| 1. |
- Birney, Ewan, et al.
(författare)
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Identification and analysis of functional elements in 1% of the human genome by the ENCODE pilot project
- 2007
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 447:7146, s. 799-816
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Tidskriftsartikel (refereegranskat)abstract
- We report the generation and analysis of functional data from multiple, diverse experiments performed on a targeted 1% of the human genome as part of the pilot phase of the ENCODE Project. These data have been further integrated and augmented by a number of evolutionary and computational analyses. Together, our results advance the collective knowledge about human genome function in several major areas. First, our studies provide convincing evidence that the genome is pervasively transcribed, such that the majority of its bases can be found in primary transcripts, including non-protein-coding transcripts, and those that extensively overlap one another. Second, systematic examination of transcriptional regulation has yielded new understanding about transcription start sites, including their relationship to specific regulatory sequences and features of chromatin accessibility and histone modification. Third, a more sophisticated view of chromatin structure has emerged, including its inter-relationship with DNA replication and transcriptional regulation. Finally, integration of these new sources of information, in particular with respect to mammalian evolution based on inter- and intra-species sequence comparisons, has yielded new mechanistic and evolutionary insights concerning the functional landscape of the human genome. Together, these studies are defining a path for pursuit of a more comprehensive characterization of human genome function.
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| 2. |
- Blennow Tullmar, Peter, et al.
(författare)
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Defect and electrical transport properties of Nb-doped SrTiO3
- 2008
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Ingår i: Solid State Ionics. - : Elsevier BV. - 0167-2738. ; 179:35-36, s. 2047-2058
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Tidskriftsartikel (refereegranskat)abstract
- This study reports the defect and electrical transport properties of Nb-doped SrTiO3, Samples with various A/B-ratios were synthesized by a modified glycine-nitrate combustion process and evaluated as a constituent in a SOFC anode. The phase purity and defect structure of the materials have been analyzed with SEM, XRD, TGA, and XANES. The electrical conductivity of Nb-doped strontium titanate (Sr0.94Ti0.9Nb0.1O3 - sintered in 9% H-2/N-2 at 1400 degrees C for 12 h) decreased with increasing temperature and showed a phonon scattering conduction mechanism with (sigma>120 S/cm at 1000 degrees C (in 9% H-2/N-2). The results were in agreement with the defect chemistry model of donor-doped SrTiO3 where the charge compensation changes from Sr vacancy compensation to the electronic type when samples are sintered in reducing atmosphere. XANES in combination with TGA indicated that Ti is the only species that is reduced to a lower oxidation state (from Ti4+ to Ti3+). The pre-edge fine structure (PEFS) from the XANES results indicated that Nb improved the overlap of the Ti atomic orbitals and thereby provided one more explanation for the positive effect of Nb on the electronic conductivity of Nb-doped SrTiO3. (C) 2008 Elsevier B.V. All rights reserved.
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| 3. |
- Blennow Tullmar, Peter, et al.
(författare)
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Effects of Sr/Ti-ratio in SrTiO3-based SOFC anodes investigated by the use of cone-shaped electrodes
- 2006
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Ingår i: Electrochimica Acta. - : Elsevier BV. - 0013-4686. ; 52:4, s. 1651-1661
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Tidskriftsartikel (refereegranskat)abstract
- In this work the A-site deficiency limit for undoped SrTiO3, calcined in air or reducing atmosphere, was investigated. XRD and SEM analyses showed that when using the solid-state synthesis route it was difficult to achieve any A-site deficiency. Even very small deviations from unity in the Sr/Ti-ratio resulted in impurity phases. The effects of Sr/Ti-ratio on the performance of SrTiO3 anodes for solid oxide fuel cells (SOFCs) was investigated by impedance spectroscopy with cone-shaped electrodes. The electrocatalytic activity of the SrTiO3 cone samples, with various amount of reduced titanium dioxide phases (Magnéli phases), was investigated for oxidation of H2 at 700 °C. High temperature treatment at 1000 °C, between the measurements at 700 °C, showed that high content of Magnéli phases leads to faster degradation of the activity. The suitability for using cone-shaped electrodes as a tool for investigating electrode materials is discussed.
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| 4. |
- Blennow Tullmar, Peter, et al.
(författare)
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Electrochemical characterization and redox behavior of Nb-doped SrTiO3
- 2009
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Ingår i: Solid State Ionics. - : Elsevier BV. - 0167-2738. ; 180:1, s. 63-63
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Tidskriftsartikel (refereegranskat)abstract
- Sr-vacancy compensated Nb-doped SrTiO3 with the nominal composition Sr0.94Ti0.9Nb0.1O3 has been evaluated as a solid oxide fuel cell (SOFC) anode material in terms of redox stability and electrochemical properties. Sr0.94Ti0.9Nb0.1O3 has been synthesized with a recently developed modified glycine-nitrate process. The phase purity and redox behavior have been analyzed with XRD and TGA. The electrochemical properties of Sr0.94Ti0.9Nb0.1O3 and a composite electrode of Sr0.94Ti0.9Nb0.1O3/YSZ have been investigated by electrochemical impedance spectroscopy (EIS) on cone shaped electrodes and on electrodes in a symmetrical cell configuration. The experiments indicated that the Nb-doped SrTiO3 electrodes were redox stable and showed a potential ability to be used as a part of a SOFC anode. The electrochemical activity appeared to be governed by the concentration of defect species (especially Ti3+ and V-0(++)) in the vicinity of the triple phase boundaries. However, the electrocatalytic activity of the materials was not sufficient and it needs to be improved if Nb-doped SrTiO3 based materials are to be realized as SOFC anodes. (C) 2008 Elsevier B.V. All rights reserved.
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| 5. |
- Blennow Tullmar, Peter, et al.
(författare)
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Niobium-doped strontium titanates as SOFC anodes
- 2008. - 4
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Ingår i: Advances in Solid Oxide Fuel Cells III. - 9780470196359 ; 28, s. 203-214
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Konferensbidrag (refereegranskat)abstract
- Sr-vacancy compensated Nb-doped SrTiO3 with the nominal composition Sr0.94Ti09Nb0.1O3 has been evaluated as part of a solid oxide fuel cell (SOFC) anode material in terms of redox stability, electrical conductivity, as well as electrochemical properties. Sr0.94Ti0.9Nb0.1O3 has been synthesized with a recently developed modified glycine-nitrate process. The synthesized powders have been calcined and sintered in air or in 9% H 2 / N2 between 800 - 1400 °C After calcination the samples were single phase Nb-doped strontium titanate with grain sizes of less than 100 nm in diameter on average. The phase purity, defect structure, and microstructure of the materials have been analyzed with SEM, XRD, and TGA. The electrical conductivity of the Nb-doped titanate decreased with increasing temperature and showed a phonon scattering conduction mechanism with σ > 120 S/cm at 1000 °C (in 9 % H2 / N2). The electrochemical properties of Sr0.94Ti0.9Nb 0.1O3 and a composite electrode of Sr 0.94Ti0.9Nb0.1O3/YSZ have been investigated by using a symmetrical cell configuration. The tests indicated that the electrodes were redox stable and showed a potential ability of the Nb-doped titanates to be used as a part of a SOFC anode. However, the catalytic activity of the materials was not sufficient and it needs to be improved if titanate based materials are to be realized as constituents in SOFC anodes.
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| 6. |
- Blennow Tullmar, Peter, et al.
(författare)
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Synthesis of Nb-doped SrTiO3 by a modified glycine-nitrate process
- 2007
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Ingår i: Journal of the European Ceramic Society. - : Elsevier BV. - 0955-2219. ; 27:13-15, s. 3609-3612
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Tidskriftsartikel (refereegranskat)abstract
- The objective of the present investigation was to develop a technique to synthesize submicronic particles of Nb-doped strontium titanate with a homogeneous composition. This was achieved by a modified glycine-nitrate process, using Ti-lactate, Nb-oxalate, and Sr(NO3)(2) as starting materials. A combination of both citric acid and glycine was needed in order to integrate the useful features of both complexation and combustion natures of citric acid and glycine, respectively. The amount of citric acid, glycine, and nitrates in the starting solution, as well as the source for extra nitrates, and the uniformity of heating during the thermal dehydration step were found to have significant influence on the final phase purity of the material. Calcination at 1100 degrees C in 7% H-2 in N-2 produced single phase Nb-doped strontium titanate with grain sizes of about 100 nm in diameter on average. (c) 2007 Elsevier Ltd. All rights reserved.
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| 7. |
- Elsik, Christine G., et al.
(författare)
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The Genome Sequence of Taurine Cattle : A Window to Ruminant Biology and Evolution
- 2009
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 324:5926, s. 522-528
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Tidskriftsartikel (refereegranskat)abstract
- To understand the biology and evolution of ruminants, the cattle genome was sequenced to about sevenfold coverage. The cattle genome contains a minimum of 22,000 genes, with a core set of 14,345 orthologs shared among seven mammalian species of which 1217 are absent or undetected in noneutherian (marsupial or monotreme) genomes. Cattle-specific evolutionary breakpoint regions in chromosomes have a higher density of segmental duplications, enrichment of repetitive elements, and species-specific variations in genes associated with lactation and immune responsiveness. Genes involved in metabolism are generally highly conserved, although five metabolic genes are deleted or extensively diverged from their human orthologs. The cattle genome sequence thus provides a resource for understanding mammalian evolution and accelerating livestock genetic improvement for milk and meat production.
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| 8. |
- Fouladiun, Marita, 1963, et al.
(författare)
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Body composition and time course changes in regional distribution of fat and lean tissue in unselected cancer patients on palliative care--correlations with food intake, metabolism, exercise capacity, and hormones
- 2005
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Ingår i: Cancer. - : Wiley. - 0008-543X .- 1097-0142. ; 103:10, s. 2189-98
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Several investigations that yielded different results in terms of net changes in body composition of weight-losing cancer patients have been reported that employed a variety of methods based on fundamentally different technology. Most of those reports were cross-sectional, whereas to the authors' knowledge there is sparse information available on longitudinal follow-up measurements in relation to other independent methods for the assessment of metabolism and performance. METHODS: For the current report, the authors evaluated time course changes in body composition (dual-energy X-ray absorptiometry) with measurements of whole body and regional distribution of fat and lean tissue in relation to food and dietary intake, host metabolism (indirect calorimetry), maximum exercise capacity (walking test), and circulating hormones in cancer patients who were receiving palliative care during 4-62 months of follow-up. The entire cohort comprised 311 patients, ages 68 years +/- 3 years who were diagnosed with solid gastrointestinal tumors (84 colorectal tumors, 74 pancreatic tumors, 73 upper gastrointestinal tumors, 51 liver-biliary tumors, 3 breast tumors, 5 melanomas, and 21 other tumor types). RESULTS: Decreased body weight was explained by loss of body fat, preferentially from the trunk, followed by leg tissue and arm tissue, respectively. Lean tissue (fat-free mass) was lost from arm tissue, whereas trunk and leg tissue compartments increased, all concomitant with declines in serum albumin, increased systemic inflammation (C-reactive protein, erythrocyte sedimentation rate), increased serum insulin, and elevated daily caloric intake; whereas serum insulin-like growth factor 1 (IGF-1), resting energy expenditure, and maximum exercise capacity remained unchanged in the same patients. Serum albumin levels (P < 0.001), whole body fat (P < 0.02), and caloric intake (P < 0.001) predicted survival, whereas lean tissue mass did not. Daily intake of fat and carbohydrate was more important for predicting survival than protein intake. Survival also was predicted by serum IGF-1, insulin, leptin, and ghrelin levels (P < 0.02 - P < 0.001). Serum insulin, leptin, and ghrelin (total) levels predicted body fat (P < 0.001), whereas IGF-1 and thyroid hormone levels (T3, free T3) predicted lean tissue mass (P < 0.01). Systemic inflammation primarily explained variation in lean tissue and secondarily explained loss in body fat. Depletion of lean arm tissue was related most to short survival compared with the depletion of lean leg and trunk tissue. CONCLUSIONS: The current results demonstrated that body fat was lost more rapidly than lean tissue in progressive cancer cachexia, a phenomenon that was related highly to alterations in the levels of circulating classic hormones and food intake, including both caloric amount and diet composition. The results showed importance in the planning of efficient palliative treatment for cancer patients.
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| 9. |
- Gereke, Thomas, et al.
(författare)
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Experimental and numerical determination of the hygroscopic warping of cross-laminated solid wood panels
- 2009
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Ingår i: Holzforschung. - 1437-434X. ; 63:3, s. 340-347
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Tidskriftsartikel (refereegranskat)abstract
- The moisture-induced warping of three-layered cross-laminated solid wood panels made of Norway spruce was studied. The panels were exposed to different climate conditions at 65% and 100% relative humidity at the two panel faces. The results showed increasing cup deformation with an increasing relative thickness of the outer layers. The annual growth ring orientation was found to have a significant influence on the magnitude of the cup deformation. Measurements and numerical simulations of the moisture distribution within the panel were made in order to provide data for numerical simulations of the warping. A distinctive moisture profile with a conspicuous influence of the adhesive bond lines was found. The coefficient of diffusion of the adhesive bond lines was determined from the measurements and simulations. The mechanical material model used for the warping simulations takes into account elastic strain, moisture-induced swelling, and mechano-sorptive strain. The simulations showed good agreement with the warping test results. The most important material parameters for the cup deformation, which were identified in a parametric study of a panel with vertically oriented annual rings, are the moduli of elasticity and the swelling coefficients in the longitudinal and radial direction. Furthermore, the mechano-sorptive coefficient in radial direction was found to have a significant influence on warp.
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| 10. |
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| 11. |
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| 12. |
- Jimenez, Camilo, et al.
(författare)
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Follow-up of pituitary tumor volume in patients with acromegaly treated with pegvisomant in clinical trials
- 2008
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Ingår i: European Journal of Endocrinology. - 1479-683X. ; 159:5, s. 517-523
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Tidskriftsartikel (refereegranskat)abstract
- Objective: We examined pituitary tumor volumes in patients treated with pegvisomant for 18 months or longer and in whom the tumors were monitored for at least 3 years. We present details on 9 of 304 patients in clinical trials with pegvisomant who experienced tumor growth within the first year of treatment. Method: Magnetic reonance images prior to start of pegvisomant and at last follow-up were examined in 43 patients (14% of participating patients). Twenty-nine had received prior radiation therapy (18% of irradiated patients and all but live received somatostatin analogs between periods of pegvisomant treatment. Results: At follow-up, the received tumor volume was 0.6 cc (range 0.0-19.7 ccl. in comparison with 1.6 cc (0.0-19.7 cc) at baseline (P<0.001). Twenty-five patients, of which 23 received radiation therapy, had tumor volume reduction therapy, had an increase in tumor volume from 1.61 to 1.93 cc. Of the nine patients with tumor growth, six had progressive growth before initiating pegvisomant. Two patients with stable tumors while on octreotide experienced enlargement after octreotide discontinuation but remained stable on long-term pegvisomant therapy. Conclusion: The present data indicate that pegvisomant does not promote tumor growth and suggest that the nine observed cases of tumor progression. which occured within 8 months after commencing pegvisomant, are likely rebound expansions after discontinuation of somatostatin analogs and/or the natural history of aggressively growing pituitary tumors. Continued long-term surveillance of tumor volume, particularly in non-irradiated patients is recommended.
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| 13. |
- Konradsson, Asa, et al.
(författare)
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Inhibition of the glycine transporter GlyT-1 potentiates the effect of risperidone, but not clozapine, on glutamatergic transmission in the rat medial prefrontal cortex.
- 2006
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Ingår i: Synapse. - : Wiley. - 0887-4476 .- 1098-2396. ; 81, s. 104-104
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Tidskriftsartikel (refereegranskat)abstract
- Clinical studies suggest that the efficacy of the atypical antipsychotic drug (APD) risperidone (but not clozapine) can be augmented by adjunctive treatment with agonists at the glycine site of the N-methyl-D-aspartate (NMDA) receptor. By using intracellular recording, we have investigated the effect of the glycine transporter-1 (GlyT-1) inhibitor N [3-(4'-fluorophenyl)-3-(4'phenylphenylphenoxy) propyl] sarcosine (NFPS) on NMDA-induced currents in pyramidal cells of the medial prefrontal cortex (mPFC), both when given alone and in combination with either risperidone or clozapine. Both risperidone and clozapine enhanced the NMDA-induced currents. The concentration-response curves were biphasic, and the maximal effect of clozapine on the NMDA-induced currents was significantly larger than the maximal effect of risperidone. NFPS also significantly potentiated the NMDA-induced currents, when given alone. Moreover, NFPS (1 microM) augmented the effect of both the maximal (20 nM), and a submaximal (10 nM), concentration of risperidone. In contrast, NFPS did not potentiate either the effect of the maximal (100 nM) or a submaximal (80 nM) concentration of clozapine on the NMDA-induced currents. These data may explain the beneficial clinical results of using glycine reuptake antagonists as adjuvant treatment to risperidone. Our findings also suggest that risperidone and clozapine may affect NMDA receptor-mediated neurotransmission differently in the mPFC.
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| 14. |
- Lönnroth, Christina, 1946, et al.
(författare)
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Survival and erythropoietin receptor protein in tumours from patients randomly treated with rhEPO for palliative care.
- 2008
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Ingår i: Medical oncology (Northwood, London, England). - : Springer Science and Business Media LLC. - 1357-0560 .- 1559-131X. ; 25:1, s. 22-9
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Recombinant erythropoietin (rhEPOalpha) corrects anaemia, improves physical functioning and quality of life in cancer patients. However, published reports have suggested risks for tumour stimulation by provision EPO to patients with remaining tumour cells perhaps related to the presence of EPO receptor protein in tumour tissue. Therefore, the aim of the present study was to exclude a possibility that cancer patients who respond favourably to EPO treatment have mainly tumours with low EPO receptor protein expression. METHODS: Tumour tissue was evaluated in 87 patients out of 108 randomly allocated for treatment with rhEPOalpha (n = 50) versus controls (n = 58). Tumour cell proliferation (Ki-67 index) and EPO receptor protein expression were evaluated by immunohistochemistry. RESULTS: EPO treatment varied between 2 and 35 months, in doses between 10,000 and 40,000 Units/week. Ki-67 index did not differ between study and control patients before EPO treatment. Tumour tissue erythropoietin receptor protein was also similar between treated and untreated patients. Around 40% of tumour cells contained EPO receptors. Survival did not differ among EPO treated and control patients analysed as intention to treat, while survival was significantly improved in EPO treated patients per protocol treatment (P < 0.05). Ki-67 index and tumour tissue erythropoietin receptor protein did not predict survival, which systemic inflammation (ESR) did (P < 0.02). CONCLUSIONS: Our results support that reported risk to accelerate disease progression by EPO treatment in palliative care is not justified in patients with solid, gastrointestinal cancer despite tumour presence of EPO receptor protein.
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| 15. |
- Margulies, Elliott H, et al.
(författare)
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Analyses of deep mammalian sequence alignments and constraint predictions for 1% of the human genome
- 2007
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Ingår i: Genome Research. - : Cold Spring Harbor Laboratory. - 1088-9051 .- 1549-5469. ; 17:6, s. 760-774
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Tidskriftsartikel (refereegranskat)abstract
- A key component of the ongoing ENCODE project involves rigorous comparative sequence analyses for the initially targeted 1% of the human genome. Here, we present orthologous sequence generation, alignment, and evolutionary constraint analyses of 23 mammalian species for all ENCODE targets. Alignments were generated using four different methods; comparisons of these methods reveal large-scale consistency but substantial differences in terms of small genomic rearrangements, sensitivity (sequence coverage), and specificity (alignment accuracy). We describe the quantitative and qualitative trade-offs concomitant with alignment method choice and the levels of technical error that need to be accounted for in applications that require multisequence alignments. Using the generated alignments, we identified constrained regions using three different methods. While the different constraint-detecting methods are in general agreement, there are important discrepancies relating to both the underlying alignments and the specific algorithms. However, by integrating the results across the alignments and constraint-detecting methods, we produced constraint annotations that were found to be robust based on multiple independent measures. Analyses of these annotations illustrate that most classes of experimentally annotated functional elements are enriched for constrained sequences; however, large portions of each class (with the exception of protein-coding sequences) do not overlap constrained regions. The latter elements might not be under primary sequence constraint, might not be constrained across all mammals, or might have expendable molecular functions. Conversely, 40% of the constrained sequences do not overlap any of the functional elements that have been experimentally identified. Together, these findings demonstrate and quantify how many genomic functional elements await basic molecular characterization.
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| 16. |
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| 17. |
- Osterman, Jesper, 1971-
(författare)
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Investigations of Optical Properties and Photo-Alignment in Bistable Nematic Liquid Crystal Displays
- 2005
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In recent years portable electronic devices, such as mobile phones and personal digital assistants, have increased the demand for high performance displays with low power consumption. An interesting candidate with the potential of fulfilling these demands is the reflective single-polarizer surface controlled bistable twisted nematic liquid crystal display. The main focus of this work involves the optical properties of displays based on these bistable structures. In the investigations, the display is considered as an integrated optical system, containing not only the liquid crystal cell, but also components such as polarizers and retardation films. The specific aim of the thesis was to derive new optical modes of the reflective single-polarizer bistable twisted nematic device using the Jones matrix method to study the interaction between the polarization of light and the optically anisotropic media. The electro-optical properties of the derived modes have been studied and evaluated both theoretically and experimentally. The modes possess excellent brightness and high contrast ratio. By introducing a quarter-wave retardation film into the optical configuration, the contrast ratio can be significantly increased by preventing spectral leakage of light in the dark state. To experimentally realize the derived optical modes, special layers for the alignment of the liquid crystal molecules on the cell substrate surface have been proved needed. Therefore, also the photo-alignment technology of nematic liquid crystals on novel alignment materials has been studied with the aim to control liquid crystal cell parameters such as pretilt angle and anchoring energy, both critical for the bistable switching. The results of this thesis will increase the understanding of the optical properties of the reflective single-polarizer bistable twisted nematic liquid crystal display and will be valuable when considering this type of device for practical applications.
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| 18. |
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| 19. |
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| 20. |
- Thunberg, Per, 1968-, et al.
(författare)
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Estimation of ejection fraction and stroke volume using single- and biplane magnetic resonance imaging of the left cardiac ventricle
- 2008
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Ingår i: Acta Radiologica. - London : Taylor & Francis. - 0284-1851 .- 1600-0455. ; 49:9, s. 1016-1023
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Background: In cardiac magnetic resonance imaging (MRI), left ventricular stroke volume (SV) and ejection fractions (EF) are occasionally calculated using single-plane and biplane ellipsoid models. In previous studies, the calculated SV and EF using single- and biplane ellipsoid models have been compared to reference values calculated from short-axis (SA) images. In these studies, however, it has been emphasized that through-plane motion of the basal SA images represents an important source of error, which may result in incorrect reference values.Purpose: To compare the calculated SV and EF using single-plane and biplane ellipsoid models with SV and EF calculated from SA images in which compensation was made for through-plane motion.Material and Methods: A group of 20 patients who underwent MRI examination were included in the study. SV and EF were calculated using the stack of SA images (which had been compensated for through-plane motion) and compared to the SV and EF calculated according to the single- and biplane ellipsoid models.Results: The mean difference between the single-plane model and the reference was -0.3±6.5 for EF and 7.2±17.1 ml for SV. Corresponding comparison between the biplane method and the reference resulted in a mean difference of 0.3±6.1 for EF and 11.8±14.9 ml for SV.Conclusion: The results from this study show that left ventricular EF can be adequately estimated using the single- and biplane ellipsoid models, while SV tends to be overestimated using both geometrical models
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| 21. |
- Thunberg, Per, 1968-, et al.
(författare)
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Separating the left cardiac ventricle from the atrium in short axis MR images using the equation of the atrioventricular plane
- 2008
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Ingår i: Clinical Physiology and Functional Imaging. - Oxford : Wiley-Blackwell Publishing Inc.. - 1475-0961 .- 1475-097X. ; 28:4, s. 222-228
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Tidskriftsartikel (refereegranskat)abstract
- Short axis (SA) images obtained from cardiac magnetic resonance imaging are used to advantage in the calculation of important clinical parameters such as the ejection fraction and stroke volume (SV). A prerequisite for these calculations is the separation of the left ventricle and the left atrium. When only using the information seen in the SA images this separation can be a source of error due to the through-plane motion of the basal part of the left ventricle. In this study a method is proposed where the separation of the left ventricle and the atrium is performed by identifying the intersections of the atrioventricular plane in the SA images. The equation of the atrioventricular plane was determined in both systole and diastole using long axis and four chamber image views. Stroke volumes were measured in 20 patients using SA images where the endocardium had been delineated. The SV obtained using the new method was compared with quantitative flow measurements and the conventional technique for calculation of SV from SA images, respectively. The agreement of SV was, according to Bland-Altman analysis, 2.0 ml (95% CI -12.0 to 15.9 ml) in comparison with the flow measurements and 2.2 ml (95% CI -9.2 to 13.6 ml) compared to the conventional method. Inter- and intra-observer variability, when using the new proposed method, was small. This study shows that the identification of the left atrioventricular plane in SA images can be used in the separation of the left atrium and ventricle.
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