 1.13–5.18).ConclusionOur results show that high level systemic inflammation is a strong independent predictor of poor survival in advanced stage NSCLC. This observation may indicate a need to use hyperinflammation as an additional clinical parameter for stratification of patients in clinical studies and warrants further research on underlying mechanisms linked to tumor progression.
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| 12. |
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| 13. |
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| 14. |
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| 15. |
- Larson, Daniel, et al.
(författare)
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Bioaccumulation of microcystins in the food web : a field study of four Swedish lakes
- 2014
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Ingår i: Inland Waters. - 2044-2041 .- 2044-205X. ; 4:1, s. 91-104
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Tidskriftsartikel (refereegranskat)abstract
- The transfer of microcystins (MC) up the food chain was measured in 4 lakes in central Sweden; Ekoln, Lilla Ullfjärden, Valloxen, and Storsjön. In lakes Ekoln and Valloxen, Microcystis aeruginosa was the dominant cyanobacterium, while the oscillatorian species Planktothrix prolifica form dense blooms in Lake Lilla Ullfjärden. The cyanobacterial composition in Lake Storsjön was more diverse with several Microcystis andDolichospermum species. All dominant taxa are well-known producers of hepatotoxic MC. The highest recorded MC in the water samples from Lake Lilla Ullfjärden was measured in the bloom of P. prolifica (35 µg L−1). The highest MC content was measured in invertebrates; however, the MC concentration was usually low in fish. Maximum levels were 9 µg g−1 dry weight (dw) in zooplankton, 10 µg g−1 dw in benthos, and 2.7 µg g−1 dw in fish (smelt) liver. In fish muscle the highest recorded levels were 0.10–0.18 µg g−1 dw in bleak and smelt from Lake Lilla Ullfjärden and in pike-perch and roach from Lake Storsjön. Based on the World Health Organization’s tolerable daily intake value of 0.04 µg kg−1 body weight, we conclude that any risk related to MC from human consumption of fish from these lakes is minimal.
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| 16. |
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| 17. |
- Martín-Bylund, Anna
(författare)
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Towards a minor bilingualism : Exploring variations of language and literacy in early childhood education
- 2017
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The aim of this compilation thesis is to explore variations in bilingualism with the help of everyday specific situations at a Spanish-Swedish early childhood institution in Sweden, and by means of a ‘material-semiotic theorizing’. This means that material and semiotic elements are treated equally and entwined. Through studying a bilingual preschool practice, theory and politics as three interwoven practices, the thesis produces knowledge on language and literacy as socially and materially divergent, transformative occurrences. The research process is a commitment with Deleuzio-Guattarian philosophy, theory and politics, and is defined as a becoming in and of the three practices (education, theory, politics). Ethical and methodological undertakings are described as results of the interaction of these practices. Processes of data production include a yearlong fieldwork with all year groups (1-5) at a bilingual preschool in Sweden with a Spanish-Swedish language policy. The materials of data (approx. 59 hours of video-recordings and additional field-notes of everyday activities) are extended and developed upon in interaction with theoretical concepts and political concerns in terms of an analytical process that ‘puts theory to work’. The results are phrased as three temporal suggestions: 1) Bilingualism is a plural, collectively produced, both transitory and specific phenomenon 2) Bilingualism emerges with different, simultaneous dimensions of language and literacy (language as both code and material intensities) 3) Bilingualism is shared and public but also private and inconclusive. The thesis also shows the interconnectedness and continuity between different constructions of bilingualism (i.e. separate – flexible, public - private) as well as the productivity of the unknown and of what is labelled as (il)literate expertise. The impact that these suggestions may have in working with bilingualism in early childhood education is discussed. At the same time the discussion inspires to thinking towards a minor bilingualism also in more general terms.
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| 18. |
- Mputu, Adele, et al.
(författare)
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Fish populations and biomass in headwater streams of the Lake Tumba Landscape, DR Congo, 2007–2011
- 2022
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Ingår i: Acta Ichthyologica et Piscatoria. - : Pensoft Publishers. - 0137-1592 .- 1734-1515. ; 52, s. 195-208
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Tidskriftsartikel (refereegranskat)abstract
- The fish biodiversity in the Congo River and its tributaries is extremely rich but the information on fish communities in the headwaters in terms of catch and biomass estimates is rare. Fishes in the running and stagnant waters in this region are of vital importance as a food resource for local residents. This study aimed to describe the fish community, catch, and biomass in the three headwater streams Bambou, Lebomo, and Bongo in the Lake Tumba Landscape (LTL) of the Democratic Republic of the Congo. Such information is of vital impor- tance as a benchmark to understand the sustainability of the fish population for future generations of residents of the LTL. The field data were collected from 2007 through 2011, including dry and wet seasons. Here we present the results of this systematic, multi-annual study which was the first for fishes in streams of this region. In total, 50 species of 15 families were found in the nutrient-poor brown waters of these streams where high concentrations of humic acids cause a low pH. Among abundant species occurring in all three streams were the cyprinid Enteromius holotaenia (Boulenger, 1904), the mormyrid Marcusenius moorii (Günther, 1867), the alestids Clupeocharax schoutedeni Pellegrin, 1926 and Bryconaethiops boulengeri Pellegrin, 1900, and the clariid Clarias angolensis Steindachner, 1866. Bon- go Stream was distinguished from the others by a rich abundance of Alestopetersius compressus (Poll et Gosse, 1963). The presence of several species at low pH (between 5.0 and 5.5) is new information that lowers the bottom of the pH interval for these species compared to earlier reports. The maximum total length (TL) of some other species was by 5–20 percentage points higher than those reported earlier. The median weight per unit effort (WPUE) in the streams varied between 30 and 115 g per hour during the dry seasons and between 18 and 86 g per hour during the wet seasons. The fish biomass in the streams varied between 0.05 and 0.7 g ⸱ m–2 with a median 0.14 g ⸱ m–2. This relatively low value compared to other tropical headwaters may be a result of the low pH and dark color of these headwaters. The results of the study serve as a reference point to which future monitoring of fish fauna can be compared for sustainable management of the LTL
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| 19. |
- Ottosson, Lillit, 1988-
(författare)
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From Welfare to Work : Financial Incentives, Active Labor Market Policies, and Integration Programs
- 2022
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Essay I: I study the effects of increased social assistance (SA) generosity by exploiting exogenous variation induced by a ruling in the Swedish Supreme Administrative Court in 1993, mandating local governments to provide a minimum level of untied SA payments. The new rule forced some local governments to increase their SA generosity, while others were unaffected as they already complied with the stricter standards. I find that a 1 percent increase in SA generosity caused an increase in SA recipiency by 1.3 percent and a decrease in employment by 0.2 percent, among individuals with a high risk of receiving SA. For individuals who were already recipients of SA, the increase in SA payments was not offset by lower labor earnings, resulting in increased disposable income.
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| 20. |
- Persson, Gunnar, et al.
(författare)
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Miljöövervakning i Mälaren 2003
- 2004
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- På uppdrag av Mälarens vattenvårdsförbund har Institutionen för miljöanalys vid SLU i Uppsala utfört provtagning, analys och utvärdering av vatten i Mälarens fjärdar under år 2003.Föreliggande årsredogörelse beskriver huvuddragen av resultaten som dessutom bifogas i sinhelhet i tabellform. En fristående sammanfattning på 4 sidor har dessutom producerats och distribuerats.
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| 21. |
- Petersen, Petra, 1979-
(författare)
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Delaktighet och digitala resurser : Barns multimodala uttryck för delaktighet i förskolan i flerspråkiga områden
- 2020
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Children's different expressions of agency when using digital tablets in preschools in multilingual areas are explored in this study. Drawing on ideas problematizing the mono-lingual norm in western education (Björk-Willén, Gruber & Puskás, 2013; García, 2009; Kultti, 2012), the understanding is broadened of children's use of e.g. multilingual applications in ongoing projects. The use of digital resources in pedagogical documentation (c.f. Lenz Taguchi, 2013) is also in focus and children’s processes of creating their own documentation using digital tablets are discussed.Using a social semiotic approach (Kress, 1997; Selander & Kress, 2010) where children's multimodal communication is in focus, in combination with the notion of translanguaging (García, 2009), makes it possible to explore both multimodal and multilingual aspects of young children’s agency in day-to-day activities.Qualitative video observations of children as well as multimodal focus groups with teachers were used to reflect multimodal interaction between peers as well as with the tablet. Wireless recordings of the tablet screen were made when possible. Consolidating formal ethical guidelines (Vetenskapsrådet, 2017), particular ethical problems concerning informed consent when filming children were addressed proactively communicating with the children before and during the video recording process and allowing them to participate in the process of data collection if they wanted to.Incorporating other modes than verbal majority language using the affordances emerging in the use of digital tablets, children were able to express agency in both multilingual and multimodal ways. Photographical and portable modes were used by the children to create their own documentation and verbal content beyond the majority language, in applications including online and locally created resources where parents were co-producers.The added difficulty of expressing agency as both a young child and as a speaker of a minority or non-majority language, is discussed. The use of multimodal digital resources to create translanguaging activities might serve to overcome the specific challenges these children face. In a diverse world, where multilingual children have a right to communicate in all languages, the results could propose new ways of thinking about children’s agency and translanguaging activities in preschool.
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| 22. |
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| 23. |
- Weyhenmeyer, Gesa, et al.
(författare)
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Shifts in phytoplankton species richness and biomass along a latitudinal gradient : consequences for relationships between biodiversity and ecosystem functioning
- 2013
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Ingår i: Freshwater Biology. - : Wiley. - 0046-5070 .- 1365-2427. ; 58:3 (SI), s. 612-623
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Tidskriftsartikel (refereegranskat)abstract
- 1. Analysing phytoplankton community data from 205 small, mainly oligotrophic Swedish lakes along a 13 degrees latitudinal gradient, we found that the duration of the open-water season (DT>0) was best related to phytoplankton speciesrichness and biomass, probably because DT>0 can be used as a proxy for nutrient concentrations, as well as for light and temperature conditions in lakes. 2. The relationships between DT>0 and phytoplankton species richness and biomass were not linear but showed significant shifts, that is, richness suddenly doubled at DT>0=170days and phytoplankton biomass began to strongly increase at DT>0 around 220days. 3. The doubling in species richness corresponded to a change in the seasonal plankton succession from one to two peaks per year, and the shift in biomass corresponded to ashift in nutrient concentrations. 4. The geographical differences in richness and biomassshifts resulted in an exponential biodiversityecosystem functioning relationship along aDT>0 gradient. 5. We conclude that phytoplankton species richness and biomass are driven by different environmental factors, resulting in a nonlinear biodiversityecosystem functioning relationship. The shape of the diversityfunctioning relationship varies alongwith variations in environmental drivers, which is of highest importance for ongoing discussions about impacts of global change on biodiversity and ecosystem functioning.
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| 24. |
- Willen, Eva, et al.
(författare)
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Cyanotoxin production in seven Ethiopian Rift Valley lakes
- 2011
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Ingår i: Inland Waters. - 2044-2041 .- 2044-205X. ; 1:2, s. 81-91
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Tidskriftsartikel (refereegranskat)abstract
- We hypothesized that unusual deaths and illnesses in wild and domestic animals in lake areas of the Rift Valley south of Addis Ababa were caused by toxic cyanobacteria. In the first cyanotoxic analyses conducted in samples from Ethiopia, we found lakes Chamo, Abaya, Awassa, Chitu, Langano, Ziway, and Koka all had concentrations of microcystins (MC) ranging from trace to hazardous, whereas only traces less than limits of detection (LOD) of cylindrospermopsin (CYN) were found. In the December 2006 dry season we sampled the lakes for analyses of MC, CYN, species structures, and calculations of cyanobacteria biomass. We used the Utermol technique to analyse cyanobacterial biomass and monitored MC toxins using HPLC-DAD, LC-ESI-MS-MRM, and ELISA-test and CYN with HPLC-DAD and ELISA. The various toxicity tests coincided well. In 4 of the lakes (Chamo, Langano, Ziway, and Koka), the inter-lake range of total MC concentration was 1.3-48 mu g L-1; in 3 (Abaya, Awassa, and Chitu), we found only traces of MC. Microcystis aeruginosa was the dominant species, with Microcystis panniformis, Anabaena spiroides, and Cylindrospermopsis spp. as subdominants. The MC concentration, especially in Lake Koka, exceeded levels for serious health hazards for humans, cattle, and wildlife.
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| 25. |
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| 26. |
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| 27. |
- Willen, Eva
(författare)
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Regional species pools control community saturation in lake phytoplankton
- 2010
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Ingår i: Proceedings of the Royal Society B: Biological Sciences. - : The Royal Society. - 0962-8452 .- 1471-2954. ; 277, s. 3755-3764
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Tidskriftsartikel (refereegranskat)abstract
- Recent research has highlighted that positive biodiversity-ecosystem functioning relationships hold for all groups of organisms, including microbes. Yet, we still lack understanding regarding the drivers of microbial diversity, in particular, whether diversity of microbial communities is a matter of local factors, or whether metacommunities are of similar importance to what is known from higher organisms. Here, we explore the driving forces behind spatial variability in lake phytoplankton diversity in Fennoscandia. While phytoplankton biovolume is best predicted by local phosphorus concentrations, phytoplankton diversity (measured as genus richness, G) only showed weak correlations with local concentrations of total phosphorus. By estimating spatial averages of total phosphorus concentrations on various scales from an independent, spatially representative lake survey, we found that close to 70 per cent of the variability in local phytoplankton diversity can be explained by regionally averaged phosphorus concentrations on a scale between 100 and 400 km. Thus, the data strongly indicate the existence of metacommunities on this scale. Furthermore, we show a strong dependency between lake productivity and spatial community turnover. Thus, regional productivity affects beta-diversity by controlling spatial community turnover, resulting in scale-dependent productivity-diversity relationships. As an illustration of the interaction between local and regional processes in shaping microbial diversity, our results offer both empirical support and a plausible mechanism for the existence of common scaling rules in both the macrobial and the microbial worlds. We argue that awareness of regional species pools in phytoplankton and other unicellular organisms may critically improve our understanding of ecosystems and their susceptibility to anthropogenic stressors.
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| 28. |
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| 29. |
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| 30. |
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| 31. |
- Willen, R, et al.
(författare)
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Prospective malignancy grading, flow cytometry DNA-measurements and adjuvant chemotherapy for invasive squamous cell carcinoma of the uterine cervix
- 1993
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Ingår i: Anticancer research. - 1791-7530. ; 13:4, s. 1187-1196
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Tidskriftsartikel (refereegranskat)abstract
- In a prospective study comprising 310 consecutive patients with carcinoma of the cervix, FIGO stages I-IV, the prognostic significance of clinical and flow cytometric variable was evaluated in a univariate and multivariate analysis. The parameters studied included stage according to FIGO, age, histopathologic grade according to Ackerman and MGS scores, DNA ploidy, S-phase fraction as well as treatment with radiation only, surgery only or a combination thereof as well as adjuvant chemotherapy. Univariate analysis showed that patients in FIGO stages IA-IIA with MGS up to 14 points survived significantly better than other groups. MGS parameter mitosis, vascular invasion and type of invasion predicted survival as did clinical stage. Diploid cases with SPF > 15% survived less than remaining other cases. Multivariate analysis not including treatment indicated that FIGO stage and diploid cases with SPF > 15% predicted survival but not total MGS score and age. When treatment for FIGO stages IA-IIA was included, elderly women had a worse prognosis. Adjuvant chemotherapy, surgical alone or radiation alone did not demonstrate any differences within groups. In Figo stages IIB-IV, cases with radiotherapy only survived significantly better than patients with other treatment schedules. The frequency of low malignancy patients (< MGS 16) in relation to year of initial diagnosis was found to have decreased between years 1967 and 1988, probably as a result of screening activities.
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