12 research outputs found
Synthesis of phosphonium ionic liquids and their usage in alcohol dehydration reactions
No full textFosfonija grupu saturošo jonu šķidrumu sintēze un to izmantošana spirtu dehidratācijas reakcijās. Balode A.M., zinātniskais vadītājs Dr. ķīm., asoc. prof. Prikšāne A. Bakalaura darbs, 57 lappuses, 19 attēli, 15 tabulas, 31 literatūras avots, 10 pielikumi. Latviešu valodā. Darbā tiek veikta cviterjona sāls sintēze no trifenilfosfonija ar 1,3-propānsultonu. Iegūtā cviterjona sāls tīrība pārbaudīta ar 1H KMR, tālāk to izmanto skābo jonu šķidrumu iegūšanai ar p-toluolsulfonskābes monohidrātu un sērskābi. Ar iegūtajiem jonu šķidrumiem tālāk tiek pētītas spirtu dehidratācijas reakcijas, attiecīgi mainot reakcijas laiku un katalizatora un izejvielas attiecības.Synthesis of phosphonium ionic liquids and their usage in alcohol dehydration reactions. Balode A.M., scientific supervisor Dr. chem., asoc. Prof. Prikšāne A., Bachelor’s thesis in organic chemistry, 57 pages, 19 figures, 15 tables, 31 literature references, 10 appendices. In Latvian. Synthesis of zwitterion salt using triphenylphosphine and 1,3-propane sultone are investigated. For the identification 1H NMR is used. The zwitterion salt is used for ionic liquid synthesis using p-toluenesulfonic acid (monohydrate) and sulfuric acid. After that prepared ionic liquids are used for dehydration reactions of alcohols, changing reaction time and catalyst and alcohol ratio
Possibility of extraction and characterization of essential oils from Glechoma hederacea plant grown in territory of Latvia
No full textĒterisko eļļu ieguves un raksturošanas iespējas no Latvijas teritorijā audzētā Glechoma hederacea auga. Balode A.M., zinātniskais vadītājs Dr.ķīm. Nakurte I. Maģistra darbs, 80 lappuses, 19 attēli, 18 tabulas, 67 literatūras avoti, 5 pielikumi. Latviešu valodā. Darbā veikta vispārīga literatūras izpēte par ārstniecības augos esošajām ēteriskajām eļļām un to raksturošanas metodēm. Apskatā apkopota informācija par Efeju sētložņas (Glechoma hederacea) ķīmisko sastāvu, tās fitoķīmiskajām īpašībām un pretvīrusu aktivitāti. Eksperimentālajā daļā veikta Latvijas teritorijā gan savvaļā augušas, gan kontrolētos apstākļos audzētas Efeju sētložņas ēterisko eļļu iegūšana, izmantojot hidrodestilācijas metodi. Kā arī veikta izpēte, kā mainās dažādu Efeju sētložņas genotipu paraugu ēteriskās eļļas daudzums un ķīmiskais sastāvs dažādos tās veģetācijas periodos. Ķīmiskā sastāva novērtēšanai izmantota gan gāzu hromatogrāfijas masspektrometrijas metode, gan tvaika fāzes gāzu hromatogrāfijas metode.Possibility of extraction and characterization of essential oils from Glechoma hederacea plant grown in territory of Latvia. Balode A.M., scientific supervisor Dr. chem. Nakurte I. Master’s thesis in physical chemistry, 80 pages, 19 figures, 18 tables, 67 literature references, 5 appendixes. In Latvian. The general research of the literature on essential oils in medicinal plants and their characterization methods is performed in the work. The review summarizes the information on the chemical composition, phytochemical properties and antiviral activity of Ground Ivy (Glechoma hederacea). In the experimental part extraction of essential oils from Ground Ivy harvested in the wild and under controlled conditions in territory of Latvia was performed using hydrodistillation method. As well as it was investigated how Ground Ivy genotypes and time of harvesting can affect the amount of essential oil and its chemical composition. Gas chromatography mass spectrometry method and Headspace gas chromatography method was used to evaluate the chemical composition
Synthesis of Symmetric Ethers Using Monocationic and Dicationic Acidic Ionic Liquids
No full textA series of monocationic and dicationic -SO3H functionalized Brønsted acidic ionic liquids (BAILs) are synthesized using different amines int.al., N,N,N′,N′-tetramethylethylenediamine, 1-methylimidazole, pyridine and alkylating agents 1,3-propane- and 1,4-butanesultones. The Hammett acidity (H0) and thermal properties by TG-DSC techniques are investigated. These ionic liquids have been applied to catalyze the dehydration reaction of aliphatic long chain alcohols (1-heptanol, 1-octanol, 1-decanol) at 195 °C. The optimization of reaction conditions and use of dicationic ionic liquids allow to reach rather high yields of symmetric diheptyl ether and dioctyl ether. The reusability of ionic liquids is evaluated using monocationic [PyPS][HSO4], dicationic [TMEDAPS][HSO4] ionic liquids and 1-heptanol.</jats:p
Are children with prolonged fever at a higher risk for serious illness? : A prospective observational study
Get PDFFunding Information: This project received funding from the European Union’s Horizon 2020 research and innovation programme (Grant Agreement No 668303). The research was supported by the National Institute for Health Research Biomedical Research Centres at Imperial College London, Newcastle Hospitals NHS Foundation Trust and Newcastle University. RGN was funded by NIHR ACL award (ACL-2018-021-007). Funding Information: This project received funding from the European Union's Horizon 2020 research and innovation programme (Grant Agreement No 668303). The research was supported by the National Institute for Health Research Biomedical Research Centres at Imperial College London, Newcastle Hospitals NHS Foundation Trust and Newcastle University. RGN was funded by NIHR ACL award (ACL-2018- 021-007). Publisher Copyright: © 2023 Author(s) (or their employer(s)).Objectives: To describe the characteristics and clinical outcomes of children with fever ≥5 days presenting to emergency departments (EDs). Design: Prospective observational study. Setting: 12 European EDs. Patients: Consecutive febrile children 0.90, but were observed infrequently (range: 0.4%-17%). Absence of warning signs was not sufficiently reliable to rule out SBI (sensitivity 0.92 (95% CI 0.87-0.95), negative likelihood ratio (LR) 0.34 (0.22-0.54)). CRP <20 mg/L was useful for ruling out SBI (negative LR 0.16 (0.11-0.24)). There were 66 cases (1.7%) of non-infectious serious illnesses, including 21 cases of Kawasaki disease (0.6%), 28 inflammatory conditions (0.7%) and 4 malignancies. Conclusion: Children with prolonged fever have a higher risk of SBI, warranting a careful clinical assessment and diagnostic workup. Warning signs of SBI occurred infrequently but, if present, increased the likelihood of SBI. Although rare, clinicians should consider important non-infectious causes of prolonged fever.Peer reviewe
Impact of infection on proteome-wide glycosylation revealed by distinct signatures for bacterial and viral pathogens
Get PDFFunding Information: This research, part of the PERFORM project, has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No. 668303 . The samples collected previously were funded by: the European Seventh Framework Programme for Research and Technological Development ( FP7 ) under EUCLIDS Grant Agreement No. 279185 . Funding Information: This research, part of the PERFORM project, has received funding from the European Union's Horizon 2020 research and innovation program under grant agreement No. 668303. The samples collected previously were funded by: the European Seventh Framework Programme for Research and Technological Development (FP7) under EUCLIDS Grant Agreement No. 279185. We would like to thank all the patients and the healthy controls for donating their blood for the EUCLIDS, IRIS, and Westra studies. We would like to thank the Radboud Consortium for Glycoscience for their advice for data interpretation. We also thank the PERFORM consortium (see supplemental material for all participants) for their collaboration and fruitful discussions. Conceptualization, E.W. H.W. and M.J.; Methodology, E.W. M.D. H.W. and M.J.; Investigation, E.W.; Software, A.S. and H.W.; Formal Analysis, E.W. and H.W.; Visualization, E.W. and H.W.; Resources, M.F. L.H. N.K. R.P. M.K. V.W. J.H. and F.M.; Writing – Original Draft, E.W. and M.J.; Writing – Review & Editing, E.W. J.G. A.S. M.F. L.H. N.K. R.P. M.D. M.K. V.W. J.H. F.M. M.L. R.G. A.G. D.L. H.W. and M.J.; Funding Acquisition, M.J. R.G. and M.L.; Supervision, H.W. D.L. and M.J. The authors declare no competing interests. We support inclusive, diverse, and equitable conduct of research. Publisher Copyright: © 2023 The Author(s)Mechanisms of infection and pathogenesis have predominantly been studied based on differential gene or protein expression. Less is known about posttranslational modifications, which are essential for protein functional diversity. We applied an innovative glycoproteomics method to study the systemic proteome-wide glycosylation in response to infection. The protein site-specific glycosylation was characterized in plasma derived from well-defined controls and patients. We found 3862 unique features, of which we identified 463 distinct intact glycopeptides, that could be mapped to more than 30 different proteins. Statistical analyses were used to derive a glycopeptide signature that enabled significant differentiation between patients with a bacterial or viral infection. Furthermore, supported by a machine learning algorithm, we demonstrated the ability to identify the causative pathogens based on the distinctive host blood plasma glycopeptide signatures. These results illustrate that glycoproteomics holds enormous potential as an innovative approach to improve the interpretation of relevant biological changes in response to infection.Peer reviewe
Raising AWaRe-ness of antimicrobial stewardship challenges in pediatric emergency care : results from the PERFORM study assessing consistency and appropriateness of antibiotic prescribing across Europe
Get PDFPublisher Copyright: © The Author(s) 2023. Published by Oxford University Press on behalf of Infectious Diseases Society of America.Background. Optimization of antimicrobial stewardship is key to tackling antimicrobial resistance, which is exacerbated by overprescription of antibiotics in pediatric emergency departments (EDs). We described patterns of empiric antibiotic use in European EDs and characterized appropriateness and consistency of prescribing. Methods. Between August 2016 and December 2019, febrile children attending EDs in 9 European countries with suspected infection were recruited into the PERFORM (Personalised Risk Assessment in Febrile Illness to Optimise Real-Life Management) study. Empiric systemic antibiotic use was determined in view of assigned final “bacterial” or “viral” phenotype. Antibiotics were classified according to the World Health Organization (WHO) AWaRe classification. Results. Of 2130 febrile episodes (excluding children with nonbacterial/nonviral phenotypes), 1549 (72.7%) were assigned a bacterial and 581 (27.3%) a viral phenotype. A total of 1318 of 1549 episodes (85.1%) with a bacterial and 269 of 581 (46.3%) with a viral phenotype received empiric systemic antibiotics (in the first 2 days of admission). Of those, the majority (87.8% in the bacterial and 87.0% in the viral group) received parenteral antibiotics. The top 3 antibiotics prescribed were third-generation cephalosporins, penicillins, and penicillin/β-lactamase inhibitor combinations. Of those treated with empiric systemic antibiotics in the viral group, 216 of 269 (80.3%) received ≥1 antibiotic in the “Watch” category. Conclusions. Differentiating bacterial from viral etiology in febrile illness on initial ED presentation remains challenging, resulting in a substantial overprescription of antibiotics.Peer reviewe
Guideline adherence in febrile children below 3 months visiting European Emergency Departments : an observational multicenter study
Get PDFFunding Information: This project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No. 848196. The Research was supported by the National Institute for Health Research Biomedical Research Centres at Imperial College London, Newcastle Hospitals NHS Foundation Trust and Newcastle University. The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR or the Department of Health. For the remaining authors, no sources of funding were declared. The funding sources had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication. Publisher Copyright: © 2022, The Author(s).Febrile children below 3 months have a higher risk of serious bacterial infections, which often leads to extensive diagnostics and treatment. There is practice variation in management due to differences in guidelines and their usage and adherence. We aimed to assess whether management in febrile children below 3 months attending European Emergency Departments (EDs) was according to the guidelines for fever. This study is part of the MOFICHE study, which is an observational multicenter study including routine data of febrile children (0–18 years) attending twelve EDs in eight European countries. In febrile children below 3 months (excluding bronchiolitis), we analyzed actual management compared to the guidelines for fever. Ten EDs applied the (adapted) NICE guideline, and two EDs applied local guidelines. Management included diagnostic tests, antibiotic treatment, and admission. We included 913 children with a median age of 1.7 months (IQR 1.0–2.3). Management per ED varied as follows: use of diagnostic tests 14–83%, antibiotic treatment 23–54%, admission 34–86%. Adherence to the guideline was 43% (374/868) for blood cultures, 29% (144/491) for lumbar punctures, 55% (270/492) for antibiotic prescriptions, and 67% (573/859) for admission. Full adherence to these four management components occurred in 15% (132/868, range 0–38%), partial adherence occurred in 56% (484/868, range 35–77%). Conclusion: There is large practice variation in management. The guideline adherence was limited, but highest for admission which implies a cautious approach. Future studies should focus on guideline revision including new biomarkers in order to optimize management in young febrile children.What is Known:• Febrile children below 3 months have a higher risk of serious bacterial infections, which often leads to extensive diagnostics and treatment.• There is practice variation in management of young febrile children due to differences in guidelines and their usage and adherence.What is New:• Full guideline adherence is limited, whereas partial guideline adherence is moderate in febrile children below 3 months across Europe.• Guideline revision including new biomarkers is needed to improve management in young febrile children.Peer reviewe
Emergency medical services utilisation among febrile children attending emergency departments across Europe : an observational multicentre study
Get PDFFunding Information: This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 848196. CT received an additional funding from Stichting Erasmus Trustfonds. The Research was supported by the National Institute for Health Research Biomedical Research Centres at Imperial College London, Newcastle Hospitals NHS Foundation Trust, and Newcastle University. The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR, or the Department of Health. For the remaining authors, no sources of funding were declared. The funding sources had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication. Publisher Copyright: © 2023, The Author(s).Children constitute 6–10% of all patients attending the emergency department (ED) by emergency medical services (EMS). However, discordant EMS use in children occurs in 37–61% with fever as an important risk factor. We aimed to describe EMS utilisation among febrile children attending European EDs. This study is part of an observational multicentre study assessing management and outcome in febrile children up to 18 years (MOFICHE) attending twelve EDs in eight European countries. Discordant EMS use was defined as the absence of markers of urgency including intermediate/high triage urgency, advanced diagnostics, treatment, and admission in children transferred by EMS. Multivariable logistic regression analyses were performed for the association between (1) EMS use and markers of urgency, and (2) patient characteristics and discordant EMS use after adjusting all analyses for the covariates age, gender, visiting hours, presenting symptoms, and ED setting. A total of 5464 (15%, range 0.1–42%) children attended the ED by EMS. Markers of urgency were more frequently present in the EMS group compared with the non-EMS group. Discordant EMS use occurred in 1601 children (29%, range 1–59%). Age and gender were not associated with discordant EMS use, whereas neurological symptoms were associated with less discordant EMS use (aOR 0.2, 95%CI 0.1–0.2), and attendance out of office hours was associated with more discordant EMS use (aOR 1.6, 95%CI 1.4–1.9). Settings with higher percentage of self-referrals to the ED had more discordant EMS use (p < 0.05). Conclusion: There is large practice variation in EMS use in febrile children attending European EDs. Markers of urgency were more frequently present in children in the EMS group. However, discordant EMS use occurred in 29%. Further research is needed on non-medical factors influencing discordant EMS use in febrile children across Europe, so that pre-emptive strategies can be implemented. What is Known: •Children constitute around 6–10% of all patients attending the emergency department by emergency medical services. •Discordant EMS use occurs in 37–61% of all children, with fever as most common presenting symptom for discordant EMS use in children. What is New: •There is large practice variation in EMS use among febrile children across Europe with discordance EMS use occurring in 29% (range 1–59%), which was associated with attendance during out of office hours and with settings with higher percentage of self-referrals to the ED. •Future research is needed focusing on non-medical factors (socioeconomic status, parental preferences and past experience, healthcare systems, referral pathways, out of hours services provision) that influence discordant EMS use in febrile children across Europe.Peer reviewe
Febrile illness in high-risk children : a prospective, international observational study
Get PDFFunding Information: This project received funding under the European Union’s Horizon2020 research and innovation programme, grant agreement number 668303. UK enrolment was supported by NIHR Biomedical Research Centres at Imperial College London, and Newcastle. Publisher Copyright: © 2022, The Author(s).To assess and describe the aetiology and management of febrile illness in children with primary or acquired immunodeficiency at high risk of serious bacterial infection, as seen in emergency departments in tertiary hospitals. Prospective data on demographics, presenting features, investigations, microbiology, management, and outcome of patients within the ‘Biomarker Validation in HR patients’ database in PERFORM, were analysed. Immunocompromised children (< 18 years old) presented to fifteen European hospitals in nine countries, and one Gambian hospital, with fever or suspected infection and clinical indication for blood investigations. Febrile episodes were assigned clinical phenotypes using the validated PERFORM algorithm. Logistic regression was used to assess the effect size of predictive features of proven/presumed bacterial or viral infection. A total of 599 episodes in 482 children were analysed. Seventy-eight episodes (13.0%) were definite bacterial, 67 episodes probable bacterial (11.2%), and 29 bacterial syndrome (4.8%). Fifty-five were definite viral (9.2%), 49 probable viral (8.2%), and 23 viral syndrome (3.8%). One hundred ninety were unknown bacterial or viral infections (31.7%), and 108 had inflammatory or other non-infectious causes of fever (18.1%). Predictive features of proven/presumed bacterial infection were ill appearance (OR 3.1 (95% CI 2.1–4.6)) and HIV (OR 10.4 (95% CI 2.0–54.4)). Ill appearance reduced the odds of having a proven/presumed viral infection (OR 0.5 (95% CI 0.3–0.9)). A total of 82.1% had new empirical antibiotics started on admission (N = 492); 94.3% proven/presumed bacterial (N = 164), 66.1% proven/presumed viral (N = 84), and 93.2% unknown bacterial or viral infections (N = 177). Mortality was 1.9% (N = 11) and 87.1% made full recovery (N = 522). Conclusion: The aetiology of febrile illness in immunocompromised children is diverse. In one-third of cases, no cause for the fever will be identified. Justification for standard intravenous antibiotic treatment for every febrile immunocompromised child is debatable, yet effective. Better clinical decision-making tools and new biomarkers are needed for this population.What is Known:• Immunosuppressed children are at high risk for morbidity and mortality of serious bacterial and viral infection, but often present with fever as only clinical symptom.• Current diagnostic measures in this group are not specific to rule out bacterial infection, and positivity rates of microbiological cultures are low.What is New:• Febrile illness and infectious complications remain a significant cause of mortality and morbidity in HR children, yet management is effective.• The aetiology of febrile illness in immunocompromised children is diverse, and development of pathways for early discharge or cessation of intravenous antibiotics is debatable, and requires better clinical decision-making tools and biomarkers.Peer reviewe
Genomic investigations of unexplained acute hepatitis in children
Get PDFFunding Information: UKHSA funded the metagenomics and HAdV sequencing. We thank A. Nathwani for helpful discussions. We acknowledge the considerable contribution from the GOSH microbiology laboratory. We thank the medical students who contributed to the DIAMOND consortium. All research at GOSH and UCL GOSH Institute of Child Health is made possible by the NIHR GOSH Biomedical Research Centre. The views expressed are those of the authors and not necessarily those of the NHS, the National Institute for Health Research (NIHR), the UKRI or the Department of Health and Social Care. The work was part funded by the NIHR Blood and Transplant Research Unit in Genomics to Enhance Microbiology Screening (GEMS), the National Institute for Health and Care Research (CO-CIN-01) or jointly by NIHR and UK Research and Innovation (CV220-169, MC_PC_19059). S. Morfopoulou is funded by a W.T. Henry Wellcome fellowship (206478/Z/17/Z). S.B. and O.E.T.M. are funded by the NIHR Blood and Transplant Research Unit (GEMS). M.M.M. and M.L. are supported in part by the NIHR Biomedical Research Centre of Imperial College NHS Trust. J.B. receives NIHR Senior Investigator Funding. M.N. and J.B. are supported by the Wellcome Trust (207511/Z/17/Z and 203268/Z/16/Z). M.N., J.B. and G.P. are supported by the NIHR University College London Hospitals Biomedical Research Centre. P. Simmonds is supported by the NIHR (NIHR203338). T.S.J. is grateful for funding from the Brain Tumour Charity, Children with Cancer UK, GOSH Children’s Charity, Olivia Hodson Cancer Fund, Cancer Research UK and the NIHR. DIAMONDS is funded by the European Union (Horizon 2020; grant 848196). PERFORM was funded by the European Union (Horizon 2020; grant 668303). Publisher Copyright: © 2023, The Author(s).Since its first identification in Scotland, over 1,000 cases of unexplained paediatric hepatitis in children have been reported worldwide, including 278 cases in the UK1. Here we report an investigation of 38 cases, 66 age-matched immunocompetent controls and 21 immunocompromised comparator participants, using a combination of genomic, transcriptomic, proteomic and immunohistochemical methods. We detected high levels of adeno-associated virus 2 (AAV2) DNA in the liver, blood, plasma or stool from 27 of 28 cases. We found low levels of adenovirus (HAdV) and human herpesvirus 6B (HHV-6B) in 23 of 31 and 16 of 23, respectively, of the cases tested. By contrast, AAV2 was infrequently detected and at low titre in the blood or the liver from control children with HAdV, even when profoundly immunosuppressed. AAV2, HAdV and HHV-6 phylogeny excluded the emergence of novel strains in cases. Histological analyses of explanted livers showed enrichment for T cells and B lineage cells. Proteomic comparison of liver tissue from cases and healthy controls identified increased expression of HLA class 2, immunoglobulin variable regions and complement proteins. HAdV and AAV2 proteins were not detected in the livers. Instead, we identified AAV2 DNA complexes reflecting both HAdV-mediated and HHV-6B-mediated replication. We hypothesize that high levels of abnormal AAV2 replication products aided by HAdV and, in severe cases, HHV-6B may have triggered immune-mediated hepatic disease in genetically and immunologically predisposed children.Peer reviewe
