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1.
Scand J Immunol ; 91(1): e12839, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31630416

RESUMO

The humanized IgG1κ monoclonal antibody siplizumab and its rat parent monoclonal IgG2b antibody BTI-322 are directed against the CD2 antigen. Siplizumab is species-specific, reacting with human and chimpanzee cells but not with cells from any other species, including other non-human primates. Because siplizumab treatment has recently shown great potential in clinical transplantation, we now present the results of our previous pharmacokinetic, pharmacodynamic and safety studies of both antibodies. Fourteen chimpanzees received 1-3 doses of 0.143 to 5.0 mg/kg iv The effects were followed with flow cytometry on peripheral lymphocytes and staining of lymph nodes. Side effects were recorded. Serum antibody concentrations were followed. Across the doses, a rapid, transient depletion of CD2, CD3, CD4 and CD8 lymphocytes and NK cells was observed for both antibodies. Immune reconstitution was more rapid for BTI-322 compared to siplizumab. Paracortical lymph node T cell depletion was moderate, estimated at 45% with doses of >0.6 mg/kg. Restoration of lymph node architecture was seen after two weeks to two months for all animals. All four subjects receiving BTI-322 experienced AEs on the first dosing day, while the eight subjects dosed with siplizumab experienced few mild, transient AEs. Infusion with siplizumab and BTI-322 resulted in rapid depletion of CD2+ cells in circulation and tissue. Siplizumab had a longer t1/2 and fewer AEs compared to BTI-322.


Assuntos
Anticorpos Monoclonais/farmacocinética , Antígenos CD2/antagonistas & inibidores , Animais , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados/farmacocinética , Anticorpos Monoclonais Humanizados/uso terapêutico , Biomarcadores , Biópsia , Citocinas/sangue , Feminino , Imunoglobulina G/administração & dosagem , Imunoglobulina G/farmacologia , Imunofenotipagem , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Depleção Linfocítica , Linfócitos/imunologia , Linfócitos/metabolismo , Masculino , Pan troglodytes , Ratos
2.
Curr Top Microbiol Immunol ; 366: 37-47, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22976349

RESUMO

Bovine spongiform encephalopathy (BSE) is a protein misfolding disease of cattle which belongs to the group of transmissible spongiform encephalopathies (TSEs) or prion diseases. This group also includes scrapie in sheep and goats, chronic wasting disease (CWD) of cervids and Creutzfeldt-Jakob disease (CJD) humans. The first case of BSE was recognised in England in 1986 as a progressive, neurological condition where affected animals behaved abnormally, exhibited anxiety, ataxia, hypersensitivity to touch and noise and poor body condition. Spongiform change was observed in the brain stem of cattle at post-mortem and its similarity to scrapie in sheep stimulated biochemical investigation and transmission studies which confirmed it as a novel prion disease of cattle. Epidemiological analysis of the initial cases of disease implicated a common extended source of infection, likely to be related to feed, and stimulated a series of control measures designed to restrict feeding of mammalian-derived protein to ruminants in various parts of the United Kingdom and to prevent the use of various bovine offals in feed or food production. This article outlines the rise and fall of the incidence of BSE in the UK and Europe, its classification as a zoonotic disease with the emergence of variant CJD, the implications of it as a prion disease and challenge its diagnosis and control continues to represent worldwide.


Assuntos
Encefalopatia Espongiforme Bovina/epidemiologia , Inocuidade dos Alimentos , Saúde Global , Animais , Bovinos , Encefalopatia Espongiforme Bovina/prevenção & controle , Humanos , Ovinos
3.
Sci Rep ; 14(1): 6573, 2024 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-38503790

RESUMO

The COVID-19 pandemic has precipitated a global mental health crisis, with a particularly pronounced impact on the entrepreneurial sector. This paper presents a comparative analysis of mental health challenges among entrepreneurs in China during the pandemic, with a specific focus on attention deficit hyperactivity disorder (ADHD) and Dyslexia. The study assesses the prevalence of ADHD and dyslexia symptoms among established and emerging entrepreneurs in China, finding notable occurrences within this group. The research also examines the self-care practices of these entrepreneurs, shedding light on their approaches during the pandemic period. The findings highlight a complex interplay between mental health issues and entrepreneurial activities, suggesting that certain ADHD and dyslexia traits may offer unexpected benefits in the entrepreneurial realm. These insights are critical for developing supportive frameworks that leverage the strengths of neurodiverse entrepreneurs while mitigating associated challenges, especially in a post-pandemic economic landscape. The study concludes with policy and practice recommendations to bolster the wellbeing and resilience of entrepreneurs facing the multifaceted impacts of the pandemic.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , COVID-19 , Dislexia , Humanos , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , COVID-19/epidemiologia , Saúde Mental , Pandemias , Dislexia/psicologia , China/epidemiologia
4.
Emerg Infect Dis ; 19(11): 1731-9, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24188521

RESUMO

Public and animal health controls to limit human exposure to animal prions are focused on bovine spongiform encephalopathy (BSE), but other prion strains in ruminants may also have zoonotic potential. One example is atypical/Nor98 scrapie, which evaded statutory diagnostic methods worldwide until the early 2000s. To investigate whether sheep infected with scrapie prions could be another source of infection, we inoculated transgenic mice that overexpressed human prion protein with brain tissue from sheep with natural field cases of classical and atypical scrapie, sheep with experimental BSE, and cattle with BSE. We found that these mice were susceptible to BSE prions, but disease did not develop after prolonged postinoculation periods when mice were inoculated with classical or atypical scrapie prions. These data are consistent with the conclusion that prion disease is less likely to develop in humans after exposure to naturally occurring prions of sheep than after exposure to epizootic BSE prions of ruminants.


Assuntos
Expressão Gênica , Príons/genética , Scrapie/genética , Scrapie/transmissão , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Bovinos , Encefalopatia Espongiforme Bovina/metabolismo , Encefalopatia Espongiforme Bovina/patologia , Humanos , Camundongos , Camundongos Transgênicos , Príons/metabolismo , Ovinos , Especificidade da Espécie
5.
Anal Biochem ; 436(1): 36-44, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23357236

RESUMO

Prions are proteins that can exist in two (or more) folding states, a normal or cellular form and a series of infectious or prion forms, which are prone to aggregate. The prion form can induce conversion of the cellular form and so transmit phenotypic effects of this structural rearrangement within and between cells and organisms. The conversion of PrP(C), the mammalian prion glycoprotein, to its prion form, PrP(Sc), in the brain is a precursor to progressive neurological degeneration, and the various folded forms of PrP(Sc) (defined by the size and glycosylation of protease-resistant core peptides of the PrP aggregates, PrP(res)) are characteristic of a particular neurodegenerative phenotype or prion disease. Here, quantitative multiplex mass spectrometry was used for N-terminal amino acid profiling (N-TAAP) of PrP(res) from sheep affected by scrapie, the prion disease of small ruminants, to rapidly assess the diversity of prions within particular flocks. In 29 cases, PrP(res) concentrations varied from below the limit of detection (350 fmol/g) to 15 pmol/g wet brain. Although most had a single N-TAAP profile, two novel variants were identified: one common to the ARH/ARQ animals in this study and one in an animal of the wild-type sheep PrP genotype (ARQ/ARQ).


Assuntos
Proteínas PrPSc/análise , Sequência de Aminoácidos , Animais , Encéfalo , Cromatografia Líquida de Alta Pressão , Genótipo , Limite de Detecção , Espectrometria de Massas , Dados de Sequência Molecular , Proteínas PrPSc/química , Proteínas PrPSc/genética , Scrapie/genética , Scrapie/metabolismo , Análise de Sequência de Proteína , Ovinos
6.
Comput Biol Med ; 165: 107463, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37699322

RESUMO

Computational models enable a safe and convenient way to study the excitation of nerve fibers under external stimulation. Contemporary models calculate the electric field distribution from transcutaneous stimulation and the resulting neuronal response separately. This study uses finite element methods to develop a multi-scale model that couples electric fields within macroscopic tissue layers and microscopic nerve fibers in a single-stage computational framework. The model included a triaxial myelinated nerve fiber bundle embedded within a volume conductor of tissue layers to represent the median nerve innervating the forearm muscles. The model captured the excitability of nerve fibers under transcutaneous stimulation and their nerve-tissue interactions to a transient external stimulus. The determinants of the strength-duration curve, rheobase, and chronaxie for the proposed model had close correlations with in-vivo experimentation on human participants. Additionally, the excitability indices for the triaxial myelinated nerve fiber implemented using the finite element method agreed well with experimental data from the literature. The validity of the proposed model encourages its use for applications involving transcutaneous stimulation. Capable of capturing field distribution across realistic morphologies, the model can serve as a testbed to improve stimulation protocols and electrode designs with subject-level specificity.


Assuntos
Axônios , Manejo da Dor , Humanos , Fibras Nervosas Mielinizadas , Eletrodos , Antebraço
7.
ACS Omega ; 8(30): 26650-26662, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37546595

RESUMO

The development of self-healing materials has gained significance in the medical field to enhance the longevity and reliability of medical devices and implants. Material degradation caused by mechanical stress, environmental factors, and damage during use can lead to failure and necessitate manual inspection and maintenance. Self-healing materials, including polymers and elastomers, offer a promising solution by activating microdamage repair mechanisms. Polyurea coatings, known for their durability, flexibility, and versatility, have found widespread applications in various industries to prevent corrosion and abrasion and impact damage. This review focuses on the self-healing capability of polyurethane coatings and the efficacy of fabricated microcapsules. Experimental results elucidate the necessary conditions for achieving self-healing in polyurethane coatings encapsulated with suitable healing agents. These factors directly impact the self-healing potential of polyurea coatings and provide insights for medical device manufacturers seeking optimal coatings. The report also discusses challenges in fabrication and sample preparation, along with limitations of the project and recommendations for future research.

8.
ACS Appl Bio Mater ; 6(8): 3213-3220, 2023 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-37428894

RESUMO

Biofilm formation and growth is a significant concern for water treatment professionals, as it can lead to the contamination of water systems and pose a threat to public health. Biofilms are complex communities of microorganisms that adhere to surfaces and are embedded in an extracellular matrix of polysaccharides and proteins. They are notoriously difficult to control, as they provide a protective environment for bacteria, viruses, and other harmful organisms to grow and proliferate. This review article highlights some of the factors that favor biofilm growth, as well as various strategies for controlling biofilm in water systems. Adopting the best available technologies, such as wellhead protection programs, proper industrial cooling water system maintenance, and filtration and disinfection, can prevent the formation and growth of biofilms in water systems. A comprehensive and multifaceted approach to biofilm control can reduce the occurrence of biofilms and ensure the delivery of high-quality water to the industrial process.


Assuntos
Biofilmes , Purificação da Água , Bactérias , Desinfecção
9.
bioRxiv ; 2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37333228

RESUMO

Complex behaviors are mediated by neural computations occurring throughout the brain. In recent years, tremendous progress has been made in developing technologies that can record neural activity at cellular resolution at multiple spatial and temporal scales. However, these technologies are primarily designed for studying the mammalian brain during head fixation - wherein the behavior of the animal is highly constrained. Miniaturized devices for studying neural activity in freely behaving animals are largely confined to recording from small brain regions owing to performance limitations. We present a cranial exoskeleton that assists mice in maneuvering neural recording headstages that are orders of magnitude larger and heavier than the mice, while they navigate physical behavioral environments. Force sensors embedded within the headstage are used to detect the mouse's milli-Newton scale cranial forces which then control the x, y, and yaw motion of the exoskeleton via an admittance controller. We discovered optimal controller tuning parameters that enable mice to locomote at physiologically realistic velocities and accelerations while maintaining natural walking gait. Mice maneuvering headstages weighing up to 1.5 kg can make turns, navigate 2D arenas, and perform a navigational decision-making task with the same performance as when freely behaving. We designed an imaging headstage and an electrophysiology headstage for the cranial exoskeleton to record brain-wide neural activity in mice navigating 2D arenas. The imaging headstage enabled recordings of Ca2+ activity of 1000s of neurons distributed across the dorsal cortex. The electrophysiology headstage supported independent control of up to 4 silicon probes, enabling simultaneous recordings from 100s of neurons across multiple brain regions and multiple days. Cranial exoskeletons provide flexible platforms for largescale neural recording during the exploration of physical spaces, a critical new paradigm for unraveling the brain-wide neural mechanisms that control complex behavior.

10.
Res Sq ; 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-38014260

RESUMO

Complex behaviors are mediated by neural computations occurring throughout the brain. In recent years, tremendous progress has been made in developing technologies that can record neural activity at cellular resolution at multiple spatial and temporal scales. However, these technologies are primarily designed for studying the mammalian brain during head fixation - wherein the behavior of the animal is highly constrained. Miniaturized devices for studying neural activity in freely behaving animals are largely confined to recording from small brain regions owing to performance limitations. We present a cranial exoskeleton that assists mice in maneuvering neural recording headstages that are orders of magnitude larger and heavier than the mice, while they navigate physical behavioral environments. Force sensors embedded within the headstage are used to detect the mouse's milli-Newton scale cranial forces which then control the x, y, and yaw motion of the exoskeleton via an admittance controller. We discovered optimal controller tuning parameters that enable mice to locomote at physiologically realistic velocities and accelerations while maintaining natural walking gait. Mice maneuvering headstages weighing up to 1.5 kg can make turns, navigate 2D arenas, and perform a navigational decision-making task with the same performance as when freely behaving. We designed an imaging headstage and an electrophysiology headstage for the cranial exoskeleton to record brain-wide neural activity in mice navigating 2D arenas. The imaging headstage enabled recordings of Ca2+ activity of 1000s of neurons distributed across the dorsal cortex. The electrophysiology headstage supported independent control of up to 4 silicon probes, enabling simultaneous recordings from 100s of neurons across multiple brain regions and multiple days. Cranial exoskeletons provide flexible platforms for largescale neural recording during the exploration of physical spaces, a critical new paradigm for unraveling the brain-wide neural mechanisms that control complex behavior.

11.
J Gen Virol ; 91(Pt 8): 2132-2138, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20392900

RESUMO

Twenty-four atypical scrapie cases from sheep with different prion protein genotypes from Great Britain were transmitted to transgenic tg338 and/or TgshpXI mice expressing sheep PrP alleles, but failed to transmit to wild-type mice. Mean incubation periods were 200-300 days in tg338 mice and 300-500 days in TgshpXI mice. Survival times in C57BL/6 and VM/Dk mice were >700 days. Western blot analysis of mouse brain samples revealed similar multi-band, protease-resistant prion protein (PrP(res)) profiles, including an unglycosylated band at approximately 8-11 kDa, which was shown by antibody mapping to correspond to the approximately 93-148 aa portion of the PrP molecule. In transgenic mice, the incubation periods, Western blot PrP(res) profiles, brain lesion profiles and abnormal PrP (PrP(Sc)) distribution patterns produced by the Great Britain atypical scrapie isolates were similar and compatible with the biological characteristics of other European atypical scrapie or Nor98 cases.


Assuntos
Scrapie/transmissão , Doenças dos Ovinos/transmissão , Animais , Western Blotting , Encéfalo/patologia , Histocitoquímica , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Peso Molecular , Príons/química , Príons/isolamento & purificação , Ovinos , Análise de Sobrevida , Reino Unido
12.
Biotechnol Bioeng ; 106(1): 57-67, 2010 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-20073088

RESUMO

With increasing timeline pressures to get therapeutic and vaccine candidates into the clinic, resource intensive approaches such as the use of shake flasks and bench-top bioreactors may limit the design space for experimentation to yield highly productive processes. The need to conduct large numbers of experiments has resulted in the use of miniaturized high-throughput (HT) technology for process development. One such high-throughput system is the SimCell platform, a robotically driven, cell culture bioreactor system developed by BioProcessors Corp. This study describes the use of the SimCell micro-bioreactor technology for fed-batch cultivation of a GS-CHO transfectant expressing a model IgG4 monoclonal antibody. Cultivations were conducted in gas-permeable chambers based on a micro-fluidic design, with six micro-bioreactors (MBs) per micro-bioreactor array (MBA). Online, non-invasive measurement of total cell density, pH and dissolved oxygen (DO) was performed. One hundred fourteen parallel MBs (19 MBAs) were employed to examine process reproducibility and scalability at shake flask, 3- and 100-L bioreactor scales. The results of the study demonstrate that the SimCell platform operated under fed-batch conditions could support viable cell concentrations up to least 12 x 10(6) cells/mL. In addition, both intra-MB (MB to MB) as well as intra-MBA (MBA to MBA) culture performance was found to be highly reproducible. The intra-MB and -MBA variability was calculated for each measurement as the coefficient of variation defined as CV (%) = (standard deviation/mean) x 100. The % CV values for most intra-MB and intra-MBA measurements were generally under 10% and the intra-MBA values were slightly lower than those for intra-MB. Cell growth, process parameters, metabolic and protein titer profiles were also compared to those from shake flask, bench-top, and pilot scale bioreactor cultivations and found to be within +/-20% of the historical averages.


Assuntos
Biotecnologia/métodos , Animais , Reatores Biológicos , Células CHO , Técnicas de Cultura de Células/métodos , Cricetinae , Cricetulus , Imunoglobulina G/biossíntese , Proteínas Recombinantes/biossíntese , Reprodutibilidade dos Testes
13.
Physiol Meas ; 41(10): 10NT01, 2020 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-33045694

RESUMO

OBJECTIVE: To determine how increased excitability from subthreshold currents would alter neural activity as it propagates through the subthreshold currents. APPROACH: Experiments were performed on two Romney cross-breed sheep in vivo, by applying subthreshold currents either at the stimulus site or between the stimulus and recording sites. Neural recordings were obtained from nerve cuff implanted on the peroneal or sciatic nerve branches, while stimulus was applied to either the peroneal nerve or pins placed through the lower hindshank. MAIN RESULTS: Showed that subthreshold currents applied to the same site as stimulus increased excitation of underlying nerve fibres (p < 0.005). With stimulus and subthreshold currents applied to different sites on the peroneal nerve, the primary compound action potential (CAP) in the sciatic displayed a temporal shift of -2.5 to -3 µs which agreed with changes observed in the CAP waveform (p > 0.05). SIGNIFICANCE: These findings contribute to the understanding of mechanisms in myelinated fibres of subthreshold current neuromodulation therapies.


Assuntos
Fibras Nervosas , Nervos Periféricos , Potenciais de Ação , Animais , Fibras Nervosas/fisiologia , Nervos Periféricos/fisiologia , Nervo Fibular , Nervo Isquiático , Ovinos
14.
Handb Clin Neurol ; 153: 121-134, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29887132

RESUMO

This chapter describes the prion diseases of cattle, or bovine transmissible spongiform encephalopathies (BoTSEs). "Classic" bovine spongiform encephalopathy (C-BSE), the major prion protein disorder of Bovidae, was first described in 1986. We also describe the spatiotemporal correlation of C-BSE to a novel form of human prion disease, variant Creutzfeldt-Jakob disease (vCJD), which led to the classification of BSE as a zoonotic disease (and the "cause" of vCJD) in 1996. From isolated cases first identified retrospectively in May 1985, a major bovine spongiform encephalopathy (BSE) epidemic peaked within the British Isles in 1991, and has so far led to over 195,000 confirmed cases in cattle, and several thousand more cases within Europe and a few elsewhere. By 2017, the disease had been essentially eradicated below the level of surveillance detection in Europe, although sporadic cases are still predicted to show up for several years to come. By 2004, other forms of BSE, H-type and L-type, had been recognized and, in the absence of information to the contrary, are also included in the classification of BSE as a zoonotic prion disease of bovine origin. This chapter aims to cover the clinical, epidemiologic, neuropathologic, biochemical, biomarker, and pathogenetic aspects of the bovine prion disease and gives a brief, but important, description of the surveillance of BSE and other animal TSEs in Europe.


Assuntos
Encefalopatia Espongiforme Bovina , Monitoramento Epidemiológico , Animais , Bovinos , Encefalopatia Espongiforme Bovina/diagnóstico , Encefalopatia Espongiforme Bovina/epidemiologia , Encefalopatia Espongiforme Bovina/patologia , Humanos
15.
J Biomed Opt ; 23(11): 1-14, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30392195

RESUMO

We apply three optical coherence tomography (OCT) image analysis techniques to extract morphometric information from OCT images obtained on peripheral nerves of rat. The accuracy of each technique is evaluated against histological measurements accurate to + / - 1 µm. The three OCT techniques are: (1) average depth-resolved profile (ADRP), (2) autoregressive spectral estimation (AR-SE), and (3) correlation of the derivative spectral estimation (CoD-SE). We introduce a scanning window to the ADRP technique, which provides transverse resolution and improves epineurium thickness estimates-with the number of analyzed images showing agreement with histology increasing from 2 / 10 to 5 / 10 (Kruskal-Wallis test, α = 0.05). A method of estimating epineurium thickness, using the AR-SE technique, showed agreement with histology in 6 / 10 analyzed images (Kruskal-Wallis test, α = 0.05). Using a tissue sample in which histology identified two fascicles with an estimated difference in mean fiber diameter of 4 µm, the AR-SE and CoD-SE techniques both correctly identified the fascicle with larger fiber diameter distribution but incorrectly estimated the magnitude of this difference as 0.5 µm. The ability of the OCT signal analysis techniques to extract accurate morphometric details from peripheral nerves is promising but restricted in depth by scattering in adipose and neural tissues.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Nervo Isquiático/diagnóstico por imagem , Tomografia de Coerência Óptica/métodos , Tecido Adiposo/diagnóstico por imagem , Algoritmos , Animais , Técnicas Histológicas , Masculino , Imagens de Fantasmas , Ratos , Ratos Wistar
16.
J Neurol Sci ; 386: 4-11, 2018 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-29406965

RESUMO

The epizootic prion disease of cattle, bovine spongiform encephalopathy (BSE), causes variant Creutzfeldt-Jakob disease (vCJD) in humans following dietary exposure. While it is assumed that all cases of vCJD attributed to a dietary aetiology are related to cattle BSE, sheep and goats are susceptible to experimental oral challenge with cattle BSE prions and farmed animals in the UK were undoubtedly exposed to BSE-contaminated meat and bone meal during the late 1980s and early 1990s. Although no natural field cases of sheep BSE have been identified, it cannot be excluded that some BSE-infected sheep might have entered the European human food chain. Evaluation of the zoonotic potential of sheep BSE prions has been addressed by examining the transmission properties of experimental brain isolates in transgenic mice that express human prion protein, however to-date there have been relatively few studies. Here we report that serial passage of experimental sheep BSE prions in transgenic mice expressing human prion protein with methionine at residue 129 produces the vCJD phenotype that mirrors that seen when the same mice are challenged with vCJD prions from patient brain. These findings are congruent with those reported previously by another laboratory, and thereby strongly reinforce the view that sheep BSE prions could have acted as a causal agent of vCJD within Europe.


Assuntos
Encéfalo/metabolismo , Síndrome de Creutzfeldt-Jakob , Proteínas Priônicas/metabolismo , Príons/metabolismo , Fatores Etários , Animais , Síndrome de Creutzfeldt-Jakob/genética , Síndrome de Creutzfeldt-Jakob/patologia , Síndrome de Creutzfeldt-Jakob/transmissão , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica/genética , Humanos , Camundongos , Camundongos Transgênicos , Fenótipo , Proteínas Priônicas/genética , Ovinos
17.
Trials ; 19(1): 53, 2018 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-29351792

RESUMO

BACKGROUND: Randomised controlled trials (RCT) can struggle to recruit to target on time. This is especially the case with hard to reach populations such as those with severe mental ill health. The SCIMITAR+ trial, a trial of a bespoke smoking cessation intervention for people with severe mental ill health achieved their recruitment ahead of time and target. This article reports strategies that helped us to achieve this with the aim of aiding others recruiting from similar populations. METHODS: SCIMITAR+ is a multi-centre pragmatic two-arm parallel-group RCT, which aimed to recruit 400 participants with severe mental ill health who smoke and would like to cut down or quit. The study recruited primarily in secondary care through community mental health teams and psychiatrists with a smaller number of participants recruited through primary care. Recruitment opened in October 2015 and closed in December 2016, by which point 526 participants had been recruited. We gathered information from recruiting sites on strategies which led to the successful recruitment in SCIMITAR+ and in this article present our approach to trial management along with the strategies employed by the recruiting sites. RESULTS: Alongside having a dedicated trial manager and trial management team, we identified three main themes that led to successful recruitment. These were: clinicians with a positive attitude to research; researchers and clinicians working together; and the use of NHS targets. The overriding theme was the importance of relationships between both the researchers and the recruiting clinicians and the recruiting clinicians and the participants. CONCLUSIONS: This study makes a significant contribution to the limited evidence base of real-world cases of successful recruitment to RCTs and offers practical guidance to those planning and conducting trials. Building positive relationships between clinicians, researchers and participants is crucial to successful recruitment.


Assuntos
Transtornos Mentais/psicologia , Saúde Mental , Seleção de Pacientes , Fumantes/psicologia , Abandono do Hábito de Fumar/psicologia , Fumar/psicologia , Atitude do Pessoal de Saúde , Comportamento Cooperativo , Inglaterra , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Comunicação Interdisciplinar , Transtornos Mentais/diagnóstico , Médicos/psicologia , Pesquisadores/psicologia , Tamanho da Amostra , Fumar/efeitos adversos , Fatores de Tempo
18.
Prion ; 11(6): 405-414, 2017 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-29098930

RESUMO

M2B cells with persistent classical bovine spongiform encephalopathy (C-BSE) have been established previously. In this study, we performed strain characterization of the M2B cell line in bovine PrPC overexpressing mice (Tg 1896). Mice intracranially inoculated with M2B cells and C-BSE survived for 451 ± 7 and 465 ± 31 d post inoculation, respectively. Although biochemical properties, including deglycosylation and conformational stability, differed between M2B cells and C-BSE, inoculation with M2B cell lysate and C-BSE resulted in comparable phenotypes. Comparable vacuolation scores and PrPSc depositions were observed in the brain of Tg 1896 inoculated with both M2B cell lysate and C-BSE. Our results show that biochemical and biological characteristics of M2B cells and C-BSE are classifiable in the same strain.


Assuntos
Bioensaio/métodos , Encefalopatia Espongiforme Bovina/metabolismo , Proteínas Priônicas/metabolismo , Animais , Bovinos , Linhagem Celular , Camundongos , Camundongos Transgênicos , Proteínas PrPSc/metabolismo
19.
J Mol Biol ; 343(2): 467-76, 2004 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-15451674

RESUMO

The aqueous solution structure of the full-length recombinant ovine prion protein PrP(25-233), together with that of the N-terminal truncated version PrP(94-233), have been studied using vibrational Raman optical activity (ROA) and ultraviolet circular dichroism (UVCD). A sharp positive band at approximately 1315 cm(-1) characteristic of poly(L-proline) II (PPII) helix that is present in the ROA spectrum of the full-length protein is absent from that of the truncated protein, together with bands characteristic of beta-turns. Although it is not possible similarly to identify PPII helix in the full-length protein directly from its UVCD spectrum, subtraction of the UVCD spectrum of PrP(94-233) from that of PrP(25-233) yields a difference UVCD spectrum also characteristic of PPII structure and very similar to the UVCD spectrum of murine PrP(25-113). These results provide confirmation that a major conformational element in the N-terminal region is PPII helix, but in addition show that the PPII structure is interspersed with beta-turns and that little PPII structure is present in PrP(94-233). A principal component analysis of the ROA data indicates that the alpha-helix and beta-sheet content, located in the structured C-terminal domain, of the full-length and truncated proteins are similar. The flexibility imparted by the high PPII content of the N-terminal domain region may be an essential factor in the function and possibly also the misfunction of prion proteins.


Assuntos
Príons/química , Prolina/química , Estrutura Secundária de Proteína , Análise Espectral Raman , Sequência de Aminoácidos , Animais , Dicroísmo Circular/métodos , Modelos Moleculares , Dados de Sequência Molecular , Príons/genética , Príons/metabolismo , Prolina/metabolismo , Estrutura Terciária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Ovinos
20.
Transplantation ; 80(9): 1186-93, 2005 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-16314784

RESUMO

BACKGROUND: Blockade of costimulation and adhesion signaling is an attractive approach to interfere with graft rejection METHODS: Between January 1997 and May 1999, forty adults having benign liver diseases were included in a prospective, randomized study comparing tacrolimus plus low-dose short-term steroids without (n=20, TAC group) or with a 10-day course of antihuman CD2 monoclonal antibody (n=20, BTI group). RESULTS: At day 7, histological rejection expressed by mean Banff scores (2.3+/-1.6 vs. 5.4+/-1.6 in the TAC group; P<0.0001) and incidence of moderate to severe rejection (score>or=6) (0 vs. 10 [50%] in the TAC group; P<0.001) were significantly lower in the BTI group. Rejection was treated in 10% (two patients) of BTI patients during the first 3 months and in 15% during the whole follow-up and in 25% (five patients) of TAC patients (P=NS). None of the BTI-patients presented with an adverse event. Three-month, 1-year, and 5-year actual patient survival rates were 100%, 95%, and 95% in the BTI group and 100%, 100%, and 85% in the TAC group. Graft survival rates were 100%, 90%, and 90% in the BTI group and 95%, 95%, and 80% in the TAC group (P=NS). The mAb had no negative impact on infectious or tumor events. CONCLUSIONS: Antihuman CD2 monoclonal antibody is a safe immunosuppressive drug which has a favorable impact on early immunological follow-up of liver transplanted patients. The antibody had no impact on late patient and graft survival.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antígenos CD2/imunologia , Imunossupressores/uso terapêutico , Transplante de Fígado/imunologia , Tacrolimo/uso terapêutico , Adulto , Idoso , Relação Dose-Resposta a Droga , Esquema de Medicação , Rejeição de Enxerto/epidemiologia , Sobrevivência de Enxerto , Humanos , Incidência , Infecções/complicações , Falência Hepática/complicações , Falência Hepática/cirurgia , Contagem de Linfócitos , Pessoa de Meia-Idade , Neoplasias/complicações , Período Pós-Operatório , Esteroides/administração & dosagem , Esteroides/uso terapêutico , Análise de Sobrevida
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