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BACKGROUND: Cardiac repair and remodeling following myocardial infarction (MI) is a multifactorial process involving pro-reparative inflammation, angiogenesis and fibrosis. Noninvasive imaging using a radiotracer targeting these processes could be used to elucidate cardiac wound healing mechanisms. The alpha7 nicotinic acetylcholine receptor (É7nAChR) stimulates pro-reparative macrophage activity and angiogenesis, making it a potential imaging biomarker in this context. We investigated this by assessing in vitro cellular expression of É7nAChR, and by using a tritiated version of the PET radiotracer [18F]NS14490 in tissue autoradiography studies. RESULTS: É7nAChR expression in human monocyte-derived macrophages and vascular cells showed the highest relative expression was within macrophages, but only endothelial cells exhibited a proliferation and hypoxia-driven increase in expression. Using a mouse model of inflammatory angiogenesis following sponge implantation, specific binding of [3H]NS14490 increased from 3.6 ± 0.2 µCi/g at day 3 post-implantation to 4.9 ± 0.2 µCi/g at day 7 (n = 4, P < 0.01), followed by a reduction at days 14 and 21. This peak matched the onset of vessel formation, macrophage infiltration and sponge fibrovascular encapsulation. In a rat MI model, specific binding of [3H]NS14490 was low in sham and remote MI myocardium. Specific binding within the infarct increased from day 14 post-MI (33.8 ± 14.1 µCi/g, P ≤ 0.01 versus sham), peaking at day 28 (48.9 ± 5.1 µCi/g, P ≤ 0.0001 versus sham). Histological and proteomic profiling of É7nAChR positive tissue revealed strong associations between É7nAChR and extracellular matrix deposition, and rat cardiac fibroblasts expressed É7nAChR protein under normoxic and hypoxic conditions. CONCLUSION: É7nAChR is highly expressed in human macrophages and showed proliferation and hypoxia-driven expression in human endothelial cells. While NS14490 imaging displays a pattern that coincides with vessel formation, macrophage infiltration and fibrovascular encapsulation in the sponge model, this is not the case in the MI model where the É7nAChR imaging signal was strongly associated with extracellular matrix deposition which could be explained by É7nAChR expression in fibroblasts. Overall, these findings support the involvement of É7nAChR across several processes central to cardiac repair, with fibrosis most closely associated with É7nAChR following MI.
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Within microeukaryotes, genetic variation and functional variation sometimes accumulate more quickly than morphological differences. To understand the evolutionary history and ecology of such lineages, it is key to examine diversity at multiple levels of organization. In the dinoflagellate family Symbiodiniaceae, which can form endosymbioses with cnidarians (e.g., corals, octocorals, sea anemones, jellyfish), other marine invertebrates (e.g., sponges, molluscs, flatworms), and protists (e.g., foraminifera), molecular data have been used extensively over the past three decades to describe phenotypes and to make evolutionary and ecological inferences. Despite advances in Symbiodiniaceae genomics, a lack of consensus among researchers with respect to interpreting genetic data has slowed progress in the field and acted as a barrier to reconciling observations. Here, we identify key challenges regarding the assessment and interpretation of Symbiodiniaceae genetic diversity across three levels: species, populations, and communities. We summarize areas of agreement and highlight techniques and approaches that are broadly accepted. In areas where debate remains, we identify unresolved issues and discuss technologies and approaches that can help to fill knowledge gaps related to genetic and phenotypic diversity. We also discuss ways to stimulate progress, in particular by fostering a more inclusive and collaborative research community. We hope that this perspective will inspire and accelerate coral reef science by serving as a resource to those designing experiments, publishing research, and applying for funding related to Symbiodiniaceae and their symbiotic partnerships.
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Recifes de Corais , Dinoflagellida , Variação Genética , Dinoflagellida/classificação , Dinoflagellida/genética , Filogenia , Consenso , Antozoários , SimbioseRESUMO
While research suggests that COVID-19 vaccines are effective in producing anti-SARS-CoV-2 antibodies that reduce the risk of COVID-19 and its potentially severe complications, how long these antibodies persist after the infection/vaccination is unknown. Longitudinal studies and rapid and scalable platforms are needed for large-scale sero-diagnosis and vaccine evaluation. In this study, we examine the efficacy of our recently-developed handheld thermo-photonic device for rapid and low-cost assessment of the adaptive immune response of COVID+ and COVID- patients admitted to the intensive care unit (ICU) at a local hospital due to respiratory deterioration. Antibody testing included detection and quantification of IgG and IgM via thermo-photonic sensing of a commercially available COVID-19 IgG/IgM rapid test as well as standard measurements with quantitative enzyme-linked immunosorbent assays (qELISA). The results demonstrate that the thermo-photonic reader in conjunction with COVID-19 IgG/IgM test cassettes can detect and quantify IgG levels in COVID-19 antibody assays within the clinically relevant range and with a high correlation to those obtained from qELISA. We also found that the IgG antibody is more reliable for detecting individuals with an adaptive immune response to SARS-CoV-2 compared to the IgM antibody. The developed reader offers a low-cost, portable, and scalable solution for accessing the antibody titer of individuals against SARS-CoV-2 and can be used in local hospital settings.
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Targeted blood pressure (BP) control is a goal of left ventricular assist device medical management, but the interpretation of values obtained from noninvasive instruments is challenging. In the MOMENTUM 3 Continued Access Protocol, paired BP values in HeartMate 3 (HM3) patients were compared from arterial (A)-line and Doppler opening pressure (DOP) (319 readings in 261 patients) and A-line and automated cuff (281 readings in 247 patients). Pearson (R) correlations between A-line mean arterial (MAP) and systolic blood pressures (SBP) were compared with DOP and cuff measures according to the presence (>1 pulse in 5 seconds) or absence of a palpable radial pulse. There were only moderate correlations between A-line and noninvasive measurements of SBP (DOP R = 0.58; cuff R = 0.47) and MAP (DOP R = 0.48; cuff R = 0.37). DOP accuracy for MAP estimation, defined as the % of readings within ± 10 mmHg of A-line MAP, decreased from 80% to 33% for DOP ≤ 90 vs. >90 mmHg, and precision also diminished (mean absolute difference [MAD] increased from 6.3 ± 5.6 to 16.1 ± 11.4 mmHg). Across pulse pressures, cuff MAPs were within ±10 mmHg of A-line 62.9%-68.8% of measures and MADs were negligible. The presence of a palpable pulse reduced the accuracy and precision of the DOP-MAP estimation but did not impact cuff-MAP accuracy or precision. In summary, DOP may overestimate MAP in some patients on HM3 support. Simultaneous use of DOP and automated cuff and radial pulse may be needed to guide antihypertensive medication titration in outpatients on HM3 support.
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Determinação da Pressão Arterial , Coração Auxiliar , Pressão Sanguínea/fisiologia , Frequência Cardíaca , Coração Auxiliar/efeitos adversos , Humanos , Ultrassonografia Doppler/métodosRESUMO
OBJECTIVE: In a proof-of-concept study, to quantify myocardial viability in patients with acute myocardial infarction using manganese-enhanced MRI (MEMRI), a measure of intracellular calcium handling. METHODS: Healthy volunteers (n=20) and patients with ST-elevation myocardial infarction (n=20) underwent late gadolinium enhancement (LGE) using gadobutrol and MEMRI using manganese dipyridoxyl diphosphate. Patients were scanned ≤7 days after reperfusion and rescanned after 3 months. Differential manganese uptake was described using a two-compartment model. RESULTS: After manganese administration, healthy control and remote non-infarcted myocardium showed a sustained 25% reduction in T1 values (mean reductions, 288±34 and 281±12 ms). Infarcted myocardium demonstrated less T1 shortening than healthy control or remote myocardium (1157±74 vs 859±36 and 835±28 ms; both p<0.0001) with intermediate T1 values (1007±31 ms) in peri-infarct regions. Compared with LGE, MEMRI was more sensitive in detecting dysfunctional myocardium (dysfunctional fraction 40.5±11.9 vs 34.9%±13.9%; p=0.02) and tracked more closely with abnormal wall motion (r2=0.72 vs 0.55; p<0.0001). Kinetic modelling showed reduced myocardial manganese influx between remote, peri-infarct and infarct regions, enabling absolute discrimination of infarcted myocardium. After 3 months, manganese uptake increased in peri-infarct regions (16.5±3.5 vs 22.8±3.5 mL/100 g/min, p<0.0001), but not the remote (23.3±2.8 vs 23.0±3.2 mL/100 g/min, p=0.8) or infarcted (11.5±3.7 vs 14.0±1.2 mL/100 g/min, p>0.1) myocardium. CONCLUSIONS: Through visualisation of intracellular calcium handling, MEMRI accurately differentiates infarcted, stunned and viable myocardium, and correlates with myocardial dysfunction better than LGE. MEMRI holds major promise in directly assessing myocardial viability, function and calcium handling across a range of cardiac diseases. TRIAL REGISTRATION NUMBERS: NCT03607669; EudraCT number 2016-003782-25.
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Ácido Edético/análogos & derivados , Imagem Cinética por Ressonância Magnética/métodos , Miocárdio Atordoado/diagnóstico , Miocárdio/patologia , Fosfato de Piridoxal/análogos & derivados , Adulto , Cálcio/metabolismo , Meios de Contraste/farmacologia , Ácido Edético/farmacologia , Feminino , Seguimentos , Humanos , Espaço Intracelular/metabolismo , Masculino , Manganês , Pessoa de Meia-Idade , Miocárdio Atordoado/metabolismo , Miocárdio/metabolismo , Fosfato de Piridoxal/farmacologia , Estudos RetrospectivosRESUMO
Cardiovascular disease (CVD) remains the leading cause of death worldwide and, despite continuous advances, better diagnostic and prognostic tools, as well as therapy, are needed. The human transcriptome, which is the set of all RNA produced in a cell, is much more complex than previously thought and the lack of dialogue between researchers and industrials and consensus on guidelines to generate data make it harder to compare and reproduce results. This European Cooperation in Science and Technology (COST) Action aims to accelerate the understanding of transcriptomics in CVD and further the translation of experimental data into usable applications to improve personalized medicine in this field by creating an interdisciplinary network. It aims to provide opportunities for collaboration between stakeholders from complementary backgrounds, allowing the functions of different RNAs and their interactions to be more rapidly deciphered in the cardiovascular context for translation into the clinic, thus fostering personalized medicine and meeting a current public health challenge. Thus, this Action will advance studies on cardiovascular transcriptomics, generate innovative projects, and consolidate the leadership of European research groups in the field.COST (European Cooperation in Science and Technology) is a funding organization for research and innovation networks (www.cost.eu).
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INTRODUCTION: Adenotonsillectomy (T&A) has been associated with postoperative weight gain in children. The purpose of this study is to determine whether a similar association exists in children with Down syndrome (DS). METHODS: The medical records of 311 DS patients were reviewed. Subjects were classified into either a control group or surgical group based on whether they had undergone adenotonsillectomy (T&A). Subjects were excluded if they only had one recorded BMI. Cases were analyzed in a pairwise fashion to maximize available data. 113 total patients with DS were identified: 84 (74.3%) in the control group and 29 (25.7%) in the T&A group. Height, weight, BMI, and Z-score data were compared between the control and T&A groups at 6-month intervals over a 24-month period. RESULTS: Children with DS who underwent T&A were comparable by demographics to children with DS who did not undergo T&A. Mean weight gain at 24 months for the T&A group was 8.07 ± 5.66 kg compared with 5.76 ± 13.20 kg in controls. The median Z-score at 24 months for the T&A group was 1.11 (0.10-1.88) compared with 1.17 (0.80-1.75) in controls. Children undergoing T&A had a stable median Z-score change of 0.09 at 24 months (p = 0.861, compared to baseline) while children who did not undergo T&A had a significantly increased median Z-score of 0.52 (p = 0.035, compared to baseline). Despite this, there were no significant intergroup differences between weight change, BMI, nor Z-score at any interval (p > 0.05). CONCLUSIONS AND RELEVANCE: Children with DS did not have an increased rate of weight gain or increased BMI after T&A. BMI Z-scores were shown to stabilize over 24 months in the T&A group and increase in the control group. While this suggests that T&A provides an added benefit of weight control in patients with DS, the results should be interpreted with caution due to the small sample size and the fact that not all patients had complete follow up across a 24-month period.
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Adenoidectomia/efeitos adversos , Síndrome de Down/cirurgia , Tonsilectomia/efeitos adversos , Aumento de Peso , Adenoidectomia/métodos , Índice de Massa Corporal , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Período Pós-Operatório , Tonsilectomia/métodosRESUMO
OBJECTIVE: Preclinical evaluation of hernia meshes is commonly performed in porcine models. We recently developed two surgically induced porcine hernia models-an incisional and an excisional model-that formed persistent hernias in the absence of graft repair. Herein, we investigate if these models will continue to form a hernia after graft repair. MATERIALS AND METHODS: Ten pigs were used to create two hernia models-a 10-cm partial-thickness incisional defect (n = 5) and an 8 × 8-cm full-thickness excisional defect (n = 5). The defects were repaired using a 12 × 12-cm human acellular dermis graft placed in a preperitoneal/retrorectus sublay position and fixed using transfascial sutures. Postoperative management included the use of suction drainage for 1 week and an abdominal binder for 4 weeks in the more severe excisional model. Hernia development was assessed clinically, and hernia defect size and volume were measured using postoperative computed tomography (CT) imaging over 12 weeks. Radiographic inflation testing (2 L inflation), biaxial mechanical testing, and histological evaluation were also performed at 12 weeks. RESULTS: All pigs with the excisional model, but none with the incisional model, developed a clinically relevant hernia. At the end of 12 weeks, the excisional model had a significantly greater hernia defect size (259 ± 51 cm2 vs. 47 ± 16 cm2) and repair volume (865 ± 414 cm3 vs. 85 ± 52 cm3) compared with the incisional model. The excisional model also showed an order of magnitude greater increase in repair volume (280 cm3 vs. 47 cm3) compared with the incisional model upon 2 L inflation. Furthermore, the excisional model showed a trend of having higher dilatational strain at average biaxial load of 250 N and lower stiffness compared with the incisional model. The excisional model had a thin, hypercellular hernia sac spanning the defect, whereas the incisional model had a thick densely fibrotic scar bridging the defect. CONCLUSION: The 8 × 8-cm excisional defect model, together with appropriate postoperative wound management, in the pig model is recommended for preclinical investigation of different grafts for hernia repair. Novel CT imaging and biomechanical testing methods are recommended to measure functional outcomes of hernia repair in preclinical models.
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Derme Acelular/metabolismo , Hérnia Ventral/terapia , Herniorrafia , Animais , Modelos Animais de Doenças , Determinação de Ponto Final , Feminino , Humanos , Sus scrofa , Tomografia Computadorizada por Raios XRESUMO
BACKGROUND: Despite their potential interest for clinical management, measurements of respiratory mechanics in patients with acute respiratory distress syndrome (ARDS) are seldom performed in routine practice. We introduced a systematic assessment of respiratory mechanics in our clinical practice. After the first year of clinical use, we retrospectively assessed whether these measurements had any influence on clinical management and physiological parameters associated with clinical outcomes by comparing their value before and after performing the test. METHODS: The respiratory mechanics assessment constituted a set of bedside measurements to determine passive lung and chest wall mechanics, response to positive end-expiratory pressure, and alveolar derecruitment. It was obtained early after ARDS diagnosis. The results were provided to the clinical team to be used at their own discretion. We compared ventilator settings and physiological variables before and after the test. The physiological endpoints were oxygenation index, dead space, and plateau and driving pressures. RESULTS: Sixty-one consecutive patients with ARDS were enrolled. Esophageal pressure was measured in 53 patients (86.9%). In 41 patients (67.2%), ventilator settings were changed after the measurements, often by reducing positive end-expiratory pressure or by switching pressure-targeted mode to volume-targeted mode. Following changes, the oxygenation index, airway plateau, and driving pressures were significantly improved, whereas the dead-space fraction remained unchanged. The oxygenation index continued to improve in the next 48 h. CONCLUSIONS: Implementing a systematic respiratory mechanics test leads to frequent individual adaptations of ventilator settings and allows improvement in oxygenation indexes and reduction of the risk of overdistention at the same time. TRIAL REGISTRATION: The present study involves data from our ongoing registry for respiratory mechanics (ClinicalTrials.gov identifier: NCT02623192 . Registered 30 July 2015).
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Testes Imediatos , Síndrome do Desconforto Respiratório/diagnóstico , Mecânica Respiratória/fisiologia , Pesos e Medidas/normas , Idoso , Ensaios Clínicos como Assunto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Padrões de Prática Médica/normas , Respiração Artificial/métodos , Respiração Artificial/normas , Estudos RetrospectivosRESUMO
AIM: The cognitive, emotional, behavioral and physical impairments experienced by adults after mild traumatic brain injury (mTBI) can produce substantial disability, with 15-20% requiring referral to tertiary care (TC) for persistent symptoms. METHODS: A convenience sample of 201 adult patients referred to TC as a result of mTBI was studied. Self-reported data were collected at first TC visit, on average 10 months postinjury. Patients reported the type and intensity of healthcare provider visit(s) undertaken while awaiting TC. RESULTS: On average males reported 37 and females 30 healthcare provider visits, resulting in over $500,000 Canadian dollars spent on potentially excess mTBI care over 1 year. DISCUSSION: Based on conservative estimate of 15% of mTBI patients receiving TC, this finding identifies a possible excess in care of $110 million for Ontario. Accurate diagnosis of mTBI and early coordination of follow-up care for those needing TC could increase cost-effectiveness.
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Important challenges for the diagnosis and monitoring of mild traumatic brain injury (mTBI) include the development of plasma biomarkers for assessing neurologic injury, monitoring pathogenesis, and predicting vulnerability for the development of untoward neurologic outcomes. While several biomarker proteins have shown promise in this regard, used individually, these candidates lack adequate sensitivity and/or specificity for making a definitive diagnosis or identifying those at risk of subsequent pathology. The objective for this study was to evaluate a panel of six recognized and novel biomarker candidates for the assessment of TBI in adult patients. The biomarkers studied were selected on the basis of their relative brain-specificities and potentials to reflect distinct features of TBI mechanisms including (1) neuronal damage assessed by neuron-specific enolase (NSE) and brain derived neurotrophic factor (BDNF); (2) oxidative stress assessed by peroxiredoxin 6 (PRDX6); (3) glial damage and gliosis assessed by glial fibrillary acidic protein and S100 calcium binding protein beta (S100b); (4) immune activation assessed by monocyte chemoattractant protein 1/chemokine (C-C motif) ligand 2 (MCP1/CCL2); and (5) disruption of the intercellular adhesion apparatus assessed by intercellular adhesion protein-5 (ICAM-5). The combined fold-changes in plasma levels of PRDX6, S100b, MCP1, NSE, and BDNF resulted in the formulation of a TBI assessment score that identified mTBI with a receiver operating characteristic (ROC) area under the curve of 0.97, when compared to healthy controls. This research demonstrates that a profile of biomarker responses can be used to formulate a diagnostic score that is sensitive for the detection of mTBI. Ideally, this multivariate assessment strategy will be refined with additional biomarkers that can effectively assess the spectrum of TBI and identify those at particular risk for developing neuropathologies as consequence of a mTBI event.
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BACKGROUND: Cardiovascular disorders, including coronary artery bypass graft failure and in-stent restenosis remain significant opportunities for the advancement of novel therapeutics that target neointimal hyperplasia, a characteristic of both pathologies. Gene therapy may provide a successful approach to improve the clinical outcome of these conditions, but would benefit from the development of more efficient vectors for vascular gene delivery. The aim of this study was to assess whether a novel genetically engineered Adenovirus could be utilised to produce enhanced levels of vascular gene expression. METHODS: Vascular transduction capacity was assessed in primary human saphenous vein smooth muscle and endothelial cells using vectors expressing the LacZ reporter gene. The therapeutic capacity of the vectors was compared by measuring smooth muscle cell metabolic activity and migration following infection with vectors that over-express the candidate therapeutic gene tissue inhibitor of matrix metalloproteinase-3 (TIMP-3). RESULTS: Compared to Adenovirus serotype 5 (Ad5), the novel vector Ad5T*F35++ demonstrated improved binding and transduction of human vascular cells. Ad5T*F35++ mediated expression of TIMP-3 reduced smooth muscle cell metabolic activity and migration in vitro. We also demonstrated that in human serum samples pre-existing neutralising antibodies to Ad5T*F35++ were less prevalent than Ad5 neutralising antibodies. CONCLUSIONS: We have developed a novel vector with improved vascular transduction and improved resistance to human serum neutralisation. This may provide a novel vector platform for human vascular gene transfer.
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Adenoviridae/genética , Técnicas de Transferência de Genes , Vetores Genéticos , Capsídeo , Células Cultivadas , Humanos , Veia Safena , Inibidor Tecidual de Metaloproteinase-3/análise , Inibidor Tecidual de Metaloproteinase-3/farmacologia , Transdução Genética , beta-Galactosidase/análiseRESUMO
Prostaglandins (PG) and isoprostanes (iso-PG) may be derived through cyclooxygenase or free radical pathways and are important signaling molecules that are also robust biomarkers of oxidative stress. Their quantification is important for understanding many biological processes where PG, iso-PG, or oxidative stress are involved. One of the common methods for PG and iso-PG quantifications is LC-MS/MS that allows a highly selective, sensitive, simultaneous analysis for prostanoids without derivatization. However, the currently used LC-MS/MS methods require a multi-step extraction and a long (within an hour) LC separation to achieve simultaneous separation and analysis of the major iso-PG. The developed and validated for brain tissue analysis one-step extraction protocol and UPLC-MS/MS method significantly increases the recovery of the PG extraction up to 95 %, and allows for a much faster (within 4 min) major iso-PGE2 and -PGD2 separation with 5 times narrower chromatographic peaks as compared to previously used methods. In addition, it decreases the time and cost of analysis due to the one-step extraction approach performed in disposable centrifuge tubes. All together, this significantly increases the sensitivity, and the time and cost efficiency of the PG and iso-PG analysis.
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Química Encefálica , Cromatografia Líquida de Alta Pressão/métodos , Isoprostanos/isolamento & purificação , Prostaglandinas/isolamento & purificação , Espectrometria de Massas em Tandem/métodos , Animais , Cromatografia Líquida de Alta Pressão/economia , Dinoprostona/análise , Dinoprostona/isolamento & purificação , Isoprostanos/análise , Limite de Detecção , Masculino , Camundongos , Prostaglandina D2/análise , Prostaglandina D2/isolamento & purificação , Prostaglandinas/análise , Espectrometria de Massas em Tandem/economia , Fatores de TempoRESUMO
OBJECTIVES: To investigate patients' and family members' perceptions and experiences of disclosure of healthcare incidents and to derive principles of effective disclosure. DESIGN: Retrospective qualitative study based on 100 semi-structured, in depth interviews with patients and family members. SETTING: Nationwide multisite survey across Australia. PARTICIPANTS: 39 patients and 80 family members who were involved in high severity healthcare incidents (leading to death, permanent disability, or long term harm) and incident disclosure. Recruitment was via national newspapers (43%), health services where the incidents occurred (28%), two internet marketing companies (27%), and consumer organisations (2%). MAIN OUTCOME MEASURES: Participants' recurrent experiences and concerns expressed in interviews. RESULTS: Most patients and family members felt that the health service incident disclosure rarely met their needs and expectations. They expected better preparation for incident disclosure, more shared dialogue about what went wrong, more follow-up support, input into when the time was ripe for closure, and more information about subsequent improvement in process. This analysis provided the basis for the formulation of a set of principles of effective incident disclosure. CONCLUSIONS: Despite growing prominence of open disclosure, discussion about healthcare incidents still falls short of patient and family member expectations. Healthcare organisations and providers should strengthen their efforts to meet patients' (and family members') needs and expectations.
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Atitude Frente a Saúde , Revelação , Família/psicologia , Erros Médicos/psicologia , Relações Médico-Paciente , Adolescente , Adulto , Idoso , Austrália , Criança , Pré-Escolar , Compensação e Reparação , Coleta de Dados , Humanos , Lactente , Pessoa de Meia-Idade , Satisfação do Paciente , Percepção , Satisfação Pessoal , Apoio Social , Adulto JovemRESUMO
Animal shoulder models are used to systematically investigate the factors influencing rotator cuff injury and repair. Each model has advantages and disadvantages that must be considered in the context of the specific research questions being asked. This study evaluated the utility of the canine model for studies of acute, full-thickness rotator cuff tendon injury and repair. We found that time-zero failure load is dependent on the suture type and configuration used for repair. Acute, full-width tendon repairs fail anatomically within the first days after surgery in the canine model, regardless of suture type, suture configuration, or postoperative protocol. Robust scar tissue forms in the gap between the failed tendon end and the humerus, which can be visually, mechanically, and histologically misconstrued as tendon if an objective test of repair connectivity is not performed. We conclude that a full-width injury and repair model in the canine will provide a rigorous test of whether a new repair strategy or postoperative protocol, such as casting or temporary muscle paralysis, can maintain repair integrity in a high-load environment. Alternatively, a partial-width tendon injury model allows loads to be shared between the tendon repair and the remaining intact portion of the infraspinatus tendon and prohibits complete tendon retraction. Thus a partial-width injury in the canine may model the mechanical environment of many single tendon tears in the human injury condition and warrants further investigation.
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Modelos Animais de Doenças , Lesões do Manguito Rotador , Manguito Rotador/cirurgia , Traumatismos dos Tendões/fisiopatologia , Cicatrização/fisiologia , Animais , Cães , Endopeptidases , Técnicas de Sutura , SuturasRESUMO
OBJECTIVES: As most Canadians die in hospital, the final contact of family members with their loved ones is frequently in an unknown and uncomfortable environment. Family members are integral to the end-of-life decision-making process and are vital contributors to the comfort of dying patients. A quantitative study was conducted in three critical care areas where the stated goals were to provide not only quality care to patients, but also support to families. The researchers sought to determine levels of satisfaction with care, visitation, support, comfort and pain measures. METHOD: Three hundred surveys were mailed to next of kin who had a loved one die in the critical care areas of an urban tertiary care centre within the prior three years. Survey questions covered such issues as perceptions regarding the decision to stop life supports, access to the patient, access to physicians and nurses and information regarding the patient's status, support provided by the hospital, and organ donation attitudes. FINDINGS: Multiple regression analysis revealed that three factors predicted perceptions of overall quality of care: 1) being informed by nurses and physicians of any changes, 2) having the same group of nurses provide care, and 3) having one individual act as the family contact. Together these factors accounted for 52% of the variance in perceptions of care. Two factors accounted for 59% of the variance in dissatisfaction with the information received: 1) the perception that physicians did not spend enough time answering family questions, and 2) that the family was not present when the patient died. IMPLICATIONS: Consistency in nursing care and provision of information to family members may be difficult in the fast pace of an ICU, but are reasonable program objectives considering the positive influence this has on perceptions of care. Further, flexible visitation policies which maximize access between family members and both their dying loved one and health care professionals appear to have a beneficial effect on satisfaction.