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1.
Lancet Psychiatry ; 10(11): 836-847, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37742702

RESUMO

BACKGROUND: Persecutory delusions are a major psychiatric problem that often do not respond sufficiently to standard pharmacological or psychological treatments. We developed a new brief automated virtual reality (VR) cognitive treatment that has the potential to be used easily in clinical services. We aimed to compare VR cognitive therapy with an alternative VR therapy (mental relaxation), with an emphasis on understanding potential mechanisms of action. METHODS: THRIVE was a parallel-group, single-blind, randomised controlled trial across four UK National Health Service trusts in England. Participants were included if they were aged 16 years or older, had a persistent (at least 3 months) persecutory delusion held with at least 50% conviction, reported feeling threatened when outside with other people, and had a primary diagnosis from the referring clinical team of a non-affective psychotic disorder. We randomly assigned (1:1) patients to either THRIVE VR cognitive therapy or VR mental relaxation, using a permuted blocks algorithm with randomly varying block size, stratified by severity of delusion. Usual care continued for all participants. Each VR therapy was provided in four sessions over approximately 4 weeks, supported by an assistant psychologist or clinical psychologist. Trial assessors were masked to group allocation. Outcomes were assessed at 0, 2 (therapy mid-point), 4 (primary endpoint, end of treatment), 8, 16, and 24 weeks. The primary outcome was persecutory delusion conviction, assessed by the Psychotic Symptoms Rating Scale (PSYRATS; rated 0-100%). Outcome analyses were done in the intention-to-treat population. We assessed the treatment credibility and expectancy of the interventions and the two mechanisms (defence behaviours and safety beliefs) that the cognitive intervention was designed to target. This trial is prospectively registered with the ISRCTN registry, ISRCTN12497310. FINDINGS: From Sept 21, 2018, to May 13, 2021 (with a pause due to COVID-19 pandemic restrictions from March 16, 2020, to Sept 14, 2020), we recruited 80 participants with persistent persecutory delusions (49 [61%] men, 31 [39%] women, with a mean age of 40 years [SD 13, range 18-73], 64 [80%] White, six [8%] Black, one [1%] Indian, three [4%] Pakistani, and six [8%] other race or ethnicity). We randomly assigned 39 (49%) participants assigned to VR cognitive therapy and 41 (51%) participants to VR mental relaxation. 33 (85%) participants who were assigned to VR cognitive therapy attended all four sessions, and 35 (85%) participants assigned to VR mental relaxation attended all four sessions. We found no significant differences between the two VR interventions in participant ratings of treatment credibility (adjusted mean difference -1·55 [95% CI -3·68 to 0·58]; p=0·15) and outcome expectancy (-0·91 [-3·42 to 1·61]; p=0·47). 77 (96%) participants provided follow-up data at the primary timepoint. Compared with VR mental relaxation, VR cognitive therapy did not lead to a greater improvement in persecutory delusions (adjusted mean difference -2·16 [-12·77 to 8·44]; p=0·69). Compared with VR mental relaxation, VR cognitive therapy did not lead to a greater reduction in use of defence behaviours (adjusted mean difference -0·71 [-4·21 to 2·79]; p=0·69) or a greater increase in belief in safety (-5·89 [-16·83 to 5·05]; p=0·29). There were 17 serious adverse events unrelated to the trial (ten events in seven participants in the VR cognitive therapy group and seven events in five participants in the VR mental relaxation group). INTERPRETATION: The two VR interventions performed similarly, despite the fact that they had been designed to affect different mechanisms. Both interventions had high uptake rates and were associated with large improvements in persecutory delusions but it cannot be determined that the treatments accounted for the change. Immersive technologies hold promise for the treatment of severe mental health problems. However, their use will likely benefit from experimental research on the application of different therapeutic techniques and the effects on a range of potential mechanisms of action. FUNDING: Medical Research Council Developmental Pathway Funding Scheme and National Institute for Health and Care Research Oxford Health Biomedical Research Centre.

2.
J Infect Dis ; 227(2): 278-287, 2023 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-35867852

RESUMO

BACKGROUND: A novel human parechovirus 3 Australian recombinant (HPeV3-AR) strain emerged in 2013 and coincided with biennial outbreaks of sepsis-like illnesses in infants. We evaluated the molecular evolution of the HPeV3-AR strain and its association with severe HPeV infections. METHODS: HPeV3-positive samples collected from hospitalized infants aged 5-252 days in 2 Australian states (2013-2020) and from a community-based birth cohort (2010-2014) were sequenced. Coding regions were used to conduct phylogenetic and evolutionary analyses. A recombinant-specific polymerase chain reaction was designed and utilized to screen all clinical and community HPeV3-positive samples. RESULTS: Complete coding regions of 54 cases were obtained, which showed the HPeV3-AR strain progressively evolving, particularly in the 3' end of the nonstructural genes. The HPeV3-AR strain was not detected in the community birth cohort until the initial outbreak in late 2013. High-throughput screening showed that most (>75%) hospitalized HPeV3 cases involved the AR strain in the first 3 clinical outbreaks, with declining prevalence in the 2019-2020 season. The AR strain was not statistically associated with increased clinical severity among hospitalized infants. CONCLUSIONS: HPeV3-AR was the dominant strain during the study period. Increased hospital admissions may have been from a temporary fitness advantage and/or increased virulence.


Assuntos
Parechovirus , Infecções por Picornaviridae , Lactente , Humanos , Parechovirus/genética , Filogenia , Austrália/epidemiologia , Recombinação Genética
3.
Phys Eng Sci Med ; 45(4): 1335-1340, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36227496

RESUMO

This work details the clinical pilot study methodology used at Wellington Blood and Cancer Centre (WBCC) before the clinical release of in vivo dosimetry (IVD) system EPIgray™ for head and neck (H&N) volumetric modulated arc therapy (VMAT) treatments. Clinical pilot studies make it possible to select appropriate, department-specific tolerance ranges for the treatment type and site under investigation. An IVD clinical pilot study of H&N VMAT treatments was conducted over 3 months at WBCC using EPIgray™ dose reconstruction software and included 12 patients and 32 individual treatment fractions. Statistical analysis of the dose deviations between the treatment planning system (TPS) dose and EPIgray™ reconstructed dose confirmed that a deviation tolerance range of ± 7.0% was an appropriate choice for H&N VMAT at WBCC.


Assuntos
Dosimetria in Vivo , Neoplasias , Radioterapia de Intensidade Modulada , Humanos , Radioterapia de Intensidade Modulada/métodos , Projetos Piloto , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos
4.
Br J Cardiol ; 29(3): 29, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36873723

RESUMO

This audit compared the management of patients with heart failure with reduced ejection fraction (HFrEF) admitted to a district general hospital (DGH) during comparative eight month periods before and during the COVID-19 pandemic. The periods studied were from 1st February 2019 to 30th September 2019 and between the same dates in 2020. We investigated differences in mortality and patient characteristics (age, gender and new or prior diagnosis). For patients who survived to discharge and who were not referred to palliative care, we also investigated whether there were differences in rates of echocardiography and prescription of angiotensin-converting enzyme (ACE) inhibitors, angiotensin II receptor antagonists and beta blockers. We found that the number of cases was lower during the pandemic and there was a lower mortality rate that was not statistically significant. There was a higher proportion of new cases (odds ratio [OR] 2.21, 95% confidence interval [CI] 1.24 to 3.94, p=0.008) and of female patients (OR 2.03, 95%CI 1.14 to 3.61, p=0.019). For survivors, there was a non-significant decrease in prescription rates for ACE inhibitors and angiotensin II receptor antagonists (81.6% vs. 71.4%, p=0.137) that was not seen for beta blockers. The length of stay was increased and there was also an increase in the interval between admission and echocardiography in patients who were newly diagnosed. Regardless of time period, the time before echocardiography was significantly associated with length of stay.

5.
Home Healthc Now ; 39(6): 302-309, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34738965

RESUMO

Malignant pleural effusion (MPE) resulting from metastatic spread to the pleura frequently occurs in patients with primary lung, breast, hematological, gastrointestinal, and gynecological cancers. These effusions tend to reaccumulate quickly, and the patient requires increasingly frequent thoracentesis. An indwelling pleural catheter allows for dramatic improvement in quality of life as the patient has the power to ease her/his own suffering by draining the effusion at home when shortness of breath and/or chest pain intensifies. Patients with MPE need home healthcare support to address symptom management related to complications of advanced metastatic cancer and antineoplasm treatment regimens. The financial obstacles for the home healthcare agency are explored by using agency supply costs, per visit costs, and the patient-driven groupings reimbursement mode grouper to estimate reimbursement. Care for a home healthcare patient with MPE costs Medicare approximately $64.50 per day, markedly less than costs for hospitalization and outpatient thoracentesis. Unfortunately, agencies must absorb the cost of vacuum drainage bottles. Whereas a small positive balance of $291 was estimated for the first 30-day posthospital episode, losses were estimated at $1,185 to $1,633 for subsequent 30-day episodes. Absorbing these costs has become extremely difficult as home healthcare agencies are experiencing unprecedented COVID-19 infection control and staffing-related costs.


Assuntos
COVID-19 , Derrame Pleural Maligno , Idoso , Cateteres de Demora/efeitos adversos , Drenagem , Feminino , Humanos , Medicare , Derrame Pleural Maligno/terapia , Pleurodese , Qualidade de Vida , SARS-CoV-2 , Estados Unidos
6.
Issues Ment Health Nurs ; 41(5): 404-414, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32202946

RESUMO

Little is known about the perceptions of sibling relationships from the direct perspective of service users with mental health difficulties; this study aimed to address this gap. Semi-structured interviews were carried out with adult male inpatients who had severe and enduring mental health difficulties. Interpretative phenomenological analysis was used to analyse the data and revealed three main themes: (1) The closeness of the sibling bond; (2) The change in sibling dynamics following diagnosis and admission; (3) Siblings' contribution to mental health and recovery. The implications of involving siblings in care and the benefits of service user led research are discussed.


Assuntos
Transtornos Mentais/psicologia , Serviços de Saúde Mental , Relações entre Irmãos , Irmãos/psicologia , Adolescente , Adulto , Feminino , Humanos , Pacientes Internados/psicologia , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , Reino Unido , Adulto Jovem
7.
Clin Infect Dis ; 71(1): 116-127, 2020 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-31406985

RESUMO

BACKGROUND: Hospital-based studies identify parechovirus (PeV), primarily PeV-A3, as an important cause of severe infections in young children. However, few community-based studies have been published and the true PeV infection burden is unknown. We investigated PeV epidemiology in healthy children participating in a community-based, longitudinal birth cohort study. METHODS: Australian children (n = 158) enrolled in the Observational Research in Childhood Infectious Diseases (ORChID) study were followed from birth until their second birthday. Weekly stool and nasal swabs and daily symptom diaries were collected. Swabs were tested for PeV by reverse-transcription polymerase chain reaction and genotypes determined by subgenomic sequencing. Incidence rate, infection characteristics, clinical associations, and virus codetections were investigated. RESULTS: PeV was detected in 1423 of 11 124 (12.8%) and 17 of 8100 (0.2%) stool and nasal swabs, respectively. Major genotypes among the 306 infection episodes identified were PeV-A1 (47.9%), PeV-A6 (20.1%), and PeV-A3 (18.3%). The incidence rate was 144 episodes (95% confidence interval, 128-160) per 100 child-years. First infections appeared at a median age of 8 (interquartile range, 6.0-11.7) months. Annual seasonal peaks changing from PeV-A1 to PeV-A3 were observed. Infection was positively associated with age ≥6 months, summer season, nonexclusive breastfeeding at age <3 months, and formal childcare attendance before age 12 months. Sole PeV infections were either asymptomatic (38.4%) or mild (32.7%), while codetection with other viruses in stool swabs was common (64.4%). CONCLUSIONS: In contrast with hospital-based studies, this study showed that diverse and dynamically changing PeV genotypes circulate in the community causing mild or subclinical infections in children.Parechovirus can cause severe illnesses in children. However, studies focus mainly on hospitalized populations. True disease burden in the community remains largely unknown. From our community-based cohort, we found diverse parechovirus genotypes in the community, causing mild or subclinical infections in children. CLINICAL TRIALS REGISTRATION: NCT01304914.


Assuntos
Parechovirus , Infecções por Picornaviridae , Austrália/epidemiologia , Criança , Pré-Escolar , Estudos de Coortes , Genótipo , Humanos , Lactente , Parechovirus/genética , Infecções por Picornaviridae/epidemiologia
8.
JOR Spine ; 2(1): e1049, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31463463

RESUMO

The intervertebral disc (IVD) is a highly hydrated tissue, the rich proteoglycan matrix imbibes water, enabling the disc to withstand compressive loads. During aging and degeneration increased matrix degradation leads to dehydration and loss of function. Aquaporins (AQP) are a family of transmembrane channel proteins that selectively allow the passage of water in and out of cells and are responsible for maintaining water homeostasis in many tissues. Here, the expression of all 13 AQPs at gene and protein level was investigated in human and canine nondegenerate and degenerate IVDs to develop an understanding of the role of AQPs during degeneration. Furthermore, in order to explore the transition of notochordal cells (NCs) towards nucleus pulposus (NP) cells, AQP expression was investigated in canine IVDs enriched in NCs to understand the role of AQPs in IVD maturation. AQP0, 1, 2, 3, 4, 5, 6, 7, and 9 were expressed at gene and protein level in both nondegenerate and degenerate human NP tissue. AQP2 and 7 immunopositivity increased with degeneration in human NP tissue, whereas AQP4 expression decreased with degeneration in a similar way to AQP1 and 5 shown previously. All AQP proteins that were identified in human NP tissue were also expressed in canine NP tissue. AQP2, 5, 6, and 9 were found to localize to vacuole-like membranes and cell membranes in NC cells. In conclusion, AQPs were abundantly expressed in human and canine IVDs. The expression of many AQP isotypes potentially alludes to multifaceted functions related to adaption of NP cells to the conditions they encounter within their microenvironment in health and degeneration. The presence of AQPs within the IVD may suggest an adaptive role for these water channels during the development and maintenance of the healthy, mature IVD.

9.
Methods Mol Biol ; 1618: 191-201, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28523509

RESUMO

Mass Spectrometry Imaging (MSI) has evolved into a valuable tool for research into and the diagnosis of disease pathology. The ability to perform multiplex analysis of a wide range of molecules (e.g., proteins, lipids, and metabolites) simultaneously per tissue section while retaining the histological structure of the sample allows molecular information and tissue morphology to be correlated, thus increasing our understanding of a particular disease. Further development of MSI is required to improve suitability to the alternative models available, so that the combined approach can successfully provide the information required in disease characterization and prevention. MSI has been shown to be capable of providing spatiomolecular information in tumor spheroids, living skin equivalents, and ex vivo human tissues. Due to a considerable interest and scientific effort there are many more designed alternative disease models available which would benefit from the information MSI could provide.


Assuntos
Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Humanos , Espectrometria de Massas/métodos , Proteínas/química , Esferoides Celulares/metabolismo
10.
J Health Organ Manag ; 30(8): 1301-1307, 2016 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-27834600

RESUMO

Purpose Worldwide, there is significant growth in the cost of (and demand for) healthcare, which often clashes with a requirement to contain expenditure. This duality leads to an increasing need for a systematic approach to disinvestment in health technologies. The purpose of this paper is to consider the challenges and opportunities for disinvestment policy decisions in Australia. It discusses the implementation of the Choosing Wisely campaign and the need for rigorous evaluation of such campaigns in the Australian healthcare system. Design/methodology/approach The authors highlight characteristics of disinvestment: what it is and what it is not and discuss international examples of identifying low value care, including the recent Choosing Wisely initiative. The authors discuss the barriers to implementing initiatives such as Choosing Wisely and the complexities in evaluating their effectiveness. Findings While the primary purpose of the Choosing Wisely campaign is improved decision making through clinical engagement, it is expected that implementation could lead to resource savings alongside improvements in patient safety and service quality. While there is research looking to understand the barriers and facilitators to the implementation of initiatives such as Choosing Wisely, little is known about broader patient impacts, and more attention on the quantification of their effect on both patient outcomes and resource use is needed. Originality/value This work highlights the limited knowledge around implementation of disinvestment strategies and the paucity of research around the impact of strategies such as Choosing Wisely in the Australian public hospital system. This is important as future research in this area will give greater certainty about the benefits and consequences of Choosing Wisely leading to improved opportunities for resource savings and patient safety and quality.


Assuntos
Financiamento Governamental , Política de Saúde , Formulação de Políticas , Austrália , Tecnologia Biomédica/economia , Tomada de Decisões , Saúde Pública
11.
Proteomics ; 16(11-12): 1718-25, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27226230

RESUMO

MALDI-MS Imaging is a novel label-free technique that can be used to visualize the changes in multiple mass responses following treatment. Following treatment with proinflammatory cytokine interleukin-22 (IL-22), the epidermal differentiation of Labskin, a living skin equivalent (LSE), successfully modeled psoriasis in vitro. Masson's trichrome staining enabled visualization and quantification of epidermal differentiation between the untreated and IL-22 treated psoriatic LSEs. Matrix-assisted laser desorption ionization mass spectrometry imaging was used to observe the spatial location of the psoriatic therapy drug acetretin following 48 h treatments within both psoriatic and normal LSEs. After 24 h, the drug was primarily located in the epidermal regions of both the psoriatic and nonpsoriatic LSE models whereas after 48 h it was detectible in the dermis.


Assuntos
Epiderme/ultraestrutura , Psoríase/genética , Pele/efeitos dos fármacos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Animais , Diferenciação Celular/efeitos dos fármacos , Modelos Animais de Doenças , Epiderme/efeitos dos fármacos , Humanos , Imageamento Tridimensional/métodos , Interleucinas/administração & dosagem , Camundongos , Psoríase/patologia , Pele/metabolismo , Pele/fisiopatologia , Engenharia Tecidual/métodos , Interleucina 22
12.
Biochim Biophys Acta ; 1850(12): 2410-21, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26365508

RESUMO

BACKGROUND: Aquaporin (AQP) water channels are best known as passive transporters of water that are vital for water homeostasis. SCOPE OF REVIEW: AQP knockout studies in whole animals and cultured cells, along with naturally occurring human mutations suggest that the transport of neutral solutes through AQPs has important physiological roles. Emerging biophysical evidence suggests that AQPs may also facilitate gas (CO2) and cation transport. AQPs may be involved in cell signalling for volume regulation and controlling the subcellular localization of other proteins by forming macromolecular complexes. This review examines the evidence for these diverse functions of AQPs as well their physiological relevance. MAJOR CONCLUSIONS: As well as being crucial for water homeostasis, AQPs are involved in physiologically important transport of molecules other than water, regulation of surface expression of other membrane proteins, cell adhesion, and signalling in cell volume regulation. GENERAL SIGNIFICANCE: Elucidating the full range of functional roles of AQPs beyond the passive conduction of water will improve our understanding of mammalian physiology in health and disease. The functional variety of AQPs makes them an exciting drug target and could provide routes to a range of novel therapies.


Assuntos
Aquaporinas/fisiologia , Homeostase , Água/metabolismo , Sequência de Aminoácidos , Animais , Aquaporinas/química , Mamíferos , Dados de Sequência Molecular
13.
Fly (Austin) ; 9(1): 7-15, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26267354

RESUMO

General anesthetics achieve behavioral unresponsiveness via a mechanism that is incompletely understood. The study of genetic model systems such as the fruit fly Drosophila melanogaster is crucial to advancing our understanding of how anesthetic drugs render animals unresponsive. Previous studies have shown that wild-type control strains differ significantly in their sensitivity to general anesthetics, which potentially introduces confounding factors for comparing genetic mutations placed on these wild-type backgrounds. Here, we examined a variety of behavioral and electrophysiological endpoints in Drosophila, in both adult and larval animals. We characterized these endpoints in 3 commonly used fly strains: wild-type Canton Special (CS), and 2 commonly used white-eyed strains, isoCJ1 and w(1118). We found that CS and isoCJ1 show remarkably similar sensitivity to isoflurane across a variety of behavioral and electrophysiological endpoints. In contrast, w(1118) is resistant to isoflurane compared to the other 2 strains at both the adult and larval stages. This resistance is however not reflected at the level of neurotransmitter release at the larval neuromuscular junction (NMJ). This suggests that the w(1118) strain harbors another mutation that produces isoflurane resistance, by acting on an arousal pathway that is most likely preserved between larval and adult brains. This mutation probably also affects sleep, as marked differences between isoCJ1 and w(1118) have also recently been found for behavioral responsiveness and sleep intensity measures.


Assuntos
Anestésicos Inalatórios/farmacologia , Drosophila melanogaster/efeitos dos fármacos , Isoflurano/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Feminino , Junção Neuromuscular/efeitos dos fármacos , Especificidade da Espécie
14.
Int J Palliat Nurs ; 21(8): 372-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26312532

RESUMO

BACKGROUND: Ascites is an accumulation of serous fluid in the abdominal cavity. It can be caused by both malignant and non-malignant conditions and produces distressing symptoms. There have been no qualitative studies looking at the experiences of patients with non-malignant ascites. AIMS: To explore the experiences of patients living with non-malignant ascites and its management. Also, to explore the views of these patients about services available to them. METHOD: Phenomenological qualitative research study using digitally recorded semi-structured interviews. SETTING AND PARTICIPANTS: Six adult patients with non-malignant ascites who were receiving paracentesis to manage their symptoms in an acute hospital day unit. RESULTS: Participants experienced a wide variety of physical symptoms. They discussed how the ascites impacted on their social lives. They had views on diuretics, low sodium diet and paracentesis as methods of symptom management. Participants' confidence in staff performing paracentesis was a common finding, particularly as ultrasound was rarely used. While only some were suitable for liver transplant, all discussed their future care needs. CONCLUSION: Participants' experiences of non-malignant ascites are that it has a considerable effect on their quality of life. Patients like the system of day case admission for drainage, but question whether this is sustainable. Advanced practitioners can successfully provide a paracentesis service for these patients in hospitals and potentially this is transferable to hospices. Patients seemed happy to consider the option of semi-permanent drains and pumps as methods of managing ascites.


Assuntos
Ascite/psicologia , Ascite/terapia , Drenagem/métodos , Hepatopatias/complicações , Cuidados Paliativos/métodos , Paracentese/enfermagem , Qualidade de Vida/psicologia , Adulto , Ascite/etiologia , Gerenciamento Clínico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Pesquisa Qualitativa
15.
J Biol Chem ; 290(27): 16873-81, 2015 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-26013827

RESUMO

The aquaporin family of integral membrane proteins is composed of channels that mediate cellular water flow. Aquaporin 4 (AQP4) is highly expressed in the glial cells of the central nervous system and facilitates the osmotically driven pathological brain swelling associated with stroke and traumatic brain injury. Here we show that AQP4 cell surface expression can be rapidly and reversibly regulated in response to changes of tonicity in primary cortical rat astrocytes and in transfected HEK293 cells. The translocation mechanism involves PKA activation, influx of extracellular calcium, and activation of calmodulin. We identify five putative PKA phosphorylation sites and use site-directed mutagenesis to show that only phosphorylation at one of these sites, serine 276, is necessary for the translocation response. We discuss our findings in the context of the identification of new therapeutic approaches to treating brain edema.


Assuntos
Aquaporina 4/metabolismo , Edema Encefálico/metabolismo , Motivos de Aminoácidos , Animais , Aquaporina 4/química , Aquaporina 4/genética , Astrócitos/metabolismo , Edema Encefálico/genética , Cálcio/metabolismo , Calmodulina/metabolismo , Células Cultivadas , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Células HEK293 , Humanos , Pressão Osmótica , Fosforilação , Transporte Proteico , Ratos
16.
Oncotarget ; 6(14): 11945-58, 2015 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-25844601

RESUMO

Objectives of this study were to investigate whether AQP1 and AQP5 expression is altered during intervertebral disc degeneration and if hypoxia and HIF-1 regulate their expression in NP cells. AQP expression was measured in human tissues from different degenerative grades; regulation by hypoxia and HIF-1 was studied using promoter analysis and gain- and loss-of-function experiments. We show that both AQPs are expressed in the disc and that mRNA and protein levels decline with human disease severity. Bioinformatic analyses of AQP promoters showed multiple evolutionarily conserved HREs. Surprisingly, hypoxia failed to induce promoter activity or expression of either AQP. While genomic chromatin immunoprecipitation showed limited binding of HIF-1α to conserved HREs, their mutation did not suppress promoter activities. Stable HIF-1α suppression significantly decreased mRNA and protein levels of both AQPs, but HIF-1α failed to induce AQP levels following accumulation. Together, our results demonstrate that AQP1 and AQP5 expression is sensitive to human disc degeneration and that HIF-1α uniquely maintains basal expression of both AQPs in NP cells, independent of oxemic tension and HIF-1 binding to promoter HREs. Diminished HIF-1 activity during degeneration may suppress AQP levels in NP cells, compromising their ability to respond to extracellular osmolarity changes.


Assuntos
Aquaporina 1/biossíntese , Aquaporina 5/biossíntese , Regulação da Expressão Gênica/fisiologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Degeneração do Disco Intervertebral/metabolismo , Animais , Western Blotting , Hipóxia Celular/fisiologia , Imunoprecipitação da Cromatina , Humanos , Imuno-Histoquímica , Microscopia de Fluorescência , Ratos , Reação em Cadeia da Polimerase em Tempo Real , Elementos de Resposta/fisiologia , Transfecção
17.
Med Phys ; 42(4): 1625-39, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25832053

RESUMO

PURPOSE: To develop a method to verify the dose delivery in relation to the individual control points of intensity modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT) using an ionization chamber. In addition to more effective problem solving during patient-specific quality assurance (QA), the aim is to eventually map out the limitations in the treatment chain and enable a targeted improvement of the treatment technique in an efficient way. METHODS: Pretreatment verification was carried out for 255 treatment plans that included a broad range of treatment indications in two departments using the equipment of different vendors. In-house developed software was used to enable calculation of the dose delivery for the individual beamlets in the treatment planning system (TPS), for data acquisition, and for analysis of the data. The observed deviations were related to various delivery and measurement parameters such as gantry angle, field size, and the position of the detector with respect to the field edge to distinguish between error sources. RESULTS: The average deviation of the integral fraction dose during pretreatment verification of the planning target volume dose was -2.1% ± 2.2% (1 SD), -1.7% ± 1.7% (1 SD), and 0.0% ± 1.3% (1 SD) for IMRT at the Radboud University Medical Center (RUMC), VMAT (RUMC), and VMAT at the Wellington Blood and Cancer Centre, respectively. Verification of the dose to organs at risk gave very similar results but was generally subject to a larger measurement uncertainty due to the position of the detector at a high dose gradient. The observed deviations could be related to limitations of the TPS beam models, attenuation of the treatment couch, as well as measurement errors. The apparent systematic error of about -2% in the average deviation of the integral fraction dose in the RUMC results could be explained by the limitations of the TPS beam model in the calculation of the beam penumbra. CONCLUSIONS: This study showed that time-resolved dosimetry using an ionization chamber is feasible and can be largely automated which limits the required additional time compared to integrated dose measurements. It provides a unique QA method which enables identification and quantification of the contribution of various error sources during IMRT and VMAT delivery.


Assuntos
Radiometria/instrumentação , Radiometria/métodos , Radioterapia de Intensidade Modulada/métodos , Estudos de Viabilidade , Humanos , Neoplasias/radioterapia , Aceleradores de Partículas , Reconhecimento Automatizado de Padrão/métodos , Imagens de Fantasmas , Fótons/uso terapêutico , Poliestirenos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/instrumentação , Software , Fatores de Tempo
18.
Anesthesiology ; 122(5): 1060-74, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25738637

RESUMO

BACKGROUND: Recent evidence suggests that general anesthetics activate endogenous sleep pathways, yet this mechanism cannot explain the entirety of general anesthesia. General anesthetics could disrupt synaptic release processes, as previous work in Caenorhabditis elegans and in vitro cell preparations suggested a role for the soluble NSF attachment protein receptor protein, syntaxin1A, in mediating resistance to several general anesthetics. The authors questioned whether the syntaxin1A-mediated effects found in these reductionist systems reflected a common anesthetic mechanism distinct from sleep-related processes. METHODS: Using the fruit fly model, Drosophila melanogaster, the authors investigated the relevance of syntaxin1A manipulations to general anesthesia. The authors used different behavioral and electrophysiological endpoints to test the effect of syntaxin1A mutations on sensitivity to isoflurane. RESULTS: The authors found two syntaxin1A mutations that confer opposite general anesthesia phenotypes: syxH3-C, a 14-amino acid deletion mutant, is resistant to isoflurane (n = 40 flies), and syxKARRAA, a strain with two amino acid substitutions, is hypersensitive to the drug (n = 40 flies). Crucially, these opposing effects are maintained across different behavioral endpoints and life stages. The authors determined the isoflurane sensitivity of syxH3-C at the larval neuromuscular junction to assess effects on synaptic release. The authors find that although isoflurane slightly attenuates synaptic release in wild-type animals (n = 8), syxH3-C preserves synaptic release in the presence of isoflurane (n = 8). CONCLUSION: The study results are evidence that volatile general anesthetics target synaptic release mechanisms; in addition to first activating sleep pathways, a major consequence of these drugs may be to decrease the efficacy of neurotransmission.


Assuntos
Anestésicos Inalatórios/farmacologia , Proteínas de Drosophila/fisiologia , Resistência a Medicamentos/genética , Hipersensibilidade/genética , Isoflurano/farmacologia , Proteínas Qa-SNARE/fisiologia , Animais , Comportamento Animal/efeitos dos fármacos , Proteínas de Drosophila/genética , Drosophila melanogaster , Larva , Locomoção/efeitos dos fármacos , Mutação , Junção Neuromuscular/efeitos dos fármacos , Neurotransmissores/metabolismo , Proteínas Qa-SNARE/genética , Reflexo de Sobressalto , Sono/efeitos dos fármacos
19.
Biochim Biophys Acta ; 1840(5): 1492-506, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24090884

RESUMO

BACKGROUND: Emerging evidence supports the view that (AQP) aquaporin water channels are regulators of transcellular water flow. Consistent with their expression in most tissues, AQPs are associated with diverse physiological and pathophysiological processes. SCOPE OF REVIEW: AQP knockout studies suggest that the regulatory role of AQPs, rather than their action as passive channels, is their critical function. Transport through all AQPs occurs by a common passive mechanism, but their regulation and cellular distribution varies significantly depending on cell and tissue type; the role of AQPs in cell volume regulation (CVR) is particularly notable. This review examines the regulatory role of AQPs in transcellular water flow, especially in CVR. We focus on key systems of the human body, encompassing processes as diverse as urine concentration in the kidney to clearance of brain oedema. MAJOR CONCLUSIONS: AQPs are crucial for the regulation of water homeostasis, providing selective pores for the rapid movement of water across diverse cell membranes and playing regulatory roles in CVR. Gating mechanisms have been proposed for human AQPs, but have only been reported for plant and microbial AQPs. Consequently, it is likely that the distribution and abundance of AQPs in a particular membrane is the determinant of membrane water permeability and a regulator of transcellular water flow. GENERAL SIGNIFICANCE: Elucidating the mechanisms that regulate transcellular water flow will improve our understanding of the human body in health and disease. The central role of specific AQPs in regulating water homeostasis will provide routes to a range of novel therapies. This article is part of a Special Issue entitled Aquaporins.


Assuntos
Aquaporinas/fisiologia , Água Corporal/metabolismo , Transporte Biológico , Tamanho Celular , Humanos
20.
Int J Palliat Nurs ; 19(4): 171-6, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23967771

RESUMO

AIM: To explore patients' views on living with anaemia and undergoing blood transfusions in a day hospice. METHODS: This was a qualitative study using semi-structured interviews. Ten patients who between them had received 90 transfusions were purposively sampled from the hospice day unit. The interviews were digitially recorded, transcribed anonymously, and the transcripts analysed using a phenomenological analysis framework. FINDINGS: Tiredness was the most common symptom of anaemia. Participants liked attending the day hospice instead of hospital for their transfusions owing to differences in transport, parking, waiting time, and space to ask questions. The majority had no concerns about hospice transfusion and would be happy to return for further treatment. CONCLUSIONS: Haematology patients can have a good experience when undergoing blood transfusion at a day hospice. Hospices should perhaps offer this procedure more widely.


Assuntos
Instituições de Assistência Ambulatorial , Transfusão de Sangue/psicologia , Hospitais para Doentes Terminais , Pacientes Ambulatoriais/psicologia , Inglaterra , Ética , Humanos , Qualidade de Vida
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