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1.
J Telemed Telecare ; : 1357633X231194381, 2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37615156

RESUMO

Although the use of audiovisual telemedicine has grown in recent years especially during recent COVID-19-related lockdowns, evidence shows there is still a lack of tools that can be used for the assessment of telemedicine encounters. The few validated questionnaires that are available for assessing telemedicine encounters are not often used. Non-validated questionnaires dominate research, leading to results that cannot be compared or extrapolated to other research or medical sites. Development of standard measures for the assessment of telemedicine encounters has been advocated by stakeholders. The objective of this study is to provide a comprehensive set of measures by developing a conceptual approach and a preliminary Telemedicine Assessment Toolkit (TAT) for the assessment of audiovisual telemedicine encounters. A two-step conceptual approach was used to identify potential domains and sub-domains by qualitative analysis of a pool of questions from studies published from 2016 to 2021. Questions were adopted from validated questionnaires or generated to represent the underlying concept of each sub-domain, resulting in a core block of comprehensive questions. A toolkit is proposed with question-measures that cover the sub-domains relevant to the assessment of telemedicine encounters. This study recommended 11 domains to be used for the assessment of telemedicine encounters: "usability," "patient satisfaction," "patient-provider interaction," "patient perspectives," "telemedicine readiness," "qualitative feedback," "comparison to standard (in-person) care," "privacy," "technology," "patient feeling," and "patient costs." Of the 11 domains, 26 underlying sub-domains were created. From the subdomains, a 30-question core block was proposed. The core-block together with a precursor block aimed to retrieve demographic/patient characteristics and, together with a customizable clinical outcomes block, complete the comprehensive toolkit. The toolkit, upon testing and validation, would enable researchers and system owners to assess patient-oriented aspects of audiovisual telemedicine encounters more accurately and accelerate the adoption of common audiovisual telemedicine assessment measures.

2.
J Telemed Telecare ; : 1357633X231166161, 2023 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-37032470

RESUMO

INTRODUCTION: Telemedicine is the exchange of medical information from one site to another via electronic communications with the goal of improving a patient's clinical health status. Prior studies have identified the absence of a standardized assessment tool for evaluating telemedicine encounters. This study aims to collect and to analyze questionnaires used for the assessment of audiovisual telemedicine encounters from a patient perspective and aims to identify reasons driving the use of self-developed questionnaires. METHODS: We conducted a systematic search in PubMed for studies that used survey questionnaires to assess synchronous audiovisual telemedicine encounters from 2016 to 2021. We categorized questionnaires used into validated and non-validated types, and for each of them, collected questions, response format, author, year, specialty, and country of publication. RESULTS AND DISCUSSION: We analyzed a total of 71 articles. We found that only 16 studies used three validated questionnaires. The remaining 55 studies used non-validated questionnaires. Non-validated questionnaires had a high variability in length and used Likert scales, binary responses, multiple choice, and open-ended answers. We found only eight studies in which the authors gave a reason for resorting to designing their own questionnaires. This review reveals insufficient standardized survey questionnaires to be used for the assessment of audiovisual telemedicine encounters. Future research initiatives should focus on developing a standardized and validated instrument well accepted by researchers.

3.
Biomater Adv ; 148: 213355, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36893487

RESUMO

Visceral myopathy (VSCM) is a rare genetic disease, orphan of pharmacological therapy. VSCM diagnosis is not always straightforward due to symptomatology similarities with mitochondrial or neuronal forms of intestinal pseudo-obstruction. The most prevalent form of VSCM is associates with variants in the gene ACTG2, encoding the protein gamma-2 actin. Overall, VSCM is a mechano-biological disorder, in which different genetic variants lead to similar alterations to the contractile phenotype of enteric smooth muscles, resulting in the emergence of life-threatening symptoms. In this work we analyzed the morpho-mechanical phenotype of human dermal fibroblasts from patients affected with VSCM, demonstrating that they retain a clear signature of the disease when compared with different controls. We evaluated several biophysical traits of fibroblasts, and we show that a measure of cellular traction forces can be used as a non-specific biomarker of the disease. We propose that a simple assay based on traction forces could be designed to provide a valuable support for clinical decision or pre-clinical research.


Assuntos
Pseudo-Obstrução Intestinal , Humanos , Pseudo-Obstrução Intestinal/diagnóstico , Pseudo-Obstrução Intestinal/genética , Pseudo-Obstrução Intestinal/metabolismo , Actinas/genética , Actinas/metabolismo , Contração Muscular , Fenótipo , Músculo Liso/metabolismo
4.
Int J Technol Assess Health Care ; 38(1): e2, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34924067

RESUMO

INTRODUCTION: The use of telemedicine has broadened as technology that both restores continuity of care during disruptions in healthcare delivery and routinely provides primary care alone or in combination with in-person care. During the Covid-19 outbreak, the use of telemedicine as a routine care modality further accelerated. METHODS: A review of scientific studies that used telemedicine to provide care from December 2019 to December 2020 is presented. From an initial set of 2,191 articles, 36 studies are analyzed. Evidence is organized and evaluated according to the country of study, the clinical specialty, the technology platform used, and satisfaction and utilization outcomes. RESULTS: Thirty-one studies reported high patient satisfaction scores. Eight studies reported satisfaction from both providers and patients with no uniformly accepted assessment instrument. Eight studies conducted a descriptive analysis of telemedicine use and patient adoption patterns. Less than one-third of studies were controlled before/after studies. Most studies were conducted in the USA followed by Europe. CONCLUSIONS: Reported satisfaction rates are high, consistent with previously documented research, whereas utilization rates increased significantly compared with the prepandemic period. Future work in developing standardized uniform assessment instruments, embedded with each telemedicine system, would increase versatility and agility in the assessment, boosting statistical power and the interpretation of results.


Assuntos
COVID-19 , Telemedicina , Humanos , Pandemias , Satisfação Pessoal , SARS-CoV-2
5.
J Acoust Soc Am ; 147(6): 3795, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32611157

RESUMO

Anthropogenic activities are causing increased noise levels in the marine environment. To date, few studies have been undertaken to investigate the effects of different noise frequencies on the behaviour of juvenile fish. In this study, the behavioural changes of juvenile gilthead seabream (Sparus aurata) are evaluated when exposed to white noise filtered in third-octave bands centred at 63, 125, 500, and 1000 Hz (sound pressure level, 140-150 dB re 1 µΡa) for 7 h. The group dispersion, motility, and swimming height of the fish were analysed before and during the acoustic emission. Dispersion of the fish was found to reduce immediately upon application of low frequency sound (63 and 125 Hz) with a return to control condition after 2 h (indicative of habituation), whereas at 1 kHz, dispersion increased after 2 h without any habituation. The motility decreased significantly at 63 Hz throughout the 7 h of sound exposure. The swimming height decreased significantly for all frequencies other than 125 Hz. The results of this study highlight significant variations in the behavioural responses of juvenile fish that could have consequences on their fitness and survival.


Assuntos
Dourada , Acústica , Animais , Ruído/efeitos adversos , Som , Natação
6.
J Allied Health ; 49(1): 45-52, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32128538

RESUMO

Allied health professionals spend a considerable amount of time listening to and communicating with patients while providing care. The inclusion of appropriate communication skills as a part of the core curriculum for allied health professions is crucial. Metaphorical representations are used by both patients and healthcare providers when communicating. Patients express their symptoms using metaphors and health professionals may use metaphors to facilitate the provider-patient interaction. It is reasonable to expect that allied health faculty would intentionally train their students in the use of metaphor. However, research on knowledge, use, and perception of metaphors among allied health faculty is absent. To address the gap, our study, by using a 13-question online anonymous survey, aimed to: 1) assess how well faculty of nutrition, respiratory therapy, athletic training, and occupational therapy programs recognize metaphors, and 2) determine if faculty use metaphors when they have to explain a clinical concept. A total of 366 participants completed the survey. Participants agreed on the value of metaphorical communication and showed a willingness to use metaphors in educational settings to teach a clinical concept. Participants were often not able to correctly identify metaphors when used in sentences.


Assuntos
Pessoal Técnico de Saúde/educação , Docentes , Metáfora , Ensino , Adulto , Idoso , Estudos Transversais , Currículo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários
7.
Artigo em Inglês | MEDLINE | ID: mdl-31923630

RESUMO

Marine life is extremely sensitive to the effects of environmental noise due to its reliance on underwater sounds for basic life functions, such as searching for food and mating. However, the effects on invertebrate species are not yet fully understood. The aim of this study was to determine the biochemical responses of Arbacia lixula exposed to high-frequency noise. Protein concentration, enzyme activity (esterase, phosphatase and peroxidase) and cytotoxicity in coelomic fluid were compared in individuals exposed for three hours to consecutive linear sweeps of 100 to 200 kHz lasting 1 s, and control specimens. Sound pressure levels ranged between 145 and 160 dB re 1µPa. Coelomic fluid was extracted and the gene and protein expression of HSP70 with RT-PCR was evaluated on coelomocytes. A significant change was found in enzyme activity and in the expression of the HSP70 gene and protein compared to the control. These results suggested that high-frequency stimuli elicit a noise-induced physiological stress response in A. lixula, confirming the vulnerability of this species to acoustic exposure. Furthermore, these findings provide the first evidence that cell-free coelomic fluid can be used as a signal to evaluate noise exposure in marine invertebrates.


Assuntos
Arbacia/fisiologia , Líquidos Corporais/metabolismo , Proliferação de Células , Coelomomyces/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Hemólise , Ruído , Fosfatase Alcalina/metabolismo , Animais , Líquidos Corporais/química , Esterases/metabolismo , Proteínas de Choque Térmico HSP70/genética , Homeostase , Metaboloma , Peroxidase/metabolismo
8.
Sci Rep ; 8(1): 5333, 2018 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-29593247

RESUMO

Purpose of this study was the development of a 3D material to be used as substrate for breast cancer cell culture. We developed composite gels constituted by different concentrations of Alginate (A) and Matrigel (M) to obtain a structurally stable-in-time and biologically active substrate. Human aggressive breast cancer cells (i.e. MDA-MB-231) were cultured within the gels. Known the link between cell morphology and malignancy, cells were morphologically characterized and their invasiveness correlated through an innovative bioreactor-based invasion assay. A particular type of gel (i.e. 50% Alginate, 50% Matrigel) emerged thanks to a series of significant results: 1. cells exhibited peculiar cytoskeleton shapes and nuclear fragmentation characteristic of their malignancy; 2. cells expressed the formation of the so-called invadopodia, actin-based protrusion of the plasma membrane through which cells anchor to the extracellular matrix; 3. cells were able to migrate through the gels and attach to an engineered membrane mimicking the vascular walls hosted within bioreactor, providing a completely new 3D in vitro model of the very precursor steps of metastasis.


Assuntos
Alginatos , Neoplasias da Mama/patologia , Técnicas de Cultura de Células , Colágeno , Hidrogéis , Laminina , Proteoglicanas , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Sobrevivência Celular , Citoesqueleto/metabolismo , Combinação de Medicamentos , Feminino , Humanos , Fenômenos Mecânicos , Invasividade Neoplásica
9.
Sci Rep ; 6: 35367, 2016 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-27734939

RESUMO

Three-dimensional (3D) cell cultures represent fundamental tools for the comprehension of cellular phenomena both in normal and in pathological conditions. In particular, mechanical and chemical stimuli play a relevant role on cell fate, cancer onset and malignant evolution. Here, we use mechanically-tuned alginate hydrogels to study the role of substrate elasticity on breast adenocarcinoma cell activity. The hydrogel elastic modulus (E) was measured via atomic force microscopy (AFM) and a remarkable range (150-4000 kPa) was obtained. A breast cancer cell line, MCF-7, was seeded within the 3D gels, on standard Petri and alginate-coated dishes (2D controls). Cells showed dramatic morphological differences when cultured in 3D versus 2D, exhibiting a flat shape in both 2D conditions, while maintaining a circular, spheroid-organized (cluster) conformation within the gels, similar to those in vivo. Moreover, we observed a strict correlation between cell viability and substrate elasticity; in particular, the number of MCF-7 cells decreased constantly with increasing hydrogel elasticity. Remarkably, the highest cellular proliferation rate, associated with the formation of cell clusters, occurred at two weeks only in the softest hydrogels (E = 150-200 kPa), highlighting the need to adopt more realistic and a priori defined models for in vitro cancer studies.


Assuntos
Adenocarcinoma/patologia , Neoplasias da Mama/patologia , Técnicas de Cultura de Células , Microambiente Tumoral , Alginatos/química , Diferenciação Celular , Linhagem Celular Tumoral , Linhagem da Célula , Proliferação de Células , Sobrevivência Celular , Análise por Conglomerados , Módulo de Elasticidade , Elasticidade , Feminino , Citometria de Fluxo , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Humanos , Hidrogéis/química , Técnicas In Vitro , Células MCF-7 , Microscopia de Força Atômica , Pressão , Engenharia Tecidual/métodos
10.
BMC Bioinformatics ; 11: 566, 2010 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-21087464

RESUMO

BACKGROUND: Tissue MicroArray technology aims to perform immunohistochemical staining on hundreds of different tissue samples simultaneously. It allows faster analysis, considerably reducing costs incurred in staining. A time consuming phase of the methodology is the selection of tissue areas within paraffin blocks: no utilities have been developed for the identification of areas to be punched from the donor block and assembled in the recipient block. RESULTS: The presented work supports, in the specific case of a primary subtype of breast cancer (tubular breast cancer), the semi-automatic discrimination and localization between normal and pathological regions within the tissues. The diagnosis is performed by analysing specific morphological features of the sample such as the absence of a double layer of cells around the lumen and the decay of a regular glands-and-lobules structure. These features are analysed using an algorithm which performs the extraction of morphological parameters from images and compares them to experimentally validated threshold values. Results are satisfactory since in most of the cases the automatic diagnosis matches the response of the pathologists. In particular, on a total of 1296 sub-images showing normal and pathological areas of breast specimens, algorithm accuracy, sensitivity and specificity are respectively 89%, 84% and 94%. CONCLUSIONS: The proposed work is a first attempt to demonstrate that automation in the Tissue MicroArray field is feasible and it can represent an important tool for scientists to cope with this high-throughput technique.


Assuntos
Adenocarcinoma/patologia , Neoplasias da Mama/patologia , Análise Serial de Tecidos/métodos , Feminino , Humanos , Projetos Piloto
11.
Aquat Toxicol ; 85(1): 67-75, 2007 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-17875329

RESUMO

The effect of euplotin C -- a lipophilic bioactive metabolite produced by the ciliate Euplotes crassus -- on the kinetics of both phagocytosis of latex particles and fluid-phase uptake of dextran, was studied in the single-cell ciliate Paramecium primaurelia. The inhibition of food vacuole formation was concentration- and time-dependent (p<0.001), even if euplotin C did not completely block the phagocytosis. Following a 15 min treatment with a euplotin C (0.5 microg/ml), the latex particle uptake was inhibited up to 25%. Furthermore, the pretreatment of cells with taxol strongly counteracted euplotin C effect. The amount of extracellularly provided dextran, which is internalized exclusively by fluid-phase uptake, was quantified in cells whose phagocytic activity was blocked by trifluoperazine. The amount of the internalized dextran was about 50% of that in controls after 15 min incubation in the presence of euplotin C. Fluorescence confocal images showed that no endosomes were formed on the surface of these cells. The effect of euplotin C on the food vacuole formation and fluid-phase endocytosis is apparently mediated by a modification of microtubule network.


Assuntos
Endocitose/efeitos dos fármacos , Paramecium/efeitos dos fármacos , Sesquiterpenos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Anticorpos/análise , Anticorpos/metabolismo , Dextranos/metabolismo , Látex/metabolismo , Microtúbulos/efeitos dos fármacos , Paclitaxel/farmacologia , Paramecium/fisiologia , Fagocitose/efeitos dos fármacos , Sesquiterpenos/química , Fatores de Tempo , Trifluoperazina , Moduladores de Tubulina/farmacologia , Vacúolos/efeitos dos fármacos
12.
Cell Tissue Res ; 329(1): 187-96, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17429697

RESUMO

The aim of this study has been the biochemical demonstration of the presence of gamma-aminobutyric acid (GABA) in the Mediterranean sea fan Eunicella cavolini by means of high-performance liquid chromatography, and the description of the distribution pattern of GABA and its related molecules, glutamic acid decarboxylase (GAD), vesicular GABA transporter (VGAT) and one of the GABA receptors (GABA(B) R) by immunohistochemical methods. The interrelationships of GABA, GAD and GABA receptor immunoreactivity have been established by using double-immunohistochemical methods and confocal microscopy. The immunodetection of monoclonal and/or polyclonal antibodies has revealed GABA immunoreactivity throughout the polyp tissue, both in neuronal and non-neuronal elements. GAD immunoreactivity has been mostly localized in the neuronal compartment, contacting epithelial and muscular elements. GABA(B) R immunoreactivity appears particularly intense in the nematocytes and in the oocyte envelope; its presence in GAD-immunoreactive neurons in the tentacles suggests an autocrine type of regulation. Western blot analysis has confirmed that a GABA(B) R, with a molecular weight of 142 kDa, similar to that of rat brain, is present in E. cavolini polyp tissue. The identification of the sites of the synthesis, vesicular transport, storage and reception of GABA strongly suggests the presence of an almost complete set of GABA-related molecules for the functioning of the GABAergic system in this simple nervous system. The distribution of these different immunoreactivities has allowed us to hypothesize GABA involvement in nematocyst discharge, in body wall and enteric muscular contraction, in neuronal integration and in male gametocyte differentiation.


Assuntos
Cnidários/metabolismo , Proteínas da Membrana Plasmática de Transporte de GABA/metabolismo , Glutamato Descarboxilase/metabolismo , Receptores de GABA-B/metabolismo , Ácido gama-Aminobutírico/metabolismo , Animais , Cnidários/química , Cnidários/citologia , Feminino , Proteínas da Membrana Plasmática de Transporte de GABA/química , Proteínas da Membrana Plasmática de Transporte de GABA/isolamento & purificação , Glutamato Descarboxilase/química , Glutamato Descarboxilase/isolamento & purificação , Masculino , Especificidade de Órgãos/fisiologia , Ratos , Receptores de GABA-B/química , Receptores de GABA-B/isolamento & purificação , Ácido gama-Aminobutírico/química , Ácido gama-Aminobutírico/isolamento & purificação
13.
BMC Bioinformatics ; 8 Suppl 1: S18, 2007 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-17430562

RESUMO

BACKGROUND: The SYMBIOmatics Specific Support Action (SSA) is "an information gathering and dissemination activity" that seeks "to identify synergies between the bioinformatics and the medical informatics" domain to improve collaborative progress between both domains (ref. to http://www.symbiomatics.org). As part of the project experts in both research fields will be identified and approached through a survey. To provide input to the survey, the scientific literature was analysed to extract topics relevant to both medical informatics and bioinformatics. RESULTS: This paper presents results of a systematic analysis of the scientific literature from medical informatics research and bioinformatics research. In the analysis pairs of words (bigrams) from the leading bioinformatics and medical informatics journals have been used as indication of existing and emerging technologies and topics over the period 2000-2005 ("recent") and 1990-1990 ("past"). We identified emerging topics that were equally important to bioinformatics and medical informatics in recent years such as microarray experiments, ontologies, open source, text mining and support vector machines. Emerging topics that evolved only in bioinformatics were system biology, protein interaction networks and statistical methods for microarray analyses, whereas emerging topics in medical informatics were grid technology and tissue microarrays. CONCLUSION: We conclude that although both fields have their own specific domains of interest, they share common technological developments that tend to be initiated by new developments in biotechnology and computer science.


Assuntos
Biotecnologia/estatística & dados numéricos , Biologia Computacional/estatística & dados numéricos , Informática Médica/estatística & dados numéricos , Processamento de Linguagem Natural , Publicações Periódicas como Assunto/estatística & dados numéricos , Ciência/estatística & dados numéricos , Avaliação da Tecnologia Biomédica , Biotecnologia/tendências , Biologia Computacional/tendências , Previsões , Informática Médica/tendências , Publicações Periódicas como Assunto/tendências , Ciência/tendências , Integração de Sistemas
14.
J Cell Sci ; 119(Pt 10): 2056-64, 2006 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-16638809

RESUMO

GABAB receptors modulate swimming behavior in Paramecium by inhibiting dihydropyridine-sensitive Ca2+ channels via G-proteins. Prolonged occupancy of GABAB receptors by baclofen results in a decrease in GABAB receptor functions. Since changes in the number of cell-surface GABAA receptors have been postulated to be of importance in modulating inhibitory synaptic transmission in neurons, we have studied the cell-surface expression and maintenance of GABAB receptors in P. primaurelia. In this study, we use immunostaining in electron and confocal microscopy to demonstrate that constitutive internalization of GABAB receptors in P. primaurelia is mediated by clathrin-dependent and -independent endocytosis. Indeed, GABAB receptors colocalize with the adaptin complex AP2, which is implicated in the selective recruitment of integral membrane proteins to clathrin-coated vesicles, and with caveolin 1, which is associated with uncoated membrane invaginations. Furthermore, when endocytosis is blocked with hypertonic medium, cytosol acidification, filipin or with a peptide that disrupts the association between amphiphysin and dynamin, the effect of baclofen on swimming is increased. These results suggest that GABAB receptor endocytosis into clathrin-coated and -uncoated vesicles represents an important mechanism in the modulation of swimming behavior in Paramecium.


Assuntos
Paramecium/fisiologia , Receptores de GABA-B/metabolismo , Sequência de Aminoácidos , Animais , Baclofeno/farmacologia , Vesículas Revestidas por Clatrina/efeitos dos fármacos , Vesículas Revestidas por Clatrina/metabolismo , Endocitose/efeitos dos fármacos , Endocitose/fisiologia , Imunofluorescência , Agonistas GABAérgicos/farmacologia , Agonistas dos Receptores de GABA-B , Microscopia Confocal , Dados de Sequência Molecular , Paramecium/efeitos dos fármacos , Paramecium/metabolismo
15.
Biomaterials ; 27(17): 3230-7, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16488007

RESUMO

Purpose of this study was the analysis of the role of density and pore interconnection pathway in scaffolds to be used as bone substitutes. We have considered 2 hydroxyapatite bioceramics with identical microstructure and different macro-porosity, pore size distribution and pore interconnection pathway. The scaffolds were obtained with two different procedures: (a) sponge matrix embedding (scaffold A), and (b) foaming (scaffold B). Bone ingrowth within the two bioceramics was obtained using an established model of in vivo bone formation by exogenously added osteoprogenitor cells. The histological analysis of specimens at different time after in vivo implantation revealed in both materials a significant extent of bone matrix deposition. Interestingly enough, scaffold B allowed a faster occurrence of bone tissue, reaching a steady state as soon as 4 weeks. Scaffold A on the other hand reached a comparable level of bone formation only after 8 weeks of in vivo implantation. Both scaffolds were well vascularised, but larger blood vessels were observed in scaffold A. Here we show that porosity and pore interconnection of osteoconductive scaffolds can influence the overall amount of bone deposition, the pattern of blood vessels invasion and finally the kinetics of the bone neoformation process.


Assuntos
Substitutos Ósseos/química , Osso e Ossos/metabolismo , Fosfatos de Cálcio/química , Cerâmica/química , Animais , Materiais Biocompatíveis , Desenvolvimento Ósseo , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Regeneração Óssea , Celulose/química , Durapatita/química , Cinética , Camundongos , Microscopia , Microscopia Eletrônica de Varredura , Modelos Estatísticos , Osteogênese , Ovinos , Células-Tronco/citologia , Fatores de Tempo , Engenharia Tecidual/métodos
16.
Microsc Res Tech ; 68(5): 290-5, 2005 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-16315238

RESUMO

The number of neurotransmitter receptors on the plasma membrane is regulated by the traffic of intracellular vesicles. Golgi-derived vesicles provide newly synthesized receptors to the cell surface, whereas clathrin-coated vesicles are the initial vehicles for sequestration of surface receptors, which are ultimately degraded or recycled. We have previously shown that GABAB receptors display a punctuate vesicular pattern dispersed on the cell surface and throughout the cytoplasm and are internalized via clathrin-dependent and -independent endocytosis. Here we have studied constitutive GABAB receptor trafficking after internalization in Paramecium primaurelia by confocal laser scanning microscopy and multiple immunofluorescence analysis. After internalization, receptors are targeted to the early endosomes characterized by the molecular markers EEA1 and rab5. Some of these receptors, destined for recycling back to the plasma membrane, traffic from the early endosomes to the endosomal recycling compartment that is characterized by the presence of rab4-immunoreactivity (IR). Receptors that are destined for degradation exit the endosomal pathway at the early endosomes and traffic to the late endosome-lysosome pathway. In fact, some of the GABAB-positive compartments were identified as lysosomal structures by double staining with the lysosomal marker LAMP-1. GABAB vesicle structures also colocalize with TGN38-IR and rab11-IR. TGN38 and rab11 are proteins found in association with post-Golgi and recycling endosomes, respectively.


Assuntos
Paramecium/metabolismo , Receptores de GABA-B/metabolismo , Animais , Endossomos/metabolismo , Imunofluorescência/métodos , Processamento de Imagem Assistida por Computador , Lisossomos/metabolismo , Microscopia Confocal/métodos , Proteínas rab de Ligação ao GTP/metabolismo
17.
IEEE Trans Biomed Eng ; 52(9): 1514-21, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16189964

RESUMO

The objective of this study was to develop a software application that is able to support plastic surgeons interested in applying simulations and soft tissue modeling during presurgical planning activities. By using our user-friendly interface and force-displacement graphs, users can analyze scalp skin behaviors when subjected to stress. Users can 1) determine the dynamic of a general point of scalp skin after the application of a specific force, 2) predict the force needed for displacement of a point, and 3) study the deformation of all the points of the entire scalp based on the force applied. Results showed how users are able to manipulate and analyze mechanical behaviors on a mechanical model rather than on a pure geometric qualitative physiological model. The entire application was developed on a Silicon Graphics workstation.


Assuntos
Procedimentos Cirúrgicos Dermatológicos , Modelos Biológicos , Procedimentos de Cirurgia Plástica/métodos , Cuidados Pré-Operatórios/métodos , Pele/fisiopatologia , Cirurgia Assistida por Computador/métodos , Interface Usuário-Computador , Animais , Fenômenos Biomecânicos/métodos , Gráficos por Computador , Simulação por Computador , Elasticidade , Análise de Elementos Finitos , Humanos , Software , Estresse Mecânico , Viscosidade
18.
Biotechnol Bioeng ; 92(2): 189-98, 2005 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-16007593

RESUMO

Single energy X-ray imaging, due to its low cost and flexibility, is one of the most used and common technique to assess bone state and bone remodeling over time. Standardized X-ray images are needed to compare sets of radiographs for semi-quantitative analyses of tissue remodeling. However, useful mathematical modeling for the analysis of high level radiographic images are not easily available. In order to propose a useful evaluation tool to a wide clinical scenario, we present an innovative calibration algorithm for a semi-quantitative analysis of non-standardized digitized X-ray images. For calibration on a unique standardization scale, three time invariant regions (ROI) of radiographs were selected and analyzed. The accuracy of the normalization method for X-ray films was successfully validated by using an aluminum step wedge for routine X-ray exposures as tool to standardize serial radiographs (Pearson correlation test: R(2) = 0.96). This method was applied to investigate the progression of the new bone deposition within ceramic scaffolds used as osteoconductive substitute in large bone defects taking advantage of a large animal model. This innovative image-processing algorithm allowed the identification and semi-quantification of the bone matrix deposited within the implant. The osteo-integration at the bone-implant interface was also investigated. A progressively increasing bone tissue deposition within the porous bioceramic implant and a progressive osteo-integration was observed during the 12 months of the trial.


Assuntos
Algoritmos , Densidade Óssea , Regeneração Óssea , Substitutos Ósseos/uso terapêutico , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Fraturas da Tíbia/diagnóstico por imagem , Fraturas da Tíbia/cirurgia , Absorciometria de Fóton/métodos , Animais , Cerâmica , Feminino , Consolidação da Fratura , Osseointegração , Porosidade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Ovinos , Resultado do Tratamento
19.
Comput Med Imaging Graph ; 29(5): 385-94, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15893913

RESUMO

In the last decade a number of environments for Computer Supported Plastic Surgery have been presented. Nevertheless, an overall approach for training and intraoperative support is still missing or has not been widely exploited yet. We developed a fully integrated system which allows surgical simulation, planning, and support for computer-guided plastic surgery procedures starting from image acquisition to final intraoperative assistance. The system also provides the user with a radiological workstation able to analyse patient medical images and case studies, with advanced bidimensional and three dimensional image processing functionalities. We intend to demonstrate that such a platform can be built at an affordable cost. The radiological workstation is capable of supporting radiologists and surgeons in real patient case studies and the simulation workstation may be adopted by plastic surgeons in teaching and training of complex surgical planning. Moreover, results of simulation can be used in the operating room with a relatively high benefit in terms of improved accuracy, reduction of surgical risks, and decrease in training costs.


Assuntos
Cirurgia Assistida por Computador/organização & administração , Cirurgia Plástica/educação , Interface Usuário-Computador , Técnicas de Apoio para a Decisão , Humanos , Simulação de Paciente , Sistemas de Informação em Radiologia/organização & administração
20.
FEMS Microbiol Lett ; 238(2): 449-53, 2004 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-15358432

RESUMO

The presence of opioid, beta-adrenergic and cholinergic receptors has been demonstrated in ciliated protozoa, but little is known about gamma-aminobutyric acid (GABA) receptors. In this study we have analyzed the distribution of GABA(A)-type receptor subunits in Paramecium. Confocal laser microscopy using antibodies specific for alpha(1)-, alpha(2)-, alpha(3)-, alpha(6)-, beta(2/3)-, gamma(2)-, epsilon-, lambda-, and theta-subunits showed that most receptors are aggregated in clusters and are distributed both on cell surface and in the cytoplasm. The intensity of labelling of the alpha(6)-, beta(2/3)- and gamma(2)-subunits was more intense than the alpha(1)-, epsilon-, and theta-subunits, suggesting that the former are present in higher concentrations than the latter.


Assuntos
Paramecium/química , Receptores de GABA-A/análise , Animais , Especificidade de Anticorpos , Imunofluorescência , Microscopia Confocal/métodos , Paramecium/imunologia , Receptores de GABA-A/imunologia
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