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1.
BMJ Open ; 14(6): e083635, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38951004

RESUMO

INTRODUCTION: Critically ill patients are at risk of suboptimal beta-lactam antibiotic (beta-lactam) exposure due to the impact of altered physiology on pharmacokinetics. Suboptimal concentrations can lead to treatment failure or toxicity. Therapeutic drug monitoring (TDM) involves adjusting doses based on measured plasma concentrations and individualising dosing to improve the likelihood of improving exposure. Despite its potential benefits, its adoption has been slow, and data on implementation, dose adaptation and safety are sparse. The aim of this trial is to assess the feasibility and fidelity of implementing beta-lactam TDM-guided dosing in the intensive care unit setting. METHODS AND ANALYSIS: A beta-lactam antibiotic Dose AdaPtation feasibility randomised controlled Trial using Therapeutic Drug Monitoring (ADAPT-TDM) is a single-centre, unblinded, feasibility randomised controlled trial aiming to enroll up to 60 critically ill adult participants (≥18 years). TDM and dose adjustment will be performed daily in the intervention group; the standard of care group will undergo plasma sampling, but no dose adjustment. The main outcomes include: (1) feasibility of recruitment, defined as the number of participants who are recruited from a pool of eligible participants, and (2) fidelity of TDM, defined as the degree to which TDM as a test is delivered as intended, from accurate sample collection, sample processing to result availability. Secondary outcomes include target attainment, uptake of TDM-guided dosing and incidence of neurotoxicity, hepatotoxicity and nephrotoxicity. ETHICS AND DISSEMINATION: This study has been approved by the Alfred Hospital human research ethics committee, Office of Ethics and Research Governance (reference: Project No. 565/22; date of approval: 22/11/2022). Prospective consent will be obtained and the study will be conducted in accordance with the Declaration of Helsinki. The finalised manuscript, including aggregate data, will be submitted for publication in a peer reviewed journal. ADAPT-TDM will determine whether beta-lactam TDM-guided dose adaptation is reproducible and feasible and provide important information required to implement this intervention in a phase III trial. TRIAL REGISTRATION NUMBER: Australian New Zealand Clinical Trials Registry, ACTRN12623000032651.


Assuntos
Antibacterianos , Estado Terminal , Monitoramento de Medicamentos , Estudos de Viabilidade , beta-Lactamas , Humanos , Monitoramento de Medicamentos/métodos , Antibacterianos/administração & dosagem , Antibacterianos/farmacocinética , Estado Terminal/terapia , beta-Lactamas/administração & dosagem , beta-Lactamas/farmacocinética , Ensaios Clínicos Controlados Aleatórios como Assunto , Unidades de Terapia Intensiva
2.
ACS Chem Biol ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38912881

RESUMO

Eliminating the core fucose from the N-glycans of the Fc antibody segment by pathway engineering or enzymatic methods has been shown to enhance the potency of therapeutic antibodies, especially in the context of antibody-dependent cytotoxicity (ADCC). However, there is a significant challenge due to the limited defucosylation efficiency of commercially available α-l-fucosidases. In this study, we report a unique α-l-fucosidase (PnfucA) from the bacterium Prevotella nigrescens that has a low sequence identity compared with all other known α-l-fucosidases and is highly reactive toward a core disaccharide substrate with fucose α(1,3)-, α (1,4)-and α(1,6)-linked to GlcNAc, and is less reactive toward the Fuc-α(1,2)-Gal on the terminal trisaccharide of the oligosaccharide Globo H (Bb3). The kinetic properties of the enzyme, such as its Km and kcat, were determined and the optimized expression of PnfucA gave a yield exceeding 30 mg/L. The recombinant enzyme retained its full activity even after being incubated for 6 h at 37 °C. Moreover, it retained 92 and 87% of its activity after freezing and freeze-drying treatments, respectively, for over 28 days. In a representative glycoengineering of adalimumab (Humira), PnfucA showed remarkable hydrolytic efficiency in cleaving the α(1,6)-linked core fucose from FucGlcNAc on the antibody with a quantitative yield. This enabled the seamless incorporation of biantennary sialylglycans by Endo-S2 D184 M in a one-pot fashion to yield adalimumab in a homogeneous afucosylated glycoform with an improved binding affinity toward Fcγ receptor IIIa.

3.
Biochemistry ; 63(9): 1194-1205, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38598309

RESUMO

Barley (1,3;1,4)-ß-d-glucanase is believed to have evolved from an ancestral monocotyledon (1,3)-ß-d-glucanase, enabling the hydrolysis of (1,3;1,4)-ß-d-glucans in the cell walls of leaves and germinating grains. In the present study, we investigated the substrate specificities of variants of the barley enzymes (1,3;1,4)-ß-d-glucan endohydrolase [(1,3;1,4)-ß-d-glucanase] isoenzyme EII (HvEII) and (1,3)-ß-d-glucan endohydrolase [(1,3)-ß-d-glucanase] isoenzyme GII (HvGII) obtained by protein segment hybridization and site-directed mutagenesis. Using protein segment hybridization, we obtained three variants of HvEII in which the substrate specificity was that of a (1,3)-ß-d-glucanase and one variant that hydrolyzed both (1,3)-ß-d-glucans and (1,3;1,4)-ß-d-glucans; the wild-type enzyme hydrolyzed only (1,3;1,4)-ß-d-glucans. Using substitutions of specific amino acid residues, we obtained one variant of HvEII that hydrolyzed both substrates. However, neither protein segment hybridization nor substitutions of specific amino acid residues gave variants of HvGII that could hydrolyze (1,3;1,4)-ß-d-glucans; the wild-type enzyme hydrolyzed only (1,3)-ß-d-glucans. Other HvEII and HvGII variants showed changes in specific activity and their ability to degrade the (1,3;1,4)-ß-d-glucans or (1,3)-ß-d-glucans to larger oligosaccharides. We also used molecular dynamics simulations to identify amino-acid residues or structural regions of wild-type HvEII and HvGII that interact with (1,3;1,4)-ß-d-glucans and (1,3)-ß-d-glucans, respectively, and may be responsible for the substrate specificities of the two enzymes.


Assuntos
Hordeum , Hordeum/enzimologia , Hordeum/genética , Especificidade por Substrato , Mutagênese Sítio-Dirigida , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/química , Glucanos/metabolismo , Isoenzimas/genética , Isoenzimas/metabolismo , Isoenzimas/química , Mutagênese , beta-Glucanas/metabolismo
5.
Comput Softw Big Sci ; 7(1): 11, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37899771

RESUMO

We study the performance of a cloud-based GPU-accelerated inference server to speed up event reconstruction in neutrino data batch jobs. Using detector data from the ProtoDUNE experiment and employing the standard DUNE grid job submission tools, we attempt to reprocess the data by running several thousand concurrent grid jobs, a rate we expect to be typical of current and future neutrino physics experiments. We process most of the dataset with the GPU version of our processing algorithm and the remainder with the CPU version for timing comparisons. We find that a 100-GPU cloud-based server is able to easily meet the processing demand, and that using the GPU version of the event processing algorithm is two times faster than processing these data with the CPU version when comparing to the newest CPUs in our sample. The amount of data transferred to the inference server during the GPU runs can overwhelm even the highest-bandwidth network switches, however, unless care is taken to observe network facility limits or otherwise distribute the jobs to multiple sites. We discuss the lessons learned from this processing campaign and several avenues for future improvements.

6.
Health Justice ; 11(1): 29, 2023 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-37515602

RESUMO

BACKGROUND: Despite the heightened risk for substance use (SU) among youth in the juvenile justice system, many do not receive the treatment that they need. OBJECTIVES: The purpose of this study is to examine the extent to which youth under community supervision by juvenile justice agencies receive community-based SU services and the factors associated with access to such services. METHODS: Data are from a nationally representative sample of Community Supervision (CS) agencies and their primary behavioral health (BH) partners. Surveys were completed by 192 CS and 271 BH agencies. RESULTS: SU services are more often available through BH than CS for all treatment modalities. EBPs are more likely to be used by BH than by CS. Co-location of services occurs most often in communities with fewer treatment options and is associated with higher interagency collaboration. Youth are more likely to receive services in communities with higher EBP use, which mediates the relationship between the availability of SU treatment modalities and the proportion of youth served. CONCLUSION: Findings identify opportunities to strengthen community systems and improve linkage to care.

8.
Planta ; 257(2): 39, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36650257

RESUMO

MAIN CONCLUSION: The xyloglucans of all aquatic Araceae species examined had unusual structures compared with those of other non-commelinid monocotyledon families previously examined. The aquatic Araceae species Lemna minor was earlier shown to have xyloglucans with a different structure from the fucogalactoxyloglucans of other non-commelinid monocotyledons. We investigated 26 Araceae species (including L. minor), from five of the seven subfamilies. All seven aquatic species examined had xyloglucans that were unusual in having one or two of three features: < 77% XXXG core motif [L. minor (Lemnoideae) and Orontium aquaticum (Orontioideae)]; no fucosylation [L. minor (Lemnoideae), Cryptocoryne aponogetonifolia, and Lagenandra ovata (Aroideae, Rheophytes clade)]; and > 14% oligosaccharide units with S or D side chains [Spirodela polyrhiza and Landoltia punctata (Lemnoideae) and Pistia stratiotes (Aroideae, Dracunculus clade)]. Orontioideae and Lemnoideae are the two most basal subfamilies, with all species being aquatic, and Aroideae is the most derived. Two terrestrial species [Dieffenbachia seguine and Spathicarpa hastifolia (Aroideae, Zantedeschia clade)] also had xyloglucans without fucose indicating this feature was not unique to aquatic species.


Assuntos
Araceae , Glucanos , Xilanos , Oligossacarídeos
9.
Front Endocrinol (Lausanne) ; 13: 941832, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36387893

RESUMO

Lu-177 has been developed for the treatment of patients with peptide receptor radionuclide therapy (PRRT). A second generation pure no-carrier-added Lu-177 has a high specific activity and has waste disposal advantages over the first generation carrier-added Lu-177. PRRT has recently been developed for the treatment of neuroendocrine tumors (NETs). The majority of pancreatic and gastroenteric NETs (GEP-NETs) express the somatostatin receptors (SSTRs) 2 and 5. These receptors can be specifically targeted with a somatostatin peptide analogue (DOTATOC/DOTATATE) which can be chelated to a positron emission tomography (PET) emitting radioisotope such as Ga-68 for imaging or to a ß-emitting radioisotope Lu-177 for therapy. A key advantage of this approach is that the receptor expression can be demonstrated by PET imaging before the patient is treated. Clinical studies in G1 and G2 GEP-NETS have demonstrated that PRRT is extremely effective in terms of progression free survival (PFS), symptom control and quality of life, with a well-established safety profile. A beneficial effect on outcome survival awaits to be confirmed. The first commercially available product Lu-177-DOTATATE was approved following the NETTER-1 trial in G1 and G2 GE-NETS. Lu-177-DOTATATE 7,4 GBq every 8 weeks for 4 cycles, together with octreotide LAR 30 mg monthly, demonstrated a median PFS of 28,4 months compared to 8,5 months for octreotide LAR 60 mg monthly. A second pivotal study COMPETE is currently in progress, comparing no carrier-added (n.c.a.) Lu-177-DOTATOC to the m-TOR inhibitor Everolimus in both GE-NETs and PNETs. Two studies, NETTER-2 and COMPOSE are currently underway in patients with high grade G2 and G3 NETs. Novel SSTR antagonists are being developed as next generation targeting molecules for SSTR2-expressing tumors. Antagonists have a higher tumor binding to receptors than agonists, opening up the potential indications for SSTR2 targeting to tumors which have a relatively lower expression of SSTR2 compared to NET such as small cell lung cancer, hepatocellular carcinoma and breast cancer. In addition to Lu-177, radioisotopes with different radiation properties such as Tb-161 and the α-emitter Ac-225 are being developed which have the potential to improve treatment efficacy across the range of G1 to G3 NETs.


Assuntos
Tumores Neuroendócrinos , Humanos , Tumores Neuroendócrinos/patologia , Octreotida/uso terapêutico , Radioisótopos de Gálio , Actínio , Qualidade de Vida , Radioisótopos/uso terapêutico , Compostos Radiofarmacêuticos/uso terapêutico
10.
Front Big Data ; 5: 787421, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35496379

RESUMO

In this community review report, we discuss applications and techniques for fast machine learning (ML) in science-the concept of integrating powerful ML methods into the real-time experimental data processing loop to accelerate scientific discovery. The material for the report builds on two workshops held by the Fast ML for Science community and covers three main areas: applications for fast ML across a number of scientific domains; techniques for training and implementing performant and resource-efficient ML algorithms; and computing architectures, platforms, and technologies for deploying these algorithms. We also present overlapping challenges across the multiple scientific domains where common solutions can be found. This community report is intended to give plenty of examples and inspiration for scientific discovery through integrated and accelerated ML solutions. This is followed by a high-level overview and organization of technical advances, including an abundance of pointers to source material, which can enable these breakthroughs.

11.
Sci Data ; 9(1): 31, 2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35165298

RESUMO

To enable the reusability of massive scientific datasets by humans and machines, researchers aim to adhere to the principles of findability, accessibility, interoperability, and reusability (FAIR) for data and artificial intelligence (AI) models. This article provides a domain-agnostic, step-by-step assessment guide to evaluate whether or not a given dataset meets these principles. We demonstrate how to use this guide to evaluate the FAIRness of an open simulated dataset produced by the CMS Collaboration at the CERN Large Hadron Collider. This dataset consists of Higgs boson decays and quark and gluon background, and is available through the CERN Open Data Portal. We use additional available tools to assess the FAIRness of this dataset, and incorporate feedback from members of the FAIR community to validate our results. This article is accompanied by a Jupyter notebook to visualize and explore this dataset. This study marks the first in a planned series of articles that will guide scientists in the creation of FAIR AI models and datasets in high energy particle physics.

12.
Front Plant Sci ; 12: 762121, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34880888

RESUMO

The cell walls of forage chicory (Cichorium intybus) leaves are known to contain high proportions of pectic polysaccharides. However, little is known about the distribution of pectic polysaacharides among walls of different cell types/tissues and within walls. In this study, immunolabelling with four monoclonal antibodies was used to map the distribution of pectic polysaccharides in the cell walls of the laminae and midribs of these leaves. The antibodies JIM5 and JIM7 are specific for partially methyl-esterified homogalacturonans; LM5 and LM6 are specific for (1→4)-ß-galactan and (1→5)-α-arabinan side chains, respectively, of rhamnogalacturonan I. All four antibodies labelled the walls of the epidermal cells with different intensities. JIM5 and JIM7, but not LM5 or LM6, labelled the middle lamella, tricellular junctions, and the corners of intercellular spaces of ground, xylem and phloem parenchyma. LM5, but not LM6, strongly labelled the walls of the few sclerenchyma fibres in the phloem of the midrib and lamina vascular bundles. The LM5 epitope was absent from some phloem parenchyma cells. LM6, but not LM5, strongly labelled the walls of the stomatal guard cells. The differential distribution of pectic epitopes among walls of different cell types and within walls may reflect the deposition and modification of these polysaccharides which are involved in cell wall properties and cell development.

13.
Rep Prog Phys ; 84(12)2021 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-34736231

RESUMO

A new paradigm for data-driven, model-agnostic new physics searches at colliders is emerging, and aims to leverage recent breakthroughs in anomaly detection and machine learning. In order to develop and benchmark new anomaly detection methods within this framework, it is essential to have standard datasets. To this end, we have created the LHC Olympics 2020, a community challenge accompanied by a set of simulated collider events. Participants in these Olympics have developed their methods using an R&D dataset and then tested them on black boxes: datasets with an unknown anomaly (or not). Methods made use of modern machine learning tools and were based on unsupervised learning (autoencoders, generative adversarial networks, normalizing flows), weakly supervised learning, and semi-supervised learning. This paper will review the LHC Olympics 2020 challenge, including an overview of the competition, a description of methods deployed in the competition, lessons learned from the experience, and implications for data analyses with future datasets as well as future colliders.


Assuntos
Aprendizado de Máquina , Aprendizado de Máquina Supervisionado , Humanos , Fenômenos Físicos , Física
14.
Planta ; 254(1): 2, 2021 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-34085144

RESUMO

MAIN CONCLUSION: Heteromannans are the predominant hemicelluloses in the gametophytic stem of the moss Hypnodendron menziesii and occur in the walls of all cell types Little is known about the cell-wall polysaccharides of mosses. Monosaccharide analysis of cell walls isolated from the stem of the umbrella moss Hypnodendron menziesii was consistent with heteromannans, probably galactoglucomannans, being the predominant hemicellulosic polysaccharides in the walls. Immunofluorescence and immunogold microscopy with the monoclonal antibody LM21, specific for heteromannans, showed that these polysaccharides were present in the walls of all stem cell types. These cell types, except the hydroids, have secondary walls. Experiments in which sections were pre-treated with 0.1 M sodium carbonate and with the enzyme pectate lyase indicated that the heteromannans have O-acetyl groups that limit LM21 binding and the cell walls contain pectic homogalacturonan that masks detection of heteromannans using LM21. Therefore, to fully detect heteromannans in the cell walls, it was essential to use these pre-treatments to remove the O-acetyl groups from the heteromannans and pectic homogalacturonan from the cell walls. Fluorescence microscopy experiments with a second monoclonal antibody, LM22, also specific for heteromannans, showed similar results, but the binding was considerably weaker than with LM21, possibly as a result of subtle structural differences in the epitopes of the two antibodies. Although heteromannans occur abundantly in the cell walls of many species in basal lineages of tracheophytes, prior to the present study, research on the distribution of these polysaccharides in the walls of different cell types in mosses was confined to the model species Physcomitrium patens.


Assuntos
Briófitas , Polissacarídeos , Parede Celular , Células Germinativas Vegetais , Pectinas
15.
Hum Reprod ; 36(7): 1841-1853, 2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-34050362

RESUMO

STUDY QUESTION: What is the clinical-effectiveness and safety of the endometrial scratch (ES) procedure compared to no ES, prior to usual first time in vitro fertilisation (IVF) treatment? SUMMARY ANSWER: ES was safe but did not improve pregnancy outcomes when performed in the mid-luteal phase prior to the first IVF cycle, with or without intracytoplasmic sperm injection (ICSI). WHAT IS KNOWN ALREADY: ES is an 'add-on' treatment that is available to women undergoing a first cycle of IVF, with or without ICSI, despite a lack of evidence to support its use. STUDY DESIGN, SIZE, DURATION: This pragmatic, superiority, open-label, multi-centre, parallel-group randomised controlled trial involving 1048 women assessed the clinical effectiveness and safety of the ES procedure prior to first time IVF, with or without ICSI, between July 2016 and October 2019. PARTICIPANTS/MATERIALS, SETTING, METHODS: Participants aged 18-37 years undergoing their first cycle of IVF, with or without ICSI, were recruited from 16 UK fertility clinics and randomised (1:1) by a web-based system with restricted access rights that concealed allocation. Stratified block randomisation was used to allocate participants to TAU or ES in the mid-luteal phase followed by usual IVF with or without ICSI treatment. The primary outcome was live birth after completing 24 weeks gestation within 10.5 months of egg collection. MAIN RESULTS AND THE ROLE OF CHANCE: In total, 1048 women randomised to TAU (n = 525) and ES (n = 523) were available for intention to treat analysis. In the ES group, 453 (86.6%) received the ES procedure. IVF, with or without ICSI, was received in 494 (94.1%) and 497 (95.0%) of ES and TAU participants respectively. Live birth rate was 37.1% (195/525) in the TAU and 38.6% (202/523) in the ES: an unadjusted absolute difference of 1.5% (95% CI -4.4% to 7.4%, P = 0.621). There were no statistical differences in secondary outcomes. Adverse events were comparable across groups. LIMITATIONS, REASONS FOR CAUTION: A sham ES procedure was not undertaken in the control group, however, we do not believe this would have influenced the results as objective fertility outcomes were used. WIDER IMPLICATIONS OF THE FINDINGS: This is the largest trial that is adequately powered to assess the impact of ES on women undergoing their first cycle of IVF. ES was safe, but did not significantly improve pregnancy outcomes when performed in the mid-luteal phase prior to the first IVF or ICSI cycle. We recommend that ES is not undertaken in this population. STUDY FUNDING/COMPETING INTEREST(S): Funded by the National Institute of Health Research. Stephen Walters is an National Institute for Health Research (NIHR) Senior Investigator (2018 to present) and was a member of the following during the project: National Institute for Health Research (NIHR) Health Technology Assessment (HTA) Clinical Trials and Evaluation Committee (2011-2017), NIHR HTA Commissioning Strategy Group (2012 to 2017); NIHR Programme Grants for Applied Research Committee (2020 to present); NIHR Pre doctoral Fellowship Committee (2019 to present). Dr. Martins da Silva reports grants from AstraZeneca, during the conduct of the study; and is Associate editor of Human Reproduction and Editorial Board member of Reproduction and Fertility. Dr. Bhide reports grants from Bart's Charity and grants and non-financial support from Pharmasure Pharmaceuticals outside the submitted work. TRIAL REGISTRATION NUMBER: ISRCTN number: ISRCTN23800982. TRIAL REGISTRATION DATE: 31 May 2016. DATE OF FIRST PATIENT'S ENROLMENT: 04 July 2016.


Assuntos
Fertilização in vitro , Injeções de Esperma Intracitoplásmicas , Coeficiente de Natalidade , Feminino , Humanos , Fase Luteal , Gravidez , Taxa de Gravidez , Resultado do Tratamento
16.
Expert Opin Ther Pat ; 31(2): 137-151, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33249869

RESUMO

Introduction: RIP1 kinase is a serine/threonine-protein kinase that has recently emerged as a central regulator of TNF-α dependent programmed necrosis (necroptosis), an inflammatory form of cell death, with important roles in inflammation and neurodegeneration. Small molecule RIP1 kinase inhibitors may provide new opportunities for treating a variety of autoimmune, inflammatory, and neurodegenerative diseases, among others, and thus have attracted widespread drug development efforts and a corresponding large amount of patent activity in recent years. Areas covered: This review focuses on the patent literature covering small molecule inhibitors of RIP1 kinase from 2016-present. Expert opinion: Inhibition of programmed necrosis (necroptosis) by RIP1 kinase inhibitors is a new field that has attracted widespread recent interest as a possible therapeutic means to treat a number of diseases in the inflammatory, neurodegenerative, and oncology areas. The interest in the therapeutic potential of RIP1kinase is evidenced by more than 40 small molecule patent applications published since 2016. To date, only a few RIP1 kinase inhibitors have entered the clinic. An understanding of the optimal clinical setting, in terms of dosing and disease indications for RIP1 inhibition, will require further clinical readouts as the current inhibitors progress and additional molecules enter into full development.


Assuntos
Desenvolvimento de Medicamentos , Inibidores de Proteínas Quinases/farmacologia , Proteína Serina-Treonina Quinases de Interação com Receptores/antagonistas & inibidores , Animais , Humanos , Inflamação/tratamento farmacológico , Inflamação/enzimologia , Necroptose/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Neoplasias/enzimologia , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/enzimologia , Patentes como Assunto , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo
18.
Methods Mol Biol ; 2149: 203-223, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32617937

RESUMO

A knowledge of the mobilities of the polysaccharides or parts of polysaccharides in a cell-wall preparation provides information about possible molecular interactions among the polysaccharides in the cell wall and the relative locations of polysaccharides within the cell wall. A number of solid-state 13C NMR techniques have been developed that can be used to investigate different types of polysaccharide mobilities: rigid, semirigid, mobile, and highly mobile. In this chapter techniques are described for obtaining spectra from primary cell-wall preparations using CP/MAS, proton-rotating frame, proton spin-spin, spin-echo relaxation spectra and single-pulse excitation. We also describe how proton spin relaxation editing can be used to obtain subspectra for cell-wall polysaccharides of different mobilities, and how 2D and 3D solid-state NMR experiments have recently been applied to plant cell walls.


Assuntos
Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Parede Celular/química , Células Vegetais/química , Difusão , Polissacarídeos/química , Prótons , Marcadores de Spin
19.
Sci Rep ; 10(1): 7719, 2020 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-32382043

RESUMO

This multicentre, randomised, controlled cross-over trial was designed to investigate the effect of intra-uterine slow-release insemination (SRI) on pregnancy rates in women with confirmed infertility or the need for semen donation who were eligible for standard bolus intra-uterine insemination (IUI). Data for a total of 182 women were analysed after randomisation to receive IUI (n = 96) or SRI (n = 86) first. The primary outcome was serological pregnancy defined by a positive beta human chorionic gonadotropin test, two weeks after insemination. Patients who did not conceive after the first cycle switched to the alternative technique for the second cycle: 44 women switched to IUI and 58 switched to SRI. In total, there were 284 treatment cycles (IUI: n = 140; SRI: n = 144). Pregnancy rates following SRI and IUI were 13.2% and 10.0%, respectively, which was not statistically significant (p = 0.202). A statistically significant difference in pregnancy rates for SRI versus IUI was detected in women aged under 35 years. In this subgroup, the pregnancy rate with SRI was 17% compared to 7% with IUI (relative risk 2.33; p = 0.032) across both cycles. These results support the hypothesis that the pregnancy rate might be improved with SRI compared to standard bolus IUI, especially in women aged under 35 years.


Assuntos
Fertilização in vitro/métodos , Infertilidade/terapia , Inseminação Artificial/métodos , Taxa de Gravidez , Adolescente , Adulto , Gonadotropina Coriônica/metabolismo , Feminino , Humanos , Infertilidade/patologia , Nascido Vivo/epidemiologia , Masculino , Gravidez , Doadores de Tecidos , Adulto Jovem
20.
Front Big Data ; 3: 598927, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33791596

RESUMO

Graph neural networks have been shown to achieve excellent performance for several crucial tasks in particle physics, such as charged particle tracking, jet tagging, and clustering. An important domain for the application of these networks is the FGPA-based first layer of real-time data filtering at the CERN Large Hadron Collider, which has strict latency and resource constraints. We discuss how to design distance-weighted graph networks that can be executed with a latency of less than one µs on an FPGA. To do so, we consider a representative task associated to particle reconstruction and identification in a next-generation calorimeter operating at a particle collider. We use a graph network architecture developed for such purposes, and apply additional simplifications to match the computing constraints of Level-1 trigger systems, including weight quantization. Using the hls4ml library, we convert the compressed models into firmware to be implemented on an FPGA. Performance of the synthesized models is presented both in terms of inference accuracy and resource usage.

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