| 41. |
- Hallberg, R. T., et al.
(author)
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Hydrogen-assisted spark discharge generated metal nanoparticles to prevent oxide formation
- 2018
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In: Aerosol Science and Technology. - : Informa UK Limited. - 0278-6826 .- 1521-7388. ; 52:3, s. 347-358
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Journal article (peer-reviewed)abstract
- There exists a demand for production of metal nanoparticles for today's emerging nanotechnology. Aerosol-generated metal nanoparticles can oxidize during particle formation due to impurities in the carrier gas. One method to produce unoxidized metal nanoparticles is to first generate metal oxides and then reduce them during sintering. Here, we propose to instead prevent oxidation by introducing the reducing agent already at particle formation. We show that by mixing 5% hydrogen into the nitrogen carrier gas, we can generate single crystalline metal nanoparticles by spark discharge from gold, cobalt, bismuth, and tin electrodes. The non-noble nanoparticles exhibit signs of surface oxidation likely formed post-deposition when exposed to air. Nanoparticles generated without hydrogen are found to be primarily polycrystalline and oxidized. To demonstrate the advantages of supplying the reducing agent at generation, we compare to nanoparticles that are generated in nitrogen and sintered in a hydrogen mixture. For bismuth and tin, the crystal quality of the particles after sintering is considerably higher when hydrogen is introduced at particle generation compared to at sintering, whereas for cobalt it is equally effective to only add hydrogen at sintering. We propose that hydrogen present at particle generation prevents the formation of oxide primary particles, thus improving the ability to sinter the nanoparticles to compact and single crystals of metal. This method is general and can be applied to other aerosol generation systems, to improve the generation of size-controlled nanoparticles of non-noble metals with a suitable reducing agent.
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| 42. |
- Kang, Xiaoying, et al.
(author)
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Association between Microscopic Colitis and Parkinson's Disease in a Swedish Population
- 2021
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In: Movement Disorders. - : Wiley. - 0885-3185 .- 1531-8257. ; 96:15
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Journal article (peer-reviewed)abstract
- Background: Gastrointestinal inflammation has been linked with Parkinson's disease (PD). Microscopic colitis (MC) is an intestinal inflammatory disease with unknown relationship with PD.Objective: This study aimed to examine the association of MC with PD risk.Methods: In this nationwide matched cohort study in Sweden, PD incidence was compared between 12,609 patients with histologically confirmed MC and a matched population cohort of 58,879 MC-free individuals and a sibling cohort comprising all unaffected siblings of the MC patients (N-MC/N-Sibling = 6281/12,351). Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox regression models.Results: During a mean follow-up of similar to 7 years, we identified 449 incident PD diagnoses among the MC patients and the population cohort. Overall, MC was associated with an adjusted HR of 1.76 for PD, but the association attenuated substantially during follow-up. In the time-varying effects model, PD hazard was 3.45-fold (95% CI: 2.42, 4.93) higher during the first 2 years after biopsy and 1.80-fold (95% CI: 1.23, 2.64) higher during the following 3 years among MC versus MC-free individuals but was not different beyond 5 years after biopsy (HR: 1.03; 95% CI: 0.68, 1.54). This temporal pattern of MC-PD associations persisted when comparing MC patients to their siblings. In a post hoc case-control analysis, we also detected a strong association between MC and preexisting PD (odds ratio: 3.46; 95% CI: 2.91, 4.12).Conclusions: Our findings suggest that MC may not be a risk factor for PD; instead, it may co-occur with PD as a comorbidity or develop after a diagnosis of PD.
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| 43. |
- Kang, Xiaoying, et al.
(author)
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Clostridium difficile infection and risk of Parkinson's disease : A Swedish population-based cohort study
- 2020
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In: European Journal of Neurology. - : Blackwell Publishing. - 1351-5101 .- 1468-1331. ; 27:11, s. 2134-2141
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Journal article (peer-reviewed)abstract
- BACKGROUND: Gastrointestinal inflammation has been implicated in Parkinson's disease (PD). This study examined whether individuals with a history of Clostridium difficile infection (CDI) are at elevated risk of PD.METHODS: We performed a population-based cohort study using Swedish national register data. Adults aged ≥ 35 years were identified from the Swedish Population and Housing Census 1990 and followed during 1997-2013. Diagnoses of CDI and PD were extracted from the National Patient Register. Associations of CDI history with PD risk were estimated using Cox proportional hazards regression. We also explored whether the association differed by the source of CDI diagnosis (inpatient vs outpatient), presence of recurrent infections, and pre-infection use of antibiotics.RESULTS: Amongst the study population (N = 4,670,423), 34,868 (0.75%) had a history of CDI. A total of 165 and 47,035 incident PD cases were identified from individuals with and without CDI history, respectively. Across the entire follow-up, a 16% elevation of PD risk was observed among CDI group (hazard ratio: 1.16, 95% confidence interval: 1.00-1.36), which was mainly driven by increased PD risk within the first 2 years since CDI diagnosis (hazard ratio: 1.38, 95% confidence interval: 1.12-1.69). In longer follow-up, CDI was not associated with subsequent PD occurrence. This temporal pattern of CDI-PD associations was generally observed across all CDI subgroups.CONCLUSIONS: CDI may be associated with an increased short-term PD risk, but this might be explained by reverse causation and/or surveillance bias. Our results do not imply that CDI history affects long-term PD risk.
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| 44. |
- Kohut, A., et al.
(author)
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From plasma to nanoparticles : Optical and particle emission of a spark discharge generator
- 2017
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In: Nanotechnology. - : IOP Publishing. - 0957-4484 .- 1361-6528. ; 28:47
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Journal article (peer-reviewed)abstract
- The increased demand for high purity nanoparticles (NPs) of defined geometry necessitates the continuous development of generation routes. One of the most promising physical techniques for producing metal, semiconductor or alloy NPs in the gas phase is spark discharge NP generation. The technique has a great potential for up-scaling without altering the particles. Despite the simplicity of the setup, the formation of NPs in a spark discharge takes place via complex multi-scale processes, which greatly hinders the investigation via conventional NP measurement techniques. In the present work, time-resolved optical emission spectroscopy (OES) was used to provide information on the species present in the spark from as early as approximately 100 ns after the initiation of the discharge. We demonstrate that operando emission spectroscopy can deliver valuable insights into NP formation. The emission spectra of the spark are used to identify, among others, the main stages of material erosion and to calculate the quenching rate of the generated metal vapour. We demonstrate that the alteration of key control parameters, that are typically used to optimize NP generation, clearly affect the emission spectra. We report for Cu and Au NPs that the intensity of spectral lines emitted by metal atoms levels off when spark energy is increased above an energy threshold, suggesting that the maximum concentration of metal vapour produced in the generator is limited. This explains the size variation of the generated NPs. We report a strong correlation between the optical and particle emission of the spark discharge generator, which demonstrate the suitability of OES as a valuable characterization tool that will allow for the more deliberate optimization of spark-based NP generation.
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| 45. |
- Liu, Bojing, et al.
(author)
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β2-adrenoreceptor agonists, montelukast, and Parkinson's disease risk
- 2023
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In: Annals of Neurology. - : John Wiley & Sons. - 0364-5134 .- 1531-8249. ; 93:5, s. 1023-1028
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Journal article (peer-reviewed)abstract
- Objective: This study was undertaken to examine the association between montelukast use, beta 2-adrenoreceptor (beta 2AR) agonist use, and later Parkinson disease (PD).Methods: We ascertained use of beta 2AR agonists (430,885 individuals) and montelukast (23,315 individuals) from July 1, 2005 to June 30, 2007, and followed 5,186,886 PD-free individuals from July 1, 2007 to December 31, 2013 for incident PD diagnosis. We estimated hazard ratios and 95% confidence intervals using Cox regressions.Results: We observed 16,383 PD cases during on average 6.1 years of follow-up. Overall, use of beta 2AR agonists and montelukast were not related to PD incidence. A 38% lower PD incidence was noted among high-dose montelukast users when restricted to PD registered as the primary diagnosis.Interpretation: Overall, our data do not support inverse associations between beta 2AR agonists, montelukast, and PD. The prospect of lower PD incidence with high-dose montelukast exposure warrants further investigation, especially with adjustment for high-quality data on smoking. ANN NEUROL 2023
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| 46. |
- Liu, Po-Hong, et al.
(author)
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Dietary Gluten Intake and Risk of Microscopic Colitis Among US Women without Celiac Disease : A Prospective Cohort Study
- 2019
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In: American Journal of Gastroenterology. - : Blackwell Publishing. - 0002-9270 .- 1572-0241. ; 114:1, s. 127-134
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Journal article (peer-reviewed)abstract
- OBJECTIVE: Microscopic colitis is a common cause of chronic watery diarrhea among the elderly. Although the prevalence of celiac disease appears to be higher in patients with microscopic colitis, the relationship between dietary gluten intake and risk of microscopic colitis among individuals without celiac disease has not been explored.METHODS: We conducted a prospective study of 160,744 US women without celiac disease enrolled in the Nurses' Health Study (NHS) and the NHSII. Dietary gluten intake was estimated using validated food frequency questionnaires every 4 years. Microscopic colitis was confirmed through medical records review. We used Cox proportional hazard modeling to estimate the multivariable-adjusted hazard ratio (HR) and 95% confidence interval (CI).RESULTS: We documented 219 incident cases of microscopic colitis over more than 20 years of follow-up encompassing 3,716,718 person-years (crude incidence rate: 5.9/100,000 person-years) in NHS and NHSII. Dietary gluten intake was not associated with risk of microscopic colitis (Ptrend = 0.88). Compared to individuals in the lowest quintile of energy-adjusted gluten intake, the adjusted HR of microscopic colitis was 1.18 (95% CI: 0.77-1.78) for the middle quintile and 1.03 (95% CI: 0.67-1.58) for the highest quintile. Additional adjustment for primary dietary sources of gluten including refined and whole grains did not materially alter the effect estimates (All Ptrend ≥ 0.69). The null association did not differ according to lymphocytic or collagenous subtypes (Pheterogeneity = 0.72) and was not modified by age, smoking status, or body mass index (All Pinteraction ≥ 0.17).CONCLUSION: Dietary gluten intake during adulthood was not associated with risk of microscopic colitis among women without celiac disease.
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| 47. |
- Lopes, Emily W., et al.
(author)
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Dietary Gluten Intake Is Not Associated With Risk of Inflammatory Bowel Disease in US Adults Without Celiac Disease
- 2022
-
In: Clinical Gastroenterology and Hepatology. - : Elsevier. - 1542-3565 .- 1542-7714. ; 20:2, s. 303-313.e6
-
Journal article (peer-reviewed)abstract
- BACKGROUND & AIMS: Diet is thought to play a role in the development of inflammatory bowel disease (IBD), though the relationship between gluten intake and risk of IBD has not been explored. The aim of this study was to determine the relationship between gluten intake and risk of incident Crohn's disease (CD) and ulcerative colitis (UC).METHODS: We performed a prospective cohort study of 208,280 US participants from the Nurses' Health Study (NHS; 1986-2016), NHSII (1991-2017), and Health Professionals Follow-up Study (1986-2016) who did not have IBD at baseline or celiac disease, and who completed semi-quantitative food frequency questionnaires. We used Cox proportional hazards modeling to estimate the risk of IBD according to quintiles of cumulative average energy-adjusted dietary gluten intake over follow-up period.RESULTS: We documented 337 CD cases and 447 UC cases over 5,115,265 person-years of follow-up evaluation. Dietary gluten intake was not associated with risk of IBD. Compared with participants in the lowest quintile of gluten intake, the adjusted hazard ratios and 95% CIs for participants in the highest quintile of gluten intake were 1.16 (95% CI, 0.82-1.64; P-trend = .41) for CD and 1.04 (95% CI, 0.75-1.44; P-trend = .64) for UC. Adjusting for primary sources of gluten intake did not materially change our estimates.CONCLUSIONS: In three large adult US prospective cohorts, gluten intake was not associated with risk of CD or UC. Our findings are reassuring at a time when consumption of gluten has been increasingly perceived as a trigger for chronic gastrointestinal diseases.
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| 48. |
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| 49. |
- Ludvigsson, Jonas, et al.
(author)
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Elemental versus polymeric enteral nutrtion in paediatric Crohn´s disease : a multicentre randomized controlled trial.
- 2004
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In: Acta Paediatrica. - 0803-5253 .- 1651-2227. ; 93, s. 327-335
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Journal article (peer-reviewed)abstract
- Aim: To compare the efficacy and safety of an elemental and a polymeric diet as the primary therapy for active Crohn's disease in children. Methods: In a randomized, non-blind, multicentre, controlled trial in Sweden, 16 children with Crohn's disease received Elemental 028 Extra (E028E) and 17 Nutrison Standard (NuS). Remission rates (Paediatric Crohn's Disease Activity Index (PCDAI) < 10 or a PCDAI decrease of 40% or 15 points of initial level) were compared at 6 wk. Results: There was no significant difference between the two groups in remission rate at 6 wk (intent-to-treat analysis): E028E 11/16 (69%) and NuS 14/17 (82%) (p = 0.438). There was no difference in the decrease in PCDAI and CDAI between patients treated with E028E and those treated with NuS from 0 to 6 wk. Patients treated with NuS gained significantly more weight than patients treated with E028E (+2.5 kg, 95% CI 0.9, 4.1, p = 0.004), this difference remained when adjusting for maximum caloric intake per kilogram bodyweight (+2.9 kg, 95% CI 1.4, 4.5, p = 0.001). Concomitant disease, complications and side effects were seen in 5/33 patients (pyelonephritis, pneumonia, intraabdominal abscess, perianal abscess and borborygmi). Conclusion: E028E and NuS did not differ in terms of remission rate. Patients treated with NuS gained more weight than patients with E028E. Polymeric diet may be superior to elemental diet in the treatment of paediatric Crohn's disease where the primary aim is to increase the patient's weight.
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| 50. |
- Ludvigsson, Jonas F., 1969-, et al.
(author)
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Diagnosis and management of adult coeliac disease : guidelines from the British Society of Gastroenterology
- 2014
-
In: Gut. - : BMJ Publishing Group Ltd. - 0017-5749 .- 1468-3288. ; 63:8, s. 1210-1228
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Journal article (peer-reviewed)abstract
- A multidisciplinary panel of 18 physicians and 3 non-physicians from eight countries (Sweden, UK, Argentina, Australia, Italy, Finland, Norway and the USA) reviewed the literature on diagnosis and management of adult coeliac disease (CD). This paper presents the recommendations of the British Society of Gastroenterology. Areas of controversies were explored through phone meetings and web surveys. Nine working groups examined the following areas of CD diagnosis and management: classification of CD; genetics and immunology; diagnostics; serology and endoscopy; follow-up; gluten-free diet; refractory CD and malignancies; quality of life; novel treatments; patient support; and screening for CD.
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