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1.
J Chromatogr A ; 1730: 465110, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38941794

RESUMO

Maximizing product quality attributes by optimizing process parameters and performance attributes is a crucial aspect of bioprocess chromatography process design. Process parameters include but are not limited to bed height, eluate cut points, and elution pH. An under-characterized chromatography process parameter for protein A chromatography is process temperature. Here, we present a mechanistic understanding of the effects of temperature on the protein A purification of a monoclonal antibody (mAb) using a commercial chromatography resin for batch and continuous counter-current systems. A self-designed 3D-printed heating jacket controlled the 1 mL chromatography process temperature during the loading, wash, elution, and cleaning-in-place (CIP) steps. Batch loading experiments at 10, 20, and 30 °C demonstrated increased dynamic binding capacity (DBC) with temperature. The experimental data were fit to mechanistic and correlation-based models that predicted the optimal operating conditions over a range of temperatures. These model-based predictions optimized the development of a 3-column temperature-controlled periodic counter-current chromatography (TCPCC) and were validated experimentally. Operating a 3-column TCPCC at 30 °C led to a 47% increase in DBC relative to 20 °C batch chromatography. The DBC increase resulted in a two-fold increase in productivity relative to 20 °C batch. Increasing the number of columns to the TCPCC to optimize for increasing feed concentration resulted in further improvements to productivity. The feed-optimized TCPCC showed a respective two, three, and four-fold increase in productivity at feed concentrations of 1, 5, and 15 mg/mL mAb, respectively. The derived and experimentally validated temperature-dependent models offer a valuable tool for optimizing both batch and continuous chromatography systems under various operating conditions.

2.
J Hand Surg Eur Vol ; : 17531934241253479, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38780136

RESUMO

We report the case of a 15-year-old boy with a de novo chromosomal deletion in the 12q13.13 region, presenting with congenital hand difference. This case emphasizes the clinical significance of recognizing such genetic anomalies and their implications.

3.
J Contemp Brachytherapy ; 16(1): 6-11, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38584883

RESUMO

Purpose: Low-dose-rate (LDR) brachytherapy in young men remains controversial amongst urologists due to their concerns regarding long-term biochemical control and treatment-related toxicities. The purpose of this study was to evaluate the treatment outcomes of men under 60 years of age who underwent LDR brachytherapy with iodine-125 (125I) for clinically localized low- to intermediate-risk prostate cancer. Material and methods: All consecutive patients with clinically localized prostate cancer treated at our institution from 2003 to 2016 with 125I monotherapy were included in the study. Prescription dose was 145.0 Gy modified peripheral loading (MPD). All patients were assessed for biochemical progression-free survival using Phoenix definition (nadir +2 ng/ml), clinical progression-free survival, overall survival (OS), and any associated treatment toxicity. Results: A total of 161 patients were included, with a median follow-up of 6.8 years (range, 3-14.54 years). Median age at implant was 57 years (range, 53-59 years). Mean prostate specific antigen (PSA) level at diagnosis was 4.43 ng/ml (SD = 2.29). Majority of men had low-risk prostate cancer (70.2%). Biochemical progression-free survival at 8 years was 94% for the entire cohort. Median PSA at 4 years was 0.169 (IQR, 0.096-0.360), with 45% of patients having a PSA greater than 0.2. OS was 96.9%, with 5 deaths reported but only one was secondary to prostate cancer. Late grade > 2 genitourinary toxicities were reported in 18 patients (11.2%). Three patients (1.9%) developed secondary cancers, all considered unrelated to their LDR brachytherapy. Conclusions: With excellent long-term treatment outcomes and minimal associated toxicities, our results showed that LDR brachytherapy can be an effective treatment of choice in younger men.

4.
Nanoscale ; 16(4): 1952-1970, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38175178

RESUMO

The self-assembly and surface adsorption of glycerol monooleate (GMO) in n-dodecane are studied using a combination of experimental and molecular dynamics simulation techniques. The self-assembly of GMO to form reverse micelles, with and without added water, is studied using small-angle neutron scattering and simulations. A large-scale simulation is also used to investigate the self-assembly kinetics. GMO adsorption onto iron oxide is studied using depletion isotherms, neutron reflectometry, and simulations. The adsorbed amounts of GMO, and any added water, are determined experimentally, and the structures of the adsorbed films are investigated using reflectometry. Detailed fitting and analysis of the reflectometry measurements are presented, taking into account various factors such as surface roughness, and the presence of impurities. The reflectometry measurements are complemented by molecular dynamics simulations, and good consistency between both approaches is demonstrated by direct comparison of measured and simulated reflectivity and scattering length density profiles. The results of this analysis are that in dry systems, GMO adsorbs as self-assembled reverse micelles with some molecules adsorbing directly to the surface through the polar head groups, while in wet systems, the GMO is adsorbed onto a thin layer of water. Only at high surface coverage is some water trapped inside a reverse-micelle structure; at lower surface coverages, the GMO molecules associate primarily with the water layer, rather than self-assemble.

5.
J Appl Crystallogr ; 56(Pt 1): 12-17, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36777146

RESUMO

As a result of the availability of modern software and hardware, Bayesian analysis is becoming more popular in neutron and X-ray reflectometry analysis. The understandability and replicability of these analyses may be harmed by inconsistencies in how the probability distributions central to Bayesian methods are represented in the literature. Herein advice is provided on how to report the results of Bayesian analysis as applied to neutron and X-ray reflectometry. This includes the clear reporting of initial starting conditions, the prior probabilities, the results of any analysis and the posterior probabilities that are the Bayesian equivalent of the error bar, to enable replicability and improve understanding. It is believed that this advice, grounded in the authors' experience working in the field, will enable greater analytical reproducibility in the work of the reflectometry community, and improve the quality and usability of results.

6.
Langmuir ; 39(1): 668-678, 2023 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-36579816

RESUMO

The adsorption behavior of ß-nicotinamide adenine dinucleotide (NADH) at the carbon/electrolyte interface has been studied using a combination of neutron reflectometry (NR) and solution depletion isotherms. Coupling the NR technique with an electrochemical cell allowed in situ observation of the reversible adsorption and desorption of the molecule at the electrode surface over a range of applied potentials. The overall surface coverage was low (30-50%), suggesting adsorption only at specific defect sites on the surface. Isotherms conducted over a range of temperatures were used to extract thermodynamic parameters, which implied strong physisorption via electrostatic interactions. In addition, changes in the outermost layer of the carbon electrode were observed as the applied potential was varied, which were confirmed with ex situ X-ray reflectivity measurements (XRR). X-ray photoelectron spectroscopy (XPS) measurements of the carbon surface demonstrated the majority of carbon atoms were in an sp2 state.


Assuntos
Carbono , NAD , Coenzimas , Adsorção , Nêutrons , Eletrólitos
7.
Clin Nucl Med ; 48(1): 85-89, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36288618

RESUMO

ABSTRACT: Prostate cancer (PCa) is a multifaceted, heterogeneous disease (with 7 molecular subtypes), which can metastasize to common sites, such as bone, lymph nodes, liver, and lungs. However, with PSMA PET imaging, rare sites of metastasis are increasingly discovered. We report 5 cases of unusual metastases in patients with castrate-sensitive PCa: solitary right inguinal nodal metastasis, solitary abdominal wall metastasis, penile shaft metastases, solitary perineum metastasis, and pleural metastases. These cases further support the use of PSMA-PET imaging in PCa monitoring, with the ability to detect solitary, small volume, and rare sites of metastases, which may not be apparent on conventional imaging.


Assuntos
Carcinoma , Neoplasias da Próstata , Masculino , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Próstata/patologia , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Tomografia por Emissão de Pósitrons , Radioisótopos de Gálio
8.
Phys Chem Chem Phys ; 24(2): 797-806, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34927644

RESUMO

The spontaneous adsorption of graphene oxide (GO) sheets at the air-water interface is explored using X-ray reflectivity (XRR) measurements. As a pure aqueous dispersion, GO sheets do not spontaneously adsorb at the air-water interface due to their high negative surface potential (-60 mV) and hydrophilic functionality. However, when incorporated with surfactant molecules at optimal ratios and loadings, GO sheets can spontaneously be driven to the surface. It is hypothesised that surfactant molecules experience favourable attractive interactions with the surfaces of GO sheets, resulting in co-assembly that serves to render the sheets surface active. The GO/surfactant composites then collectively adsorb at the air-water interface, with XRR analysis suggesting an interfacial structure comprising surfactant tailgroups in air and GO/surfactant headgroups in water for a combined thickness of 30-40 Å, depending on the surfactant used. Addition of too much surfactant appears to inhibit GO surface adsorption by saturating the interface, and low loadings of GO/surfactant composites (even at optimal ratios) do not show significant adsorption indicating a partitioning effect. Lastly, surfactant chemistry is also a key factor dictating adsorption capacity of GO. The zwitterionic surfactant oleyl amidopropyl betaine causes marked increases in GO surface activity even at very low concentrations (≤0.2 mM), whereas non-ionic surfactants such as Triton X-100 and hexaethyleneglycol monododecyl ether require higher concentrations (ca. 1 mM) in order to impart spontaneous adsorption of the sheets. Anionic surfactants do not enhance GO surface activity presumably due to like-charge repulsions that prevent co-assembly. This work provides useful insight into the synergy between GO sheets and molecular amphiphiles in aqueous systems for enhancing the surface activity of GO, and can be used to inform system formulation for developing water-friendly, surface active composites based around atomically thin materials.

9.
Sci Rep ; 11(1): 9713, 2021 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-33958678

RESUMO

A novel neutron and X-ray reflectometry sample environment is presented for the study of surface-active molecules at solid-liquid interfaces under shear. Neutron reflectometry was successfully used to characterise the iron oxide-dodecane interface at a shear rate of [Formula: see text] [Formula: see text] using a combination of conventional reflectometry theory coupled with the summation of reflected intensities to describe reflectivity from thicker films. Additionally, the structure adopted by glycerol monooleate (GMO), an Organic Friction Modifier, when adsorbed at the iron oxide-dodecane interface at a shear rate of [Formula: see text] [Formula: see text] was studied. It was found that GMO forms a surface layer that appears unaltered by the effect of shear, where the thickness of the GMO layer was found to be [Formula: see text] Å under direct shear at [Formula: see text] [Formula: see text] and [Formula: see text] Å when not directly under shear. Finally, a model to analyse X-ray reflectometry data collected with the sample environment is also described and applied to data collected at [Formula: see text] [Formula: see text].

10.
J Chromatogr A ; 1639: 461914, 2021 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-33503524

RESUMO

Recent advances in process analytical technologies and modelling techniques present opportunities to improve industrial chromatography control strategies to enhance process robustness, increase productivity and move towards real-time release testing. This paper provides a critical overview of batch and continuous industrial chromatography control systems for therapeutic protein purification. Firstly, the limitations of conventional industrial fractionation control strategies using in-line UV spectroscopy and on-line HPLC are outlined. Following this, an evaluation of monitoring and control techniques showing promise within research, process development and manufacturing is provided. These novel control strategies combine rapid in-line data capture (e.g. NIR, MALS and variable pathlength UV) with enhanced process understanding obtained from mechanistic and empirical modelling techniques. Finally, a summary of the future states of industrial chromatography control systems is proposed, including strategies to control buffer formulation, product fractionation, column switching and column fouling. The implementation of these control systems improves process capabilities to fulfil product quality criteria as processes are scaled, transferred and operated, thus fast tracking the delivery of new medicines to market.


Assuntos
Cromatografia/métodos , Indústrias , Preparações Farmacêuticas , Análise Espectral
11.
Plast Reconstr Surg Glob Open ; 8(11): e3252, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33299715

RESUMO

Decubitus ulcers (DU) are a common pathology with significant morbidity and financial implications for health services globally. This study aimed to compare the burden of DU across European Union (EU) 15+ countries between 1990 and 2017. METHODS: Age-standardized incidence, mortality, and disability-adjusted life-years (DALYs) rates per 100,000 were extracted from the Global Burden of Disease Study online data repository for EU15+ countries (a group of 19 countries with comparable health expenditure, including the United States, Canada, the United Kingdom, and Australia). A joinpoint regression analysis was used to describe trends. RESULTS: The incidence of DU increased between 1990 and 2017 in 15 of 19 EU15+ countries for both men and women. Mortality from DU decreased over the time period analyzed in the majority of EU15+ countries: only in Denmark, Finland, and Germany were increasing mortality rates observed. Decreasing DALY rates were generally observed, with the largest decreases observed in Ireland for men and women. Denmark and Germany were the only countries to demonstrate unfavorable trends in mortality, incidence, and DALYs between 1990 and 2017 for men and women. The United States, the Netherlands, and France were the only EU15+ countries in which improving disease burden was identified between 1990 and 2017 for all parameters assessed. CONCLUSIONS: Incidence of DU is increasing in EU15+ countries, whereas mortality rates and DALYs are improving. The trends in disease burden in Denmark and Germany have followed contrasting and unfavorable trends. Investigation into these trends is called for.

12.
Biomacromolecules ; 21(11): 4569-4576, 2020 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-32597638

RESUMO

Spontaneous formation of vesicles from the self-assembly of two specific surfactants, one zwitterionic (oleyl amidopropyl betaine, OAPB) and the other anionic (Aerosol-OT, AOT), is explored in water using small-angle scattering techniques. Two factors were found to be critical in the formation of vesicles: surfactant ratio, as AOT concentrations less than equimolar with OAPB result in cylindrical micelles or mixtures of micellar structures, and salt concentration, whereby increasing the amount of NaCl promotes vesicle formation by reducing headgroup repulsions. Small-angle neutron scattering measurements reveal that the vesicles are approximately 30-40 nm in diameter, depending on sample composition. Small-angle X-ray scattering measurements suggest preferential partitioning of OAPB molecules on the vesicle inner layer to support vesicular packing. Heating the vesicles to physiological temperature (37 °C) causes them to collapse into smaller ellipsoidal micelles (2-3 nm), with higher salt concentrations (≥10 mM) inhibiting this transition. These aggregates could serve as responsive carriers for loading or unloading of aqueous cargoes such as drugs and pharmaceuticals, with temperature changes serving as a simple release/uptake mechanism.


Assuntos
Micelas , Tensoativos , Ânions , Betaína , Espalhamento a Baixo Ângulo
14.
Burns ; 46(3): 514-519, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31230799

RESUMO

A rise in the current trend of corrosive substance attacks have been reported in the UK, causing devastating effects on victims. The optimal management of these patients requires the specialist skills of the burn multidisciplinary team (MDT) to address the resulting physical and psychological trauma experienced. However, burn care must commence in the pre-hospital setting. The public and first responders are invaluable resources in helping to limit the adverse effects of burns. Challenges of burn care outside the Burns Unit are not limited to the treatment of the injured patient and the rehabilitation of survivors. These challenges also encompass better education of the public and allied health professionals, as well as planning strategies to reduce the incidence of acid attacks. Prevention is always better than cure. This paper discusses the broadening of the MDT to improve outcomes in acid attacks by exploring the wider roles of the public, media, emergency services, police, legislation and better education.


Assuntos
Queimaduras Químicas/terapia , Cáusticos/toxicidade , Primeiros Socorros , Violência , Pessoal Técnico de Saúde , Queimaduras Químicas/fisiopatologia , Queimaduras Químicas/psicologia , Violência Doméstica , Serviços Médicos de Emergência , Socorristas , Educação em Saúde , Humanos , Meios de Comunicação de Massa , Equipe de Assistência ao Paciente , Racismo , Reino Unido , Violência/prevenção & controle
16.
Br J Hosp Med (Lond) ; 78(7): 402-406, 2017 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-28692361

RESUMO

A recent shift towards more collective leadership in the NHS can help to achieve a culture of safety, particularly through encouraging frontline staff to participate and take responsibility for improving safety through learning from error and near misses. Leaders must ensure that they provide psychological safety, organizational fairness and learning systems for staff to feel confident in raising concerns, that they have the autonomy and skills to lead continual improvement, and that they have responsibility for spreading this learning within and across organizations.


Assuntos
Aprendizagem , Erros Médicos , Segurança do Paciente , Medicina Estatal/organização & administração , Humanos , Liderança , Cultura Organizacional , Autonomia Profissional , Segurança , Reino Unido
17.
Artigo em Inglês | MEDLINE | ID: mdl-26734266

RESUMO

A Trust level audit demonstrated that the trauma and orthopaedic department did not reach its own standards in adhering to Trust antibiotic prescribing guidelines. Junior doctors are the main prescribers of antibiotics during inpatient stays. Local policy states that for all inpatients on antibiotics, the start date, duration, and indication for antibiotics must be documented on the drug card. Each patient drug card was reviewed by the department pharmacist and it was recorded whether the documentation was in line with Trust policy. A monthly league table, coined 'The Champions League', was created. It was published monthly and displayed in the doctors' office and other clinical areas to highlight which doctors had or had not adhered to the prescribing guidelines. In August 2012 the monthly audit for the trauma and orthopaedic department included 74 patients. The total number of antibiotic courses prescribed was 28; of these courses only 15 (53.5%) had an indication documented and 15 (53.5%) had a review/stop date documented. In December 2012, after two published league tables, 61 patients were reviewed. A total of 19 antibiotic courses were prescribed; 18 (94.7%) had the indication documented and 16 (84.2%) had the review/stop date documented. The standards of prescribing improved within the department and good prescribing practice became ingrained into each doctor's practice. The league table proved to be a novel tool that helped to raise the profile of antibiotic prescribing and change doctor prescribing habits. It created a competitive spirit within the department which improved morale. Doctors responded positively to feedback if they were not achieving the desirable standards, and enjoyed the challenge of improving the standard of prescribing.

18.
Case Rep Pediatr ; 2013: 649097, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23997974

RESUMO

Study Design. A Case Report. Objective. We present a 15-year-old girl with an acute atypical scoliosis secondary to chronic recurrent multifocal osteomyelitis (CRMO). Summary of Background Data. CRMO is a rare nonpyogenic inflammatory bone condition with unclear aetiology. CRMO mainly affects the metaphyses of long bones, the pelvis, shoulder girdle, and less commonly the spine. Methods. Our case presented with a 6-month history of worsening thoracic back pain, asymmetry of her shoulders and abnormal posture. Whole spine radiographs revealed a right atypical thoracic scoliosis. Magnetic Resonance Imaging showed abnormal signal on the short TI inversion recovery (STIR) sequences in multiple vertebrae. A bone biopsy demonstrated evidence of fibrosis and chronic inflammatory changes. Interval MRI scans revealed new oedematous lesions and disappearance of old lesions. Symptoms improved. Results. It is important to consider CRMO as an acute cause of atypical scoliosis. Malignancy, pyogenic infections and atypical presentations of juvenile arthritis need excluding. Conclusion. This 24-month follow-up describes a rare cause of an atypical scoliosis and fortifies the small amount of the currently available literature. The case highlights the relapsing and remitting nature of CRMO with new lesions developing and older lesions burning out. We advise close radiological surveillance and symptomatic management.

19.
Artigo em Inglês | MEDLINE | ID: mdl-26734157

RESUMO

Discharge summaries document key information after an in-patient care episode and hand back care to the GP. Locally our orthopaedic department used carbon-copy paper as a discharge document. Anecdotally, these were thought to be inaccurate, illegible and of poor quality. Complaints from GPs became a catalyst in assessing the accuracy and presenting it to the department. A baseline dataset of inaccuracies was collected. This became a good starting point to develop a new improved system of discharging orthopaedic patients. We proposed to develop a bespoke, electronic, patient centred discharge document. Our aims were to improve patient safety, quality and develop an adaptable document, which could be updated to be in line with local CQUINs. The initial challenges of the resistance to change within the department were overcome by presenting data in an open forum with an agreed trial period. A multidisciplinary team was formed, including managers, consultants, junior doctors, allied health professionals and IT personnel. This facilitated live decision making, streamlining the processes. We created an adaptable online document, which enabled regular updates. This in-turn improved the overall accuracy of the document, improved prescription of key medications and ensured we were able to fulfil local CQUINs. We highly recommend the use of subspecialty specific electronic discharge summaries.

20.
Free Radic Res ; 45(9): 991-9, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21696323

RESUMO

Elevated oxidative stress can alter the function of proteins through the reversible oxidation of the thiol groups of key cysteine residues. This study evaluated a method to scan for reversible protein thiol oxidation in tissue by measuring reduced and oxidized protein thiols. It assessed the responsiveness of protein thiols to oxidative stress in vivo using a dystrophic (mdx) mouse model and compared the changes to commonly used oxidative biomarkers. In mdx mice, protein thiol oxidation was significantly elevated in the diaphragm, gastrocnemius and quadriceps muscles. Neither malondialdehyde nor degree of glutathione oxidation was elevated in mdx muscles. Protein carbonyl content was elevated, but changes in protein carbonyl did not reflect changes in protein thiol oxidation. Collectively, these data indicate that where there is an interest in protein thiol oxidation as a mechanism to cause or exacerbate pathology, the direct measurement of protein thiols in tissue would be the most appropriate screening tool.


Assuntos
Cisteína/metabolismo , Músculo Esquelético/metabolismo , Estresse Oxidativo , Proteínas/metabolismo , Compostos de Sulfidrila/metabolismo , Animais , Glutationa/metabolismo , Peroxidação de Lipídeos , Masculino , Malondialdeído/análise , Malondialdeído/sangue , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos mdx , Distrofia Muscular de Duchenne/metabolismo , Oxirredução , Carbonilação Proteica , Proteínas/química
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