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1.
Paediatr Anaesth ; 33(11): 938-945, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37555370

RESUMO

BACKGROUND: Liver transplantation is the life-saving treatment for many end-stage pediatric liver diseases. The perioperative course, including surgical and anesthetic factors, have an important influence on the trajectory of this high-risk population. Given the complexity and variability of the immediate postoperative course, there would be utility in identifying risk factors that allow prediction of adverse outcomes and intensive care unit trajectories. AIMS: The aim of this study was to develop and validate a risk prediction model of prolonged intensive care unit length of stay in the pediatric liver transplant population. METHODS: This is a retrospective analysis of consecutive pediatric isolated liver transplant recipients at a single institution between April 1, 2013 and April 30, 2020. All patients under the age of 18 years receiving a liver transplant were included in the study (n = 186). The primary outcome was intensive care unit length of stay greater than 7 days. RESULTS: Recipient and donor characteristics were used to develop a multivariable logistic regression model. A total of 186 patients were included in the study. Using multivariable logistic regression, we found that age < 12 months (odds ratio 4.02, 95% confidence interval 1.20-13.51, p = .024), metabolic or cholestatic disease (odds ratio 2.66, 95% confidence interval 1.01-7.07, p = .049), 30-day pretransplant hospital admission (odds ratio 8.59, 95% confidence interval 2.27-32.54, p = .002), intraoperative red blood cells transfusion >40 mL/kg (odds ratio 3.32, 95% confidence interval 1.12-9.81, p = .030), posttransplant return to the operating room (odds ratio 11.45, 95% confidence interval 3.04-43.16, p = .004), and major postoperative respiratory event (odds ratio 32.14, 95% confidence interval 3.00-343.90, p < .001) were associated with prolonged intensive care unit length of stay. The model demonstrates a good discriminative ability with an area under the receiver operative curve of 0.888 (95% confidence interval, 0.824-0.951). CONCLUSIONS: We develop and validate a model to predict prolonged intensive care unit length of stay in pediatric liver transplant patients using risk factors from all phases of the perioperative period.


Assuntos
Transplante de Fígado , Humanos , Criança , Adolescente , Lactente , Estudos Retrospectivos , Tempo de Internação , Unidades de Terapia Intensiva , Fatores de Risco
2.
Can J Anaesth ; 68(5): 693-705, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33512661

RESUMO

PURPOSE: Anesthesia information management systems (AIMS) are gradually replacing paper documentation of anesthesia care. This study sought to determine the current status of AIMS adoption and the level of health informatics expertise in Canadian academic anesthesia departments. METHODS: Department heads or their designates of Canadian academic anesthesia departments were invited by e-mail to complete an online survey between September 2019 and February 2020. The survey elicited information on current AIMS or future plans for an AIMS installation, the number of department members dedicated to clinical informatics issues, the gross level of health informatics expertise at each department, perceived advantages of AIMS, and perceived disadvantages of and barriers to implementation of AIMS. RESULTS: Of the 64 departments invited to participate, 63 (98.4%) completed the survey. Only 21 (33.3%) of the departments had AIMS. Of the 42 departments still charting on paper, 23 (54.8%) reported planning to install an AIMS within the next five years. Forty-six departments (73%) had at least one anesthesiologist tasked with dealing with AIMS or electronic health record issues. Most reported having no department members with extensive knowledge or formal training in health informatics. The top three perceived barriers and disadvantages to an AIMS installation were its initial cost, lack of funding, and a lack of technical support dedicated specifically to AIMS. The top three advantages departments wished to prioritize with AIMS were accurate clinical documentation, better data for quality improvement initiatives, and better data for research. CONCLUSIONS: A majority of Canadian academic anesthesia departments are still using paper records, but this trend is expected to reverse in the next five years as more departments install an AIMS. Health informatics expertise is lacking in most of the departments, with a minority planning to support the training of future anesthesia informaticians.


RéSUMé: OBJECTIF : Les systèmes de gestion de l'information en anesthésie (SGIA) remplacent progressivement la documentation sur papier des soins anesthésiques. Cette étude a tenté de déterminer l'état actuel de l'adoption des SGIA et le niveau d'expertise en informatique de la santé dans les départements universitaires d'anesthésie canadiens. MéTHODE : Les chefs de département ou des responsables désignés des départements universitaires d'anesthésie canadiens ont été invités par courriel à remplir un sondage électronique entre les mois de septembre 2019 et février 2020. L'enquête a permis d'obtenir de l'information sur les SGIA actuels ou les plans futurs d'implantation d'un SGIA, le nombre de membres du département en charge des questions d'informatique clinique, le niveau brut d'expertise en informatique de la santé dans chaque département, les avantages perçus des SGIA, et les inconvénients perçus ainsi que les obstacles à la mise en œuvre des SGIA. RéSULTATS : Sur les 64 départements invités à participer, 63 (98,4 %) ont rempli le sondage. Seuls 21 (33,3 %) départements disposaient d'un SGIA. Sur les 42 départements utilisant encore des dossiers papier, 23 (54,8 %) ont déclaré avoir l'intention d'installer un SGIA au cours des cinq prochaines années. Quarante-six départements (73 %) comptaient au moins un anesthésiologiste chargé de gérer les problèmes liés au SGIA ou aux dossiers médicaux électroniques. La plupart des départements ont déclaré ne pas compter, parmi leurs membres, de personne possédant des connaissances approfondies ou une formation officielle en informatique de la santé. Les trois principaux obstacles et inconvénients perçus à la mise en oeuvre d'un SGIA étaient son coût initial, le manque de financement et un manque de soutien technique dédié spécifiquement aux SGIA. Les trois principaux avantages que les départements souhaitaient prioriser avec un SGIA étaient une documentation clinique exacte, de meilleures données pour les initiatives d'amélioration de la qualité et de meilleures données pour la recherche. CONCLUSION : La majorité des départements universitaires d'anesthésie canadiens utilisent toujours des dossiers papier, mais cette tendance devrait s'inverser au cours des cinq prochaines années, au fur et à mesure qu'un plus grand nombre de départements installeront des SGIA. L'expertise en informatique de la santé fait défaut dans la plupart des départements, et une minorité des départements a l'intention de soutenir la formation des futurs informaticiens en anesthésie.


Assuntos
Anestesia , Anestesiologia , Serviço Hospitalar de Anestesia , Canadá , Humanos , Gestão da Informação
3.
Public Health ; 180: 109-113, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31881464

RESUMO

OBJECTIVES: The political controversy surrounding firearm fatalities in US youths (aged 15-24 years) continues. This study examines whether a public health approach could reduce gun-related deaths in the US. METHODS: Based on the latest World Health Organization (WHO) data, current (2015) numbers and rates per million of US civilian violent deaths (CVDs) (including transport deaths, suicides and homicides) for both the general population and youths (aged 15-24 years) are examined. US CVD results are considered in a wider context by comparing the results with those of seven other major Western countries (MWCs). To demonstrate the effectiveness of a public health policy, transport deaths between 1979 and 2015 are analysed, which corresponds to a time period when government interventions based on technical improvements and behaviour change were implemented to improve road safety. The statistical significance of the comparison between road fatalities and suicide rates between 1979 and 2015 is determined by the chi-squared test. RESULTS: In 2015, the total number of US CVDs was 101,456, consisting of 44,193 suicides and 17,588 homicides (of which 30,891 were likely to be gun-related deaths). Youth deaths totalled 17,432; 5491 suicides and 4732 homicides, including approximately 5112 gun-related deaths. US CVDs are substantially higher than the other MWCs for both the general population and youths. In 1979, US transport deaths were 57,577, which decreased to 39,675 in 2015. Every country's public health approach to reduce road deaths, when compared with suicides, was highly statistically significant. CONCLUSIONS: Government interventions have reduced transport deaths; thus, new policies may also reduce gun-related violence. The evidence points towards a public health approach, such as that used to reduce road deaths, which could help reduce US firearm-related deaths to levels comparable with other MWCs.


Assuntos
Causas de Morte , Violência com Arma de Fogo/prevenção & controle , Violência com Arma de Fogo/estatística & dados numéricos , Internacionalidade , Adolescente , Governo , Homicídio/estatística & dados numéricos , Humanos , Prática de Saúde Pública , Política Pública , Suicídio/estatística & dados numéricos , Estados Unidos/epidemiologia , Adulto Jovem
4.
J Toxicol Environ Health A ; 82(4): 279-298, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30890031

RESUMO

Lead (Pb) is a persistent environmental pollutant that has a structure and charge similar to many ions, such as calcium, that are essential for normal cellular function. Pb may compete with calcium for protein binding sites and inhibit signaling pathways within the cell affecting many organ systems including the immune system. The aim of the current study was to assess whether the calcium/calmodulin pathway is a principal target of environmentally relevant Pb during pro-inflammatory activation in a RAW 264.7 macrophage cell line. RAW 264.7 cells were cultured with 5 µM Pb(NO3)2, LPS, rIFNγ, or LPS+rIFNγ for 12, 24, or 48 hr. Intracellular protein signaling and multiple functional endpoints were investigated to determine Pb-mediated effects on macrophage function. Western blot analysis revealed that Pb initially modulated nuclear localization of NFκB p65 and cytoplasmic phosphorylation of CaMKIV accompanied by increased phosphorylation of STAT1ß at 24 hr. Macrophage proliferation was significantly decreased at 12 hr in the presence of Pb, while nitric oxide (NO) was significantly reduced at 12 and 24 hr. Cells cultured with Pb for 12, 24, or 48 hr exhibited altered cytokine levels after specific stimuli activation. Our findings are in agreement with previous reports suggesting that macrophage pro-inflammatory responses are significantly modulated by Pb. Further, Pb-induced phosphorylation of CaMKIV (pCaMKIV), observed in the present study, may be a contributing factor in metal-induced autophagy noted in our previous study with this same cell line.


Assuntos
Inflamação/fisiopatologia , Fator Regulador 1 de Interferon/efeitos dos fármacos , Chumbo/toxicidade , Células RAW 264.7/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/efeitos dos fármacos , Animais , Fator Regulador 1 de Interferon/metabolismo , Camundongos , Células RAW 264.7/metabolismo , Receptor 4 Toll-Like/metabolismo
5.
J Clin Pharm Ther ; 43(3): 353-358, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29356021

RESUMO

WHAT IS KNOWN AND OBJECTIVE: Fidaxomicin was recently approved for the treatment of Clostridium difficile infection (CDI). Limited data on its use exist outside of the phase 3 trials. The purposes of this study were to assess the compliance with the Veterans Health Administration (VHA) fidaxomicin criteria for use and describe patient characteristics and outcomes following fidaxomicin treatment for CDI using real-world data within the VHA system. METHODS: This was a multicentre, retrospective, observational study including all adult patients who received at least 1 dose of fidaxomicin at any Veterans Affairs Medical Center. RESULTS AND DISCUSSION: A total of 880 unique patients received 1098 courses of fidaxomicin, resulting in an overall usage rate per C. difficile-positive laboratory test of 1.98%. The rate of fidaxomicin courses per 1000 C. difficile-positive diagnostic tests increased steadily from 2011 through 2015 and plateaued from 2015 to 2016. Compliance with the VHA criteria for use was low (9.1%). The majority of courses were given for a first recurrence (25.0%), followed by an initial episode (23.9%) of CDI. The failure and recurrence rates were 6.8% and 24.4%, respectively. WHAT IS NEW AND CONCLUSION: Although overall use of fidaxomicin was low, compliance with the VHA criteria for use was also low, suggesting that the criteria may need to be revised. Further studies are warranted to clarify the role of fidaxomicin in clinical practice.


Assuntos
Aminoglicosídeos/administração & dosagem , Antibacterianos/administração & dosagem , Infecções por Clostridium/tratamento farmacológico , Padrões de Prática Médica/estatística & dados numéricos , Adulto , Infecções por Clostridium/diagnóstico , Fidaxomicina , Fidelidade a Diretrizes , Humanos , Guias de Prática Clínica como Assunto , Recidiva , Estudos Retrospectivos , Estados Unidos , United States Department of Veterans Affairs
6.
Soft Matter ; 13(40): 7341-7351, 2017 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-28990627

RESUMO

Vesicles are a highly attractive morphology to achieve in micellar dispersions of block copolymers (BCP) in epoxy thermosets due to the fact that small amounts can affect a large volume fraction of the matrix, a fact that is important for toughening purposes. However, generating vesicles in epoxy matrices requires operating in a narrow range of formulations and processing conditions. In this report, we show that block-copolymer vesicles dispersed in an epoxy matrix could be obtained through a sphere-to-cylinder-to-vesicle micellar transition induced by visible-light photopolymerization at room temperature. A 10 wt% colloidal solution of poly(ethylene-co-butene)-block-poly(ethylene oxide) (PEB-b-PEO) block copolymer (BCP) in an epoxy monomer (DGEBA) self-assembled into spherical micelles as shown by small-angle X-ray scattering (SAXS). During a slow photopolymerization of the epoxy monomer carried out at room temperature, a sphere-to-cylinder-to-vesicle transition took place as revealed by in situ SAXS and TEM images. This was driven by the tendency of the system to reduce the local interfacial curvature as a response to a decrease in the miscibility of PEO blocks in the polymerizing epoxy matrix. When the BCP concentration was increased from 10 to 20 and 40 wt%, the final structure evolved from bilayer vesicles to multilayer vesicles and to lamellae, respectively. In particular, for 20 wt% PEB-b-PEO, transient structures such as partially fused multilayered vesicles were observed by TEM, giving insight into the growth mechanism of multilayer vesicles. On the contrary, when a relatively fast thermal polymerization was performed at 80 °C, the final morphology consisted of kinetically trapped spherical and cylindrical micelles. Hopefully, this study will lead to new protocols for the preparation of vesicles dispersed in epoxy matrices in a controlled way.

8.
Neurochem Res ; 41(3): 589-92, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26303506

RESUMO

Astrocytes execute essential functions in the healthy CNS, whilst also being implicated as a limitation to functional regeneration and repair after injury. They respond to injury to minimize damage to healthy tissue whilst also attempting to seal the broken blood-brain-barrier, however, they impede recovery if they are persistent and form a permanent scar in the injured brain. As such, it is of great importance to understand the mechanism underlying the astrocytic response to injury, and this understanding is currently limited by the in vitro environments available to scientists. Biomaterials such as nanofibres and hydrogels offer great potential for the development of superior, 3D cell culture environments in which to study astrocyte behavior and phenotype. The implementation of such in vitro environments with a particularly interdisciplinary approach can improve the field's understanding of astrocytes, their role in central nervous system inflammation, and elucidate potential strategies to achieve functional regeneration.


Assuntos
Astrócitos/citologia , Encéfalo/citologia , Técnicas de Cultura de Células , Doenças do Sistema Nervoso Central/patologia , Medula Espinal/citologia , Alicerces Teciduais , Animais , Astrócitos/fisiologia , Diferenciação Celular , Humanos , Hidrogéis , Inflamação/patologia , Nanofibras
9.
Nat Commun ; 14(1): 457, 2023 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-36709345

RESUMO

Injectable biomimetic hydrogels have great potential for use in regenerative medicine as cellular delivery vectors. However, they can suffer from issues relating to hypoxia, including poor cell survival, differentiation, and functional integration owing to the lack of an established vascular network. Here we engineer a hybrid myoglobin:peptide hydrogel that can concomitantly deliver stem cells and oxygen to the brain to support engraftment until vascularisation can occur naturally. We show that this hybrid hydrogel can modulate cell fate specification within progenitor cell grafts, resulting in a significant increase in neuronal differentiation. We find that the addition of myoglobin to the hydrogel results in more extensive innervation within the host tissue from the grafted cells, which is essential for neuronal replacement strategies to ensure functional synaptic connectivity. This approach could result in greater functional integration of stem cell-derived grafts for the treatment of neural injuries and diseases affecting the central and peripheral nervous systems.


Assuntos
Hidrogéis , Células-Tronco Neurais , Hidrogéis/metabolismo , Oxigênio/metabolismo , Mioglobina/metabolismo , Células-Tronco Neurais/metabolismo , Neurônios/metabolismo , Diferenciação Celular
10.
medRxiv ; 2023 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-37609267

RESUMO

The differentiation of dengue virus (DENV) infection, a major cause of acute febrile illness in tropical regions, from other etiologies, may help prioritize laboratory testing and limit the inappropriate use of antibiotics. While traditional clinical prediction models focus on individual patient-level parameters, we hypothesize that for infectious diseases, population-level data sources may improve predictive ability. To create a clinical prediction model that integrates patient-extrinsic data for identifying DENV among febrile patients presenting to a hospital in Thailand, we fit random forest classifiers combining clinical data with climate and population-level epidemiologic data. In cross validation, compared to a parsimonious model with the top clinical predictors, a model with the addition of climate data, reconstructed susceptibility estimates, force of infection estimates, and a recent case clustering metric, significantly improved model performance.

11.
Psychol Med ; 42(11): 2433-44, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22717172

RESUMO

BACKGROUND: When gambling opportunities are made available to the public in a given jurisdiction, some individuals participate occasionally and others more frequently. Among frequent gamblers, some individuals develop problematic involvement and some do not. This study addresses the association among demographic and social risk factors, frequency of gambling and gambling disorders. METHOD: Data from an adult community sample (n=1372) were used to identify risk factors for higher-frequency gambling and disordered gambling involvement. RESULTS: Individuals with higher intelligence, older individuals and more religious individuals were less frequent gamblers. Males, single individuals and those exposed to gambling environments (friends and family who gamble) and those who started to gamble at a younger age were more frequent gamblers. Excitement-seeking personality traits were also higher among more frequent gamblers. A different set of risk factors was associated with the likelihood of gambling disorder among these higher-frequency gamblers. These variables included mental health indicators, childhood maltreatment and parental gambling involvement. Among higher-frequency gamblers, individuals who smoke cigarettes, those with a diagnosis of alcohol or drug dependence or obsessive-compulsive disorder, those with higher anxiety or depression and those with higher impulsivity and antisocial personality traits were more likely to report gambling-related problems. These individuals were also more likely to report gambling on electronic gambling machines (e.g. slot machines). CONCLUSIONS: These data suggest a model in which higher-frequency gambling, particularly with electronic gambling machines, when combined with any type of emotional vulnerability increased the likelihood of gambling disorder.


Assuntos
Jogo de Azar/epidemiologia , Adulto , Alberta/epidemiologia , Comorbidade , Feminino , Jogo de Azar/etiologia , Jogo de Azar/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores Sexuais
12.
J Environ Manage ; 105: 66-75, 2012 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-22531752

RESUMO

Wildfires pose significant risks to people and human infrastructure worldwide. The treatment of fuel in landscapes may alter these risks but the magnitude of this effect on risk is poorly understood. Evidence from Australian Eucalyptus forests suggests that mitigation of risk using prescribed burning as a fuel treatment is partial because weather and fuel dynamics are conducive to regular high intensity fires. We further examine the response of risk to treatment in eucalypt forests using landscape simulation modelling. We model how five key measures of wildfire activity that govern risk to people and property may respond to variations in rate and spatial pattern of prescribed fire. We then model effects of predicted climate change (2050 scenarios) to determine how the response of risk to treatment is likely to be altered in the future. The results indicate that a halving of risk to people and property in these forests is likely to require treatment rates of 7-10% of the area of the landscape per annum. Projections of 2050 weather conditions under climate change further substantially diminished the effect of rate of treatment. A large increase in rates of treatment (i.e. circa. 50% over current levels) would be required to counteract these effects of climate change. Such levels of prescribed burning are unlikely to be financially feasible across eucalypt dominated vegetation in south eastern Australia. Despite policy imperatives to expand fuel treatment, a reduction rather than an elimination of risk will result. Multi-faceted strategies will therefore be required for the management of risk.


Assuntos
Ecossistema , Eucalyptus , Incêndios , Modelos Biológicos , Austrália , Simulação por Computador , Conservação dos Recursos Naturais/métodos , Agricultura Florestal/métodos , Medição de Risco
13.
J R Nav Med Serv ; 98(2): 19-22, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22970641

RESUMO

A 27-year-old Royal Marine presented to his sickbay following two episodes of sudden onset visual disturbance. A subsequent MRI Scan demonstrated ischaemic changes in the territory of his right posterior cerebral artery. Transthoracic echocardiography was normal but a bubble contrast study was strongly positive indicating the presence of a relatively large patent foramen ovale (PFO). He underwent endovascular closure of his patent foramen ovale and was subsequently upgraded back to full duties. A 35-year-old Army Sergeant presented with sudden onset collapse, right sided weakness, dysarthria and confusion. He was airlifted to a Host Nation hospital and following a normal CT head underwent thrombolysis in the Emergency Department. This was unsuccessful but a CT guided embolectomy led to complete resolution of symptoms. Subsequent transthoracic echo revealed a PFO. He underwent endovascular closure and has since been returned to full duties. The incidence of PFO is common affecting 27% of the population but the incidence of ischaemic stroke in young adults (aged 15-45 years old) is rare. This maybe linked to the size of the PFOs in symptomatic individuals. These case reports emphasise the requirement for further investigation of individuals presenting with collapse and persisting neurology. Differential diagnosis and initial management for primary care and pre-hospital clinicians is also reviewed.


Assuntos
Forame Oval Patente/diagnóstico , Militares , Adulto , Diagnóstico Diferencial , Embolia Paradoxal/complicações , Procedimentos Endovasculares , Forame Oval Patente/complicações , Forame Oval Patente/terapia , Humanos , Masculino , Acidente Vascular Cerebral/etiologia
14.
JMIR Perioper Med ; 5(1): e35584, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34887242

RESUMO

BACKGROUND: The COVID-19 pandemic caused by the SARS-COV-2 virus has resulted in unprecedented challenges for the health care system. A decrease of surgical services led to substantial backlogs for time-sensitive scheduled pediatric patients. We designed and implemented a novel pilot weekend surgical quality improvement project called Operating Room Ramp-Up After COVID Lockdown Ends-Extra Lists (ORRACLE-Xtra). OBJECTIVE: Our overall goals are to increase patient access to surgery (and reduce the wait list), improve operating room efficiencies, and optimize parent and staff experience. METHODS: Using the DMAIC (define, measure, analyze, improve, control) framework, we implemented ORRACLE-Xtra in a tertiary care academic pediatric hospital during a quiescent period of the COVID-19 pandemic. We defined process and outcome measures based on provincial targets of out-of-window cases. Parental and staff satisfaction was tracked by surveys. RESULTS: ORRACLE-Xtra led to 247 patients receiving surgery during the pilot period, resulting in a 5% decrease in the total number of patients on our wait list with Paediatric Canadian Access Targets for Surgery IV (147/247, 59.5%), with 38.1% (94/247) out-of-window of provincial targets. Most of the process and outcome measures were met or exceeded. Overall parental satisfaction was at 95.8% (110/121), with 79% (64/81) of staff reporting satisfaction with working weekends. CONCLUSIONS: Through the ORRACLE-Xtra pilot program, we have shown that hospitals impacted by COVID-19 can reduce the surgical backlog using innovative models of service delivery in a Canadian context. Sustained funding is critical to achieving more meaningful reductions in wait times for scheduled surgeries over the longer term and needs to be balanced with staff well-being.

15.
J Theor Biol ; 268(1): 146-59, 2011 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-20869970

RESUMO

The general features of theoretical biology are outlined, starting from the beginnings of modern bioenergetics, energy transduction, in 1961. The major characteristics of the bioenergetic systems are then described and it is pointed out that especially the treatment of energized, directed chemical flow in divided space in cells is central to this activity. It is also the major theoretical problem of many other cellular activities. The development of bioenergetics until today, based on the theories of flows of electrons, protons and other chemical materials in structures, is then outlined. Great benefit has accrued from the knowledge of the structures which allow controlled flow, diffusion. In a speculative forward look at the theoretical biology of cells based on this outline the usefulness of further reductive analysis of extracted molecular units is considered as descriptions of mobility within structures of large molecules and membranes as well as in free space. Such structures are central to catalysed control and flow. The possibility of a more holistic approach is then examined. This will require markers of flow states and spatial structures. It is shown that as the flow system is one of a combined environment and organisms the study of metal ions in both has particular advantages. Consideration is given as to how this study can assist a broad understanding of the chemistry of the evolution of organisms. The changes of the metallome, strongly linked to the proteome, the genome and the environment, is a ready source of information concerning the manner in which changes in catalysts and controls of flow of organic chemicals have evolved in the divided space of cells and of cellular systems. The connection of the code changes to the environment via the metallome changes is then mooted.


Assuntos
Evolução Biológica , Metabolismo Energético/fisiologia , Compostos Orgânicos/metabolismo , Transdução de Sinais/fisiologia , Animais , Humanos , Metais/metabolismo , Modelos Biológicos , Oxigênio/metabolismo , Fatores de Tempo
17.
Nature ; 324(6097): 565-567, 1986 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-29517725

RESUMO

The tailoring of inorganic minerals such as iron oxides for functional use in biological systems for iron storage1, structural support2 and magnetoreception3 involves biological regulation of crystal structure, particle size, morphology and crystallographic organization. The encapsulation of crystallochemical reactions within enclosed biological microvolumes enables control to be exerted over: (1) the chemical regulation, by passive or facilitated ion-transport, of localised supersaturation levels (2) the stereochemical requirements for ion-binding, redox and nucleation events at the organic matrix interface and (3) the spatial organization of crystal growth and morphology4,5. Matrix-mediated growth of inorganic materials has not been systematically investigated in vitro even though it may have applications in crystal engineering and materials science6. We have used phospholipid unilamellar vesicles of ∼300 Šdiameter to study membrane-mediated processes of iron oxide crystal growth. Intravesicular deposits differ in structure, morphology and size from precipitates formed from reactions in bulk aqueous solution. Mediating factors include vesicle shape and dimension, diffusion-limited processes of ion-transport and ion-binding at the curved lipid headgroup surface. These results help elucidate biomineralization and have technological relevance to the controlled synthesis of monodisperse sols with catalytic and magnetic properties.

18.
Scott Med J ; 55(1): 24-6, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20218276

RESUMO

BACKGROUND: Professional guidelines and clinical practice regarding use of chaperones vary substantially in different health care settings. Although there are several studies in primary care practice, no such studies are available in a breast care setting. We have undertaken a questionnaire survey of practicing consultant breast surgeons in the U.K. regarding the use of a chaperone during breast examination. METHOD: A self-completion questionnaire, with 18 items was developed, piloted, modified and mailed to 400 consultant breast surgeons across the U.K. RESULT: 302/400 questionnaires were returned (76%). Sixty-five per cent had a policy on the use of chaperone. Although 73% always offer a chaperone, the majority never documented the offer (74%) or identity (73%). Overall use of chaperone was significantly higher among male (82%), compared to female surgeons (38%, p < 0.001). The majority said that patient embarrassment (54%) and the availability of a nurse (57%) strongly influence chaperone use unlike patient's age, marital status, ethnicity, anxiety, instinct. Seventy per cent of respondents believed that the presence of a chaperone was important for medico-legal protection of doctor and patient (55%). CONCLUSION: Our study shows that the majority of consultant breast surgeons in the UK use a chaperone. The overall use of a chaperone in secondary breast care setting is higher compared to previous studies in primary care. Documentation of the offer and identity of the chaperone is very poor.


Assuntos
Atitude do Pessoal de Saúde , Doenças Mamárias/diagnóstico , Exame Físico , Encaminhamento e Consulta/organização & administração , Adulto , Fatores Etários , Doenças Mamárias/cirurgia , Feminino , Fidelidade a Diretrizes , Humanos , Masculino , Mastectomia , Pessoa de Meia-Idade , Relações Médico-Paciente , Fatores Sexuais , Reino Unido
19.
Interface Focus ; 10(2): 20190090, 2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-32194933

RESUMO

As the field of tissue engineering continues to advance rapidly, so too does the complexity of cell culture techniques used to generate in vitro tissue constructs, with the overall aim of mimicking the in vivo microenvironment. This complexity typically comes at a cost with regards to the size of the equipment required and associated expenses. We have developed a small, low-cost bioreactor system which overcomes some of the issues of typical bioreactor systems while retaining a suitable scale for the formation of complex tissues. Herein, we have tested this system with three cell populations/tissues: the culture of hepatocellular carcinoma cells, where an improved structure and basic metabolic function is seen; the culture of human pluripotent stem cells, in which the cultures can form more heterogeneous tissues resembling the in vivo teratoma and ex vivo liver tissue slices, in which improved maintenance of cellular viability is seen over the 3 days tested. This system has the flexibility to be used for a variety of further uses and has the potential to provide a more accessible alternative to current bioreactor technologies.

20.
Int J Sports Med ; 30(9): 663-7, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19585403

RESUMO

Gender differences in hip and core strength and range of motion may contribute to the gender based variance in injury risk. This study was designed to test the primary hypothesis that hip and core strength, flexibility and lower extremity dynamic alignment differ in male and female soccer athletes. Ninety-eight collegiate soccer players (54 male, 44 female) participated in this study. Athletes were evaluated for hip range of motion, and hip and abdominal strength. Both male and female soccer players demonstrated limited hip rotation, with less hip internal rotation in males (p<0.0001), and poor abdominal core control, although the males are stronger (p=0.02). Overall hip ROM is shifted towards internal rotation in females compared to males. Female soccer players also have a significant side-to-side disparity in hip abductor strength (p<0.0001), not present in males. The shift in hip ROM towards internal rotation combined with the hip abductor imbalance may be associated with a position of ACL risk with internally rotated hips and valgus knees in female soccer players. Limitations in hip and core strength and range of motion may play a role in the disparity between the male and female rate of ACL injury.


Assuntos
Músculos Abdominais/fisiologia , Articulação do Quadril/fisiologia , Amplitude de Movimento Articular/fisiologia , Futebol/fisiologia , Adolescente , Lesões do Ligamento Cruzado Anterior , Feminino , Humanos , Articulação do Joelho/fisiologia , Masculino , Risco , Rotação , Fatores Sexuais , Adulto Jovem
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