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Physical examination education begins early for medical learners. A hindrance to physical exam competency is lack of exposure to pathology in standardized patient settings. This research focuses on improving medical education through the utilization of cadavers that have undergone a soft-embalming technique: the Thiel method. Three scenarios were created in four Thiel cadavers: anterior cruciate ligament (ACL) tear, posterior cruciate ligament (PCL) tear, and sham incision. Students were asked to diagnose ACL tears using the Lachman exam. A total of 54 learners participated in the study. Post-surveys indicated most learners: (1) prefer to use standardized patients (SPs) and soft-embalmed cadavers in their physical examination courses, (2) increased their confidence in performing the Lachman exam on real patients, and (3) enhanced their Lachman technique. SPs ultimately cannot volitionally reproduce the physical exam findings of ACL deficiency. Consequently, learners cannot accurately identify positive versus negative examination findings. Thiel-embalmed cadavers are a valuable resource for physical examination education. (Journal of Surgical Orthopaedic Advances 30(2):112-115, 2021).
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Lesões do Ligamento Cruzado Anterior , Embalsamamento , Lesões do Ligamento Cruzado Anterior/diagnóstico , Cadáver , Humanos , Exame Físico , Inquéritos e QuestionáriosRESUMO
The Antarctic is considered to be a pristine environment relative to other regions of the Earth, but it is increasingly vulnerable to invasions by marine, freshwater and terrestrial non-native species. The Antarctic Peninsula region (APR), which encompasses the Antarctic Peninsula, South Shetland Islands and South Orkney Islands, is by far the most invaded part of the Antarctica continent. The risk of introduction of invasive non-native species to the APR is likely to increase with predicted increases in the intensity, diversity and distribution of human activities. Parties that are signatories to the Antarctic Treaty have called for regional assessments of non-native species risk. In response, taxonomic and Antarctic experts undertook a horizon scanning exercise using expert opinion and consensus approaches to identify the species that are likely to present the highest risk to biodiversity and ecosystems within the APR over the next 10 years. One hundred and three species, currently absent in the APR, were identified as relevant for review, with 13 species identified as presenting a high risk of invading the APR. Marine invertebrates dominated the list of highest risk species, with flowering plants and terrestrial invertebrates also represented; however, vertebrate species were thought unlikely to establish in the APR within the 10 year timeframe. We recommend (a) the further development and application of biosecurity measures by all stakeholders active in the APR, including surveillance for species such as those identified during this horizon scanning exercise, and (b) use of this methodology across the other regions of Antarctica. Without the application of appropriate biosecurity measures, rates of introductions and invasions within the APR are likely to increase, resulting in negative consequences for the biodiversity of the whole continent, as introduced species establish and spread further due to climate change and increasing human activity.
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INTRODUCTION: Synovial fluid (SF) is in close proximity to tissues which are primarily altered during articular disease and has significant potential to better understand the underlying disease pathogeneses of articular pathologies and biomarker discovery. Although development of mass spectrometry-based methods has allowed faster and higher sensitivity techniques, interrogation of the SF proteome has been hindered by its large protein concentration dynamic range, impeding quantification of lower abundant proteins. Areas covered: Recent advances have developed methodologies to reduce the large protein concentration dynamic range of SF and subsequently allow deeper exploration of the SF proteome. This review concentrates on methods to overcome biofluid complexity, mass spectrometry proteomics methodologies, extracellular vesicles proteomics and the application of advances within the field in clinical disease, including osteoarthritis, rheumatoid arthritis, spondyloarthritis and juvenile arthritis. A narrative review was conducted with articles searched using PubMed, 1991-2018. Expert opinion: The SF proteomics field faces various challenges, including the requirement for rigorous and standardised methods of sample collection/storage, the sensitivity and specificity of proteomic assays, techniques to combat the large protein concentration dynamic range and comprehensive data analysis to reduce falsely identified markers. Additionally, there are challenges in developing multi 'omic' integration techniques, with computational integration enhancing analysis.
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Proteômica/métodos , Líquido Sinovial/metabolismo , Artrite/metabolismo , Artrite/terapia , Vesículas Extracelulares/metabolismo , Humanos , Espectrometria de Massas , Resultado do TratamentoRESUMO
Osteoid osteomas are typically benign osteoblastic bone tumors. Patients often present in their twenties with progressively increasing pain that is worse at night and relieved with nonsteroidal anti-inflammatory drugs. These lesions rarely occur in the hand or wrist; however, when those are involved, the proximal phalanx is the most common location and the index finger is the most commonly affected digit. Lesions affecting the distal phalanges are least likely to occur and the thumb is least likely to be affected. Osteoid osteomas of the distal phalanges can cause great diagnostic challenges. They often present with atypical radiographic and physical examination findings. Although rare, osteoid osteomas of the distal phalanx can be a major cause of digit enlargement and pain. In a patient with a painful and/or swollen digit, the diagnosis should be considered.
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Neoplasias Ósseas/cirurgia , Falanges dos Dedos da Mão/patologia , Osteoma Osteoide/patologia , Osteoma Osteoide/cirurgia , Adolescente , Biópsia por Agulha , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/patologia , Falanges dos Dedos da Mão/diagnóstico por imagem , Seguimentos , Humanos , Imuno-Histoquímica , Imageamento por Ressonância Magnética/métodos , Masculino , Osteoma Osteoide/diagnóstico por imagem , Polegar/patologia , Polegar/cirurgia , Resultado do TratamentoRESUMO
Human hemoglobin (HbA) transports molecular oxygen (O2) from the lung to tissues where the partial pressure of O2 is lower. O2 binds to HbA at the heme cofactor and is stabilized by a distal histidine (HisE7). HisE7 has been observed to occupy opened and closed conformations, and is postulated to act as a gate controlling the binding/release of O2. However, it has been suggested that HbA also contains intraprotein oxygen channels for entrances/exits far from the heme. In this study, we developed a novel method of crystal immersion in liquid oxygen prior to X-ray data collection. In the crystals immersed in liquid oxygen, the heme center was oxidized to generate aquomethemoglobin. Increases of structural flexibility were also observed in regions that are synonymous with previously postulated oxygen channels. These regions also correspond to medically relevant mutations which affect O2 affinity. The way HbA utilizes these O2 channels could have a profound impact on understanding the relationship of HbA O2 transport within these disease conditions. Finally, the liquid oxygen immersion technique can be utilized as a new tool to crystallographically examine proteins and protein complexes which utilize O2 for enzyme catalysis or transport.
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Cristalização/métodos , Hemoglobinas/química , Hemoglobinas/ultraestrutura , Simulação de Dinâmica Molecular , Oxigênio/química , Sítios de Ligação , Difusão , Porosidade , Ligação Proteica , Conformação ProteicaRESUMO
The threat from novel marine species introductions is a global issue. When non-native marine species are introduced to novel environments and become invasive, they can affect biodiversity, industry, ecosystem function, and both human and wildlife health. Isolated areas with sensitive or highly specialised endemic species can be particularly impacted. The global increase in the scope of tourism and other human activities, together with a rapidly changing climate, now put these remote ecosystems under threat. In this context, we analyse invasion pathways into South Georgia and the South Sandwich Islands (SGSSI) for marine non-native species via vessel biofouling. The SGSSI archipelago has high biodiversity and endemism, and has historically been highly isolated from the South American mainland. The islands sit just below the Polar Front temperature boundary, affording some protection against introductions. However, the region is now warming and SGSSI increasingly acts as a gateway port for vessel traffic into the wider Antarctic, amplifying invasion likelihood. We use remote Automatic Identification System vessel-tracking data over a 2-year period to map vessel movement and behaviour around South Georgia, and across the 'Scotia Sea', 'Magellanic' and northern 'Continental High Antarctic' ecoregions. We find multiple vessel types from locations across the globe frequently now enter shallow inshore waters and stop for prolonged periods (weeks/months) at anchor. Vessels are active throughout the year and stop at multiple port hubs, frequently crossing international waters and ecoregions. Management recommendations to reduce marine invasion likelihood within SGSSI include initiating benthic and hull monitoring at the identified activity/dispersion hubs of King Edward Point, Bay of Isles, Gold Harbour, St Andrews Bay and Stromness Bay. More broadly, regional collaboration and coordination is necessary at neighbouring international ports. Here vessels need increased pre- and post-arrival biosecurity assessment following set protocols, and improved monitoring of hulls for biofouling to pre-emptively mitigate this threat.
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The response of an electrolytic cell, in the shape of a slab, is analyzed in the framework of the Poisson-Nernst-Planck model in the limit of full dissociation. Two different types of boundary conditions on the electrodes are compared. One type describes the exchange of charges between the volume and the external circuit, in the form originally proposed by Chang and Jaffé and later extended to include specific adsorption, where the surface current density is proportional to the variation of the surface bulk density of ions with respect to the value of equilibrium. The other one describes the surface adsorption, in the limit of Langmuir. We show that in the simple case where the ions dissolved in the insulating liquid are identical in all the aspects, except for the sign of the charge, the two models are equivalent only if the phenomenological parameter entering the boundary condition of the Chang-Jaffé model, κ, is frequency dependent, and related to the adsorption coefficient, k(a), in the form κ = iωτ/(1 + iωτ)k(a), where τ is the desorption time and ω the circular frequency of the applied voltage, as proposed long ago by Macdonald.
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Mouse double minute 2 homolog (MDM2) is an E3 ubiquitin-protein ligase that is involved in the transfer of ubiquitin to p53 and other protein substrates. The expression of MDM2 is elevated in cancer cells and inhibitors of MDM2 showed potent anticancer activities. Many inhibitors target the p53 binding domain of MDM2. However, inhibitors such as Inulanolide A and MA242 are found to bind the RING domain of MDM2 to block ubiquitin transfer. In this report, crystal structures of MDM2 RING domain in complex with Inulanolide A and MA242 were solved. These inhibitors primarily bind in a hydrophobic site centered at the sidechain of Tyr489 at the C-terminus of MDM2 RING domain. The C-terminus of MDM2 RING domain, especially residue Tyr489, is required for ubiquitin discharge induced by MDM2. The binding of these inhibitors at Tyr489 may interrupt interactions between the MDM2 RING domain and the E2-Ubiquitin complex to inhibit ubiquitin transfer, regardless of what the substrate is. Our results suggest a new mechanism of inhibition of MDM2 E3 activity for a broad spectrum of substrates.
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Proteínas Proto-Oncogênicas c-mdm2 , Proteína Supressora de Tumor p53 , Animais , Camundongos , Ligação Proteica , Estrutura Terciária de Proteína , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Ubiquitina/química , Ubiquitina-Proteína Ligases/metabolismoRESUMO
The 2008 Disaster Mitigation Preparedness (DMP) study took place in Aceh province, Indonesia. It sought to help develop radio programmes and messages to increase resilience to disasters. The role of radio was evaluated during and after the 2004 Asian tsunami disaster. The study team interviewed 984 tsunami survivors from nine sub-districts of Banda Aceh, and local nongovernmental organisations convened eight focus groups around the area of Aceh Besar. Six key informant interviews were held with government disaster management agencies. The DMP survey is the first of its kind to interview a representative random sample of Banda Aceh residents. It reveals the importance of community and social networks, during disaster situations, when essential communications are down. A disaster warning information system based on a multi-media approach needs to be developed. The wider community should be involved in the planning, education and training of Banda Aceh and Aceh Besar residents to facilitate appropriate personal and community survival strategies.
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Defesa Civil/instrumentação , Serviços de Saúde Comunitária/métodos , Planejamento em Desastres/métodos , Rádio , Tsunamis , Ásia , Defesa Civil/métodos , Defesa Civil/organização & administração , Serviços de Saúde Comunitária/organização & administração , Planejamento em Desastres/organização & administração , Feminino , Grupos Focais , Pesquisas sobre Atenção à Saúde , Humanos , Indonésia , Masculino , Inquéritos e Questionários , Fatores de TempoRESUMO
COVID-19 can cause damage to the lung, which can result in progressive respiratory failure and potential death. Chest radiography and CT are the imaging tools used to diagnose and monitor patients with COVID-19. Lung ultrasound (LUS) during COVID-19 is being used in some areas to aid decision-making and improve patient care. However, its increased use could help improve existing practice for patients with suspected COVID-19, or other lung disease. A limitation of LUS is that it requires practitioners with sufficient competence to ensure timely, safe, and diagnostic clinical/imaging assessments. This commentary discusses the role and governance of LUS during and beyond the COVID-19 pandemic, and how increased education and training in this discipline can be undertaken given the restrictions in imaging highly infectious patients. The use of simulation, although numerical methods or dedicated scan trainers, and machine learning algorithms could further improve the accuracy of LUS, whilst helping to reduce its learning curve for greater uptake in clinical practice.
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COVID-19/diagnóstico por imagem , Pneumonia Viral/diagnóstico por imagem , Radiologia/educação , Ultrassonografia/métodos , Competência Clínica , Humanos , Aprendizado de Máquina , Pandemias , Pneumonia Viral/virologia , Sistemas Automatizados de Assistência Junto ao Leito , SARS-CoV-2RESUMO
Avascular necrosis of the metacarpal head, known as Dieterich disease, is rare. The underlying pathogenesis of the disease is not clearly understood, and there are few cases reported in the literature. Nonoperative treatment with rest and nonsteroidal anti-inflammatory drugs is often successful, but surgical management is sometimes indicated. The case outlined here describes a novel application of the known technique of metacarpophalangeal joint denervation to relieve pain while maintaining joint mechanics and grip strength.
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Osteonecrose , Denervação , Humanos , Articulação Metacarpofalângica/cirurgia , Metacarpo/anormalidades , Osteonecrose/cirurgiaRESUMO
Osteoarthritis in synovial joints remains a major cause of long-term disability worldwide, with symptoms produced by the progressive deterioration of the articular cartilage. The earliest cartilage changes are thought to be alteration in its main protein components, namely proteoglycan and collagen. Loss of proteoglycans bound in the collagen matrix which maintain hydration and stiffness of the structure is followed by collagen degradation and loss. The development of new treatments for early osteoarthritis is limited by the lack of accurate biomarkers to assess the loss of proteoglycan. One potential biomarker is magnetic resonance imaging (MRI). We present the results of a novel MRI methodology, Fast Field-Cycling (FFC), to assess changes in critical proteins by demonstrating clear quantifiable differences in signal from normal and osteoarthritic human cartilage for in vitro measurements. We further tested proteoglycan extracted cartilage and the key components individually. Three clear signals were identified, two of which are related predominantly to the collagen component of cartilage and the third, a unique very short-lived signal, is directly related to proteoglycan content; we have not seen this in any other tissue type. In addition, we present the first volunteer human scan from our whole-body FFC scanner where articular cartilage measurements are in keeping with those we have shown in tissue samples. This new clinical imaging modality offers the prospect of non-invasive monitoring of human cartilage in vivo and hence the assessment of potential treatments for osteoarthritis. Keywords: Fast Field-Cycling NMR; human hyaline cartilage; Osteoarthritis; T1 dispersion; quadrupolar peaks; protein interactions.
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Cartilagem Articular , Osteoartrite , Cartilagem Articular/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Osteoartrite/diagnóstico por imagem , ProteoglicanasRESUMO
Negative strand RNA viruses (NSVs) include many important human pathogens, such as influenza virus, Ebola virus, and rabies virus. One of the unique characteristics that NSVs share is the assembly of the nucleocapsid and its role in viral RNA synthesis. In NSVs, the single strand RNA genome is encapsidated in the linear nucleocapsid throughout the viral replication cycle. Subunits of the nucleocapsid protein are parallelly aligned along the RNA genome that is sandwiched between two domains composed of conserved helix motifs. The viral RNA-dependent-RNA polymerase (vRdRp) must recognize the protein-RNA complex of the nucleocapsid and unveil the protected genomic RNA in order to initiate viral RNA synthesis. In addition, vRdRp must continuously translocate along the protein-RNA complex during elongation in viral RNA synthesis. This unique mechanism of viral RNA synthesis suggests that the nucleocapsid may play a regulatory role during NSV replication.
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Vírus de RNA de Sentido Negativo/fisiologia , Vírus de RNA de Sentido Negativo/ultraestrutura , Proteínas do Nucleocapsídeo/química , Nucleocapsídeo/química , Nucleocapsídeo/fisiologia , Genoma Viral , Modelos Moleculares , Vírus de RNA de Sentido Negativo/química , Vírus de RNA de Sentido Negativo/genética , Nucleocapsídeo/genética , Nucleocapsídeo/ultraestrutura , Proteínas do Nucleocapsídeo/metabolismo , Conformação Proteica , Dobramento de Proteína , RNA Viral/biossíntese , RNA Viral/genética , RNA Viral/metabolismo , RNA Polimerase Dependente de RNA/metabolismoRESUMO
PURPOSE: Inflammation is central in disease pathophysiology and accurate methods for its detection and quantification are increasingly required to guide diagnosis and therapy. Here we explored the ability of Fast Field-Cycling Magnetic Resonance (FFC-MR) in quantifying the signal of ultra-small superparamagnetic iron oxide particles (USPIO) phagocytosed by J774 macrophage-like cells as a proof-of-principle. METHODS: Relaxation rates were measured in suspensions of J774 macrophage-like cells loaded with USPIO (0-200⯵g/ml Fe as ferumoxytol), using a 0.25â¯T FFC benchtop relaxometer and a human whole-body, in-house built 0.2â¯T FFC-MR prototype system with a custom test tube coil. Identical non-imaging, saturation recovery pulse sequence with 90° flip angle and 20 different evolution fields selected logarithmically between 80 µT and 0.2â¯T (3.4â¯kHz and 8.51â¯MHz proton Larmor frequency [PLF] respectively). Results were compared with imaging flow cytometry quantification of side scatter intensity and USPIO-occupied cell area. A reference colorimetric iron assay was used. RESULTS: The T1 dispersion curves derived from FFC-MR were excellent in detecting USPIO at all concentrations examined (0-200⯵g/ml Fe as ferumoxytol) vs. control cells, pâ¯≤â¯0.001. FFC-NMR was capable of reliably detecting cellular iron content as low as 1.12â¯ng/µg cell protein, validated using a colorimetric assay. FFC-MR was comparable to imaging flow cytometry quantification of side scatter intensity but superior to USPIO-occupied cell area, the latter being only sensitive at exposuresâ¯≥â¯10⯵g/ml USPIO. CONCLUSIONS: We demonstrated for the first time that FFC-MR is capable of quantitative assessment of intra-cellular iron which will have important implications for the use of USPIO in a variety of biological applications, including the study of inflammation.
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Óxido Ferroso-Férrico/química , Macrófagos/metabolismo , Imageamento por Ressonância Magnética/métodos , Colorimetria , Desenho de Equipamento , Citometria de Fluxo , Humanos , Técnicas In Vitro , Inflamação/metabolismo , Imageamento por Ressonância Magnética/instrumentação , Tamanho da Partícula , Fagocitose , Estudo de Prova de Conceito , SuspensõesRESUMO
A small, local-level communication initiative aimed to bring about social change and development in communities affected by sustained conflict in Mindanao, Philippines. A realist evaluation involved a secondary analysis of existing data sets that revealed previously undetected mechanisms and 13 outcomes for improving dialogue, livelihood, and participatory communication. This article describes the method developed for the realist evaluation and constructs Context-Mechanism-Outcome configurations from the existing data sets. The realist evaluation represents what took place in a context characterized by conflict, disadvantage and disempowerment through 2 key mechanisms, community-centered radio and community radio volunteers. Both mechanisms became voices for the voiceless. The community-centered radio program supported community volunteers to mobilize communities to participate in radio segments, offering opportunities for their voices to be heard on local issues resulting in discussion, provision of services not previously offered, community leaders more responsive to community needs, and coordinated community action that resolved needs.
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Participação da Comunidade , Comunicação em Saúde/métodos , Rádio , Planejamento Social , Conflitos Armados , Feminino , Humanos , Masculino , Filipinas , Avaliação de Programas e Projetos de Saúde , Mudança Social , Voluntários/estatística & dados numéricosRESUMO
INTRODUCTION: Phase II clinical trials including geriatric assessment (GA) measures are critical for improving the evidence base for older adults with cancer. We assessed the efficacy and tolerability of nab-paclitaxel in older adults with metastatic breast cancer (MBC). PATIENTS AND METHODS: Patients aged ≥ 65 years with MBC and ≤ 1 previous line of chemotherapy received 100 mg of nab-paclitaxel on days 1, 8, and 15 of a 28-day cycle. A GA was completed pre-chemotherapy, and the validated Cancer and Aging Research Group (CARG) chemotherapy toxicity risk score was calculated. Relationships between tolerability (number of courses, hospitalizations, dose reductions, and toxicity) and risk score were assessed using general linear models, Student t tests, and the Fisher test. Response rate and progression-free survival were evaluated using the Kaplan-Meier method. RESULTS: Forty patients (mean age, 73 years; range, 65-87 years) were included. The median number of cycles was 6, 75% (n = 30) of patients had ≥ 1 dose hold, and 50% (n = 20) had ≥ 1 dose reduction. Fifty-eight percent (n = 23) had treatment-related ≥ grade 3 toxicities, and 30% (n = 12) were hospitalized owing to toxicity. Thirty-five percent (n = 14) responded, and the median progression-free survival was 6.5 months (95% confidence interval, 5.5 months to undefined). Patients with intermediate/high toxicity risk scores had higher risk of grade ≥ 3 toxicity than those with low risk scores (odds ratio, 5.8; 95% confidence interval, 1.3-33.1; P = .01). A higher mean risk score was associated with higher likelihood of dose reductions and hospitalizations. CONCLUSIONS: Among older adults with MBC receiving weekly nab-paclitaxel, more than one-half experienced ≥ grade 3 chemotherapy toxicity. However, a GA-based risk score could predict treatment tolerability.
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Albuminas/uso terapêutico , Antineoplásicos Fitogênicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Paclitaxel/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Albuminas/administração & dosagem , Albuminas/toxicidade , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/toxicidade , Esquema de Medicação , Feminino , Avaliação Geriátrica , Humanos , Masculino , Metástase Neoplásica , Paclitaxel/administração & dosagem , Paclitaxel/toxicidade , Resultado do TratamentoRESUMO
When conventional methods of identification, such as visual recognition and dental comparison, cannot be used to identify a deceased person, it becomes necessary to consider alternative methods. The presence of an orthopedic implant in a body may assist identification if ante-mortem medical records are available for comparison. Another method of identification involves comparison of ante-mortem and postmortem radiographs. Eight cases are reported from Forensic Science SA where the presence of orthopedic implants and/or ante-mortem radiographs were used to try to establish identification. In six cases, positive identification was established, and in two cases with upper limb orthopedic implants, the bones remained unidentified. Manufacturers were unable to provide any information about the distribution and use of the implants that could be of use with identification, as there are no requirements in Australia for individual medical implants to be tracked. Such a system has the potential to aid postmortem identification if serial codes were etched onto implants that could then be traced to manufacturers, surgeons, and recipients of these devices.
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Antropologia Forense/métodos , Próteses e Implantes , Adulto , Idoso , Idoso de 80 Anos ou mais , Artroplastia de Quadril , Articulação do Cotovelo/diagnóstico por imagem , Feminino , Esporão do Calcâneo/diagnóstico por imagem , Esporão do Calcâneo/cirurgia , Articulação do Quadril/diagnóstico por imagem , Articulação do Quadril/cirurgia , Humanos , Fraturas do Úmero/diagnóstico por imagem , Fraturas do Úmero/cirurgia , Masculino , Radiografia , Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral/cirurgia , Fraturas da Ulna/diagnóstico por imagem , Fraturas da Ulna/cirurgiaAssuntos
Doenças dos Cavalos , Proteômica , Animais , Doenças dos Cavalos/diagnóstico , Cavalos , MetabolômicaRESUMO
Pulmonary research requires models that represent the physiology of alveolar epithelium but concerns with reproducibility, consistency and the technical and ethical challenges of using primary or stem cells has resulted in widespread use of continuous cancer or other immortalized cell lines. The A549 'alveolar' cell line has been available for over four decades but there is an inconsistent view as to its suitability as an appropriate model for primary alveolar type II (ATII) cells. Since most work with A549 cells involves short term culture of proliferating cells, we postulated that culture conditions that reduced proliferation of the cancer cells would promote a more differentiated ATII cell phenotype. We examined A549 cell growth in different media over long term culture and then used microarray analysis to investigate temporal regulation of pathways involved in cell cycle and ATII differentiation; we also made comparisons with gene expression in freshly isolated human ATII cells. Analyses indicated that long term culture in Ham's F12 resulted in substantial modulation of cell cycle genes to result in a quiescent population of cells with significant up-regulation of autophagic, differentiation and lipidogenic pathways. There were also increased numbers of up- and down-regulated genes shared with primary cells suggesting adoption of ATII characteristics and multilamellar body (MLB) development. Subsequent Oil Red-O staining and Transmission Electron Microscopy confirmed MLB expression in the differentiated A549 cells. This work defines a set of conditions for promoting ATII differentiation characteristics in A549 cells that may be advantageous for studies with this cell line.
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Células A549/fisiologia , Células Epiteliais Alveolares/fisiologia , Diferenciação Celular/fisiologia , Células A549/ultraestrutura , Células Epiteliais Alveolares/ultraestrutura , Técnicas de Cultura de Células , Ciclo Celular/fisiologia , Regulação da Expressão Gênica/fisiologia , Humanos , Microscopia Eletrônica de Transmissão , Análise de Sequência com Séries de Oligonucleotídeos , Fenótipo , Reação em Cadeia da PolimeraseRESUMO
We report the clinical and toxicological features of a case of fatal iodine ingestion, and summarize the physiology, clinical characteristics and management of iodine ingestion. Physicians are likely to have little experience in managing such patients, particularly with the advent of less toxic preparations, and therefore need ready access to management guidelines. This case also highlights the potential for substances to retain their toxicity over long periods of time.