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1.
Ann Anat ; 250: 152155, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37683899

RESUMO

BACKGROUND: Mental health problems are common in medical professionals and their development already starts at the undergraduate level. Studies on medical students can replicate higher prevalence for depression and burnout in this group, but they normally compare semester cohorts in an anonymized, cross-sectional approach and without a preventive perspective. METHODS: We surveyed medical students at the beginning and end of their medical curriculum and collected data on burnout, depressivity, work related experience and salutogenesis parameters with validated self-administered questionnaires. Most remarkably we obtained the data from the same 58 individuals after 5.5 years, representing data of the highest quality in order to compare the mental health status at the beginning and the end of our students´ medical curriculum. RESULTS: Our results not only show a severe exacerbation of physical, mental and emotional burnout in the participants at the end of their studies. The students also do not seem to have sufficient personal (resilience) or social resources (e.g. experience of social support) for coping with their mental health problems around the time of their graduation. CONCLUSIONS: Our participants reflect a development of mental health during their medical studies at university that is paving the way to the devastating prevalence of mental disorders and suicide in health professionals. From our results we derive an urgent need to integrate self-care and active coping in the learning goals of medical curricula.


Assuntos
Esgotamento Profissional , Estudantes de Medicina , Humanos , Saúde Mental , Estudantes de Medicina/psicologia , Estudos Longitudinais , Adaptação Psicológica , Inquéritos e Questionários , Esgotamento Profissional/epidemiologia , Esgotamento Profissional/psicologia
2.
Ann Anat ; 250: 152152, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37633501

RESUMO

BACKGROUND: Compression of the ulnar nerve at the elbow within the cubital tunnel is related to the anatomical structures and is generally believed to be caused by Osborne's ligament (also known as the cubital retinaculum). However, in rare cases an anatomical variation of the developmental peculiarity of a remaining anconeus epitrochlearis muscle may be responsible for the disease. METHODS: We present a series of five cases in which an anconeus epitrochlearis muscle was found as the cause of illness. RESULTS: All patients presented with typical symptoms of numbness and tingling in the hand and ulnar fingers, and recurring pain as well as weakness of the ulnar innervated muscles. With neurophysiologically confirmed diminished nerve conduction velocity and unsuccessful conservative treatment, surgical decompression revealed an anconeus epitrochlearis muscle as the reason of compression. Full symptom relief was achieved immediately after the procedure in all cases. CONCLUSIONS: This article strives to call attention to this entity when diagnosing ulnar nerve compression. Myectomy and medial epicondylectomy is the preferred treatment option in such cases.


Assuntos
Síndrome do Túnel Ulnar , Articulação do Cotovelo , Humanos , Síndrome do Túnel Ulnar/cirurgia , Síndrome do Túnel Ulnar/diagnóstico , Síndrome do Túnel Ulnar/etiologia , Cotovelo , Músculo Esquelético/cirurgia , Nervo Ulnar/cirurgia
3.
Br J Haematol ; 201(2): 222-226, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36793157

RESUMO

Immune thrombocytopenia (ITP) was reported as a rare complication of COVID-19 vaccines. We conducted a retrospective single-center analysis of all ITP cases detected in 2021 and compared the quantity with the pre-vaccination years, from 2018 to 2020. In 2021, a two-fold increase in ITP cases was identified compared to previous years; 11 of 40 cases (27.5%) were considered COVID-19-vaccine related. Our study highlights an increase in ITP cases at our institution, probably related to COVID-19 vaccinations. Further studies are needed to investigate this finding globally.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Púrpura Trombocitopênica Idiopática , Trombocitopenia , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Programas de Imunização , Incidência , Púrpura Trombocitopênica Idiopática/induzido quimicamente , Púrpura Trombocitopênica Idiopática/epidemiologia , Estudos Retrospectivos , Trombocitopenia/induzido quimicamente , Trombocitopenia/epidemiologia , Vacinação/efeitos adversos
4.
Folia Morphol (Warsz) ; 82(2): 359-367, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35239179

RESUMO

BACKGROUND: The biceps brachii (BB) muscle is one of the three muscles located in the anterior compartment of the arm. Its insertion consists of two parts. The first part - main tendon - attached in the radial tuberosity and the second part - lacertus fibrosus (LF) - in the fascia of the forearm flexors. The intention of research was to reveal the morphological diversity of the insertion of this muscle. Thanks to the results of this work, have been created a classification of the distal attachment of BB. The results of that research can be used to further develop surgical procedures in the given region. MATERIALS AND METHODS: Eighty (40 left, and 40 right, 42 female, 38 male) upper limbs fixed in 10% formalin solution were examined. RESULTS: We observed three types of the insertion of the BB. Type I was characterised by a single tendon and occurred most frequently in 78.75% of the examined limbs. The second most common type was type II which was characterised by a double tendon and was observed in 13.75% of all the limbs. The last and least common was type III which was characterised by three tendons and occurred in 7.5% of the examined limbs. Additionally, the type of LF was analysed. In 8 (10%) specimens it was absent, i.e. in 2 specimens with type II insertion and 6 specimens with type III (p = 0.0001). Therefore, it may be deduced that type III BB insertion tendon predisposes to LF deficiency. CONCLUSIONS: The BB tendon is characterised by high morphological variability. The new classification proposes three types of distal attachment: type I - one tendon; type II - two separated band-shaped tendons; type III - three separated band-shaped tendons. The presence of type III BB tendon predisposes to a lack of LF.


Assuntos
Braço , Músculo Esquelético , Masculino , Feminino , Humanos , Músculo Esquelético/anatomia & histologia , Tendões/anatomia & histologia , Rádio (Anatomia) , Fáscia , Cadáver
5.
Ann Anat ; 244: 151983, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35853532

RESUMO

PURPOSE: The ligamentum mucosum is a ligamentous structure within the synovial layer of the knee joint capsule. It usually arises from the infrapatellar fat pad and is inserted into the intercondylar notch of the femur. In recent years, more attention has been paid to this structure because of its clinical significance. Despite the growing attention, the complex morphology of the ligamentum mucosum has led to many misunderstandings among the scientists and clinicians. Therefore, the main objective of this study was to characterize the morphology of the ligamentum mucosum and its attachment points, classify it, and evaluate its prevalence. METHODS: Classical anatomical dissection was performed on 70 lower limbs of human fetuses fixed in 10% formalin solution. Morphology was carefully assessed, and morphometric measurements were performed. The types revealed were classified. RESULTS: The ligamentum mucosum was present in 100% of all 70 specimens examined. Two types were detected. Type I (65.71%) - "cord-like". This type was the most common and is characterized by a single longitudinal ligament. The proximal attachment of the ligamentum mucosum was located in the middle of the infrapatellar fat, and the distal attachment was at the tip of the intercondylar notch. Type II (34.29%) - "vertical septum". This type is less common, but its morphology is much more complex compared to type I. It is wider and thicker than type I. Proximally, it is attached to the infrapatellar fat pad and distally through the entire intercondylar notch down to the anterior surface of the anterior cruciate ligament. It divides the joint cavity into medial and lateral sides. CONCLUSION: The ligamentum mucosum exhibits high morphologic variability, and the view that it is a vestigial remnant of the embryologic development of the knee should be reconsidered. We have proposed an anatomical classification of its types in human fetuses, which is a valuable addition to existing knowledge and will hopefully change the approach of clinicians and scientists.


Assuntos
Lesões do Ligamento Cruzado Anterior , Articulação do Joelho , Humanos , Articulação do Joelho/anatomia & histologia , Ligamento Cruzado Anterior , Joelho , Formaldeído
6.
J Mech Behav Biomed Mater ; 133: 105292, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35689988

RESUMO

Numerical simulations are a valuable tool in the field of tissue engineering for cartilage repair and can help to understand which mechanical properties affect the behavior of chondrocytes and contribute to the success or failure of surrogate materials as implants. However, special attention needs to be paid when identifying corresponding material parameters in order to provide reliable numerical predictions of the material's response. In this study, we identify hyperelastic material parameters for numerical simulations in COMSOL Multiphysics® v. 5.6 for human articular cartilage and two surrogate materials, commercially available ChondroFillerliquid, and oxidized alginate-gelatin (ADA-GEL) hydrogels. We consider several hyperelastic isotropic material models and provide separate parameter sets for the unconditioned and the conditioned material response, respectively, based on previously generated experimental data including both compression and tension experiments. We compare a direct parameter identification approach assuming homogeneous deformation throughout the specimen and an inverse approach, where the experiments are simulated using a finite element model with realistic boundary conditions in COMSOL Multiphysics® v. 5.6. We demonstrate that it is important to consider both compression and tension data simultaneously and to use the inverse approach to obtain reliable parameters. The one-term Ogden model best represents the unconditioned response of cartilage, while the conditioned response of cartilage and ADA-GEL is equally well represented by the two-term Ogden and five-term Mooney-Rivlin models. The five-term Mooney-Rivlin model is also most suitable to model the unconditioned response of ADA-GEL. For ChondroFillerliquid, we suggest using the five-term Mooney-Rivlin or two-term Ogden model for the unconditioned and the two-term Ogden model for the conditioned material response. These results will help to choose appropriate material models and parameters for simulations of whole joints or to advance mechanical-stimulation assisted cartilage tissue engineering in the future.


Assuntos
Cartilagem Articular , Cartilagem Articular/fisiologia , Condrócitos , Elasticidade , Análise de Elementos Finitos , Gelatina , Humanos , Hidrogéis , Estresse Mecânico , Engenharia Tecidual
7.
Ann Anat ; 243: 151920, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35278660

RESUMO

BACKGROUND: The purpose of this study was to characterize the morphology of the fibularis tertius (FT) in human fetuses, and to provide a classification based on its modes of origin in human fetuses. METHODS: The material comprised 100extremities from 50 spontaneously aborted human fetuses (19 male, 31 female, 100 lowerlimbs in total), aged 18-38 weeks of gestation. These were dissected and the presence or absence of the FT muscle as well as the type of its proximal attachment were determined, and the FT was measured morphometrically. RESULTS: The FT was present in 50% of fetuses. Four types of FT muscle origin were identified. The most common was Type 2, characterized by an origin on the middle third of the fibula and the intermuscular septum. Three other types were observed: Type 1 with an origin located on proximal third of the fibula and to the intermuscular septum, Type 3 characterized by an absent muscle belly, and an independent tendon originating from the that of the extensor digitorum longus, and Type 4 with an origin located on the distal third of the fibula and the intermuscular septum. CONCLUSIONS: The fibularis tertius demonstrates high morphological variability, with the most common origin located on third of the fibula and to the intermuscular septum.


Assuntos
Perna (Membro) , Músculo Esquelético , Cadáver , Feminino , Feto , Humanos , Perna (Membro)/anatomia & histologia , Masculino , Músculo Esquelético/anatomia & histologia , Tendões/anatomia & histologia
8.
Ann Anat ; 240: 151856, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34793958

RESUMO

BACKGROUND: Traditionally, dynamic and functional anatomy, in particular the dynamic anatomy of the neck, is studied on cadaveric material. However, the development of in vivo visualization technologies and in silico modeling has made it possible to expand these possibilities. Despite significant progress in the study of dynamic and functional anatomy of the neck by means of in silico methods, the issues of validating the developed models and taking into account the pronounced nonlinearity of soft tissues as well as local anisotropy remain open. The aim of this study was to develop a virtual dynamic anatomical model of the human neck and reproduce the dynamic processes in the cervical spine from this model using the finite element method. MATERIALS AND METHODS: Reverse engineering was used to generate a dynamic anatomical model of the neck from CT data (both male, 24 and 22 years old). Two segments of the cervical spine (C3-C5, C2-T1) were isolated from the resulting model for finite element analysis. Finite element mesh generation and contact interactions were performed using the HyperMesh software (Altair Engineering Inc, Troy, Michigan, USA). The anisotropic hyperelastic Holzapfel-Gasser-Ogden model was used to describe the material behavior of the fibrous rings of the disc. Material modeling and finite element analysis were performed using Abaqus CAE 6.14 software (Simulia, Johnston, Rhode Island, USA). RESULTS: A technique for creating a virtual dynamic anatomical model of the neck was elaborated and implemented. The model includes 79 major anatomical structures of the neck segmented from radiological data. A finite element analysis of the cervical spine was performed. The results of finite element analysis of the C3-C5 segment under axial load were compared with in vitro data. The proposed model shows nonlinear deformation of the disc under static loading; the model predicted displacement values agree well with the experimental ones. The displacement of the С3-С5 central vertebra with an axial load of 800 N reaches a value of 0.65 mm. For the segment C2-T1, data on intradiscal pressure, stress plots and displacements during flexion were obtained. The maximum stress value of 10.036 MPa is observed in the C3-C4 disc. CONCLUSION: Simulation results using the proposed methodology are in good agreement with experimental data. The generated biomechanical models allow describing dynamic phenomena in the cervical spine and obtaining a wide range of quantitative properties of anatomical objects, which are otherwise inaccessible to classical methods for studying dynamic and functional anatomy.


Assuntos
Vértebras Cervicais , Pescoço , Fenômenos Biomecânicos , Vértebras Cervicais/diagnóstico por imagem , Análise de Elementos Finitos , Humanos , Masculino , Amplitude de Movimento Articular
9.
Folia Morphol (Warsz) ; 81(2): 451-457, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33899207

RESUMO

BACKGROUND: In adults, the fibularis tertius (FT) demonstrates great morphological variation. The present study classifies the types of FT insertion in human foetuses and compares their prevalence to the prevailing classification among adults. MATERIALS AND METHODS: Fifty spontaneously-aborted human foetuses (19 male, 31 female, 100 upper limbs in total) aged 18-38 weeks of gestation at death were examined. The foetuses were obtained from spontaneous abortion after parental consent. The study was performed in accordance with the legal procedures in force in Poland and with the Body Donation Programme for both adults and foetuses. RESULTS: The most common type of FT found was type VI (32%), characterised by a bifurcated distal attachment: a main tendon inserting onto the base of the fourth metatarsal bone, and accessory bands inserting onto the fourth interosseous space. Five other types were observed: type IV (20%), with a single tendon inserting distally to the fascia covering the fourth interosseous space; type I (18%), with a single tendon inserting distally onto the shaft of the fifth metatarsal bone; type V (14%), with a bifurcated arrangement comprising a main tendon characterised by a very wide insertion onto the base of the fifth metatarsal bone and an accessory band inserting onto the base of the fourth metatarsal bone; and type III (12%) with a single tendon inserting distally onto the shaft of the fourth metatarsal bone and fascia covering the fourth interosseous space. Finally, type II (4%) was characterised by a single tendon inserting onto the base of the fifth metatarsal bone via a very wide distal insertion. CONCLUSIONS: The FT demonstrates high morphological variability, with the most common configuration found in adults - a single insertion onto metatarsal 5 - being actually uncommonly found in foetuses.


Assuntos
Músculo Esquelético , Tendões , Adulto , Cadáver , Feminino , Feto , Humanos , Perna (Membro)/anatomia & histologia , Masculino , Músculo Esquelético/anatomia & histologia , Tendões/anatomia & histologia
10.
Strahlenther Onkol ; 198(1): 66-72, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34476532

RESUMO

PURPOSE: This retrospective analysis aims to address the toxicity and efficacy of a modified total nodal irradiation (TNI)-based conditioning regimen before haploidentical hematopoietic cell transplantation (HCT) in pediatric patients. MATERIALS AND METHODS: Patient data including long-term follow-up were evaluated of 7 pediatric patients with malignant (n = 2) and non-malignant diseases (n = 5) who were treated by a primary TNI-based conditioning regimen. TNI was performed using anterior/posterior opposing fields. All patients received 7 Gy single-dose TNI combined with systemic agents followed by an infusion of peripheral blood stem cells (n = 7). All children had haploidentical family donors. RESULTS: Engraftment was reached in 6/7 children after a median time of 9.5 days; 1 child had primary graft failure but was successfully reconditioned shortly thereafter. After an average follow-up time of 103.5 months (range 8.8-138.5 months), event-free (EFS) and overall survival (OS) rates were 71.4% and 85.7%, respectively. One child with a non-malignant disease died 8.8 months after transplantation due to a relapse and a multiple organ failure. Follow-up data was available for 5/6 long-term survivors with a median follow-up (FU) of 106.2 months (range 54.5-138.5 months). Hypothyroidism and deficiency of sexual hormones was present in 3/5 patients each. Mean forced expiratory volume in 1 s (FEV1) after TNI was 71%; mean vital capacity (VC) was 78%. Growth failure (< 10th percentile) occurred in 2/5 patients (height) and 1/5 patient (weight). No secondary malignancies were reported. CONCLUSION: In this group of patients, a primary single-dose 7 Gy TNI-based conditioning regimen before HCT in pediatric patients allowed sustained engraftment combined with a tolerable toxicity profile leading to long-term OS/EFS. Late toxicity after a median FU of over 9 years includes growth failure, manageable hormonal deficiencies, and acceptable decrease in lung function.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Criança , Doença Enxerto-Hospedeiro/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Recidiva Local de Neoplasia/etiologia , Estudos Retrospectivos , Condicionamento Pré-Transplante/efeitos adversos
11.
Folia Morphol (Warsz) ; 80(3): 707-713, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32844391

RESUMO

The coracobrachialis longus muscle (CBL) is an extremely rare variant of the coracobrachialis muscle (CRM). The CBL originates from the apex of the coracoid process together with the short head of the biceps brachii and inserts on the olecranon of the ulna. The CBL consists of three parts: a superior part (classical CRM - length 137.88 mm), a middle fibrous layer (23.41 mm), and an inferior part (185.37 mm). A rare relationship between the CBL and median, musculocutaneous and ulnar nerves was observed with potential compression at these three parts. In addition, this case report describes a connection between CBL and the medial head of the triceps brachii, as well as a third head of the biceps brachii, which originate from the fibrous layer. This case report highlights the relationships between the CBL and the median, ulnar and musculocutaneous nerves.


Assuntos
Articulação do Cotovelo , Nervo Ulnar , Braço , Cadáver , Humanos , Músculo Esquelético , Nervo Musculocutâneo/anatomia & histologia
12.
Ophthalmologe ; 118(4): 337-344, 2021 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-32638094

RESUMO

The Sicca-Förderpreis (Dry Eye Award) supports the development of scientific research on the pathogenesis, diagnostics, and treatment of dry eye and ocular surface diseases. It is awarded after a limited call for proposals in German-speaking countries, written application and selection of the award winner after evaluation by a jury of ophthalmologists working in basic and clinical science. In this article examples of the results of funded projects of the Sicca-Förderpreis 2016 are cursorily described, which were presented at the Ophthalmological Academy of Germany 2019 (Augenärztliche Akademie Deutschland 2019) and therefore provide an insight into current scientific developments. The role of muscarinic receptors and those of urea in the pathogenesis of dry eye as well as the (missing) correlation of tear film stability, viscosity and surface tension are highlighted. A project on the early detection of ocular involvement in graft versus host disease and the idea of treating meibomian gland dysfunction with eyelid surgery techniques are also groundbreaking. The outlined projects represent the potential for further substantial developments in the understanding, diagnostics and treatment of dry eye; however, their long-term clinical relevance still needs to be established.


Assuntos
Distinções e Prêmios , Síndromes do Olho Seco , Doenças Palpebrais , Síndromes do Olho Seco/diagnóstico , Síndromes do Olho Seco/terapia , Alemanha , Humanos , Glândulas Tarsais , Lágrimas
13.
Acta Biomater ; 118: 113-128, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33080391

RESUMO

The mechanical behavior of cartilage tissue plays a crucial role in physiological mechanotransduction processes of chondrocytes and pathological changes like osteoarthritis. Therefore, intensive research activities focus on the identification of implant substitute materials that mechanically mimic the cartilage extracellular matrix. This, however, requires a thorough understanding of the complex mechanical behavior of both native cartilage and potential substitute materials to treat cartilage lesions. Here, we perform complex multi-modal mechanical analyses of human articular cartilage and two surrogate materials, commercially available ChondroFillerliquid, and oxidized alginate-gelatin (ADA-GEL) hydrogels. We show that all materials exhibit nonlinearity and compression-tension asymmetry. However, while hyaline cartilage yields higher stresses in tension than in compression, ChondroFillerliquid and ADA-GEL exhibit the opposite trend. These characteristics can be attributed to the materials' underlying microstructure: Both cartilage and ChondroFillerliquid contain fibrillar components, but the latter constitutes a bi-phasic structure, where the 60% nonfibrillar hydrogel proportion dominates the mechanical response. Of all materials, ChondroFillerliquid shows the most pronounced viscous effects. The present study provides important insights into the microstructure-property relationship of cartilage substitute materials, with vital implications for mechanically-driven material design in cartilage engineering. In addition, we provide a data set to create mechanical simulation models in the future.


Assuntos
Cartilagem Articular , Condrócitos , Humanos , Cartilagem Hialina , Hidrogéis , Mecanotransdução Celular , Engenharia Tecidual
14.
Ann Anat ; 231: 151551, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32512204

RESUMO

Transient receptor potential (TRP) channels are cation channels with ubiquitous expression. Various TRP channels are functionally active at the ocular surface and are involved in tear secretion and multiple inflammatory processes. So far, the impact of TRP channels regarding the development of the lacrimal gland (LG) is unclear. While investigating TRP channels in the LG, the TRPM3 channel presented itself as a promising candidate to play a role in the development and functioning of the LG. Therefore, Trpm3 expression was analyzed in different embryonic and postembryonic LGs. Thus, gene expression of TRPM channels including Trpm2, Trpm3, Trpm4 and Trpm6 was analyzed by quantitative RT-PCR in murine LGs at different developmental stages. Localization of TRPM3 in LGs was examined by immunohistochemistry. Primary LG epithelial cells (LGEC) and mesenchymal cells (MC) from newborn mice were cultured (either separately or collectively) for three days, and Trpm3 expression was analyzed in LGEC and MC. As a result, gene expression of Trpm2, Trpm4 and Trpm6 showed no significant difference in LGs in the different stages of development. However, Trpm3 gene expression was significantly higher in the embryonic stage than in the postnatal stage with the peak at E18. Postnatal, Trpm3 expression significantly decreased up to 28-fold until two years of age. Immunohistochemistry for TRPM3 revealed apical membranous expression in the excretory ducts, as well as in the acini of up to P7 old mice. Trpm3 expression in LGEC were significantly higher than that of MC. Our results indicate that Trpm3 expression in murine LG is age-dependent and peaks at age E18. Its expression is localized in the apical membrane of the glandular epithelium. However, its functional role still requires additional study in the LG.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Aparelho Lacrimal/crescimento & desenvolvimento , Aparelho Lacrimal/metabolismo , Canais de Cátion TRPM/genética , Animais , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Reação em Cadeia da Polimerase em Tempo Real , Canais de Cátion TRPM/metabolismo
15.
Acta Biomater ; 104: 53-65, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31887455

RESUMO

Emerging evidence suggests that the mechanical behavior of the brain plays a critical role in development, disease, and aging. Recent studies have begun to characterize the mechanical behavior of gray and white matter tissue and to identify sets of material models that best reproduce the stress-strain behavior of different brain regions. Yet, these models are mainly phenomenological in nature, their parameters often lack clear physical interpretation, and they fail to correlate the mechanical behavior to the underlying microstructural composition. Here we make a first attempt towards identifying general relations between microstructure and mechanics with the ultimate goal to develop microstructurally motivated constitutive equations for human brain tissue. Using histological staining, we analyze the microstructure of brain specimens from different anatomical regions, the cortex, basal ganglia, corona radiata, and corpus callosum, and identify the regional stiffness and viscosity under multiple loading conditions, simple shear, compression, and tension. Strikingly, our study reveals a negative correlation between cell count and stiffness, a positive correlation between myelin content and stiffness, and a negative correlation between proteoglycan content and stiffness. Additionally, our analysis shows a positive correlation between lipid and proteoglycan content and viscosity. We demonstrate how understanding the microstructural origin of the macroscopic behavior of the brain can help us design microstructure-informed material models for human brain tissue that inherently capture regional heterogeneities. This study represents an important step towards using brain tissue stiffness and viscosity as early diagnostic markers for clinical conditions including chronic traumatic encephalopathy, Alzheimer's and Parkinson's disease, or multiple sclerosis. STATEMENT OF SIGNIFICANCE: The complex and heterogeneous mechanical properties of brain tissue play a critical role for brain function. To understand and predict how brain tissue properties vary in space and time, it will be key to link the mechanical behavior to the underlying microstructural composition. Here we use histological staining to quantify area fractions of microstructural components of mechanically tested specimens and evaluate their individual contributions to the nonlinear macroscopic mechanical response. We further propose a microstructure-informed material model for human brain tissue that inherently captures regional heterogeneities. The current work provides unprecedented insights into the biomechanics of human brain tissue, which are highly relevant to develop refined computational models for brain tissue behavior or to advance neural tissue engineering.


Assuntos
Encéfalo/anatomia & histologia , Modelos Anatômicos , Idoso , Fenômenos Biomecânicos , Elasticidade , Matriz Extracelular/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
16.
Acta Oncol ; 59(2): 149-156, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31559880

RESUMO

Background: We evaluated efficacy and toxicity of 68Ga-PSMA-Positron Emission Tomography/Computed Tomography (PET/CT)-directed stereotactic body radiotherapy and image-guided radiotherapy (SBRT/IGRT) for oligometastases of prostate cancer recurrences after previous surgery.Methods: Nineteen patients were analyzed within a prospective PET-registry study (064/2013BO1) and retrospectively analyzed (807/2017BO2) fulfilling the following inclusion criteria: biochemical recurrence after radical prostatectomy, ≤five 68Ga-PSMA-PET/CT positive lesions. Biochemical control was evaluated with EORTC (European Organization for Research and Treatment of Cancer)- and Phenix-definitions. Toxicity was scored according to CTCAE-criteria v. 4.03.Results: A total of 38 oligometastases (19 patients, 2 with re-treatment) were treated with SBRT/IGRT from October 2014 to July 2017. 68Ga-PSMA-PET/CT-positive lesions were detected on average 39 months (5-139) after prostatectomy (pT2b-3b pN0-1 cM0). Mean PSA (Prostate-specific antigen)-level at time of imaging reached 2.2 ng/mL (range 0.2-10.1). PET/CT-positive lesions were treated with different fractionation schedules reaching biological equivalent doses (BED) of 116.7-230.0 Gy. Concomitant androgen deprivation therapy (ADT) was given in seven patients. After a median follow-up of 17 months (4-42) all patients were alive. Estimated 1-year PSA- control (n = 19) reached 80.8% (Phenix) and 67.5% (EORTC). A PSA-decline (≥50%) was detected in 16/19 patients after radiotherapy. Higher graded G3+-acute toxicity did not occur. Temporary late G3-proctitis was detected in one patient.Conclusions: Reaching of nadir ≤0.1 or 0.2 ng/mL was associated by improved DMFS (distant metastases free survival) and could serve as a surrogate endpoint for RT of oligometastases after initial prostatectomy. Short term effects of 68Ga-PSMA-PET/CT-based ablative radiotherapy for oligometastases demonstrated an acceptable toxicity profile and favorable biochemical response.


Assuntos
Neoplasias da Próstata/patologia , Neoplasias da Próstata/radioterapia , Idoso , Fracionamento da Dose de Radiação , Isótopos de Gálio , Radioisótopos de Gálio , Humanos , Masculino , Glicoproteínas de Membrana/uso terapêutico , Pessoa de Meia-Idade , Metástase Neoplásica , Compostos Organometálicos/uso terapêutico , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Intervalo Livre de Progressão , Estudos Prospectivos , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/mortalidade , Radiocirurgia , Radioterapia Guiada por Imagem , Estudos Retrospectivos
17.
Sci Rep ; 8(1): 13140, 2018 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-30177722

RESUMO

Woundhealing disorders characterized by impaired or delayed re-epithelialization are a serious medical problem that is painful and difficult to treat. Gelsolin (GSN), a known actin modulator, supports epithelial cell regeneration and apoptosis. The aim of this study was to estimate the potential of recombinant gelsolin (rhu-pGSN) for ocular surface regeneration to establish a novel therapy for delayed or complicated wound healing. We analyzed the influence of gelsolin on cell proliferation and wound healing in vitro, in vivo/ex vivo and by gene knockdown. Gelsolin is expressed in all tested tissues of the ocular system as shown by molecular analysis. The concentration of GSN is significantly increased in tear fluid samples of patients with dry eye disease. rhu-pGSN induces cell proliferation and faster wound healing in vitro as well as in vivo/ex vivo. TGF-ß dependent transcription of SMA is significantly decreased after GSN gene knockdown. Gelsolin is an inherent protein of the ocular system and is secreted into the tear fluid. Our results show a positive effect on corneal cell proliferation and wound healing. Furthermore, GSN regulates the synthesis of SMA in myofibroblasts, which establishes GSN as a key protein of TGF-ß dependent cell differentiation.


Assuntos
Túnica Conjuntiva/metabolismo , Córnea/metabolismo , Síndromes do Olho Seco/genética , Gelsolina/genética , Reepitelização/genética , Actinas/genética , Actinas/metabolismo , Animais , Diferenciação Celular , Proliferação de Células , Túnica Conjuntiva/patologia , Córnea/patologia , Síndromes do Olho Seco/sangue , Síndromes do Olho Seco/patologia , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Pálpebras/citologia , Pálpebras/metabolismo , Feminino , Gelsolina/sangue , Regulação da Expressão Gênica , Humanos , Aparelho Lacrimal/metabolismo , Aparelho Lacrimal/patologia , Masculino , Camundongos , Miofibroblastos/citologia , Ducto Nasolacrimal/citologia , Ducto Nasolacrimal/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Cicatrização/genética
18.
Neuropathol Appl Neurobiol ; 44(2): 207-223, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29053887

RESUMO

AIMS: Previous data suggest that expression of transcription factors FoxG1 and Olig-2 can separate hotspot histone H3 family member 3A (H3F3A)-mutant tumours in paediatric glioma. We evaluated their prognostic potential and feasibility for identifying H3F3A-mutant tumours among IDH-mutant/wild-type gliomas. METHODS: Immunohistochemistry of FoxG1/Olig-2 and α-thalassaemia/mental-retardation-syndrome-X-linked gene (ATRX) in 471 cases of diffuse gliomas and molecular determination of IDH, H3F3A, MGMT and 1p/19 codeletion status. RESULTS: Mean percentage of FoxG1-positive tumour cells increased from 17% in WHO grade II to over 21% in grade III to 37% in grade IV tumours, whereas mean Olig-2 indices decreased from 29% to 28% to 17% respectively. FoxG1 indices were similar in astrocytic and oligodendroglial tumours, whereas Olig-2 indices were increased in oligodendrogliomas compared to astrocytic tumours (n = 451, P < 0.0001). FoxG1-positive nuclei were significantly reduced in IDH and H3F3A K27-mutant tumours, whereas Olig-2-positive nuclei were significantly reduced in IDH-wild-type and H3F3A G34-mutant tumours. Among IDH-mutant tumours, mean Olig-2 index was significantly higher in 1p/19q codeleted tumours (mean: 43%) compared to IDH-mutant tumours with ATRX loss (mean: 23%, P < 0.0001). A significantly better outcome was first suggested for FoxG1low tumours (n = 212, log rank P = 0.0132) and Olig-2high tumours (n = 203, log-rank P = 0.0011) based on classification and regression tree determined cutoffs, but this was not confirmed by multivariate analysis including IDH mutation, WHO grade, ATRX status and age. CONCLUSIONS: While the combined FoxG1/Olig-2 profile may discriminate H3F3A K27- and G34-mutant tumours and define a prognostically favourable subset in IDH-mutant gliomas, our data show that labelling indices of these transcription factors overlap with adult IDH-mutant and wild-type tumour classes.


Assuntos
Neoplasias Encefálicas/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Glioma/metabolismo , Isocitrato Desidrogenase/genética , Proteínas do Tecido Nervoso/metabolismo , Fator de Transcrição 2 de Oligodendrócitos/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Criança , Feminino , Fatores de Transcrição Forkhead/genética , Glioma/genética , Glioma/mortalidade , Glioma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Proteínas do Tecido Nervoso/genética , Fator de Transcrição 2 de Oligodendrócitos/genética , Prognóstico , Taxa de Sobrevida , Adulto Jovem
20.
Ann Anat ; 211: 135-139, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28279730

RESUMO

INTRODUCTION: Pathological formation of blood vessels plays a key role in the growth and metastasis of tumors and also in several serious ophthalmological diseases such as wet age-related macular degeneration (AMD) or diabetic retinopathy. In AMD treatment, aflibercept (tradename EYLEA®) is used to deactivate the underlying pathological neovascularisation. Aflibercept is a recombinant fusion protein which binds to vascular endothelial growth factor (VEGF) receptors, thereby inhibiting VEGF pathway activation. VEGF is one of the most important angiogenesis factors. OBJECTIVE: This analysis investigates lasting efficacy of aflibercept in vitro for later application as therapeutic agent against macular degeneration (AMD). MATERIAL AND METHODS: VEGF-ELISA assays were performed to investigate binding affinities at different aflibercept concentrations. The impact of VEGF on the proliferation of human umbilical vein endothelial cells (HUVEC) was investigated using proliferation assays. Moreover, time-dependent kinetic studies were performed to analyze different aflibercept storage durations with regard to its inhibitory capabilities on human VEGF. RESULTS AND CONCLUSION: Our results reveal that aflibercept significantly lowers the amount of unbound VEGF as well as the proliferation rate of HUVEC. Moreover, in contrast to specifications given by the manufacturer, aflibercept retains its full inhibitory effect up to at least 120h after transference from the original vial into the injection syringe.


Assuntos
Proliferação de Células/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/fisiologia , Receptores de Fatores de Crescimento do Endotélio Vascular/administração & dosagem , Proteínas Recombinantes de Fusão/administração & dosagem , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/metabolismo , Inibidores da Angiogênese/administração & dosagem , Linhagem Celular , Proliferação de Células/fisiologia , Relação Dose-Resposta a Droga , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Humanos
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