| 1. |
- Zamora, Juan Carlos, et al.
(författare)
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Considerations and consequences of allowing DNA sequence data as types of fungal taxa
- 2018
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Ingår i: IMA Fungus. - : INT MYCOLOGICAL ASSOC. - 2210-6340 .- 2210-6359. ; 9:1, s. 167-185
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Tidskriftsartikel (refereegranskat)abstract
- Nomenclatural type definitions are one of the most important concepts in biological nomenclature. Being physical objects that can be re-studied by other researchers, types permanently link taxonomy (an artificial agreement to classify biological diversity) with nomenclature (an artificial agreement to name biological diversity). Two proposals to amend the International Code of Nomenclature for algae, fungi, and plants (ICN), allowing DNA sequences alone (of any region and extent) to serve as types of taxon names for voucherless fungi (mainly putative taxa from environmental DNA sequences), have been submitted to be voted on at the 11th International Mycological Congress (Puerto Rico, July 2018). We consider various genetic processes affecting the distribution of alleles among taxa and find that alleles may not consistently and uniquely represent the species within which they are contained. Should the proposals be accepted, the meaning of nomenclatural types would change in a fundamental way from physical objects as sources of data to the data themselves. Such changes are conducive to irreproducible science, the potential typification on artefactual data, and massive creation of names with low information content, ultimately causing nomenclatural instability and unnecessary work for future researchers that would stall future explorations of fungal diversity. We conclude that the acceptance of DNA sequences alone as types of names of taxa, under the terms used in the current proposals, is unnecessary and would not solve the problem of naming putative taxa known only from DNA sequences in a scientifically defensible way. As an alternative, we highlight the use of formulas for naming putative taxa (candidate taxa) that do not require any modification of the ICN.
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| 2. |
- Alseekh, Saleh, et al.
(författare)
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Mass spectrometry-based metabolomics: a guide for annotation, quantification and best reporting practices
- 2021
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Ingår i: Nature Methods. - : Springer Science and Business Media LLC. - 1548-7091 .- 1548-7105. ; 18:7, s. 747-756
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Forskningsöversikt (refereegranskat)abstract
- This Perspective, from a large group of metabolomics experts, provides best practices and simplified reporting guidelines for practitioners of liquid chromatography- and gas chromatography-mass spectrometry-based metabolomics. Mass spectrometry-based metabolomics approaches can enable detection and quantification of many thousands of metabolite features simultaneously. However, compound identification and reliable quantification are greatly complicated owing to the chemical complexity and dynamic range of the metabolome. Simultaneous quantification of many metabolites within complex mixtures can additionally be complicated by ion suppression, fragmentation and the presence of isomers. Here we present guidelines covering sample preparation, replication and randomization, quantification, recovery and recombination, ion suppression and peak misidentification, as a means to enable high-quality reporting of liquid chromatography- and gas chromatography-mass spectrometry-based metabolomics-derived data.
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| 3. |
- Agrasada, Grace V., et al.
(författare)
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Exclusive breastfeeding of low birth weight infants for the first six months : infant morbidity and maternal and infant anthropometry
- 2011
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Ingår i: Asia Pacific Journal of Clinical Nutrition. - : H E C Press. - 0964-7058 .- 1440-6047. ; 20:1, s. 62-68
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Tidskriftsartikel (refereegranskat)abstract
- Background: to report anthropometry and morbidity among term low birth weight infants and anthropometry of their first time mothers during the first six months in relation to breastfeeding practice. Methods: we examined data from a randomized controlled trial in Manila, the Philippines. Of the 204 mothers randomized, 68 mothers received eight postpartum breastfeeding counseling sessions, the rest did not. Maternal and infant anthropometric data at birth, 2, 4 and 6 months were taken. During seven follow-up hospital visits, an independent interviewer recorded feeding data. Results: the 24 infants exclusively breastfed from birth to six months did not have diarrhea compared to 134 partially breastfed (mean 2.3 days) and 21 non-breastfed infants (mean 2.5 days). Partially breastfed and non-breastfed infants compared to exclusively breastfed infants had more frequent, as well as more severe episodes of respiratory infections. At six months, neither overall gain in infant weight, length and head circumferences nor mean maternal weight and body mass index differed significantly between the feeding groups. Conclusions: exclusive breastfeeding for 6 months can be recommended in term low birth weight infants, who were protected from diarrhea, had fewer respiratory infections, required no hospitalization and had catch up growth. Exclusively breastfeeding mothers did not differ from mothers who breastfed partially or those who did not breastfeed with regard to weight changes at six months.
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| 4. |
- Agrasada, Grace V., 1956-
(författare)
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Postnatal Peer Counseling on Exclusive Breastfeeding of Low-birthweight Filipino Infants : Results of a Randomized Controlled Trial
- 2005
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In a Manila hospital, 204 mothers were randomized into three groups: two intervention groups receiving home-based counseling visits, one of them (n=68) by counselors trained to use a locally developed, two-tiered program of breastfeeding counseling, and the other by counselors trained in general childcare (n=67), were compared with a control group of mothers (n=69) who did not receive any counseling. All infants were scheduled for seven visits to the hospital for follow-up. During hospital visits, maternal and infant body measurements were made and an independent interviewer asked the mothers individually to recall how the infant had been fed. One study physician, blind to participant groups, was consulted at all scheduled and unscheduled infant visits.At six months, 44% of the breastfeeding-counseled mothers, 7% of the childcare-counseled mothers and none of the mothers in the control group were exclusively breastfeeding. Twenty- four mothers breastfed exclusively during the first six months, of whom 22 received breastfeeding counseling and 2 had no breastfeeding counseling. Among 24 infants who were exclusively breastfed from birth to six months there were no episodes of diarrhea. All infants had gained in weight, length and head circumference. Mean maternal weight loss at six months was similar whether her breastfeeding was exclusive or partial.The reasons why mothers without breastfeeding counseling introduced non-breast milk feeding before six months reflected lack of knowledge and support. Breastfeeding support during the first six months focusing on how to prevent and solve breastfeeding problems, particularly during the first two weeks, will enable mothers to choose to breastfeed exclusively up to six months. This study has provided fundamental evidence of successful intervention by breastfeeding counseling to achieve six months of exclusive breastfeeding among term, low-birthweight infants. The locally developed training program in breastfeeding counseling, which successfully prepared volunteers to counsel mothers at home, could be incorporated into primary health care in the Philippines. Mothers who received breastfeeding counseling appreciated how this helped them to achieve their breastfeeding goals for the first six months. Improved breastfeeding practices as a result of breastfeeding counseling provided infants with protection from diarrhea and respiratory infections, contributing to their health and development.
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| 5. |
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| 6. |
- Ahlsson, Fredrik, 1967-, et al.
(författare)
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Adipokines and their relation to maternal energy substrate production, insulin resistance and fetal size
- 2013
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Ingår i: European Journal of Obstetrics, Gynecology, and Reproductive Biology. - : Elsevier BV. - 0301-2115 .- 1872-7654. ; 168:1, s. 26-29
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE:The role of adipokines in the regulation of energy substrate production in non-diabetic pregnant women has not been elucidated. We hypothesize that serum concentrations of adiponectin are related to fetal growth via maternal fat mass, insulin resistance and glucose production, and further, that serum levels of leptin are associated with lipolysis and that this also influences fetal growth. Hence, we investigated the relationship between adipokines, energy substrate production, insulin resistance, body composition and fetal weight in non-diabetic pregnant women in late gestation.STUDY DESIGN:Twenty pregnant women with normal glucose tolerance were investigated at 36 weeks of gestation at Uppsala University Hospital. Levels of adipokines were related to rates of glucose production and lipolysis, maternal body composition, insulin resistance, resting energy expenditure and estimated fetal weights. Rates of glucose production and lipolysis were estimated by stable isotope dilution technique.RESULTS:Median (range) rate of glucose production was 805 (653-1337)μmol/min and that of glycerol production, reflecting lipolysis, was 214 (110-576)μmol/min. HOMA insulin resistance averaged 1.5±0.75 and estimated fetal weights ranged between 2670 and 4175g (-0.2 to 2.7 SDS). Mean concentration of adiponectin was 7.2±2.5mg/L and median level of leptin was 47.1 (9.9-58.0)μg/L. Adiponectin concentrations (7.2±2.5mg/L) correlated inversely with maternal fat mass, insulin resistance, glucose production and fetal weight, r=-0.50, p<0.035, r=-0.77, p<0.001, r=-0.67, p<0.002, and r=-0.51, p<0.032, respectively. Leptin concentrations correlated with maternal fat mass and insulin resistance, r=0.76, p<0.001 and r=0.73, p<0.001, respectively. There was no correlation between maternal levels of leptin and rate of glucose production or fetal weight. Neither were any correlations found between levels of leptin or adiponectin and maternal lipolysis or resting energy expenditure.CONCLUSION:The inverse correlations between levels of maternal adiponectin and insulin resistance as well as endogenous glucose production rates indicate that low levels of adiponectin in obese pregnant women may represent one mechanism behind increased fetal size. Maternal levels of leptin are linked to maternal fat mass and its metabolic consequences, but the data indicate that leptin lacks a regulatory role with regard to maternal lipolysis in late pregnancy.
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| 7. |
- Ahlsson, Fredrik, 1967-
(författare)
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Being Born Large for Gestational Age : Metabolic and Epidemiological Studies
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Obesity is a major health problem in the Western world. Mean birth weight has increased during the last 25 years. One explanation is that the proportion of large for gestational age (LGA) infants has increased. Such infants risk developing obesity, cardiovascular disease and diabetes later in life. Despite the risk of neonatal hypoglycemia, their postnatal metabolic adaptation has not been investigated. Our data, obtained with stable isotope labeled compounds, demonstrate that newborn LGA infants have increased lipolysis and decreased insulin sensitivity. After administration of glucagon, the plasma levels of glucose and the rate of glucose production increased. The simultaneous increase in insulin correlated with the decrease in lipolysis, indicating an antilipolytic effect of insulin in these infants.We also demonstrated an intergenerational effect of being born LGA, since women born LGA, were at higher risk of giving birth to LGA infants than women not born LGA. Further, the LGA infants formed three subgroups: born long only, born heavy only, and born both long and heavy. Infants born LGA of women with high birth weight or adult obesity were at higher risk of being LGA concerning weight alone, predisposing to overweight and obesity at childbearing age. In addition we found that pregnant women with gestational diabetes were at increased risk of giving birth to infants that were heavy alone. This could explain the risk of both perinatal complications and later metabolic disease in infants of this group of women.To identify determinants of fetal growth, 20 pregnant women with a wide range of fetal weights were investigated at 36 weeks of gestation. Maternal fat mass was strongly associated with insulin resistance. Insulin resistance was related to glucose production, which correlated positively with fetal size. The variation in resting energy expenditure, which was closely related to fetal weight, was largely explained by BMI, insulin resistance, and glucose production. Lipolysis was not rate limiting for fetal growth in this group of women. Consequently, high maternal glucose production due to a high fat mass may result in excessive fetal growth.
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| 8. |
- Ahlsson, Fredrik, et al.
(författare)
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Insulin Resistance, a Link between Maternal Overweight and Fetal Macrosomia in Nondiabetic Pregnancies
- 2010
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Ingår i: Hormone research in paediatrics. - : S. Karger AG. - 1663-2818 .- 1663-2826. ; 74:4, s. 267-274
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Tidskriftsartikel (refereegranskat)abstract
- Background/Aims: During the last decades the number of large for gestational age infants delivered by nondiabetic mothers has increased. Our aim was to investigate to what extent fetal growth in nondiabetic pregnant women can be explained by rates of maternal energy substrate production and resting energy expenditure. Methods: Twenty nonsmoking pregnant women without impaired glucose tolerance and with a wide range of fetal weights (0.2-2.7 SDS) were investigated at 36 weeks of gestation. Maternal lipolysis, glucose production, resting energy expenditure, body composition and insulin resistance were assessed.Results: Median (range) glucose production rate was 805 (653-1,337) mumol/min and that of glycerol, reflecting lipolysis, was 214 (110-576) mumol/min. Multiple linear regression analysis showed that maternal fat mass explained 36% of the variation in insulin resistance, accounting for 62% of the variation in glucose production. Further, glucose production explained 31% of the variation in fetal weight. Resting energy expenditure explained 51% of the variation in estimated fetal weight. Conclusion: Fetal weight is dependent on maternal glucose production, which is in turn determined by the degree of insulin resistance, induced in part by the maternal fat mass. The variation in maternal resting energy expenditure is closely related to fetal weight.
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| 9. |
- Ahlsson, Fredrik, et al.
(författare)
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Lipolysis and Insulin Sensitivity at Birth in Infants Who Are Large for Gestational Age
- 2007
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Ingår i: Pediatrics. - : American Academy of Pediatrics (AAP). - 0031-4005 .- 1098-4275. ; 120:5, s. 958-965
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE. In addition to neonatal hypoglycemia, infants who are born large for gestational age are at risk for developing obesity, cardiovascular disease, and diabetes later in life. The aim of this study was to investigate glucose production, lipolysis, and insulin sensitivity in infants who were born large for gestational age to mothers without diabetes. The effect of glucagon administration on production of energy substrates was also investigated. METHODS. Ten healthy term infants who were born large for gestational age to mothers without diabetes were studied 16 ± 8 hours postnatally after a 3-hour fast. Rates of glucose production and lipolysis were analyzed by gas chromatography–mass spectrometry following constant rate infusion of [6,6-2H2]glucose and [2-13C]glycerol. Insulin sensitivity was assessed by the Homeostasis Assessment Model. In 8 of the infants, the effect of an intravenous injection of 0.2 mg/kg glucagon was also analyzed. RESULTS. Plasma glucose and glycerol averaged 3.8 ± 0.5 mmol/L and 384 ± 183 µmol/L, respectively. The glycerol production rate, reflecting lipolysis, was 12.7 ± 2.9 µmol/kg per min. Mean rate of glucose production was 30.2 ± 4.6 µmol/kg per min. Homeostasis Assessment Model insulin sensitivity corresponded to 82% ± 19%, β-cell function to 221% ± 73%, and insulin resistance to 1.3 ± 0.3. After glucagon administration, rate of glucose production increased by 13.3 ± 8.3 µmol/kg per min and blood glucose by 1.4 ± 0.5 mmol/L. Glycerol production decreased from 12.8 ± 3.0 to 10.7 ± 2.9 µmol/kg per min. Mean insulin concentration increased from 10.9 ± 3.0 to 30.9 ± 10.3 mU/L. There was a strong inverse correlation between the decrease in lipolysis and increase in insulin after glucagon administration. CONCLUSIONS. Infants who are born large for gestational age show increased lipolysis and a propensity for decreased insulin sensitivity already at birth. The simultaneous increase in plasma insulin correlated strongly with the noted decrease in lipolysis, indicating an antilipolytic effect of insulin in these infants.
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| 10. |
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| 11. |
- Andersson, Magnus, et al.
(författare)
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Structural Dynamics of Light-Driven Proton Pumps
- 2009
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Ingår i: Structure. - : Elsevier BV. - 0969-2126 .- 1878-4186. ; 17:9, s. 1265-1275
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Tidskriftsartikel (refereegranskat)abstract
- Bacteriorhodopsin and proteorhodopsin are simple heptahelical proton pumps containing a retinal chromophore covalently bound to helix G via a protonated Schiff base. Following the absorption of a photon, all-trans retinal is isomerized to a 13-cis conformation, initiating a sequence of conformational changes driving vectorial proton transport. In this study we apply time-resolved wide-angle X-ray scattering to visualize in real time the helical motions associated with proton pumping by bacteriorhodopsin and proteorhodopsin. Our results establish that three conformational states are required to describe their photocycles. Significant motions of the cytoplasmic half of helix F and the extracellular half of helix C are observed prior to the primary proton transfer event, which increase in amplitude following proton transfer. These results both simplify the structural description to emerge from intermediate trapping studies of bacteriorhodopsin and reveal shared dynamical principles for proton pumping.
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| 12. |
- Bernson, Elin, 1987, et al.
(författare)
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Cytomegalovirus Serostatus Affects Autoreactive NK Cells and Outcomes of IL2-Based Immunotherapy in Acute Myeloid Leukemia
- 2018
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Ingår i: Cancer Immunology Research. - : American Association for Cancer Research (AACR). - 2326-6066 .- 2326-6074. ; 6:9, s. 1110-1119
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Tidskriftsartikel (refereegranskat)abstract
- Human cytomegalovirus (CMV) infection is reported to promote NK cell differentiation and education. The CMV-induced generation of highly differentiated adaptive-like NK cells has been proposed to affect favorably on the maintenance of remission in patients with acute myeloid leukemia (AML) after allogeneic stem cell transplantation (allo-SCT). The impact of CMV infection and adaptive-like NK cells on relapse and survival of patients with AML not receiving allo-SCT remains unknown. We assayed CMV IgG serostatus to determine past CMV infection in 81 nontransplanted AML patients who were receiving relapse-prevention immunotherapy comprising histamine dihydrochloride and low-dose interleukin-2 (HDC/IL2; NCT01347996). CMV seropositivity correlated negatively with leukemia-free and overall survival of patients receiving HDC/IL2, but did not correlate with outcomes in a contemporary control cohort. Analysis of outcome after stratification of patients based on concordant or discordant killer immunoglobulin-like receptor (KIR) and HLA genotypes implied that the negative impact of CMV seropositivity was restricted to patients lacking a ligand to inhibitory KIRs (iKIR). Previous CMV infection was also associated with fewer NK cells expressing only nonself iKIRs (NS-iKIR). We propose that CMV-driven NK cell education depletes the population of NS-iKIR NK cells, which in turn reduces the clinical benefit of relapse-preventive immunotherapy in AML.
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| 13. |
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| 14. |
- Diderholm, Barbro, et al.
(författare)
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Energy substrate production in infants born small for gestational age
- 2007
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Ingår i: Acta Paediatrica. - : Wiley. - 0803-5253 .- 1651-2227. ; 96:1, s. 29-34
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Tidskriftsartikel (refereegranskat)abstract
- Aim: To investigate energy substrate production and its hormonal regulation in infants born small for gestational age. Methods: Eleven infants, aged 24.4 ± 5.3 hour, were studied following a fast of 4.0 ± 0.6 hour. Gestational age was 35.4 ± 2.8 weeks and birth weight 1804 ± 472 g (<−2 SD). Rates of glucose production and lipolysis were analyzed using [6,6-2H2]-glucose and [2-13C]-glycerol. Results: Plasma levels of glucose and glycerol were 4.1 ± 1.1 mmol . L−1 and 224 ± 79 μmol . L−1, respectively. Glucose appearance averaged 30.3 ± 8.2 and glucose production rate 21.1 ± 6.1 μmol . kg−1 . minutes−1. Glycerol production rate was 5.6 ± 1.6 μmol . kg−1 . minutes−1, correlating strongly to birth weight (r = 0.904, p < 0.001). Of the glycerol produced, 55 ± 22% was converted to glucose, corresponding to 8 ± 3% of the glucose production. Conclusions: Even though the infants could produce energy substrates, lipolysis was reduced and the glucose production was in the low end of the normal range compared with infants born appropriate for gestational age. The correlation between glycerol production and birth weight indicates that lipolysis depends on the amount of stored fat. Data on insulin and insulin-like growth factor binding protein 1 support the view that insulin sensitivity in these infants is reduced in the liver but increased peripherally.
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| 15. |
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| 16. |
- Diderholm, Barbro, 1965-
(författare)
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Perinatal Energy Substrate Metabolism : Glucose Production and Lipolysis in Pregnant Women and Newborn Infants with Particular Reference to Intrauterine Growth Restriction (IUGR)
- 2005
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Glucose is the most important fetal nutrient and the production of this substrate increases in the pregnant woman. In the last trimester the increased insulin resistance directs energy substrates to the fetus. Fetal growth is sometimes disturbed, often without an obvious explanation.After birth the newborn infant must produce its own glucose, primarily for the brain. Fatty acids from lipolysis are also important energy substrates. Hypoglycaemia can be a problem, occurring frequently in preterm infants and infants born small for gestational age (SGA). In addition, SGA infants are at risk of developing the metabolic syndrome in adulthood. Neonatal medication can influence energy metabolism. One such medication is theophylline, administered in preterm infants to prevent apnoea. We investigated energy substrate production in women with normal and IUGR pregnancies, in preterm neonates, before and after theophylline treatment and in newborn SGA infants, using stable isotope-labelled compounds and gas chromatography-mass spectrometry. We found that late pregnancy was associated with an almost twofold increase in the rate of lipolysis. This provides substrates for maternal energy metabolism, which may spare glucose for the fetus. Even though glucose production was comparable in the two groups of pregnant women, those with IUGR had a lower rate of lipolysis. A reduced supply of energy substrates could be one factor underlying IUGR. In spite of the insulin resistance of late pregnancy, insulin still had a regulatory role in energy substrate production in the women with normal pregnancies, but not in those with IUGR. Although infants born preterm and/or SGA have limited energy stores, we demonstrated that they are capable of both lipolysis and glucose production. Theophylline had no adverse effects on energy substrate production. Data on insulin and IGFBP-1 in the SGA infants indicate that in such infants insulin sensitivity is increased peripherally but reduced in the liver.
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| 17. |
- Ewald, Johannes, et al.
(författare)
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Acid-Cleavable Poly(ethylene glycol) Hydrogels Displaying Protein Release at pH 5
- 2020
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Ingår i: Chemistry - A European Journal. - : Wiley. - 0947-6539 .- 1521-3765. ; 26:13, s. 2947-2953
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Tidskriftsartikel (refereegranskat)abstract
- PEG is the gold standard polymer for pharmaceutical applications, however it lacks degradability. Degradation under physiologically relevant pH as present in endolysosomes, cancerous and inflammatory tissues is crucial for many areas. The authors present anionic ring‐opening copolymerization of ethylene oxide with 3,4‐epoxy‐1‐butene (EPB) and subsequent modification to introduce acid‐degradable vinyl ether groups as well as methacrylate (MA) units, enabling radical cross‐linking. Copolymers with different molar ratios of EPB, molecular weights (Mn) up to 10 000 g mol−1 and narrow dispersities (Đ<1.05) were prepared. Both the P(EG‐co‐isoEPB)MA copolymer and the hydrogels showed pH‐dependent, rapid hydrolysis at pH 5–6 and long‐term storage stability at neutral pH (pH 7.4). By designing the degree of polymerization and content of degradable vinyl ether groups, the release time of an entrapped protein OVA‐Alexa488 can be tailored from a few hours to several days (hydrolysis half‐life time t1/2 at pH 5: 13 h to 51 h).
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| 18. |
- Ferrari, Piero, et al.
(författare)
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The effect of radiative cooling on the size-dependent stability of small boron clusters
- 2018
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Ingår i: Physical Review A. Atomic, Molecular, and Optical Physics. - 1050-2947. ; 98
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Tidskriftsartikel (refereegranskat)abstract
- The mass spectrum of cationic boron clusters, BN+ (N = 5 − 20), after photoexcitation demonstrates that radiative cooling is an important, though often neglected, process in determining the relative stability of small and isolated particles. The observed intensities inmass spectra suggest that B5+, B11+, B13+, and B15+ are particularly stable clusters, consistent with density-functional theory calculations. Quantitative agreement, however, is only obtained if radiative cooling is included in the analysis.All clusters are found to radiate onmicrosecond timescales, suggesting recurrent fluorescence as the dominant photon emission process.
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| 19. |
- Grosselindemann, C., et al.
(författare)
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Impact of CeCo-Coated Metallic Interconnectors on SOCs Towards Performance, Cr-Oxide-Scale, and Cr-Evaporation
- 2024
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Ingår i: Journal of the Electrochemical Society. - 1945-7111 .- 0013-4651. ; 171:5
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Tidskriftsartikel (refereegranskat)abstract
- The performance of a solid oxide cell (SOC) depends on the operating environment. Regarding single cell tests with ideal contacting (gold, platinum, nickel meshes) and inert flow fields (Al2O3), performance is limited by intrinsic losses in the cell. Contact losses and poisoning effects are minimized. In a SOC-stack with metallic interconnectors, performance is affected by contact resistances, chromium (Cr) evaporation, and limitations in gas supply. Here, 1 cm2 single cells were tested with a stack-like contact applying metallic flow fields made from three different steel grades (Crofer 22 APU, AISI 441, UNS S44330) with and without a cerium-cobalt PVD-coating. Cell performance and losses were analyzed by IV-characteristics, impedance spectroscopy, and DRT analysis. For all uncoated interconnectors, significant performance losses due to increased contact losses and air electrode polarization were observed, which is attributed to Cr-oxide scale formation on the metallic interconnectors and Cr-poisoning of the air electrode as revealed by scanning electron microscopy-energy-dispersive X-ray spectroscopy. A CeCo-coating leads to similar oxide scales irrespective of the substrate material. Moreover, with the coating the electrochemical performance drastically improved due to decreased contact losses and an effective blocking of Cr-evaporation leading to a cell performance close to the ideal case for all three steel grades.
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| 20. |
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| 21. |
- Pandita, Ankur, et al.
(författare)
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Intussusceptive angiogenesis in human metastatic malignant melanoma. : Intussusception in human melanoma
- 2021
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Ingår i: The American Journal of Pathology. - : Elsevier BV. - 1525-2191 .- 0002-9440. ; 191:11, s. 2023-2038
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Tidskriftsartikel (refereegranskat)abstract
- Angiogenesis supplies oxygen and nutrients to growing tumors. Inhibiting angiogenesis may stop tumor growth, but vascular endothelial growth factor inhibitors have limited effect in most tumors. The limited effect may be explained by an additional, less vascular endothelial growth factor-driven, form of angiogenesis known as intussusceptive angiogenesis. The importance of intussusceptive angiogenesis in human tumors is not known. Epifluorescence and confocal microscopy was used to visualize intravascular pillars, the hallmark structure of intussusceptive angiogenesis, in tumors. Human malignant melanoma metastases, patient-derived melanoma xenografts in mice (PDX), and genetically engineered BRAF-induced, PTEN-deficient (BPT) mice (BrafCA/+Ptenf/fTyr-Cre+/0-mice) were analyzed for pillars. Gene expression in human melanoma metastases and PDXs was analyzed by RNA sequencing. Matrix metalloproteinase 9 (MMP9) protein expression and T-cell and macrophage infiltration in tumor sections were determined with multiplex immunostaining. Intravascular pillars were detected in human metastases but rarely in PDXs and not in BPT mice. The expression of MMP9 mRNA was higher in human metastases compared with PDXs. High expression of MMP9 protein as well as infiltration of macrophages and T-cell infiltration were detected in proximity to intravascular pillars. MMP inhibition blocked formation of pillars, but not tubes or tip cells, invitro. In conclusion, intussusceptive angiogenesis may contribute to the growth of human melanoma metastases. MMP inhibition blocked pillar formation invitro and should be further investigated as a potential anti-angiogenic drug target in metastatic melanoma.
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| 22. |
- Schmidt, Mischa, et al.
(författare)
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Experiences with large-scale operational trials of ALTO-enhanced P2P filesharing in an intra-ISP scenario
- 2013
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Ingår i: Peer-to-Peer Networking and Applications. - : Springer Science and Business Media LLC. - 1936-6442 .- 1936-6450. ; 6:2, s. 134-154
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Tidskriftsartikel (refereegranskat)abstract
- Application Layer Traffic Optimization (ALTO) has recently gained attention in the research and standardisation community as a way for a network operator to guide the peer selection process of distributed applications by providing network layer topology information. In particular P2P applications are expected to gain from ALTO, due to the many connections peers form among each other, often without taking network layer topology information into account. In this paper, we present results of an extensive intra-ISP trial with an ALTO-enhanced P2P filesharing software. In summary, our results show that—depending on the concrete setting and on the distribution of upload capacity in the network—ALTO enables an ISP to save operational costs significantly while not degrading application layer performance noticeably. In addition, based on our experience we are able to give advice to operators on how to save costs with ALTO while not sacrificing application layer performance at all.
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| 23. |
- Seedorf, Jan, et al.
(författare)
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Towards Operator-managed P2P Content Delivery with Application Layer Traffic Optimization
- 2010
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Konferensbidrag (refereegranskat)abstract
- P2P technology provides a flexible and very popular way of content delivery for various services, including networked media applications. However, P2P-based content delivery generates large amount of backbone traffic. Recently, several approaches have been proposed for guiding P2P services based on operator preferences, in order to reduce the amount of costly backbone traffic generated by P2P applications. Application Layer Traffic Optimization (ALTO) is a one key approach for such managed P2P applications. In short, ALTO is a dedicated service, operated by a network operator or ISP, which can provide useful network layer information to application layer clients for improved peer selection and corresponding content delivery. This paper provides an overview of standardisation and research activities for improving P2P content delivery with ALTO which are carried out within the EU FP7 project NAPA-WINE. In particular, we give an overview on standardisation efforts, present simulation results, explain our prototypical implementation of the ALTO concept, and highlight ongoing large-scale operational trials we are currently conducting within the network of Polish Telecom and among NAPA-WINE partners
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