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ABSTRACT: Teaching dermatologic conditions can be challenging in lecture-style format. A class activity was implemented in a prelicensure nursing course to enhance learning of dermatologic conditions while emphasizing the nursing process, evidence-based treatments, transmission-based precautions, and teamwork. Students worked in teams to identify moulage-based dermatologic conditions and follow the nursing process to develop a plan of care. Students presented their findings to faculty and peers. Positive student feedback on the activity included enhanced teamwork, application of the nursing process, visual emphasis on content, and understanding of holistic care. This activity is an innovative alternative to traditional lecture format.
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Dermatología , Estudiantes de Enfermería , Enseñanza , Humanos , Modelos Anatómicos , Proceso de Enfermería , Aprendizaje Basado en Problemas , Estudiantes de Enfermería/psicología , Dermatología/educaciónRESUMEN
State-of-the-art solvers for in silico cardiac electro-physiology employ the Finite Element Method to solve complex anatomical models. While this is a robust and accurate tech-nique, it requires a high-quality mesh to prevent its accuracy from being severely deteriorated. The generation of a good quality mesh for realistic anatomical models can be very time-consuming, making the translation to the clinics challenging, especially if we try to use patient-specific geometries.Aiming to tackle this challenge, we propose an image-based model generation approach based on the meshfree Mixed Col-location Method. The flexibility provided by this method during model generation allows building meshfree models directly from the image data in an automatic procedure. Furthermore, this approach allows interpreting the simulation results directly in the voxel coordinates system of the image.We simulate electrical propagation in a porcine biventricular model with the proposed method and we compare the results with those obtained using the Finite Element Method. We conclude that the proposed method can generate results that are in good agreement with the Finite Element Method solution, alleviating the requirement of a mesh and user-input during modeling with only minimum efficiency overhead.
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Técnicas Electrofisiológicas Cardíacas , Modelos Anatómicos , Animales , Electrofisiología Cardíaca , Simulación por Computador , Humanos , PorcinosRESUMEN
Acupuncture and moxibustion treatment has been widely spread all over the world because it has few side effects and is effective for ahead sick and incurable disease. However, the treatment is often performed empirically and clinically, and the mechanism and process of the treatment are not yet scientifically elucidated. Therefore, it is required to establish objective and unified research methods and evaluation criteria that incorporate modern Western medicine and scientific and technological viewpoints. In this paper, a human body model is constructed, which includes the internal organs and the meridians for acupuncture and moxibustion treatment based on traditional Chinese medicine using colored Petri nets. This model aims at expressing the relationship between acupoints and internal organs realistically and accurately in acupuncture and moxibustion treatment, and leading to realization of an objective analysis method of the mechanism and process of acupuncture and moxibustion treatment. Firstly, the calculation of the acupoints' efficacy on internal organs is discussed, and measurement equations and model construction methods are proposed. Next, an interface is established as a bridge to connect the internal organs and the meridians with acupoints. By Java language, a simulation system is developed based on the proposed Petri net model. Finally, simulations of acupuncture and moxibustion treatment are performed to verify the validity of model.
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Puntos de Acupuntura , Terapia por Acupuntura/métodos , Medicina Tradicional China/métodos , Modelos Anatómicos , Moxibustión/métodos , Nomogramas , Cuerpo Humano , Humanos , MeridianosRESUMEN
PURPOSE: Nasal delivery is a favorable route for vaccination against most respiratory infections, as antigen deposited in the nasal turbinate and Waldeyer's ring areas induce mucosal and systemic immune responses. However, little is known about the nasal distribution of the vaccines, specifically for infants. METHODS: Anatomical nasal replicas of five subjects, 3-24 months, were developed to assess local intranasal vaccine delivery using MAD Nasal™ device, and understand impact of breathing conditions and administration parameters. High performance liquid chromatography was used to quantify the deposition pattern and determine the delivery efficiency. RESULTS: The delivery efficiency on average for all models was found to be 86.57±14.23%. There were no significant differences in the total delivery efficiency between the models in all cases. However, the regional deposition pattern was altered based on the model and subsequent administration. Furthermore, removing the foam tip from the MAD Nasal™ device, to study the impact of insertion length, did not significantly increase the efficiency within the two models tested, 5- and 16-month. CONCLUSION: Incorporating nasal replicas in testing provided a benchmark to determine the efficiency of a common intranasal vaccine delivery combination product. This proposed platform would allow comparing other potential nasal vaccine delivery devices.
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Modelos Anatómicos , Mucosa Nasal/metabolismo , Vacunación/métodos , Vacunas/farmacocinética , Administración Intranasal , Preescolar , Evaluación Preclínica de Medicamentos/métodos , Humanos , Lactante , Nariz/anatomía & histología , Nariz/diagnóstico por imagen , Impresión Tridimensional , Tomografía Computarizada por Rayos X , Vacunas/administración & dosificaciónRESUMEN
The external field strength according to the international guidelines and standards for human protection are derived to prevent peripheral nerve system pain at frequencies from 300-750 Hz to 1 MHz. In this frequency range, the stimulation is attributable to axon electrostimulation. One limitation in the current international guidelines is the lack of respective stimulation thresholds in the brain and peripheral nervous system from in vivo human measurements over a wide frequency range. This study investigates peripheral stimulation thresholds using a multi-scale computation based on a human anatomical model for uniform exposure. The nerve parameters are first adjusted from the measured data to fit the peripheral nerve in the trunk. From the parameters, the external magnetic field strength to stimulate the nerve was estimated. Here, the conservativeness of protection limits of the international guidelines and standards for peripheral stimulation was confirmed. The results showed a margin factor of 4-6 and 10-24 times between internal and external protection limits of Institute of Electrical and Electronics Engineers standard (IEEE C95.1) and International Commission on Non-Ionizing Radiation Protection guidelines, with the computed pain thresholds.
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Terapia por Estimulación Eléctrica , Modelos Anatómicos , Encéfalo , Campos Electromagnéticos/efectos adversos , Cabeza , Humanos , Campos MagnéticosRESUMEN
The autonomic innervation in the anterior chamber (AC) structures might play an efferent role in neural intraocular pressure (IOP) regulation, the center of which is thought to be located in the hypothalamus. In this study, we identified the efferent pathway from the hypothalamus to the autonomic innervation in the AC structures. Retrograde trans-multisynaptic pseudorabies virus (PRV) expressing green or red fluorescent protein, PRV531 and PRV724, was injected into the right and left AC of five rats, respectively; PRV531 was injected into the right AC of another five rats, and a non-trans-synaptic tracer, FAST Dil, was injected into the right AC of five rats as a control. Fluorescence signals in autonomic ganglia,the spinal cord and the central nervous system (CNS) were observed. Seven days after FAST Dil right AC injection, FAST Dil-labeled neurons were observed in the ipsilateral autonomic ganglia, including the superior cervical ganglion, pterygopalatine ganglion, and ciliary ganglion, but not in the CNS. Four and a half days after PRV531 injection into the right AC, PRV531-labeled neurons could be observed in the ipsilateral autonomic ganglia and bilateral hypothalamus nuclei, especially in the suprachiasmatic nucleus, paraventricular nucleus, dorsomedial hypothalamus, perifornical hypothalamus and ventral mammillary nucleus. Fluorescence signals of PRV531 mainly located in the ipsilateral autonomic preganglionic nuclei (Edinger-Westphal nucleus, superior salivatory nucleus and intermediolateral nucleus), but not in sensory trigeminal nuclei. Four and a half days after PRV531 right AC injection and PRV724 left AC injection, PRV531-labeled, PRV724-labeled, and double-labeled neurons could be observed in the above mentioned bilateral hypothalamus nuclei; but few contralateral infection-involving neurons (including double-labeled neurons) could be detected in the autonomic preganglionic nuclei. Our results indicate that there exist a both crossed and uncrossed hypothalamo-pre-parasympathetic and -pre-sympathetic tracts in the efferent pathways between the bilateral hypothalamic nuclei and the autonomic innervation of the bilateral AC.
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Cámara Anterior/inervación , Sistema Nervioso Autónomo/anatomía & histología , Vías Eferentes/anatomía & histología , Hipotálamo/anatomía & histología , Animales , Presión Intraocular/fisiología , Masculino , Modelos Anatómicos , Modelos Animales , Ratas , Ratas Sprague-DawleyRESUMEN
With the current COVID-19 pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), there is an urgent need for new therapies and prevention strategies that can help curtail disease spread and reduce mortality. The inhibition of viral entry and thus spread is a plausible therapeutic avenue. SARS-CoV-2 uses receptor-mediated entry into a human host via the angiotensin-converting enzyme 2 (ACE2), which is expressed in lung tissue as well as the oral and nasal mucosa, kidney, testes and gastrointestinal tract. The modulation of ACE2 levels in these gateway tissues may be an effective strategy for decreasing disease susceptibility. Cannabis sativa, especially those high in the anti-inflammatory cannabinoid cannabidiol (CBD), has been found to alter gene expression and inflammation and harbour anti-cancer and anti-inflammatory properties. However, its effects on ACE2 expression remain unknown. Working under a Health Canada research license, we developed over 800 new C. sativa cultivars and hypothesized that high-CBD C. sativa extracts may be used to down-regulate ACE2 expression in target COVID-19 tissues. Using artificial 3D human models of oral, airway and intestinal tissues, we identified 13 high-CBD C. sativa extracts that decrease ACE2 protein levels. Some C. sativa extracts down-regulate serine protease TMPRSS2, another critical protein required for SARS-CoV-2 entry into host cells. While our most effective extracts require further large-scale validation, our study is important for future analyses of the effects of medical cannabis on COVID-19. The extracts of our most successful novel high-CBD C. sativa lines, pending further investigation, may become a useful and safe addition to the prevention/treatment of COVID-19 as an adjunct therapy.
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Enzima Convertidora de Angiotensina 2/antagonistas & inhibidores , COVID-19/prevención & control , Cannabis/química , Extractos Vegetales/farmacología , SARS-CoV-2/efectos de los fármacos , Enzima Convertidora de Angiotensina 2/metabolismo , COVID-19/epidemiología , COVID-19/virología , Cannabidiol/farmacología , Cannabidiol/uso terapéutico , Simulación por Computador , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/virología , Modelos Anatómicos , Mucosa Bucal/efectos de los fármacos , Mucosa Bucal/metabolismo , Mucosa Bucal/virología , Pandemias/prevención & control , Extractos Vegetales/química , Extractos Vegetales/uso terapéutico , Mucosa Respiratoria/efectos de los fármacos , Mucosa Respiratoria/metabolismo , Mucosa Respiratoria/virología , SARS-CoV-2/metabolismo , SARS-CoV-2/patogenicidad , Internalización del Virus/efectos de los fármacos , Tratamiento Farmacológico de COVID-19RESUMEN
Introduction Advanced, Monte Carlo (MC) based dose calculation algorithms, determine absorbed dose as dose to medium-in-medium (Dm,m) or dose to water-in-medium (Dw,m). Some earlier studies identified the differences in the absorbed doses related to the calculation mode, especially in the bone density equivalent (BDE) media. Since the calculation algorithms built in the treatment planning systems (TPS) should be dosimetrically verified before their use, we analyzed dose differences between two calculation modes for the Elekta Monaco TPS. We compared them with experimentally determined values, aiming to define a supplement to the existing TPS verification methodology. Materials and methods In our study, we used a 6 MV photon beam from a linear accelerator. To evaluate the accuracy of the TPS calculation approaches, measurements with a Farmer type chamber in a semi-anthropomorphic phantom were compared to those obtained by two calculation options. The comparison was made for three parts of the phantom having different densities, with a focus on the BDE part. Results Measured and calculated doses were in agreement for water and lung equivalent density materials, regardless of the calculation mode. However, in the BDE part of the phantom, mean dose differences between the calculation options ranged from 5.7 to 8.3%, depending on the method used. In the BDE part of the phantom, neither of the two calculation options were consistent with experimentally determined absorbed doses. Conclusions Based on our findings, we proposed a supplement to the current methodology for the verification of commercial MC based TPS by performing additional measurements in BDE material.
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Densidad Ósea , Método de Montecarlo , Planificación de la Radioterapia Asistida por Computador/métodos , Algoritmos , Humanos , Modelos Anatómicos , Aceleradores de Partículas , FotonesRESUMEN
OBJECTIVES: This study aims to investigate the effects of hyperbaric oxygen (HBO) therapy and platelet-rich plasma (PRP) on the regeneration of osteochondral defects of the rats, and the synergistic effect of this combined treatment. MATERIALS AND METHODS: This randomized, controlled, and interventional animal study was conducted between May 2014 and August 2014 Osteochondral regeneration was evaluated in four treatment groups (control, PRP, HBO, and HBO+PRP groups) at the 30th day after iatrogenic injury. Thirty-two female Wistar albino rats (weighing 248-305 g) underwent arthrotomy and osteochondral surgery on left knees. The regenerations of defects were then examined histologically by the modified version of O'Driscoll score. RESULTS: Groups that were treated with either HBO or PRP alone regenerated significantly better than the control group (p=0.01), while no significant difference was found between the HBO- and PRP-treated groups (p>0.05). The defects in group 4 (treated with both HBO and PRP) regenerated significantly better than the control group, the HBO-treated group alone, and the PRP-treated group alone (p=0.01). CONCLUSION: The results of this study showed a synergistic effect of HBO and PRP on knee cartilage regeneration. However, the possible underlying mechanisms should be the subject of future researches. The aggregation and activation of growth factors released from platelets whose activation is increased in the hyperbaric environment may explain this effect. This may result in a better regeneration than the effect of PRP or HBO alone.
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Cartílago , Oxigenoterapia Hiperbárica/métodos , Articulación de la Rodilla/cirugía , Plasma Rico en Plaquetas/metabolismo , Regeneración/efectos de los fármacos , Animales , Cartílago/efectos de los fármacos , Cartílago/lesiones , Cartílago/fisiología , Terapia Combinada/métodos , Modelos Anatómicos , Ratas , Ratas Wistar , Resultado del Tratamiento , Cicatrización de Heridas/efectos de los fármacosRESUMEN
The aim of this randomized, controlled animal exploratory trial was to investigate the influence of local application of aminobisphosphonate pamidronate during the socket preservation procedure. Mandibular premolars were extracted in five Göttingen minipigs. Two animals underwent socket preservation using BEGO OSS (n = 8 sockets) and three animals using BEGO OSS + Pamifos (15 mg) (n = 12 sockets). After jaw impression, cast models (baseline, eight weeks postoperative) were digitized using an inLab X5 scanner (Dentsply Sirona) and the generated STL data were superimposed and analyzed with GOM Inspect 2018 (GOM, Braunschweig). After 16 weeks, the lower jaws were prepared and examined using standard histological methods. In the test group (BEGO OSS + pamidronate), buccooral dimensional loss was significantly lower, both vestibulary (0.80 ± 0.57 mm vs. 1.92 ± 0.63 mm; p = 0.00298) and lingually (1.36 ± 0.58 mm vs. 2.56 ± 0.65 mm; p = 0.00104) compared with the control group (BEGO OSS). The test group showed a significant difference between vestibular and lingual dimensional loss (p = 0.04036). Histology showed cortical and cancellous bone in the alveolar sockets without signs of local inflammation. Adjuvant application of pamidronate during socket preservation reduces alveolar dimensional loss significantly. Further investigations with regard to dose-response relationships, volume effects, side effects, and a verification of the suitability in combination with other bone substitute materials (BSMs) are necessary.
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Pérdida de Hueso Alveolar/prevención & control , Conservadores de la Densidad Ósea/uso terapéutico , Pamidronato/uso terapéutico , Complicaciones Posoperatorias/prevención & control , Extracción Dental/métodos , Pérdida de Hueso Alveolar/etiología , Animales , Conservadores de la Densidad Ósea/administración & dosificación , Regeneración Ósea , Modelos Anatómicos , Pamidronato/administración & dosificación , Distribución Aleatoria , Porcinos , Porcinos Enanos , Extracción Dental/efectos adversos , Alveolo Dental/patología , Alveolo Dental/cirugíaRESUMEN
BACKGROUND: Traditional Chinese medicine (TCM) massage has a better effect on treating infant diarrhea compared to medical treatment. The TCM doctors need to be trained to master professional massage techniques. Traditional Chinese massage training relies on the students' understanding ability, and cannot accurately record the students' operating information. This situation leads to insufficient clinical massage skills of the students. OBJECTIVE: This paper proposes a novel massage training platform to quantitatively perceive the massage techniques of students. METHODS: The paper proposed two types of flexible array sensors, which are arranged and placed into the bionic baby according to the position of the human acupoints. The massage techniques of the training object can be analyzed and evaluated during the massage process by studying the voltage from pressure sensors when the participants massage the bionic infant. RESULTS: A medical student was invited to conduct the massage training experiment, and the massage information included the operating strength, massage frequency and the massage direction, which were recorded and analyzed through the training platform. CONCLUSION: The platform can perceive the parameters related to the massage technique of students and can be used for medical training.
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Diarrea/terapia , Masaje/educación , Modelos Anatómicos , Puntos de Acupuntura , Competencia Clínica , Humanos , LactanteRESUMEN
Student engagement is known to have several positive effects on learning outcomes and can impact a student's university experience. High levels of engagement in content-heavy subjects can be difficult to attain. Due to a major institutional restructure, the anatomy prosection laboratory time per subject was dramatically reduced. In response, the authors set out to redesign their anatomy units with a focus on engaging the learning activities that would increase time-on-task both within and outside of the classroom. One of these curriculum changes was the implementation of a suite of anatomy learning activities centered on sets of three-dimensional printed upper limb skeleton models. A two-part mixed-method sequential exploratory design was used to evaluate these activities. Part one was a questionnaire that evaluated the students' engagement with and perceptions of the models. Part two involved focus groups interviews, which were an extension of the survey questions in part one. The results of the study indicated that the majority of students found the models to be an engaging resource that helped improve their study habits. As a result, students strongly felt that the use of the models inspired greater academic confidence and overall better performance in their assessments. Overall, the models were an effective way of increasing the engagement and deep learning, and reinforced previous findings from the medical education research. Future research should investigate the effects of these models on student's grades within osteopathy and other allied health courses.
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Anatomía/educación , Educación de Pregrado en Medicina/organización & administración , Modelos Anatómicos , Impresión Tridimensional , Aprendizaje Basado en Problemas/métodos , Curriculum , Educación de Pregrado en Medicina/métodos , Evaluación Educacional/estadística & datos numéricos , Grupos Focales , Humanos , Imagenología Tridimensional , Modelos Educacionales , Medicina Osteopática/educación , Evaluación de Programas y Proyectos de Salud , Investigación Cualitativa , Participación de los Interesados , Estudiantes de Medicina/psicología , Estudiantes de Medicina/estadística & datos numéricos , Encuestas y Cuestionarios/estadística & datos numéricos , Universidades/organización & administraciónRESUMEN
PURPOSE: This study would like to develop a novel model similar to human prostate in terms of its texture profile, sensation upon resection, and anatomical hallmarks for resident transurethral resection of the prostate (TUR-P) training. METHODS: Ten phantom designs were proposed, using broadly available ingredients and a homemade protocol. Three steps of evaluation and development were done: objective measurement measuring texture profile (e.g. hardness, elasticity, cohesiveness/consistency, and adhesiveness/stickiness) using TA-XT2i Texture Analyzer (Llyod Instruments, Ametek Inc) to compare the designs with human prostate, finding the most similar design to prostate; expert consensus by a panel of urologist/senior residents comparing the simulation of TUR-P on the selected design with pre-existing control phantom; and anatomical design development using 3D printing for molding. RESULTS: Texture profile analysis for mean hardness, elasticity, cohesiveness/consistency, and adhesiveness/stickiness of human prostate was 3753.4 ± 673.4, 85 ± 1.9, 0.7 ± 0.03, and 0, respectively, and design IX was the most similar to human prostate (3660.7 ± 465.6, 87.0 ± 2.5, 0.6 ± 0.05, 0). Furthermore, expert consensus showed superiority of design IX compared with pre-existing control phantom (16.95 ± 1.36 vs 8.86 ± 3.10; P < 0.001). Most of the respondents agreed that the texture, consistency, and phantom ability to mimic human prostate upon resection were similar with human prostate, though hallmarks of the prostate e.g. veromontanum, and lobes were lacking. We used these feedbacks to develop a mold, designed to produce these important anatomical hallmarks. CONCLUSION: This study developed a cost-effective prostate model from a food-based design that is similar to human prostate in terms of its texture and sensation upon TUR-P resection provided with important anatomical hallmarks.
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Internado y Residencia/métodos , Modelos Anatómicos , Próstata , Resección Transuretral de la Próstata/educación , Animales , Humanos , Masculino , Fantasmas de ImagenRESUMEN
We previously reported the feasibility and efficacy of a simulation-guided clinical catheter ablation of atrial fibrillation (AF) in an in-silico AF model. We developed a highly efficient realistic AF model reflecting the patient endocardial voltage and local conduction and tested its clinical feasibility. We acquired > 500 endocardial bipolar electrograms during right atrial pacing at the beginning of the AF ablation procedures. Based on the clinical bipolar electrograms, we generated simulated voltage maps by applying fibrosis and local activation maps adjusted for the fiber orientation. The software's accuracy (CUVIA2.5) was retrospectively tested in 17 patients and feasibility prospectively in 10 during clinical AF ablation. Results: We found excellent correlations between the clinical and simulated voltage maps (R = 0.933, p < 0.001) and clinical and virtual local conduction (R = 0.958, p < 0.001). The proportion of virtual local fibrosis was 15.4, 22.2, and 36.9% in the paroxysmal AF, persistent AF, and post-pulmonary vein isolation (PVI) states, respectively. The reconstructed virtual bipolar electrogram exhibited a relatively good similarities of morphology to the local clinical bipolar electrogram (R = 0.60 ± 0.08, p < 0.001). Feasibility testing revealed an in situ procedural computing time from the clinical data acquisition to wave-dynamics analyses of 48.2 ± 4.9 min. All virtual analyses were successfully achieved during clinical PVI procedures. We developed a highly efficient, realistic, in situ procedural simulation model reflective of individual anatomy, fiber orientation, fibrosis, and electrophysiology that can be applied during AF ablation.
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Fibrilación Atrial/patología , Fibrilación Atrial/cirugía , Ablación por Catéter , Atrios Cardíacos/patología , Anciano , Fibrilación Atrial/fisiopatología , Ablación por Catéter/métodos , Simulación por Computador , Técnicas Electrofisiológicas Cardíacas , Estudios de Factibilidad , Femenino , Fibrosis , Atrios Cardíacos/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Modelos Anatómicos , Modelos Cardiovasculares , Estudios Retrospectivos , Programas InformáticosRESUMEN
In early twentieth-century France, syphilis and its controversial status as a hereditary disease reigned as a chief concern for physicians and public health officials. As syphilis primarily presented visually on the surface of the skin, its study fell within the realms of both dermatologists and venereologists, who relied heavily on visual evidence in their detection, diagnosis, and treatment of the disease. Thus, in educational textbooks, atlases, and medical models, accurately reproducing the visible signposts of syphilis - the colour, texture, and patterns of primary chancres or secondary rashes - was of preeminent importance. Photography, with its potential claims to mechanical objectivity, would seem to provide the logical tool for such representations. Yet photography's relationship to syphilographie warrants further unpacking. Despite the rise of a desire for mechanical objectivity charted in the late nineteenth century, artist-produced, three-dimensional, wax-cast moulages coexisted with photographs as significant educational tools for dermatologists; at times, these models were further mediated through photographic reproduction in texts. Additionally, the rise of phototherapy complicated this relationship by fostering the clinical equation of the light-sensitive photographic plate with the patient's skin, which became the photographic record of disease and successful treatment. This paper explores these complexities to delineate a more nuanced understanding of objectivity vis-à-vis photography and syphilis. Rather than a desire to produce an unbiased image, fin-de-siècle dermatologists marshalled the photographic to exploit the verbal and visual rhetoric of objectivity, authority, and persuasion inextricably linked to culturally constructed understandings of the photograph. This rhetoric was often couched in the Peircean concept of indexicality, which physicians formulated through the language of witness, testimony, and direct connection.
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Anatomía Artística/historia , Ilustración Médica/historia , Modelos Anatómicos , Fotograbar/historia , Sífilis/historia , Atlas como Asunto/historia , Distinciones y Premios , Dermatología/educación , Dermatología/historia , Francia , Historiografía , Historia del Siglo XIX , Historia del Siglo XX , Humanos , Sífilis/patología , Sífilis Congénita/historia , Venereología/educación , Venereología/historiaRESUMEN
The objective of this study was to evaluate the benefits of a new extraction process, the ipowder® technology, applied to Melissa officinalis L. Compared to M. officinalis ground dry leaves, the ipowder® had a similar phytochemical fingerprint but contained twice the concentration of rosmarinic acid (by HPTLC and HPLC) and had a two-fold greater antioxidant activity (DPPH* method). In vitro digestion experiments (TIM-1 model) showed better availability of rosmarinic acid for intestinal absorption with the ipowder® than with ground dry leaves, manifested by a three-fold reduction in the quantity of ingested product needed for delivery of the same amount of rosmarinic acid into the upper gastro-intestinal tract. This study shows that the ipowder® technology preserves all the original plant compounds intact while making some active ingredients more accessible and available to exert their effects. To obtain a given effect, the amount of ipowder® extract to ingest will therefore be lower; a reduction in the daily dosage will be more convenient for the patient and will improve patient compliance with supplementation.
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Antioxidantes/química , Cinamatos/química , Depsidos/química , Intestinos/efectos de los fármacos , Melissa , Extractos Vegetales/química , Estómago/efectos de los fármacos , Antioxidantes/farmacología , Cinamatos/farmacología , Depsidos/farmacología , Composición de Medicamentos , Humanos , Técnicas In Vitro , Modelos Anatómicos , Fitoterapia , Hojas de la Planta/química , Ácido RosmarínicoRESUMEN
BACKGROUND AND OBJECTIVES: During thermal heating surgical procedures such as electrosurgery, thermal ablative treatment and hyperthermia, soft tissue deformation due to surgical tool-tissue interaction and patient movement can affect the distribution of thermal energy induced. Soft tissue temperature must be obtained from the deformed tissue for precise delivery of thermal energy. However, the classical Pennes bio-heat transfer model can handle only the static non-moving state of tissue. In addition, in order to enable a surgeon to visualise the simulated results immediately, the solution procedure must be suitable for real-time thermal applications. METHODS: This paper presents a formulation of bio-heat transfer under the effect of soft tissue deformation for fast or near real-time tissue temperature prediction, based on fast explicit dynamics finite element algorithm (FED-FEM) for transient heat transfer. The proposed thermal analysis under deformation is achieved by transformation of the unknown deformed tissue state to the known initial static state via a mapping function. The appropriateness and effectiveness of the proposed formulation are evaluated on a realistic virtual human liver model with blood vessels to demonstrate a clinically relevant scenario of thermal ablation of hepatic cancer. RESULTS: For numerical accuracy, the proposed formulation can achieve a typical 10-3 level of normalised relative error at nodes and between 10-4 and 10-5 level of total errors for the simulation, by comparing solutions against the commercial finite element analysis package. For computation time, the proposed formulation under tissue deformation with anisotropic temperature-dependent properties consumes 2.518 × 10-4â ms for one element thermal loads computation, compared to 2.237 × 10-4â ms for the formulation without deformation which is 0.89 times of the former. Comparisons with three other formulations for isotropic and temperature-independent properties are also presented. CONCLUSIONS: Compared to conventional methods focusing on numerical accuracy, convergence and stability, the proposed formulation focuses on computational performance for fast tissue thermal analysis. Compared to the classical Pennes model that handles only the static state of tissue, the proposed formulation can achieve fast thermal analysis on deformed states of tissue and can be applied in addition to tissue deformable models for non-linear heating analysis at even large deformation of soft tissue, leading to great translational potential in dynamic tissue temperature analysis and thermal dosimetry computation for computer-integrated medical education and personalised treatment.
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Calor , Neoplasias Hepáticas/diagnóstico por imagen , Hígado/diagnóstico por imagen , Técnicas de Ablación , Algoritmos , Simulación por Computador , Electrocirugia , Análisis de Elementos Finitos , Humanos , Hipertermia Inducida , Imagenología Tridimensional , Modelos Lineales , Hígado/irrigación sanguínea , Neoplasias Hepáticas/irrigación sanguínea , Modelos Anatómicos , Modelos CardiovascularesRESUMEN
The present study examined the kinematics and biomechanical parameters of the head of a person thrown forward by the judo technique 'Seoi-nage'. A judo expert threw an anthropomorphic test device (the POLAR dummy) five times. Kinematics data were obtained with a high-speed digital video camera. Linear and angular accelerations of the head were measured by accelerometers mounted at the center of gravity of the dummy's head. When Seoi-nage was performed, the dummy fell forward accompanied by contacting the anterior parietal regions of the head to the tatami, and the linear and angular accelerations of most axes reached peak values when the head contacted the tatami. Peak resultant linear and angular accelerations were 20.3 ± 9.8 G and 1890.1 ± 1151.9 rad/s2, respectively (means ± standard deviation). Peak values in linear and angular acceleration did not significantly differ between the three directional axes. Absolute angular accelerations in all axes observed in Seoi-nage were high and the resultant value was approximately equal to the already reported in Ouchi-gari, one of the predominant techniques causing judo-related acute subdural hematoma. However, the remarkable increase of linear acceleration in the longitudinal direction and/or angular acceleration in the sagittal plane, as previously reported in techniques being thrown backward (i.e., Ouchi-gari and Osoto-gari), was not detected. The likely mechanism of acute subdural hematoma caused by Seoi-nage is that a large angular acceleration causes large strains and deformations of the brain surface and subsequent rupture of cortical vessels.
Asunto(s)
Fenómenos Biomecánicos/fisiología , Lesiones Encefálicas/fisiopatología , Encéfalo/irrigación sanguínea , Movimientos de la Cabeza/fisiología , Artes Marciales/lesiones , Artes Marciales/fisiología , Aceleración , Antropometría , Hematoma Subdural/fisiopatología , Humanos , Modelos Anatómicos , Orientación/fisiología , Postura/fisiologíaRESUMEN
Transurethral resection of the prostate (TURP) is a minimally invasive endoscopic procedure that requires experience and skill of the surgeon. To permit surgical training under realistic conditions we report a novel phantom of the human prostate that can be resected with TURP. The phantom mirrors the anatomy and haptic properties of the gland and permits quantitative evaluation of important surgical performance indicators. Mixtures of soft materials are engineered to mimic the physical properties of the human tissue, including the mechanical strength, the electrical and thermal conductivity, and the appearance under an endoscope. Electrocautery resection of the phantom closely resembles the procedure on human tissue. Ultrasound contrast agent was applied to the central zone, which was not detectable by the surgeon during the surgery but showed high contrast when imaged after the surgery, to serve as a label for the quantitative evaluation of the surgery. Quantitative criteria for performance assessment are established and evaluated by automated image analysis. We present the workflow of a surgical simulation on a prostate phantom followed by quantitative evaluation of the surgical performance. Surgery on the phantom is useful for medical training, and enables the development and testing of endoscopic and minimally invasive surgical instruments.
Asunto(s)
Fantasmas de Imagen , Próstata/cirugía , Resección Transuretral de la Próstata , Humanos , Imagen por Resonancia Magnética , Masculino , Modelos Anatómicos , Próstata/diagnóstico por imagen , UltrasonografíaRESUMEN
The anatomy of the pallidothalamic tracts, including the ansa lenticularis, lenticular fasciculus, and thalamic fasciculus (field H1 of Forel), should be elucidated by neurosurgeons and neuroscientists who study deep brain stimulation. In this study, serially sectioned images of a human cadaver head were employed to overcome the limitations of existing methods to observe the pallidothalamic tracts. Owing to the high resolution and real color of the sectioned images, 28 structures, including the pallidothalamic tracts and mammillothalamic fasciculus, were identified. The structures were segmented and made into surface models, which are helpful in improving the stereoscopic understanding. Observing the sectioned images and surface models may help in understanding the detailed anatomy of the pallidothalamic tracts. The new findings, such as the spatial relationship of the tracts, were summarized in a schematic figure. Moreover, to elucidate the anatomical structures along the course of deep brain stimulation, virtual electrodes were inserted into the surface models. The sectioned images and surface models of this study are expected to enhance the understanding of the pallidothalamic tract anatomy. A portable document format file containing the surface models and the sectioned images can be freely downloaded from the authors' homepage. Clin. Anat. 32:66-76, 2019. © 2019 Wiley Periodicals, Inc.