| 1. |
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| 2. |
- Aad, G., et al.
(författare)
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Determination of the strong coupling constant from transverse energy-energy correlations in multijet events at √ s=13 TeV with the ATLAS detector
- 2023
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Ingår i: Journal of High Energy Physics (JHEP). - : Springer Nature. - 1126-6708 .- 1029-8479. ; 2023:7
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Tidskriftsartikel (refereegranskat)abstract
- Measurements of transverse energy-energy correlations and their associated azimuthal asymmetries in multijet events are presented. The analysis is performed using a data sample corresponding to 139 fb-1 of proton-proton collisions at a centre-of-mass energy of root s = 13TeV, collected with the ATLAS detector at the Large Hadron Collider. The measurements are presented in bins of the scalar sum of the transverse momenta of the two leading jets and unfolded to particle level. They are then compared to next-to-next-to-leading-order perturbative QCD calculations for the first time, which feature a significant reduction in the theoretical uncertainties estimated using variations of the renormalisation and factorisation scales. The agreement between data and theory is good, thus providing a precision test of QCD at large momentum transfers Q. The strong coupling constant alpha(s) is extracted as a function of Q, showing a good agreement with the renormalisation group equation and with previous analyses. A simultaneous fit to all transverse energy-energy correlation distributions across different kinematic regions yields a value of alpha(s)( mZ) = 0.1175 +/- 0.0006 (exp.)(+0.0034) (-0.0017) (theo.), while the global fit to the asymmetry distributions yields alpha(s)(m(Z)) = 0.1185 +/- 0.0009 (exp.)(+0.0025)(-0.0012)(theo.).
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| 3. |
- Arne, Gabriella, et al.
(författare)
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Expression profiling of GIST: CD133 is associated with KIT exon 11 mutations, gastric location, and poor prognosis.
- 2011
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Ingår i: International journal of cancer. Journal international du cancer. - : Wiley. - 1097-0215 .- 0020-7136. ; 129:5, s. 1149-1161
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Tidskriftsartikel (refereegranskat)abstract
- In gastrointestinal stromal tumors (GISTs), KIT exon 11 deletions are associated with poor prognosis. The aim of this study was to determine the gene expression profiles of GISTs carrying KIT exon 11 deletions and to identify genes associated with poor prognosis. Expression profiling was performed on 9 tumors with KIT exon 11 deletions and 7 without KIT exon 11 mutations using oligonucleotide microarrays. In addition, gene expression profiles for 35 GISTs were analyzed by meta-analysis. Expression of CD133 (prominin-1) protein was examined by tissue microarray (TMA) analysis of 204 GISTs from a population-based study in western Sweden. Survival analysis was performed on patients subjected to R0 resection (n=180) using the Cox proportional hazards model. Gene expression profiling, meta-analysis, and qPCR showed up regulation of CD133 in GISTs carrying KIT exon 11 deletions. Immunohistochemical analysis on TMA confirmed CD133 expression in 28% of all tumors. CD133 positivity was more frequent in gastric GISTs (48%) than in small intestinal GISTs (4%). CD133 positivity was also more frequent in GISTs with KIT exon 11 mutations (41%) than in tumors with mutations in KIT exon 9, PDGFRA, or wild-type tumors (0-17%). Univariate survival analysis showed a significant correlation between the presence of CD133 protein and shorter overall survival (hazard ratio=2.23, P=0.027). Multivariate analysis showed that CD133 provided additional information on patient survival compared to age, sex, NIH risk group and mutational status. CD133 is expressed in a subset of predominantly gastric GISTs with KIT exon 11 mutations and poor prognosis.
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| 4. |
- Arne, Gabriella, et al.
(författare)
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Gastrointestinal stromal tumors (GISTs) express somatostatin receptors and bind radiolabeled somatostatin analogs.
- 2013
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Ingår i: Acta oncologica (Stockholm, Sweden). - 1651-226X .- 0284-186X. ; 52:4, s. 783-792
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Tidskriftsartikel (refereegranskat)abstract
- Background. Gastrointestinal stromal tumors (GISTs) can be effectively treated with tyrosine kinase inhibitors (TKIs). However, some patients with GIST develop drug resistance, and alternative treatment strategies are therefore needed. The aim of this study was to analyze the expression of somatostatin receptors (SSTR) in GIST as a target for peptide receptor-mediated radiotherapy (PRRT). Material and methods. Expression profiling of SSTR1-5 was performed on biopsies from 34 GISTs (16 gastric tumors, 15 small intestinal tumors, and three rectal tumors). SSTR scintigraphy ((111)In-octreotide) and measurement of (111)In activity in tumor specimens was performed in seven patients. Uptake and internalization of (177)Lu- octreotate was studied in primary cell cultures from two patients. Results. Quantitative PCR analysis showed expression of SSTR1 and SSTR2 in the majority of tumors, while SSTR3-5 were expressed at low levels. Immunohistochemical analysis confirmed the presence of SSTR1 and SSTR2 proteins in all GISTs, and SSTR3-5 in a subset of tumors. Diagnostic imaging by SSTR scintigraphy, using (111)In-octreotide, demonstrated tumor uptake of (111)In in three of six GIST patients. Measurement of (111)In activity in excised tumor specimens from five patients gave tumor-to-blood (T/B) activity ratios of between eight and 96. Tumor cells in primary culture (gastric and small intestinal GIST) specifically bound and internalized (177)Lu when incubated with the therapeutic compound (177)Lu-octreotate for 4-48 hours (p < 0.05). Conclusion. Peptide receptor-mediated radiotherapy via SSTR may provide a novel treatment strategy in carefully selected GIST patients with TKI-resistant tumors.
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| 5. |
- Bjursell, Cecilia, 1971, et al.
(författare)
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PMM2 mutation spectrum, including 10 novel mutations, in a large CDG type 1A family material with a focus on Scandinavian families.
- 2000
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Ingår i: Human mutation. - 1098-1004 .- 1059-7794. ; 16:5, s. 395-400
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Tidskriftsartikel (refereegranskat)abstract
- Carbohydrate-deficient glycoprotein syndrome type IA (CDG IA) is an autosomal recessive disease characterized clinically by severe involvement of the central and peripheral nervous system, and biochemically by complex defects in carbohydrate residues in a number of serum glycoproteins. CDG IA is caused by mutations in the PMM2 gene located in chromosome region 16p13. In this study, 61 CDG type IA patients (122 chromosomes) were screened for mutations in the PMM2 gene using a combination of SSCP and sequence analysis. More than 95% of the mutations could be detected. All of them were missense mutations. Mutations 422G>A and 357C>A were strikingly more common in the material and comprised 58% of mutations detected. Of the 20 mutations found, 10 were not reported previously. Seven mutations, e.g. 26G>A (five alleles) and 548T>C (seven alleles), were found only in Scandinavian families. The most common genotype was 357C>A/422G>A (36%). Three patients were homozygous, 357C>A/357C>A (two cases), and 548T>C/548T>C (one case). No patients homozygous for the most common mutation 422G>A were detected. The different mutations were clustered e.g., in that most were located in exon 5 (five) and exon 8 (six), while no mutation was detected in exon 2. When the frequencies of each mutation were included, exon 5 comprised 61% (65 chromosomes) of the mutations; in Scandinavian patients the frequency of these mutations was 72%. Thus, analysis of exon five in these patients enables both reliable and time-saving first screening in prenatal diagnostic cases. This could be followed by a second step of additional strategies for the detection of other mutations.
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| 6. |
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| 7. |
- Gudjonsdottir, Audur, 1959, et al.
(författare)
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The risk of celiac disease in 107 families with at least two affected siblings.
- 2004
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Ingår i: Journal of pediatric gastroenterology and nutrition. - 0277-2116 .- 1536-4801. ; 38:3, s. 338-42
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: Screening for celiac disease (CD) in the apparently healthy members of 107 nuclear families with two affected siblings (sib pair) and estimating the risk of CD in siblings and parents. METHODS: One hundred seven families from Sweden and southern Norway with at least two affected children were investigated. Frozen sera from 187 of the 192 healthy parents and from 94 of 95 siblings without diagnosed CD were examined for total immunoglobulin A (IgA) and anti-endomysial antibodies (EMA). Individuals with positive antibody titers underwent small intestinal biopsy. RESULTS: Positive test for EMA was found in 6 of 94 (6.3%) siblings without previously diagnosed CD and in 8 of 189 (4.2%) parents. CD was confirmed by small intestinal biopsy in all siblings and seven parents. The estimated risk for CD in multiply affected families was 26.3% for siblings and 12.9% for parents. An unexpected male preponderance was found among the new CD cases (10 males, 3 females). CONCLUSION: The risk of CD in the members of nuclear families with two affected children is approximately three times higher than that when only one child is affected. The high male preponderance of new cases is unexpected and could not be explained fully by more silent disease in males as compared with females. Considering the high level of knowledge about CD in these families, the number of undiagnosed cases is surprisingly high. The authors suggest that serologic screening should be offered to all first-degree relatives of patients with CD.
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| 8. |
- Gustavsson, Johan, 1974, et al.
(författare)
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High-speed 850-nm VCSELs for 40 Gb/s transmission
- 2010
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- We have explored the possibility to extend the data transmission rate for standard 850-nm GaAs-based VCSELs beyond the 10 Gbit/s limit of today's commercially available directly-modulated devices. By sophisticated tailoring of the design for high-speed performance we demonstrate that 10 Gb/s is far from the upper limit. For example, the thermal conductivity of the bottom mirror is improved by the use of binary compounds, and the electrical parasitics are kept at a minimum by incorporating a large diameter double layered oxide aperture in the design. We also show that the intrinsic high speed performance is significantly improved by replacing the traditional GaAs QWs with strained InGaAs QWs in the active region. The best overall performance is achieved for a device with a 9 μm diameter oxide aperture, having in a threshold current of 0.6 mA, a maximum output power of 9 mW, a thermal resistance of 1.9 °C/mW, and a differential resistance of 80 Ω. The measured 3dB bandwidth exceeds 20 GHz, and we experimentally demonstrate that the device is capable of error-free transmission (BER
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| 9. |
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| 10. |
- Hyde, Kevin D., et al.
(författare)
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Incorporating molecular data in fungal systematics: a guide for aspiring researchers
- 2013
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Ingår i: Current Research in Environmental and Applied Mycology. - : Mushroom Research Foundation. - 2229-2225. ; 3:1
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Tidskriftsartikel (refereegranskat)abstract
- The last twenty years have witnessed molecular data emerge as a primary research instrument in most branches of mycology. Fungal systematics, taxonomy, and ecology have all seen tremendous progress and have undergone rapid, far-reaching changes as disciplines in the wake of continual improvement in DNA sequencing technology. A taxonomic study that draws from molecular data involves a long series of steps, ranging from taxon sampling through the various laboratory procedures and data analysis to the publication process. All steps are important and influence the results and the way they are perceived by the scientific community. The present paper provides a reflective overview of all major steps in such a project with the purpose to assist research students about to begin their first study using DNA-based methods. We also take the opportunity to discuss the role of taxonomy in biology and the life sciences in general in the light of molecular data. While the best way to learn molecular methods is to work side by side with someone experienced, we hope that the present paper will serve to lower the learning threshold for the reader.
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| 11. |
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| 12. |
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| 13. |
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| 14. |
- Kristiansson, Birgitta, 1942, et al.
(författare)
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Evaluation and simple tuning of PID controllers with high-frequency robustness
- 2006
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Ingår i: Journal of Process Control. ; 16:2, s. 91-102
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Tidskriftsartikel (refereegranskat)abstract
- An extensive study of robust and optimal tuning of PID controllers for stable non-oscillating plants is presented. It is built on a set of well defined criteria related to output performance,stability margins and control activity. Different interesting properties of the closed loop systems are observed. A set of simple tuning rules is based on these observations. These rules are compared to a couple of well established tuning methods and are shown to give well competitive results, especially when simplicity, low control activity and high-frequency robustness are emphasized. Derivative action is shown to improve performancesignificantly compared to PI control, with equal stability margin and a moderate increase of control activity, for most plants, including those with significant time delay.
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| 15. |
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| 18. |
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| 19. |
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| 20. |
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| 21. |
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| 22. |
- Kristiansson, J., et al.
(författare)
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Prolonged vasopressor support during hip-fracture surgery is a risk factor for enhanced mortality
- 2019
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Ingår i: Acta Anaesthesiologica Scandinavica. - : Wiley. - 0001-5172. ; 63:1, s. 46-54
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Tidskriftsartikel (refereegranskat)abstract
- Background Hip fracture is a common injury in the elderly population and is associated with high morbidity and mortality. Intraoperative hypotension is commonly noted, and is often treated with vasopressors (VP), however, to what extent is unknown. We set out to examine retrospectively how many hip fracture-patients received VP perioperatively and further to investigate if VP treatment is connected to increased mortality. Method Data on VP treatment were captured from medical and anaesthesia journals, and if so, data were investigated to find potential confounders. Patients were divided into (a) no VP, (b) VP by injection, (c) VP by infusion <3 hours, and (d) VP by infusion >= 3 hours to achieve stratification. Results Nine hundred and ninety-seven patients were included. About 80.4% received VP treatment. The 30-day mortality rates in subgroups were 3.6%, 5.4%, 6.4% and 19.1% respectively. The 90-day mortality rates were 6.7%, 10.3%, 11.6% and 30.3% respectively. Finally, the same patient groups had 365-day mortality rates of 12.8%, 20.0%, 23.3% and 44.9% respectively. We found a significant increase in mortality (30-90-365 days) in patients receiving VP infusion >= 3 hours, after adjusting for confounding factors. There was no increased mortality in patients treated by injection and by infusion Conclusion Vasopressor treatment is common during hip fracture surgery. Patients treated with VP infusion >= 3 hours have increased mortality, while patients treated with injections or infusion
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| 23. |
- Kristiansson, Johan, et al.
(författare)
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The influence of time-to-surgery on mortality after a hip fracture
- 2020
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Ingår i: Acta Anaesthesiologica Scandinavica. - : Wiley. - 0001-5172 .- 1399-6576. ; 64:3, s. 347-353
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Tidskriftsartikel (refereegranskat)abstract
- Background The effect of time-to-surgery on mortality in acute hip fracture (AHF) patients has been debated and studies are inconsistent regarding from what time limit mortality starts to increase. At Sahlgrenska University Hospital/Molndal, surgery is recommended within 24 hours leaving little time for pre-operative optimization. However, internationally the definition of early surgery varies between 24 and 48 hours and over. This retrospective study was initiated to investigate the relation between time-to-surgery and 30-day mortality. Method Data of AHF patients from January 2007 through December 2016 were collected. The variables analysed were: age, gender, American Society of Anesthesiologists physical status classification, surgical method (prosthesis or osteosynthesis) and time-to-surgery, along with 30-day mortality. Primary outcome was 30-day mortality related to time-to-surgery divided into groups. Secondary outcome was 30-day mortality related to time-to-surgery analysed hour-by-hour. Results From 10,844 eligible patients, 9,270 patients were included into the study. Mean time-to-surgery was 19.4 hours and overall 30-day mortality was 7.6%. Adjusted Cox regression analysis revealed an increased mortality rate in patients with time-to-surgery >48 hours. In the hour-by-hour analysis, significant mortality increase was observed at 39 hours of time-to-surgery. Patients with time-to-surgery >24 hours did not have increased mortality compared to patients with time-to-surgery In AHF patients, a time-to-surgery exceeding 39-48 hours was associated with increased mortality. Patients with surgeries performed before 39-48 hours did not have increased mortality and this time may, in some patients, be used for optimization prior surgery even if time-to-surgery exceeds 24 hours.
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| 24. |
- Kristiansson, Per, et al.
(författare)
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Heredity of pregnancy-related pelvic girdle pain in Sweden
- 2023
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Ingår i: Acta Obstetricia et Gynecologica Scandinavica. - : John Wiley & Sons. - 0001-6349 .- 1600-0412. ; 102:10, s. 1250-1258
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Pelvic girdle pain during and after pregnancy is a major public health problem with significant daily problems for affected women and their families. There is now accumulating evidence that pregnancy-related pelvic girdle pain originates from the sacroiliac joints and the pubic symphysis as well as their extra-articular ligaments. However, the heritability of the disease remains to be determined. We hypothesized that there is an increased familial risk of pregnancy-related pelvic girdle pain. Material and methods: A population-based national database linkage registry study of approximately 9.3 million individuals within 4.2 million families in Sweden with a recruitment period from 1997 to 2018. The Swedish Multi-generation register was used to find female pairs of twins, full siblings, half-siblings and first cousins where both in the pairs had a completed pregnancy. The outcome measure was diagnosis of pregnancy-related pelvic girdle pain (International Classification of Diseases-10 O26.7 [1997–2018]) in the first pregnancy. Data was obtained from the Swedish Hospital Discharge Register, the Swedish Outpatient Care Register, the Swedish Medical Birth Register, the Primary Healthcare Register, and Medical Treatment Register. Cox regression analysis was used to calculate adjusted estimated effect of the exposure variable familial history of pregnancy-related pelvic girdle pain on the outcome variable pregnancy-related pelvic girdle pain at first birth. Results: From the registers, 1 010 064 women pregnant with their first child within 795 654 families were collected. In total, 109 147 women were diagnosed with pregnancy-related pelvic girdle pain. The adjusted hazard ratio for a familial risk of pregnancy-related pelvic girdle pain was 2.09 (95% CI 1.85–2.37) among twins (monozygotic and dizygotic), 1.78 (95% CI 1.74–1.82) in full siblings, 1.16 (95% CI 1.06–1.28) in half-siblings from the mother, 1.09 (95% CI 1.024–1.16) in half-siblings from the father and 1.09 (95% CI 1.07–1.12) in first cousins. Conclusions: This nationwide observational study showed a familial clustering of pregnancy-related pelvic girdle pain. The hazard ratio for the condition was associated with the degree of relatedness, suggesting that heredity factors contribute to the development of pregnancy-related pelvic girdle pain. There is no causal treatment available for pregnancy-related pelvic girdle pain and further studies are now encouraged to clarify the specific genetic factors that contribute to the disease and for future targeted interventions.
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| 25. |
- Kristiansson, Per, et al.
(författare)
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Photon-tagged nuclear reaction analysis for trace element determination
- 1997
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Ingår i: Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 132:1, s. 159-176
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Tidskriftsartikel (refereegranskat)abstract
- The new trace element measurement technique "photon-tagged Nuclear Reaction Analysis" (pNRA) is introduced and the experimental procedures are described in detail. The pNRA-technique is an ion-beam analytical technique intended for the determination of the abundance of the lightest elements, ranging from lithium to phosphorus. The technique is a complement to the PIXE technique. pNRA is a multiparameter technique, using fast coincidence criteria and high time resolution which identifies and measures the products of nuclear reactions from which the amount of an element in the irradiated target can be determined. A detection system suitable for use in pNRA analysis is described. Different aspects of experimental parameters, e.g. time resolution and γ-efficiency, are discussed and evaluated. Yield curves for all relevant light isotopes are presented for a proton beam energy between 3.5 and 3.75 MeV, and minimum detection limits (MDLs) are extracted for different environments. The results of the MDL measurements with pNRA_ are compared with the detection limits of other frequently used techniques such as proton-induced γ-emission (PIGE) and particle elastic scattering analysis (PESA), and are shown to match these other techniques very well.
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| 26. |
- Larker, Richard, et al.
(författare)
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Heat treatments of the low-expansion superalloy Incoloy 909 for application in ceramic/metal joints and in metal matrix composites
- 1992
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Ingår i: Materials & design. - : Elsevier. - 0264-1275 .- 1873-4197. ; 13:1, s. 11-15
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Tidskriftsartikel (refereegranskat)abstract
- Increasing efficiency demands on gas turbines have promoted the development of superalloys with low thermal expansion up to intermediate temperatures, to reduce the need of cooling for preservation of efficient clearances between rotating and stationary parts. These materials are also of prime interest for joins to engineering ceramics such as silicon nitride and silicon carbide, and as a matrix with W or SiC fibres in metal matrix composites (MMC). The paper deals with the thermomechanical and microstructural stability of Incology 909 during possible joining and densification treatments. Thermal expansion behaviour and joining/densification temperatures suitable for retaining the desired structure of the superalloy are presented.
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| 27. |
- Lennartson, Bengt, 1956, et al.
(författare)
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Evaluation and tuning of robust PID controllers
- 2009
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Ingår i: IET Control Theory and Applications. - : Institution of Engineering and Technology (IET). - 1751-8644 .- 1751-8652. ; 3:3, s. 294-302
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Tidskriftsartikel (refereegranskat)abstract
- Based on a general controller evaluation method, taking both performance and robustness in different frequency regions into account, an analytical PID design method is presented. It is related to the well known and often used lambda tuning approach, which is based on internal model control (IMC) for a specific second-order non-minimum phase plant model. The analytical method introduced in this paper includes two tuning parameters, one that guarantees a specified stability margin for the given model, and one that is also able to adjust the control activity to a desired level. The suggested method, called robust IMC, gives the user the important freedom to control both mid- and high-frequency robustness. An extended evaluation procedure also illustrates how efficiently PI and PID controllers including a Smith predictor (SP) can control time delayed plants. More specifically, it is shown to be more profitable to provide a PI controller with derivative action than with a SP for plants with long time delays.
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| 28. |
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| 29. |
- Martinsson, Bengt G., et al.
(författare)
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A high-sensitivity method for hydrogen analysis in thin targets
- 1993
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Ingår i: Nuclear Inst. and Methods in Physics Research, B. - 0168-583X. ; 82:4, s. 589-599
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Tidskriftsartikel (refereegranskat)abstract
- A sensitive and fast method for hydrogen analysis has been developed. The method is based on a technique where a proton beam of a few MeV impinges on the target and the elastically scattered proton and the recoiling target hydrogen nucleus are detected in coincidence. The method makes use of the difference in time of flight and requires no energy determination. The system consists of two thin, large-area plastic scintillation detectors placed at angles of 45° relative to the beam direction on either side of the beam. Evaluations of the system showed that a stable coincidence yield with respect to position in the target plane and target displacement can be obtained provided that the geometry of the setup is carefully designed. The yield as a function of target thickness was almost linear for target thicknesses up to 2000 μg/cm2. It was also found that count rates up to 500000 s-1 in each branch may be used. The minimum detection limit for the hydrogen detection system was found to be of the order of a few pg/cm2 for a proton beam energy of 3.6 MeV.
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| 30. |
- Olsen, Fredrik, 1973, et al.
(författare)
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Validation of the Nottingham Hip Fracture Score (NHFS) for the prediction of 30-day mortality in a Swedish cohort of hip fractures.
- 2021
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Ingår i: Acta anaesthesiologica Scandinavica. - : Wiley. - 1399-6576 .- 0001-5172. ; 65:10, s. 1413-1420
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Tidskriftsartikel (refereegranskat)abstract
- Hip fracture is a common osteoporotic fracture with great morbidity and mortality. The utility of ASA classification is limited, as most patients are ≥ASA 3. A reliable predictor of mortality risk could support decision-making. We aimed to evaluate Nottingham hip fracture score (NHFS) for the prediction of 30-day mortality and then to recalibrate the formula converting NHFS to risk of 30-day mortality.All patients >60years with surgically treated hip fracture surgery during 2015-16 were assessed. Data was extracted manually from routinely collected clinical data in registry and medical records. Discriminative performance of NHFS and ASA was assessed with C-statistics. The conversion formula from NHFS to risk of 30-day mortality was recalibrated using logistic binominal regression. Observed vs expected ratios of 30-day mortality were compared with the 2012NHFS-formula and recalibration was performed in a split dataset.1864 patients were included, with 213 deaths within 30days. C-statistic were 0.64 for NHFS and 0.62 for ASA. Comparing expected values from the 2012-revision with our observed deaths gave a ratio of 1.37. Relating predicted levels of 30-day mortality based on 70% of our cohort vs. 30% test portion of our Swedish dataset gave a ratio of 0.97.NHFS underestimated mortality in our cohort and showed poor discrimination. Revision of the formula based on a split dataset improved calibration. We suggest NHFS to be routinely implemented to support clinical judgements, expand preoperative assessment and escalate intraoperative monitoring.
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| 31. |
- Shariff, Asad, et al.
(författare)
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Evaluation of low-energy tailing parameters of a HPGe X-ray detector to be used in GUPIX software library for PIXE analysis
- 2004
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Ingår i: Nuclear Instruments & Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms. - : Elsevier BV. - 0168-583X. ; 219-20, s. 110-114
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Tidskriftsartikel (refereegranskat)abstract
- Accurate description of the response function of X-ray detectors is important for quantitative PIXE analysis. For analytical description of low-energy tailing in PIXE spectra, the GUPIX approach was used, i.e. a combination of Hypermate type functions. The low-energy tailing parameters of a low-energy high purity germanium X-ray detector in the region 1.3-9.2 keV was determined by systematic fitting of X-ray spectra from thin MicroMatter standards. Except for the main Gaussian peak and germanium escape peaks, one shelf, one truncated shelf, one exponential function and KMM radiative Auger feature was applied to fit the spectral data collected with this low-energy Ge X-ray detector. The overall trend of different tail parameters shows similar characteristic as those for Si(Li) X-ray detectors used in this energy range, i.e. very strong tailing at low X-ray energies and a rapid fall off with increasing X-ray energy. The fitted parameters, as a function of X-ray energy, were then incorporated into the GUPIX library for PIXE analysis. (C) 2004 Elsevier B.V. All rights reserved.
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| 32. |
- Stridsberg, Mats, et al.
(författare)
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Measurements of chromogranin B can serve as a complement to chromogranin A
- 2007
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Ingår i: Regulatory Peptides. - : Elsevier BV. - 0167-0115 .- 1873-1686. ; 139:1-3, s. 80-83
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Tidskriftsartikel (refereegranskat)abstract
- Objective CgA has been shown to be an excellent marker for neuroendocrine tumours. However, there are two major drawbacks with CgA measurements; elevated levels are common in patients with decreased renal function and in patients on treatment with proton pump inhibitors. These problems are not seen with CgB measurements. We have recently presented the development of 13 region-specific radioimmunoassays for measurements of CgB. A region-specific assay was identified, which measured higher concentrations of CgB than the other assays and seemed to be very useful as a marker for neuroendocrine tumours. The aim of the present study was therefore to further explore the diagnostic potential of this assay in the clinical management of patients with neuroendocrine tumours. Methods Measurements of CgB with two methods were compared with CgA in plasma samples from patients investigated for neuroendocrine tumours (N = 86), patients with decreased renal function (N = 35) and patients on treatment with proton pump inhibitors (N = 29). Results The diagnostic sensitivity for the new CgB assay was almost as good as that for CgA. Furthermore, with CgB measurements we could avoid the falsely elevated levels of CgA found in patients with decreased renal function and treatment with proton pump inhibitors. Conclusions We conclude that the new CgB assay can serve as a complement to CgA measurements as an important tumour marker for neuroendocrine tumours.
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| 35. |
- Öhman, David, et al.
(författare)
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Partially erupted third molars as a potential source of infection in patients receiving peripheral stem cell transplantation for malignant diseases: a retrospective study
- 2010
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Ingår i: European Journal of Oral Sciences. - : Wiley. - 0909-8836 .- 1600-0722. ; 118:1, s. 53-58
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Tidskriftsartikel (refereegranskat)abstract
- Forty-four patients with malignant diseases for which they received peripheral stem cell transplant therapy (PSCT) were retrospectively studied regarding local and systemic infection originating from around partially erupted third molars (PEMs). Twenty-two patients had one or more PEMs, while 22 patients had none. Data were retrieved from medical and dental records. Systemic and local signs of infection and treatment were assessed. We recorded the number of transplanted CD34(+) blood stem cells, days with white blood cell counts < 0.5 x 10(9) l(-1), days until engraftment, maximum level of C-reactive protein (CRP), days with fever, positive blood cultures, days taking antibiotics, days drinking < 0.5 l, days of total parenteral nutrition, days receiving intravenously administered analgesics, and number of admission days. No statistically significant difference was detected between patients with PEMs and those without PEMs regarding any of the studied parameters. Of patients with PEMs, 36% (8 of 22) developed local infections around PEMs during the PSCT period. The study indicates that PEMs pose no significant risk of causing systemic infection in patients receiving PSCT for malignant diseases but increase the risk of developing a local infection, justifying close supervision and early treatment in cases of local infection during PSCT treatment.
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