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1.
Neurosurg Clin N Am ; 33(1): 49-59, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34801141

RESUMO

Connective tissue disorders represent a varied spectrum of syndromes that have important implications for the spine deformity surgeon. Spine surgeons must be aware of these diverse and global manifestations of disease because they have significant impact on perioperative and postoperative outcomes.


Assuntos
Tecido Conjuntivo , Coluna Vertebral , Tecido Conjuntivo/cirurgia , Humanos , Coluna Vertebral/cirurgia
2.
Int J Oral Implantol (Berl) ; 14(4): 351-365, 2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34726846

RESUMO

The coronally advanced flap technique is one of the most commonly used approaches for treating gingival recession. Several modifications of the technique have been proposed over the years, making it a highly predictable treatment option for gingival recession; however, as dental implants are structurally and biologically different from natural teeth, a further modification of the conventional coronally advanced flap technique has been suggested to overcome the challenges posed by the treatment of peri-implant soft tissue dehiscences. The present article aims to describe the state of the art of the technique at implant sites presenting with peri-implant soft tissue dehiscences, and highlight the main differences between this and the coronally advanced flap approach in natural teeth. The timing of crown removal and abutment modification/replacement are discussed, along with the different methods for management of the flap and connective tissue graft that are recommended at implant sites. The outcomes of this approach compared to the conventional coronally advanced flap technique, and other approaches are also presented.


Assuntos
Implantes Dentários , Retração Gengival , Tecido Conjuntivo/cirurgia , Coroas , Retração Gengival/cirurgia , Humanos , Retalhos Cirúrgicos
3.
Adv Exp Med Biol ; 1348: 1-3, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34807413

RESUMO

Just like the first edition of this widely successful book the second edition provides latest updates of our understanding of pathophysiology, pathology, clinical presentation and treatment of heritable soft connective tissue diseases. In addition, new knowledge of not only structures but also of functions of basic components of connective tissues (e.g., collagen), and of organs such as tendons has been added as well. Moreover, readers will learn more about new syndromes and new subgroups of previously described syndromes and disorders as well. The authors are not only prominent investigators in their field, but they are also good writers and that should provide an additional incentive for interested readers.


Assuntos
Síndrome de Ehlers-Danlos , Colágeno , Tecido Conjuntivo , Humanos
4.
Adv Exp Med Biol ; 1348: 5-43, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34807414

RESUMO

The physiology of connective tissues like tendons and ligaments is highly dependent upon the collagens and other such extracellular matrix molecules hierarchically organized within the tissues. By dry weight, connective tissues are mostly composed of fibrillar collagens. However, several other forms of collagens play essential roles in the regulation of fibrillar collagen organization and assembly, in the establishment of basement membrane networks that provide support for vasculature for connective tissues, and in the formation of extensive filamentous networks that allow for cell-extracellular matrix interactions as well as maintain connective tissue integrity. The structures and functions of these collagens are discussed in this chapter. Furthermore, collagen synthesis is a multi-step process that includes gene transcription, translation, post-translational modifications within the cell, triple helix formation, extracellular secretion, extracellular modifications, and then fibril assembly, fibril modifications, and fiber formation. Each step of collagen synthesis and fibril assembly is highly dependent upon the biochemical structure of the collagen molecules created and how they are modified in the cases of development and maturation. Likewise, when the biochemical structures of collagens or are compromised or these molecules are deficient in the tissues - in developmental diseases, degenerative conditions, or injuries - then the ultimate form and function of the connective tissues are impaired. In this chapter, we also review how biochemistry plays a role in each of the processes involved in collagen synthesis and assembly, and we describe differences seen by anatomical location and region within tendons. Moreover, we discuss how the structures of the molecules, fibrils, and fibers contribute to connective tissue physiology in health, and in pathology with injury and repair.


Assuntos
Colágeno , Matriz Extracelular , Tecido Conjuntivo , Colágenos Fibrilares , Tendões
5.
Adv Exp Med Biol ; 1348: 105-126, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34807416

RESUMO

Collagens are the most abundant components of the extracellular matrix (ECM) and many types of soft tissues. Elastin is another major component of certain soft tissues, such as arterial walls and ligaments. It is an insoluble polymer of the monomeric soluble precursor tropoelastin, and the main component of elastic fibers in matrix tissue where it provides elastic recoil and resilience to a variety of connective tissues, e.g., aorta and ligaments. Elastic fibers regulate activity of transforming growth factors ß (TGFß) through their association with fibrillin microfibrils. Elastin also plays a role in cell adhesion, cell migration, and has the ability to participate in cell signaling. Mutations in the elastin gene lead to cutis laxa. Many other molecules, though lower in quantity, function as essential, structural and/or functional components of the extracellular matrix in soft tissues. Some of these are reviewed in this chapter. Besides their basic structure, biochemistry and physiology, their roles in disorders of soft tissues are discussed only briefly as most chapters in this volume deal with relevant individual compounds. Fibronectin with its multidomain structure plays a role of "master organizer" in matrix assembly as it forms a bridge between cell surface receptors, e.g., integrins, and compounds such collagen, proteoglycans and other focal adhesion molecules. It also plays an essential role in the assembly of fibrillin-1 into a structured network. Though the primary role of fibrinogen is in clot formation, after conversion to fibrin by thrombin it also binds to a variety of compounds, particularly to various growth factors, and as such, fibrinogen is a player in cardiovascular and extracellular matrix physiology. Laminins contribute to the structure of the ECM and modulate cellular functions such as adhesion, differentiation, migration, stability of phenotype, and resistance towards apoptosis. Fibrillins represent the predominant core of microfibrils in elastic as well as non-elastic extracellular matrixes, and interact closely with tropoelastin and integrins. Not only do microfibrils provide structural integrity of specific organ systems, but they also provide basis for elastogenesis in elastic tissues. Fibrillin is important for the assembly of elastin into elastic fibers. Mutations in the fibrillin-1 gene are closely associated with Marfan syndrome. Latent TGFß binding proteins (LTBPs) are included here as their structure is similar to fibrillins. Several categories of ECM components described after fibrillins are sub-classified as matricellular proteins, i.e., they are secreted into ECM, but do not provide structure. Rather they interact with cell membrane receptors, collagens, proteases, hormones and growth factors, communicating and directing cell-ECM traffic. Fibulins are tightly connected with basement membranes, elastic fibers and other components of extracellular matrix and participate in formation of elastic fibers. Matrilins have been emerging as a new group of supporting actors, and their role in connective tissue physiology and pathophysiology has not been fully characterized. Tenascins are ECM polymorphic glycoproteins found in many connective tissues in the body. Their expression is regulated by mechanical stress both during development and in adulthood. Tenascins mediate both inflammatory and fibrotic processes to enable effective tissue repair and play roles in pathogenesis of Ehlers-Danlos, heart disease, and regeneration and recovery of musculo-tendinous tissue. One of the roles of thrombospondin 1 is activation of TGFß. Increased expression of thrombospondin and TGFß activity was observed in fibrotic skin disorders such as keloids and scleroderma. Cartilage oligomeric matrix protein (COMP) or thrombospondin-5 is primarily present in the cartilage. High levels of COMP are present in fibrotic scars and systemic sclerosis of the skin, and in tendon, especially with physical activity, loading and post-injury. It plays a role in vascular wall remodeling and has been found in atherosclerotic plaques as well.


Assuntos
Elastina , Laminina , Proteínas de Ligação ao Cálcio , Tecido Conjuntivo , Elastina/genética , Matriz Extracelular , Fibrilina-1/genética , Fibrilinas , Fibrinogênio , Fibronectinas , Proteínas Matrilinas , Proteínas dos Microfilamentos , Tenascina , Trombospondinas
6.
Adv Exp Med Biol ; 1348: 161-184, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34807419

RESUMO

Marfan Syndrome (MFS) and Loeys-Dietz Syndrome (LDS) represent heritable connective tissue disorders that segregate with a similar pattern of cardiovascular defects (thoracic aortic aneurysm, mitral valve prolapse/regurgitation, and aortic dilatation with regurgitation). This pattern of cardiovascular defects appears to be expressed along a spectrum of severity in many heritable connective tissue disorders and raises suspicion of a relationship between the normal development of connective tissues and the cardiovascular system. With overwhelming evidence of the involvement of aberrant Transforming Growth Factor-beta (TGF-ß) signaling in MFS and LDS, this signaling pathway may represent the common link in the relationship between connective tissue disorders and their associated cardiovascular complications. To further explore this hypothetical link, this chapter will review the TGF-ß signaling pathway, the heritable connective tissue syndromes related to aberrant TGF-ß signaling, and will discuss the pathogenic contribution of TGF-ß to these syndromes with a primary focus on the cardiovascular system.


Assuntos
Aneurisma da Aorta Torácica , Sistema Cardiovascular , Síndrome de Loeys-Dietz , Síndrome de Marfan , Tecido Conjuntivo , Humanos , Síndrome de Loeys-Dietz/genética , Síndrome de Marfan/complicações , Síndrome de Marfan/genética , Transdução de Sinais , Fator de Crescimento Transformador beta/genética , Fatores de Crescimento Transformadores
7.
Stomatologiia (Mosk) ; 100(5): 7-14, 2021.
Artigo em Russo | MEDLINE | ID: mdl-34752027

RESUMO

OBJECTIVE: The purpose of this investigation was to explore the quality of 38, 48 teeth's hard tissues at different eruption stages and mandibular bone in different postpartum ontogenesis periods. MATERIAL AND METHODS: The research involved 102 male patients divided into groups according to their age: 15-20, 21-30 years old, they were extracted one tooth 38, 48 without inflammatory process signs and a fragment of the mandibular bone alveolar part in the projection of the teeth 38, 48 for orthodontic indications. In the comparison group (49 observations without signs of connective tissue dysplasia), in the study group (53 observations with signs of connective tissue dysplasia) we extracted teeth 38, 48 which were in the bone tissue. We analyzed condition of crown and root systems of extracted 38, 48 teeth, densitometric density of mineral component, size of enamel prisms, size of prismatic shells of organic matrix, spatial organization of collagen fibers in bone tissue, size characteristics of bone plates and mineralization centers of bone tissue. Processing of the obtained data was performed by methods of variation statistics using standard packages Microsoft Excel 2008, Statistica 12.0. RESULTS: The paper reveals one of the surgical dentistry pressing issues related to the tething mechanism of lower human wisdom teeth, considered by the authors from the position of tissue disorders in collagen type 1 observed in connective tissue dysplasia. At age of 15-20 years in connective tissue dysplasia, the enamel prisms hypomineralized areas are generalized; at age of 21-30 years the hypomineralized areas are characterized by local changes. At the age of 15-20 years in connective tissue dysplasia the bone plates splitting is observed at the level of most fibrils, collagen fibers have insufficiently oriented direction in contrast to the age group of 21-30 years where bone plates splitting is characteristic for single fibrils and collagen fibrils are clearly oriented. CONCLUSION: Morphological and histological changes in teeth 38, 48 and in bone tissue prevent correct and timely teething at 15-20 years and create more favorable conditions for teething at 21-30 years with a slower rate in connective tissue dysplasia, but in both groups teeth eruption occurs under unfavorable anatomic conditions.


Assuntos
Doenças do Tecido Conjuntivo , Esmalte Dentário , Adolescente , Adulto , Tecido Conjuntivo , Feminino , Humanos , Masculino , Minerais , Erupção Dentária , Adulto Jovem
8.
Clin Oral Implants Res ; 32 Suppl 21: 157-173, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34642984

RESUMO

OBJECTIVES: To review the available literature on patient-reported outcome measures (PROMs) following soft tissue augmentation at implant sites. MATERIALS AND METHODS: A comprehensive electronic and manual search was performed to identify clinical studies that involved soft tissue augmentation around dental implants and reported PROMs, including post-operative morbidity, painkillers intake, quality of life, aesthetics and satisfactions. RESULTS: Nineteen articles were included in the qualitative analysis. Autogenous grafts (free gingival graft and connective tissue graft), acellular dermal matrix and xenogeneic collagen matrix were utilized, either with a bilaminar- or an apically positioned flap approach. PROMs reported in the literature included perceived hardship of the procedure and pain during the surgery, post-operative morbidity, painkillers intake, number of days with discomfort, satisfaction, aesthetic evaluation, quality of life and willingness to undergo the treatment again. Most of the included studies showed similar PROMs between autogenous grafts and substitutes, in terms of post-operative morbidity, painkillers intake, quality of life, aesthetic assessment and satisfaction. Nevertheless, a trend towards lower post-operative discomfort was observed for graft substitutes. High scores for patient satisfaction and aesthetic evaluation were observed in all the interventions compared to non-grafted sites. CONCLUSIONS: PROMs represent a crucial endpoint of clinical studies evaluating the outcomes of soft tissue grafts at implant sites. Most of the studies did not find significant differences in terms of patient morbidity and painkillers between autogenous grafts and substitutes. Soft tissue grafting can enhance patient satisfaction and aesthetic evaluation compared to non-grafted sites.


Assuntos
Implantes Dentários , Qualidade de Vida , Tecido Conjuntivo , Estética Dentária , Humanos , Medidas de Resultados Relatados pelo Paciente
10.
Acta Odontol Latinoam ; 34(1): 119-126, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34570156

RESUMO

The aim of this pilot study was to evaluate the impact of the association of free gingival graft (FGG) or collagen-matrix xenograft (CMX) to deproteinized bovine bone graft (DBBG) on the preservation of post-extraction sockets with facial-wall defects. Sixteen patients who presented a maxillary tooth with a facial bone defect and indication of extraction were selected. After the surgical procedure, all the post-extraction sockets were filled with DBBG and covered with a collagen membrane. The cervical part of the socket was then sealed with either FGG or CMX. Clinical and tomographic analyses were performed at baseline and 4 months after the grafting procedure. The FGG sockets showed higher values for the width of the bone ridge than the CMX sockets at 4 months. There was no difference regarding biopsy composition. In conclusion, regardless of the type of soft tissue graft used, socket preservation with DBBG at sites presenting facial bone defects enabled implant placement without further guided bone regeneration, whether the sockets were sealed with FGG or CMX.


Assuntos
Perda do Osso Alveolar , Aumento do Rebordo Alveolar , Substitutos Ósseos , Animais , Bovinos , Tecido Conjuntivo , Humanos , Projetos Piloto , Extração Dentária , Alvéolo Dental/cirurgia
11.
Acta Odontol Latinoam ; 34(2): 119-126, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34570859

RESUMO

The aim of this pilot study was to evaluate the impact of the association of free gingival graft (FGG) or collagen-matrix xenograft (CMX) to deproteinized bovine bone graft (DBBG) on the preservation of post-extraction sockets with facial-wall defects. Sixteen patients who presented a maxillary tooth with a facial bone defect and indication of extraction were selected. After the surgical procedure, all the post-extraction sockets were filled with DBBG and covered with a collagen membrane. The cervical part of the socket was then sealed with either FGG or CMX. Clinical and tomographic analyses were performed at baseline and 4 months after the grafting procedure. The FGG sockets showed higher values for the width of the bone ridge than the CMX sockets at 4 months. There was no difference regarding biopsy composition. In conclusion, regardless of the type of soft tissue graft used, socket preservation with DBBG at sites presenting facial bone defects enabled implant placement without further guided bone regeneration, whether the sockets were sealed with FGG or CMX.


Assuntos
Aumento do Rebordo Alveolar , Alvéolo Dental , Animais , Bovinos , Tecido Conjuntivo , Humanos , Projetos Piloto , Extração Dentária , Alvéolo Dental/cirurgia
12.
Compend Contin Educ Dent ; 42(9): 520-526, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34555914

RESUMO

A proper diagnostic and treatment planning process for dental implant rehabilitations should include a checklist of key factors to help clinicians avoid potential complications. Such a checklist should encompass evaluation of the soft- and hard-tissue volume buccal to each implant, as this has been shown to aid in maintaining marginal bone levels long-term. Thus, as part of surgical planning, a decision to augment the soft tissue should be considered. The autogenous palatal graft has long been considered the "gold standard" for soft-tissue augmentation; however, the benefits of this approach should be weighed against the potential complications associated with a secondary surgical site as well as the patient's desire for as pain-free an experience as possible. The volume-stable collagen matrix (VSCM) is a promising material with favorable healing characteristics and volume thickness maintenance of up to 3 years in current literature. This article presents two cases that demonstrate the clinical advantages of a VSCM over the use of autogenous palatal grafts as part of the authors' "10 Keys" principles of augmenting the volume and thickness of peri-implant tissues.


Assuntos
Tecido Conjuntivo , Implantes Dentários , Colágeno , Tecido Conjuntivo/transplante , Implantação Dentária Endo-Óssea , Gengiva/cirurgia , Humanos , Palato
13.
Artigo em Inglês | MEDLINE | ID: mdl-34547076

RESUMO

The gingival thickness (GT) and keratinized tissue width (KTW) constitute the gingival phenotype, a concept that has received a great deal of appreciation in recent years. Gingival phenotype modification has been achieved via different surgical techniques and grafting materials. Despite the superiority of autogenous grafts, their increased patient morbidity and limited recourse has led to the development of graft substitutes. The human dermal matrix is a notable example that, depending on its processing method, can become freeze-dried or solvent-dehydrated acellular dermal matrix (FDADM and SDADM, respectively). This article reports the 9-year outcomes of a randomized clinical trial regarding gingival phenotype modification following root coverage with FDADM and SDADM. Twelve of the original 20 patients were available at the 9-year follow-up. Overall, the outcomes of gingival phenotype modification were maintained in both groups and at all sites after 9 years. For KTW, an incremental increase was observed over time in both groups, and minimal or no changes were noted in GT from the 1-year recall to the 9-year recall. However, the gingival margin level showed an apical shift for both groups.


Assuntos
Retração Gengival , Tecido Conjuntivo , Gengiva , Retração Gengival/cirurgia , Humanos , Fenótipo , Raiz Dentária , Resultado do Tratamento
14.
Analyst ; 146(19): 5848-5854, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34498612

RESUMO

It is shown that a pixel-level image fusion technique can produce images that combine the spatial resolution of optical microscopy images of haematoxylin and eosin (H&E) stained tissue with the chemical information in Fourier transform infrared (FTIR) images. The fused images show minimal distortion and the higher spatial resolution of the H&E images overcomes the diffraction limit on the spatial resolution of the FTIR images. A consideration of the FTIR spectra of nucleic acids and collagen can explain the changes in contrast between non-cancerous oral epithelium and underlying stroma within fused images formed by combining an H&E stain of oral tissue with FTIR images of the tissue obtained at a number of wavenumbers.


Assuntos
Tecido Conjuntivo , Microscopia , Colágeno , Análise de Fourier , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Sci Rep ; 11(1): 17926, 2021 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-34504132

RESUMO

The extracellular matrix architecture is composed of supramolecular fibrillar networks that define tissue specific cellular microenvironments. Hemicentins (Hmcn1 and Hmcn2) are ancient and very large members (> 600 kDa) of the fibulin family, whose short members are known to guide proper morphology and functional behavior of specialized cell types predominantly in elastic tissues. However, the tissue distribution and function of Hemicentins within the cellular microenvironment of connective tissues has remained largely unknown. Performing in situ hybridization and immunofluorescence analyses, we found that mouse Hmcn1 and Hmcn2 show a complementary distribution throughout different tissues and developmental stages. In postnatal dermal-epidermal junctions (DEJ) and myotendinous junctions (MTJ), Hmcn1 is primarily produced by mesenchymal cells (fibroblasts, tenocytes), Hmcn2 by cells of epithelial origin (keratinocytes, myocytes). Hmcn1-/- mice are viable and show no overt phenotypes in tissue tensile strength and locomotion tests. However, transmission electron microscopy revealed ultrastructural basement membrane (BM) alterations at the DEJ and MTJ of Hmcn1-/- mice, pointing to a thus far unknown role of Hmcn1 for BM and connective tissue boundary integrity.


Assuntos
Derme/metabolismo , Epiderme/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Matriz Extracelular/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Transdução de Sinais/genética , Tendões/metabolismo , Animais , Células Cultivadas , Tecido Conjuntivo/metabolismo , Desenvolvimento Embrionário/genética , Proteínas da Matriz Extracelular/genética , Feminino , Fibroblastos/metabolismo , Queratinócitos/metabolismo , Locomoção/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Resistência à Tração
16.
Int J Mol Sci ; 22(18)2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34576312

RESUMO

Ehlers-Danlos syndromes (EDS) are an inherited heterogeneous group of connective tissue disorders characterized by an abnormal collagen synthesis affecting skin, ligaments, joints, blood vessels, and other organs. It is one of the oldest known causes of bruising and bleeding, and it was described first by Hippocrates in 400 BC. In the last years, multiple gene variants involved in the pathogenesis of specific EDS subtypes have been identified; moreover, new clinical diagnostic criteria have been established. New classification models have also been studied in order to differentiate overlapping conditions. Moreover, EDS shares many characteristics with other similar disorders. Although distinguishing between these seemingly identical conditions is difficult, it is essential in ensuring proper patient care. Currently, there are many genetic and molecular studies underway to clarify the etiology of some variants of EDS. However, the genetic basis of the hypermobile type of EDS (hEDS) is still unknown. In this review, we focused on the study of two of the most common forms of EDS-classic and hypermobile-by trying to identify possible biomarkers that could be of great help to confirm patients' diagnosis and their follow up.


Assuntos
Síndrome de Ehlers-Danlos/diagnóstico , Biomarcadores/sangue , Biomarcadores/metabolismo , Biomarcadores/urina , Tecido Conjuntivo/metabolismo , Tecido Conjuntivo/patologia , Síndrome de Ehlers-Danlos/genética , Síndrome de Ehlers-Danlos/metabolismo , Predisposição Genética para Doença , Humanos
17.
Nat Commun ; 12(1): 5544, 2021 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-34545087

RESUMO

Mass spectrometry imaging (MSI) is an emerging technology that holds potential for improving, biomarker discovery, metabolomics research, pharmaceutical applications and clinical diagnosis. Despite many solutions being developed, the large data size and high dimensional nature of MSI, especially 3D datasets, still pose computational and memory complexities that hinder accurate identification of biologically relevant molecular patterns. Moreover, the subjectivity in the selection of parameters for conventional pre-processing approaches can lead to bias. Therefore, we assess if a probabilistic generative model based on a fully connected variational autoencoder can be used for unsupervised analysis and peak learning of MSI data to uncover hidden structures. The resulting msiPL method learns and visualizes the underlying non-linear spectral manifold, revealing biologically relevant clusters of tissue anatomy in a mouse kidney and tumor heterogeneity in human prostatectomy tissue, colorectal carcinoma, and glioblastoma mouse model, with identification of underlying m/z peaks. The method is applied for the analysis of MSI datasets ranging from 3.3 to 78.9 GB, without prior pre-processing and peak picking, and acquired using different mass spectrometers at different centers.


Assuntos
Imageamento Tridimensional , Redes Neurais de Computação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Algoritmos , Animais , Tecido Conjuntivo/diagnóstico por imagem , Tecido Conjuntivo/patologia , Aprendizado Profundo , Modelos Animais de Doenças , Humanos , Rim/diagnóstico por imagem , Metabolômica , Camundongos , Neoplasias/diagnóstico por imagem , Neoplasias/metabolismo , Dinâmica não Linear , Reprodutibilidade dos Testes , alfa-Defensinas/metabolismo
18.
J Vis Exp ; (174)2021 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-34487119

RESUMO

Fibroblasts are phenotypically highly dynamic cells, which quickly transdifferentiate into myofibroblasts in response to biochemical and biomechanical stimuli. The current understanding of fibrotic processes, including cardiac fibrosis, remains poor, which hampers the development of new anti-fibrotic therapies. Controllable and reliable human model systems are crucial for a better understanding of fibrosis pathology. This is a highly reproducible and scalable protocol to generate engineered connective tissues (ECT) in a 48-well casting plate to facilitate studies of fibroblasts and the pathophysiology of fibrotic tissue in a 3-dimensional (3D) environment. ECT are generated around the poles with tunable stiffness, allowing for studies under a defined biomechanical load. Under the defined loading conditions, phenotypic adaptations controlled by cell-matrix interactions can be studied. Parallel testing is feasible in the 48-well format with the opportunity for the time-course analysis of multiple parameters, such as tissue compaction and contraction against the load. From these parameters, biomechanical properties such as tissue stiffness and elasticity can be studied.


Assuntos
Fibroblastos , Miofibroblastos , Tecido Conjuntivo , Elasticidade , Fibroblastos/patologia , Fibrose , Humanos
19.
Int J Mol Sci ; 22(17)2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34502387

RESUMO

Strenuous and unaccustomed exercise frequently lead to what has been coined "delayed onset muscle soreness" (DOMS). As implied by this term, it has been proposed that the associated pain and stiffness stem from micro-lesions, inflammation, or metabolite accumulation within the skeletal muscle. However, recent research points towards a strong involvement of the connective tissue. First, according to anatomical studies, the deep fascia displays an intimate structural relationship with the underlying skeletal muscle and may therefore be damaged during excessive loading. Second, histological and experimental studies suggest a rich supply of algogenic nociceptors whose stimulation evokes stronger pain responses than muscle irritation. Taken together, the findings support the hypothesis that DOMS originates in the muscle-associated connective tissue rather than in the muscle itself. Sports and fitness professionals designing exercise programs should hence consider fascia-oriented methods and techniques (e.g., foam rolling, collagen supplementation) when aiming to treat or prevent DOMS.


Assuntos
Tecido Conjuntivo/fisiologia , Fáscia/fisiologia , Mialgia/fisiopatologia , Exercício Físico/fisiologia , Humanos , Contração Muscular/fisiologia , Músculo Esquelético/fisiopatologia , Músculos/fisiopatologia , Mialgia/metabolismo , Dor/metabolismo , Dor/fisiopatologia , Fatores de Tempo
20.
Int J Implant Dent ; 7(1): 86, 2021 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-34435229

RESUMO

BACKGROUND: Nowadays, due to the esthetic and social demands of patients, conventional staged protocols seem to be increasingly replaced by faster, one-step protocols. The purpose of the present systematic review is to assess the peri-implant soft tissue changes after immediate implant placement and provisionalization (IIPP) comparing patients treated with or without a sub-epithelial connective tissue graft (SCTG) when replacing a single tooth in the esthetic region. METHODS: The present systematic review was written following the PRISMA checklist. Immediate implants placed with a connective tissue graft and without one were compared. The researched primary outcomes were the mid-buccal mucosa level (MBML) facial soft tissue thickness (FSTT) and marginal bone loss (MBL). The weighted mean differences (WMD) were estimated for all three outcomes. RESULTS: The change in the mid-buccal mucosa level in the intervention group was significantly higher (WMD 0.54; 95% CI 0.33-0.75), with no indication of heterogeneity (I2 = 16%). The facial soft tissue thickness increased significantly in the intervention group (WMD 0.79; 95% CI 0.37-1.22). The marginal bone loss was significantly higher in the control group (WMD 0.13; 95% CI 0.07-0.18), with no indication of heterogeneity (I2 = 0%). CONCLUSIONS: The results of the meta-analyses showed a statistically significant reduced change of the marginal bone loss and vestibular recession, as well as higher soft tissue thickness, when a graft was used. The included studies had a short observation time; therefore, studies with longer follow-ups are needed to confirm these findings.


Assuntos
Estética Dentária , Carga Imediata em Implante Dentário , Tecido Conjuntivo/diagnóstico por imagem , Humanos , Mucosa Bucal/cirurgia , Radiografia
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