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1.
Biochem J ; 481(11): 669-682, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38713013

RESUMO

The fundamental biology of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleocapsid protein (Ncap), its use in diagnostic assays and its potential application as a vaccine component have received considerable attention since the outbreak of the Covid19 pandemic in late 2019. Here we report the scalable expression and purification of soluble, immunologically active, SARS-CoV-2 Ncap in Escherichia coli. Codon-optimised synthetic genes encoding the original Ncap sequence and four common variants with an N-terminal 6His affinity tag (sequence MHHHHHHG) were cloned into an inducible expression vector carrying a regulated bacteriophage T5 synthetic promoter controlled by lac operator binding sites. The constructs were used to express Ncap proteins and protocols developed which allow efficient production of purified Ncap with yields of over 200 mg per litre of culture media. These proteins were deployed in ELISA assays to allow comparison of their responses to human sera. Our results suggest that there was no detectable difference between the 6His-tagged and untagged original Ncap proteins but there may be a slight loss of sensitivity of sera to other Ncap isolates.


Assuntos
COVID-19 , Proteínas do Nucleocapsídeo de Coronavírus , Escherichia coli , SARS-CoV-2 , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas do Nucleocapsídeo de Coronavírus/genética , Proteínas do Nucleocapsídeo de Coronavírus/metabolismo , Proteínas do Nucleocapsídeo de Coronavírus/biossíntese , Proteínas do Nucleocapsídeo de Coronavírus/isolamento & purificação , Proteínas do Nucleocapsídeo de Coronavírus/química , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Humanos , COVID-19/virologia , Fosfoproteínas/genética , Fosfoproteínas/isolamento & purificação , Fosfoproteínas/metabolismo
2.
Microbiology (Reading) ; 168(12)2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36748525

RESUMO

Peptide transporters play important nutritional and cell signalling roles in Bacillus subtilis, which are pronounced during stationary phase adaptations and development. Three high-affinity ATP-binding cassette (ABC) family transporters are involved in peptide uptake - the oligopeptide permease (Opp), another peptide permease (App) and a less well-characterized dipeptide permease (Dpp). Here we report crystal structures of the extracellular substrate binding proteins, OppA and DppE, which serve the Opp and Dpp systems, respectively. The structure of OppA was determined in complex with endogenous peptides, modelled as Ser-Asn-Ser-Ser, and with the sporulation-promoting peptide Ser-Arg-Asn-Val-Thr, which bind with K d values of 0.4 and 2 µM, respectively, as measured by isothermal titration calorimetry. Differential scanning fluorescence experiments with a wider panel of ligands showed that OppA has highest affinity for tetra- and penta-peptides. The structure of DppE revealed the unexpected presence of a murein tripeptide (MTP) ligand, l-Ala-d-Glu-meso-DAP, in the peptide binding groove. The mode of MTP binding in DppE is different to that observed in the murein peptide binding protein, MppA, from Escherichia coli, suggesting independent evolution of these proteins from an OppA-like precursor. The presence of MTP in DppE points to a role for Dpp in the uptake and recycling of cell wall peptides, a conclusion that is supported by analysis of the genomic context of dpp, which revealed adjacent genes encoding enzymes involved in muropeptide catabolism in a gene organization that is widely conserved in Firmicutes.


Assuntos
Bacillus subtilis , Peptidoglicano , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Peptidoglicano/metabolismo , Proteínas de Bactérias/metabolismo , Oligopeptídeos , Proteínas de Membrana Transportadoras/metabolismo , Escherichia coli/genética , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo
3.
Biochem J ; 477(22): 4383-4395, 2020 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-33111951

RESUMO

A fragment screen of a library of 560 commercially available fragments using a kinetic assay identified a small molecule that increased the activity of the fungal glycoside hydrolase TrBgl2. An analogue by catalogue approach and detailed kinetic analysis identified improved compounds that behaved as nonessential activators with up to a 2-fold increase in maximum activation. The compounds did not activate the related bacterial glycoside hydrolase CcBglA demonstrating specificity. Interestingly, an analogue of the initial fragment inhibits both TrBgl2 and CcBglA, apparently through a mixed-model mechanism. Although it was not possible to determine crystal structures of activator binding to 55 kDa TrBgl2, solution NMR experiments demonstrated a specific binding site for the activator. A partial assignment of the NMR spectrum gave the identity of the amino acids at this site, allowing a model for TrBgl2 activation to be built. The activator binds at the entrance of the substrate-binding site, generating a productive conformation for the enzyme-substrate complex.


Assuntos
Ativadores de Enzimas/química , Proteínas Fúngicas/química , Hypocreales/química , beta-Glucosidase/química , Ressonância Magnética Nuclear Biomolecular
4.
Am Fam Physician ; 104(3): 244-252, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34523885

RESUMO

Kawasaki disease (KD) and multisystem inflammatory syndrome in children (MIS-C) are inflammatory conditions that present diagnostic and therapeutic challenges to the physician. Although many of their features overlap, they are two distinct conditions. KD is a febrile illness most commonly affecting children younger than five years. It manifests with prolonged fever and at least four of the following features: bilateral bulbar conjunctivitis, mucositis, diffuse maculopapular rash, extremity changes, and cervical lymphadenopathy of 1.5 cm or more in diameter. Patients with MIS-C may have many of the same manifestations but tend to have higher rates of gastrointestinal and neurocognitive symptoms and signs of shock on presentation. Both conditions are associated with cardiac sequelae, including coronary artery aneurysms, although children with MIS-C are at high risk of developing ventricular dysfunction and depressed cardiac output. Lymphocytopenia, thrombocytopenia, elevated troponin, and elevated B-type natriuretic peptide are key laboratory findings of MIS-C that can help distinguish it from KD. The use of intravenous immune globulin is well established in KD and also appears to have a role in the treatment of MIS-C. Aspirin has been used in KD for an anti-inflammatory effect, and low-dose aspirin is recommended for MIS-C to reduce the risk of thrombosis. In addition to supportive care, patients with MIS-C may benefit from immunomodulatory medications, although data on this topic are evolving.


Assuntos
COVID-19/fisiopatologia , Síndrome de Linfonodos Mucocutâneos/fisiopatologia , Síndrome de Resposta Inflamatória Sistêmica/fisiopatologia , COVID-19/complicações , COVID-19/epidemiologia , Correlação de Dados , Humanos , Síndrome de Linfonodos Mucocutâneos/complicações , Síndrome de Linfonodos Mucocutâneos/epidemiologia , Síndrome de Resposta Inflamatória Sistêmica/complicações , Síndrome de Resposta Inflamatória Sistêmica/epidemiologia
5.
Sensors (Basel) ; 20(4)2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32079359

RESUMO

Nicotine consumption is considered a major health problem, where many of those who wish to quit smoking relapse. The problem is that overtime smoking as behaviour is changing into a habit, in which it is connected to internal (e.g., nicotine level, craving) and external (action, time, location) triggers. Smoking cessation apps have proved their efficiency to support smoking who wish to quit smoking. However, still, these applications suffer from several drawbacks, where they are highly relying on the user to initiate the intervention by submitting the factor the causes the urge to smoke. This research describes the creation of a combined Control Theory and deep learning model that can learn the smoker's daily routine and predict smoking events. The model's structure combines a Control Theory model of smoking with a 1D-CNN classifier to adapt to individual differences between smokers and predict smoking events based on motion and geolocation values collected using a mobile device. Data were collected from 5 participants in the UK, and analysed and tested on 3 different machine learning model (SVM, Decision tree, and 1D-CNN), 1D-CNN has proved it's efficiency over the three methods with average overall accuracy 86.6%. The average MSE of forecasting the nicotine level was (0.04) in the weekdays, and (0.03) in the weekends. The model has proved its ability to predict the smoking event accurately when the participant is well engaged with the app.


Assuntos
Aprendizado de Máquina , Aplicativos Móveis , Abandono do Hábito de Fumar/métodos , Fumar/terapia , Humanos , Masculino , Fumantes/psicologia , Fumar/epidemiologia
6.
J Am Chem Soc ; 141(40): 15818-15826, 2019 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-31518131

RESUMO

Solvent organization is a key but underexploited contributor to the thermodynamics of protein-ligand recognition, with implications for ligand discovery, drug resistance, and protein engineering. Here, we explore the contribution of solvent to ligand binding in the Haemophilus influenzae virulence protein SiaP. By introducing a single mutation without direct ligand contacts, we observed a >1000-fold change in sialic acid binding affinity. Crystallographic and calorimetric data of wild-type and mutant SiaP showed that this change results from an enthalpically unfavorable perturbation of the solvent network. This disruption is reflected by changes in the normalized atomic displacement parameters of crystallographic water molecules. In SiaP's enclosed cavity, relative differences in water-network dynamics serve as a simple predictor of changes in the free energy of binding upon changing protein, ligand, or both. This suggests that solvent structure is an evolutionary constraint on protein sequence that contributes to ligand affinity and selectivity.


Assuntos
Solventes/química , Proteínas Virais/química , Fatores de Virulência/química , Água/química , Sítios de Ligação , Ligantes , Ligação Proteica , Conformação Proteica , Termodinâmica
7.
J Ment Health ; 28(1): 34-41, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30445899

RESUMO

BACKGROUND: Early identification of probable post-traumatic stress disorder (PTSD) can lead to early intervention and treatment. AIMS: This study aimed to evaluate supervised machine learning (ML) classifiers for the identification of probable PTSD in those who are serving, or have recently served in the United Kingdom (UK) Armed Forces. METHODS: Supervised ML classification techniques were applied to a military cohort of 13,690 serving and ex-serving UK Armed Forces personnel to identify probable PTSD based on self-reported service exposures and a range of validated self-report measures. Data were collected between 2004 and 2009. RESULTS: The predictive performance of supervised ML classifiers to detect cases of probable PTSD were encouraging when compared to a validated measure, demonstrating a capability of supervised ML to detect the cases of probable PTSD. It was possible to identify which variables contributed to the performance, including alcohol misuse, gender and deployment status. A satisfactory sensitivity was obtained across a range of supervised ML classifiers, but sensitivity was low, indicating a potential for false negative diagnoses. CONCLUSIONS: Detection of probable PTSD based on self-reported measurement data is feasible, may greatly reduce the burden on public health and improve operational efficiencies by enabling early intervention, before manifestation of symptoms.


Assuntos
Militares/psicologia , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Aprendizado de Máquina Supervisionado , Adulto , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Reino Unido , Adulto Jovem
9.
Angew Chem Int Ed Engl ; 53(49): 13419-23, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25291993

RESUMO

Fragment-based approaches are used routinely to discover enzyme inhibitors as cellular tools and potential therapeutic agents. There have been few reports, however, of the discovery of small-molecule enzyme activators. Herein, we describe the discovery and characterization of small-molecule activators of a glycoside hydrolase (a bacterial O-GlcNAc hydrolase). A ligand-observed NMR screen of a library of commercially available fragments identified an enzyme activator which yielded an approximate 90 % increase in kcat /KM  values (kcat =catalytic rate constant; KM =Michaelis constant). This compound binds to the enzyme in close proximity to the catalytic center. Evolution of the initial hits led to improved compounds that behave as nonessential activators effecting both KM  and Vmax  values (Vmax =maximum rate of reaction). The compounds appear to stabilize an active "closed" form of the enzyme. Such activators could offer an orthogonal alternative to enzyme inhibitors for perturbation of enzyme activity in vivo, and could also be used for glycoside hydrolase activation in many industrial processes.


Assuntos
Bacteroides/enzimologia , Ativação Enzimática/efeitos dos fármacos , Glicosídeo Hidrolases/metabolismo , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Bacteroides/química , Cristalografia por Raios X , Glicosídeo Hidrolases/química , Modelos Moleculares
10.
Hosp Pediatr ; 13(4): 308-318, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36974612

RESUMO

OBJECTIVES: To identify demographic and clinical characteristics of children with fever and/or respiratory illness associated with a diagnosis of bacterial tracheostomy-associated respiratory tract infections (bTARTI). Secondary objectives included comparison of diagnostic testing, length of stay (LOS), and readmission rates between children diagnosed with bTARTI and others. METHODS: We performed a retrospective chart review of encounters over 1 year for fever and/or respiratory illness at a single academic children's hospital for children with tracheostomy dependence. Patient characteristics, features of presenting illness, and laboratory and imaging results were collected. Generalized linear mixed models were employed to study associations between patient characteristics, diagnosis of bTARTI, and impact on LOS or readmission rates. RESULTS: Among 145 children with tracheostomies identified, 79 children contributed 208 encounters. bTARTI was diagnosed in 66 (31.7%) encounters. Significant associations with bTARTI diagnosis included chest radiograph consistent with bacterial pneumonia (odds ratio [OR], 1.77; 95% confidence interval [CI], 1.50-2.08), positive tracheal aspirate culture (OR, 1.3; 95% CI, 1.05-1.61), higher white blood cell count (16.4 vs 13.1 × 103/µ; P = .03), change in oxygen requirement (OR, 1.14; 95% CI, 1.00-1.31), telephone encounter (OR, 1.41; 95% CI, 1.09-1.81), and living at home with family (OR, 1.42; 95% CI, 1.06-1.92). LOS for admitted patients with bTARTI was 2.19 times longer (CI, 1.23-3.88). CONCLUSIONS: In our single-center study, we identified several clinical and nonclinical factors associated with a diagnosis of bTARTI. Despite widespread use, few laboratory tests were predictive of a diagnosis of bTARTI. There is need for standardization in diagnosis.


Assuntos
Infecções Bacterianas , Infecções Respiratórias , Criança , Humanos , Lactente , Traqueostomia/efeitos adversos , Estudos Retrospectivos , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/epidemiologia , Hospitalização , Tempo de Internação
11.
BMJ Open ; 13(3): e068204, 2023 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-36931669

RESUMO

The COVID-19 pandemic has significantly impacted on the delivery of clinical trials in the UK, posing complicated organisational challenges and requiring adaptations, especially to exercise intervention studies based in the community. We aim to identify the challenges of public involvement, recruitment, consent, follow-up, intervention and the healthcare professional delivery aspects of a feasibility study of exercise in hypertensive primary care patients during the COVID-19 pandemic. While these challenges elicited many reactive changes which were specific to, and only relevant in the context of 'lockdown' requirements, some of the protocol developments that came about during this unprecedented period have great potential to inform more permanent practices for carrying out this type of research. To this end, we detail the necessary adaptations to many elements of the feasibility study and critically reflect on our approach to redesigning and amending this ongoing project in order to maintain its viability to date. Some of the more major protocol adaptations, such as moving the study to remote means wherever possible, had further unforeseen and undesirable outcomes (eg, additional appointments) with regards to extra resources required to deliver the study. However, other changes improved the efficiency of the study, such as the remote informed consent and the direct advertising with prescreening survey. The adaptations to the study have clear links to the UK Plan for the future of research delivery. It is intended that this specific documentation and critical evaluation will help those planning or delivering similar studies to do so in a more resource efficient and effective way. In conclusion, it is essential to reflect and respond with protocol changes in the current climate in order to deliver clinical research successfully, as in the case of this particular study.


Assuntos
COVID-19 , Hipertensão , Humanos , COVID-19/epidemiologia , SARS-CoV-2 , Pandemias/prevenção & controle , Estudos de Viabilidade , Exercício Físico , Hipertensão/terapia
13.
Acad Pediatr ; 22(3): 440-446, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34252607

RESUMO

OBJECTIVE: The impact of trainees on inpatient patient care is incompletely understood. This study sought to discern the impact of trainees on patient outcomes and costs at a children's hospital in the community. We hypothesized that there would be no differences in patient outcomes and costs on an inpatient teaching service compared to a nonteaching service. As a secondary goal, we analyzed trainee evaluations. METHODS: The authors conducted a cohort study of patients hospitalized from October 1, 2016 to September 30, 2017 on an acute care unit in a children's hospital in the community. Using t test or Fisher exact test, the authors compared patient outcomes between teaching and nonteaching services including, length of stay, discharge times, readmission rates, rapid response team (RRT) calls, pediatric intensive care unit (PICU) transfers, hospital transfers, and costs. RESULTS: During the study period, there were 1066 patients admitted and discharged from the teaching service and 1038 from the nonteaching service. There were no statistically significant differences in patient demographics or patient complexity. Similarly, there were no differences in length of stay, discharge times, readmission rates, RRT calls, PICU transfers, hospital transfers or patient costs between services. Trainee evaluations of the inpatient experience were overwhelmingly positive. CONCLUSIONS: In a children's hospital in the community, there were no significant differences in patient outcomes and costs on a teaching service compared to a nonteaching service. Furthermore, trainee evaluations suggested a favorable learning experience, illustrating the feasibility of incorporating trainees into inpatient care in a nontraditional learner setting.


Assuntos
Hospitais Pediátricos , Hospitais de Ensino , Criança , Estudos de Coortes , Hospitalização , Humanos , Tempo de Internação , Estudos Retrospectivos
14.
Hosp Pediatr ; 2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35194637

RESUMO

OBJECTIVES: Describe the prevalence of different care models for children with Kawasaki disease (KD) and evaluate utilization and cardiac outcomes by care model. METHODS: Multicenter, retrospective cohort study of children aged 0 to 18 hospitalized with KD in US children's hospitals from 2017 to 2018. We classified hospital model of care via survey: hospitalist primary service with as-needed consultation (Model 1), hospitalist primary service with automatic consultation (Model 2), or subspecialist primary service (Model 3). Additional data sources included administrative data from the Pediatric Health Information System database supplemented by a 6-site chart review. Utilization outcomes included laboratory, medication and imaging usage, length of stay, and readmission rates. We measured the frequency of coronary artery aneurysms (CAAs) in the full cohort and new CAAs within 12 weeks in the 6-site chart review subset. RESULTS: We included 2080 children from 44 children's hospitals; 21 hospitals (48%) identified as Model 1, 19 (43%) as Model 2, and 4 (9%) as Model 3. Model 1 institutions obtained more laboratory tests and had lower overall costs (P < .001), whereas echocardiogram (P < .001) and immune modulator use (P < .001) were more frequent in Model 3. Secondary outcomes, including length of stay, readmission rates, emergency department revisits, CAA frequency, receipt of anticoagulation, and postdischarge CAA development, did not differ among models. CONCLUSIONS: Modest cost and utilization differences exist among different models of care for KD without significant differences in outcomes. Further research is needed to investigate primary service and consultation practices for KD to optimize health care value and outcomes.

15.
Hosp Pediatr ; 11(1): 1-7, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33262220

RESUMO

OBJECTIVES: Secondhand smoke exposure is associated with adverse health outcomes in children, yet tobacco cessation efforts for caregivers of hospitalized children are lacking. We sought to explore pediatric hospitalists' attitudes and barriers to providing tobacco cessation for caregivers of hospitalized children. METHODS: We conducted a cross-sectional survey of pediatric hospitalists and fellows at 7 hospitals from November 1, 2018, to November 30, 2019. A 70-question anonymous survey was used to assess participants' perceptions of current practices, attitudes, and barriers to providing tobacco cessation support for caregivers of hospitalized children. We used descriptive statistics to summarize the data. RESULTS: Of 207 eligible participants, 100 responded (48%). A majority (79%) agreed that offering tobacco cessation counseling for caregivers is an important part of their role in caring for hospitalized children, but 79% never received tobacco cessation training. Only half of the participants were comfortable providing brief advice and few were comfortable prescribing nicotine replacement therapy. Identified barriers included lack of time (74%), perceived lack of interest from patients' caregivers (71%), and other medical conditions of the patient taking priority (70%). The majority of participants were interested in further training in tobacco cessation support. CONCLUSIONS: In this survey of 100 pediatric hospitalists, we found overall agreement that tobacco cessation support for caregivers of hospitalized children is important. However, most participants did not feel comfortable with provision of evidence-based counseling or pharmacotherapy because of identified barriers. Future work should target actionable barriers to improve provision of tobacco cessation support in this clinical setting.


Assuntos
Médicos Hospitalares , Abandono do Hábito de Fumar , Abandono do Uso de Tabaco , Cuidadores , Criança , Criança Hospitalizada , Aconselhamento , Estudos Transversais , Humanos , Dispositivos para o Abandono do Uso de Tabaco
16.
Pilot Feasibility Stud ; 7(1): 192, 2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34711266

RESUMO

BACKGROUND: Hypertension  (HTN) affects approximately 25% of the UK population and is a leading cause of mortality. Associated annual health care costs run into billions. National treatment guidance includes initial lifestyle advice, followed by anti-hypertensive medication if blood pressure (BP) remains high. However, adoption and adherence to recommended exercise guidelines, dietary advice and anti-hypertensive medication is poor. Four short bouts of isometric exercise (IE) performed 3 days per week (d/wk) at home elicits clinically significant reductions in BP in those with normal to high-normal BP. This study will determine the feasibility of delivering personalised IE to patients with stage 1 hypertension for whom lifestyle changes would be recommended before medication within NHS primary care. METHODS: This is a randomised controlled feasibility study. Participants were 18+ years, with stage 1 hypertension, not on anti-hypertensive medication and without significant medical contraindications. Trial arms will be standard lifestyle advice (control) or isometric wall squat exercise and standard lifestyle advice. Primary outcomes include the feasibility of healthcare professionals to deliver isometric exercise prescriptions in a primary care NHS setting and estimation of the variance of change in systolic BP. Secondary outcomes include accuracy of protocol delivery, execution of and adherence to protocol, recruitment rate, attrition, perception of intervention viability, cost, participant experience and accuracy of home BP. The study will last 18 months. Sample size of 100 participants (50 per arm) allows for 20% attrition and 6.5% incomplete data, based upon 74 (37 each arm) participants (two-sided 95% confidence interval, width of 1.33 and standard deviation of 4) completing 4 weeks. Ethical approval IRAS ID is 274676. DISCUSSION: Before the efficacy of this novel intervention to treat stage 1 hypertension can be investigated in any large randomised controlled trial, it is necessary to ascertain if it can be delivered and carried out in a NHS primary care setting. Findings could support IE viability as a prophylactic/alternative treatment option. TRIAL REGISTRATION: ISRCTN13472393 , registered 18 August 2020.

17.
Sci Rep ; 10(1): 16000, 2020 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-32994435

RESUMO

Heat shock protein 90 (Hsp90) is a molecular chaperone that plays an important role in tumour biology by promoting the stabilisation and activity of oncogenic 'client' proteins. Inhibition of Hsp90 by small-molecule drugs, acting via its ATP hydrolysis site, has shown promise as a molecularly targeted cancer therapy. Owing to the importance of Hop and other tetratricopeptide repeat (TPR)-containing cochaperones in regulating Hsp90 activity, the Hsp90-TPR domain interface is an alternative site for inhibitors, which could result in effects distinct from ATP site binders. The TPR binding site of Hsp90 cochaperones includes a shallow, positively charged groove that poses a significant challenge for druggability. Herein, we report the apo, solution-state structure of Hop TPR2A which enables this target for NMR-based screening approaches. We have designed prototype TPR ligands that mimic key native 'carboxylate clamp' interactions between Hsp90 and its TPR cochaperones and show that they block binding between Hop TPR2A and the Hsp90 C-terminal MEEVD peptide. We confirm direct TPR-binding of these ligands by mapping 1H-15N HSQC chemical shift perturbations to our new NMR structure. Our work provides a novel structure, a thorough assessment of druggability and robust screening approaches that may offer a potential route, albeit difficult, to address the chemically challenging nature of the Hop TPR2A target, with relevance to other TPR domain interactors.


Assuntos
Proteínas de Choque Térmico/química , Proteínas de Choque Térmico/metabolismo , Bibliotecas de Moléculas Pequenas/farmacologia , Domínio Catalítico , Simulação por Computador , Humanos , Ligantes , Modelos Moleculares , Ressonância Magnética Nuclear Biomolecular , Ligação Proteica , Conformação Proteica , Domínios Proteicos , Bibliotecas de Moléculas Pequenas/química
18.
Hosp Pediatr ; 9(9): 724-728, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31462419

RESUMO

OBJECTIVE: To explore practice variations in the care of patients with Kawasaki disease (KD) among pediatric hospitalist physicians (PHPs). METHODS: A 13-item questionnaire was developed by a multi-institutional group of KD experts. The survey was administered via live-audience polling by using smartphone technology during a KD plenary session at the 2017 Pediatric Hospital Medicine National Meeting, and simple descriptive statistics were calculated. RESULTS: Of the 297 session attendees, 90% responded to at least 1 survey question. Approximately three-quarters of respondents identified as PHPs practicing in the United States. The reported length of inpatient monitoring after initial intravenous immunoglobulin (IVIG) therapy demonstrated a wide time distribution (30% 24 hours, 36% 36 hours, and 31% 48 hours). Similarly, PHP identification of the treatment failure interval, indicated by recrudescent fever after IVIG, demonstrated a broad distribution (56% 24 hours, 27% 36 hours, and 16% 48 hours). Furthermore, there was variation in routine consultation with non-PHP subspecialists. In contrast, PHPs reported little variation in their choice of initial and refractory treatment of patients with KD. CONCLUSIONS: In a convenience sample at a national hospitalist meeting, there was variation in reported KD practice patterns, including observation time after initial treatment, time when the recurrence of fever after initial therapy was indicative of nonresponse to IVIG, and routine consultation of non-PHP subspecialists. These results may guide future study of KD practice patterns and inform efforts to improve evidence-based practices in the care of patients with KD.


Assuntos
Médicos Hospitalares/estatística & dados numéricos , Hospitais Pediátricos/estatística & dados numéricos , Síndrome de Linfonodos Mucocutâneos/terapia , Padrões de Prática Médica/estatística & dados numéricos , Criança , Estudos Transversais , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Inquéritos e Questionários
19.
Clin Drug Investig ; 28(9): 553-64, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18666802

RESUMO

BACKGROUND AND OBJECTIVE: Conflicting therapeutic drug monitoring (TDM) results have been reported for risperidone and olanzapine. This study set out to examine the long-term pharmacokinetics of risperidone and olanzapine in a locked skilled nursing facility where medication administration was controlled by nursing staff. METHODS: TDM was performed in a long-term treatment protocol for risperidone and olanzapine in 67 refractory chronic schizophrenic patients in a locked, skilled nursing facility. TDM was performed 632 times in the risperidone group of 34 patients and 563 times in the olanzapine group of 33 patients. The logarithm of plasma concentrations were analysed through time by piecewise linear mixed model regressions adjusted for the logarithm of dose. RESULTS: We found risperidone plasma concentration/dose ratio (C/D) accumulation peaks of 49% at 2 months (from baseline concentration) and 9-hydroxy-risperidone and total moiety C/D accumulation peaks of 66% and 55% above the 2-month level at 6 months, which are somewhat similar to those found in our prior study that included a subset of data points analysed here. The risperidone conversion to 9-hydroxy-risperidone by cytochrome P450 (CYP) 2D6 suggests CYP2D6 inhibition or DNA down-regulation in the first 2 months. Olanzapine showed a C/D accumulation peak at 4 months of 31% above baseline, and a slower increase to 47% above baseline at 18 months with no clear plateau. CONCLUSION: We identified five potential perturbations in the pharmacokinetics of risperidone and olanzapine that could potentially lead to adverse drug reactions. These long-term effects would not be captured by a standard 5-day pharmacokinetic TDM developmental testing model for antipsychotics, and a new model for characterizing variation in C/D by time course is therefore proposed. The time course of the accumulations identified suggests that both CYP inhibition and DNA regulatory mechanisms may be involved in the metabolism of these drugs. Long-term TDM can optimize treatment with risperidone and olanzapine and antipsychotics in general.


Assuntos
Antipsicóticos/farmacocinética , Benzodiazepinas/farmacocinética , Risperidona/farmacocinética , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Antipsicóticos/análise , Antipsicóticos/uso terapêutico , Benzodiazepinas/análise , Benzodiazepinas/uso terapêutico , Biotransformação , Citocromo P-450 CYP2D6/metabolismo , Monitoramento de Medicamentos , Feminino , Humanos , Pacientes Internados , Isoxazóis/sangue , Masculino , Transtornos Mentais/tratamento farmacológico , Transtornos Mentais/metabolismo , Pessoa de Meia-Idade , Olanzapina , Palmitato de Paliperidona , Pirimidinas/sangue , Análise de Regressão , Risperidona/análise , Risperidona/uso terapêutico , Esquizofrenia/sangue , Esquizofrenia/tratamento farmacológico , Adulto Jovem
20.
Gait Posture ; 65: 45-50, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30558945

RESUMO

BACKGROUND: Physical therapy evaluations of motor control are currently based on subjective clinical assessments. Despite validation, these can still be inconsistent between therapists and between clinics, compromising the process of validating a therapeutic intervention and the subsequent generation of evidence-based practice (EBP) guidelines. EBP benefits from well-defined objective measurements that complement existing subjective assessments. RESEARCH QUESTION: The aim of this study was to develop an objective measure of head/trunk control in children with Cerebral Palsy (CP) using previously developed video-based methods of head/trunk alignment and absence of external support and compare these with the existing subjective Segmental Assessment of Trunk Control (SATCo). METHODS: Twelve children with CP were recruited and an average of 3 (±1.1) SATCo tests performed per child. The full SATCo was concurrently video-recorded from a sagittal view; markers were placed on specific landmarks of the head, trunk and pelvis to track and estimate head/trunk segment position. A simplified objective rule was created for control and used on videos showing no external support. This replicated the clinical parameters and enabled identification of the segmental-loss-of-control. The subjectively and objectively identified segmental-loss-of-control were compared using a Pearson Correlation Coefficient. RESULTS: An angular-threshold of 17° from alignment showed the minimum bias between the subjectively and the objectively measured segmental-loss-of-control (mean error =-0.11 and RMSE = 1.5) and a significant correlation (r = 0.78, r2 = 0.61, p < .01). SIGNIFICANCE: This study showed that simple objective video-based measurements can be used to reconstruct the subjective assessment of segmental head/trunk control. This suggests that a clinically-friendly video-based objective measure has future potential to complement subjective assessments and to assist in the generation of EBP guidelines. Further development will increase the information that can be extracted from video images and enable generation of a fully automated objective measure.


Assuntos
Paralisia Cerebral/fisiopatologia , Cabeça/fisiopatologia , Postura/fisiologia , Tronco/fisiopatologia , Criança , Pré-Escolar , Feminino , Humanos , Pelve/fisiopatologia , Gravação em Vídeo/métodos
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