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1.
Childs Nerv Syst ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858274

RESUMO

PURPOSE: Brain Injury Guidelines (BIG) have been established to guide management related to TBI in adults. Here, BIG criteria were applied to pediatric TBI patients to evaluate reliability, safety, and resource utilization. METHODS: A retrospective study was performed on all pediatric TBI patients aged 18 years or younger from January 2012 to July 2023 at a Level 1 Pediatric Trauma Center. The severity of TBI (BIG 1/2/3) was rated by review of initial cranial imaging by two independent observers. Inter-observer reliability was assessed. Predictions based on BIG criteria regarding repeat cranial imaging, ICU admission, and neurosurgical consultation were compared with observations from the cohort. Outcome data was collected, including neurosurgical intervention and mortality rate. RESULTS: Three hundred fifty-nine patients were included with mean age of 5.3 years. Injury severity included 44 BIG 1 (12.2%), 170 BIG 2 (47.4%), and 145 BIG 3 injuries (40.4%). Inter-rater reliability was 96.4%. Neurosurgical consultation was obtained in all patients, though only predicted by guidelines in 40.4%. Repeat imaging was obtained in 166 BIG 1/2 patients, with an average of 1.3 CT scans and 0.8 MRIs/rapid MRIs per patient. ICU was utilized in 104 (77.6%) patients not recommended per BIG criteria. Ultimately, 37 patients, all BIG 3, required neurosurgical intervention; no neurosurgical interventions were required in those classified as BIG 1/2. CONCLUSIONS: BIG criteria can be applied to pediatric TBI with high inter-observer reliability and without formal neurosurgical training. Retrospective application of BIG predicted fewer imaging studies, ICU admissions, and neurosurgical consults without overlooking patients requiring neurosurgical intervention.

2.
Transplant Cell Ther ; 30(7): 727.e1-727.e8, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38710302

RESUMO

Outcomes for adults with relapsed/refractory (R/R) high-grade myeloid neoplasms remain poor, with allogeneic hematopoietic cell transplantation (HCT) the sole therapy likely to result in cure. We conducted the present study to determine the feasibility of early HCT-within 60 days of beginning reinduction chemotherapy-to see whether getting patients to HCT in an expeditious manner would expand the number of patients being offered this curative option. In this proof-of-principle feasibility study, we included adults age 18 to 75 years with R/R myeloid malignancies with ≥10% blood/marrow blasts at diagnosis who were eligible for a reduced-intensity HCT. Subjects received reinduction chemotherapy with cladribine, cytarabine, mitoxantrone, and filgrastim (CLAG-M) and proceeded to HCT with reduced-intensity conditioning (fludarabine/ melphalan). We enrolled 30 subjects, all of whom received CLAG-M reinduction, although only 9 underwent HCT within 60 days (<15, the predetermined threshold for feasibility "success"), with a median time to HCT of 48 days (range, 42 to 60 days). Eleven additional subjects received HCT beyond the target 60 days (off-study), with a median time to transplantation of 83 days (range, 53 to 367 days). Barriers to early HCT included infection, physician preference, lack of an HLA-matched donor, logistical delays, and disease progression, all of which may limit the real-world uptake of such early-to-transplantation protocols.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Transplante Homólogo , Humanos , Transplante de Células-Tronco Hematopoéticas/métodos , Pessoa de Meia-Idade , Masculino , Adulto , Feminino , Idoso , Condicionamento Pré-Transplante/métodos , Citarabina/uso terapêutico , Citarabina/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Estudos de Viabilidade , Adulto Jovem , Cladribina/uso terapêutico , Cladribina/administração & dosagem , Mitoxantrona/uso terapêutico , Mitoxantrona/administração & dosagem , Recidiva , Adolescente
3.
R Soc Open Sci ; 11(5): 231846, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38716330

RESUMO

In this work, we have carried out a comprehensive characterization of the vibrational spectroscopy of the non-planar molecule thianthrene. The combination of infrared, Raman and inelastic neutron scattering spectroscopies is highly complementary and allows all of the modes to be observed. Periodic density-functional theory calculations have provided unambiguous assignments of the spectra. The literature states that C-S stretch modes occur in the 600-800 cm-1 range. We find that while there are modes that involve sulfur motion in this region, this is a consequence of motion in the ortho-phenylene rings. The modes that are driven by the C-S stretches are found in the ~400-500 cm-1 range. The C-S-C bending modes occur in the 200-300 cm-1 range; these have not been previously characterized.

4.
Metabolomics ; 20(3): 56, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38762675

RESUMO

INTRODUCTION: Preeclampsia (PreE) remains a major source of maternal and newborn complications. Prenatal prediction of these complications could significantly improve pregnancy management. OBJECTIVES: Using metabolomic analysis we investigated the prenatal prediction of maternal and newborn complications in early and late PreE and investigated the pathogenesis of such complications. METHODS: Serum samples from 76 cases of PreE (36 early-onset and 40 late-onset), and 40 unaffected controls were collected. Direct Injection Liquid Chromatography-Mass Spectrometry combined with Nuclear Magnetic Resonance (NMR) spectroscopy was performed. Logistic regression analysis was used to generate models for prediction of adverse maternal and neonatal outcomes in patients with PreE. Metabolite set enrichment analysis (MSEA) was used to identify the most dysregulated metabolites and pathways in PreE. RESULTS: Forty-three metabolites were significantly altered (p < 0.05) in PreE cases with maternal complications and 162 metabolites were altered in PreE cases with newborn adverse outcomes. The top metabolite prediction model achieved an area under the receiver operating characteristic curve (AUC) = 0.806 (0.660-0.952) for predicting adverse maternal outcomes in early-onset PreE, while the AUC for late-onset PreE was 0.843 (0.712-0.974). For the prediction of adverse newborn outcomes, regression models achieved an AUC = 0.828 (0.674-0.982) in early-onset PreE and 0.911 (0.828-0.994) in late-onset PreE. Profound alterations of lipid metabolism were associated with adverse outcomes. CONCLUSION: Prenatal metabolomic markers achieved robust prediction, superior to conventional markers for the prediction of adverse maternal and newborn outcomes in patients with PreE. We report for the first-time the prediction and metabolomic basis of adverse maternal and newborn outcomes in patients with PreE.


Assuntos
Metabolômica , Pré-Eclâmpsia , Humanos , Gravidez , Feminino , Pré-Eclâmpsia/metabolismo , Pré-Eclâmpsia/sangue , Metabolômica/métodos , Recém-Nascido , Adulto , Metaboloma , Estudos de Casos e Controles , Biomarcadores/sangue , Espectroscopia de Ressonância Magnética/métodos , Curva ROC
5.
Drug Discov Today ; 29(7): 104022, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38750927

RESUMO

Active pharmaceutical ingredients (APIs) in the environment, primarily resulting from patient excretion, are of concern because of potential risks to wildlife. This has led to more restrictive regulatory policies. Here, we discuss the 'benign-by-design' approach, which encourages the development of environmentally friendly APIs that are also safe and efficacious for patients. We explore the challenges and opportunities associated with identifying chemical properties that influence the environmental impact of APIs. Although a straightforward application of greener properties could hinder the development of new drugs, more nuanced approaches could lead to drugs that benefit both patients and the environment. We advocate for an enhanced dialogue between research and development (R&D) and environmental scientists and development of a toolbox to incorporate environmental sustainability in drug development.

6.
Nature ; 626(8000): 852-858, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38326608

RESUMO

Bile acids (BAs) are steroid detergents in bile that contribute to the absorption of fats and fat-soluble vitamins while shaping the gut microbiome because of their antimicrobial properties1-4. Here we identify the enzyme responsible for a mechanism of BA metabolism by the gut microbiota involving amino acid conjugation to the acyl-site of BAs, thus producing a diverse suite of microbially conjugated bile acids (MCBAs). We show that this transformation is mediated by acyltransferase activity of bile salt hydrolase (bile salt hydrolase/transferase, BSH/T). Clostridium perfringens BSH/T rapidly performed acyl transfer when provided various amino acids and taurocholate, glycocholate or cholate, with an optimum at pH 5.3. Amino acid conjugation by C. perfringens BSH/T was diverse, including all proteinaceous amino acids except proline and aspartate. MCBA production was widespread among gut bacteria, with strain-specific amino acid use. Species with similar BSH/T amino acid sequences had similar conjugation profiles and several bsh/t alleles correlated with increased conjugation diversity. Tertiary structure mapping of BSH/T followed by mutagenesis experiments showed that active site structure affects amino acid selectivity. These MCBA products had antimicrobial properties, where greater amino acid hydrophobicity showed greater antimicrobial activity. Inhibitory concentrations of MCBAs reached those measured natively in the mammalian gut. MCBAs fed to mice entered enterohepatic circulation, in which liver and gallbladder concentrations varied depending on the conjugated amino acid. Quantifying MCBAs in human faecal samples showed that they reach concentrations equal to or greater than secondary and primary BAs and were reduced after bariatric surgery, thus supporting MCBAs as a significant component of the BA pool that can be altered by changes in gastrointestinal physiology. In conclusion, the inherent acyltransferase activity of BSH/T greatly diversifies BA chemistry, creating a set of previously underappreciated metabolites with the potential to affect the microbiome and human health.


Assuntos
Aciltransferases , Amidoidrolases , Ácidos e Sais Biliares , Clostridium perfringens , Microbioma Gastrointestinal , Animais , Humanos , Camundongos , Aciltransferases/química , Aciltransferases/metabolismo , Alelos , Amidoidrolases/química , Amidoidrolases/metabolismo , Aminoácidos/metabolismo , Anti-Infecciosos/metabolismo , Anti-Infecciosos/farmacologia , Cirurgia Bariátrica , Ácidos e Sais Biliares/química , Ácidos e Sais Biliares/metabolismo , Domínio Catalítico , Clostridium perfringens/enzimologia , Clostridium perfringens/metabolismo , Fezes/química , Vesícula Biliar/metabolismo , Microbioma Gastrointestinal/fisiologia , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Fígado/metabolismo , Ácido Taurocólico/metabolismo
7.
Environ Toxicol Chem ; 43(3): 559-574, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36722131

RESUMO

In 2012, 20 key questions related to hazard and exposure assessment and environmental and health risks of pharmaceuticals and personal care products in the natural environment were identified. A decade later, this article examines the current level of knowledge around one of the lowest-ranking questions at that time, number 19: "Can nonanimal testing methods be developed that will provide equivalent or better hazard data compared with current in vivo methods?" The inclusion of alternative methods that replace, reduce, or refine animal testing within the regulatory context of risk and hazard assessment of chemicals generally faces many hurdles, although this varies both by organism (human-centric vs. other), sector, and geographical region or country. Focusing on the past 10 years, only works that might reasonably be considered to contribute to advancements in the field of aquatic environmental risk assessment are highlighted. Particular attention is paid to methods of contemporary interest and importance, representing progress in (1) the development of methods which provide equivalent or better data compared with current in vivo methods such as bioaccumulation, (2) weight of evidence, or (3) -omic-based applications. Evolution and convergence of these risk assessment areas offer the basis for fundamental frameshifts in how data are collated and used for the protection of taxa across the breadth of the aquatic environment. Looking to the future, we are at a tipping point, with a need for a global and inclusive approach to establish consensus. Bringing together these methods (both new and old) for regulatory assessment and decision-making will require a concerted effort and orchestration. Environ Toxicol Chem 2024;43:559-574. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.


Assuntos
Ecotoxicologia , Meio Ambiente , Animais , Humanos , Ecotoxicologia/métodos , Medição de Risco/métodos
8.
Environ Toxicol Chem ; 43(3): 513-525, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37067359

RESUMO

The extrapolation of biological data across species is a key aspect of biomedical research and drug development. In this context, comparative biology considerations are applied with the goal of understanding human disease and guiding the development of effective and safe medicines. However, the widespread occurrence of pharmaceuticals in the environment and the need to assess the risk posed to wildlife have prompted a renewed interest in the extrapolation of pharmacological and toxicological data across the entire tree of life. To address this challenge, a biological "read-across" approach, based on the use of mammalian data to inform toxicity predictions in wildlife species, has been proposed as an effective way to streamline the environmental safety assessment of pharmaceuticals. Yet, how effective has this approach been, and are we any closer to being able to accurately predict environmental risk based on known human risk? We discuss the main theoretical and experimental advancements achieved in the last 10 years of research in this field. We propose that a better understanding of the functional conservation of drug targets across species and of the quantitative relationship between target modulation and adverse effects should be considered as future research priorities. This pharmacodynamic focus should be complemented with the application of higher-throughput experimental and computational approaches to accelerate the prediction of internal exposure dynamics. The translation of comparative (eco)toxicology research into real-world applications, however, relies on the (limited) availability of experts with the skill set needed to navigate the complexity of the problem; hence, we also call for synergistic multistakeholder efforts to support and strengthen comparative toxicology research and education at a global level. Environ Toxicol Chem 2024;43:513-525. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.


Assuntos
Ecotoxicologia , Mamíferos , Animais , Humanos , Medição de Risco/métodos , Ecotoxicologia/métodos , Preparações Farmacêuticas
9.
Environ Toxicol Chem ; 43(3): 526-536, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37787405

RESUMO

Translation of environmental science to the practice aims to protect biodiversity and ecosystem services, and our future ability to do so relies on the development of a precision ecotoxicology approach wherein we leverage the genetics and informatics of species to better understand and manage the risks of global pollution. A little over a decade ago, a workshop focusing on the risks of pharmaceuticals and personal care products (PPCPs) in the environment identified a priority research question, "What can be learned about the evolutionary conservation of PPCP targets across species and life stages in the context of potential adverse outcomes and effects?" We review the activities in this area over the past decade, consider prospects of more recent developments, and identify future research needs to develop next-generation approaches for PPCPs and other global chemicals and waste challenges. Environ Toxicol Chem 2024;43:526-536. © 2023 SETAC. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.


Assuntos
Cosméticos , Poluentes Químicos da Água , Humanos , Ecotoxicologia , Ecossistema , Monitoramento Ambiental , Medição de Risco , Cosméticos/toxicidade , Cosméticos/análise , Preparações Farmacêuticas , Poluentes Químicos da Água/análise
10.
Metabolomics ; 20(1): 3, 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38066384

RESUMO

INTRODUCTION: Consumption of a Mediterranean diet (MD) has established health benefits, and the identification of novel biomarkers could enable objective monitoring of dietary pattern adherence. OBJECTIVES: The present investigation performed untargeted metabolomics on blood plasma from a controlled study of MD adherence, to identify novel blood-based metabolite biomarkers associated with the MD pattern, and to build a logistic regression model that could be used to characterise MD adherence. METHODS: A hundred and thirty-five plasma samples from n = 58 patients collected at different time points were available. Using a 14-point scale MD Score (MDS) subjects were divided into 'high' or 'low' MDS adherence groups and liquid chromatography-mass spectrometry (LC-MS/MS) was applied for analysis. RESULTS: The strongest association with MDS was pectenotoxin 2 seco acid (r = 0.53; ROC = 0.78), a non-toxic marine xenobiotic metabolite. Several lipids were useful biomarkers including eicosapentaenoic acid, the structurally related lysophospholipid (20:5(5Z,8Z,11Z,14Z,17Z)/0:0), a phosphatidylcholine (P-18:1(9Z)/16:0) and also xi-8-hydroxyhexadecanedioic acid. Two metabolites negatively correlated with MDS, these were the monoacylglycerides (0:0/16:1(9Z)/0:0) and (0:0/20:3(5Z,8Z,11Z)/0:0). By stepwise elimination we selected a panel of 3 highly discriminatory metabolites and developed a linear regression model which identified 'high MDS' individuals with high sensitivity and specificity [AUC (95% CI) 0.83 (0.76-0.97)]. CONCLUSION: Our study highlights the utility of metabolomics as an approach for developing novel panels of dietary biomarkers. Quantitative profiling of these metabolites is required to validate their utility for evaluating dietary adherence.


Assuntos
Dieta Mediterrânea , Metabolômica , Humanos , Metabolômica/métodos , Cromatografia Líquida , Espectrometria de Massas em Tandem , Biomarcadores , Plasma
11.
Int J Mol Sci ; 24(23)2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-38068957

RESUMO

In this work, a computational spectroscopy approach was used to provide a complete assignment of the inelastic neutron scattering spectra of three title alkoxysilane derivatives-3-aminopropyltrimethoxysilane (APTS), N-methyl-3-aminopropyltrimethoxysilane (MAPTS), and 3-aminopropyltriethoxysilane (APTES). The simulated spectra obtained from density functional theory (DFT) calculations exhibit a remarkable match with the experimental spectra. The description of the experimental band profiles improves as the number of molecules considered in the theoretical model increases, from monomers to trimers. This highlights the significance of incorporating non-covalent interactions, encompassing classical NH···N, N-H···O, as well as C-H···N and C-H···O hydrogen bond contacts, to achieve a comprehensive understanding of the system. A distinct scenario emerges when considering optical vibrational techniques, infrared and Raman spectroscopy. In these instances, the monomer model provides a reasonable description of the experimental spectra, and no substantial alterations are observed in the simulated spectra when employing dimer and trimer models. This observation underscores the distinctive ability of neutron spectroscopy in combination with DFT calculations in assessing the structure and dynamics of molecular materials.


Assuntos
Análise Espectral Raman , Modelos Moleculares , Análise Espectral Raman/métodos , Espectroscopia de Infravermelho com Transformada de Fourier
12.
Sci Rep ; 13(1): 22260, 2023 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-38097614

RESUMO

Traumatic brain injury (TBI) is a major cause of mortality and disability worldwide, particularly among individuals under the age of 45. It is a complex, and heterogeneous disease with a multifaceted pathophysiology that remains to be elucidated. Metabolomics has the potential to identify metabolic pathways and unique biochemical profiles associated with TBI. Herein, we employed a longitudinal metabolomics approach to study TBI in a weight drop mouse model to reveal metabolic changes associated with TBI pathogenesis, severity, and secondary injury. Using proton nuclear magnetic resonance (1H NMR) spectroscopy, we biochemically profiled post-mortem brain from mice that suffered mild TBI (N = 25; 13 male and 12 female), severe TBI (N = 24; 11 male and 13 female) and sham controls (N = 16; 11 male and 5 female) at baseline, day 1 and day 7 following the injury. 1H NMR-based metabolomics, in combination with bioinformatic analyses, highlights a few significant metabolites associated with TBI severity and perturbed metabolism related to the injury. We report that the concentrations of taurine, creatinine, adenine, dimethylamine, histidine, N-Acetyl aspartate, and glucose 1-phosphate are all associated with TBI severity. Longitudinal metabolic observation of brain tissue revealed that mild TBI and severe TBI lead distinct metabolic profile changes. A multi-class model was able to classify the severity of injury as well as time after TBI with estimated 86% accuracy. Further, we identified a high degree of correlation between respective hemisphere metabolic profiles (r > 0.84, p < 0.05, Pearson correlation). This study highlights the metabolic changes associated with underlying TBI severity and secondary injury. While comprehensive, future studies should investigate whether: (a) the biochemical pathways highlighted here are recapitulated in the brain of TBI sufferers and (b) if the panel of biomarkers are also as effective in less invasively harvested biomatrices, for objective and rapid identification of TBI severity and prognosis.


Assuntos
Concussão Encefálica , Lesões Encefálicas Traumáticas , Masculino , Feminino , Camundongos , Animais , Lesões Encefálicas Traumáticas/metabolismo , Encéfalo/metabolismo , Metabolômica/métodos , Metaboloma , Prognóstico , Concussão Encefálica/complicações
13.
Metabolites ; 13(12)2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38132886

RESUMO

Huntington's disease (HD) is a progressive, fatal neurodegenerative disease characterized by motor, cognitive, and psychiatric symptoms. The precise mechanisms of HD progression are poorly understood; however, it is known that there is an expansion of the trinucleotide cytosine-adenine-guanine (CAG) repeat in the Huntingtin gene. Important new strategies are of paramount importance to identify early biomarkers with predictive value for intervening in disease progression at a stage when cellular dysfunction has not progressed irreversibly. Metabolomics is the study of global metabolite profiles in a system (cell, tissue, or organism) under certain conditions and is becoming an essential tool for the systemic characterization of metabolites to provide a snapshot of the functional and pathophysiological states of an organism and support disease diagnosis and biomarker discovery. This review briefly highlights the historical progress of metabolomic methodologies, followed by a more detailed review of the use of metabolomics in HD research to enable a greater understanding of the pathogenesis, its early prediction, and finally the main technical platforms in the field of metabolomics.

14.
Chem Commun (Camb) ; 59(85): 12767-12770, 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37812072

RESUMO

We use in situ neutron imaging to observe the adsorption/absorption of hydrogen within a packed catalyst bed of a Pd/C catalyst at a spatial and temporal resolution of ∼430 µm and a ∼9 s respectively. Additionally, the H2/D2 exchange process across the catalyst bed is followed in real time.

15.
Pediatr Dev Pathol ; 26(5): 429-436, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37672676

RESUMO

Uterine involution has 2 major components-(1) involution of vessels; and (2) involution of myometrium. Involution of vessels was addressed by Rutherford and Hertig in 1945; however, involution of myometrium has received little attention in the modern literature. We suggest that the pathophysiology of myometrial involution may lead to uterine atony and postpartum hemorrhage. The myometrium dramatically enlarges due to gestational hyperplasia and hypertrophy of myocytes, caused by hormonal influences of the fetal adrenal cortex and the placenta. After delivery, uterine weight drops rapidly, with physiologic involution of myometrium associated with massive destruction of myometrial tissue. The resulting histopathology, supported by scientific evidence, may be termed "postpartum metropathy," and may explain the delay of postpartum menstrual periods until the completion of involution. When uterine atony causes uncontrolled hemorrhage, postpartum hysterectomy examination may be the responsibility of the perinatal pathologist.Postpartum metropathy may be initiated when delivery of the baby terminates exposure to the hormonal influence of the fetal adrenal cortex, and may be accelerated when placental delivery terminates exposure to human chorionic gonadotrophin (HCG). This hypothesis may explain why a prolonged third stage of labor, and delays in management, are risk factors for severe hemorrhage due to uterine atony.


Assuntos
Hemorragia Pós-Parto , Inércia Uterina , Gravidez , Feminino , Humanos , Hemorragia Pós-Parto/etiologia , Hemorragia Pós-Parto/patologia , Inércia Uterina/patologia , Placenta , Miométrio/patologia
16.
Rev Sci Instrum ; 94(9)2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37724925

RESUMO

CO2 mineralization via aqueous Mg/Ca/Na-carbonate (MgCO3/CaCO3/Na2CO3) formation represents a huge opportunity for the utilization of captured CO2. However, large-scale mineralization is hindered by slow kinetics due to the highly hydrated character of the cations in aqueous solutions (Mg2+ in particular). Reaction conditions can be optimized to accelerate carbonation kinetics, for example, by the inclusion of additives that promote competitive dehydration of Mg2+ and subsequent agglomeration, nucleation, and crystallization. For tracking mineralization and these reaction steps, neutron scattering presents unprecedented advantages over traditional techniques for time-resolved in situ measurements. However, a setup providing continuous solution circulation to ensure reactant system homogeneity for industrially relevant CO2-mineralization is currently not available for use on neutron beamlines. We, therefore, undertook the design, construction, testing and implementation of such a self-contained reactor rig for use on selected neutron beamlines at the ISIS Neutron and Muon Source (Harwell, UK). The design ensured robust attachment via suspension from the covering Tomkinson flange to stabilize the reactor assembly and all fittings (~25 kg), as well as facilitating precise alignment of the entire reactor and sample (test) cell with respect to beam dimension and direction. The assembly successfully accomplished the principal tasks of providing a continuous flow of the reaction mixture (~500 mL) for homogeneity, quantitative control of CO2 flux into the mixture, and temperature and pressure regulation throughout the reaction and measurements. The design is discussed, with emphasis placed on the reactor, including its geometry, components, and all technical specifications. Descriptions of the off-beamline bench tests, safety, and functionality, as well as the installation on beamlines and trial experimental procedure, are provided, together with representative raw neutron scattering results.

17.
Phys Chem Chem Phys ; 25(38): 25993-26005, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37729436

RESUMO

As part of an on-going programme of development of an aniline synthesis catalyst suitable for operation at elevated temperatures, the geometry of the adsorption complex for nitrobenzene on a 5 wt% Pd/Al2O3 catalyst is investigated by infrared (IR) spectroscopy. Via an appreciation of the reduced site symmetry resulting from adsorption, application of the metal surface selection rule, and observation of in-plane modes only, the adsorption complex (Pd-nitrobenzene) at 28 °C is assigned as occurring vertically or tilted with respect to the metal surface, adopting Csσv(yz) symmetry. Moreover, adsorption occurs via a single Pd-O bond. Single molecule DFT calculations and simulated IR spectra assist vibrational assignments but indicate a parallel adsorption geometry to be energetically favourable. The contradiction between calculated and observed structures is attributed to the DFT calculations corresponding to an isolated molecule adsorption complex, while IR spectra relate to multi molecule adsorption that is encountered during sustained catalytic turnover. Residual hydrogen from the catalyst reduction stage leads to aniline formation on the Pd surface at low nitrobenzene coverages but, on increasing nitrobenzene exposure, the aniline is forced on to the alumina support. A reaction scheme is proposed whereby the nitrobenzene adsorption geometry is inherently linked to the high aniline selectivity observed for Pd/Al2O3 catalysts.

18.
Genes (Basel) ; 14(9)2023 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-37761892

RESUMO

The impact of environmental factors on epigenetic changes is well established, and cellular function is determined not only by the genome but also by interacting partners such as metabolites. Given the significant impact of metabolism on disease progression, exploring the interaction between the metabolome and epigenome may offer new insights into Huntington's disease (HD) diagnosis and treatment. Using fourteen post-mortem HD cases and fourteen control subjects, we performed metabolomic profiling of human postmortem brain tissue (striatum and frontal lobe), and we performed DNA methylome profiling using the same frontal lobe tissue. Along with finding several perturbed metabolites and differentially methylated loci, Aminoacyl-tRNA biosynthesis (adj p-value = 0.0098) was the most significantly perturbed metabolic pathway with which two CpGs of the SEPSECS gene were correlated. This study improves our understanding of molecular biomarker connections and, importantly, increases our knowledge of metabolic alterations driving HD progression.


Assuntos
Aminoacil-tRNA Sintetases , Doença de Huntington , Humanos , Encéfalo/metabolismo , Doença de Huntington/genética , Metaboloma , Metilação , RNA de Transferência/biossíntese , Aminoacil-tRNA Sintetases/genética
19.
Biol Reprod ; 109(4): 415-431, 2023 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-37540198

RESUMO

Endometrial inflammation is associated with reduced pregnancy per artificial insemination (AI) and increased pregnancy loss in cows. It was hypothesized that induced endometritis alters histotroph composition and induces inflammatory signatures on conceptus that compromise development. In Experiment 1, lactating cows were assigned to control (CON; n = 23) or to an intrauterine infusion of Escherichia coli and Trueperella pyogenes (ENDO; n = 34) to induce endometritis. Cows received AI 26 days after treatment, and the uterine fluid and conceptuses were collected on day 16 after AI. In Experiment 2, Holstein heifers were assigned to CON (n = 14) or ENDO (n = 14). An embryo was transferred on day 7 of the estrous cycle, and uterine fluid and conceptuses were recovered on day 16. Composition of histotroph and trophoblast and embryonic disc gene expression were assessed. Bacterial-induced endometritis in lactating cows altered histotroph composition and pathways linked to phospholipid synthesis, cellular energy production, and the Warburg effect. Also, ENDO reduced conceptus length in cows and altered expression of genes involved in pathogen recognition, nutrient uptake, cell growth, choline metabolism, and conceptus signaling needed for maternal recognition of pregnancy. The impact of ENDO was lesser on conceptuses from heifers receiving embryo transfer; however, the affected genes and associated pathways involved restricted growth and increased immune response similar to the observed responses to ENDO in conceptuses from lactating cows. Bacterial-induced endometrial inflammation altered histotroph composition, reduced conceptus growth, and caused embryonic cells to activate survival rather than anabolic pathways that could compromise development.


Assuntos
Endometrite , Doenças Uterinas , Gravidez , Humanos , Bovinos , Animais , Feminino , Endometrite/veterinária , Lactação/fisiologia , Inseminação Artificial/veterinária , Inflamação
20.
J Alzheimers Dis Rep ; 7(1): 649-657, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37483327

RESUMO

Background: Alzheimer's disease (AD) is the most common form of dementia, accounting for 80% of all cases. Mild cognitive impairment (MCI) is a transitional state between normal aging and AD. Early detection is crucial, as irreversible brain damage occurs before symptoms manifest. Objective: This study aimed to identify potential biomarkers for early detection of AD by analyzing urinary cytokine concentrations. We investigated 37 cytokines in AD, MCI, and cognitively normal individuals (NC), assessing their associations with AD development. Methods: Urinary cytokine concentrations were measured in AD (n = 25), MCI (n = 25), and NC (n = 26) patients. IL6ST and MMP-2 levels were compared between AD and NC, while TNFRSF8, IL6ST, and IL-19 were assessed in AD versus MCI. Diagnostic models distinguished AD from NC, and in-silico analysis explored molecular mechanisms related to AD. Results: Significant perturbations in IL6ST and MMP-2 concentrations were observed in AD urine compared to NC, suggesting their potential as biomarkers. TNFRSF8, IL6ST, and IL-19 differed significantly between AD and MCI, implicating them in disease progression. Diagnostic models exhibited promising performance (AUC: 0.59-0.79, sensitivity: 0.72-0.80, specificity: 0.56-0.78) in distinguishing AD from NC. In-silico analysis revealed molecular insights, including relevant non-coding RNAs, microRNAs, and transcription factors. Conclusion: This study establishes significant associations between urinary cytokine concentrations and AD and MCI. IL6ST, MMP-2, TNFRSF8, IL6ST, and IL-19 emerge as potential biomarkers for early detection of AD. In-silico analysis enhances understanding of molecular mechanisms in AD. Further validation and exploration of these biomarkers in larger cohorts are warranted to assess their clinical utility.

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