Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 24
Filtrar
1.
J Adv Nurs ; 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38779925

RESUMO

AIM: To identify key factors that influence personal care workers' (PCW) intention to stay in residential aged care (RAC). BACKGROUND: PCWs are the 'backbone' of providing direct care in RAC settings. The well-being of older people hinges upon their dedication and commitment; thus, enhancing their intention to stay is a priority to reduce turnover and ensure continuity of care. METHODS: Six databases were searched for articles focusing on factors influencing PCWs' intention to stay in RAC. Studies were independently assessed for quality using the Joanna Briggs Institute Methodology for systematic review tools. Reporting of the results followed the PRISMA guidelines. FINDINGS: Eight articles published between 2010 and 2022 were included. The key issues were categorized as: (a) sociodemographic characteristics; (b) psychological factors; (c) workplace factors and (d) job satisfaction. Older age, being married and immigration status were positively associated with intention to stay. Work stress and burnout contributed towards demotivation, while a supportive and engaging organizational culture that recognized workers' contributions and provided appropriate remuneration and benefits, enhanced job satisfaction and retention. CONCLUSION: This review affirms the complexity of the decision-making process influencing workers' intention to stay. A comprehensive understanding of the interplay of these factors and the personal and sociocultural challenges faced by PCWs is essential to design strategies to provide support and enhance job satisfaction and retention. IMPLICATIONS FOR AGED CARE: This review showed that support from the organization is critical in improving PCWs' intention to stay in aged care. Given the interconnectedness of a range of key factors, decision-makers need to address modifiable factors holistically. Including PCWs in planning retention strategies could be the missing link in tailoring interventions towards workforce retention. IMPACT: Personal, psychological and workplace factors alone and in combination influence personal care workers' intention to stay in residential aged care (RAC). The interrelationships among the factors impacting PCWs' intention to stay are complex, wherein a change in one often influences other factors. Addressing the causes of psychological stress, improving workplace culture and understanding their interrelationships provide a foundation for co-designing strategies to promote intention to stay among PCWs in RAC. REPORTING METHOD: The authors have adhered to relevant EQUATOR guidelines PRISMA. NO PATIENT OR PUBLIC CONTRIBUTION: This integrative review is conducted with no involvement or contribution from patients or the public.

2.
Int J Nurs Stud ; 146: 104568, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37597458

RESUMO

BACKGROUND: Depression in older people living in residential aged care is a serious and highly prevalent health issue, with loneliness and social isolation being major contributors. The COVID-19 pandemic underscored the harm visiting restrictions have on the mental wellbeing of older people in residential aged care. However, there is a need to systematically review the relationship between family visits and depression in this population. OBJECTIVE: This literature review seeks to explore the association between family visits and depression among those living in residential aged care. METHODS: An integrative review was conducted in March 2022, based on a search of seven databases from inception to 2022. Papers were included if the studies were situated in a residential aged care facility and explored the impact of in-person family visits on depression of residents. Those that examined impact of family visits on community-dwelling older people and papers examining virtual family visits were excluded. The quality of the included papers was assessed using appropriate critical appraisal tools. Guided by the aim of this study, the included papers were narratively synthesised and presented thematically (PROSPERO ID CRD42022325895). RESULTS: Ten papers, published between 1991 and 2022, were included in the final synthesis. Multiple categorisations of frequency of visits and different scales were used to assess depression. Depression among residents in aged care facilities varied from 20 % to 58.7 % with 40 % of studies showing a positive association between the frequency of family visits and lower rate of depression. Three themes influencing the association between family visits and depression in residential aged care were identified. These were: (i) intersection of culture, filial values, and depression; (ii) resident-related factors including whether admission was voluntary and presence of functional impairment; and (iii) non-resident-related factors such as social activities for residents and staff involvement. CONCLUSION: Family visits ameliorated loneliness and depression among residents in aged care however, other factors such as culture, comorbidities and functional impairment, opportunities for socialisation and the social involvement of facility staff also influenced depression. Whilst the low number of studies reviewed limited comparison and generalisation of results, the review highlighted the broader and crucial role of healthcare staff in facilitating socialisation and promoting mental wellbeing of residents especially those who are not visited by families. TWEETABLE ABSTRACT: Family visits ameliorate depression in institutionalised older people but may not be the "silver bullet" as depression is multifactorial.


Assuntos
COVID-19 , Pandemias , Idoso , Humanos , Instituição de Longa Permanência para Idosos , Atenção à Saúde , Vida Independente
3.
Vis Comput Ind Biomed Art ; 6(1): 9, 2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-37198498

RESUMO

The large language model called ChatGPT has drawn extensively attention because of its human-like expression and reasoning abilities. In this study, we investigate the feasibility of using ChatGPT in experiments on translating radiology reports into plain language for patients and healthcare providers so that they are educated for improved healthcare. Radiology reports from 62 low-dose chest computed tomography lung cancer screening scans and 76 brain magnetic resonance imaging metastases screening scans were collected in the first half of February for this study. According to the evaluation by radiologists, ChatGPT can successfully translate radiology reports into plain language with an average score of 4.27 in the five-point system with 0.08 places of information missing and 0.07 places of misinformation. In terms of the suggestions provided by ChatGPT, they are generally relevant such as keeping following-up with doctors and closely monitoring any symptoms, and for about 37% of 138 cases in total ChatGPT offers specific suggestions based on findings in the report. ChatGPT also presents some randomness in its responses with occasionally over-simplified or neglected information, which can be mitigated using a more detailed prompt. Furthermore, ChatGPT results are compared with a newly released large model GPT-4, showing that GPT-4 can significantly improve the quality of translated reports. Our results show that it is feasible to utilize large language models in clinical education, and further efforts are needed to address limitations and maximize their potential.

4.
J Aerosol Med Pulm Drug Deliv ; 36(1): 20-26, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36594924

RESUMO

Introduction: The delivery of cell therapies may be an important frontier to treat different respiratory diseases in the near future. However, the cell size, delivery conditions, cell viability, and effect in the pulmonary function are critical factors. We performed a proof-of-concept experiment using ex vivo lungs and novel subglottic airway device that allows for selective lobar isolation and administration of drugs and biologics in liquid solution deep into the lung tissues, while simultaneously ventilating the rest of the lung lobes. Methods: We used radiolabeled cells and positron emission tomography-computed tomography (PET-CT) imaging to demonstrate the feasibility of high-yield cell delivery to a specifically targeted lobe. This study proposes an alternative delivery method of live cells labeled with radioactive isotope into the lung parenchyma and tracks the cell delivery using PET-CT imaging. The technique combines selective lobar isolation and lobar infusion to carry large particles distal to the trachea, subtending bronchial segments and reaching alveoli in targeted regions. Results: The solution with cells and carrier achieved a complete and homogeneous lobar distribution. An increase in tissue density was shown on the computed tomography (CT) scan, and the PET-CT imaging demonstrated retention of the activity at central, peripheral lung parenchyma, and pleural surface. The increase in CT density and metabolic activity of the isotope was restricted to the desired lobe only without leak to other lobes. Conclusion: The selective lobe delivery is targeted and imaging-guided by bronchoscopy and CT to a specific diseased lobe during mechanical ventilation. The feasibility of high-yield cell delivery demonstrated in this study will lead to the development of potential novel therapies that contribute to lung health.


Assuntos
Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Respiração Artificial , Administração por Inalação , Pulmão/diagnóstico por imagem , Células-Tronco
5.
Gerontologist ; 63(8): 1311-1319, 2023 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-35709945

RESUMO

BACKGROUND AND OBJECTIVES: The age-friendly university (AFU) initiative embodies the collaborative efforts of promoting age inclusivity and diversity in higher education, embracing lifelong learning and civic participation in older people. This scoping review aims to explore the conceptualization of AFU, the experiences, and the strategies used in operationalizing the AFU principles of participating universities in becoming members of the age-friendly university network. RESEARCH DESIGN AND METHODS: A search of peer-reviewed papers published from 2012 to July 2021, conducted in nine databases using JBI scoping review methodology, found 1,752 articles. Of these, 13 papers were eligible for inclusion. RESULTS: Three themes were identified as key to becoming an AFU: (a) interdisciplinary collaboration within the university; (b) strong partnership with the community; and (c) alignment with global priorities and initiatives. Furthermore, identifying barriers to physical access in universities, such as signage, walkways, and transportation, addressing the less tangible issues of ageism and promoting intergenerational learning were essential to promote engagement of older people. DISCUSSION AND IMPLICATIONS: This review underscores the need for a multidisciplinary approach within the university, the reciprocal benefits of authentic university-community collaborations, and the advantages of harnessing international resources and global influence to becoming an AFU. Although the principles of the AFU remain aspirational, the ideals championed by the pioneering universities in the AFU network brought the mutual benefits of intergenerational learning, the challenges and support required for older learners to the fore, propelling the AFU agenda forward.


Assuntos
Envelhecimento , Relação entre Gerações , Humanos , Idoso , Universidades , Participação da Comunidade , Conhecimento , Dinâmica Populacional
6.
AJR Am J Roentgenol ; 216(4): 1040-1045, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33566634

RESUMO

OBJECTIVE. We hypothesized that intravitreal silicone oil would show attenuation similar to that of fat on dual-energy CT 190-keV virtual monoenergetic images (VMIs) with high frequency and that this appearance would enable confident determination of the presence or absence of intravitreal silicone oil. The purpose of the present study was to test our hypothesis in a blinded multireader study of selected patients with and without intravitreal silicone oil as well as in an unblinded ROI-based assessment. MATERIALS AND METHODS. In this retrospective study of 50 dual-energy CT examinations of the head that included 100 globes (64 that were normal, 19 that exhibited hyperattenuating mimics, and 17 that contained silicone oil), three neuroradiologists independently assessed anonymized 190-keV VMIs for intravitreal attenuation similar to that of fat. Interobserver agreement was calculated. The mean attenuation value on weighted-average images and 190-keV VMIs was recorded. RESULTS. The three readers identified intravitreal attenuation values similar to that of fat in 100% of globes that contained silicone oil and 0% of globes that did not contain silicone oil (100% sensitivity, specificity, PPV, and accuracy) with 100% agreement. The mean attenuation value of silicone oil on 190-keV VMIs was -55 HU, which was significantly less than the mean attenuation on 190-keV VMIs of normal globes and hyperattenuating mimics (p < .001 for both). CONCLUSION. Intravitreal silicone oil shows attenuation of -60 to -49 HU on 190-keV VMIs. With the use of these images only, three neuroradiologists identified intravitreal silicone oil with 100% accuracy and perfect agreement.


Assuntos
Óleos de Silicone , Tomografia Computadorizada por Raios X/métodos , Corpo Vítreo/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Injeções Intravítreas , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Adulto Jovem
7.
J Gerontol A Biol Sci Med Sci ; 76(2): 277-285, 2021 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-32504466

RESUMO

BACKGROUND: Muscle metrics derived from computed tomography (CT) are associated with adverse health events in older persons, but obtaining these metrics using current methods is not practical for large datasets. We developed a fully automated method for muscle measurement on CT images. This study aimed to determine the relationship between muscle measurements on CT with survival in a large multicenter trial of older adults. METHOD: The relationship between baseline paraspinous skeletal muscle area (SMA) and skeletal muscle density (SMD) and survival over 6 years was determined in 6,803 men and 4,558 women (baseline age: 60-69 years) in the National Lung Screening Trial (NLST). The automated machine learning pipeline selected appropriate CT series, chose a single image at T12, and segmented left paraspinous muscle, recording cross-sectional area and density. Associations between SMA and SMD with all-cause mortality were determined using sex-stratified Cox proportional hazards models, adjusted for age, race, height, weight, pack-years of smoking, and presence of diabetes, chronic lung disease, cardiovascular disease, and cancer at enrollment. RESULTS: After a mean 6.44 ± 1.06 years of follow-up, 635 (9.33%) men and 265 (5.81%) women died. In men, higher SMA and SMD were associated with a lower risk of all-cause mortality, in fully adjusted models. A one-unit standard deviation increase was associated with a hazard ratio (HR) = 0.85 (95% confidence interval [CI] = 0.79, 0.91; p < .001) for SMA and HR = 0.91 (95% CI = 0.84, 0.98; p = .012) for SMD. In women, the associations did not reach significance. CONCLUSION: Higher paraspinous SMA and SMD, automatically derived from CT exams, were associated with better survival in a large multicenter cohort of community-dwelling older men.


Assuntos
Envelhecimento/patologia , Pulmão/diagnóstico por imagem , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/patologia , Idoso , Estudos de Coortes , Feminino , Humanos , Aprendizado de Máquina , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/estatística & dados numéricos
8.
Skeletal Radiol ; 50(1): 69-78, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32607805

RESUMO

OBJECTIVE: Lumbar spine MRI interpretations have high variability reducing utility for surgical planning. This study evaluated a convolutional neural network (CNN) framework that generates automated MRI grading for its ability to predict the level that was surgically decompressed. MATERIALS AND METHODS: Patients who had single-level decompression were retrospectively evaluated. Sagittal T2 images were processed by a CNN (SpineNet), which provided grading for the following: central canal stenosis, disc narrowing, disc degeneration, spondylolisthesis, upper/lower endplate morphologic changes, and upper/lower marrow changes. The grades were used to calculate an aggregate score. The variables and the aggregate score were analyzed for their ability to predict the surgical level. For each surgical level subgroup, the surgical level aggregate scores were compared with the non-surgical levels. RESULTS: A total of 141 patients met the inclusion criteria (82 women, 59 men; mean age 64 years; age range 28-89 years). SpineNet did not identify central canal stenosis in 32 patients. Of the remaining 109, 96 (88%) patients had a decompression at the level of greatest stenosis. The higher stenotic grade was present only at the surgical level in 82/96 (85%) patients. The level with the highest aggregate score matched the surgical level in 103/141 (73%) patients and was unique to the surgical level in 91/103 (88%) patients. Overall, the highest aggregate score identified the surgical level in 91/141 (65%) patients. The aggregate MRI score mean was significantly higher for the L3-S1 surgical levels. CONCLUSION: A previously developed CNN framework accurately predicts the level of microdecompression for degenerative spinal stenosis in most patients.


Assuntos
Estenose Espinal , Espondilolistese , Adulto , Idoso , Idoso de 80 Anos ou mais , Descompressão Cirúrgica , Feminino , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Estenose Espinal/diagnóstico por imagem , Estenose Espinal/cirurgia , Espondilolistese/cirurgia
9.
Traffic Inj Prev ; 20(sup2): S195-S197, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31674830

RESUMO

Objective: The objective of this study was to examine the prevalence of sarcopenia (low muscle mass) and osteosarcopenia (low bone density and muscle mass) in older motor vehicle crash (MVC) occupants and the relationship of these musculoskeletal conditions with age, sex, and injury.Methods: Sarcopenia and osteopenia was assessed from abdominal computed tomography (CT) scans of 61 seriously injured MVC occupants over age 50 in the Crash Injury Research and Engineering Network (CIREN) database.Results: The prevalence was 43% for sarcopenia, 25% for osteopenia, and 15% for osteosarcopenia in the CIREN occupants. The Injury Severity Score (ISS) was higher in those with only sarcopenia (mean ± SE = 22.4 ± 2.3), followed by those with osteosarcopenia (17.9 ± 2.4) and only osteopenia (12.8 ± 1.5). More total fractures were observed in occupants with sarcopenia alone (7.6 ± 1.5) or osteosarcopenia (7.0 ± 2.1) compared to nonsarcopenic occupants with osteopenia (4.0 ± 2.5).Conclusions: Sarcopenia and osteosarcopenia may be associated with more serious injuries and fractures in MVCs.


Assuntos
Acidentes de Trânsito/estatística & dados numéricos , Doenças Ósseas Metabólicas/epidemiologia , Fraturas Ósseas/epidemiologia , Escala de Gravidade do Ferimento , Sarcopenia/epidemiologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Bases de Dados Factuais , Feminino , Fraturas Ósseas/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Veículos Automotores , Prevalência , Fatores Sexuais , Tomografia Computadorizada por Raios X , Estados Unidos/epidemiologia
10.
Acad Radiol ; 26(12): 1686-1694, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31326311

RESUMO

RATIONALE AND OBJECTIVES: To develop and evaluate an automated machine learning (ML) algorithm for segmenting the paraspinous muscles on chest computed tomography (CT) scans to evaluate for presence of sarcopenia. MATERIALS AND METHODS: A convolutional neural network based on the U-Net architecture was trained to perform muscle segmentation on a dataset of 1875 single slice CT images and was tested on 209 CT images of participants in the National Lung Screening Trial. Low-dose, noncontrast CT examinations were obtained at 33 clinical sites, using scanners from four manufacturers. The study participants had a mean age of 71.6 years (range, 70-74 years). Ground truth was obtained by manually segmenting the left paraspinous muscle at the level of the T12 vertebra. Muscle cross-sectional area (CSA) and muscle attenuation (MA) were recorded. Comparison between the ML algorithm and ground truth measures of muscle CSA and MA were obtained using Dice similarity coefficients and Pearson correlations. RESULTS: Compared to ground truth segmentation, the ML algorithm achieved median (standard deviation) Dice scores of 0.94 (0.04) in the test set. Mean (SD) muscle CSA was 14.3 (3.6) cm2 for ground truth and 13.7 (3.5) cm2 for ML segmentation. Mean (SD) MA was 41.6 (7.6) Hounsfield units (HU) for ground truth and 43.5 (7.9) HU for ML segmentation. There was high correlation between ML algorithm and ground truth for muscle CSA (r2 = 0.86; p < 0.0001) and MA (r2 = 0.95; p < 0.0001). CONCLUSION: The ML algorithm for measurement of paraspinous muscles compared favorably to manual ground truth measurements in the NLST. The algorithm generalized well to a heterogeneous set of low-dose CT images and may be capable of automated quantification of muscle metrics to screen for sarcopenia on routine chest CT examinations.


Assuntos
Algoritmos , Aprendizado de Máquina , Músculos Paraespinais/diagnóstico por imagem , Sarcopenia/diagnóstico , Tomografia Computadorizada por Raios X/métodos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doses de Radiação
11.
Sci Rep ; 9(1): 1856, 2019 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-30755653

RESUMO

The early treatment and rapid closure of acute or chronic wounds is essential for normal healing and prevention of hypertrophic scarring. The use of split thickness autografts is often limited by the availability of a suitable area of healthy donor skin to harvest. Cellular and non-cellular biological skin-equivalents are commonly used as an alternative treatment option for these patients, however these treatments usually involve multiple surgical procedures and associated with high costs of production and repeated wound treatment. Here we describe a novel design and a proof-of-concept validation of a mobile skin bioprinting system that provides rapid on-site management of extensive wounds. Integrated imaging technology facilitated the precise delivery of either autologous or allogeneic dermal fibroblasts and epidermal keratinocytes directly into an injured area, replicating the layered skin structure. Excisional wounds bioprinted with layered autologous dermal fibroblasts and epidermal keratinocytes in a hydrogel carrier showed rapid wound closure, reduced contraction and accelerated re-epithelialization. These regenerated tissues had a dermal structure and composition similar to healthy skin, with extensive collagen deposition arranged in large, organized fibers, extensive mature vascular formation and proliferating keratinocytes.


Assuntos
Bioimpressão/métodos , Pele/citologia , Cicatrização , Animais , Proliferação de Células , Colágeno/química , Células Epidérmicas/citologia , Desenho de Equipamento , Feminino , Fibroblastos/citologia , Humanos , Hidrogéis/química , Queratinócitos/citologia , Camundongos , Camundongos Nus , Estudo de Prova de Conceito , Reepitelização , Pele Artificial , Suínos , Engenharia Tecidual/métodos
12.
J Gerontol A Biol Sci Med Sci ; 74(7): 1063-1069, 2019 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-30124775

RESUMO

BACKGROUND: Opportunistic assessment of sarcopenia on CT examinations is becoming increasingly common. This study aimed to determine relationships between CT-measured skeletal muscle size and attenuation with 1-year risk of mortality in older adults enrolled in a Medicare Shared Savings Program (MSSP). METHODS: Relationships between skeletal muscle metrics and all-cause mortality were determined in 436 participants (52% women, mean age 75 years) who had abdominopelvic CT examinations. On CT images, skeletal muscles were segmented at the level of L3 using two methods: (a) all muscles with a threshold of -29 to +150 Hounsfield units (HU), using a dedicated segmentation software, (b) left psoas muscle using a free-hand region of interest tool on a clinical workstation. Muscle cross-sectional area (CSA) and muscle attenuation were measured. Cox regression models were fit to determine the associations between muscle metrics and mortality, adjusting for age, sex, race, smoking status, cancer diagnosis, and Charlson comorbidity index. RESULTS: Within 1 year of follow-up, 20.6% (90/436) participants died. In the fully-adjusted model, higher muscle index and muscle attenuation were associated with lower risk of mortality. A one-unit standard deviation (SD) increase was associated with a HR = 0.69 (95% CI = 0.49, 0.96; p = .03) for total muscle index, HR = 0.67 (95% CI = 0.49, 0.90; p < .01) for psoas muscle index, HR = 0.54 (95% CI = 0.40, 0.74; p < .01) for total muscle attenuation, and HR = 0.79 (95% CI = 0.66, 0.95; p = .01) for psoas muscle attenuation. CONCLUSION: In older adults, higher skeletal muscle index and muscle attenuation on abdominopelvic CT examinations were associated with better survival, after adjusting for multiple risk factors.


Assuntos
Músculos Psoas , Sarcopenia , Tomografia Computadorizada por Raios X/métodos , Idoso , Feminino , Humanos , Masculino , Medicare/estatística & dados numéricos , Tamanho do Órgão , Valor Preditivo dos Testes , Prognóstico , Modelos de Riscos Proporcionais , Músculos Psoas/diagnóstico por imagem , Músculos Psoas/patologia , Radiografia Abdominal/métodos , Sarcopenia/diagnóstico , Sarcopenia/mortalidade , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Estados Unidos/epidemiologia
13.
Case Rep Crit Care ; 2017: 1951965, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28250995

RESUMO

Malignant catatonia (MC) is a life-threatening manifestation which can occur in the setting of an underlying neuropsychiatric syndrome or general medical illness and shares clinical and pathophysiological features and medical comorbidities with the Neuroleptic Malignant Syndrome (NMS). The subsequent diagnosis and definitive therapy of MC are typically delayed, which increases morbidity and mortality. We present two cases of MC and review recent literature of MC and NMS, illustrating factors which delay diagnosis and management. When clinical features suggest MC or NMS, we propose early critical care consultation and stabilization with collaborative psychiatric management.

14.
J Morphol ; 277(6): 766-75, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27027525

RESUMO

The morphology of the avian skeleton is often studied in the context of adaptations for powered flight. The effects of other evolutionary forces, such as sexual selection, on avian skeletal design are unclear, even though birds produce diverse behaviors that undoubtedly require a variety of osteological modifications. Here, we investigate this issue in a family of passerine birds called manakins (Pipridae), which have evolved physically unusual and elaborate courtship displays. We report that, in species within the genus Manacus, the shaft of the radius is heavily flattened and shows substantial solidification. Past work anecdotally notes this morphology and attributes it to the species' ability to hit their wings together above their heads to produce loud mechanical sonations. Our results show that this feature is unique to Manacus compared to the other species in our study, including a variety of taxa that produce other sonations through alternate wing mechanisms. At the same time, our data reveal striking similarities across species in total radius volume and solidification. Together, this suggests that supposedly adaptive alterations in radial morphology occur within a conserved framework of a set radius volume and solidness, which in turn is likely determined by natural selection. Further allometric analyses imply that the radius is less constrained by body size and the structural demands that underlie powered flight, compared to other forelimb bones that are mostly unmodified across taxa. These results are consistent with the idea that the radius is more susceptible to selective modification by sexual selection. Overall, this study provides some of the first insight into the osteological evolution of passerine birds, as well as the way in which opposing selective forces can shape skeletal design in these species. J. Morphol. 277:766-775, 2016. © 2016 Wiley Periodicals, Inc.


Assuntos
Adaptação Fisiológica , Comportamento Animal , Evolução Biológica , Corte , Passeriformes/anatomia & histologia , Rádio (Anatomia)/anatomia & histologia , Animais , Imageamento Tridimensional , Tamanho do Órgão , Análise de Regressão
15.
Methods ; 99: 99-111, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26546729

RESUMO

Magnetic Resonance Imaging (MRI) is a commonly used, non-invasive imaging technique that provides visualization of soft tissues with high spatial resolution. In both a research and clinical setting, the major challenge has been identifying a non-invasive and safe method for longitudinal tracking of delivered cells in vivo. The labeling and tracking of contrast agent labeled cells using MRI has the potential to fulfill this need. Contrast agents are often used to enhance the image contrast between the tissue of interest and surrounding tissues with MRI. The most commonly used MRI contrast agents contain Gd(III) ions. However, Gd(III) ions are highly toxic in their ionic form, as they tend to accumulate in the liver, spleen, kidney and bones and block calcium channels. Endohedral metallofullerenes such as trimetallic nitride endohedral metallofullerenes (Trimetasphere®) are one unique class of fullerene molecules where a Gd3N cluster is encapsulated inside a C80 carbon cage referred to as Gd3N@C80. These endohedral metallofullerenes have several advantages over small chelated Gd(III) complexes such as increased stability of the Gd(III) ion, minimal toxic effects, high solubility in water and high proton relativity. In this study, we describe the evaluation of gadolinium-based Trimetasphere® positive contrast agent for the ​in vitro labeling and in vivo tracking of human amniotic fluid-derived stem cells within lung tissue. In addition, we conducted a 'proof-of-concept' experiment demonstrating that this methodology can be used to track the homing of stem cells to injured lung tissue and provide longitudinal analysis of cell localization over an extended time course.


Assuntos
Meios de Contraste/química , Fulerenos/química , Lesão Pulmonar/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Lesões Experimentais por Radiação/diagnóstico por imagem , Transplante de Células-Tronco , Animais , Proliferação de Células , Sobrevivência Celular/efeitos dos fármacos , Rastreamento de Células , Células Cultivadas , Meios de Contraste/toxicidade , Fulerenos/toxicidade , Humanos , Limite de Detecção , Pulmão/patologia , Lesão Pulmonar/terapia , Imageamento por Ressonância Magnética , Metalocenos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos SCID , Imagens de Fantasmas , Lesões Experimentais por Radiação/terapia , Coloração e Rotulagem , Células-Tronco/fisiologia
16.
BMC Urol ; 15: 103, 2015 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-26463481

RESUMO

BACKGROUND: Restoration of normal bladder volume and function (i.e., bioequivalent bladder) are observed within 8 weeks of performing subtotal cystectomy (STC; removal of ~70 % of the bladder) in 12-week old rats. For analysis of bladder function in rodents, terminal urodynamic approaches are largely utilized. In the current study, we investigated the potential for Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) scans to noninvasively track restoration of structure and function following STC. METHODS: Twelve week old female Fisher F344 rats underwent STC and were scanned via CT and/or MRI 2, 4, 8, and 12 weeks post-STC, followed by urodynamic testing. After euthanasia, bladders were excised for histological processing. RESULTS: MRI scans demonstrated an initial decline followed by a time-dependent increase to normal bladder wall thickness (BWT) by 8 weeks post-STC. Masson's trichrome staining showed a lack of fibrosis post-STC, and also revealed that the percent of smooth muscle in the bladder wall at 2 and 4 weeks positively correlated with pre-operative baseline BWT. Moreover, increased BWT values before STC was predictive of improved bladder compliance at 2 and 4 weeks post-STC. Cystometric studies indicated that repeated MRI manipulation (i.e. bladder emptying) apparently had a negative impact on bladder capacity and compliance. A "window" of bladder volumes was identified 2 weeks post-STC via CT scanning that were commensurate with normal micturition pressures measured in the same animal 6 weeks later. CONCLUSIONS: Taken together, the data indicate some limitations of "non-invasive" imaging to provide insight into bladder regeneration. Specifically, mechanical manipulation of the bladder during MRI appears to negatively impact the regenerative process per se, which highlights the importance of terminal cystometric studies.


Assuntos
Cistectomia/métodos , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X/métodos , Bexiga Urinária/fisiologia , Bexiga Urinária/cirurgia , Animais , Estudos de Viabilidade , Feminino , Masculino , Ratos , Ratos Endogâmicos F344 , Regeneração/fisiologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Cirurgia Assistida por Computador/métodos , Bexiga Urinária/anatomia & histologia
17.
Biomed Sci Instrum ; 51: 159-64, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25996713

RESUMO

Medical image data used for the development of computational human body models are often retrospectively acquired, and researchers are unlikely to encounter scans of healthy individuals in specific postures. We prospectively acquired scans in both prone and supine postures from 22 healthy young adults; M:F 1:1, with age, height, and weight of 28.8±7.0 years, 173.0±7.8 cm, and 70.6±10.9 kg. While prone, subjects’ arms were superior to the head and supported by a foam insert at axilla. Breath held, T1-weighted MRI scans were acquired using a Siemen’s Skyra 3T with an in-plane resolution of 1.56 mm (TR: 4.10 ms, TE: 1.23 ms, thickness: 2 mm, matrix: 256x256, FOV: 400 mm). Gross thoraco-abdominal compression was considered as the change in perpendicular distance in the transverse plane measured from the anterior margin of L4/L5 to the table (for prone) or exterior body surface (for supine). Gross thoraco-abdominal, liver and spleen compression were found to be 8.5% (71.6±12.9 mm prone vs. 78.7±12.4 mm supine; p=0.0013), 17.7% (110.4±4.1 mm prone vs. 134.8±2.6 mm supine; p<0.0001), and 3.5% (53.8±1.9 mm prone vs. 57.3±2.9 mm supine) respectively. Gender and spleen compression differences were not noted. The liver and spleen migrated on average 8.3 mm posteriorly, 11.4 mm rightward, 15.1 mm superiorly and 4.1 mm anteriorly, 6.1 mm rightward, 1.7 mm superiorly respectively. The data obtained from this set may be of use in computational biomechanics, surgical simulation, and medical device design.

18.
Urology ; 83(4): 930-8, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24485996

RESUMO

OBJECTIVE: To test if virtual endoscopy (VE) enabled by 3-dimensional computed tomographic (CT) scanner with supporting software allows for practical clinical interrogation and evaluation of the urethral lumen and anatomy in an animal model. METHODS: Assessment of urethral anatomy and repair results was performed in 18 male beagles using conventional retrograde urethrography, CT-assisted retrograde urethography, and voiding urethrocystography. The image slices from these studies were processed using TeraRecon software to create a virtual representation of the urethra and compared with conventional urethrography and postmortem analysis of retrieved urethras for diagnostic assessment and correlation. RESULTS: CT-assisted VE showed the orientation, size, and gross morphology of urethral anatomy, including the lesions in all the 18 animals studied. The VE showed patent urethra in 12 dogs, stenosed urethra in 3 dogs, urethral diverticulum with stricture in 2 animals, and fistula in one. These findings correlated with those of conventional diagnostic methods. The findings of the voiding and retrograde virtual urethrocystoscopy studies were also comparable. CONCLUSION: These results demonstrate that CT-assisted VE is able to identify the anatomic landmarks in an animal model. This allows for detection of the site of different pathologies and their relations to important structures such as urethral sphincters and the bladder neck. Digital imaging might be used to identify urethral pathologies with greater details and characterization of the lesions when compared with the conventional urethrocystography.


Assuntos
Cistoscopia/métodos , Endoscopia/métodos , Tomografia Computadorizada por Raios X/métodos , Uretra/diagnóstico por imagem , Doenças Uretrais/diagnóstico , Animais , Cães , Imageamento Tridimensional , Masculino , Modelos Animais , Software , Uretra/cirurgia , Doenças Uretrais/diagnóstico por imagem , Doenças Uretrais/patologia , Estreitamento Uretral/diagnóstico por imagem , Estreitamento Uretral/cirurgia , Bexiga Urinária/patologia , Bexiga Urinária/cirurgia , Micção
19.
Arthroscopy ; 27(7): 1005-13, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21498032

RESUMO

Femoroacetabular impingement has recently become a recognized cause of disability and hip arthritis. Hip arthroscopy and femoroacetabular reshaping have been performed to treat this condition. Quantification of the excess femoral and acetabular bone requiring resection has been challenging with the less invasive arthroscopic technique. We describe the use of intraoperative computed tomography assessing osteochondroplasty during arthroscopic surgery to treat cam- and pincer-type femoroacetabular impingement. We also describe the technical steps and present the important radiologic findings we have been able to visualize. We found intraoperative computed tomography scanning to be a reliable and reproducible method of assessing the quality of femoroacetabular impingement surgery. We believe that femoroacetabular impingement surgery can be assessed intraoperatively by use of computed tomography scanning where corrections can be made if necessary.


Assuntos
Artroscopia , Impacto Femoroacetabular/diagnóstico por imagem , Impacto Femoroacetabular/cirurgia , Cuidados Intraoperatórios , Cirurgia Assistida por Computador , Tomografia Computadorizada por Raios X , Adolescente , Feminino , Humanos , Cuidados Intraoperatórios/normas , Reprodutibilidade dos Testes , Tomografia Computadorizada por Raios X/normas , Adulto Jovem
20.
J Bone Joint Surg Am ; 92(15): 2583-8, 2010 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-21048177

RESUMO

BACKGROUND: Shoulder deformities are common secondary sequelae associated with brachial plexus birth palsy. The aim of the present study was to characterize three-dimensional glenohumeral deformity associated with brachial plexus birth palsy with use of microcomputed tomography scanning in a recently developed animal model. METHODS: Brachial plexus birth palsy was produced by a right-sided neurotomy of the C5 and C6 nerve roots in seven five-day-old Sprague-Dawley rats. Microcomputed tomography scanning was performed when the rats were four months of age. Glenoid size, version, and inclination; humeral head size; and acromion-glenoid distance were measured. Normal shoulders of age-matched rats (n = 9) served as controls. Statistical analysis was performed with use of the unpaired two-tailed Student t test. RESULTS: There were significant increases in glenoid retroversion (-7.6° ± 4.9° compared with 3.6° ± 2.1°; p = 0.038) and glenoid inclination (38.7° ± 7.3° compared with 11.2° ± 1.9°; p = 0.015) in the shoulders with simulated brachial plexus birth palsy in comparison with the normal, control shoulders. The glenohumeral joints were more medialized in the joints with simulated brachial plexus birth palsy as reflected by the acromion-glenoid distance measurement; however, the difference was not significant (3.20 ± 0.51 compared with 2.40 ± 0.18 mm; p = 0.12). Although the mean humeral head height and width measurements, on the average, were smaller in the brachial plexus birth palsy shoulders as compared with the normal, control shoulders, only the measurement of humeral head height was significantly different between the two groups (4.25 ± 2.02 compared with 4.97 ± 0.11 mm [p = 0.008] and 3.56 ± 0.27 compared with 4.19 ± 0.17 mm [p = 0.056], respectively). CONCLUSIONS: In this animal model, rats with simulated brachial plexus birth palsy developed gross architectural joint distortion characterized by increased glenoid retroversion and inclination. In addition, humeral heads tended to be smaller four months after simulated brachial plexus birth palsy.


Assuntos
Traumatismos do Nascimento/diagnóstico por imagem , Neuropatias do Plexo Braquial/diagnóstico por imagem , Deformidades Articulares Adquiridas/diagnóstico por imagem , Lesões do Ombro , Articulação do Ombro/diagnóstico por imagem , Microtomografia por Raio-X , Animais , Animais Recém-Nascidos , Traumatismos do Nascimento/fisiopatologia , Neuropatias do Plexo Braquial/fisiopatologia , Modelos Animais de Doenças , Deformidades Articulares Adquiridas/fisiopatologia , Masculino , Ratos , Ratos Sprague-Dawley
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...