Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 23
Filtrar
1.
Pharm Res ; 41(3): 567-576, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38351229

RESUMO

PURPOSE: This study investigates in silico the contribution of the hair follicle to the overall dermal permeability of small molecules, as published experimental work provides inconclusive information on whether the follicular route favours the permeation of hydrophobic or hydrophilic permeants. METHOD: A study is conducted varying physico-chemical parameters of permeants such as lipophilicity, molecular weight and protein binding. The simulated data is compared to published experimental data to discuss how those properties can modulate the contribution of the hair follicle to the overall dermal permeation. RESULTS: The results indicate that the contribution of the follicular route to dermal permeation can range from negligible to notable depending on the combination of lipophilic/hydrophilic properties of the substance filling the follicular route and the permeant. CONCLUSION: Characterisation of the substance filling the follicular route is required for analysing the experimental data of dermal permeation of small molecules, as changes between in vivo and in vitro due to handling of samples and cessation of vital functions can modify the contribution of the follicular route to overall dermal permeation, hence hindering data interpretation.


Assuntos
Folículo Piloso , Absorção Cutânea , Folículo Piloso/metabolismo , Permeabilidade , Interações Hidrofóbicas e Hidrofílicas , Pele/metabolismo
2.
Morphologie ; 108(361): 100757, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38134867

RESUMO

Voice disorders are common among teachers and, in particular, anatomy teachers are exposed to a potential enemy for dysphonia, irritating chemicals, that is, formaldehyde. We seek to verify the association between: (1) teaching time, (2) type of cadaveric conservation to which the teacher is exposed and (3) hours of exposure to cadaveric preservative related to the different categories of voice disorders screening (ITDV). The sample consisted of 111 teachers who answered to 02 data collection instruments: I - Sociodemographic Data; II - ITDV. Among participating teachers there were 71 male and 40 female, with an average age of 43 years and 11 months and an average teaching time of 16 years and 5 months. Association tests between teaching time and ITDV demonstrate a significant result in the relationship between voice failure and teaching time (p<0.05). All 111 teachers use their voices in laboratory classes and use cadaveric material. From those, 107 teachers are exposed to formaldehyde as cadaveric parts' conservative solution. There was a significant association (p<0.05) between voice failure and the type of cadaveric conservative solution but non-significant relationship (p>0.05) between ITDV and the time of exposure to formaldehyde preservative. Teachers' ITDV showed vocal signs and symptoms. In particular, voice loss due to time of teaching in anatomy, and voice failure, due to exposure to formaldehyde and combinations used in anatomical parts and cadavers, were significant.

3.
Medicina (Ribeirao Preto, Online) ; 56(3)nov. 2023. ilus, tab
Artigo em Português | LILACS | ID: biblio-1551372

RESUMO

Os termos médicos utilizados na morfologia eram provenientes de um nome próprio, com o intuito de homenagear os que descobriram ou apresentaram a estrutura anatômica, conhecidos como epônimos. Buscando unificar a linguagem anatômica e facilitar o processo de ensino, em 1989 foi criado o Comitê Federativo Internacional de Terminologia Anatômica (FICAT), cujo propósito era revisar os epônimos e atualizar a terminologia anatômica. Com o objetivo de apresentar os fundamentos e conhecimentos sobre a origem das terminologias anatômicas nas mídias sociais, a Liga Acadêmica de Anatomia da Universidade Federal de Alfenas (LAANAT/UNIFAL-MG), por meio do projeto de extensão "Anatomia de A a Z", divulgou conhecimentos científicos acerca da etimologia anatômica. Foram feitas postagens semanais no Instagram e no Facebook, a partir de publicações elaboradas pelos ligantes, supervisionadas pelos professores coordenadores e desenvolvidas no aplicativo Canva. Cada postagem seguiu sequen-cialmente as letras do alfabeto (de A a Z) e eram compostas da etimologia de duas estruturas anatômicas. Frente a uma análise de dados, observamos que em 23 publicações, alcançamos 712 curtidas, 194 compartilhamentos, 44 publicações salvas, 4739 contas alcançadas e 6608 impressões. A LAANAT promoveu, de forma clara e objetiva, a divulgação de conhecimentos das terminologias anatômicas ao público geral (AU).


The medical terms used in morphology were derived from proper nouns to honor those who discovered or presented the anatomical structure, known as eponyms. In 1989, anatomists founded the Federative International Program on Anatomical Terminologies (FICAT) to unify anatomical language and facilitate the teaching process by reviewing eponyms and updating nomenclature. Intending to present the fundamentals and knowledge about the origin of anatomical terminologies on social media, the Academic League of Anatomy at the Federal University of Alfenas (LAANAT/UNIFAL-MG), through the extension project "Anatomy from A to Z" disseminated scientific knowledge about anatomical etymology. Weekly posts were made on Instagram and Facebook, based on publications elaborated by the League members, supervised by the professors, and developed on the Canva application. Each post sequentially followed the letters of the alphabet (from A to Z) and consisted of the etymology of two anatomical structures. In analyzing the data, we observed that in 23 publications, we achieved 712 likes, 194 shares, 44 saved posts, 4739 reached accounts, and 6608 prints. LAANAT promoted, clearly and objectively, the dissemination of knowledge of anatomical terminologies to the general public


Assuntos
Epônimos , Medicina , Terminologia como Assunto
4.
J Oral Biol Craniofac Res ; 13(5): 636-641, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37637855

RESUMO

Background and aim: The temporomandibular joint (TMJ) is a synovial joint that allows the complex movements essential for life. It connects the jawbone to the skull, working as a sliding hinge. Moreover, pluripotent stem cells are a source of precursors and tissue-specific cells in developing organisms, however, their biodistribution in developing fetal tissues is weakly studied. The aim of our study was analyse immunohistochemical expression of Nanog, Oct-4, Sox-2 and Stat-3 and Sox-5, in TMJ tissue samples from human fetuses aged between the 12th and 20th weeks of intrauterine life. Materials and methods: We fixed and processed TMJ tissue samples from human fetuses, histological sections and immunohistochemical procedures were carried out. Results: TMJ histological studies examination did not reveal any difference in the tissue organization between the samples in the studied periods. Immunohistochemical analysis demonstrated that Oct-4 and Sox-2 lack their expression in TMJ. In contrast, Nanog was expressed in nucleous of proliferative layer of mandibular condyle, Stat-3 was expressed in nuclear cells of articular disc, Stat-3 and Sox-5 showed positive nuclear and cytoplasmic immunostaining in codrocyte layers and in ossification areas. Conclusions: Nanog acts in maintanence of pluripotency, Stat-3 in articular disc acts as a transcriptional factor. Stat-3 and Sox-2 act in chondrocyte and osteoblast diferentiation. Distribution of the cells, which express Nanog, Stat-3, and Sox-5 in TMJ tissue during fetal development, can help further understand its physiology, pathology, and repairing capacities.

5.
Pharm Res ; 40(1): 295-305, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36348132

RESUMO

OBJECTIVES: To develop a simulation model to explore the interplay between mechanical stretch and diffusion of large molecules into the skin under locally applied hypobaric pressure, a novel penetration enhancement method. METHODS: Finite element method was used to model the skin mechanical deformation and molecular diffusion processes, with validation against in-vitro transdermal permeation experiments. Simulations and experimental data were used together to investigate the transdermal permeation of large molecules under local hypobaric pressure. RESULTS: Mechanical simulations resulted in skin stretching and thinning (20%-26% hair follicle diameter increase, and 21%-27% skin thickness reduction). Concentration of dextrans in the stratum corneum was below detection limit with and without hypobaric pressure. Concentrations in viable epidermis and dermis were not affected by hypobaric pressure (approximately 2 µg [Formula: see text] cm-2). Permeation into the receptor fluid was substantially enhanced from below the detection limit at atmospheric pressure to up to 6 µg [Formula: see text] cm-2 under hypobaric pressure. The in-silico simulations compared satisfactorily with the experimental results at atmospheric conditions. Under hypobaric pressure, satisfactory comparison was attained when the diffusion coefficients of dextrans in the skin layers were increased from [Formula: see text] 10 µm2 [Formula: see text] s-1 to between 200-500 µm2 [Formula: see text] s-1. CONCLUSIONS: Application of hypobaric pressure induces skin mechanical stretching and enlarges the hair follicle. This enlargement alone cannot satisfactorily explain the increased transdermal permeation into the receptor fluid under hypobaric pressure. The results from the in-silico simulations suggest that the application of hypobaric pressure increases diffusion in the skin, which leads to improved overall transdermal permeation.


Assuntos
Dextranos , Pele , Preparações Farmacêuticas , Administração Cutânea , Epiderme
6.
Arq. ciências saúde UNIPAR ; 27(9): 5142-5162, 2023.
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1510199

RESUMO

A Terapia Cognitiva Baseada em Mindfulness (MBCT, do inglês Mindfulness-Based Cognitive Therapy) é uma técnica baseada na combinação da Terapia Cognitiva-Comportamental e da meditação mindfulness, na busca pela melhoria de sintomas psiquiátricos. O presente trabalho tem como objetivo a busca por publicações que discutam as implicações neurológicas de pacientes diagnosticados com transtorno depressivo e transtorno de ansiedade e que buscaram nessa técnica a melhoria de sua condição clínica ou qualidade de vida. Nossos resultados preliminares mostraram que os benefícios dessa prática foram colhidos na totalidade dos estudos encontrados, elucidando as áreas cerebrais modificadas e o motivo pelo qual elas foram ativadas. Procuramos abordar ainda a diferença entre essa técnica e o uso de medicamentos e tratamento usual. PALAVRAS-CHAVE: Terapia Cognitiva-Comportamental; Cérebro; Transtornos Psiquiátricos; Antidepressivos.


Mindfulness-Based Cognitive Therapy (MBCT) is a technique based on the combination of Cognitive-Behavioral Therapy and mindfulness meditation, in the search of improving psychiatric symptoms. This present work aims to search for studies and articles that discuss the neurological implications of patients diagnosed with anxiety and major depressive disorders who sought improvement in their clinical condition or life quality through this technique. The preliminary results showed that the benefits of this practice were observed in all of the studies found, elucidating the modified brain areas and the reason why they were activated. The differences between this technique and the use of medication and treatment-as-usual was also addressed.


La Terapia Cognitiva Basada en Mindfulness (MBCT) es una técnica basada en la combinación de la Terapia Cognitivo-Conductual y la meditación mindfulness, en la búsqueda de la mejora de los síntomas psiquiátricos. El presente trabajo tiene como objetivo buscar publicaciones que discutan las implicaciones neurológicas de pacientes diagnosticados con trastorno depresivo y trastorno de ansiedad y que busquen en esta técnica mejorar su condición clínica o calidad de vida. Nuestros resultados preliminares mostraron que los beneficios de esta práctica se cosecharon en todos los estudios encontrados, dilucidando las áreas cerebrales modificadas y la razón por la cual se activaron. También tratamos de abordar la diferencia entre esta técnica y el uso de medicación y tratamiento habitual.

7.
Journal of Oral Biology and Craniofacial Research, v. 13, n. 1, 636-641, out. 2023
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-5097

RESUMO

The temporomandibular joint (TMJ) is a synovial joint that allows the complex movements essential for life. It connects the jawbone to the skull, working as a sliding hinge. Moreover, pluripotent stem cells are a source of precursors and tissue-specific cells in developing organisms, however, their biodistribution in developing fetal tissues is weakly studied. The aim of our study was analyse immunohistochemical expression of Nanog, Oct-4, Sox-2 and Stat-3 and Sox-5, in TMJ tissue samples from human fetuses aged between the 12th and 20th weeks of intrauterine life.

8.
Proc Natl Acad Sci U S A ; 119(18): e2120340119, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35482922

RESUMO

Advanced therapies are commonly administered via injection even when they act within the skin tissue, and this increases the chances of off-target effects. Here we report the use of a skin patch containing a hypobaric chamber that induces skin dome formation to enable needleless delivery of advanced therapies directly into porcine, rat, and mouse skin. Finite element method modeling showed that the hypobaric chamber in the patch opened the skin appendages by 32%, thinned the skin, and compressed the appendage wall epithelia. These changes allowed direct delivery of an H1N1 vaccine antigen and a diclofenac nanotherapeutic into the skin. Fluorescence imaging and infrared mapping of the skin showed needleless delivery via the appendages. The in vivo utility of the patch was demonstrated by a superior immunoglobulin G response to the vaccine antigen in mice compared to intramuscular injection and a 70% reduction in rat paw swelling in vivo over 5 h with diclofenac without skin histology changes.


Assuntos
Pele , Vacinas , Administração Cutânea , Animais , Camundongos , Agulhas , Ratos , Pele/metabolismo , Absorção Cutânea , Suínos
9.
Waste Manag ; 137: 81-88, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34749180

RESUMO

In this work, the use of biomethane produced from local biogas plants is proposed as renewable fuel for light marine transport. A profitability analysis is performed for three real biogas production plants located in Cornwall (United Kingdom), considering a total of 66 different scenarios where critical parameters such as distance from production point to gas grid, subsidies, etcetera, were evaluated. Even though the idea is promising to decarbonize the marine transport sector, under the current conditions, the approach is not profitable. The results show that profitability depends on the size of the biogas plant. The largest biogas plant studied can be profitable if feed-in tariffs subsidies between 36.6 and 45.7 €/MWh are reached, while for the smallest plant, subsidies should range between 65 and 82.7 €/MWh. The tax to be paid per ton of CO2 emitted by the shipping owner, was also examined given its impact in this green route profitability. Values seven times greater than current taxes are needed to reach profitability, revealing the lack of competitiveness of renewable fuels vs traditional fuels in this application. Subsidies to make up a percentage of the investment are also proposed, revealing that even at 100% of investment subsidized, this green approach is still not profitable. The results highlight the need for further ambitious political actions in the pursuit of sustainable societies.


Assuntos
Biocombustíveis , Metano , Reino Unido
10.
Skin Res Technol ; 27(5): 948-958, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33822382

RESUMO

BACKGROUND: Suction cups are widely used in applications such as in measurement of mechanical properties of skin in vivo, in drug delivery devices or in acupuncture treatment. Understanding mechanical response of skin under hypobaric pressure is of great importance for users of suction cups. The aim of this work is to predict the hypobaric pressure induced 3D stretching of the skin. METHODS: Experimental skin tensile tests were carried out for mechanical property characterization. Both linear elasticity and hyperelasticity parameters were determined and implemented in Finite Element modelling. Skin suction tests were performed in both experiments and FEM simulations for model validation. 3D skin stretching is then visualized in detail in FEM simulations. RESULTS: The simulations showed that the skin was compressed consistently along the thickness direction, leading to reduced thickness. At the center of the dome, the radial and angular strain decreases from the top surface to the bottom surface, although always in tension. Hyperelasticity modelling showed superiority over linear elasticity modelling while predicting the strain distribution because the stretch ratio reaches values exceeding the initial linear elastic stage of the stress-strain curve for skin. CONCLUSION: Hyperelasticity modelling is an effective approach to predict the 3D strain distribution, which paves a way to accurately design safe commercial products that interface with the skin.


Assuntos
Pele , Fenômenos Biomecânicos , Elasticidade , Análise de Elementos Finitos , Pressão , Estresse Mecânico
11.
Antioxidants (Basel) ; 9(12)2020 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-33287170

RESUMO

Chlamydia trachomatis (Ct) is a bacterial intracellular pathogen responsible for a plethora of diseases ranging from blindness to pelvic inflammatory diseases and cervical cancer. Although this disease is effectively treated with antibiotics, concerns for development of resistance prompt the need for new low-cost treatments. Here we report the activity of spilanthol (SPL), a natural compound with demonstrated anti-inflammatory properties, against Ct infections. Using chemical probes selective for imaging mitochondrial protein sulfenylation and complementary assays, we identify an increase in mitochondrial oxidative state by SPL as the underlying mechanism leading to disruption of host cell F-actin cytoskeletal organization and inhibition of chlamydial infection. The peroxidation product of SPL (SPL endoperoxide, SPLE), envisioned to be the active compound in the cellular milieu, was chemically synthesized and showed more potent anti-chlamydial activity. Comparison of SPL and SPLE reactivity with mammalian peroxiredoxins, demonstrated preferred reactivity of SPLE with Prx3, and virtual lack of SPL reaction with any of the reduced Prx isoforms investigated. Cumulatively, these findings support the function of SPL as a pro-drug, which is converted to SPLE in the cellular milieu leading to inhibition of Prx3, increased mitochondrial oxidation and disruption of F-actin network, and inhibition of Ct infection.

12.
Cell Transplant ; 28(12): 1573-1584, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31462071

RESUMO

Facial paralysis can result in severe implications for the patients. However, stem cell biology has become an important field in regenerative medicine since the discovery and characterization of mesenchymal stem cells. Our aim was to evaluate the regeneration after facial nerve crush injury and application of human immature dental pulp stem cells (iDPSC). For this study 70 Wistar rats underwent a unilateral facial nerve crush injury and were divided into two groups: Group I (GI): Crushed; Group II (GII): Crushed and iDPSC, and distributed into study periods of 3, 7, 14, 21, and 42 postoperative days. Facial nerve regeneration was analyzed via functional recovery of whisker movement, histomorphometric analysis, and immunoblotting assay. The results show that GII had complete functional recovery at 14 days, while GI recovered after 42 days. Also, regarding the facial nerve trunk, GII presented histological improvement, evidencing better axonal and structural organization of the myelin sheath, and exhibited statistically higher values for the outer and inner perimeters and g-ratio. Nevertheless, GI exhibited statistically higher values for the thickness of myelin sheath. In the buccal branch, no differences were observed for all parameters between groups. At 42 days, both groups GI and GII were close to the levels observed for the control group. Concerning nerve growth factor expression, GII exhibited statistically greater values (p < 0.05) compared with the control group at 7 days. In summary, a single injection of human iDPSC promoted a positive effect on regeneration of the facial nerve trunk after 14 days and provided an alternative to support regeneration following peripheral nerve injury.


Assuntos
Polpa Dentária/metabolismo , Traumatismos do Nervo Facial , Nervo Facial , Regeneração Nervosa , Transplante de Células-Tronco , Células-Tronco/metabolismo , Animais , Polpa Dentária/patologia , Nervo Facial/patologia , Nervo Facial/fisiologia , Traumatismos do Nervo Facial/metabolismo , Traumatismos do Nervo Facial/patologia , Traumatismos do Nervo Facial/terapia , Xenoenxertos , Humanos , Ratos , Ratos Wistar , Células-Tronco/patologia
13.
Protein Sci ; 28(1): 216-227, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30367535

RESUMO

Sulforaphane (SFN), a phytochemical found in broccoli and other cruciferous vegetables, is a potent antioxidant and anti-inflammatory agent with reported effects in cancer chemoprevention and suppression of infection with intracellular pathogens. Here we report on the impact of SFN on infection with Chlamydia trachomatis (Ct), a common sexually transmitted pathogen responsible for 131 million new cases annually worldwide. Astoundingly, we find that SFN as well as broccoli sprouts extract (BSE) promote Ct infection of human host cells. Both the number and size of Ct inclusions were increased when host cells were pretreated with SFN or BSE. The initial investigations presented here point to both the antioxidant and thiol alkylating properties of SFN as regulators of Ct infection. SFN decreased mitochondrial protein sulfenylation and promoted Ct development, which were both reversed by treatment with mitochondria-targeted paraquat (MitoPQ). Inhibition of the complement component 3 (complement C3) by SFN was also identified as a mechanism by which SFN promotes Ct infections. Mass spectrometry analysis found alkylation of cysteine 1010 (Cys1010) in complement C3 by SFN. The studies reported here raise awareness of the Ct infection promoting activity of SFN, and also identify potential mechanisms underlying this activity.


Assuntos
Infecções por Chlamydia/metabolismo , Chlamydia trachomatis/metabolismo , Ativação do Complemento/efeitos dos fármacos , Complemento C3/metabolismo , Isotiocianatos/farmacologia , Proteínas Mitocondriais/metabolismo , Infecções por Chlamydia/patologia , Células HeLa , Humanos , Oxirredução/efeitos dos fármacos , Sulfóxidos
14.
Cell Transplant. ; 28(12): 1573-1584, 2019.
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib17652

RESUMO

Facial paralysis can result in severe implications for the patients. However, stem cell biology has become an important field in regenerative medicine since the discovery and characterization of mesenchymal stem cells. Our aim was to evaluate the regeneration after facial nerve crush injury and application of human immature dental pulp stem cells (iDPSC). For this study 70 Wistar rats underwent a unilateral facial nerve crush injury and were divided into two groups: Group I (GI): Crushed; Group II (GII): Crushed and iDPSC, and distributed into study periods of 3, 7, 14, 21, and 42 postoperative days. Facial nerve regeneration was analyzed via functional recovery of whisker movement, histomorphometric analysis, and immunoblotting assay. The results show that GII had complete functional recovery at 14 days, while GI recovered after 42 days. Also, regarding the facial nerve trunk, GII presented histological improvement, evidencing better axonal and structural organization of the myelin sheath, and exhibited statistically higher values for the outer and inner perimeters and g-ratio. Nevertheless, GI exhibited statistically higher values for the thickness of myelin sheath. In the buccal branch, no differences were observed for all parameters between groups. At 42 days, both groups GI and GII were close to the levels observed for the control group. Concerning nerve growth factor expression, GII exhibited statistically greater values (p < 0.05) compared with the control group at 7 days. In summary, a single injection of human iDPSC promoted a positive effect on regeneration of the facial nerve trunk after 14 days and provided an alternative to support regeneration following peripheral nerve injury.

15.
Cell Transplant, v. 28, n. 12, p. 1573-1584, ago. 2019
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-3029

RESUMO

Facial paralysis can result in severe implications for the patients. However, stem cell biology has become an important field in regenerative medicine since the discovery and characterization of mesenchymal stem cells. Our aim was to evaluate the regeneration after facial nerve crush injury and application of human immature dental pulp stem cells (iDPSC). For this study 70 Wistar rats underwent a unilateral facial nerve crush injury and were divided into two groups: Group I (GI): Crushed; Group II (GII): Crushed and iDPSC, and distributed into study periods of 3, 7, 14, 21, and 42 postoperative days. Facial nerve regeneration was analyzed via functional recovery of whisker movement, histomorphometric analysis, and immunoblotting assay. The results show that GII had complete functional recovery at 14 days, while GI recovered after 42 days. Also, regarding the facial nerve trunk, GII presented histological improvement, evidencing better axonal and structural organization of the myelin sheath, and exhibited statistically higher values for the outer and inner perimeters and g-ratio. Nevertheless, GI exhibited statistically higher values for the thickness of myelin sheath. In the buccal branch, no differences were observed for all parameters between groups. At 42 days, both groups GI and GII were close to the levels observed for the control group. Concerning nerve growth factor expression, GII exhibited statistically greater values (p < 0.05) compared with the control group at 7 days. In summary, a single injection of human iDPSC promoted a positive effect on regeneration of the facial nerve trunk after 14 days and provided an alternative to support regeneration following peripheral nerve injury.

16.
Matrix Biol ; 64: 81-93, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28882761

RESUMO

The small leucine-rich proteoglycans (SLRPs), decorin and biglycan, are key regulators of collagen fibril and matrix assembly. The goal of this work was to elucidate the roles of decorin and biglycan in tendon homeostasis. Our central hypothesis is that decorin and biglycan expression in the mature tendon would be critical for the maintenance of the structural and mechanical properties of healthy tendons. Defining the function(s) of these SLRPs in tendon homeostasis requires that effects in the mature tendon be isolated from their influence on development. Thus, we generated an inducible knockout mouse model that permits genetic ablation of decorin and biglycan expression in the mature tendon, while maintaining normal expression during development. Decorin and biglycan expression were knocked out in the mature patellar tendon with the subsequent turnover of endogenous SLRPs deposited prior to induction. The acute absence of SLRP expression was associated with changes in fibril structure with a general shift to larger diameter fibrils in the compound knockout tendons, together with fibril diameter heterogeneity. In addition, tendon mechanical properties were altered. Compared to wild-type controls, acute ablation of both genes resulted in failure of the tendon at lower loads, decreased stiffness, a trend towards decreased dynamic modulus, as well as a significant increase in percent relaxation and tissue viscosity. Collagen fiber realignment was also increased with a delayed and slower in response to load in the absence of expression. These structural and functional changes in response to an acute loss of decorin and biglycan expression in the mature tendon demonstrate a significant role for these SLRPs in adult tendon homeostasis.


Assuntos
Biglicano/genética , Colágeno/química , Decorina/genética , Ligamento Patelar/fisiopatologia , Animais , Biglicano/metabolismo , Fenômenos Biomecânicos , Decorina/metabolismo , Técnicas de Inativação de Genes , Homeostase , Camundongos
17.
Photomed Laser Surg ; 35(8): 408-414, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28358662

RESUMO

OBJECTIVE: Assess morphologically the efficacy of constant dose (CD) or gradual dose (GD) in photobiomodulation therapy (PBMT) during the regeneration process of rats' mental nerve after compression lesion. MATERIALS AND METHODS: Forty-eight male Wistar rats were used and divided into four groups (n = 12): negative control (NC): lesion by compression; positive control (PC): no lesion; GD: lesion by compression and PBMT with GD; and CD: lesion by compression and PBMT with CD. One day after the surgery, the groups GD and CD underwent PBMT daily in three equidistant points around the incision area. The parameters were wavelength of 808 nm, 100 mW, CD received treatment with 120 J/cm2, while GD underwent the protocol of application: 1st and 4th sessions: 80 J/cm2; 5th to 8th sessions: 90 J/cm2; 9th to 12th sessions: 100 J/cm2; 13th to 16th sessions: 110 J/cm2; and 17th to 20th sessions: 120 J/cm2. Euthanasias were performed at 3, 7, 14, and 21 days. Qualitative and quantitative analysis of the mental nerves were performed with ANOVA (analysis of variance) and Tukey tests (p ≤ 0.05). RESULTS: It was observed that PBMT was able to accelerate the process of nerve regeneration presenting an increase in the number of myelinated fibers starting at 14 days of treatment for groups CD and GD, and at 21 days they were similar to PC. It was observed a better lamellar organization of myelin sheath at 7 days for GD and at 14 days for CD, similar to PC. Both GD and CD presented significant differences compared to NC and PC for thickness of the myelin sheath, outer perimeter, internal area, and number of myelin fibers. CONCLUSIONS: PBMT presented positive effect on the regeneration of nerve starting at 14 days, and after 21 days there was no difference between GD and CD.


Assuntos
Terapia com Luz de Baixa Intensidade/métodos , Regeneração Nervosa/efeitos dos fármacos , Traumatismos do Nervo Trigêmeo/radioterapia , Nervo Trigêmeo/ultraestrutura , Animais , Modelos Animais de Doenças , Relação Dose-Resposta à Radiação , Tomografia com Microscopia Eletrônica , Masculino , Nervo Maxilar , Dosagem Radioterapêutica , Distribuição Aleatória , Ratos , Ratos Wistar , Valores de Referência , Fatores de Tempo , Nervo Trigêmeo/efeitos da radiação , Traumatismos do Nervo Trigêmeo/diagnóstico
18.
Cells Tissues Organs ; 202(5-6): 269-280, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27544531

RESUMO

Adult stem cells research has been considered the most advanced sort of medical-scientific research, particularly stem cells from human exfoliated deciduous teeth (SHED), which represent an immature stem cell population. The purpose of this review is to describe the current knowledge concerning SHED from full-text scientific publications from 2003 to 2015, available in English language and based on the keyword and/or abbreviations 'stem cells from human exfoliated deciduous teeth (SHED)', and individually presented as to the properties of SHED, immunomodulatory properties of SHED and stem cell banking. In summary, these cell populations are easily accessible by noninvasive procedures and can be isolated, cultured and expanded in vitro, successfully differentiated in vitro and in vivo into odontoblasts, osteoblasts, chondrocytes, adipocytes and neural cells, and present low immune reactions or rejection following SHED transplantation. Furthermore, SHED are able to remain undifferentiated and stable after long-term cryopreservation. In conclusion, the high proliferative capacity, easy access, multilineage differentiation capacity, noninvasiveness and few ethical concerns make stem cells from human exfoliated deciduous teeth the most valuable source of stem cells for tissue engineering and cell-based regenerative medicine therapies.


Assuntos
Células-Tronco/citologia , Esfoliação de Dente/patologia , Dente Decíduo/citologia , Separação Celular , Humanos , Fatores Imunológicos , Bancos de Tecidos
19.
Cardiovasc Toxicol ; 12(1): 64-72, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21858600

RESUMO

It has been suggested that prenatal exposure to cadmium may alter the cardiovascular function during adulthood. Using the left coronary artery ligation model of acute myocardial infarction, we studied the cardiac function of female adult offspring rats exposed to cadmium (30 ppm) during gestation. The cardiac ischemic zone in the control and cadmium-exposed groups was measured 72 h post-ligation using the TPT staining technique. Offspring from cadmium-treated dams showed a significantly smaller infarcted area compared with the control group (7.1 ± 1.5 vs. 19.6 ± 2.8%, P ≤ 0.05). We also performed echocardiographic and biochemical studies, which positively correlated with the differences observed previously. To evaluate whether the effects were associated to pre-infarct tissue damage and/or angiogenic molecules, we performed histological studies and measured the expression of vascular endothelial growth factor (VEGF), and platelet endothelial cellular adhesion molecule-1 (PECAM-1). Results revealed a higher heart vascularization in the exposed offspring that was associated with an increase in PECAM and a decrease in VEGF expression. We conclude that prenatal exposure to cadmium induces fetal adaptive responses involving changes in the expression of some cardiac angiogenic molecules resulting in long-term resistance to infarction.


Assuntos
Cádmio/administração & dosagem , Infarto do Miocárdio/patologia , Infarto do Miocárdio/prevenção & controle , Miocárdio/patologia , Animais , Feminino , Infarto do Miocárdio/metabolismo , Miocárdio/metabolismo , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Gravidez , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Efeitos Tardios da Exposição Pré-Natal/patologia , Efeitos Tardios da Exposição Pré-Natal/prevenção & controle , Ratos , Fator A de Crescimento do Endotélio Vascular/metabolismo
20.
Toxicol Appl Pharmacol ; 251(2): 137-45, 2011 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-21236285

RESUMO

Several cardiovascular diseases (CVD) observed in adulthood have been associated with environmental influences during fetal growth. Here, we show that maternal exposure to cadmium, a ubiquitously distributed heavy metal and main component of cigarette smoke is able to induce cardiovascular morpho-functional changes in the offspring at adult age. Heart morphology and vascular reactivity were evaluated in the adult offspring of rats exposed to 30ppm of cadmium during pregnancy. Echocardiographic examination shows altered heart morphology characterized by a concentric left ventricular hypertrophy. Also, we observed a reduced endothelium-dependent reactivity in isolated aortic rings of adult offspring, while endothelium-independent reactivity remained unaltered. These effects were associated with an increase of hem-oxygenase 1 (HO-1) expression in the aortas of adult offspring. The expression of HO-1 was higher in females than males, a finding likely related to the sex-dependent expression of the vascular cell adhesion molecule 1 (VCAM-1), which was lower in the adult female. All these long-term consequences were observed along with normal birth weights and absence of detectable levels of cadmium in fetal and adult tissues of the offspring. In placental tissues however, cadmium levels were detected and correlated with increased NF-κB expression--a transcription factor sensitive to inflammation and oxidative stress--suggesting a placentary mechanism that affect genes related to the development of the cardiovascular system. Our results provide, for the first time, direct experimental evidence supporting that exposure to cadmium during pregnancy reprograms cardiovascular development of the offspring which in turn may conduce to a long term increased risk of CVD.


Assuntos
Cádmio/toxicidade , Exposição Materna/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Sistema Vasomotor/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/fisiologia , Cádmio/administração & dosagem , Feminino , Masculino , Gravidez , Ratos , Ratos Wistar , Sistema Vasomotor/fisiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...