Tissue-engineering strategies for the tendon/ligament-to-bone insertion.

PubMed

Smith, Lester; Xia, Younan; Galatz, Leesa M; Genin, Guy M; Thomopoulos, Stavros

2012-01-01

Injuries to connective tissues are painful and disabling and result in costly medical expenses. These injuries often require reattachment of an unmineralized connective tissue to bone. The uninjured tendon/ligament-to-bone insertion (enthesis) is a functionally graded material that exhibits a gradual transition from soft tissue (i.e., tendon or ligament) to hard tissue (i.e., mineralized bone) through a fibrocartilaginous transition region. This transition is believed to facilitate force transmission between the two dissimilar tissues by ameliorating potentially damaging interfacial stress concentrations. The transition region is impaired or lost upon tendon/ligament injury and is not regenerated following surgical repair or natural healing, exposing the tissue to risk of reinjury. The need to regenerate a robust tendon-to-bone insertion has led a number of tissue engineering repair strategies. This review treats the tendon-to-bone insertion site as a tissue structure whose primary role is mechanical and discusses current and emerging strategies for engineering the tendon/ligament-to-bone insertion in this context. The focus lies on strategies for producing mechanical structures that can guide and subsequently sustain a graded tissue structure and the associated cell populations.

Specialized connective tissue: bone, the structural framework of the upper extremity

PubMed Central

Weatherholt, Alyssa M.; Fuchs, Robyn K.; Warden, Stuart J.

2011-01-01

Bone is a connective tissue containing cells, fibers and ground substance. There are many functions in the body in which the bone participates, such as storing minerals, providing internal support, protecting vital organs, enabling movement, and providing attachment sites for muscles and tendons. Bone is unique because its collagen framework absorbs energy, while the mineral encased within the matrix allows bone to resist deformation. This article provides an overview of the structure and function of bone tissue from a macroscopic to microscopic level and discusses the physiological processes contributing to upper extremity bone health. It concludes by discussing common conditions influencing upper extremity bone health. PMID:22047807

Anatomy and histology of the newly discovered adipose sac structure within the labia majora: international original research.

PubMed

Ostrzenski, Adam; Krajewski, Pawel; Davis, Kern

2016-09-01

To determine whether there is any new anatomical structure present within the labia majora. A case serial study was executed on eleven consecutive fresh human female cadavers. Stratum-by-stratum dissections of the labia majora were performed. Twenty-two anatomic dissections of labia majora were completed. Eosin and Hematoxylin agents were used to stain newly discovered adipose sac's tissues of the labia majora and the cylinder-like structures, which cover condensed adipose tissues. The histology of these two structures was compared. All dissected labia majora demonstrated the presence of the anatomic existence of the adipose sac structure. Just under the dermis of the labia majora, the adipose sac was located, which was filled with lobules containing condensed fatty tissues in the form of cylinders. The histological investigation established that the well-organized fibro-connective-adipose tissues represented the adipose sac. The absence of descriptions of the adipose sac within the labia majora in traditional anatomic and gynecologic textbooks was noted. In this study group, the newly discovered adipose sac is consistently present within the anatomical structure of the labia majora. The well-organized fibro-connective-adipose tissue represents microscopic characteristic features of the adipose sac.

Ultrastructure of periprosthetic Dacron knee ligament tissue. Two cases of ruptured anterior cruciate ligament reconstruction.

PubMed

Salvi, M; Velluti, C; Misasi, M; Bartolozzi, P; Quacci, D; Dell'Orbo, C

1991-04-01

Light- and electron-microscopic investigations were performed on two failed Dacron ligaments that had been removed from 2 patients shortly after failure of the implant 2-3 years after reconstruction of the anterior cruciate ligament. Two different cell populations and matrices were correlated with closeness to the Dacron threads. Fibroblasts surrounded by connective tissue with collagen fibrils were located far from the Dacron threads. Roundish cells, appearing to be myofibroblasts surrounded by a more lax connective tissue and elastic fibers, were found close to the Dacron threads. The presence of myofibroblasts and the matrix differentiation could be attributed to the different mechanical forces acting on the Dacron and on the connective tissue because of their different coefficients of elasticity. The sparse occurrence of inflammatory cells in the synovial membrane and in the connective tissue surrounding the Dacron supports the biologic inertness of this artificial material. However, the repair tissue was not structured to resist tension stresses.

[Evaluation of Cepan Cream after 15 years of treatment of burn scars].

PubMed

Stozkowska, Wiesława

2002-01-01

Cepan Cream is used for the topical treatment of scars and keloids resulting from burns, post-operative scars, and contractures. Cepan Cream makes scars more elastic, softer and paler. Plant extracts, heparin and allantoin in Cepan act on the biochemical processes in the developing connective tissue, preventing the formation of hyperplastic scars. These active ingredients enhance swelling, softening and loosening of connective tissue. It exerts softening and smoothing action on indurated and hyperplastic scar tissue, improving collagen structure. It promotes tissue regeneration and reduces exuberant granulation. Cepan is well tolerated.

Characterization of somatic embryo attached structures in Feijoa sellowiana Berg. (Myrtaceae).

PubMed

Correia, Sandra M; Canhoto, Jorge M

2010-06-01

The presence of an attached organ to somatic embryos of angiosperms connecting the embryo to the supporting tissue has been a subject of controversy. This study shows that 67% of the morphologically normal somatic embryos of Feijoa sellowiana possess this type of organ and that its formation was not affected by culture media composition. Histological and ultrastructural analysis indicated that the attached structures of somatic embryos displayed a great morphological diversity ranging from a few cells to massive and columnar structures. This contrast with the simple suspensors observed in zygotic embryos which were only formed by five cells. As well as the suspensor of zygotic embryos, somatic embryo attached structures undergo a process of degeneration in later stages of embryo development. Other characteristic shared by zygotic suspensors and somatic embryo attached structures was the presence of thick cell walls surrounding the cells. Elongated thin filaments were often associated with the structures attached to somatic embryos, whereas in other cases, tubular cells containing starch grains connected the embryo to the supporting tissue. These characteristics associated with the presence of plasmodesmata in the cells of the attached structures seem to indicate a role on embryo nutrition. However, cell proliferation in the attached structures resulting into new somatic embryos may also suggest a more complex relationship between the embryo and the structures connecting it to the supporting tissue.

Designing the stem cell microenvironment for guided connective tissue regeneration.

PubMed

Bogdanowicz, Danielle R; Lu, Helen H

2017-12-01

Adult mesenchymal stem cells (MSCs) are an attractive cell source for regenerative medicine because of their ability to self-renew and their capacity for multilineage differentiation and tissue regeneration. For connective tissues, such as ligaments or tendons, MSCs are vital to the modulation of the inflammatory response following acute injury while also interacting with resident fibroblasts to promote cell proliferation and matrix synthesis. To date, MSC injection for connective tissue repair has yielded mixed results in vivo, likely due to a lack of appropriate environmental cues to effectively control MSC response and promote tissue healing instead of scar formation. In healthy tissues, stem cells reside within a complex microenvironment comprising cellular, structural, and signaling cues that collectively maintain stemness and modulate tissue homeostasis. Changes to the microenvironment following injury regulate stem cell differentiation, trophic signaling, and tissue healing. Here, we focus on models of the stem cell microenvironment that are used to elucidate the mechanisms of stem cell regulation and inspire functional approaches to tissue regeneration. Recent studies in this frontier area are highlighted, focusing on how microenvironmental cues modulate MSC response following connective tissue injury and, more importantly, how this unique cell environment can be programmed for stem cell-guided tissue regeneration. © 2017 New York Academy of Sciences.

Connective tissue fibroblasts and Tcf4 regulate myogenesis

PubMed Central

Mathew, Sam J.; Hansen, Jody M.; Merrell, Allyson J.; Murphy, Malea M.; Lawson, Jennifer A.; Hutcheson, David A.; Hansen, Mark S.; Angus-Hill, Melinda; Kardon, Gabrielle

2011-01-01

Muscle and its connective tissue are intimately linked in the embryo and in the adult, suggesting that interactions between these tissues are crucial for their development. However, the study of muscle connective tissue has been hindered by the lack of molecular markers and genetic reagents to label connective tissue fibroblasts. Here, we show that the transcription factor Tcf4 (transcription factor 7-like 2; Tcf7l2) is strongly expressed in connective tissue fibroblasts and that Tcf4GFPCre mice allow genetic manipulation of these fibroblasts. Using this new reagent, we find that connective tissue fibroblasts critically regulate two aspects of myogenesis: muscle fiber type development and maturation. Fibroblasts promote (via Tcf4-dependent signals) slow myogenesis by stimulating the expression of slow myosin heavy chain. Also, fibroblasts promote the switch from fetal to adult muscle by repressing (via Tcf4-dependent signals) the expression of developmental embryonic myosin and promoting (via a Tcf4-independent mechanism) the formation of large multinucleate myofibers. In addition, our analysis of Tcf4 function unexpectedly reveals a novel mechanism of intrinsic regulation of muscle fiber type development. Unlike other intrinsic regulators of fiber type, low levels of Tcf4 in myogenic cells promote both slow and fast myogenesis, thereby promoting overall maturation of muscle fiber type. Thus, we have identified novel extrinsic and intrinsic mechanisms regulating myogenesis. Most significantly, our data demonstrate for the first time that connective tissue is important not only for adult muscle structure and function, but is a vital component of the niche within which muscle progenitors reside and is a critical regulator of myogenesis. PMID:21177349

Effect of MELT method on thoracolumbar connective tissue: The full study.

PubMed

Sanjana, Faria; Chaudhry, Hans; Findley, Thomas

2017-01-01

Altered connective tissue structure has been identified in adults with chronic low back pain (LBP). A self-care treatment for managing LBP is the MELT method. The MELT method is a hands-off, self-treatment that is said to alleviate chronic pain, release tension and restore mobility, utilizing specialized soft treatments balls, soft body roller and techniques mimicking manual therapy. The objective of this study was to determine whether thickness of thoracolumbar connective tissue and biomechanical and viscoelastic properties of myofascial tissue in the low back region change in subjects with chronic LBP as a result of MELT. This study was designed using a quasi experimental pre-post- design that analyzed data from subjects who performed MELT. Using ultrasound imaging and an algorithm developed in MATLAB, thickness of thoracolumbar connective tissue was analyzed in 22 subjects. A hand-held digital palpation device, called the MyotonPRO, was used to assess biomechanical properties such as stiffness, elasticity, tone and mechanical stress relaxation time of the thoracolumbar myofascial tissue. A forward bending test assessing flexibility and pain scale was added to see if MELT affected subjects with chronic LBP. A significant decrease in connective tissue thickness and pain was observed in participants. Significant increase in flexibility was also recorded. Copyright © 2016 Elsevier Ltd. All rights reserved.

Meat Science and Muscle Biology Symposium: manipulating meat tenderness by increasing the turnover of intramuscular connective tissue.

PubMed

Purslow, P P; Archile-Contreras, A C; Cha, M C

2012-03-01

Controlled reduction of the connective tissue contribution to cooked meat toughness is an objective that would have considerable financial impact in terms of added product value. The amount of intramuscular connective tissue in a muscle appears connected to its in vivo function, so reduction of the overall connective tissue content is not thought to be a viable target. However, manipulation of the state of maturity of the collagenous component is a biologically viable target; by increasing connective tissue turnover, less mature structures can be produced that are functional in vivo but more easily broken down on cooking at temperatures above 60°C, thus improving cooked meat tenderness. Recent work using cell culture models of fibroblasts derived from muscle and myoblasts has identified a range of factors that alter the activity of the principal enzymes responsible for connective tissue turnover, the matrix metalloproteinases (MMP). Fibroblasts cultured from 3 different skeletal muscles from the same animal show different cell proliferation and MMP activity, which may relate to the different connective tissue content and architecture in functionally different muscles. Expression of MMP by fibroblasts is increased by vitamins that can counter the negative effects of oxidative stress on new collagen synthesis. Preliminary work using in situ zymography of myotubes in culture also indicates increased MMP activity in the presence of epinephrine and reactive oxidative species. Comparison of the relative changes in MMP expression from muscle cells vs. fibroblasts shows that myoblasts are more responsive to a range of stimuli. Muscle cells are likely to produce more of the total MMP in muscle tissue as a whole, and the expression of latent forms of the enzymes (i.e., pro-MMP) may vary between oxidative and glycolytic muscle fibers within the same muscle. The implication is that the different muscle fiber composition of different muscles eaten as meat may influence the potential for manipulation of their connective tissue turnover.

Thalamotemporal impairment in temporal lobe epilepsy: a combined MRI analysis of structure, integrity, and connectivity.

PubMed

Keller, Simon S; O'Muircheartaigh, Jonathan; Traynor, Catherine; Towgood, Karren; Barker, Gareth J; Richardson, Mark P

2014-02-01

Thalamic abnormality in temporal lobe epilepsy (TLE) is well known from imaging studies, but evidence is lacking regarding connectivity profiles of the thalamus and their involvement in the disease process. We used a novel multisequence magnetic resonance imaging (MRI) protocol to elucidate the relationship between mesial temporal and thalamic pathology in TLE. For 23 patients with TLE and 23 healthy controls, we performed T1 -weighted (for analysis of tissue structure), diffusion tensor imaging (tissue connectivity), and T1 and T2 relaxation (tissue integrity) MRI across the whole brain. We used connectivity-based segmentation to determine connectivity patterns of thalamus to ipsilateral cortical regions (occipital, parietal, prefrontal, postcentral, precentral, and temporal). We subsequently determined volumes, mean tractography streamlines, and mean T1 and T2 relaxometry values for each thalamic segment preferentially connecting to a given cortical region, and of the hippocampus and entorhinal cortex. As expected, patients had significant volume reduction and increased T2 relaxation time in ipsilateral hippocampus and entorhinal cortex. There was bilateral volume loss, mean streamline reduction, and T2 increase of the thalamic segment preferentially connected to temporal lobe, corresponding to anterior, dorsomedial, and pulvinar thalamic regions, with no evidence of significant change in any other thalamic segments. Left and right thalamotemporal segment volume and T2 were significantly correlated with volume and T2 of ipsilateral (epileptogenic), but not contralateral (nonepileptogenic), mesial temporal structures. These convergent and robust data indicate that thalamic abnormality in TLE is restricted to the area of the thalamus that is preferentially connected to the epileptogenic temporal lobe. The degree of thalamic pathology is related to the extent of mesial temporal lobe damage in TLE. © 2014 The Authors. Epilepsia published by Wiley Periodicals, Inc. on behalf of International League Against Epilepsy.

Microscopic and ultrastructural evidences in human skin following calcium hydroxylapatite filler treatment.

PubMed

Zerbinati, Nicola; D'Este, Edoardo; Parodi, Pier Camillo; Calligaro, Alberto

2017-07-01

This study uses light and electron microscopes to gain a better knowledge of the interactions of calcium hydroxylapatite filler with the connective tissue of the skin and the modifications of the human deep dermis, after 2 months of treatment. Some morphological evidences of this observational study of filler treated tissue support-specific mechanism involved in the structural modifications of both filler microspherules and cells of the connective tissue. They demonstrate the absence of any immunological reaction and show that the used filler is modified very slowly over time by the action of cells of the connective tissue closely related to the filler without any activity of phagocytosis. Furthermore, associated with the modifications of the filler, evidences of stimulatory effects on dermal fibroblasts are reported.

[Imaging of alloplastic ligament implant. An in vivo and in vitro study exemplified by Kevlar].

PubMed

Wening, J V; Katzer, A; Nicolas, V; Hahn, M; Jungbluth, K H; Kratzer A [corrected to Katzer, A

1994-04-01

Neither native X-ray nor CT or NMR allow to evaluate intraarticular implantation results of Kevlar -49 directly. In animal trials, the course of an artificial ligament may only be presumed from connective tissue ingrowth. Although soft tissue structure appears much better in NMR than in CT, direct proof of ligament continuity is still impossible. As soon as the connective tissue becomes continuous, it appears clearly and allows indirect evaluation of the prosthesis, as integrity can be judged by its shape like in natural cruciate ligament. Anatomic preparations show that connective tissue fills up the small space between the two cords of a Kevlar -49 two bundle prosthesis eight weeks after implantation, so that imaging systems show only one intraarticular bundle.

An anatomical and histological study of the structures surrounding the proximal attachment of the hamstring muscles.

PubMed

Pérez-Bellmunt, Albert; Miguel-Pérez, Maribel; Brugué, Marc Blasi; Cabús, Juan Blasi; Casals, Martí; Martinoli, Carlo; Kuisma, Raija

2015-06-01

The proximal attachment of hamstring muscles has a very high incidence of injuries due to a wide number of factors and its morphology may be one of the underlying factors as scientific literature points out. The connective tissue component of the attachment of hamstring muscles is not well known. For this reason the aim of this study is to describe the anatomy and histology surrounding the proximal attachment of the hamstring muscles (PAHM) and its direct anatomic relations. Forty-eight cryopreserved lower limbs have sequentially been studied by means of dissection, anatomical sections and histology. All specimens studied presented an annular connective tissue structure that resembles a retinaculum, which covers and adapts to the attachment of hamstring muscles on the ischial tuberosity. The results show how this retinaculum is continuous with the long head of biceps femoris muscle, however there is a layer of loose connective tissue between the retinaculum and the semitendinosus muscle. Furthermore, this structure receives expansions of the anterior epimysium of the gluteus maximus muscle (GIM). Copyright © 2014 Elsevier Ltd. All rights reserved.

The peri-esophageal connective tissue layers and related compartments: visualization by histology and magnetic resonance imaging.

PubMed

Weijs, T J; Goense, L; van Rossum, P S N; Meijer, G J; van Lier, A L H M W; Wessels, F J; Braat, M N G; Lips, I M; Ruurda, J P; Cuesta, M A; van Hillegersberg, R; Bleys, R L A W

2017-02-01

An organized layer of connective tissue coursing from aorta to esophagus was recently discovered in the mediastinum. The relations with other peri-esophageal fascias have not been described and it is unclear whether this layer can be visualized by non-invasive imaging. This study aimed to provide a comprehensive description of the peri-esophageal fascias and determine whether the connective tissue layer between aorta and esophagus can be visualized by magnetic resonance imaging (MRI). First, T2-weighted MRI scanning of the thoracic region of a human cadaver was performed, followed by histological examination of transverse sections of the peri-esophageal tissue between the thyroid gland and the diaphragm. Secondly, pretreatment motion-triggered MRI scans were prospectively obtained from 34 patients with esophageal cancer and independently assessed by two radiologists for the presence and location of the connective tissue layer coursing from aorta to esophagus. A layer of connective tissue coursing from the anterior aspect of the descending aorta to the left lateral aspect of the esophagus, with a thin extension coursing to the right pleural reflection, was visualized ex vivo in the cadaver on MR images, macroscopic tissue sections, and after histologic staining, as well as on in vivo MR images. The layer connecting esophagus and aorta was named 'aorto-esophageal ligament' and the layer connecting aorta to the right pleural reflection 'aorto-pleural ligament'. These connective tissue layers divides the posterior mediastinum in an anterior compartment containing the esophagus, (carinal) lymph nodes and vagus nerve, and a posterior compartment, containing the azygos vein, thoracic duct and occasionally lymph nodes. The anterior compartment was named 'peri-esophageal compartment' and the posterior compartment 'para-aortic compartment'. The connective tissue layers superior to the aortic arch and at the diaphragm corresponded with the currently available anatomic descriptions. This study confirms the existence of the previously described connective tissue layer coursing from aorta to esophagus, challenging the long-standing paradigm that no such structure exists. A comprehensive, detailed description of the peri-esophageal fascias is provided and, furthermore, it is shown that the connective tissue layer coursing from aorta to esophagus can be visualized in vivo by MRI. © 2016 Anatomical Society.

Understanding the effect of pulsed electric fields on thermostability of connective tissue isolated from beef pectoralis muscle using a model system.

PubMed

Alahakoon, A U; Oey, I; Silcock, P; Bremer, P

2017-10-01

Brisket is a low value/tough meat cut that contains a large amount of connective tissue. Conversion of collagen into gelatin during heating reduces the toughness of the connective tissue however this conversion is slow at low cooking temperatures (around 60°C). The objective of this project was to determine the ability of pulsed electric field (PEF) processing to reduce the thermal stability of connective tissue. To achieve this, a novel model system was designed in which connective tissue obtained from beef deep pectotalis muscle (brisket) was exposed to PEF at combinations of electric field strength (1.0 and 1.5kV/cm) and specific energy (50 and 100kJ/kg) within an agar matrix at electrical conductivities representing the electrical conductivity found in brisket. Differential scanning calorimetry showed that PEF treatment significantly (p<0.05) decreased the denaturation temperature of connective tissue compared to untreated samples. Increasing electric field strength and the specific energy increased the Ringer soluble collagen fraction. PEF treated samples showed higher solubilization compared to the untreated samples at both 60°C and 70°C in heat solubility test. SEM examination of PEF treated (at 1.5kV/cm and 100kJ/kg) and untreated samples revealed that PEF appeared to increase the porosity of the connective tissue structure. These finding suggest that PEF processing is a technology that could be used to improve the tenderness and decrease the cooking time of collagen rich, meat cuts. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of protein-coated nanofibers on conformation of gingival fibroblast spheroids: potential utility for connective tissue regeneration.

PubMed

Kaufman, Gili; Whitescarver, Ryan A; Nunes, Laiz; Palmer, Xavier-Lewis; Skrtic, Drago; Tutak, Wojtek

2018-01-24

Deep wounds in the gingiva caused by trauma or surgery require a rapid and robust healing of connective tissues. We propose utilizing gas-brushed nanofibers coated with collagen and fibrin for that purpose. Our hypotheses are that protein-coated nanofibers will: (i) attract and mobilize cells in various spatial orientations, and (ii) regulate the expression levels of specific extracellular matrix (ECM)-associated proteins, determining the initial conformational nature of dense and soft connective tissues. Gingival fibroblast monolayers and 3D spheroids were cultured on ECM substrate and covered with gas-blown poly-(DL-lactide-co-glycolide) (PLGA) nanofibers (uncoated/coated with collagen and fibrin). Cell attraction and rearrangement was followed by F-actin staining and confocal microscopy. Thicknesses of the cell layers, developed within the nanofibers, were quantified by ImageJ software. The expression of collagen1α1 chain (Col1α1), fibronectin, and metalloproteinase 2 (MMP2) encoding genes was determined by quantitative reverse transcription analysis. Collagen- and fibrin- coated nanofibers induced cell migration toward fibers and supported cellular growth within the scaffolds. Both proteins affected the spatial rearrangement of fibroblasts by favoring packed cell clusters or intermittent cell spreading. These cell arrangements resembled the structural characteristic of dense and soft connective tissues, respectively. Within three days of incubation, fibroblast spheroids interacted with the fibers, and grew robustly by increasing their thickness compared to monolayers. While the ECM key components, such as fibronectin and MMP2 encoding genes, were expressed in both protein groups, Col1α1 was predominantly expressed in bundled fibroblasts grown on collagen fibers. This enhanced expression of collagen1 is typical for dense connective tissue. Based on results of this study, our gas-blown, collagen- and fibrin-coated PLGA nanofibers are viable candidates for engineering soft and dense connective tissues with the required structural characteristics and functions needed for wound healing applications. Rapid regeneration of these layers should enhance healing of open wounds in a harsh oral environment.

Mechanisms of lamellar collagen formation in connective tissues.

PubMed

Ghazanfari, Samaneh; Khademhosseini, Ali; Smit, Theodoor H

2016-08-01

The objective of tissue engineering is to regenerate functional tissues. Engineering functional tissues requires an understanding of the mechanisms that guide the formation and evolution of structure in the extracellular matrix (ECM). In particular, the three-dimensional (3D) collagen fiber arrangement is important as it is the key structural determinant that provides mechanical integrity and biological function. In this review, we survey the current knowledge on collagen organization mechanisms that can be applied to create well-structured functional lamellar tissues and in particular intervertebral disc and cornea. Thus far, the mechanisms behind the formation of cross-aligned collagen fibers in the lamellar structures is not fully understood. We start with cell-induced collagen alignment and strain-stabilization behavior mechanisms which can explain a single anisotropically aligned collagen fiber layer. These mechanisms may explain why there is anisotropy in a single layer in the first place. However, they cannot explain why a consecutive collagen layer is laid down with an alternating alignment. Therefore, we explored another mechanism, called liquid crystal phasing. While dense concentrations of collagen show such behavior, there is little evidence that the conditions for liquid crystal phasing are actually met in vivo. Instead, lysyl aldehyde-derived collagen cross-links have been found essential for correct lamellar matrix deposition. Furthermore, we suggest that supra-cellular (tissue-level) shear stress may be instrumental in the alignment of collagen fibers. Understanding the potential mechanisms behind the lamellar collagen structure in connective tissues will lead to further improvement of the regeneration strategies of functional complex lamellar tissues. Copyright © 2016 Elsevier Ltd. All rights reserved.

Morphology and ultrastructure of the esophagus during the ontogeny of the spider crab Maja brachydactyla (Decapoda, Brachyura, Majidae).

PubMed

Castejón, Diego; Rotllant, Guiomar; Ribes, Enric; Durfort, Mercè; Guerao, Guillermo

2018-06-01

The esophagus of the eucrustaceans is known as a short tube that connects the mouth with the stomach but has generally received little attention by the carcinologists, especially during the larval stages. By this reason, the present study is focused on the morphology and ultrastructure of the esophagus in the brachyuran Maja brachydactyla during the larval development and adult stage. The esophagus shows internally four longitudinal folds. The simple columnar epithelium is covered by a thick cuticle. The epithelial cells of the adults are intensively interdigitated and show abundant apical mitochondria and bundles of filamentous structures. The cuticle surface has microspines and mutually exclusive pores. Three muscle layers surrounded by the connective tissue are reported: circular muscles forming a broad continuous band, longitudinal muscle bundles adjacent to the circular muscles, and dilator muscles crossing the connective tissue vertically toward the epithelium. The connective tissue has rosette glands. The esophagus of the larvae have epithelial cells with big vesicles but poorly developed interdigitations and filamentous structures, the cuticle is formed by a procuticle without differentiated exocuticle and endocuticle, the connective layer is thin and the rosette glands are absent. The observed features can be explained by his role in the swallowing of the food. © 2018 Wiley Periodicals, Inc.

Next Generation Tissue Engineering of Orthopedic Soft Tissue-to-Bone Interfaces.

PubMed

Boys, Alexander J; McCorry, Mary Clare; Rodeo, Scott; Bonassar, Lawrence J; Estroff, Lara A

2017-09-01

Soft tissue-to-bone interfaces are complex structures that consist of gradients of extracellular matrix materials, cell phenotypes, and biochemical signals. These interfaces, called entheses for ligaments, tendons, and the meniscus, are crucial to joint function, transferring mechanical loads and stabilizing orthopedic joints. When injuries occur to connected soft tissue, the enthesis must be re-established to restore function, but due to structural complexity, repair has proven challenging. Tissue engineering offers a promising solution for regenerating these tissues. This prospective review discusses methodologies for tissue engineering the enthesis, outlined in three key design inputs: materials processing methods, cellular contributions, and biochemical factors.

Next Generation Tissue Engineering of Orthopedic Soft Tissue-to-Bone Interfaces

PubMed Central

Boys, Alexander J.; McCorry, Mary Clare; Rodeo, Scott; Bonassar, Lawrence J.; Estroff, Lara A.

2017-01-01

Soft tissue-to-bone interfaces are complex structures that consist of gradients of extracellular matrix materials, cell phenotypes, and biochemical signals. These interfaces, called entheses for ligaments, tendons, and the meniscus, are crucial to joint function, transferring mechanical loads and stabilizing orthopedic joints. When injuries occur to connected soft tissue, the enthesis must be re-established to restore function, but due to structural complexity, repair has proven challenging. Tissue engineering offers a promising solution for regenerating these tissues. This prospective review discusses methodologies for tissue engineering the enthesis, outlined in three key design inputs: materials processing methods, cellular contributions, and biochemical factors. PMID:29333332

Small-Scale Fabrication of Biomimetic Structures for Periodontal Regeneration

PubMed Central

Green, David W.; Lee, Jung-Seok; Jung, Han-Sung

2016-01-01

The periodontium is the supporting tissues for the tooth organ and is vulnerable to destruction, arising from overpopulating pathogenic bacteria and spirochaetes. The presence of microbes together with host responses can destroy large parts of the periodontium sometimes leading tooth loss. Permanent tissue replacements are made possible with tissue engineering techniques. However, existing periodontal biomaterials cannot promote proper tissue architectures, necessary tissue volumes within the periodontal pocket and a “water-tight” barrier, to become clinically acceptable. New kinds of small-scale engineered biomaterials, with increasing biological complexity are needed to guide proper biomimetic regeneration of periodontal tissues. So the ability to make compound structures with small modules, filled with tissue components, is a promising design strategy for simulating the anatomical complexity of the periodotium attachment complexes along the tooth root and the abutment with the tooth collar. Anatomical structures such as, intima, adventitia, and special compartments such as the epithelial cell rests of Malassez or a stellate reticulum niche need to be engineered from the start of regeneration to produce proper periodontium replacement. It is our contention that the positioning of tissue components at the origin is also necessary to promote self-organizing cell–cell connections, cell–matrix connections. This leads to accelerated, synchronized and well-formed tissue architectures and anatomies. This strategy is a highly effective preparation for tackling periodontitis, periodontium tissue resorption, and to ultimately prevent tooth loss. Furthermore, such biomimetic tissue replacements will tackle problems associated with dental implant support and perimimplantitis. PMID:26903872

Collagenous Extracellular Matrix Biomaterials for Tissue Engineering: Lessons from the Common Sea Urchin Tissue.

PubMed

Goh, Kheng Lim; Holmes, David F

2017-04-25

Scaffolds for tissue engineering application may be made from a collagenous extracellular matrix (ECM) of connective tissues because the ECM can mimic the functions of the target tissue. The primary sources of collagenous ECM material are calf skin and bone. However, these sources are associated with the risk of having bovine spongiform encephalopathy or transmissible spongiform encephalopathy. Alternative sources for collagenous ECM materials may be derived from livestock, e.g., pigs, and from marine animals, e.g., sea urchins. Collagenous ECM of the sea urchin possesses structural features and mechanical properties that are similar to those of mammalian ones. However, even more intriguing is that some tissues such as the ligamentous catch apparatus can exhibit mutability, namely rapid reversible changes in the tissue mechanical properties. These tissues are known as mutable collagenous tissues (MCTs). The mutability of these tissues has been the subject of on-going investigations, covering the biochemistry, structural biology and mechanical properties of the collagenous components. Recent studies point to a nerve-control system for regulating the ECM macromolecules that are involved in the sliding action of collagen fibrils in the MCT. This review discusses the key attributes of the structure and function of the ECM of the sea urchin ligaments that are related to the fibril-fibril sliding action-the focus is on the respective components within the hierarchical architecture of the tissue. In this context, structure refers to size, shape and separation distance of the ECM components while function is associated with mechanical properties e.g., strength and stiffness. For simplicity, the components that address the different length scale from the largest to the smallest are as follows: collagen fibres, collagen fibrils, interfibrillar matrix and collagen molecules. Application of recent theories of stress transfer and fracture mechanisms in fibre reinforced composites to a wide variety of collagen reinforcing (non-mutable) connective tissue, has allowed us to draw general conclusions concerning the mechanical response of the MCT at specific mechanical states, namely the stiff and complaint states. The intent of this review is to provide the latest insights, as well as identify technical challenges and opportunities, that may be useful for developing methods for effective mechanical support when adapting decellularised connective tissues from the sea urchin for tissue engineering or for the design of a synthetic analogue.

Collagenous Extracellular Matrix Biomaterials for Tissue Engineering: Lessons from the Common Sea Urchin Tissue

PubMed Central

Goh, Kheng Lim; Holmes, David F.

2017-01-01

Scaffolds for tissue engineering application may be made from a collagenous extracellular matrix (ECM) of connective tissues because the ECM can mimic the functions of the target tissue. The primary sources of collagenous ECM material are calf skin and bone. However, these sources are associated with the risk of having bovine spongiform encephalopathy or transmissible spongiform encephalopathy. Alternative sources for collagenous ECM materials may be derived from livestock, e.g., pigs, and from marine animals, e.g., sea urchins. Collagenous ECM of the sea urchin possesses structural features and mechanical properties that are similar to those of mammalian ones. However, even more intriguing is that some tissues such as the ligamentous catch apparatus can exhibit mutability, namely rapid reversible changes in the tissue mechanical properties. These tissues are known as mutable collagenous tissues (MCTs). The mutability of these tissues has been the subject of on-going investigations, covering the biochemistry, structural biology and mechanical properties of the collagenous components. Recent studies point to a nerve-control system for regulating the ECM macromolecules that are involved in the sliding action of collagen fibrils in the MCT. This review discusses the key attributes of the structure and function of the ECM of the sea urchin ligaments that are related to the fibril-fibril sliding action—the focus is on the respective components within the hierarchical architecture of the tissue. In this context, structure refers to size, shape and separation distance of the ECM components while function is associated with mechanical properties e.g., strength and stiffness. For simplicity, the components that address the different length scale from the largest to the smallest are as follows: collagen fibres, collagen fibrils, interfibrillar matrix and collagen molecules. Application of recent theories of stress transfer and fracture mechanisms in fibre reinforced composites to a wide variety of collagen reinforcing (non-mutable) connective tissue, has allowed us to draw general conclusions concerning the mechanical response of the MCT at specific mechanical states, namely the stiff and complaint states. The intent of this review is to provide the latest insights, as well as identify technical challenges and opportunities, that may be useful for developing methods for effective mechanical support when adapting decellularised connective tissues from the sea urchin for tissue engineering or for the design of a synthetic analogue. PMID:28441344

Effect of age on structural properties of intramuscular connective tissue, muscle fibre, collagen content and meat tenderness in pig longissimus lumborum muscle.

PubMed

Wojtysiak, Dorota

2013-01-01

Changes in the structure and properties of the intramuscular connective tissue, muscle fibre size, collagen content and meat tenderness of m. longissimus lumborum during growth was studied in 45 Polish Large White (PLW) pigs slaughtered at 90, 150 and 210 days of age. The results show that the endomysial sheath in m. longissimus lumborum consists of collagen fibrils of wavy appearance which run in all directions and form a loose network. The arrangement of collagen fibrils in the endomysium and perimysium becomes denser and more regular with increasing age of pigs. In addition, the increase in endomysium and perimysium thickness was paralleled by a significant increase in muscle fibre diameter, as well as an increase in shear force value with chronological aging. In contrast, the percentage of collagen area in muscle structure and the amount of total collagen and amount of soluble collagen decreased gradually with age of pigs. In conclusion, the structural changes in the arrangement of collagen fibres in the architecture of intramusclular connective tissue, as well as the decrease in soluble collagen content in m. longissimus lumborum during growth of pigs are important factors influencing shear force value, and thus raw meat tenderness.

Kidney biopsy

MedlinePlus

... normal structure. What Abnormal Results Mean An abnormal result means there are changes in the kidney tissue. This may be due to: Infection Poor blood flow through the kidney Connective tissue diseases such as systemic lupus erythematosus Other diseases that may be affecting the ...

Application of biospeckles for assessment of structural and cellular changes in muscle tissue

NASA Astrophysics Data System (ADS)

Maksymenko, Oleksandr P.; Muravsky, Leonid I.; Berezyuk, Mykola I.

2015-09-01

A modified spatial-temporal speckle correlation technique for operational assessment of structural changes in muscle tissues after slaughtering is considered. Coefficient of biological activity as a quantitative indicator of structural changes of biochemical processes in biological tissues is proposed. The experimental results have shown that this coefficient properly evaluates the biological activity of pig and chicken muscle tissue samples. Studying the degradation processes in muscle tissue during long-time storage in a refrigerator by measuring the spatial-temporal dynamics of biospeckle patterns is carried out. The reduction of the bioactivity level of refrigerated muscle tissue samples connected with the initiation of muscle fiber cracks and ruptures, reduction of sarcomeres, nuclei deformation, nuclear chromatin diminishing, and destruction of mitochondria is analyzed.

Connective tissue regeneration in skeletal muscle after eccentric contraction-induced injury.

PubMed

Mackey, Abigail L; Kjaer, Michael

2017-03-01

Human skeletal muscle has the potential to regenerate completely after injury induced under controlled experimental conditions. The events inside the myofibers as they undergo necrosis, followed closely by satellite cell-mediated myogenesis, have been mapped in detail. Much less is known about the adaptation throughout this process of both the connective tissue structures surrounding the myofibers and the fibroblasts, the cells responsible for synthesizing this connective tissue. However, the few studies investigating muscle connective tissue remodeling demonstrate a strong response that appears to be sustained for a long time after the major myofiber responses have subsided. While the use of electrical stimulation to induce eccentric contractions vs. voluntary eccentric contractions appears to lead to a greater extent of myofiber necrosis and regenerative response, this difference is not apparent when the muscle connective tissue responses are compared, although further work is required to confirm this. Pharmacological agents (growth hormone and angiotensin II type I receptor blockers) are considered in the context of accelerating the muscle connective tissue adaptation to loading. Cautioning against this, however, is the association between muscle matrix protein remodeling and protection against reinjury, which suggests that a (so far undefined) period of vulnerability to reinjury may exist during the remodeling phases. The role of individual muscle matrix components and their spatial interaction during adaptation to eccentric contractions is an unexplored field in human skeletal muscle and may provide insight into the optimal timing of rest vs. return to activity after muscle injury. Copyright © 2017 the American Physiological Society.

Soft tissue wound healing around teeth and dental implants.

PubMed

Sculean, Anton; Gruber, Reinhard; Bosshardt, Dieter D

2014-04-01

To provide an overview on the biology and soft tissue wound healing around teeth and dental implants. This narrative review focuses on cell biology and histology of soft tissue wounds around natural teeth and dental implants. The available data indicate that: (a) Oral wounds follow a similar pattern. (b) The tissue specificities of the gingival, alveolar and palatal mucosa appear to be innately and not necessarily functionally determined. (c) The granulation tissue originating from the periodontal ligament or from connective tissue originally covered by keratinized epithelium has the potential to induce keratinization. However, it also appears that deep palatal connective tissue may not have the same potential to induce keratinization as the palatal connective tissue originating from an immediately subepithelial area. (d) Epithelial healing following non-surgical and surgical periodontal therapy appears to be completed after a period of 7–14 days. Structural integrity of a maturing wound between a denuded root surface and a soft tissue flap is achieved at approximately 14-days post-surgery. (e) The formation of the biological width and maturation of the barrier function around transmucosal implants requires 6–8 weeks of healing. (f) The established peri-implant soft connective tissue resembles a scar tissue in composition, fibre orientation, and vasculature. (g) The peri-implant junctional epithelium may reach a greater final length under certain conditions such as implants placed into fresh extraction sockets versus conventional implant procedures in healed sites. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Glycosaminoglycans and fibrillar collagen in Priapulida: a histo- and cytochemical study.

PubMed

Welsch, U; Erlinger, R; Storch, V

1992-12-01

The distribution of glycosaminoglycans and fibrillar collagen was studied in various tissues of priapulids, which represent an ancient group of marine metazoa. Sulphated glycosaminoglycans, as demonstrated at the electron microscopical level by Cupromeronic blue, were predominantly found in the cuticle, in basement membranes and also in the narrow connective tissue space below epidermis and anterior intestine. On the basis of their morphology the Cupromeronic blue precipitates could be divided into several groups. Fibrillar collagen occurred in the connective tissue under the epidermis and the epithelium of the anterior intestine. The spatial interrelationship between fibrillar collagen and glycosaminoglycans lacked with some exceptions, the high regularity found in connective tissues of other invertebrates and of vertebrates. This might be related to the special skeletal system of priapulids, consisting mainly of a strong extracellular cuticle and the turgor of the fluid-filled body cavity. In such a system the usual supportive structures seem to be of less functional significance.

Translational MR Neuroimaging of Stroke and Recovery

PubMed Central

Mandeville, Emiri T.; Ayata, Cenk; Zheng, Yi; Mandeville, Joseph B.

2016-01-01

Multiparametric magnetic resonance imaging (MRI) has become a critical clinical tool for diagnosing focal ischemic stroke severity, staging treatment, and predicting outcome. Imaging during the acute phase focuses on tissue viability in the stroke vicinity, while imaging during recovery requires the evaluation of distributed structural and functional connectivity. Preclinical MRI of experimental stroke models provides validation of non-invasive biomarkers in terms of cellular and molecular mechanisms, while also providing a translational platform for evaluation of prospective therapies. This brief review of translational stroke imaging discusses the acute to chronic imaging transition, the principles underlying common MRI methods employed in stroke research, and experimental results obtained by clinical and preclinical imaging to determine tissue viability, vascular remodeling, structural connectivity of major white matter tracts, and functional connectivity using task-based and resting-state fMRI during the stroke recovery process. PMID:27578048

Histologic analysis of the acellular dermal matrix graft incorporation process: a pilot study in dogs.

PubMed

Luczyszyn, Sonia M; Grisi, Márcio F M; Novaes, Arthur B; Palioto, Daniela B; Souza, Sérgio L S; Taba, Mario

2007-08-01

Clinical results with acellular dermal matrix graft (ADMG) in periodontal surgeries suggest that the material is incorporated by the host tissues. However, histologic studies of the ADMG incorporation process are limited. The objective of this study was to evaluate the incorporation of ADMG into gingival tissues in a dog model. Gingival recession-type defects were created at the canines of six dogs. After 6 weeks, periodontal surgeries to repair the defects were performed using ADMG. Two animals each were sacrificed after 4, 8, and 12 weeks. At 4 weeks, thick collagen fibers from the ADMG were clearly seen in the connective tissue, and some blood vessels were penetrating into the ADMG. At 8 weeks, blood vessel penetration was enhanced, and collagen fiber bundles from the ADMG were seen sending branches into the connective tissue in all directions. After 12 weeks, the ADMG and the connective tissue seemed to be well integrated into a single highly vascularized structure, indicating almost complete incorporation of the ADMG.

Causal effect of disconnection lesions on interhemispheric functional connectivity in rhesus monkeys

PubMed Central

O’Reilly, Jill X.; Croxson, Paula L.; Jbabdi, Saad; Sallet, Jerome; Noonan, MaryAnn P.; Mars, Rogier B.; Browning, Philip G.F.; Wilson, Charles R. E.; Mitchell, Anna S.; Miller, Karla L.; Rushworth, Matthew F. S.; Baxter, Mark G.

2013-01-01

In the absence of external stimuli or task demands, correlations in spontaneous brain activity (functional connectivity) reflect patterns of anatomical connectivity. Hence, resting-state functional connectivity has been used as a proxy measure for structural connectivity and as a biomarker for brain changes in disease. To relate changes in functional connectivity to physiological changes in the brain, it is important to understand how correlations in functional connectivity depend on the physical integrity of brain tissue. The causal nature of this relationship has been called into question by patient data suggesting that decreased structural connectivity does not necessarily lead to decreased functional connectivity. Here we provide evidence for a causal but complex relationship between structural connectivity and functional connectivity: we tested interhemispheric functional connectivity before and after corpus callosum section in rhesus monkeys. We found that forebrain commissurotomy severely reduced interhemispheric functional connectivity, but surprisingly, this effect was greatly mitigated if the anterior commissure was left intact. Furthermore, intact structural connections increased their functional connectivity in line with the hypothesis that the inputs to each node are normalized. We conclude that functional connectivity is likely driven by corticocortical white matter connections but with complex network interactions such that a near-normal pattern of functional connectivity can be maintained by just a few indirect structural connections. These surprising results highlight the importance of network-level interactions in functional connectivity and may cast light on various paradoxical findings concerning changes in functional connectivity in disease states. PMID:23924609

Effects of long-duration bed rest on structural compartments of m. soleus in man

NASA Technical Reports Server (NTRS)

Belozerova, I.; Shenkman, B.; Mazin, M.; Leblanc, A.; LeBlanc, A. D. (Principal Investigator)

2001-01-01

Magnetic resonance imaging (MRI), histomorphometry and electron microscopy of muscle demonstrate that long-term exposure to actual or simulated weightlessness (including head down bed rest) leads to decreased volume of antigravity muscles in mammals. In muscles interbundle space is occupied by the connective tissue. Rat studies show that hindlimb unloading induces muscle fiber atrophy along with increase in muscle non-fiber connective tissue compartment. Beside that, usually 20% of the muscle fiber volume is comprised by non-contractile (non-myofibrillar) compartment. The aim of the present study was to compare changes in muscle volume, and in muscle fiber size with alterations in myofibrillar apparatus, and in connective tissue compartment in human m. soleus under conditions of 120 day long head down bed rest (HDBR).

Effects of protein-coated nanofibers on conformation of gingival fibroblast spheroids: potential utility for connective tissues regeneration.

PubMed

Kaufman, Gili; Whitescarver, Ryan; Nunes, Laiz; Palmer, Xavier-Lewis; Skrtic, Drago; Tutak, Wojtek

2017-10-09

Deep wounds in the gingiva caused by trauma or surgery require a rapid and robust healing of connective tissues. We propose utilizing gas-brushed nanofibers coated with collagen and fibrin for that purpose. Our hypotheses are that protein-coated nanofibers will: (i) attract and mobilize cells in various spatial orientations, and (ii) regulate the expression levels of specific extracellular matrix (ECM)-associated proteins, determining the initial conformational nature of dense and soft connective tissues. Gingival fibroblast monolayers and 3D spheroids were cultured on ECM substrate and covered with gas-blown poly-(DL-lactide-co-glycolide) (PLGA) nanofibers (uncoated/coated with collagen and fibrin). Cell attraction and rearrangement was followed by F-actin staining and confocal microscopy. Thicknesses of the cell layers, developed within the nanofibers, were quantified by imageJ software. The expression of collagen1α1 chain (Col1α1), fibronectin, and metalloproteinase 2 (MMP2) encoding genes was determined by quantitative reverse transcription analysis. Collagen- and fibrin- coated nanofibers induced cell migration toward fibers and supported cellular growth within the scaffolds. Both proteins affected the spatial rearrangement of fibroblasts by favoring packed cell clusters or intermittent cell spreading. These cell arrangements resembled the structural characteristic of dense and soft connective tissues, respectively. Within 3 days of incubation, fibroblast spheroids interacted with the fibers and grew robustly by increasing their thickness compared to monolayers. While the ECM key components, such as fibronectin and MMP2 encoding genes, were expressed in both protein groups, Col1α1 was predominantly expressed in bundled fibroblasts grown on collagen fibers. This enhanced expression of collagen1 is typical for dense connective tissue. Based on results of this study, our gas-blown, collagen- and fibrin-coated PLGA nanofibers are viable candidates for engineering soft and dense connective tissues with the required structural characteristics and functions needed for wound healing applications. Rapid regeneration of these layers should enhance healing of open wounds in a harsh oral environment. © 2017 IOP Publishing Ltd.

A molecular ensemble in the rER for procollagen maturation.

PubMed

Ishikawa, Yoshihiro; Bächinger, Hans Peter

2013-11-01

Extracellular matrix (ECM) proteins create structural frameworks in tissues such as bone, skin, tendon and cartilage etc. These connective tissues play important roles in the development and homeostasis of organs. Collagen is the most abundant ECM protein and represents one third of all proteins in humans. The biosynthesis of ECM proteins occurs in the rough endoplasmic reticulum (rER). This review describes the current understanding of the biosynthesis and folding of procollagens, which are the precursor molecules of collagens, in the rER. Multiple folding enzymes and molecular chaperones are required for procollagen to establish specific posttranslational modifications, and facilitate folding and transport to the cell surface. Thus, this molecular ensemble in the rER contributes to ECM maturation and to the development and homeostasis of tissues. Mutations in this ensemble are likely candidates for connective tissue disorders. This article is part of a Special Issue entitled: Functional and structural diversity of endoplasmic reticulum. Copyright © 2013 Elsevier B.V. All rights reserved.

The connective tissue phenotype of glaucomatous cupping in the monkey eye - Clinical and research implications.

PubMed

Yang, Hongli; Reynaud, Juan; Lockwood, Howard; Williams, Galen; Hardin, Christy; Reyes, Luke; Stowell, Cheri; Gardiner, Stuart K; Burgoyne, Claude F

2017-07-01

In a series of previous publications we have proposed a framework for conceptualizing the optic nerve head (ONH) as a biomechanical structure. That framework proposes important roles for intraocular pressure (IOP), IOP-related stress and strain, cerebrospinal fluid pressure (CSFp), systemic and ocular determinants of blood flow, inflammation, auto-immunity, genetics, and other non-IOP related risk factors in the physiology of ONH aging and the pathophysiology of glaucomatous damage to the ONH. The present report summarizes 20 years of technique development and study results pertinent to the characterization of ONH connective tissue deformation and remodeling in the unilateral monkey experimental glaucoma (EG) model. In it we propose that the defining pathophysiology of a glaucomatous optic neuropathy involves deformation, remodeling, and mechanical failure of the ONH connective tissues. We view this as an active process, driven by astrocyte, microglial, fibroblast and oligodendrocyte mechanobiology. These cells, and the connective tissue phenomena they propagate, have primary and secondary effects on retinal ganglion cell (RGC) axon, laminar beam and retrolaminar capillary homeostasis that may initially be "protective" but eventually lead to RGC axonal injury, repair and/or cell death. The primary goal of this report is to summarize our 3D histomorphometric and optical coherence tomography (OCT)-based evidence for the early onset and progression of ONH connective tissue deformation and remodeling in monkey EG. A second goal is to explain the importance of including ONH connective tissue processes in characterizing the phenotype of a glaucomatous optic neuropathy in all species. A third goal is to summarize our current efforts to move from ONH morphology to the cell biology of connective tissue remodeling and axonal insult early in the disease. A final goal is to facilitate the translation of our findings and ideas into neuroprotective interventions that target these ONH phenomena for therapeutic effect. Copyright © 2017 Elsevier Ltd. All rights reserved.

The muscular force transmission system: role of the intramuscular connective tissue.

PubMed

Turrina, Andrea; Martínez-González, Miguel Antonio; Stecco, Carla

2013-01-01

The objective of this review is to analyze in detail the microscopic structure and relations among muscular fibers, endomysium, perimysium, epimysium and deep fasciae. In particular, the multilayer organization and the collagen fiber orientation of these elements are reported. The endomysium, perimysium, epimysium and deep fasciae have not just a role of containment, limiting the expansion of the muscle with the disposition in concentric layers of the collagen tissue, but are fundamental elements for the transmission of muscular force, each one with a specific role. From this review it appears that the muscular fibers should not be studied as isolated elements, but as a complex inseparable from their fibrous components. The force expressed by a muscle depends not only on its anatomical structure, but also the angle at which its fibers are attached to the intramuscular connective tissue and the relation with the epimysium and deep fasciae. Copyright © 2012 Elsevier Ltd. All rights reserved.

Celebration of the 50th anniversary of the foundation of the French society for connective tissue research. Its short history in the frame of the origin and development of this discipline.

PubMed

Borel, J P; Maquart, F X; Robert, A M; Labat-Robert, J; Robert, L

2012-02-01

The science of connective tissues has (at least) a double origin. Collagen, their major constituent was first studied in conjunction with the leather industry. Acid mucopolysaccharides (now glycosaminoglycans) were characterised by (bio)-chemists interested in glycoconjugates. They joined mainly hospital-based rheumatology departments. Later started the study of elastin with the discovery of elastases and of connective tissue-born (structural) glycoproteins. Besides rhumatologists and leather-chemists mainly pathologists became involved in this type of research, followed closely by ophthalmology research. The first important meetings of these diverse specialists were organised under the auspices of NATO, first in Saint-Andrew's in GB in 1964 and a few years later (1969) in Santa Margareta, Italy. With the discovery of fibronectin, a "structural glycoprotein", started the study of cell-matrix interactions, reinforced by the identification of cell-receptors mediating them and the "cross-talk" between cells and matrix constituents. The first initiative to organise societies for this rapidly growing discipline was that of Ward Pigman in New York in 1961, restricted however to glycol-conjugates. Next year, in 1962 was founded the first European Connective Tissue Society in Paris: the "Club français du tissu conjonctif", which played a crucial role in the establishment of schools, laboratories, national and international meetings in the major cities of France: Paris, Lyon, Reims, Caen,Toulouse. A second European society was born in Great Britain, and at a joint meeting with the French society at the Paris Pasteur Institute, was founded in 1967 by these societies the Federation of European Connective Tissue Societies (FECTS). Their meetings, organised every second year, drained a wide attendance from all over the world. An increasing number of young scientists joined since then this branch of biomedical discipline with several international journals devoted to connective tissue research, to matrix biology. The increasing number and quality of the young generation of scientists engaged in research related to the extracellular matrix or better Biomatrix and cell-matrix interactions is a further guarantee for the continued interest in this crucial field of science at the interface of basic and medically oriented research. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

[Observation and analysis on the meridian-collateral running track-related anatomical structure in the human body].

PubMed

Xie, Hao-ran; Li, Fang-chun; Zhang, Wei-bo

2009-06-01

In the present paper the authors analyze the anatomical structure of the meridian running track by using the dialectical thought and comprehensive analysis of the integrated Chinese and western medicine. It has been observed that the "Qi-passages" of the 14 meridians of Chinese medicine are located in the connective tissue among the interspace of the muscles, etc. distributing longitudinally. The "Qi-passages" of the 15 Luomai (collaterals of the meridians) are located in the connective tissue among the interspace of the muscles, etc. distributing transversally, while those of the small branches of the meridian collaterals are located in the interspace mesenchyme of the muscle bundles distributing in the whole body. The "Qi-passages" of the tiny branches of the meridian collaterals are located in the mesenchyme of the intracellular space, such as the muscle fibers in the whole body. The authors hold that the so-called "Mai Qi" of the meridian-collaterals is the liquid-Qi flowing in the vertical and horizontal tissue interspaces. The "Qi-passage" of the meridian-collaterals of Chinese medicine is the pathway of the liquid-Qi of the tissue interspaces. The structure of the meridian-collaterals is the tissue interspace. The meridian-collateral system is a regulation-control system in the human body where the Qi-passages communicate with each other, and is, in fact, the protoplasm, the liquid-Qi circulating in the tissue interspaces.

A New Modeling for the Changes in the Distribution of Scatterers in Cirrhotic Liver

NASA Astrophysics Data System (ADS)

Hara, Takashi; Hachiya, Hiroyuki

2000-05-01

The human liver is composed of small hexagonal structures called liver lobules. Cirrhosis destroys these liver lobules and replaces them with permanent connective tissue referred to as regenerative nodules. In this paper, we propose a new modeling technique for changes in the scatterer distribution in liver tissue considering the structure of liver lobules to obtain images of the cirrhotic liver over continuous stages. Using these images, we analyze the relationship between changes in characteristics of biological tissue and changes in B-mode images during progressive liver cirrhosis.

Ultrastructural and biochemical characterization of mechanically adaptable collagenous structures in the edible sea urchin Paracentrotus lividus.

PubMed

Barbaglio, Alice; Tricarico, Serena; Ribeiro, Ana R; Di Benedetto, Cristiano; Barbato, Marta; Dessì, Desirèe; Fugnanesi, Valeria; Magni, Stefano; Mosca, Fabio; Sugni, Michela; Bonasoro, Francesco; Barbosa, Mario A; Wilkie, Iain C; Candia Carnevali, M Daniela

2015-06-01

The viscoelastic properties of vertebrate connective tissues rarely undergo significant changes within physiological timescales, the only major exception being the reversible destiffening of the mammalian uterine cervix at the end of pregnancy. In contrast to this, the connective tissues of echinoderms (sea urchins, starfish, sea cucumbers, etc.) can switch reversibly between stiff and compliant conditions in timescales of around a second to minutes. Elucidation of the molecular mechanism underlying such mutability has implications for the zoological, ecological and evolutionary field. Important information could also arise for veterinary and biomedical sciences, particularly regarding the pathological plasticization or stiffening of connective tissue structures. In the present investigation we analyzed aspects of the ultrastructure and biochemistry in two representative models, the compass depressor ligament and the peristomial membrane of the edible sea urchin Paracentrotus lividus, compared in three different mechanical states. The results provide further evidence that the mechanical adaptability of echinoderm connective tissues does not necessarily imply changes in the collagen fibrils themselves. The higher glycosaminoglycan (GAG) content registered in the peristomial membrane with respect to the compass depressor ligament suggests a diverse role of these molecules in the two mutable collagenous tissues. The possible involvement of GAG in the mutability phenomenon will need further clarification. During the shift from a compliant to a standard condition, significant changes in GAG content were detected only in the compass depressor ligament. Similarities in terms of ultrastructure (collagen fibrillar assembling) and biochemistry (two alpha chains) were found between the two models and mammalian collagen. Nevertheless, differences in collagen immunoreactivity, alpha chain migration on SDS-PAGE and BLAST alignment highlighted the uniqueness of sea urchin collagen with respect to mammalian collagen. Copyright © 2015 Elsevier GmbH. All rights reserved.

Syringe Injectable Electronics: Precise Targeted Delivery with Quantitative Input/Output Connectivity.

PubMed

Hong, Guosong; Fu, Tian-Ming; Zhou, Tao; Schuhmann, Thomas G; Huang, Jinlin; Lieber, Charles M

2015-10-14

Syringe-injectable mesh electronics with tissue-like mechanical properties and open macroporous structures is an emerging powerful paradigm for mapping and modulating brain activity. Indeed, the ultraflexible macroporous structure has exhibited unprecedented minimal/noninvasiveness and the promotion of attractive interactions with neurons in chronic studies. These same structural features also pose new challenges and opportunities for precise targeted delivery in specific brain regions and quantitative input/output (I/O) connectivity needed for reliable electrical measurements. Here, we describe new results that address in a flexible manner both of these points. First, we have developed a controlled injection approach that maintains the extended mesh structure during the "blind" injection process, while also achieving targeted delivery with ca. 20 μm spatial precision. Optical and microcomputed tomography results from injections into tissue-like hydrogel, ex vivo brain tissue, and in vivo brains validate our basic approach and demonstrate its generality. Second, we present a general strategy to achieve up to 100% multichannel I/O connectivity using an automated conductive ink printing methodology to connect the mesh electronics and a flexible flat cable, which serves as the standard "plug-in" interface to measurement electronics. Studies of resistance versus printed line width were used to identify optimal conditions, and moreover, frequency-dependent noise measurements show that the flexible printing process yields values comparable to commercial flip-chip bonding technology. Our results address two key challenges faced by syringe-injectable electronics and thereby pave the way for facile in vivo applications of injectable mesh electronics as a general and powerful tool for long-term mapping and modulation of brain activity in fundamental neuroscience through therapeutic biomedical studies.

Ultrastructural organization of connective tissue microfibrils in the posterior chamber of the eye in vivo and in vitro.

PubMed

Inoue, S

1995-02-01

The ultrastructural organization of connective tissue microfibrils was studied in the mouse eye and also by means of in vitro experiments for reconstituting microfibrils. In the posterior chamber of the eye of the C57BL/6J mouse, 3 nm-wide ribbon-like double-tracked structures were present and were periodically associated on either side with 3.5 nm-wide particulate structures identified as pentosomes, the subunits of amyloid P component (AP). At certain sites, such composite structures were observed in various stages of helical winding, and in these helices, pentosomes were preferentially localized internally. In helices in the final stages of winding, the resulting rods appeared increasingly similar to those of microfibrils. In experiments in vitro, incubation of chondroitin sulfate proteoglycan (CSPG) in TRIS buffer, pH 7.4, at 35 degrees C for 1 h produced random aggregates of 3 nm-wide double-tracked structures similar to those observed in the eye. Co-incubation of CSPG and AP resulted in the formation of rod-like structures arranged parallel to one another in approximately 50 nm-thick sheet-like layers. These rods were ultrastructurally similar to microfibrils and were made up of helically wound, 3 nm-wide double-tracked structures containing pentosomes within their core. The results of in vivo as well as in vitro experiments suggest the possibility that the connective tissue microfibril is composed of helically wound, CSPG-containing, 3 nm-wide double-tracked structures periodically associated with pentosomes which, as the helix becomes progressively tighter, fit with one another at the core of the helix to form successive 8.5 nm-wide disks of AP segments.

Zebrafish collagen XII is present in embryonic connective tissue sheaths (fascia) and basement membranes.

PubMed

Bader, Hannah L; Keene, Douglas R; Charvet, Benjamin; Veit, Guido; Driever, Wolfgang; Koch, Manuel; Ruggiero, Florence

2009-01-01

Connective tissues ensure the cohesion of the tissues of the body, but also form specialized structures such as tendon and bone. Collagen XII may enhance the stability of connective tissues by bridging collagen fibrils, but its function is still unclear. Here, we used the zebrafish model to visualize its expression pattern in the whole organism. The zebrafish col12a1 gene is homologous to the small isoform of the tetrapod col12a1 gene. In agreement with the biochemical data reported for the small isoform, the zebrafish collagen XII alpha1 chain was characterized as a collagenase sensitive band migrating at approximately 200 kDa. Using newly generated polyclonal antibodies and anti-sense probes, we performed a comprehensive analysis of its expression in developing zebrafish. Collagen XII exhibited a much broader expression pattern than previously thought: it was ubiquitously expressed in the connective tissue sheaths (fascia) that encase the tissues and organs of the body. For example, it was found in sclera, meninges, epimysia and horizontal and vertical myosepta. Collagen XII was also detected in head mesenchyme, pharyngeal arches and within the spinal cord, where it was first expressed within and then at the lateral borders of the floor plate and at the dorsal midline. Furthermore, double immunofluorescence staining with laminin and immunogold electron microscopy revealed that collagen XII is associated with basement membranes. These data suggest that collagen XII is implicated in tissue cohesion by stabilizing fascia and by linking fascia to basement membranes.

Hematopoietic stem cell origin of connective tissues.

PubMed

Ogawa, Makio; Larue, Amanda C; Watson, Patricia M; Watson, Dennis K

2010-07-01

Connective tissue consists of "connective tissue proper," which is further divided into loose and dense (fibrous) connective tissues and "specialized connective tissues." Specialized connective tissues consist of blood, adipose tissue, cartilage, and bone. In both loose and dense connective tissues, the principal cellular element is fibroblasts. It has been generally believed that all cellular elements of connective tissue, including fibroblasts, adipocytes, chondrocytes, and bone cells, are generated solely by mesenchymal stem cells. Recently, a number of studies, including those from our laboratory based on transplantation of single hematopoietic stem cells, strongly suggested a hematopoietic stem cell origin of these adult mesenchymal tissues. This review summarizes the experimental evidence for this new paradigm and discusses its translational implications. Copyright 2010 ISEH - Society for Hematology and Stem Cells. All rights reserved.

Pathological changes in the subsynovial connective tissue increase with self-reported carpal tunnel syndrome symptoms.

PubMed

Tat, Jimmy; Wilson, Katherine E; Keir, Peter J

2015-05-01

Fibrosis and thickening of the subysnovial connective tissue are the most common pathological findings in carpal tunnel syndrome. The relationship between subsynovial connective tissue characteristics and self-reported carpal tunnel syndrome symptoms was assessed. Symptoms were characterized using the Boston Carpal Tunnel Questionnaire and Katz hand diagram in twenty-two participants (11 with symptoms, 11 with no symptoms). Using ultrasound, the thickness of the subsynovial connective tissue was measured using a thickness ratio (subsynovial thickness/tendon thickness) and gliding function was assessed using a shear strain index ((Displacement(tendon)-Displacement(subsynovial))/Displacement(tendon)x 100). For gliding function, participants performed 10 repeated flexion-extension cycles of the middle finger at a rate of one cycle per second. Participants with symptoms had a 38.5% greater thickness ratio and 39.2% greater shear strain index compared to participants without symptoms (p<0.05). Ultrasound detected differences the SSCT in symptomatic group that was characterized by low self-reported symptom severity scores. This study found ultrasound useful for measuring structural and functional changes in the SSCT that could provide insight in the early pathophysiology associated with carpal tunnel syndrome symptoms. Copyright © 2015 Elsevier Ltd. All rights reserved.

Basic components of connective tissues and extracellular matrix: elastin, fibrillin, fibulins, fibrinogen, fibronectin, laminin, tenascins and thrombospondins.

PubMed

Halper, Jaroslava; Kjaer, Michael

2014-01-01

Collagens are the most abundant components of the extracellular matrix and many types of soft tissues. Elastin is another major component of certain soft tissues, such as arterial walls and ligaments. Many other molecules, though lower in quantity, function as essential 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 muldomain 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. Laminins contribute to the structure of the extracellular matrix (ECM) and modulate cellular functions such as adhesion, differentiation, migration, stability of phenotype, and resistance towards apoptosis. 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. Elastin, an insoluble polymer of the monomeric soluble precursor tropoelastin, is 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 TGFβs 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. Fibrillins represent the predominant core of the 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 a scaffold 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. Fibulins are tightly connected with basement membranes, elastic fibers and other components of extracellular matrix and participate in formation of elastic fibers. 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 TGFβ. Increased expression of thrombospondin and TGFβ 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.

Information generation and processing systems that regulate periodontal structure and function.

PubMed

Bartold, P Mark; McCulloch, Christopher A

2013-10-01

The periodontium is a very dynamic organ that responds rapidly to mechanical and chemical stimuli. It is very complex in that it is composed of two hard tissues (cementum and bone) and two soft connective tissues (periodontal ligament and gingiva). Together these tissues are defined by the molecules expressed by the resident periodontal cells in each compartment and this determines not only the structure and function of the periodontium but also how it responds to infection and inflammation. The biological activity of these molecules is tightly regulated in time and space to preserve tissue homeostasis, influence inflammatory responses and participate in tissue regeneration. In this issue of Periodontology 2000 we explore new experimental approaches and data sets which help to understand the molecules and cells that regulate tissue form and structure in health, disease and regeneration. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Connective Tissue Growth Factor Is Involved in Structural Retinal Vascular Changes in Long-Term Experimental Diabetes

PubMed Central

Van Geest, Rob J.; Leeuwis, Jan Willem; Dendooven, Amélie; Pfister, Frederick; Bosch, Klazien; Hoeben, Kees A.; Vogels, Ilse M.C.; Van der Giezen, Dionne M.; Dietrich, Nadine; Hammes, Hans-Peter; Goldschmeding, Roel; Klaassen, Ingeborg; Van Noorden, Cornelis J.F.

2014-01-01

Early retinal vascular changes in the development of diabetic retinopathy (DR) include capillary basal lamina (BL) thickening, pericyte loss and the development of acellular capillaries. Expression of the CCN (connective tissue growth factor/cysteine-rich 61/nephroblastoma overexpressed) family member CCN2 or connective tissue growth factor (CTGF), a potent inducer of the expression of BL components, is upregulated early in diabetes. Diabetic mice lacking one functional CTGF allele (CTGF+/−) do not show this BL thickening. As early events in DR may be interrelated, we hypothesized that CTGF plays a role in the pathological changes of retinal capillaries other than BL thickening. We studied the effects of long-term (6-8 months) streptozotocin-induced diabetes on retinal capillary BL thickness, numbers of pericytes and the development of acellular capillaries in wild type and CTGF+/− mice. Our results show that an absence of BL thickening of retinal capillaries in long-term diabetic CTGF+/− mice is associated with reduced pericyte dropout and reduced formation of acellular capillaries. We conclude that CTGF is involved in structural retinal vascular changes in diabetic rodents. Inhibition of CTGF in the eye may therefore be protective against the development of DR. PMID:24217924

The universal existence of myodural bridge in mammals: an indication of a necessary function.

PubMed

Zheng, Nan; Yuan, Xiao-Ying; Chi, Yan-Yan; Liu, Pei; Wang, Bing; Sui, Jia-Ying; Han, Seung-Ho; Yu, Sheng-Bo; Sui, Hong-Jin

2017-08-15

The "myodural bridge" was described in literatures as a dense fibrous tissue connecting the sub-occipital musculature with the spinal dura mater in human studies. Now the concept of "myodural bridge" was perceived as an exact anatomical structure presumably essential for critical physiological functions in human body, and might exist in other mammals as well. To determine the existence of the "myodural bridge" in other mammals and to lay a foundation for the functional study, we examined representatives in five different mammalian orders. Based on the anatomical dissections, P45 plastinated sections and histological sections, we found that a dense fibrous tissue connected the rectus capitisdorsalis minor and the spinal dura mater through the dorsal atlanto-occipital interspace with or without the medium of the posterior atlanto-occipital membrane. These observed connective tissues were very similar to the "myodural bridge" previously described in humans. We proposed that the "myodural bridge", as an evolutionally conserved structure, presents in many other mammals. Moreover, we believed that the "myodural bridge" might be a homologous organ in mammals. Thus, this study could provide an insight for our understanding the physiological significance of the "myodural bridge", especially in human.

An overview of inverted colloidal crystal systems for tissue engineering.

PubMed

João, Carlos Filipe C; Vasconcelos, Joana Marta; Silva, Jorge Carvalho; Borges, João Paulo

2014-10-01

Scaffolding is at the heart of tissue engineering but the number of techniques available for turning biomaterials into scaffolds displaying the features required for a tissue engineering application is somewhat limited. Inverted colloidal crystals (ICCs) are inverse replicas of an ordered array of monodisperse colloidal particles, which organize themselves in packed long-range crystals. The literature on ICC systems has grown enormously in the past 20 years, driven by the need to find organized macroporous structures. Although replicating the structure of packed colloidal crystals (CCs) into solid structures has produced a wide range of advanced materials (e.g., photonic crystals, catalysts, and membranes) only in recent years have ICCs been evaluated as devices for medical/pharmaceutical and tissue engineering applications. The geometry, size, pore density, and interconnectivity are features of the scaffold that strongly affect the cell environment with consequences on cell adhesion, proliferation, and differentiation. ICC scaffolds are highly geometrically ordered structures with increased porosity and connectivity, which enhances oxygen and nutrient diffusion, providing optimum cellular development. In comparison to other types of scaffolds, ICCs have three major unique features: the isotropic three-dimensional environment, comprising highly uniform and size-controllable pores, and the presence of windows connecting adjacent pores. Thus far, this is the only technique that guarantees these features with a long-range order, between a few nanometers and thousands of micrometers. In this review, we present the current development status of ICC scaffolds for tissue engineering applications.

Deformation micromechanisms of collagen fibrils under uniaxial tension

PubMed Central

Tang, Yuye; Ballarini, Roberto; Buehler, Markus J.; Eppell, Steven J.

2010-01-01

Collagen, an essential building block of connective tissues, possesses useful mechanical properties due to its hierarchical structure. However, little is known about the mechanical properties of collagen fibril, an intermediate structure between the collagen molecule and connective tissue. Here, we report the results of systematic molecular dynamics simulations to probe the mechanical response of initially unflawed finite size collagen fibrils subjected to uniaxial tension. The observed deformation mechanisms, associated with rupture and sliding of tropocollagen molecules, are strongly influenced by fibril length, width and cross-linking density. Fibrils containing more than approximately 10 molecules along their length and across their width behave as representative volume elements and exhibit brittle fracture. Shorter fibrils experience a more graceful ductile-like failure. An analytical model is constructed and the results of the molecular modelling are used to find curve-fitted expressions for yield stress, yield strain and fracture strain as functions of fibril structural parameters. Our results for the first time elucidate the size dependence of mechanical failure properties of collagen fibrils. The associated molecular deformation mechanisms allow the full power of traditional material and structural engineering theory to be applied to our understanding of the normal and pathological mechanical behaviours of collagenous tissues under load. PMID:19897533

An integral theory of female urinary incontinence. Experimental and clinical considerations.

PubMed

Petros, P E; Ulmsten, U I

1990-01-01

In this Theory paper, the complex interplay of the specific structures involved in female urinary continence are analyzed. In addition the effects of age, hormones, and iatrogenically induced scar tissue on these structures, are discussed specifically with regard to understanding the proper basis for treatment of urinary incontinence. According to the Theory stress and urge symptoms may both derive, for different reasons from the same anatomical defect, a lax vagina. This laxity may be caused by defects within the vaginal wall itself, or its supporting structures i.e. ligaments, muscles, and their connective tissue insertions. The vagina has a dual function. It mediates (transmits) the various muscle movements involved in bladder neck opening and closure through three separate closure mechanisms. It also has a structural function, and prevents urgency by supporting the hypothesized stretch receptors at the proximal urethra and bladder neck. Altered collagen/elastin in the vaginal connective tissue and/or its ligamentous supports may cause laxity. This dissipates the muscle contraction, causing stress incontinence, and/or activation of an inappropriate micturition reflex, ("bladder instability") by stimulation of bladder base stretch receptors. The latter is manifested by symptoms of frequency, urgency, nocturia with or without urine loss.

Enigmatic insight into collagen

PubMed Central

Deshmukh, Shrutal Narendra; Dive, Alka M; Moharil, Rohit; Munde, Prashant

2016-01-01

Collagen is a unique, triple helical molecule which forms the major part of extracellular matrix. It is the most abundant protein in the human body, representing 30% of its dry weight. It is the fibrous structural protein that makes up the white fibers (collagen fibers) of skin, tendons, bones, cartilage and all other connective tissues. Collagens are not only essential for the mechanical resistance and resilience of multicellular organisms, but are also signaling molecules defining cellular shape and behavior. The human body has at least 16 types of collagen, but the most prominent types are I, II and III. Collagens are produced by several cell types and are distinguishable by their molecular compositions, morphologic characteristics, distribution, functions and pathogenesis. This is the major fibrous glycoprotein present in the extracellular matrix and in connective tissue and helps in maintaining the structural integrity of these tissues. It has a triple helical structure. Various studies have proved that mutations that modify folding of the triple helix result in identifiable genetic disorders. Collagen diseases share certain similarities with autoimmune diseases, because autoantibodies specific to each collagen disease are produced. Therefore, this review highlights the role of collagen in normal health and also the disorders associated with structural and functional defects in collagen. PMID:27601823

Unusual glycosaminoglycans from a deep sea hydrothermal bacterium improve fibrillar collagen structuring and fibroblast activities in engineered connective tissues.

PubMed

Senni, Karim; Gueniche, Farida; Changotade, Sylvie; Septier, Dominique; Sinquin, Corinne; Ratiskol, Jacqueline; Lutomski, Didier; Godeau, Gaston; Guezennec, Jean; Colliec-Jouault, Sylvia

2013-04-23

Biopolymers produced by marine organisms can offer useful tools for regenerative medicine. Particularly, HE800 exopolysaccharide (HE800 EPS) secreted by a deep-sea hydrothermal bacterium displays an interesting glycosaminoglycan-like feature resembling hyaluronan. Previous studies demonstrated its effectiveness to enhance in vivo bone regeneration and to support osteoblastic cell metabolism in culture. Thus, in order to assess the usefulness of this high-molecular weight polymer in tissue engineering and tissue repair, in vitro reconstructed connective tissues containing HE800 EPS were performed. We showed that this polysaccharide promotes both collagen structuring and extracellular matrix settle by dermal fibroblasts. Furthermore, from the native HE800 EPS, a low-molecular weight sulfated derivative (HE800 DROS) displaying chemical analogy with heparan-sulfate, was designed. Thus, it was demonstrated that HE800 DROS mimics some properties of heparan-sulfate, such as promotion of fibroblast proliferation and inhibition of matrix metalloproteinase (MMP) secretion. Therefore, we suggest that the HE800EPS family can be considered as an innovative biotechnological source of glycosaminoglycan-like compounds useful to design biomaterials and drugs for tissue engineering and repair.

Unusual Glycosaminoglycans from a Deep Sea Hydrothermal Bacterium Improve Fibrillar Collagen Structuring and Fibroblast Activities in Engineered Connective Tissues

PubMed Central

Senni, Karim; Gueniche, Farida; Changotade, Sylvie; Septier, Dominique; Sinquin, Corinne; Ratiskol, Jacqueline; Lutomski, Didier; Godeau, Gaston; Guezennec, Jean; Colliec-Jouault, Sylvia

2013-01-01

Biopolymers produced by marine organisms can offer useful tools for regenerative medicine. Particularly, HE800 exopolysaccharide (HE800 EPS) secreted by a deep-sea hydrothermal bacterium displays an interesting glycosaminoglycan-like feature resembling hyaluronan. Previous studies demonstrated its effectiveness to enhance in vivo bone regeneration and to support osteoblastic cell metabolism in culture. Thus, in order to assess the usefulness of this high-molecular weight polymer in tissue engineering and tissue repair, in vitro reconstructed connective tissues containing HE800 EPS were performed. We showed that this polysaccharide promotes both collagen structuring and extracellular matrix settle by dermal fibroblasts. Furthermore, from the native HE800 EPS, a low-molecular weight sulfated derivative (HE800 DROS) displaying chemical analogy with heparan-sulfate, was designed. Thus, it was demonstrated that HE800 DROS mimics some properties of heparan-sulfate, such as promotion of fibroblast proliferation and inhibition of matrix metalloproteinase (MMP) secretion. Therefore, we suggest that the HE800EPS family can be considered as an innovative biotechnological source of glycosaminoglycan-like compounds useful to design biomaterials and drugs for tissue engineering and repair. PMID:23612369

Disruptions of brain structural network in end-stage renal disease patients with long-term hemodialysis and normal-appearing brain tissues.

PubMed

Chou, Ming-Chung; Ko, Chih-Hung; Chang, Jer-Ming; Hsieh, Tsyh-Jyi

2018-05-04

End-stage renal disease (ESRD) patients on hemodialysis were demonstrated to exhibit silent and invisible white-matter alterations which would likely lead to disruptions of brain structural networks. Therefore, the purpose of this study was to investigate the disruptions of brain structural network in ESRD patients. Thiry-three ESRD patients with normal-appearing brain tissues and 29 age- and gender-matched healthy controls were enrolled in this study and underwent both cognitive ability screening instrument (CASI) assessment and diffusion tensor imaging (DTI) acquisition. Brain structural connectivity network was constructed using probabilistic tractography with automatic anatomical labeling template. Graph-theory analysis was performed to detect the alterations of node-strength, node-degree, node-local efficiency, and node-clustering coefficient in ESRD patients. Correlational analysis was performed to understand the relationship between network measures, CASI score, and dialysis duration. Structural connectivity, node-strength, node-degree, and node-local efficiency were significantly decreased, whereas node-clustering coefficient was significantly increased in ESRD patients as compared with healthy controls. The disrupted local structural networks were generally associated with common neurological complications of ESRD patients, but the correlational analysis did not reveal significant correlation between network measures, CASI score, and dialysis duration. Graph-theory analysis was helpful to investigate disruptions of brain structural network in ESRD patients with normal-appearing brain tissues. Copyright © 2018. Published by Elsevier Masson SAS.

Optical Histology: High-Resolution Visualization of Tissue Microvasculature

NASA Astrophysics Data System (ADS)

Moy, Austin Jing-Ming

Mammalian tissue requires the delivery of nutrients, growth factors, and the exchange of oxygen and carbon dioxide gases to maintain normal function. These elements are delivered by the blood, which travels through the connected network of blood vessels, known as the vascular system. The vascular system consists of large feeder blood vessels (arteries and veins) that are connected to the small blood vessels (arterioles and venules), which in turn are connected to the capillaries that are directly connected to the tissue and facilitate gas exchange and nutrient delivery. These small blood vessels and capillaries make up an intricate but organized network of blood vessels that exist in all mammalian tissues known as the microvasculature and are very important in maintaining the health and proper function of mammalian tissue. Due to the importance of the microvasculature in tissue survival, disruption of the microvasculature typically leads to tissue dysfunction and tissue death. The most prevalent method to study the microvasculature is visualization. Immunohistochemistry (IHC) is the gold-standard method to visualize tissue microvasculature. IHC is very well-suited for highly detailed interrogation of the tissue microvasculature at the cellular level but is unwieldy and impractical for wide-field visualization of the tissue microvasculature. The objective my dissertation research was to develop a method to enable wide-field visualization of the microvasculature, while still retaining the high-resolution afforded by optical microscopy. My efforts led to the development of a technique dubbed "optical histology" that combines chemical and optical methods to enable high-resolution visualization of the microvasculature. The development of the technique first involved preliminary studies to quantify optical property changes in optically cleared tissues, followed by development and demonstration of the methodology. Using optical histology, I successfully obtained high resolution, depth sectioned images of the microvasculature in mouse brain and the coronary microvasculature in mouse heart. Future directions of optical histology include the potential to facilitate visualization of the entire microvascular structure of an organ as well as visualization of other tissue molecular markers of interest.

Rigid spine reinforced polymer microelectrode array probe and method of fabrication

DOEpatents

Tabada, Phillipe; Pannu, Satinderpall S

2014-05-27

A rigid spine-reinforced microelectrode array probe and fabrication method. The probe includes a flexible elongated probe body with conductive lines enclosed within a polymeric material. The conductive lines connect microelectrodes found near an insertion end of the probe to respective leads at a connector end of the probe. The probe also includes a rigid spine, such as made from titanium, fixedly attached to the probe body to structurally reinforce the probe body and enable the typically flexible probe body to penetrate and be inserted into tissue, such as neural tissue. By attaching or otherwise fabricating the rigid spine to connect to only an insertion section of the probe body, an integrally connected cable section of the probe body may remain flexible.

Cytoskeletal remodeling of connective tissue fibroblasts in response to static stretch is dependent on matrix material properties

PubMed Central

Abbott, Rosalyn D; Koptiuch, Cathryn; Iatridis, James C; Howe, Alan K; Badger, Gary J; Langevin, Helene M

2012-01-01

In areolar “loose” connective tissue, fibroblasts remodel their cytoskeleton within minutes in response to static stretch resulting in increased cell body cross-sectional area that relaxes the tissue to a lower state of resting tension. It remains unknown whether the loosely arranged collagen matrix, characteristic of areolar connective tissue, is required for this cytoskeletal response to occur. The purpose of this study was to evaluate cytoskeletal remodeling of fibroblasts in and dissociated from areolar and dense connective tissue in response to 2 hours of static stretch in both native tissue and collagen gels of varying crosslinking. Rheometric testing indicated that the areolar connective tissue had a lower dynamic modulus and was more viscous than the dense connective tissue. In response to stretch, cells within the more compliant areolar connective tissue adopted a large “sheet-like” morphology that was in contrast to the smaller dendritic morphology in the dense connective tissue. By adjusting the in vitro collagen crosslinking, and the resulting dynamic modulus, it was demonstrated that cells dissociated from dense connective tissue are capable of responding when seeded into a compliant matrix, while cells dissociated from areolar connective tissue can lose their ability to respond when their matrix becomes stiffer. This set of experiments indicated stretch-induced fibroblast expansion was dependent on the distinct matrix material properties of areolar connective tissues as opposed to the cells’ tissue of origin. These results also suggest that disease and pathological processes with increased crosslinks, such as diabetes and fibrosis, could impair fibroblast responsiveness in connective tissues. PMID:22552950

Mixed Connective Tissue Disease

MedlinePlus

Mixed connective tissue disease Overview Mixed connective tissue disease has signs and symptoms of a combination of disorders — primarily lupus, scleroderma and polymyositis. For this reason, mixed connective tissue disease ...

Spatial Statistics for Segmenting Histological Structures in H&E Stained Tissue Images.

PubMed

Nguyen, Luong; Tosun, Akif Burak; Fine, Jeffrey L; Lee, Adrian V; Taylor, D Lansing; Chennubhotla, S Chakra

2017-07-01

Segmenting a broad class of histological structures in transmitted light and/or fluorescence-based images is a prerequisite for determining the pathological basis of cancer, elucidating spatial interactions between histological structures in tumor microenvironments (e.g., tumor infiltrating lymphocytes), facilitating precision medicine studies with deep molecular profiling, and providing an exploratory tool for pathologists. This paper focuses on segmenting histological structures in hematoxylin- and eosin-stained images of breast tissues, e.g., invasive carcinoma, carcinoma in situ, atypical and normal ducts, adipose tissue, and lymphocytes. We propose two graph-theoretic segmentation methods based on local spatial color and nuclei neighborhood statistics. For benchmarking, we curated a data set of 232 high-power field breast tissue images together with expertly annotated ground truth. To accurately model the preference for histological structures (ducts, vessels, tumor nets, adipose, etc.) over the remaining connective tissue and non-tissue areas in ground truth annotations, we propose a new region-based score for evaluating segmentation algorithms. We demonstrate the improvement of our proposed methods over the state-of-the-art algorithms in both region- and boundary-based performance measures.

Specialized probes based on hydroxyapatite calcium for heart tissues research by atomic force microscopy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhukov, Mikhail, E-mail: cloudjyk@yandex.ru; Golubok, Alexander; Institute for Analytical Instrumentation, Russian Academy of Sciences

The new specialized AFM-probes with hydroxyapatite structures for atomic force microscopy of heart tissues calcification were created and studied. A process of probe fabrication is demonstrated. The adhesive forces between specialized hydroxyapatite probe and endothelium/subendothelial layers were investigated. It was found that the adhesion forces are significantly higher for the subendothelial layers. We consider that it is connected with the formation and localization of hydroxyapatite in the area of subendothelial layers of heart tissues. In addition, the roughness analysis and structure visualization of the endothelial surface of the heart tissue were carried out. The results show high efficiency of createdmore » specialized probes at study a calcinations process of the aortic heart tissues.« less

[The connective tissues, from the origin of the concept to its "Maturation" to extracellular matrix. Application to ocular tissues. Contribution to the history of medical sciences].

PubMed

Labat-Robert, J; Robert, L; Pouliquen, Y

2011-06-01

The "Tissue" concept emerged apparently in the medical literature at about the French revolution, during the second half of the 18(th) century. It was found in the texts written by the physicians of Béarn and Montpellier, the Bordeu-s and also by the famous physician, Felix Vicq d'Azyr, the last attending physician of the queen Marie-Antoinette, "Bordeu et al. (1775) et Pouliquen (2009)". It was elaborated into a coherent doctrine somewhat later by Xavier Bichat, considered as the founder of modern pathological anatomy, Bichat. With the advent of histochemistry, from the beginning of the 20(th) century, several of the principal macromolecular components of connective tissues, collagens, elastin, "acid mucopolysaccharides" (later glycosaminoglycans and proteoglycans) and finally structural glycoproteins were characterized. These constituents of connective tissues were then designated as components of the extracellular matrix (ECM), closely associated to the cellular components of these tissues by adhesive (structural) glycoproteins as fibronectin, several others and cell receptors, "recognising" ECM-components as integrins, the elastin-receptor and others. This molecular arrangement fastens cells to the ECM-components they synthesize and mediates the exchange of informations between the cells to the ECM (inside-out) and also from the ECM-components to the cells (outside-in). This macromolecular arrangement is specific for each tissue as a result of the differentiation of their cellular components. It is also the basis and condition of the fulfillment of the specific functions of differentiated tissues. This is a short description of the passage of the "tissue" concept from its vague origin towards its precise identification at the cellular and molecular level up to the recognition of its functional importance and its establishment as an autonomous science. This can be considered as a new example of the importance of metaphors for the progress of science, Keller (1995). Copyright © 2011 Elsevier Masson SAS. All rights reserved.

Imaging deep skeletal muscle structure using a high-sensitivity ultrathin side-viewing optical coherence tomography needle probe

PubMed Central

Yang, Xiaojie; Lorenser, Dirk; McLaughlin, Robert A.; Kirk, Rodney W.; Edmond, Matthew; Simpson, M. Cather; Grounds, Miranda D.; Sampson, David D.

2013-01-01

We have developed an extremely miniaturized optical coherence tomography (OCT) needle probe (outer diameter 310 µm) with high sensitivity (108 dB) to enable minimally invasive imaging of cellular structure deep within skeletal muscle. Three-dimensional volumetric images were acquired from ex vivo mouse tissue, examining both healthy and pathological dystrophic muscle. Individual myofibers were visualized as striations in the images. Degradation of cellular structure in necrotic regions was seen as a loss of these striations. Tendon and connective tissue were also visualized. The observed structures were validated against co-registered hematoxylin and eosin (H&E) histology sections. These images of internal cellular structure of skeletal muscle acquired with an OCT needle probe demonstrate the potential of this technique to visualize structure at the microscopic level deep in biological tissue in situ. PMID:24466482

Development of diagnostic and treatment strategies for glaucoma through understanding and modification of scleral and lamina cribrosa connective tissue

PubMed Central

Quigley, Harry A.; Cone, Frances E.

2013-01-01

There is considerable evidence that the state of ocular connective tissues and their response in glaucomatous disease affects the degree of glaucoma damage. Both experimental and clinical data suggest that improved diagnostic and prognostic information could be derived from assessment of the mechanical responsiveness of the sclera and lamina cribrosa to intraocular pressure (IOP). Controlled mutagenesis of the sclera has produced a mouse strain that is relatively resistant to increased IOP. Alteration of the baseline scleral state could be accomplished through either increased cross-linking of fibrillar components or their reduction. The sclera is a dynamic structure, altering its structure and behavior in response to IOP change. The biochemical pathways that control these responses are fertile areas for new glaucoma treatments. PMID:23535950

Pattern Genes Suggest Functional Connectivity of Organs

NASA Astrophysics Data System (ADS)

Qin, Yangmei; Pan, Jianbo; Cai, Meichun; Yao, Lixia; Ji, Zhiliang

2016-05-01

Human organ, as the basic structural and functional unit in human body, is made of a large community of different cell types that organically bound together. Each organ usually exerts highly specified physiological function; while several related organs work smartly together to perform complicated body functions. In this study, we present a computational effort to understand the roles of genes in building functional connection between organs. More specifically, we mined multiple transcriptome datasets sampled from 36 human organs and tissues, and quantitatively identified 3,149 genes whose expressions showed consensus modularly patterns: specific to one organ/tissue, selectively expressed in several functionally related tissues and ubiquitously expressed. These pattern genes imply intrinsic connections between organs. According to the expression abundance of the 766 selective genes, we consistently cluster the 36 human organs/tissues into seven functional groups: adipose & gland, brain, muscle, immune, metabolism, mucoid and nerve conduction. The organs and tissues in each group either work together to form organ systems or coordinate to perform particular body functions. The particular roles of specific genes and selective genes suggest that they could not only be used to mechanistically explore organ functions, but also be designed for selective biomarkers and therapeutic targets.

Mechano-sensing and mechano-reaction of soft connective tissue cells

NASA Astrophysics Data System (ADS)

Lambert, Ch. A.; Nusgens, B. V.; Lapière, Ch. M.

One main function of the connective tissues is to provide cells with a mechanically resistant attachment support required for survival, division and differentiation. All cells contain membrane-anchored attachment proteins able to recognize specific chemical motifs in the extracellular macromolecules forming the supporting scaffold, made of various types of collagen, adhesive glycoproteins, elastin, proteoglycans, etc... These cell-matrix interactions are mainly mediated by re ceptors of the integrins family, heterodimeric molecules made of an extracellular domain connected through a transmembrane sequence to an intracytoplasmic tail. Upon recognition of the extracellular ligand, the clustering and activation of the integrins result in the recruitment of a complex of proteins and formation of the focal adhesion plaque, containing both cytoskeletal and catalytic signaling molecules. Activation results in polymerization of actin and formation of stress fibers. These structures establish a physical link between the extracellular matrix components and the cytoskeleton through the integrins providing a continuous path acting as a mechanotransducer. This connection is used by the cells to perform their mechanical functions as adhesion, migration and traction. In vitro experimental models using fibroblasts in a collagen gel demonstrate that cells are in mechanical equilibrium with their support which regulates their replicative and biosynthetic phenotype. The present review discusses the molecular structures operating in the transmission of the mechanical messages from the support to the connective tissue cells, and their effect on the cellular machinery. We present arguments for investigating these mechanisms in understanding the perception of reduced gravity and the resulting reaction leading to microgravity induced pathologies.

Preliminary embryological study of the radiological concept of retroperitoneal interfascial planes: what are the interfascial planes?

PubMed

Ishikawa, Kazuo; Nakao, Shota; Murakami, Gen; Rodríguez-Vázquez, Jose Francisco; Matsuoka, Tetsuya; Nakamuro, Makoto; Shimazu, Takeshi

2014-12-01

Recently, the radiological concept of retroperitoneal interfascial planes has been widely accepted to explain the extension of retroperitoneal pathologies. This study aimed to explore embryologically based corroborative evidence, which remains to be elucidated, for this concept. Using serial or semi-serial transverse sections from 29 human fetuses at the 5th-25th week of fetal age, we microscopically observed the development of the retroperitoneal fasciae and other structures in the retroperitoneal connective tissue. A hypothesis for the formation of the interfascial planes was generated from the developmental study and analysis of retroperitoneal fasciae in computed tomography images from 224 patients. Whereas the loose connective tissue was uniformly distributed in the retroperitoneum by the 9th week, the primitive renal and transversalis fasciae appeared at the 10th-12th week, as previous research has noted. By the 23rd week, the renal fascia, transversalis fascia, and primitive adipose tissue of the flank pad emerged. In addition, the primitive lateroconal fascia, which runs parallel to and close to the posterior renal fascia, emerged between the renal fascia and the adipose tissue of the flank pad. Conversely, pre-existing loose connective tissue was sandwiched between the opposing fasciae and was compressed and narrowed by the developing organs and fatty tissues. Through this developmental study, we provided the hypothesis that the compressed loose connective tissue and both opposed fasciae compose the interfascial planes. Analysis of the thickened retroperitoneal fasciae in computed tomography images supported this hypothesis. Further developmental or histological studies are required to verify our hypothesis.

Diffusion MRI at 25: Exploring brain tissue structure and function

PubMed Central

Bihan, Denis Le; Johansen-Berg, Heidi

2013-01-01

Diffusion MRI (or dMRI) came into existence in the mid-1980s. During the last 25 years, diffusion MRI has been extraordinarily successful (with more than 300,000 entries on Google Scholar for diffusion MRI). Its main clinical domain of application has been neurological disorders, especially for the management of patients with acute stroke. It is also rapidly becoming a standard for white matter disorders, as diffusion tensor imaging (DTI) can reveal abnormalities in white matter fiber structure and provide outstanding maps of brain connectivity. The ability to visualize anatomical connections between different parts of the brain, non-invasively and on an individual basis, has emerged as a major breakthrough for neurosciences. The driving force of dMRI is to monitor microscopic, natural displacements of water molecules that occur in brain tissues as part of the physical diffusion process. Water molecules are thus used as a probe that can reveal microscopic details about tissue architecture, either normal or in a diseased state. PMID:22120012

Muscular force transmission: a unified, dual or multiple system? A review and some explorative experimental results.

PubMed

Huijing, P

1999-10-01

Structures contributing to force transmission in muscle are reviewed combining some historical and relatively recently published experimental data. Also, effects of aponeurotomy and tenotomy are reviewed shortly as well as some new experimental results regarding these interventions that reinforce the concept of myofascial force transmission. The review is also illustrated by some new images of single muscle fibres from Xenopus Laevis indicative of such transmission and some data about locations of insertion of human gluteus maximus muscle. From this review and the new material, emerges a line of thought indicating that mechanical connections between muscle fibres and intramuscular connective tissue play an important role in force transmission. New experimental observations are presented for non-spanning muscle (i.c., rat biceps femoris muscle), regarding the great variety of types of intramuscular connections that exist i n addition to myo-tendinous junctions at the perimuscular ends of muscle fibres. Such connections are classified as (1) tapered end connections, (2) Myo-myonal junctions, (3) myo-epimysial junctions and (3) Myo-endomysial junctions. This line of thought is followed up by consideration of a possible role of connections of intra- and extramuscular connective tissue in force transmission out of the muscle. Experimental results of an explorative nature, regarding the interactions of extensor digitorum longus (EDL), tibialis anterior (TA) and hallucis longus (HAL) muscles within a relatively intact dorsal flexor compartment of the rat hind leg, indicate that: (1) length force properties of EDL are influenced by TA activity in a length dependent fashion. Depending on TA length, force exerted by EDL, kept at constant origin insertion distance, is variable and the effect is influenced by EDL length itself as well; (2) Force is transmitted from muscle to extramuscular connective tissue and vice versa. As a consequence force exerted at proximal and distal tendons of a muscle are not always equal. The difference being transmitted by extramuscular connective tissue and may appear at the tendons of other muscles or may be transmitted via connective tissue directly to bone. It is concluded that the system of force transmission from skeletal muscle should be considered as a multiple system.

Undifferentiated Connective Tissue Disease

MedlinePlus

... Home Conditions Undifferentiated Connective Tissue Disease (UCTD) Undifferentiated Connective Tissue Disease (UCTD) Make an Appointment Find a Doctor ... by Barbara Goldstein, MD (February 01, 2016) Undifferentiated connective tissue disease (UCTD) is a systemic autoimmune disease. This ...

Nanomechanical signatures of oral submucous fibrosis in sub-epithelial connective tissue.

PubMed

Anura, Anji; Das, Debanjan; Pal, Mousumi; Paul, Ranjan Rashmi; Das, Soumen; Chatterjee, Jyotirmoy

2017-01-01

Oral sub-mucous fibrosis (OSF), a potentially malignant disorder, exhibits extensive remodeling of extra-cellular matrix in the form of sub-epithelial fibrosis which is a possible sequel of assaults from different oral habit related irritants. It has been assumed that micro/nanobio-mechanical imbalance experienced in the oral mucosa due to fibrosis may be deterministic for malignant potential (7-13%) of this pathosis. Present study explores changes in mechanobiological attributes of sub-epithelial connective tissue of OSF and the normal counterpart. The atomic force microscopy was employed to investigate tissue topography at micro/nano levels. It documented the presence of closely packed parallel arrangement of dense collagen fibers with wide variation in bandwidth and loss of D-space in OSF as compared to normal. The AFM based indentation revealed that sub-epithelium of OSF tissue has lost its flexibility with increased Young's modulus, stiffness, adhesiveness and reduced deformation of the juxta-epithealial connective tissue towards the deeper layer. These significant variations in nano-mechanical properties of the connective tissue indicated plausible impacts on patho-physiological microenvironment. Excessive deposition of collagen I and diminished expression of collagen III, fibronectin along with presence of α-SMA positive myofibroblast in OSF depicted its pathological basis and indicated the influence of altered ECM on this pathosis. The mechanobiological changes in OSF were corroborative with change in collagen composition recorded through immunohistochemistry and RT-PCR. The revelation of comparative nanomechanical profiles of normal oral mucosa and OSF in the backdrop of their structural and cardinal molecular attributes thus became pivotal for developing holistic pathobiological insight about possible connects for malignant transformation of this pre-cancer. Copyright © 2016 Elsevier Ltd. All rights reserved.

Fibrous tissues growth and remodeling: Evolutionary micro-mechanical theory

NASA Astrophysics Data System (ADS)

Lanir, Yoram

2017-10-01

Living fibrous tissues are composite materials having the unique ability to adapt their size, shape, structure and mechanical properties in response to external loading. This adaptation, termed growth and remodeling (G&R), occurs throughout life and is achieved via cell-induced turnover of tissue constituents where some are degraded and new ones are produced. Realistic mathematical modeling of G&R provides insight into the basic processes, allows for hypotheses testing, and constitutes an essential tool for establishing clinical thresholds of pathological remodeling and for the production of tissue substitutes aimed to achieve target structure and properties. In this study, a general 3D micro-mechanical multi-scale theory of G&R in fibrous tissue was developed which connects between the evolution of the tissue structure and properties, and the underlying mechano-biological turnover events of its constituents. This structural approach circumvents a fundamental obstacle in modeling growth mechanics since the growth motion is not bijective. The model was realized for a flat tissue under two biaxial external loadings using data-based parameter values. The predictions show close similarity to characteristics of remodeled adult tissue including its structure, anisotropic and non-linear mechanical properties, and the onset of in situ pre-strain and pre-stress. The results suggest that these important features of living fibrous tissues evolve as they grow.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harper, J.; Amiel, D.; Harper, E.

The authors examined the patellar tendon (PT), anterior cruciate ligament (ACL) and medial collateral ligament (MCL) from normal rabbits for collagenase activity. All three connective tissues contain large amounts of collagen and the catabolism of this structural protein is important to their integrity. The authors cultured each tissue in serum free medium for 14 days. Collagenase was produced by all three connective tissues after a lag period of up to 7 days, as detected by the /sup 14/C-glycine peptide-release assay. Culture media that did not express enzyme the authors found to contain inhibitory activity. The collagenases and inhibitors from eachmore » tissue have been quantitated and characterized. After 9 days the collagenase activity for the rabbit periarticular tissues was 6.1 (PT), 4.4 (MCL) and 8.6 (ACL) units per milligram of secreted protein. The cleavage site of all three collagenases was found to be similar to that observed for rabbit skin collagenase, and generation of reaction products TC/sup A/ and TC/sup B/ was demonstrated by collagenases from PT, MCL and ACL. These results suggest that the metabolism of ligaments and tendon is regulated by the production of zymogen, active collagenase and inhibitor, similar to other connective tissues. The role of these components in joint injury and joint diseases is currently being investigated.« less

The decrease in silicon concentration of the connective tissues with age in rats is a marker of connective tissue turnover.

PubMed

Jugdaohsingh, Ravin; Watson, Abigail I E; Pedro, Liliana D; Powell, Jonathan J

2015-06-01

Silicon may be important for bone and connective tissue health. Higher concentrations of silicon are suggested to be associated with bone and the connective tissues, compared with the non-connective soft tissues. Moreover, in connective tissues it has been suggested that silicon levels may decrease with age based upon analyses of human aorta. These claims, however, have not been tested under controlled conditions. Here connective and non-connective tissues were collected and analysed for silicon levels from female Sprague-Dawley rats of different ages (namely, 3, 5, 8, 12, 26 and 43 weeks; n=8-10 per age group), all maintained on the same feed source and drinking water, and kept in the same environment from weaning to adulthood. Tissues (696 samples) were digested in nitric acid and analysed by inductively coupled plasma optical emission spectrometry for total silicon content. Fasting serum samples were also collected, diluted and analysed for silicon. Higher concentrations of silicon (up to 50-fold) were found associated with bone and the connective tissues compared with the non-connective tissues. Although total silicon content increased with age in all tissues, the highest connective tissue silicon concentrations (up to 9.98 μg/g wet weight) were found in young weanling rats, decreasing thereafter with age (by 2-6 fold). Fasting serum silicon concentrations reflected the pattern of connective tissue silicon concentrations and, both measures, when compared to collagen data from a prior experiment in Sprague-Dawley rats, mirrored type I collagen turnover with age. Our findings confirm the link between silicon and connective tissues and would imply that young growing rats have proportionally higher requirements for dietary silicon than mature adults, for bone and connective tissue development, although this was not formally investigated here. However, estimation of total body silicon content suggested that actual Si requirements may be substantially lower than previously estimated which could explain why absolute silicon deficiency is difficult to achieve but, when it is achieved in young growing animals, it results in stunted growth and abnormal development of bone and other connective tissues. Copyright © 2015. Published by Elsevier Inc.

The decrease in silicon concentration of the connective tissues with age in rats is a marker of connective tissue turnover☆

PubMed Central

Jugdaohsingh, Ravin; Watson, Abigail I.E.; Pedro, Liliana D.; Powell, Jonathan J.

2015-01-01

Silicon may be important for bone and connective tissue health. Higher concentrations of silicon are suggested to be associated with bone and the connective tissues, compared with the non-connective soft tissues. Moreover, in connective tissues it has been suggested that silicon levels may decrease with age based upon analyses of human aorta. These claims, however, have not been tested under controlled conditions. Here connective and non-connective tissues were collected and analysed for silicon levels from female Sprague–Dawley rats of different ages (namely, 3, 5, 8, 12, 26 and 43 weeks; n = 8–10 per age group), all maintained on the same feed source and drinking water, and kept in the same environment from weaning to adulthood. Tissues (696 samples) were digested in nitric acid and analysed by inductively coupled plasma optical emission spectrometry for total silicon content. Fasting serum samples were also collected, diluted and analysed for silicon. Higher concentrations of silicon (up to 50-fold) were found associated with bone and the connective tissues compared with the non-connective tissues. Although total silicon content increased with age in all tissues, the highest connective tissue silicon concentrations (up to 9.98 μg/g wet weight) were found in young weanling rats, decreasing thereafter with age (by 2–6 fold). Fasting serum silicon concentrations reflected the pattern of connective tissue silicon concentrations and, both measures, when compared to collagen data from a prior experiment in Sprague–Dawley rats, mirrored type I collagen turnover with age. Our findings confirm the link between silicon and connective tissues and would imply that young growing rats have proportionally higher requirements for dietary silicon than mature adults, for bone and connective tissue development, although this was not formally investigated here. However, estimation of total body silicon content suggested that actual Si requirements may be substantially lower than previously estimated which could explain why absolute silicon deficiency is difficult to achieve but, when it is achieved in young growing animals, it results in stunted growth and abnormal development of bone and other connective tissues. PMID:25687224

Viscoelastic properties of bovine orbital connective tissue and fat: constitutive models

PubMed Central

Yoo, Lawrence; Gupta, Vijay; Lee, Choongyeop; Kavehpore, Pirouz

2012-01-01

Reported mechanical properties of orbital connective tissue and fat have been too sparse to model strain–stress relationships underlying biomechanical interactions in strabismus. We performed rheological tests to develop a multi-mode upper convected Maxwell (UCM) model of these tissues under shear loading. From 20 fresh bovine orbits, 30 samples of connective tissue were taken from rectus pulley regions and 30 samples of fatty tissues from the posterior orbit. Additional samples were defatted to determine connective tissue weight proportion, which was verified histologically. Mechanical testing in shear employed a triborheometer to perform: strain sweeps at 0.5–2.0 Hz; shear stress relaxation with 1% strain; viscometry at 0.01–0.5 s−1 strain rate; and shear oscillation at 1% strain. Average connective tissue weight proportion was 98% for predominantly connective tissue and 76% for fatty tissue. Connective tissue specimens reached a long-term relaxation modulus of 668 Pa after 1,500 s, while corresponding values for fatty tissue specimens were 290 Pa and 1,100 s. Shear stress magnitude for connective tissue exceeded that of fatty tissue by five-fold. Based on these data, we developed a multimode UCM model with variable viscosities and time constants, and a damped hyperelastic response that accurately described measured properties of both connective and fatty tissues. Model parameters differed significantly between the two tissues. Viscoelastic properties of predominantly connective orbital tissues under shear loading differ markedly from properties of orbital fat, but both are accurately reflected using UCM models. These viscoelastic models will facilitate realistic global modeling of EOM behavior in binocular alignment and strabismus. PMID:21207094

Differential diagnosis and diagnostic flow chart of joint hypermobility syndrome/ehlers-danlos syndrome hypermobility type compared to other heritable connective tissue disorders.

PubMed

Colombi, Marina; Dordoni, Chiara; Chiarelli, Nicola; Ritelli, Marco

2015-03-01

Joint hypermobility syndrome/Ehlers-Danlos syndrome hypermobility type (JHS/EDS-HT) is an evolving and protean disorder mostly recognized by generalized joint hypermobility and without a defined molecular basis. JHS/EDS-HT also presents with other connective tissue features affecting a variety of structures and organs, such as skin, eye, bone, and internal organs. However, most of these signs are present in variable combinations and severity in many other heritable connective tissue disorders. Accordingly, JHS/EDS-HT is an "exclusion" diagnosis which needs the absence of any consistent feature indicative of other partially overlapping connective tissue disorders. While both Villefranche and Brighton criteria include such an exclusion as a mandatory item, a systematic approach for reaching a stringent clinical diagnosis of JHS/EDS-HT is still lacking. The absence of a consensus on the diagnostic approach to JHS/EDS-HT concerning its clinical boundaries with similar conditions contribute to limit our actual understanding of the pathologic and molecular bases of this disorder. In this review, we revise the differential diagnosis of JHS/EDS-HT with those heritable connective tissue disorders which show a significant overlap with the former and mostly include EDS classic, vascular and kyphoscoliotic types, osteogenesis imperfecta, Marfan syndrome, Loeys-Dietz syndrome, arterial tortuosity syndrome, and lateral meningocele syndrome. A diagnostic flow chart is also offered with the attempt to support the less experienced clinician in stringently recognizing JHS/EDS-HT and stimulate the debate in the scientific community for both management and research purposes. © 2015 Wiley Periodicals, Inc.

Radiotherapy in patients with connective tissue diseases.

PubMed

Giaj-Levra, Niccolò; Sciascia, Savino; Fiorentino, Alba; Fersino, Sergio; Mazzola, Rosario; Ricchetti, Francesco; Roccatello, Dario; Alongi, Filippo

2016-03-01

The decision to offer radiotherapy in patients with connective tissue diseases continues to be challenging. Radiotherapy might trigger the onset of connective tissue diseases by increasing the expression of self-antigens, diminishing regulatory T-cell activity, and activating effectors of innate immunity (dendritic cells) through Toll-like receptor-dependent mechanisms, all of which could potentially lead to breaks of immune tolerance. This potential risk has raised some debate among radiation oncologists about whether patients with connective tissue diseases can tolerate radiation as well as people without connective tissue diseases. Because the number of patients with cancer and connective tissue diseases needing radiotherapy will probably increase due to improvements in medical treatment and longer life expectancy, the issue of interactions between radiotherapy and connective tissue diseases needs to be clearer. In this Review, we discuss available data and evidence for patients with connective tissue diseases treated with radiotherapy. Copyright © 2016 Elsevier Ltd. All rights reserved.

Fascial reinforcement fixing the bronchi to the heart: its anatomy and clinical significance.

PubMed

Nakanishi, Kozo; Goto, Hidenori; Ito, Tomokazu

2017-12-01

The details of the mediastinal fascia have been scarcely described and the bronchopericardial membrane is the only known structure that is present between the bronchi and the pericardium. However, the anatomical description of this structure is unclear. This study aimed to investigate the fascial structures between the bronchi and the pericardium based on surgical findings. The connective tissues in the mid-mediastinum were observed surgically when lung lobectomy, including mediastinal lymph node dissection for lung cancer, was performed at our institute from April 2011 to March 2016. In total, 96 lobectomies were performed in 94 patients. A firm fibrous structure connecting the tracheobronchus and the fibrous pericardium was observed. It fixes the central bronchi to the pericardium and is composed of three parts. The largest part exists in front of the carina, its appearance is membranous, and runs behind the pulmonary artery. The other parts run over the right pulmonary artery and diverge at its superior trunk. The location at which all these structures fuse to the pericardium is the venous part of the hilum cordis (VHC). The results showed that connections of the dense fibrous tissues existed between the tracheobronchus and VHC. The structure not only works as a ligament that fixes the bronchi to the mid-mediastinum, but also divides the mid-mediastinum into two compartments: the Baréty and subcarinal spaces. The anatomy of the structure observed in this study differs from the previous description of the bronchopericardial membrane.

[Muscles and connective tissue: histology].

PubMed

Delage, J-P

2012-10-01

Here, we give some comments about the DVD movies "Muscle Attitudes" from Endovivo productions, the movies up lighting some loss in the attention given to studies on the connective tissue, and especially them into muscles. The main characteristics of the different components in the intra-muscular connective tissue (perimysium, endomysium, epimysium) are shown here with special references to their ordered architecture and special references to their spatial distributions. This connective tissue is abundant into the muscles and is in continuity with the muscles in vicinity, with their tendons and their sheath, sticking the whole on skin. This connective tissue has also very abundant connections on the muscles fibres. It is then assumed that the connective tissue sticks every organs or cells of the locomotion system. Considering the elastic properties of the collagen fibres which are the most abundant component of connective tissue, it is possible to up light a panel of connective tissue associated functions such as the transmission of muscle contractions or the regulation of protein and energetic muscles metabolism. Copyright © 2012. Published by Elsevier SAS.

Connective tissue activation. XXXII. Structural and biologic characteristics of mesenchymal cell-derived connective tissue activating peptide-V.

PubMed

Cabral, A R; Cole, L A; Walz, D A; Castor, C W

1987-12-01

Connective tissue activating peptide-V (CTAP-V) is a single-chain, mesenchymal cell-derived anionic protein with large and small molecular forms (Mr of 28,000 and 16,000, respectively), as defined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The proteins have similar specific activities with respect to stimulation of hyaluronic acid and DNA formation in human synovial fibroblast cultures. S-carboxymethylation or removal of sialic acid residues did not modify CTAP-V biologic activity. Rabbit antibodies raised separately against each of the purified CTAP-V proteins reacted, on immunodiffusion and on Western blot, with each antigen and neutralized mitogenic activity. The amino-terminal amino acid sequence of the CTAP-V proteins, determined by 2 laboratories, confirmed their structural similarities. The amino-terminal sequence through 37 residues was demonstrated for the smaller protein. The first 10 residues of CTAP-V (28 kd) were identical to the N-terminal decapeptide of CTAP-V (16 kd). The C-terminal sequence, determined by carboxypeptidase Y digestion, was the same for both CTAP-V molecular species. The 2 CTAP-V peptides had similar amino acid compositions, whether residues were expressed as a percent of the total or were normalized to mannose. Reduction of native CTAP-V protein released sulfhydryl groups in a protein:disulfide ratio of 1:2; this suggests that CTAP-V contains 2 intramolecular disulfide bonds. Clearly, CTAP-V is a glycoprotein. The carbohydrate content of CTAP-V (16 kd) and CTAP-V (28 kd) is 27% and 25%, respectively. CTAP-V may have significance in relation to autocrine mechanisms for growth regulation of connective tissue cells and other cell types.

Genetics Home Reference: Kuskokwim syndrome

MedlinePlus

... collagens, which provide structure and strength to connective tissues that support the body's bones, joints, and ... U, Cundy T, Pyott SM, Christiansen HE, Hegde MR, Bank RA, Pals G, Ankala A, Conneely K, Seaver ...

Structure and function of the digestive system of solen grandis dunker

NASA Astrophysics Data System (ADS)

Sheng, Xiuzhen; Zhan, Wenbin; Ren, Sulian

2003-10-01

Structure and function of the digestive system of a bivalve mollusc, Solen grandis, were studied using light microscopy and histochemical methods. The wall of digestive tube consists of four layers: the mucosal epithelium, connective tissue, muscular and fibrosa or serosa (only in the portion of rectum) from the inner to the outer. The ciliated columnar epithelial cells, dispersed by cup-shaped mucous cells, rest on a thin base membrane. There are abundant blood spaces in connective tissue layer. The digestive diverticula are composed of multi-branched duct and digestive tubules. The digestive tubules are lined with digestive and basophilic secretory cells, and surrounded by a layer of smooth muscle fibers and connective tissues. Activities of acid and alkaline phosphatases, esterase and lipase are detected in the digestive cells, and the epithelia of stomach and intestine, suggesting that these cells are capable of intracellular digesting of food materials and absorbing. Besides, acid phosphatase and esterase activities are present in the posterior portion of esophagus. Phagocytes are abundant in blood spaces and the lumens of stomach and intestine, containing brown granules derived from the engulfed food materials. The present work indicates that phagocytes play important roles in ingestion and digestion of food materials, which is supported as well by the activities of acid phosphatase, esterase and lipase detected in blood spaces.

Hindlimb unloading alters ligament healing

NASA Technical Reports Server (NTRS)

Provenzano, Paolo P.; Martinez, Daniel A.; Grindeland, Richard E.; Dwyer, Kelley W.; Turner, Joanne; Vailas, Arthur C.; Vanderby, Ray Jr

2003-01-01

We investigated the hypothesis that hindlimb unloading inhibits healing in fibrous connective tissue such as ligament. Male rats were assigned to 3- and 7-wk treatment groups with three subgroups each: sham control, ambulatory healing, and hindlimb-suspended healing. Ambulatory and suspended animals underwent surgical rupture of their medial collateral ligaments, whereas sham surgeries were performed on control animals. After 3 or 7 wk, mechanical and/or morphological properties were measured in ligament, muscle, and bone. During mechanical testing, most suspended ligaments failed in the scar region, indicating the greatest impairment was to ligament and not to bone-ligament insertion. Ligament testing revealed significant reductions in maximum force, ultimate stress, elastic modulus, and low-load properties in suspended animals. In addition, femoral mineral density, femoral strength, gastrocnemius mass, and tibialis anterior mass were significantly reduced. Microscopy revealed abnormal scar formation and cell distribution in suspended ligaments with extracellular matrix discontinuities and voids between misaligned, but well-formed, collagen fiber bundles. Hence, stress levels from ambulation appear unnecessary for formation of fiber bundles yet required for collagen to form structurally competent continuous fibers. Results support our hypothesis that hindlimb unloading impairs healing of fibrous connective tissue. In addition, this study provides compelling morphological evidence explaining the altered structure-function relationship in load-deprived healing connective tissue.

Scanning electron microscopy of echinoid podia.

PubMed

Florey, E; Cahill, M A

1982-01-01

Tube feet of the sea urchin Strongylocentrotus franciscanus were studied with the scanning electron microscope (SEM). By use of fractured preparations it was possible to obtain views of all components of the layered tube-foot wall. The outer epithelium was found to bear tufts of cilia possibly belonging to sensory cells. The nerve plexus was clearly revealed as being composed of bundles of varicose axons. The basal lamina, which covers the outer and inner surfaces of the connective tissue layer, was found to be a mechanically resistant and elastic membrane. The connective tissue appears as dense bundles of (collagen) fibers. The luminal epithelium (coelothelium) is a single layer of flagellated collar cells. There is no indication that the muscle fibers, which insert on the inner basal lamina of the connective tissue layer are innervated by axons from the basi-epithelial nerve plexus. The results agree with previous conclusions concerning tube-foot structure based on transmission electron microscopy, and provide additional information, particularly with regard to the outer and inner epithelia.

Cell migration through connective tissue in 3-D

NASA Astrophysics Data System (ADS)

Fabry, Ben

2008-03-01

A prerequisite for metastasis formation is the ability of tumor cells to invade and migrate through connective tissue. Four key components endow tumor cells with this ability: secretion of matrix-degrading enzymes, firm but temporary adhesion onto connective tissue fibers, contractile force generation, and rapid remodeling of cytoskeletal structures. Cell adhesion, contraction, and cytoskeletal remodeling are biomechanical parameter that can be measured on single cells using a panel of biophysical methods. We use 2-D and 3-D traction microscopy to measure contractile forces; magnetic tweezer microrheology to estimate adhesion strengths, cytoskeletal stiffness and molecular turn-over rates; and nanoscale particle tracking to measure cytoskeletal remodeling. On a wide range of tumor cell lines we could show that cell invasiveness correlates with increased expression of integrin adhesion receptors, increased contractile force generation, and increased speed of cytoskeletal reorganization. Each of those biomechanical parameters, however, varied considerably between cell lines of similar invasivity, suggesting that tumor cells employ multiple invasion strategies that cannot be unambiguously characterized using a single assay.

Viscoelastic properties of bovine orbital connective tissue and fat: constitutive models.

PubMed

Yoo, Lawrence; Gupta, Vijay; Lee, Choongyeop; Kavehpore, Pirouz; Demer, Joseph L

2011-12-01

Reported mechanical properties of orbital connective tissue and fat have been too sparse to model strain-stress relationships underlying biomechanical interactions in strabismus. We performed rheological tests to develop a multi-mode upper convected Maxwell (UCM) model of these tissues under shear loading. From 20 fresh bovine orbits, 30 samples of connective tissue were taken from rectus pulley regions and 30 samples of fatty tissues from the posterior orbit. Additional samples were defatted to determine connective tissue weight proportion, which was verified histologically. Mechanical testing in shear employed a triborheometer to perform: strain sweeps at 0.5-2.0 Hz; shear stress relaxation with 1% strain; viscometry at 0.01-0.5 s(-1) strain rate; and shear oscillation at 1% strain. Average connective tissue weight proportion was 98% for predominantly connective tissue and 76% for fatty tissue. Connective tissue specimens reached a long-term relaxation modulus of 668 Pa after 1,500 s, while corresponding values for fatty tissue specimens were 290 Pa and 1,100 s. Shear stress magnitude for connective tissue exceeded that of fatty tissue by five-fold. Based on these data, we developed a multi-mode UCM model with variable viscosities and time constants, and a damped hyperelastic response that accurately described measured properties of both connective and fatty tissues. Model parameters differed significantly between the two tissues. Viscoelastic properties of predominantly connective orbital tissues under shear loading differ markedly from properties of orbital fat, but both are accurately reflected using UCM models. These viscoelastic models will facilitate realistic global modeling of EOM behavior in binocular alignment and strabismus.

Absorption spectra of adenocarcinoma and squamous cell carcinoma cervical tissues

NASA Astrophysics Data System (ADS)

Ivashko, Pavlo; Peresunko, Olexander; Zelinska, Natalia; Alonova, Marina

2014-08-01

We studied a methods of assessment of a connective tissue of cervix in terms of specific volume of fibrous component and an optical density of staining of connective tissue fibers in the stroma of squamous cancer and cervix adenocarcinoma. An absorption spectra of blood plasma of the patients suffering from squamous cancer and cervix adenocarcinoma both before the surgery and in postsurgical periods were obtained. Linear dichroism measurements transmittance in polarized light at different orientations of the polarization plane relative to the direction of the dominant orientation in the structure of the sample of biotissues of stroma of squamous cancer and cervix adenocarcinoma were carried. Results of the investigation of the tumor tissues showed that the magnitude of the linear dichroism Δ is insignificant in the researched spectral range λ=280-840 nm and specific regularities in its change observed short-wave ranges.

Comparison of absorption spectra of adenocarcinoma and squamous cell carcinoma cervical tissue

NASA Astrophysics Data System (ADS)

Peresunko, O. P.; Zelinska, N. V.; Prydij, O. G.; Zymnyakov, D. A.; Ushakova, O. V.

2013-12-01

We studied a methods of assessment of a connective tissue of cervix in terms of specific volume of fibrous component and an optical density of staining of connective tissue fibers in the stroma of squamous cancer and cervix adenocarcinoma. An absorption spectra of blood plasma of the patients suffering from squamous cancer and cervix adenocarcinoma both before the surgery and in postsurgical periods were obtained. Linear dichroism measurements transmittance in polarized light at different orientations of the polarization plane relative to the direction of the dominant orientation in the structure of the sample of biotissues of stroma of squamous cancer and cervix adenocarcinoma were carried. Results of the investigation of the tumor tissues showed that the magnitude of the linear dichroism Δ is insignificant in the researched spectral range λ=280-840 nm and specific regularities in its change observed short-wave ranges.

Non-myogenic Contribution to Muscle Development and Homeostasis: The Role of Connective Tissues

PubMed Central

Nassari, Sonya; Duprez, Delphine; Fournier-Thibault, Claire

2017-01-01

Skeletal muscles belong to the musculoskeletal system, which is composed of bone, tendon, ligament and irregular connective tissue, and closely associated with motor nerves and blood vessels. The intrinsic molecular signals regulating myogenesis have been extensively investigated. However, muscle development, homeostasis and regeneration require interactions with surrounding tissues and the cellular and molecular aspects of this dialogue have not been completely elucidated. During development and adult life, myogenic cells are closely associated with the different types of connective tissue. Connective tissues are defined as specialized (bone and cartilage), dense regular (tendon and ligament) and dense irregular connective tissue. The role of connective tissue in muscle morphogenesis has been investigated, thanks to the identification of transcription factors that characterize the different types of connective tissues. Here, we review the development of the various connective tissues in the context of the musculoskeletal system and highlight their important role in delivering information necessary for correct muscle morphogenesis, from the early step of myoblast differentiation to the late stage of muscle maturation. Interactions between muscle and connective tissue are also critical in the adult during muscle regeneration, as impairment of the regenerative potential after injury or in neuromuscular diseases results in the progressive replacement of the muscle mass by fibrotic tissue. We conclude that bi-directional communication between muscle and connective tissue is critical for a correct assembly of the musculoskeletal system during development as well as to maintain its homeostasis in the adult. PMID:28386539

Non-myogenic Contribution to Muscle Development and Homeostasis: The Role of Connective Tissues.

PubMed

Nassari, Sonya; Duprez, Delphine; Fournier-Thibault, Claire

2017-01-01

Skeletal muscles belong to the musculoskeletal system, which is composed of bone, tendon, ligament and irregular connective tissue, and closely associated with motor nerves and blood vessels. The intrinsic molecular signals regulating myogenesis have been extensively investigated. However, muscle development, homeostasis and regeneration require interactions with surrounding tissues and the cellular and molecular aspects of this dialogue have not been completely elucidated. During development and adult life, myogenic cells are closely associated with the different types of connective tissue. Connective tissues are defined as specialized (bone and cartilage), dense regular (tendon and ligament) and dense irregular connective tissue. The role of connective tissue in muscle morphogenesis has been investigated, thanks to the identification of transcription factors that characterize the different types of connective tissues. Here, we review the development of the various connective tissues in the context of the musculoskeletal system and highlight their important role in delivering information necessary for correct muscle morphogenesis, from the early step of myoblast differentiation to the late stage of muscle maturation. Interactions between muscle and connective tissue are also critical in the adult during muscle regeneration, as impairment of the regenerative potential after injury or in neuromuscular diseases results in the progressive replacement of the muscle mass by fibrotic tissue. We conclude that bi-directional communication between muscle and connective tissue is critical for a correct assembly of the musculoskeletal system during development as well as to maintain its homeostasis in the adult.

Hyaluronic acid-based scaffolds for tissue engineering.

PubMed

Chircov, Cristina; Grumezescu, Alexandru Mihai; Bejenaru, Ludovic Everard

2018-01-01

Hyaluronic acid (HA) is a natural glycosaminoglycan found in the extracellular matrix of most connective tissues. Due to its chemical structure, HA is a hydrophilic polymer and it is characterized by a fast degradation rate. HA-based scaffolds for tissue engineering are intensively studied due to their increased biocompatibility, biodegradability and chemical modification. Depending on the processing technique, scaffolds can be prepared in the form of hydrogels, sponges, cryogels, and injectable hydrogels, all discussed in this review.

Automatic recognition of fundamental tissues on histology images of the human cardiovascular system.

PubMed

Mazo, Claudia; Trujillo, Maria; Alegre, Enrique; Salazar, Liliana

2016-10-01

Cardiovascular disease is the leading cause of death worldwide. Therefore, techniques for improving diagnosis and treatment in this field have become key areas for research. In particular, approaches for tissue image processing may support education system and medical practice. In this paper, an approach to automatic recognition and classification of fundamental tissues, using morphological information is presented. Taking a 40× or 10× histological image as input, three clusters are created with the k-means algorithm using a structural tensor and the red and the green channels. Loose connective tissue, light regions and cell nuclei are recognised on 40× images. Then, the cell nuclei's features - shape and spatial projection - and light regions are used to recognise and classify epithelial cells and tissue into flat, cubic and cylindrical. In a similar way, light regions, loose connective and muscle tissues are recognised on 10× images. Finally, the tissue's function and composition are used to refine muscle tissue recognition. Experimental validation is then carried out by histologist following expert criteria, along with manually annotated images that are used as a ground-truth. The results revealed that the proposed approach classified the fundamental tissues in a similar way to the conventional method employed by histologists. The proposed automatic recognition approach provides for epithelial tissues a sensitivity of 0.79 for cubic, 0.85 for cylindrical and 0.91 for flat. Furthermore, the experts gave our method an average score of 4.85 out of 5 in the recognition of loose connective tissue and 4.82 out of 5 for muscle tissue recognition. Copyright © 2016 Elsevier Ltd. All rights reserved.

Polymer structure-property requirements for stereolithographic 3D printing of soft tissue engineering scaffolds.

PubMed

Mondschein, Ryan J; Kanitkar, Akanksha; Williams, Christopher B; Verbridge, Scott S; Long, Timothy E

2017-09-01

This review highlights the synthesis, properties, and advanced applications of synthetic and natural polymers 3D printed using stereolithography for soft tissue engineering applications. Soft tissue scaffolds are of great interest due to the number of musculoskeletal, cardiovascular, and connective tissue injuries and replacements humans face each year. Accurately replacing or repairing these tissues is challenging due to the variation in size, shape, and strength of different types of soft tissue. With advancing processing techniques such as stereolithography, control of scaffold resolution down to the μm scale is achievable along with the ability to customize each fabricated scaffold to match the targeted replacement tissue. Matching the advanced manufacturing technique to polymer properties as well as maintaining the proper chemical, biological, and mechanical properties for tissue replacement is extremely challenging. This review discusses the design of polymers with tailored structure, architecture, and functionality for stereolithography, while maintaining chemical, biological, and mechanical properties to mimic a broad range of soft tissue types. Copyright © 2017 Elsevier Ltd. All rights reserved.

Engineering complex orthopaedic tissues via strategic biomimicry.

PubMed

Qu, Dovina; Mosher, Christopher Z; Boushell, Margaret K; Lu, Helen H

2015-03-01

The primary current challenge in regenerative engineering resides in the simultaneous formation of more than one type of tissue, as well as their functional assembly into complex tissues or organ systems. Tissue-tissue synchrony is especially important in the musculoskeletal system, wherein overall organ function is enabled by the seamless integration of bone with soft tissues such as ligament, tendon, or cartilage, as well as the integration of muscle with tendon. Therefore, in lieu of a traditional single-tissue system (e.g., bone, ligament), composite tissue scaffold designs for the regeneration of functional connective tissue units (e.g., bone-ligament-bone) are being actively investigated. Closely related is the effort to re-establish tissue-tissue interfaces, which is essential for joining these tissue building blocks and facilitating host integration. Much of the research at the forefront of the field has centered on bioinspired stratified or gradient scaffold designs which aim to recapitulate the structural and compositional inhomogeneity inherent across distinct tissue regions. As such, given the complexity of these musculoskeletal tissue units, the key question is how to identify the most relevant parameters for recapitulating the native structure-function relationships in the scaffold design. Therefore, the focus of this review, in addition to presenting the state-of-the-art in complex scaffold design, is to explore how strategic biomimicry can be applied in engineering tissue connectivity. The objective of strategic biomimicry is to avoid over-engineering by establishing what needs to be learned from nature and defining the essential matrix characteristics that must be reproduced in scaffold design. Application of this engineering strategy for the regeneration of the most common musculoskeletal tissue units (e.g., bone-ligament-bone, muscle-tendon-bone, cartilage-bone) will be discussed in this review. It is anticipated that these exciting efforts will enable integrative and functional repair of soft tissue injuries, and moreover, lay the foundation for the development of composite tissue systems and ultimately, total limb or joint regeneration.

Engineering Complex Orthopaedic Tissues via Strategic Biomimicry

PubMed Central

Qu, Dovina; Mosher, Christopher Z.; Boushell, Margaret K.; Lu, Helen H.

2014-01-01

The primary current challenge in regenerative engineering resides in the simultaneous formation of more than one type of tissue, as well as their functional assembly into complex tissues or organ systems. Tissue-tissue synchrony is especially important in the musculoskeletal system, whereby overall organ function is enabled by the seamless integration of bone with soft tissues such as ligament, tendon, or cartilage, as well as the integration of muscle with tendon. Therefore, in lieu of a traditional single-tissue system (e.g. bone, ligament), composite tissue scaffold designs for the regeneration of functional connective tissue units (e.g. bone-ligament-bone) are being actively investigated. Closely related is the effort to re-establish tissue-tissue interfaces, which is essential for joining these tissue building blocks and facilitating host integration. Much of the research at the forefront of the field has centered on bioinspired stratified or gradient scaffold designs which aim to recapitulate the structural and compositional inhomogeneity inherent across distinct tissue regions. As such, given the complexity of these musculoskeletal tissue units, the key question is how to identify the most relevant parameters for recapitulating the native structure-function relationships in the scaffold design. Therefore, the focus of this review, in addition to presenting the state-of-the-art in complex scaffold design, is to explore how strategic biomimicry can be applied in engineering tissue connectivity. The objective of strategic biomimicry is to avoid over-engineering by establishing what needs to be learned from nature and defining the essential matrix characteristics that must be reproduced in scaffold design. Application of this engineering strategy for the regeneration of the most common musculoskeletal tissue units (e.g. bone-ligament-bone, muscle-tendon-bone, cartilage-bone) will be discussed in this review. It is anticipated that these exciting efforts will enable integrative and functional repair of soft tissue injuries, and moreover, lay the foundation for the development of composite tissue systems and ultimately, total limb or joint regeneration. PMID:25465616

Morphology of the atrioventricular valves and related intraventricular structures in the wild pig (Sus scrofa).

PubMed

Ateş, Sevinç; Karakurum, Emine; Takcı, Lutfi; Başak, Feyza; Kürtül, İbrahim

2017-06-14

Morphology of the atrioventricular valves and the intraventricular related structures were observed and the findings were compared broadly to the literature, in the 7 hearts of the wild pigs (Sus scrofa) by applying macroscopic and microscopic techniques. In all hearts examinated, the tricuspid and mitral valves were precise, composing three and two cusps resepectively. The papillary muscles observed in mammalian heart in general were found in both the ventricles, additionaly there were small unnamed papillary muscles in the left ventricle of the three samples. The septomarginal trabecula and false chords were present in the right ventricles, microscopically possessing myocardial fibers, connective tissue and purkinje cells while the false chords were located in all the left ventricles but the septomarginal trabecula was found in the three samples only. Both the connective tissue and purkinje cells were present in these two structures but the myocardial fibers. Presence of the myocardial fibers in the right ventricle may have an effect on the ventricle geometry.

Regulation of the basement membrane by epithelia generated forces

NASA Astrophysics Data System (ADS)

Tanner, Kandice

2012-12-01

Tumor metastasis involves a progressive loss of tissue architecture and dissolution of structural boundaries between the epithelium and connective tissue. The basement membrane (BM), a specialized network of extracellular matrix proteins forms a barrier that physically restricts pre-invasive lesions such that they remain as local insults. The BM is not a static structure, but one that is constantly regenerated and remodeled in the adult organism. Matrix organization also regulates cell function. Thus alterations in the balance of synthesis, remodeling and proteolytic degradation of the extracellular matrix proteins may contribute to a loss of structural integrity. However, the de novo assembly and maintenance of the complex structural properties of in vivo basement membranes remain elusive. Here, this paper highlights the current understanding on the structural properties and the establishment of the BM, and discusses the potential role of self-generated forces in adult tissue remodeling and the maintenance of the BM as a malignancy suppressor.

Repair of Dense Connective Tissues via Biomaterial-Mediated Matrix Reprogramming of the Wound Interface

PubMed Central

Qu, Feini; Pintauro, Michael P.; Haughan, Joanne; Henning, Elizabeth A.; Esterhai, John L.; Schaer, Thomas P.; Mauck, Robert L.; Fisher, Matthew B.

2014-01-01

Repair of dense connective tissues in adults is limited by their intrinsic hypocellularity and is exacerbated by a dense extracellular matrix (ECM) that impedes cellular migration to and local proliferation at the wound site. Conversely, healing in fetal tissues occurs due in part to an environment conducive to cell mobility and division. Here, we investigated whether the application of a degradative enzyme, collagenase, could reprogram the adult wound margin to a more fetal-like state, and thus abrogate the biophysical impediments that hinder migration and proliferation. We tested this concept using the knee meniscus, a commonly injured structure for which few regenerative approaches exist. To focus delivery and degradation to the wound interface, we developed a system in which collagenase was stored inside poly(ethylene oxide) (PEO) electrospun nanofibers and released upon hydration. Through a series of in vitro and in vivo studies, our findings show that partial digestion of the wound interface improves repair by creating a more compliant and porous microenvironment that expedites cell migration to and/or proliferation at the wound margin. This innovative approach of targeted manipulation of the wound interface, focused on removing the naturally occurring barriers to adult tissue repair, may find widespread application in the treatment of injuries to a variety of dense connective tissues. PMID:25477175

Fluid-Structure Analysis of Opening Phenomena in a Collapsible Airway

NASA Astrophysics Data System (ADS)

Ghadiali, Samir N.; Banks, Julie; Swarts, J. Douglas

2003-11-01

Several physiological functions require the opening of collapsed respiratory airways. For example, the Eustachian tube (ET), which connects the nasopharynx with the middle ear (ME), must be periodically opened to maintain ambient ME pressures. These openings normally occur during swallowing when muscle contraction deforms the surrounding soft tissue. The inability to open the ET results in the most common and costly ear disease in children, Otitis Media. Although tissue-based treatments have been purposed, the influence of the various tissue mechanical properties on flow phenomena has not been investigated. A computational model of ET opening was developed using in-vivo structural data to investigate these fluid-structure interactions. This model accounts for both tissue deformation and the resulting airflow in a non-circular conduit. Results indicate that ET opening is more sensitive to the applied muscle forces than elastic tissue properties. These models have therefore identified how different tissue elements alter ET opening phenomena, which elements should be targeted for treatment and the optimal mechanical properties of these tissue constructs. Research supported by NIH grant DC005345.

Graph Theoretical Framework of Brain Networks in Multiple Sclerosis: A Review of Concepts.

PubMed

Fleischer, Vinzenz; Radetz, Angela; Ciolac, Dumitru; Muthuraman, Muthuraman; Gonzalez-Escamilla, Gabriel; Zipp, Frauke; Groppa, Sergiu

2017-11-01

Network science provides powerful access to essential organizational principles of the human brain. It has been applied in combination with graph theory to characterize brain connectivity patterns. In multiple sclerosis (MS), analysis of the brain networks derived from either structural or functional imaging provides new insights into pathological processes within the gray and white matter. Beyond focal lesions and diffuse tissue damage, network connectivity patterns could be important for closely tracking and predicting the disease course. In this review, we describe concepts of graph theory, highlight novel issues of tissue reorganization in acute and chronic neuroinflammation and address pitfalls with regard to network analysis in MS patients. We further provide an outline of functional and structural connectivity patterns observed in MS, spanning from disconnection and disruption on one hand to adaptation and compensation on the other. Moreover, we link network changes and their relation to clinical disability based on the current literature. Finally, we discuss the perspective of network science in MS for future research and postulate its role in the clinical framework. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

Functional Attachment of Soft Tissues to Bone: Development, Healing, and Tissue Engineering

PubMed Central

Lu, Helen H.; Thomopoulos, Stavros

2014-01-01

Connective tissues such as tendons or ligaments attach to bone across a multitissue interface with spatial gradients in composition, structure, and mechanical properties. These gradients minimize stress concentrations and mediate load transfer between the soft and hard tissues. Given the high incidence of tendon and ligament injuries and the lack of integrative solutions for their repair, interface regeneration remains a significant clinical challenge. This review begins with a description of the developmental processes and the resultant structure-function relationships that translate into the functional grading necessary for stress transfer between soft tissue and bone. It then discusses the interface healing response, with a focus on the influence of mechanical loading and the role of cell-cell interactions. The review continues with a description of current efforts in interface tissue engineering, highlighting key strategies for the regeneration of the soft tissue–to-bone interface, and concludes with a summary of challenges and future directions. PMID:23642244

Clinical anatomy of the pelvic floor.

PubMed

Fritsch, H; Lienemann, A; Brenner, E; Ludwikowski, B

2004-01-01

The study presented here comparing cross-sectional anatomy of the fetal and the adult pelvic connective tissue with the results of modern imaging techniques and actual surgical techniques shows that the classical concepts concerning the subdivision of the pelvic connective tissue and muscles need to be revised. According to clinical requirements, the subdivision of the pelvic cavity into anterior, posterior, and middle compartments is feasible. Predominating connecting tissue structures within the different compartments are: Paravisceral fat pad within the anterior compartment (Fig. 17, I), rectal adventitia or perirectal tissue within the posterior compartment (Fig. 17, II), and uterosacral ligaments within the middle compartment. The nerve-vessel guiding plate can be found in all of these compartments; it starts within the posterior compartment and it ends within the anterior one. It constitutes the morphological border between the anterior and posterior compartments in the male. This border is supplied by the uterosacral ligaments in the female. Whereas in gross anatomy no further border is discernable between anterior and posterior or middle compartment, the rectal fascia (hardly visible in embalmed cadavers) demarcates the rectal adventitia and is one of the most important pelvic structures for the surgeon. In principle, the outlined subdivision of the pelvic connective tissue is identical in the male and in the female; facts that become clear from early human life and that are already established during this period (Fig. 18). The uterus is interposed between the bladder and rectum and subdivides the pelvic peritoneum into two pouches thus establishing the only real difference between male and female pelvic cavity. The preferential direction of the pelvic connective tissue fibers is not changed by the interposition of the uterovaginal complex. The pelvic floor muscles are composed of the portions of the levator ani muscle, the muscles of the cavernous organs and the deep transverse perineal muscle in the male. The latter does not exist in the female. We have clearly shown that the different muscles can already be found in early human life and that they are never intermingled with the muscular walls of the pelvic organs. The levator ani muscle of the female, however, is intermingled with connective tissue long before the female sexual hormones exert influence. We have also shown that the distinct sexual differences within the pelvic floor muscles as well as within the sphincter muscles can already be found in early human life. Both the external urethral and the external anal sphincter muscles are not completely circular. The external anal sphincter is intimately connected with the internal sphincter as well as with the longitudinal muscle. Whereas the innervation and function of the urethral sphincter muscles are mostly clear, cloacal development, innervation, and function of all parts of anal sphincter complex are not completely clarified. As to the support of the pelvic viscera, we believe that intact pelvic floor muscles, an undisturbed topography of the pelvic organs, and an undisturbed perineum are of more importance than the so-called pelvic ligaments. Our hypothesis points to the fact that the support of pelvic viscera is multistructural. Thus in pelvic surgery, a lot of techniques have to be revised with the aim to preserve or to reconstruct all the structures mentioned. This is a multidisciplinary task that can only be solved by cooperation of morphologists, urologists, gynecologists, and coloproctologic surgeons or by creating a multidisciplinary pelvic floor specialist.

Rheology of heterotypic collagen networks.

PubMed

Piechocka, Izabela K; van Oosten, Anne S G; Breuls, Roel G M; Koenderink, Gijsje H

2011-07-11

Collagen fibrils are the main structural element of connective tissues. In many tissues, these fibrils contain two fibrillar collagens (types I and V) in a ratio that changes during tissue development, regeneration, and various diseases. Here we investigate the influence of collagen composition on the structure and rheology of networks of purified collagen I and V, combining fluorescence and atomic force microscopy, turbidimetry, and rheometry. We demonstrate that the network stiffness strongly decreases with increasing collagen V content, even though the network structure does not substantially change. We compare the rheological data with theoretical models for rigid polymers and find that the elasticity is dominated by nonaffine deformations. There is no analytical theory describing this regime, hampering a quantitative interpretation of the influence of collagen V. Our findings are relevant for understanding molecular origins of tissue biomechanics and for guiding rational design of collagenous biomaterials for biomedical applications.

Fibroblastic connective tissue nevus.

PubMed

Velez, Moises J; Billings, Steven D; Weaver, Joshua A

2016-01-01

Fibroblastic connective tissue nevus (FCTN) is a newly recognized, benign cutaneous mesenchymal lesion of fibroblasts/myofibroblastic lineage, which expands the classification of connective tissue nevi. We present three cases of FCTN and discuss significant clinical, morphologic and immunophenotypic overlap with dermatomyofibroma. Our cases were from young women, aged 32, 24 and 10, and presented as 1.2 and 1 cm nodules on the posterior neck and right upper flank, respectively while presenting as a linear plaque of the right posterior thigh in the latter case. The lesions showed a poorly circumscribed proliferation of hypercellular spindle cells arranged in short to longer intersecting fascicles entrapping adnexal structures. Superficial adipose tissue was also entrapped in one case. The spindle cells had fibroblastic features with pale eosinophilic cytoplasmic extensions and inconspicuous nucleoli. The spindle cells were positive for CD34 in two cases. One case was negative for CD34, smooth muscle actin (SMA), desmin and S100. The overall features were consistent with a diagnosis of FCTN. In two cases, we further elucidated the fibroblastic differentiation of the spindle cells in FCTN with electron microscopy, which has not been previously described. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Tissue types (image)

MedlinePlus

... are 4 basic types of tissue: connective tissue, epithelial tissue, muscle tissue, and nervous tissue. Connective tissue supports ... binds them together (bone, blood, and lymph tissues). Epithelial tissue provides a covering (skin, the linings of the ...

Microfabricated 3D Scaffolds for Tissue Engineering Applications

DTIC Science & Technology

2005-01-01

coated layers as sacrificial material for subsequent SU-8 layers (Figure 5b). (a) (b) Figure 5. Four-level SU-8 structure realized with a single...connective tissue progenitor cells on micro-textured polydimethylsiloxane surfaces. Journal of Biomedical Materials Research 2002; 62:499-506. 7. Ratner BD...Applications DISTRIBUTION: Approved for public release, distribution unlimited This paper is part of the following report: TITLE: Materials Research Society

Discriminative staining methods for the nervous system: luxol fast blue--periodic acid-Schiff--hematoxylin triple stain and subsidiary staining methods.

PubMed

Goto, N

1987-09-01

This paper describes a new series of staining methods which can discriminatively demonstrate every structure of the nervous system, including axons and capillaries, in animal and human materials. Methods described in this paper consist of one primary stain, luxol fast blue-periodic acid Schiff-hematoxylin (LPH) and six different subsidiary staining methods. The LPH triple stain can precisely differentiate the following structures: neurons (Nissl bodies, cytoplasm, nuclear membrane and nucleolus), various kinds of nuclei (glia, ependyma, endothelium, leucocyte, connective tissue, etc.), myelin sheaths, neuronal processes (axons and dendrites), reacted glial cell bodies (protoplasmic astrocytes, foamy cells, etc.), blood vessels (arteries, veins and capillaries), meninges, intervening connective tissue, erythrocytes, lipofuscin granules, amyloid bodies, and others. Subsidiary staining methods are also described briefly. Applications are discussed in the context of staining technology and neuromorphological research.

Body wall structure in the starfish Asterias rubens.

PubMed

Blowes, Liisa M; Egertová, Michaela; Liu, Yankai; Davis, Graham R; Terrill, Nick J; Gupta, Himadri S; Elphick, Maurice R

2017-09-01

The body wall of starfish is composed of magnesium calcite ossicles connected by collagenous tissue and muscles and it exhibits remarkable variability in stiffness, which is attributed to the mechanical mutability of the collagenous component. Using the common European starfish Asterias rubens as an experimental animal, here we have employed a variety of techniques to gain new insights into the structure of the starfish body wall. The structure and organisation of muscular and collagenous components of the body wall were analysed using trichrome staining. The muscle system comprises interossicular muscles as well as muscle strands that connect ossicles with the circular muscle layer of the coelomic lining. The collagenous tissue surrounding the ossicle network contains collagen fibres that form loop-shaped straps that wrap around calcite struts near to the surface of ossicles. The 3D architecture of the calcareous endoskeleton was visualised for the first time using X-ray microtomography, revealing the shapes and interactions of different ossicle types. Furthermore, analysis of the anatomical organisation of the ossicles indicates how changes in body shape may be achieved by local contraction/relaxation of interossicular muscles. Scanning synchrotron small-angle X-ray diffraction (SAXD) scans of the starfish aboral body wall and ambulacrum were used to study the collagenous tissue component at the fibrillar level. Collagen fibrils in aboral body wall were found to exhibit variable degrees of alignment, with high levels of alignment probably corresponding to regions where collagenous tissue is under tension. Collagen fibrils in the ambulacrum had a uniformly low degree of orientation, attributed to macrocrimp of the fibrils and the presence of slanted as well as horizontal fibrils connecting antimeric ambulacral ossicles. Body wall collagen fibril D-period lengths were similar to previously reported mammalian D-periods, but were significantly different between the aboral and ambulacral samples. The overlap/D-period length ratio within fibrils was higher than reported for mammalian tissues. Collectively, the data reported here provide new insights into the anatomy of the body wall in A. rubens and a foundation for further studies investigating the structural basis of the mechanical properties of echinoderm body wall tissue composites. © 2017 The Authors. Journal of Anatomy published by John Wiley & Sons Ltd on behalf of Anatomical Society.

The structure-mechanical relationship of palm vascular tissue.

PubMed

Wang, Ningling; Liu, Wangyu; Huang, Jiale; Ma, Ke

2014-08-01

The structure-mechanical relationship of palm sheath is studied with numerical and experimental methods. The cellular structure of the vascular tissue is rebuilt with an image-based reconstruction method and used to create finite element models. The validity of the models is firstly verified with the results from the tensile tests. Then, the cell walls inside each of the specific regions (fiber cap, vessel, xylem, etc.) are randomly removed to obtain virtually imperfect structures. By comparing the magnitudes of performance degradation in the different imperfect structures, the influences of each region on the overall mechanical performances of the vascular tissue are discussed. The longitudinal stiffness and yield strength are sensitive to the defects in the vessel regions. While in the transverse directions (including the radial and tangential directions), the parenchymatous tissue determines the mechanical properties of the vascular tissue. Moreover, the hydraulic, dynamic response and energy absorption behavior of the vascular tissue are numerically explored. The flexibility of natural palm tissue enhances its impact resistance. Under the quasi-static compression, the cell walls connecting the fiber cap and the vessel dissipate more energy. The dominant role of the fiber cap in the plastic energy dissipation under high-speed impact is observed. And the radially-arranged fiber cap also allows the palm tissue to improve its tangential mechanical performances under hydraulic pressure. Copyright © 2014 Elsevier Ltd. All rights reserved.

Acute Achilles Paratendinopathy following Major Injury of the Crural Fascia in a Professional Soccer Player: A Possible Correlation?

PubMed Central

Mattiussi, Gabriele; Turloni, Michele; Baldassi, Pietro Tobia

2016-01-01

Background. The anatomy and mechanical properties of the Crural Fascia (CF), the ubiquitous connective tissue of the posterior region of the leg, have recently been investigated. The most important findings are that (i) the CF may suffer structural damage from indirect trauma, (ii) structural changes of the CF may affect the biomechanics of tissues connected to it, causing myofascial pain syndromes, and (iii) the CF is in anatomical continuity with the Achilles paratenon. Consistent with these points, the authors hypothesize that the onset of acute Achilles paratendinopathy may be related to histological and biomechanical changes of the CF. Case Presentation. A professional male football player suffered an isolated injury of the CF, interposed between the soleus and medial gastrocnemius (an atypical site of injury) with structural connective integrity of the muscles. After participating in the first official match, two and a half months after the trauma, he has unexpectedly demonstrated the clinical picture of acute Achilles paratendinopathy in the previously injured limb. Conclusions. Analysis of this case suggests that the acute Achilles paratendinopathy may be a muscle injury complication from indirect trauma of the calf muscle, if a frank and extensive involvement of the CF were to be ascertained. PMID:27242940

Improvement in skin elasticity in the treatment of cellulite and connective tissue weakness by means of extracorporeal pulse activation therapy.

PubMed

Christ, Christophe; Brenke, Rainer; Sattler, Gerhard; Siems, Werner; Novak, Pavel; Daser, A

2008-01-01

Extracorporeal pulse activation therapy (EPAT), also called extracorporeal acoustic wave therapy, seeks to achieve effective and long-lasting improvement of age-related connective tissue weakness in the extremities, especially in the treatment of unsightly cosmetic skin defects referred to as cellulite. The objective of this study was to stimulate metabolic activity in subcutaneous fat tissue by means of EPAT in order evaluate its effectiveness in enhancing connective tissue firmness and improving skin texture and structure. Fifty-nine women with advanced cellulite were divided into 2 groups; one group of 15 patients received planar acoustic wave treatment for 6 therapy sessions within 3 weeks; a second group of 44 patients received 8 therapy sessions within 4 weeks. Changes in connective tissue were evaluated using the DermaScan C ultrasound system (Cortex Technology, Hadsund, Denmark). Skin elasticity measurements were performed using the DermaLab system (Cortex Technology). Photographs of treated areas were taken at each therapy session and at follow-up sessions. Skin elasticity values gradually improved over the course of EPAT therapy and revealed a 73% increase at the end of therapy. At 3- and 6-month follow-ups, skin elasticity had even improved by 95% and 105%, respectively. Side effects included minor pain for 3 patients during therapy and slight skin reddening. This study confirmed the effects of acoustic wave therapy on biologic tissue, including stimulation of microcirculation and improvement of cell permeability. Ultrasound evaluation demonstrated increased density and firmness in the network of collagen/elastic fibers in the dermis and subcutis. Treatment was most effective in older patients with a long history of cellulite.

Effect of defective collagen synthesis on epithelial implant interface: lathyritic model in dogs. An experimental preliminary study.

PubMed

Cengiz, Murat Inanç; Kirtiloğlu, Tuğrul; Acikgoz, Gökhan; Trisi, Paolo; Wang, Hom-Lay

2012-04-01

Peri-implant mucosa is composed of 2 compartments: a marginal junctional epithelium and a zone of connective tissue attachment. Both structures consist mainly of collagen. Lathyrism is characterized by defective collagen synthesis due to inhibition of lysyl oxidase, an enzyme that is essential for interfibrillar collagen cross-linking. The lathyritic agent beta-aminoproprionitrile (β-APN) is considered a suitable agent to disrupt the connective tissue metabolism. Therefore, the purpose of this study was to assess the effect of defective connective tissue metabolism on epithelial implant interface by using β-APN created chronic lathyrism in the canine model. Two 1-year-old male dogs were included in this study. A β-APN dosage of 5 mg/0.4 mL/volume 100 g/body weight was given to the test dog for 10 months, until lathyritic symptoms developed. After this, the mandibular premolar teeth (p2, p3, p4) of both dogs were atraumatically extracted, and the investigators waited 3 months before implants were placed. In the test dog, 3 implants were placed in the left mandible, and 2 implants were placed in the right mandible. In the control dog, 2 implants were placed in the left mandibular premolar site. The dogs were sacrificed 10 months after healing. Peri-implant tissues obtained from the dogs were examined histomorphologically and histopathologically. Bone to implant contact (BIC) values and bone volumes (BV) were lower in the lathyritic group compared to the control group; however, no statistical significance was found. Significant histologic and histomorphometric changes were observed in peri-implant bone, connective tissue, and peri-implant mucosal width between test and control implants. Defective collagen metabolism such as lathyrism may negatively influence the interface between implant and surrounding soft tissue attachment.

Periodontal regeneration in gingival recession defects.

PubMed

Trombelli, L

1999-02-01

Surgical treatment of gingival recession defects aims at obtaining soft tissue coverage of exposed root surfaces and/or augmentation of gingival tissue dimensions. A variety of protocols have been developed to manage these clinical problems. Since one goal of periodontal therapy is the regeneration of the lost attachment apparatus of the tooth, full restoration of defect should be accomplished following mucogingival procedures. This implies regeneration of all periodontal structures, including formation of new cementum with inserting connective tissue fibers, alveolar bone regeneration and recreation of a functional and aesthetic morphology of the mucogingival complex. Animal and human histological studies have shown that healing at gingiva-root interface following pedicle flaps or free soft tissue grafts generally includes a long junctional epithelium with varying amounts of a new connective tissue attachment in the most apical aspect of the covered root surface. Limited bone regeneration has been observed. Adjunctive use of root conditioning agents and cell excluding, wound-stabilizing devices may amplify regenerative outcomes. Changes in the amount of keratinized tissue, which can significantly affect the aesthetic outcome of treatment, have been shown to depend on the interactions among various tissues involved in the healing process and the selected surgical procedure.

Estimation of tissue stiffness, reflex activity, optimal muscle length and slack length in stroke patients using an electromyography driven antagonistic wrist model.

PubMed

de Gooijer-van de Groep, Karin L; de Vlugt, Erwin; van der Krogt, Hanneke J; Helgadóttir, Áróra; Arendzen, J Hans; Meskers, Carel G M; de Groot, Jurriaan H

2016-06-01

About half of all chronic stroke patients experience loss of arm function coinciding with increased stiffness, reduced range of motion and a flexed wrist due to a change in neural and/or structural tissue properties. Quantitative assessment of these changes is of clinical importance, yet not trivial. The goal of this study was to quantify the neural and structural properties contributing to wrist joint stiffness and to compare these properties between healthy subjects and stroke patients. Stroke patients (n=32) and healthy volunteers (n=14) were measured using ramp-and-hold rotations applied to the wrist joint by a haptic manipulator. Neural (reflexive torque) and structural (connective tissue stiffness and slack lengths and (contractile) optimal muscle lengths) parameters were estimated using an electromyography driven antagonistic wrist model. Kruskal-Wallis analysis with multiple comparisons was used to compare results between healthy subjects, stroke patients with modified Ashworth score of zero and stroke patients with modified Ashworth score of one or more. Stroke patients with modified Ashworth score of one or more differed from healthy controls (P<0.05) by increased tissue stiffness, increased reflexive torque, decreased optimal muscle length and decreased slack length of connective tissue of the flexor muscles. Non-invasive quantitative analysis, including estimation of optimal muscle lengths, enables to identify neural and non-neural changes in chronic stroke patients. Monitoring these changes in time is important to understand the recovery process and to optimize treatment. Copyright © 2016 Elsevier Ltd. All rights reserved.

Man as a living bioreactor: Long-term histological aspects of a mandibular replacement engineered in the patient's own body.

PubMed

Naujokat, H; Açil, Y; Gülses, A; Birkenfeld, F; Wiltfang, J

2018-05-26

In 2016, we reported the world's first reconstruction of a mandibular discontinuity defect using a custom-made bone transplant that had been prefabricated in the gastrocolic omentum using tissue engineering strategies. However, the tissue of an engineered human neomandible has not been evaluated histologically until now. The current study assessed the long-term histological characteristics of biopsies of the neomandible 9months after transplantation. Histological analysis showed an increased amount of vital mineralized bone tissue after 10months, in comparison to biopsies obtained earlier. The engineered bone covered the surface of the bone substitute material but also grew out typical structures of cancellous bone tissue without a core of BioOss. The amount of induced bone tissue was 32% in the biopsy. In addition, the soft tissue showed an alignment of the connective tissue fibres parallel to the trabecular bone. Increasing time and mechanical forces at the mandible led to an increased amount of mineralized tissue and remodelling of the connective tissue fibres after transplantation. Further research should focus on developing advanced scaffold materials, as the outer titanium mesh cage leads to complications. Copyright © 2018 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Glucose Suppresses Biological Ferroelectricity in Aortic Elastin

PubMed Central

Liu, Yuanming; Wang, Yunjie; Chow, Ming-Jay; Chen, Nataly Q.; Ma, Feiyue; Zhang, Yanhang; Li, Jiangyu

2013-01-01

Elastin is an intriguing extracellular matrix protein present in all connective tissues of vertebrates, rendering essential elasticity to connective tissues subjected to repeated physiological stresses. Using piezoresponse force microscopy, we show that the polarity of aortic elastin is switchable by an electrical field, which may be associated with the recently discovered biological ferroelectricity in the aorta. More interestingly, it is discovered that the switching in aortic elastin is largely suppressed by glucose treatment, which appears to freeze the internal asymmetric polar structures of elastin, making it much harder to switch, or suppressing the switching completely. Such loss of ferroelectricity could have important physiological and pathological implications from aging to arteriosclerosis that are closely related to glycation of elastin. PMID:23679639

An Evaluation of Collagen Metabolism in Non Human Primates Associated with the Bion 11 Space Program-Markers of Urinary Collagen Turnover and Muscle Connective Tissue

NASA Technical Reports Server (NTRS)

Vailas, Arthur C.; Martinez, Daniel A.

1999-01-01

Patients exhibiting changes in connective tissue and bone metabolism also show changes in urinary by-products of tissue metabolism. Furthermore, the changes in urinary connective tissue and bone metabolites precede alterations at the tissue macromolecular level. Astronauts and Cosmonauts have also shown suggestive increases in urinary by-products of mineralized and non-mineralized tissue degradation. Thus, the idea of assessing connective tissue and bone response in spaceflight monkeys by measurement of biomarkers in urine has merit. Other investigations of bone and connective histology, cytology and chemistry in the Bion 11 monkeys will allow for further validation of the relationship of urinary biomarkers and tissue response. In future flights the non-invasive procedure of urinary analysis may be useful in early detection of changes in these tissues. The purpose of this grant investigation was to evaluate mineralized and non-mineralized connective tissue responses of non-human primates to microgravity by the non-invasive analysis of urinary biomarkers. Secondly, we also wanted to assess muscle connective tissue adaptive changes in three weight-bearing skeletal muscles: the soleus, media] gastrocnemius and tibialis anterior by obtaining pre-flight and post-flight small biopsy specimens in collaboration with Dr. V. Reggie Edgerton's laboratory at the University of California at Los Angeles.

Chondrocytes, synoviocytes and dermal fibroblasts all express PH-20, a hyaluronidase active at neutral pH

PubMed Central

El Hajjaji, Hafida; Cole, Ada Asbury; Manicourt, Daniel-Henri

2005-01-01

Hyaluronan (HA), an important component of connective tissues, is highly metabolically active, but the mechanisms involved in its catabolism are still largely unknown. We hypothesized that a protein similar to sperm PH-20, the only mammalian hyaluronidase known to be active at neutral pH, could be expressed in connective tissue cells. An mRNA transcript similar to that of PH-20 was found in chondrocytes, synoviocytes, and dermal fibroblasts, and its levels were enhanced upon stimulation with IL-1. In cell layers extracted with Triton X-100 – but not with octylglucoside – and in culture media, a polyclonal antipeptide anti-PH-20 antibody identified protein bands with a molecular weight similar to that of sperm PH-20 (60 to 65 kDa) and exhibiting a hyaluronidase activity at neutral pH. Further, upon stimulation with IL-1, the amounts of the neutral-active hyaluronidase increased in both cell layers and culture media. These findings contribute potential important new insights into the biology of connective tissues. It is likely that PH-20 facilitates cell-receptor-mediated uptake of HA, while overexpression or uncontrolled expression of the enzyme can cause great havoc to connective tissues: not only does HA fragmentation compromise the structural integrity of tissues, but also the HA fragments generated are highly angiogenic and are potent inducers of proinflammatory cytokines. On the other hand, the enzyme activity may account for the progressive depletion of HA seen in osteoarthritis cartilage, a depletion that is believed to play an important role in the apparent irreversibility of this disease process. PMID:15987477

A Novel Esthetic Approach using Connective Tissue Graft for Soft Tissue Defect Following Surgical Excision of Gingival Fibrolipoma

PubMed Central

Parthasarathy, Harinath; Kumar, Praveenkrishna; Gajendran, Priyalochana; Appukuttan, Devapriya

2014-01-01

The aim of the present case report is to evaluate the adjunctive use of a connective tissue graft to overcome soft tissue defects following excision of a gingival fibrolipoma in the aesthetic region. Connective tissue graft has been well documented for treating defects of esthetic concern. However, the literature does not contain many reports on the esthetic clinical outcome following the use of connective tissue graft secondary to excision of soft tissue tumours. A 28-year-old male patient reported with a complaint of a recurrent growth in relation to his lower front tooth region. The lesion which was provisionally diagnosed as fibroma was treated with a complete surgical excision, following which a modified coronally advanced flap and connective tissue graft was adopted to overcome the soft tissue defect. The excised growth was diagnosed histologically as fibrolipoma. One year follow up showed no recurrence of the lesion and good esthetics.The adjunctive use of the connective tissue graft and modified coronally advanced flap predictably yields optimal soft tissue fill and excellent esthetics. Hence, routine use of this procedure may be recommended for surgical excision of soft tissue growths in esthetically sensitive areas. PMID:25584336

A Stochastic Polygons Model for Glandular Structures in Colon Histology Images.

PubMed

Sirinukunwattana, Korsuk; Snead, David R J; Rajpoot, Nasir M

2015-11-01

In this paper, we present a stochastic model for glandular structures in histology images of tissue slides stained with Hematoxylin and Eosin, choosing colon tissue as an example. The proposed Random Polygons Model (RPM) treats each glandular structure in an image as a polygon made of a random number of vertices, where the vertices represent approximate locations of epithelial nuclei. We formulate the RPM as a Bayesian inference problem by defining a prior for spatial connectivity and arrangement of neighboring epithelial nuclei and a likelihood for the presence of a glandular structure. The inference is made via a Reversible-Jump Markov chain Monte Carlo simulation. To the best of our knowledge, all existing published algorithms for gland segmentation are designed to mainly work on healthy samples, adenomas, and low grade adenocarcinomas. One of them has been demonstrated to work on intermediate grade adenocarcinomas at its best. Our experimental results show that the RPM yields favorable results, both quantitatively and qualitatively, for extraction of glandular structures in histology images of normal human colon tissues as well as benign and cancerous tissues, excluding undifferentiated carcinomas.

The diagnostic value of plasma N-terminal connective tissue growth factor levels in children with heart failure.

PubMed

Li, Gang; Song, Xueqing; Xia, Jiyi; Li, Jing; Jia, Peng; Chen, Pengyuan; Zhao, Jian; Liu, Bin

2017-01-01

The aim of this study was to assess the diagnostic value of plasma N-terminal connective tissue growth factor in children with heart failure. Methods and results Plasma N-terminal connective tissue growth factor was determined in 61 children, including 41 children with heart failure, 20 children without heart failure, and 30 healthy volunteers. The correlations between plasma N-terminal connective tissue growth factor levels and clinical parameters were investigated. Moreover, the diagnostic value of N-terminal connective tissue growth factor levels was evaluated. Compared with healthy volunteers and children without heart failure, plasma N-terminal connective tissue growth factor levels were significantly elevated in those with heart failure (p0.05), but it obviously improved the ability of diagnosing heart failure in children, as demonstrated by the integrated discrimination improvement (6.2%, p=0.013) and net re-classification improvement (13.2%, p=0.017) indices. Plasma N-terminal connective tissue growth factor is a promising diagnostic biomarker for heart failure in children.

Osteoimmunology: the study of the relationship between the immune system and bone tissue.

PubMed

Arboleya, Luis; Castañeda, Santos

2013-01-01

Bone tissue is a highly regulated structure, which plays an essential role in various physiological functions. Through autocrine and paracrine mechanisms, bone tissue is involved in hematopoiesis, influencing the fate of hematopoietic stem cells. There are a number of molecules shared by bone cells and immune system cells indicating that there are multiple connections between the immune system and bone tissue. In order to pool all the knowledge concerning both systems, a new discipline known under the term «osteoimmunology» has been developed. Their progress in recent years has been exponential and allowed us to connect and increase our knowledge in areas not seemingly related such as rheumatoid erosion, postmenopausal osteoporosis, bone metastases or periodontal disease. In this review, we have tried to summarize the most important advances that have occurred in the last decade, especially in those areas of interest related to rheumatology. Copyright © 2013 Elsevier España, S.L. All rights reserved.

Topological and organizational properties of the products of house-keeping and tissue-specific genes in protein-protein interaction networks.

PubMed

Lin, Wen-Hsien; Liu, Wei-Chung; Hwang, Ming-Jing

2009-03-11

Human cells of various tissue types differ greatly in morphology despite having the same set of genetic information. Some genes are expressed in all cell types to perform house-keeping functions, while some are selectively expressed to perform tissue-specific functions. In this study, we wished to elucidate how proteins encoded by human house-keeping genes and tissue-specific genes are organized in human protein-protein interaction networks. We constructed protein-protein interaction networks for different tissue types using two gene expression datasets and one protein-protein interaction database. We then calculated three network indices of topological importance, the degree, closeness, and betweenness centralities, to measure the network position of proteins encoded by house-keeping and tissue-specific genes, and quantified their local connectivity structure. Compared to a random selection of proteins, house-keeping gene-encoded proteins tended to have a greater number of directly interacting neighbors and occupy network positions in several shortest paths of interaction between protein pairs, whereas tissue-specific gene-encoded proteins did not. In addition, house-keeping gene-encoded proteins tended to connect with other house-keeping gene-encoded proteins in all tissue types, whereas tissue-specific gene-encoded proteins also tended to connect with other tissue-specific gene-encoded proteins, but only in approximately half of the tissue types examined. Our analysis showed that house-keeping gene-encoded proteins tend to occupy important network positions, while those encoded by tissue-specific genes do not. The biological implications of our findings were discussed and we proposed a hypothesis regarding how cells organize their protein tools in protein-protein interaction networks. Our results led us to speculate that house-keeping gene-encoded proteins might form a core in human protein-protein interaction networks, while clusters of tissue-specific gene-encoded proteins are attached to the core at more peripheral positions of the networks.

Qualitative assessment of connective tissue graft with epithelial component. A microsurgical periodontal plastic surgical technique for soft tissue esthetics.

PubMed

Rossi, Roberto; Pilloni, Andrea; Morales, Regina Santos

2009-01-01

Connective tissue grafts have been used successfully in the treatment of gingival recession. In the mid 80s and late 90s, the periodontal literature presented various techniques such as free gingival grafts, pedicle flaps, subepithelial connective tissue grafts, acellular dermal matrix grafts, and guided tissue regeneration to cover denuded root surfaces. Currently, connective tissue grafting is a reliable treatment for esthetic root coverage. This paper presents a qualitative assessment of a surgical technique that uses a connective tissue graft, including a portion of epithelium in the shape of the defect. This procedure enhances the healing of the covered root surface, increases the thickness of the soft tissue and improves esthetics. The criteria used for evaluation were: color, volume, texture, and blending. This evaluation demonstrated encouraging results from an esthetic viewpoint.

Scleroderma

MedlinePlus

... of diseases that cause abnormal growth of connective tissue. Connective tissue is the material inside your body that gives ... joints. Symptoms of scleroderma include Calcium deposits in connective tissues Raynaud's phenomenon, a narrowing of blood vessels in ...

Mutations in B3GALT6, which Encodes a Glycosaminoglycan Linker Region Enzyme, Cause a Spectrum of Skeletal and Connective Tissue Disorders

PubMed Central

Nakajima, Masahiro; Mizumoto, Shuji; Miyake, Noriko; Kogawa, Ryo; Iida, Aritoshi; Ito, Hironori; Kitoh, Hiroshi; Hirayama, Aya; Mitsubuchi, Hiroshi; Miyazaki, Osamu; Kosaki, Rika; Horikawa, Reiko; Lai, Angeline; Mendoza-Londono, Roberto; Dupuis, Lucie; Chitayat, David; Howard, Andrew; Leal, Gabriela F.; Cavalcanti, Denise; Tsurusaki, Yoshinori; Saitsu, Hirotomo; Watanabe, Shigehiko; Lausch, Ekkehart; Unger, Sheila; Bonafé, Luisa; Ohashi, Hirofumi; Superti-Furga, Andrea; Matsumoto, Naomichi; Sugahara, Kazuyuki; Nishimura, Gen; Ikegawa, Shiro

2013-01-01

Proteoglycans (PGs) are a major component of the extracellular matrix in many tissues and function as structural and regulatory molecules. PGs are composed of core proteins and glycosaminoglycan (GAG) side chains. The biosynthesis of GAGs starts with the linker region that consists of four sugar residues and is followed by repeating disaccharide units. By exome sequencing, we found that B3GALT6 encoding an enzyme involved in the biosynthesis of the GAG linker region is responsible for a severe skeletal dysplasia, spondyloepimetaphyseal dysplasia with joint laxity type 1 (SEMD-JL1). B3GALT6 loss-of-function mutations were found in individuals with SEMD-JL1 from seven families. In a subsequent candidate gene study based on the phenotypic similarity, we found that B3GALT6 is also responsible for a connective tissue disease, Ehlers-Danlos syndrome (progeroid form). Recessive loss-of-function mutations in B3GALT6 result in a spectrum of disorders affecting a broad range of skeletal and connective tissues characterized by lax skin, muscle hypotonia, joint dislocation, and spinal deformity. The pleiotropic phenotypes of the disorders indicate that B3GALT6 plays a critical role in a wide range of biological processes in various tissues, including skin, bone, cartilage, tendon, and ligament. PMID:23664117

Repair of dense connective tissues via biomaterial-mediated matrix reprogramming of the wound interface.

PubMed

Qu, Feini; Pintauro, Michael P; Haughan, Joanne E; Henning, Elizabeth A; Esterhai, John L; Schaer, Thomas P; Mauck, Robert L; Fisher, Matthew B

2015-01-01

Repair of dense connective tissues in adults is limited by their intrinsic hypocellularity and is exacerbated by a dense extracellular matrix (ECM) that impedes cellular migration to and local proliferation at the wound site. Conversely, healing in fetal tissues occurs due in part to an environment conducive to cell mobility and division. Here, we investigated whether the application of a degradative enzyme, collagenase, could reprogram the adult wound margin to a more fetal-like state, and thus abrogate the biophysical impediments that hinder migration and proliferation. We tested this concept using the knee meniscus, a commonly injured structure for which few regenerative approaches exist. To focus delivery and degradation to the wound interface, we developed a system in which collagenase was stored inside poly(ethylene oxide) (PEO) electrospun nanofibers and released upon hydration. Through a series of in vitro and in vivo studies, our findings show that partial digestion of the wound interface improves repair by creating a more compliant and porous microenvironment that expedites cell migration to and/or proliferation at the wound margin. This innovative approach of targeted manipulation of the wound interface, focused on removing the naturally occurring barriers to adult tissue repair, may find widespread application in the treatment of injuries to a variety of dense connective tissues. Copyright © 2014 Elsevier Ltd. All rights reserved.

Blood Flow Changes in Subsynovial Connective Tissue on Contrast-Enhanced Ultrasonography in Patients With Carpal Tunnel Syndrome Before and After Surgical Decompression.

PubMed

Motomiya, Makoto; Funakoshi, Tadanao; Ishizaka, Kinya; Nishida, Mutsumi; Matsui, Yuichiro; Iwasaki, Norimasa

2017-11-24

Although qualitative alteration of the subsynovial connective tissue in the carpal tunnel is considered to be one of the most important factors in the pathophysiologic mechanisms of carpal tunnel syndrome (CTS), little information is available about the microcirculation in the subsynovial connective tissue in patients with CTS. The aims of this study were to use contrast-enhanced ultrasonography (US) to evaluate blood flow in the subsynovial connective tissue proximal to the carpal tunnel in patients with CTS before and after carpal tunnel release. The study included 15 volunteers and 12 patients with CTS. The blood flow in the subsynovial connective tissue and the median nerve was evaluated preoperatively and at 1, 2, and 3 months postoperatively using contrast-enhanced US. The blood flow in the subsynovial connective tissue was higher in the patients with CTS than in the volunteers. In the patients with CTS, there was a significant correlation between the blood flow in the subsynovial connective tissue and the median nerve (P = .01). The blood flow in both the subsynovial connective tissue and the median nerve increased markedly after carpal tunnel release. Our results suggest that increased blood flow in the subsynovial connective tissue may play a role in the alteration of the microcirculation within the median nerve related to the pathophysiologic mechanisms of CTS. The increase in the blood flow in the subsynovial connective tissue during the early postoperative period may contribute to the changes in intraneural circulation, and these changes may lead to neural recovery. © 2017 by the American Institute of Ultrasound in Medicine.

Needle-based polarization-sensitive OCT of breast tumor (Conference Presentation)

NASA Astrophysics Data System (ADS)

Villiger, Martin; Lorenser, Dirk; McLaughlin, Robert A.; Quirk, Bryden C.; Kirk, Rodney W.; Bouma, Brett E.; Sampson, David D.

2016-03-01

OCT imaging through miniature needle probes has extended the range of OCT and enabled structural imaging deep inside breast tissue, with the potential to assist in the intraoperative assessment of tumor margins. However, in many situations, scattering contrast alone is insufficient to clearly identify and delineate malignant areas. Here, we present a portable, depth-encoded polarization-sensitive OCT system, connected to a miniature needle probe. From the measured polarization states we constructed the tissue Mueller matrix at each sample location and improved the accuracy of the measured polarization states through incoherent averaging before retrieving the depth-resolved tissue birefringence. With the Mueller matrix at hand, additional polarization properties such as depolarization are readily available. We then imaged freshly excised breast tissue from a patient undergoing lumpectomy. The reconstructed local retardation highlighted regions of connective tissue, which exhibited birefringence due to the abundance of collagen fibers, and offered excellent contrast to areas of malignant tissue, which exhibited less birefringence due to their different tissue composition. Results were validated against co-located histology sections. The combination of needle-based imaging with the complementary contrast provided by polarization-sensitive analysis offers a powerful instrument for advanced tissue imaging and has potential to aid in the assessment of tumor margins during the resection of breast cancer.

Intraluminal fibrosis in interstitial lung disorders.

PubMed Central

Basset, F.; Ferrans, V. J.; Soler, P.; Takemura, T.; Fukuda, Y.; Crystal, R. G.

1986-01-01

The histopathologic and ultrastructural features of intraluminal organizing and fibrotic changes were studied in open lung biopsies and autopsy specimens from 373 patients with interstitial lung disorders, including hypersensitivity pneumonitis (n = 44), idiopathic pulmonary fibrosis (n = 92), collagen-vascular diseases (n = 20), chronic eosinophilic pneumonia (n = 10), pulmonary histiocytosis X (n-90), pulmonary sarcoidosis (n = 62), pneumoconioses (n = 25), Legionnaire's disease (n = 5), drug- and toxin-induced pneumonitis (n = 4), radiation-induced pneumonitis (n = 2), lymphangioleiomyomatosis (n = 11), and chronic organizing pneumonia of unknown cause (n = 8). Three patterns of intraluminal organization and fibrosis were recognized: 1) intraluminal buds, which partially filled the alveoli, alveolar ducts and/or distal bronchioles; 2) obliterative changes, in which loose connective tissue masses obliterated the lumens of alveoli, alveolar ducts or distal bronchioles, and 3) mural incorporation of previously intraluminal connective tissue masses, which fused with alveolar, alveolar ductal, or bronchiolar structures and frequently became reepithelialized. All three patterns had common morphologic features, suggesting that, regardless of their severity, they resulted from a common pathogenetic mechanism, ie, the migration of activated connective tissue cells, through defects in the epithelial lining and its basement membrane, from the interstitial into the intraluminal compartment. Intraluminal buds were observed most frequently in hypersensitivity pneumonitis, chronic eosinophilic pneumonia, and organizing pneumonia of unknown cause. Mural incorporation and, to a lesser extent, obliterative changes were observed in most interstitial disorders and were very prominent in idiopathic pulmonary fibrosis. Mural incorporation and obliterative changes play an important role in pulmonary remodeling, especially when several adjacent alveoli and/or other air spaces are involved. Under these circumstances, intraluminal organization can mediate the fusion of adjacent alveolar structures by intraluminal connective tissue. Images Figure 15 Figure 9 Figure 10 Figure 16 Figure 17 Figure 1 Figure 2 Figure 3 Figure 4 Figure 18 Figure 5 Figure 6 Figure 7 Figure 8 Figure 19 Figure 20 Figure 11 Figure 12 Figure 13 Figure 14 PMID:3953768

Glycomics expression analysis of sulfated glycosaminoglycans of human colorectal cancer tissues and non-neoplastic mucosa by electrospray ionization mass spectrometry.

PubMed

Marolla, Ana Paula Cleto; Waisberg, Jaques; Saba, Gabriela Tognini; Waisberg, Daniel Reis; Margeotto, Fernando Beani; Pinhal, Maria Aparecida da Silva

2015-01-01

To determine the presence of glycosaminoglycans in the extracellular matrix of connective tissue from neoplastic and non-neoplastic colorectal tissues, since it has a central role in tumor development and progression. Tissue samples from neoplastic and non-neoplastic colorectal tissues were obtained from 64 operated patients who had colorectal carcinoma with no distant metastases. Expressions of heparan sulphate, chondroitin sulphate, dermatan sulphate and their fragments were analyzed by electrospray ionization mass spectrometry, with the technique for extraction and quantification of glycosaminoglycans after proteolysis and electrophoresis. The statistical analysis included mean, standard deviation, and Student'st test. The glycosaminoglycans extracted from colorectal tissue showed three electrophoretic bands in agarose gel. Electrospray ionization mass spectrometry showed characteristic disaccharide fragments from glycosaminoglycans, indicating their structural characterization in the tissues analyzed. Some peaks in the electrospray ionization mass spectrometry were not characterized as fragments of sugars, indicating the presence of fragments of the protein structure of proteoglycans generated during the glycosaminoglycan purification. The average amount of chondroitin and dermatan increased in the neoplastic tissue compared to normal tissue (p=0.01). On the other hand, the average amount of heparan decreased in the neoplastic tissue compared to normal tissue (p= 0.03). The method allowed the determination of the glycosaminoglycans structural profile in colorectal tissue from neoplastic and non-neoplastic colorectal tissue. Neoplastic tissues showed greater amounts of chondroitin sulphate and dermatan sulphate compared to non-neoplastic tissues, while heparan sulphate was decreased in neoplastic tissues.

Pectus Excavatum and Heritable Disorders of the Connective Tissue

PubMed Central

Tocchioni, Francesca; Ghionzoli, Marco; Messineo, Antonio; Romagnoli, Paolo

2013-01-01

Pectus excavatum, the most frequent congenital chest wall deformity, may be rarely observed as a sole deformity or as a sign of an underlying connective tissue disorder. To date, only few studies have described correlations between this deformity and heritable connective tissue disorders such as Marfan, Ehlers-Danlos, Poland, MASS (Mitral valve prolapse, not progressive Aortic enlargement, Skeletal and Skin alterations) phenotype among others. When concurring with connective tissue disorder, cardiopulmonary and vascular involvement may be associated to the thoracic defect. Ruling out the concomitance of pectus excavatum and connective tissue disorders, therefore, may have a direct implication both on surgical outcome and long term prognosis. In this review we focused on biological bases of connective tissue disorders which may be relevant to the pathogenesis of pectus excavatum, portraying surgical and clinical implication of their concurrence. PMID:24198927

Connective tissue growth factor is expressed in bone marrow stromal cells and promotes interleukin-7-dependent B lymphopoiesis.

PubMed

Cheung, Laurence C; Strickland, Deborah H; Howlett, Meegan; Ford, Jette; Charles, Adrian K; Lyons, Karen M; Brigstock, David R; Goldschmeding, Roel; Cole, Catherine H; Alexander, Warren S; Kees, Ursula R

2014-07-01

Hematopoiesis occurs in a complex bone marrow microenvironment in which bone marrow stromal cells provide critical support to the process through direct cell contact and indirectly through the secretion of cytokines and growth factors. We report that connective tissue growth factor (Ctgf, also known as Ccn2) is highly expressed in murine bone marrow stromal cells. In contrast, connective tissue growth factor is barely detectable in unfractionated adult bone marrow cells. While connective tissue growth factor has been implicated in hematopoietic malignancies, and is known to play critical roles in skeletogenesis and regulation of bone marrow stromal cells, its role in hematopoiesis has not been described. Here we demonstrate that the absence of connective tissue growth factor in mice results in impaired hematopoiesis. Using a chimeric fetal liver transplantation model, we show that absence of connective tissue growth factor has an impact on B-cell development, in particular from pro-B to more mature stages, which is linked to a requirement for connective tissue growth factor in bone marrow stromal cells. Using in vitro culture systems, we demonstrate that connective tissue growth factor potentiates B-cell proliferation and promotes pro-B to pre-B differentiation in the presence of interleukin-7. This study provides a better understanding of the functions of connective tissue growth factor within the bone marrow, showing the dual regulatory role of the growth factor in skeletogenesis and in stage-specific B lymphopoiesis. Copyright© Ferrata Storti Foundation.

Connective tissue growth factor is expressed in bone marrow stromal cells and promotes interleukin-7-dependent B lymphopoiesis

PubMed Central

Cheung, Laurence C.; Strickland, Deborah H.; Howlett, Meegan; Ford, Jette; Charles, Adrian K.; Lyons, Karen M.; Brigstock, David R.; Goldschmeding, Roel; Cole, Catherine H.; Alexander, Warren S.; Kees, Ursula R.

2014-01-01

Hematopoiesis occurs in a complex bone marrow microenvironment in which bone marrow stromal cells provide critical support to the process through direct cell contact and indirectly through the secretion of cytokines and growth factors. We report that connective tissue growth factor (Ctgf, also known as Ccn2) is highly expressed in murine bone marrow stromal cells. In contrast, connective tissue growth factor is barely detectable in unfractionated adult bone marrow cells. While connective tissue growth factor has been implicated in hematopoietic malignancies, and is known to play critical roles in skeletogenesis and regulation of bone marrow stromal cells, its role in hematopoiesis has not been described. Here we demonstrate that the absence of connective tissue growth factor in mice results in impaired hematopoiesis. Using a chimeric fetal liver transplantation model, we show that absence of connective tissue growth factor has an impact on B-cell development, in particular from pro-B to more mature stages, which is linked to a requirement for connective tissue growth factor in bone marrow stromal cells. Using in vitro culture systems, we demonstrate that connective tissue growth factor potentiates B-cell proliferation and promotes pro-B to pre-B differentiation in the presence of interleukin-7. This study provides a better understanding of the functions of connective tissue growth factor within the bone marrow, showing the dual regulatory role of the growth factor in skeletogenesis and in stage-specific B lymphopoiesis. PMID:24727816

An Evaluation of Collagen Metabolism in Non Human Primates Associated with the Bion 11 Space Program-Markers of Urinary Collagen Turnover and Muscle Connective Tissue

NASA Technical Reports Server (NTRS)

Vailas, Arthur C.; Martinez, Daniel A.

1999-01-01

Patients exhibiting changes in connective tissue and bone metabolism also show changes in urinary by-products of tissue metabolism. Furthermore, the changes in urinary connective tissue and bone metabolites precede alterations at the tissue macromolecular level. Astronauts and Cosmonauts have also shown suggestive increases in urinary by-products of mineralized and non-mineralized tissue degradation. Thus, the idea of assessing connective tissue and bone response in spaceflight monkeys by measurement of biomarkers in urine has merit. Other investigations of bone and connective histology, cytology and chemistry in the Bion 11 monkeys will allow for further validation of the relationship of urinary biomarkers and tissue response. In future flights the non-invasive procedure of urinary analysis may be useful in early detection of changes in these tissues. Purpose: The purpose of this grant investigation was to evaluate mineralized and non-mineralized connective tissue responses of non-human primates to microgravity by the non-invasive analysis of urinary biomarkers. Secondly, we also wanted to assess muscle connective tissue adaptive changes in three weight-bearing skeletal muscles: the soleus, medial gastrocnemius and tibialis anterior by obtaining pre-flight and post-flight small biopsy specimens in collaboration with Dr. V. Reggie Edgerton's laboratory at the University of California at Los Angeles.

Architecture of the sperm whale forehead facilitates ramming combat.

PubMed

Panagiotopoulou, Olga; Spyridis, Panagiotis; Mehari Abraha, Hyab; Carrier, David R; Pataky, Todd C

2016-01-01

Herman Melville's novel Moby Dick was inspired by historical instances in which large sperm whales (Physeter macrocephalus L.) sank 19th century whaling ships by ramming them with their foreheads. The immense forehead of sperm whales is possibly the largest, and one of the strangest, anatomical structures in the animal kingdom. It contains two large oil-filled compartments, known as the "spermaceti organ" and "junk," that constitute up to one-quarter of body mass and extend one-third of the total length of the whale. Recognized as playing an important role in echolocation, previous studies have also attributed the complex structural configuration of the spermaceti organ and junk to acoustic sexual selection, acoustic prey debilitation, buoyancy control, and aggressive ramming. Of these additional suggested functions, ramming remains the most controversial, and the potential mechanical roles of the structural components of the spermaceti organ and junk in ramming remain untested. Here we explore the aggressive ramming hypothesis using a novel combination of structural engineering principles and probabilistic simulation to determine if the unique structure of the junk significantly reduces stress in the skull during quasi-static impact. Our analyses indicate that the connective tissue partitions in the junk reduce von Mises stresses across the skull and that the load-redistribution functionality of the former is insensitive to moderate variation in tissue material parameters, the thickness of the partitions, and variations in the location and angle of the applied load. Absence of the connective tissue partitions increases skull stresses, particularly in the rostral aspect of the upper jaw, further hinting of the important role the architecture of the junk may play in ramming events. Our study also found that impact loads on the spermaceti organ generate lower skull stresses than an impact on the junk. Nevertheless, whilst an impact on the spermaceti organ would reduce skull stresses, it would also cause high compressive stresses on the anterior aspect of the organ and the connective tissue case, possibly making these structures more prone to failure. This outcome, coupled with the facts that the spermaceti organ houses sensitive and essential sonar producing structures and the rostral portion of junk, rather than the spermaceti organ, is frequently a site of significant scarring in mature males suggest that whales avoid impact with the spermaceti organ. Although the unique structure of the junk certainly serves multiple functions, our results are consistent with the hypothesis that the structure also evolved to function as a massive battering ram during male-male competition.

Genome-wide strategies identify downstream target genes of chick connective tissue-associated transcription factors.

PubMed

Orgeur, Mickael; Martens, Marvin; Leonte, Georgeta; Nassari, Sonya; Bonnin, Marie-Ange; Börno, Stefan T; Timmermann, Bernd; Hecht, Jochen; Duprez, Delphine; Stricker, Sigmar

2018-03-29

Connective tissues support organs and play crucial roles in development, homeostasis and fibrosis, yet our understanding of their formation is still limited. To gain insight into the molecular mechanisms of connective tissue specification, we selected five zinc-finger transcription factors - OSR1, OSR2, EGR1, KLF2 and KLF4 - based on their expression patterns and/or known involvement in connective tissue subtype differentiation. RNA-seq and ChIP-seq profiling of chick limb micromass cultures revealed a set of common genes regulated by all five transcription factors, which we describe as a connective tissue core expression set. This common core was enriched with genes associated with axon guidance and myofibroblast signature, including fibrosis-related genes. In addition, each transcription factor regulated a specific set of signalling molecules and extracellular matrix components. This suggests a concept whereby local molecular niches can be created by the expression of specific transcription factors impinging on the specification of local microenvironments. The regulatory network established here identifies common and distinct molecular signatures of limb connective tissue subtypes, provides novel insight into the signalling pathways governing connective tissue specification, and serves as a resource for connective tissue development. © 2018. Published by The Company of Biologists Ltd.

Connective tissue spectrum abnormalities associated with spontaneous cerebrospinal fluid leaks: a prospective study.

PubMed

Reinstein, Eyal; Pariani, Mitchel; Bannykh, Serguei; Rimoin, David L; Schievink, Wouter I

2013-04-01

We aimed to assess the frequency of connective tissue abnormalities among patients with cerebrospinal fluid (CSF) leaks in a prospective study using a large cohort of patients. We enrolled a consecutive group of 50 patients, referred for consultation because of CSF leak. All patients have been carefully examined for the presence of connective tissue abnormalities, and based on findings, patients underwent genetic testing. Ancillary diagnostic studies included echocardiography, eye exam, and histopathological examinations of skin and dura biopsies in selected patients. We identified nine patients with heritable connective tissue disorders, including Marfan syndrome, Ehlers-Danlos syndrome and other unclassified forms. In seven patients, spontaneous CSF leak was the first noted manifestation of the genetic disorder. We conclude that spontaneous CSF leaks are associated with a spectrum of connective tissue abnormalities and may be the first noted clinical presentation of the genetic disorder. We propose that there is a clinical basis for considering spontaneous CSF leak as a clinical manifestation of heritable connective tissue disorders, and we suggest that patients with CSF leaks should be screened for connective tissue and vascular abnormalities.

The Effect of Tissue Entrapment on Screw Loosening at the Implant/Abutment Interface of External- and Internal-Connection Implants: An In Vitro Study.

PubMed

Zeno, Helios A; Buitrago, Renan L; Sternberger, Sidney S; Patt, Marisa E; Tovar, Nick; Coelho, Paulo; Kurtz, Kenneth S; Tuminelli, Frank J

2016-04-01

To compare the removal of torque values of machined implant abutment connections (internal and external) with and without soft tissue entrapment using an in vitro model. Thirty external- and 30 internal-connection implants were embedded in urethane dimethacrylate. Porcine tissue was prepared and measured to thicknesses of 0.5 and 1.0 mm. Six groups (n = 10) were studied: External- and internal-connection implants with no tissue (control), 0.5, and 1.0 mm of tissue were entrapped at the implant/abutment interface. Abutments were inserted to 20 Ncm for all six groups. Insertion torque values were recorded using a digital torque gauge. All groups were then immersed in 1 M NaOH for 48 hours to dissolve tissue. Subsequent reverse torque measurements were recorded. Mean and standard deviation were determined for each group, and one-way ANOVA and Bonferroni test were used for statistical analysis. All 60 specimens achieved a 20-Ncm insertion torque, despite tissue entrapment. Reverse torque measurements for external connection displayed a statistically significant difference (p < 0.05) between all groups with mean reverse torque values for the control (13.71 ± 1.4 Ncm), 0.5 mm (7.83 ± 2.4 Ncm), and 1.0 mm tissue entrapment (2.29 ± 1.4 Ncm) groups. Some statistically significant differences (p < 0.05) were found between internal-connection groups. In all specimens, tissue did not completely dissolve after 48 hours. External-connection implants were significantly affected by tissue entrapment; the thicker the tissue, the lower the reverse torque values noted. Internal-connection implants were less affected by tissue entrapment. © 2015 by the American College of Prosthodontists.

Functional Connectivity in Islets of Langerhans from Mouse Pancreas Tissue Slices

PubMed Central

Stožer, Andraž; Gosak, Marko; Dolenšek, Jurij; Perc, Matjaž; Marhl, Marko; Rupnik, Marjan Slak; Korošak, Dean

2013-01-01

We propose a network representation of electrically coupled beta cells in islets of Langerhans. Beta cells are functionally connected on the basis of correlations between calcium dynamics of individual cells, obtained by means of confocal laser-scanning calcium imaging in islets from acute mouse pancreas tissue slices. Obtained functional networks are analyzed in the light of known structural and physiological properties of islets. Focusing on the temporal evolution of the network under stimulation with glucose, we show that the dynamics are more correlated under stimulation than under non-stimulated conditions and that the highest overall correlation, largely independent of Euclidean distances between cells, is observed in the activation and deactivation phases when cells are driven by the external stimulus. Moreover, we find that the range of interactions in networks during activity shows a clear dependence on the Euclidean distance, lending support to previous observations that beta cells are synchronized via calcium waves spreading throughout islets. Most interestingly, the functional connectivity patterns between beta cells exhibit small-world properties, suggesting that beta cells do not form a homogeneous geometric network but are connected in a functionally more efficient way. Presented results provide support for the existing knowledge of beta cell physiology from a network perspective and shed important new light on the functional organization of beta cell syncitia whose structural topology is probably not as trivial as believed so far. PMID:23468610

Connective tissue growth factor (CTGF) and cancer progression.

PubMed

Chu, Chia-Yu; Chang, Cheng-Chi; Prakash, Ekambaranellore; Kuo, Min-Liang

2008-11-01

Connective tissue growth factor (CTGF) is a member of the CCN family of secreted, matrix-associated proteins encoded by immediate early genes that play various roles in angiogenesis and tumor growth. CCN family proteins share uniform modular structure which mediates various cellular functions such as regulation of cell division, chemotaxis, apoptosis, adhesion, motility, angiogenesis, neoplastic transformation, and ion transport. Recently, CTGF expression has been shown to be associated with tumor development and progression. There is growing body of evidence that CTGF may regulate cancer cell migration, invasion, angiogenesis, and anoikis. In this review, we will highlight the influence of CTGF expression on the biological behavior and progression of various cancer cells, as well as its regulation on various types of protein signals and their mechanisms.

The connective tissue component of the caprine arthritis-encephalitis syndrome.

PubMed Central

Crawford, T. B.; Adams, D. S.; Sande, R. D.; Gorham, J. R.; Henson, J. B.

1980-01-01

The gross and microscopic connective tissue lesions in 12 goats with caprine arthritis-encephalitis (CAE) are described, including those from which a virus (CAEV) was isolated. Lesions were most often associated with synovial-lined structures including joints, tendon sheaths, and bursae, and were typified by synovial cell proliferations, subsynovial mononuclear cell infiltration, the presence of fibrin, fibrinous concretions, necrosis, and mineralization. Extrasynovial lesions were located in kidneys, vessels, and brain. The inflammatory infiltrates in these organs were predominantly mononuclear. Amyloid was also found in liver, spleen, and kidney. Microbiologic techniques failed to demonstrate any bacteria, mycoplasma, or chlamydia in the lesions. Images Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 1 Figure 2 Figure 3 Figure 4 PMID:7406019

Multilayer porous UHMWPE scaffolds for bone defects replacement.

PubMed

Maksimkin, A V; Senatov, F S; Anisimova, N Yu; Kiselevskiy, M V; Zalepugin, D Yu; Chernyshova, I V; Tilkunova, N A; Kaloshkin, S D

2017-04-01

Reconstruction of the structural integrity of the damaged bone tissue is an urgent problem. UHMWPE may be potentially used for the manufacture of porous implants simulating as closely as possible the porous cancellous bone tissue. But the extremely high molecular weight of the polymer does not allow using traditional methods of foaming. Porous and multilayer UHMWPE scaffolds with nonporous bulk layer and porous layer that mimics cancellous bone architecture were obtained by solid-state mixing, thermopressing and washing in subcritical water. Structural and mechanical properties of the samples were studied. Porous UHMWPE samples were also studied in vitro and in vivo. The pores of UHMWPE scaffold are open and interconnected. Volume porosity of the obtained samples was 79±2%; the pore size range was 80-700μm. Strong connection of the two layers in multilayer UHMWPE scaffolds was observed with decreased number of fusion defects. Functionality of implants based on multilayer UHMWPE scaffolds is provided by the fixation of scaffolds in the bone defect through ingrowths of the connective tissue into the pores, which ensures the maintenance of the animals' mobility. Copyright © 2016 Elsevier B.V. All rights reserved.

Protein Equilibration through Somatic Ring Canals in Drosophila

PubMed Central

McLean, Peter F.; Cooley, Lynn

2013-01-01

Although intercellular bridges resulting from incomplete cytokinesis were discovered in somatic Drosophila tissues decades ago, the impact of these structures on intercellular communication and tissue biology is largely unknown. In this work, we demonstrate that the ~250 nm diameter somatic ring canals permit diffusion of cytoplasmic contents between connected cells and across mitotic clone boundaries, and enable the equilibration of protein between transcriptionally mosaic follicle cells in the Drosophila ovary. We obtained similar, though more restricted, results in the larval imaginal discs. Our work illustrates the lack of cytoplasmic autonomy in these tissues and suggests a role for somatic ring canals in promoting homogeneous protein expression within the tissue. PMID:23704373

Comparative histology of mouse, rat, and human pelvic ligaments.

PubMed

Iwanaga, Ritsuko; Orlicky, David J; Arnett, Jameson; Guess, Marsha K; Hurt, K Joseph; Connell, Kathleen A

2016-11-01

The uterosacral (USL) and cardinal ligaments (CL) provide support to the uterus and pelvic organs, and the round ligaments (RL) maintain their position in the pelvis. In women with pelvic organ prolapse (POP), the connective tissue, smooth muscle, vasculature, and innervation of the pelvic support structures are altered. Rodents are commonly used animal models for POP research. However, the pelvic ligaments have not been defined in these animals. In this study, we hypothesized that the gross anatomy and histological composition of pelvic ligaments in rodents and humans are similar. We performed an extensive literature search for anatomical and histological descriptions of the pelvic support ligaments in rodents. We also performed anatomical dissections of the pelvis to define anatomical landmarks in relation to the ligaments. In addition, we identified the histological components of the pelvic ligaments and performed quantitative analysis of the smooth muscle bundles and connective tissue of the USL and RL. The anatomy of the USL, CL, and RL and their anatomical landmarks are similar in mice, rats, and humans. All species contain the same cellular components and have similar histological architecture. However, the cervical portion of the mouse USL and RL contain more smooth muscle and less connective tissue compared with rat and human ligaments. The pelvic support structures of rats and mice are anatomically and histologically similar to those of humans. We propose that both mice and rats are appropriate, cost-effective models for directed studies in POP research.

The structure of interfibrillar proteoglycan bridges (‘shape modules’) in extracellular matrix of fibrous connective tissues and their stability in various chemical environments

PubMed Central

SCOTT, JOHN E.; THOMLINSON, ALISON M.

1998-01-01

Collagen fibrils in extracellular matrices of connective tissues (tendon, cornea, etc.) are bridged and linked by the anionic glycosaminoglycans (AGAGs) of the small proteoglycans (decoron, etc.). It was proposed that these bridges and ties maintain the collagen fibril dispositions in relation to each other, helping to define tissue shape, and hence called shape modules. This investigation describes chemical and physicochemical conditions in which these structures are stable and what treatments cause their disruption. The effects on fixed and unfixed sections of tendon, cornea, lung and ear from rat, mouse and rabbit of pH, electrolyte concentration, EDTA, mercaptoethanol, hydrogen peroxide, free radicals, periodate, acetylation, urea, nonionic detergent and organic solvents were assessed by staining with Cupromeronic blue or Alcec blue in CEC techniques to localise AGAG bridges or their disintegration products. Ca2+ was not involved in the structures, oxidation/reduction had no effect and Triton X100, a nonionic detergent did not damage them. They were stable between pH 4.5 and 9.5. Periodate as a glycol-cleaving reagent did not affect them. High concentrations of urea (>2.0 m) and MgCl2 (0.5 m) disrupted the tissues. The combination of Triton and urea at concentrations too low to cause damage separately was disruptive. Free radicals in periodate solutions were damaging. Organic solvents caused collapse and rearrangements of the AGAG filaments. Acetylation caused considerable disruption of shape modules. Dermochondan but not keratan sulphate AGAGs were removed by treatment with NaOH. After fixing with glutaraldehyde only free radical and NaOH treatments were severely disruptive of shape modules. The results are compatible with a previously proposed structure for the shape modules, stabilised by hydrophobic and hydrogen bonding. PMID:9688505

Effect of houttuynia cordata aetherolea on adiponectin and connective tissue growth factor in a rat model of diabetes mellitus.

PubMed

Wang, Hai-Ying; Bao, Jun-Lu

2012-03-01

To determine the effect of Houttuynia cordata Aetherolea on connective tissue growth factor and adiponectin in a rat model of diabetes mellitus (DM). DM was induced in rats using streptozotocin (STZ) and high glucose-lipid animal feed. Animals were then treated with Houttuynia cordata Aetherolea for 8 weeks. Changes in connective tissue growth factor and adiponectin levels in rats were observed. Connective tissue growth factor and adiponectin levels in rats with DM improved after Houttuynia cordata Aetherolea treatment. Houttuynia cordata Aetherolea had a positive effect on rats with DM by reducing levels of connective tissue growth factor and increasing adiponectin levels.

Hyaluronan (HA) interacting proteins RHAMM and hyaluronidase impact prostate cancer cell behavior and invadopodia formation in 3D HA-based hydrogels.

PubMed

Gurski, Lisa A; Xu, Xian; Labrada, Lyana N; Nguyen, Ngoc T; Xiao, Longxi; van Golen, Kenneth L; Jia, Xinqiao; Farach-Carson, Mary C

2012-01-01

To study the individual functions of hyaluronan interacting proteins in prostate cancer (PCa) motility through connective tissues, we developed a novel three-dimensional (3D) hyaluronic acid (HA) hydrogel assay that provides a flexible, quantifiable, and physiologically relevant alternative to current methods. Invasion in this system reflects the prevalence of HA in connective tissues and its role in the promotion of cancer cell motility and tissue invasion, making the system ideal to study invasion through bone marrow or other HA-rich connective tissues. The bio-compatible cross-linking process we used allows for direct encapsulation of cancer cells within the gel where they adopt a distinct, cluster-like morphology. Metastatic PCa cells in these hydrogels develop fingerlike structures, "invadopodia", consistent with their invasive properties. The number of invadopodia, as well as cluster size, shape, and convergence, can provide a quantifiable measure of invasive potential. Among candidate hyaluronan interacting proteins that could be responsible for the behavior we observed, we found that culture in the HA hydrogel triggers invasive PCa cells to differentially express and localize receptor for hyaluronan mediated motility (RHAMM)/CD168 which, in the absence of CD44, appears to contribute to PCa motility and invasion by interacting with the HA hydrogel components. PCa cell invasion through the HA hydrogel also was found to depend on the activity of hyaluronidases. Studies shown here reveal that while hyaluronidase activity is necessary for invadopodia and inter-connecting cluster formation, activity alone is not sufficient for acquisition of invasiveness to occur. We therefore suggest that development of invasive behavior in 3D HA-based systems requires development of additional cellular features, such as activation of motility associated pathways that regulate formation of invadopodia. Thus, we report development of a 3D system amenable to dissection of biological processes associated with cancer cell motility through HA-rich connective tissues.

Experiment K-6-02. Biomedical, biochemical and morphological alterations of muscle and dense, fibrous connective tissues during 14 days of spaceflight

NASA Technical Reports Server (NTRS)

Vailas, A.; Zernicke, R.; Grindeland, R.; Kaplanski, A.

1990-01-01

Findings on the connective tissue response to short-term space flight (12 days) are discussed. Specifically, data regarding the biochemical, biomechanical and morphological characteristics of selected connective tissues (humerus, vertebral body, tendon and skeletal muscle) of growing rats is given. Results are given concerning the humerus cortical bone, the vertebral bone, nutritional effects on bone biomechanical properties, and soft tense fiber connective tissue response.

3D MRI Modeling of Thin and Spatially Complex Soft Tissue Structures without Shrinkage: Lamprey Myosepta as an Example.

PubMed

Wood, Bradley M; Jia, Guang; Carmichael, Owen; McKlveen, Kevin; Homberger, Dominique G

2018-05-12

3D imaging techniques enable the non-destructive analysis and modeling of complex structures. Among these, MRI exhibits good soft tissue contrast, but is currently less commonly used for non-clinical research than x-ray CT, even though the latter requires contrast-staining that shrinks and distorts soft tissues. When the objective is the creation of a realistic and complete 3D model of soft tissue structures, MRI data are more demanding to acquire and visualize and require extensive post-processing because they comprise non-cubic voxels with dimensions that represent a trade-off between tissue contrast and image resolution. Therefore, thin soft tissue structures with complex spatial configurations are not always visible in a single MRI dataset, so that standard segmentation techniques are not sufficient for their complete visualization. By using the example of the thin and spatially complex connective tissue myosepta in lampreys, we developed a workflow protocol for the selection of the appropriate parameters for the acquisition of MRI data and for the visualization and 3D modeling of soft tissue structures. This protocol includes a novel recursive segmentation technique for supplementing missing data in one dataset with data from another dataset to produce realistic and complete 3D models. Such 3D models are needed for the modeling of dynamic processes, such as the biomechanics of fish locomotion. However, our methodology is applicable to the visualization of any thin soft tissue structures with complex spatial configurations, such as fasciae, aponeuroses, and small blood vessels and nerves, for clinical research and the further exploration of tensegrity. This article is protected by copyright. All rights reserved. © 2018 Wiley Periodicals, Inc.

Connective tissue diseases, multimorbidity and the ageing lung.

PubMed

Spagnolo, Paolo; Cordier, Jean-François; Cottin, Vincent

2016-05-01

Connective tissue diseases encompass a wide range of heterogeneous disorders characterised by immune-mediated chronic inflammation often leading to tissue damage, collagen deposition and possible loss of function of the target organ. Lung involvement is a common complication of connective tissue diseases. Depending on the underlying disease, various thoracic compartments can be involved but interstitial lung disease is a major contributor to morbidity and mortality. Interstitial lung disease, pulmonary hypertension or both are found most commonly in systemic sclerosis. In the elderly, the prevalence of connective tissue diseases continues to rise due to both longer life expectancy and more effective and better-tolerated treatments. In the geriatric population, connective tissue diseases are almost invariably accompanied by age-related comorbidities, and disease- and treatment-related complications, which contribute to the significant morbidity and mortality associated with these conditions, and complicate treatment decision-making. Connective tissue diseases in the elderly represent a growing concern for healthcare providers and an increasing burden of global health resources worldwide. A better understanding of the mechanisms involved in the regulation of the immune functions in the elderly and evidence-based guidelines specifically designed for this patient population are instrumental to improving the management of connective tissue diseases in elderly patients. Copyright ©ERS 2016.

Advances in biomimetic regeneration of elastic matrix structures

PubMed Central

Sivaraman, Balakrishnan; Bashur, Chris A.

2012-01-01

Elastin is a vital component of the extracellular matrix, providing soft connective tissues with the property of elastic recoil following deformation and regulating the cellular response via biomechanical transduction to maintain tissue homeostasis. The limited ability of most adult cells to synthesize elastin precursors and assemble them into mature crosslinked structures has hindered the development of functional tissue-engineered constructs that exhibit the structure and biomechanics of normal native elastic tissues in the body. In diseased tissues, the chronic overexpression of proteolytic enzymes can cause significant matrix degradation, to further limit the accumulation and quality (e.g., fiber formation) of newly deposited elastic matrix. This review provides an overview of the role and importance of elastin and elastic matrix in soft tissues, the challenges to elastic matrix generation in vitro and to regenerative elastic matrix repair in vivo, current biomolecular strategies to enhance elastin deposition and matrix assembly, and the need to concurrently inhibit proteolytic matrix disruption for improving the quantity and quality of elastogenesis. The review further presents biomaterial-based options using scaffolds and nanocarriers for spatio-temporal control over the presentation and release of these biomolecules, to enable biomimetic assembly of clinically relevant native elastic matrix-like superstructures. Finally, this review provides an overview of recent advances and prospects for the application of these strategies to regenerating tissue-type specific elastic matrix structures and superstructures. PMID:23355960

Coordinated Development of Muscles and Tendon-Like Structures: Early Interactions in the Drosophila Leg.

PubMed

Soler, Cedric; Laddada, Lilia; Jagla, Krzysztof

2016-01-01

The formation of the musculoskeletal system is a remarkable example of tissue assembly. In both vertebrates and invertebrates, precise connectivity between muscles and skeleton (or exoskeleton) via tendons or equivalent structures is fundamental for movement and stability of the body. The molecular and cellular processes underpinning muscle formation are well-established and significant advances have been made in understanding tendon development. However, the mechanisms contributing to proper connection between these two tissues have received less attention. Observations of coordinated development of tendons and muscles suggest these tissues may interact during the different steps in their development. There is growing evidence that, depending on animal model and muscle type, these interactions can take place from progenitor induction to the final step of the formation of the musculoskeletal system. Here, we briefly review and compare the mechanisms behind muscle and tendon interaction throughout the development of vertebrates and Drosophila before going on to discuss our recent findings on the coordinated development of muscles and tendon-like structures in Drosophila leg. By altering apodeme formation (the functional Drosophila equivalent of tendons in vertebrates) during the early steps of leg development, we affect the spatial localization of subsequent myoblasts. These findings provide the first evidence of the developmental impact of early interactions between muscle and tendon-like precursors, and confirm the appendicular Drosophila muscle system as a valuable model for studying these processes.

Coordinated Development of Muscles and Tendon-Like Structures: Early Interactions in the Drosophila Leg

PubMed Central

Soler, Cedric; Laddada, Lilia; Jagla, Krzysztof

2016-01-01

The formation of the musculoskeletal system is a remarkable example of tissue assembly. In both vertebrates and invertebrates, precise connectivity between muscles and skeleton (or exoskeleton) via tendons or equivalent structures is fundamental for movement and stability of the body. The molecular and cellular processes underpinning muscle formation are well-established and significant advances have been made in understanding tendon development. However, the mechanisms contributing to proper connection between these two tissues have received less attention. Observations of coordinated development of tendons and muscles suggest these tissues may interact during the different steps in their development. There is growing evidence that, depending on animal model and muscle type, these interactions can take place from progenitor induction to the final step of the formation of the musculoskeletal system. Here, we briefly review and compare the mechanisms behind muscle and tendon interaction throughout the development of vertebrates and Drosophila before going on to discuss our recent findings on the coordinated development of muscles and tendon-like structures in Drosophila leg. By altering apodeme formation (the functional Drosophila equivalent of tendons in vertebrates) during the early steps of leg development, we affect the spatial localization of subsequent myoblasts. These findings provide the first evidence of the developmental impact of early interactions between muscle and tendon-like precursors, and confirm the appendicular Drosophila muscle system as a valuable model for studying these processes. PMID:26869938

Glycomics expression analysis of sulfated glycosaminoglycans of human colorectal cancer tissues and non-neoplastic mucosa by electrospray ionization mass spectrometry

PubMed Central

Marolla, Ana Paula Cleto; Waisberg, Jaques; Saba, Gabriela Tognini; Waisberg, Daniel Reis; Margeotto, Fernando Beani; Pinhal, Maria Aparecida da Silva

2015-01-01

ABSTRACT Objective To determine the presence of glycosaminoglycans in the extracellular matrix of connective tissue from neoplastic and non-neoplastic colorectal tissues, since it has a central role in tumor development and progression. Methods Tissue samples from neoplastic and non-neoplastic colorectal tissues were obtained from 64 operated patients who had colorectal carcinoma with no distant metastases. Expressions of heparan sulphate, chondroitin sulphate, dermatan sulphate and their fragments were analyzed by electrospray ionization mass spectrometry, with the technique for extraction and quantification of glycosaminoglycans after proteolysis and electrophoresis. The statistical analysis included mean, standard deviation, and Student’s t test. Results The glycosaminoglycans extracted from colorectal tissue showed three electrophoretic bands in agarose gel. Electrospray ionization mass spectrometry showed characteristic disaccharide fragments from glycosaminoglycans, indicating their structural characterization in the tissues analyzed. Some peaks in the electrospray ionization mass spectrometry were not characterized as fragments of sugars, indicating the presence of fragments of the protein structure of proteoglycans generated during the glycosaminoglycan purification. The average amount of chondroitin and dermatan increased in the neoplastic tissue compared to normal tissue (p=0.01). On the other hand, the average amount of heparan decreased in the neoplastic tissue compared to normal tissue (p= 0.03). Conclusion The method allowed the determination of the glycosaminoglycans structural profile in colorectal tissue from neoplastic and non-neoplastic colorectal tissue. Neoplastic tissues showed greater amounts of chondroitin sulphate and dermatan sulphate compared to non-neoplastic tissues, while heparan sulphate was decreased in neoplastic tissues. PMID:26761548

Altered structural brain changes and neurocognitive performance in pediatric HIV.

PubMed

Yadav, Santosh K; Gupta, Rakesh K; Garg, Ravindra K; Venkatesh, Vimala; Gupta, Pradeep K; Singh, Alok K; Hashem, Sheema; Al-Sulaiti, Asma; Kaura, Deepak; Wang, Ena; Marincola, Francesco M; Haris, Mohammad

2017-01-01

Pediatric HIV patients often suffer with neurodevelopmental delay and subsequently cognitive impairment. While tissue injury in cortical and subcortical regions in the brain of adult HIV patients has been well reported there is sparse knowledge about these changes in perinatally HIV infected pediatric patients. We analyzed cortical thickness, subcortical volume, structural connectivity, and neurocognitive functions in pediatric HIV patients and compared with those of pediatric healthy controls. With informed consent, 34 perinatally infected pediatric HIV patients and 32 age and gender matched pediatric healthy controls underwent neurocognitive assessment and brain magnetic resonance imaging (MRI) on a 3 T clinical scanner. Altered cortical thickness, subcortical volumes, and abnormal neuropsychological test scores were observed in pediatric HIV patients. The structural network connectivity analysis depicted lower connection strengths, lower clustering coefficients, and higher path length in pediatric HIV patients than healthy controls. The network betweenness and network hubs in cortico-limbic regions were distorted in pediatric HIV patients. The findings suggest that altered cortical and subcortical structures and regional brain connectivity in pediatric HIV patients may contribute to deficits in their neurocognitive functions. Further, longitudinal studies are required for better understanding of the effect of HIV pathogenesis on brain structural changes throughout the brain development process under standard ART treatment.

Autofluorescence multiphoton microscopy for visualization of tissue morphology and cellular dynamics in murine and human airways.

PubMed

Kretschmer, Sarah; Pieper, Mario; Hüttmann, Gereon; Bölke, Torsten; Wollenberg, Barbara; Marsh, Leigh M; Garn, Holger; König, Peter

2016-08-01

The basic understanding of inflammatory airway diseases greatly benefits from imaging the cellular dynamics of immune cells. Current imaging approaches focus on labeling specific cells to follow their dynamics but fail to visualize the surrounding tissue. To overcome this problem, we evaluated autofluorescence multiphoton microscopy for following the motion and interaction of cells in the airways in the context of tissue morphology. Freshly isolated murine tracheae from healthy mice and mice with experimental allergic airway inflammation were examined by autofluorescence multiphoton microscopy. In addition, fluorescently labeled ovalbumin and fluorophore-labeled antibodies were applied to visualize antigen uptake and to identify specific cell populations, respectively. The trachea in living mice was imaged to verify that the ex vivo preparation reflects the in vivo situation. Autofluorescence multiphoton microscopy was also tested to examine human tissue from patients in short-term tissue culture. Using autofluorescence, the epithelium, underlying cells, and fibers of the connective tissue, as well as blood vessels, were identified in isolated tracheae. Similar structures were visualized in living mice and in the human airway tissue. In explanted murine airways, mobile cells were localized within the tissue and we could follow their migration, interactions between individual cells, and their phagocytic activity. During allergic airway inflammation, increased number of eosinophil and neutrophil granulocytes were detected that moved within the connective tissue and immediately below the epithelium without damaging the epithelial cells or connective tissues. Contacts between granulocytes were transient lasting 3 min on average. Unexpectedly, prolonged interactions between granulocytes and antigen-uptaking cells were observed lasting for an average of 13 min. Our results indicate that autofluorescence-based imaging can detect previously unknown immune cell interactions in the airways. The method also holds the potential to be used during diagnostic procedures in humans if integrated into a bronchoscope.

Initial Biochemical Characterization of Cells Derived from Human Periodontium and Their In vitro Response to Platelet-Derived Growth Factor, Epidermal Growth Factor and Transforming Growth Factor-Beta

DTIC Science & Technology

1988-05-01

Periodontal disease is characterized by a loss of connective tissue...obtained for bone cells and fibroblasts. • " S,. O. ipr’ 0 II. LITERATURE REVIEW A . Periodontal Regeneration Periodontal disease is characterized by a ...fracture are felt to involve a similar sequence of cellular events. Since periodontal disease also involves the loss of soft tissue structures, such

3D surface rendered MR images of the brain and its vasculature.

PubMed

Cline, H E; Lorensen, W E; Souza, S P; Jolesz, F A; Kikinis, R; Gerig, G; Kennedy, T E

1991-01-01

Both time-of-flight and phase contrast magnetic resonance angiography images are combined with stationary tissue images to provide data depicting two contrast relationships yielding intrinsic discrimination of brain matter and flowing blood. A computer analysis is based on nearest neighbor segmentation and the connection between anatomical structures to partition the images into different tissue categories: from which, high resolution brain parenchymal and vascular surfaces are constructed and rendered in juxtaposition, aiding in surgical planning.

Mutations in B3GALT6, which encodes a glycosaminoglycan linker region enzyme, cause a spectrum of skeletal and connective tissue disorders.

PubMed

Nakajima, Masahiro; Mizumoto, Shuji; Miyake, Noriko; Kogawa, Ryo; Iida, Aritoshi; Ito, Hironori; Kitoh, Hiroshi; Hirayama, Aya; Mitsubuchi, Hiroshi; Miyazaki, Osamu; Kosaki, Rika; Horikawa, Reiko; Lai, Angeline; Mendoza-Londono, Roberto; Dupuis, Lucie; Chitayat, David; Howard, Andrew; Leal, Gabriela F; Cavalcanti, Denise; Tsurusaki, Yoshinori; Saitsu, Hirotomo; Watanabe, Shigehiko; Lausch, Ekkehart; Unger, Sheila; Bonafé, Luisa; Ohashi, Hirofumi; Superti-Furga, Andrea; Matsumoto, Naomichi; Sugahara, Kazuyuki; Nishimura, Gen; Ikegawa, Shiro

2013-06-06

Proteoglycans (PGs) are a major component of the extracellular matrix in many tissues and function as structural and regulatory molecules. PGs are composed of core proteins and glycosaminoglycan (GAG) side chains. The biosynthesis of GAGs starts with the linker region that consists of four sugar residues and is followed by repeating disaccharide units. By exome sequencing, we found that B3GALT6 encoding an enzyme involved in the biosynthesis of the GAG linker region is responsible for a severe skeletal dysplasia, spondyloepimetaphyseal dysplasia with joint laxity type 1 (SEMD-JL1). B3GALT6 loss-of-function mutations were found in individuals with SEMD-JL1 from seven families. In a subsequent candidate gene study based on the phenotypic similarity, we found that B3GALT6 is also responsible for a connective tissue disease, Ehlers-Danlos syndrome (progeroid form). Recessive loss-of-function mutations in B3GALT6 result in a spectrum of disorders affecting a broad range of skeletal and connective tissues characterized by lax skin, muscle hypotonia, joint dislocation, and spinal deformity. The pleiotropic phenotypes of the disorders indicate that B3GALT6 plays a critical role in a wide range of biological processes in various tissues, including skin, bone, cartilage, tendon, and ligament. Copyright © 2013 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

Mueller matrix approach for probing multifractality in the underlying anisotropic connective tissue

NASA Astrophysics Data System (ADS)

Das, Nandan Kumar; Dey, Rajib; Ghosh, Nirmalya

2016-09-01

Spatial variation of refractive index (RI) in connective tissues exhibits multifractality, which encodes useful morphological and ultrastructural information about the disease. We present a spectral Mueller matrix (MM)-based approach in combination with multifractal detrended fluctuation analysis (MFDFA) to exclusively pick out the signature of the underlying connective tissue multifractality through the superficial epithelium layer. The method is based on inverse analysis on selected spectral scattering MM elements encoding the birefringence information on the anisotropic connective tissue. The light scattering spectra corresponding to the birefringence carrying MM elements are then subjected to the Born approximation-based Fourier domain preprocessing to extract ultrastructural RI fluctuations of anisotropic tissue. The extracted RI fluctuations are subsequently analyzed via MFDFA to yield the multifractal tissue parameters. The approach was experimentally validated on a simple tissue model comprising of TiO2 as scatterers of the superficial isotropic layer and rat tail collagen as an underlying anisotropic layer. Finally, the method enabled probing of precancer-related subtle alterations in underlying connective tissue ultrastructural multifractality from intact tissues.

Morphogenesis and growth of the soft tissue and cartilage of the vomeronasal organ in pigs

PubMed Central

Salazar, Ignacio; Lombardero, Matilde; Cifuentes, José M; Quinteiro, Pablo Sánchez; Alemañ, Nuria

2003-01-01

The morphology of the soft tissue and supporting cartilage of the vomeronasal organ of the fetal pig was studied from early stages to term. Specimens obtained from an abattoir were aged by crown-to-rump distance. Series of transverse sections show that some time before birth all structures – cartilage, connective tissue, blood vessels, nerves, glands and epithelia – are well developed and very similar in appearance to those of the adult. Furthermore, in transmission electron microscopy photomicrographs obtained at this stage the vomeronasal glands exhibit secretory activity. PMID:12846472

Ultrasound skin tightening.

PubMed

Minkis, Kira; Alam, Murad

2014-01-01

Ultrasound skin tightening is a noninvasive, nonablative method that allows for energy deposition into the deep dermal and subcutaneous tissue while avoiding epidermal heating. Ultrasound coagulation is confined to arrays of 1-mm(3) zones that include the superficial musculoaponeurotic system and connective tissue. This technology gained approval from the Food and Drug Administration as the first energy-based skin "lifting" device, specifically for lifting lax tissue on the neck, submentum, and eyebrows. Ultrasound has the unique advantage of direct visualization of treated structures during treatment. Ultrasound is a safe and efficacious treatment for mild skin tightening and lifting. Copyright © 2014 Elsevier Inc. All rights reserved.

Alveolar ridge augmentation by connective tissue grafting using a pouch method and modified connective tissue technique: A prospective study.

PubMed

Agarwal, Ashish; Gupta, Narinder Dev

2015-01-01

Localized alveolar ridge defect may create physiological and pathological problems. Developments in surgical techniques have made it simpler to change the configuration of a ridge to create a more aesthetic and more easily cleansable shape. The purpose of this study was to compare the efficacy of alveolar ridge augmentation using a subepithelial connective tissue graft in pouch and modified connective tissue graft technique. In this randomized, double blind, parallel and prospective study, 40 non-smoker individuals with 40 class III alveolar ridge defects in maxillary anterior were randomly divided in two groups. Group I received modified connective tissue graft, while group II were treated with subepithelial connective tissue graft in pouch technique. The defect size was measured in its horizontal and vertical dimension by utilizing a periodontal probe in a stone cast at base line, after 3 months, and 6 months post surgically. Analysis of variance and Bonferroni post-hoc test were used for statistical analysis. A two-tailed P < 0.05 was considered to be statistically significant. Mean values in horizontal width after 6 months were 4.70 ± 0.87 mm, and 4.05 ± 0.89 mm for group I and II, respectively. Regarding vertical heights, obtained mean values were 4.75 ± 0.97 mm and 3.70 ± 0.92 mm for group I and group II, respectively. Within the limitations of this study, connective tissue graft proposed significantly more improvement as compare to connective tissue graft in pouch.

An iterative hyperelastic parameters reconstruction for breast cancer assessment

NASA Astrophysics Data System (ADS)

Mehrabian, Hatef; Samani, Abbas

2008-03-01

In breast elastography, breast tissues usually undergo large compressions resulting in significant geometric and structural changes, and consequently nonlinear mechanical behavior. In this study, an elastography technique is presented where parameters characterizing tissue nonlinear behavior is reconstructed. Such parameters can be used for tumor tissue classification. To model the nonlinear behavior, tissues are treated as hyperelastic materials. The proposed technique uses a constrained iterative inversion method to reconstruct the tissue hyperelastic parameters. The reconstruction technique uses a nonlinear finite element (FE) model for solving the forward problem. In this research, we applied Yeoh and Polynomial models to model the tissue hyperelasticity. To mimic the breast geometry, we used a computational phantom, which comprises of a hemisphere connected to a cylinder. This phantom consists of two types of soft tissue to mimic adipose and fibroglandular tissues and a tumor. Simulation results show the feasibility of the proposed method in reconstructing the hyperelastic parameters of the tumor tissue.

The Rationale for Joint Mobilization.

ERIC Educational Resources Information Center

Burkhardt, Sandy

This paper presents an overview of the functions of connective tissue and the mechanisms of joint injury and contracture formation in relation to therapeutic exercise. The components of connective tissue operation are explained, including fibroblasts, macrophages, plasma cells, and collagen. An examination of the histology of connective tissue as…

CELLULAR CONTROL OF CONNECTIVE TISSUE MATRIX TENSION†

PubMed Central

Langevin, Helene M.; Nedergaard, Maiken; Howe, Alan

2013-01-01

The biomechanical behavior of connective tissue in response to stretching is generally attributed to the molecular composition and organization of its extracellular matrix. It also is becoming apparent that fibroblasts play an active role in regulating connective tissue tension. In response to static stretching of the tissue, fibroblasts expand within minutes by actively remodeling their cytoskeleton. This dynamic change in fibroblast shape contributes to the drop in tissue tension that occurs during viscoelastic relaxation. We propose that this response of fibroblasts plays a role in regulating extracellular fluid flow into the tissue, and protects against swelling when the matrix is stretched. This article reviews the evidence supporting possible mechanisms underlying this response including autocrine purinergic signaling. We also discuss fibroblast regulation of connective tissue tension with respect to lymphatic flow, immune function and cancer. PMID:23444198

Imaging of connective tissue diseases of the head and neck

PubMed Central

2016-01-01

We review the imaging appearance of connective tissue diseases of the head and neck. Bilateral sialadenitis and dacryoadenitis are seen in Sjögren’s syndrome; ankylosis of the temporo-mandibular joint with sclerosis of the crico-arytenoid joint are reported in rheumatoid arthritis and lupus panniculitis with atypical infection are reported in patients with systemic lupus erythematosus. Relapsing polychondritis shows subglottic stenosis, prominent ear and saddle nose; progressive systemic sclerosis shows osteolysis of the mandible, fibrosis of the masseter muscle with calcinosis of the subcutaneous tissue and dermatomyositis/polymyositis shows condylar erosions and autoimmune thyroiditis. Vascular thrombosis is reported in antiphospholipid antibodies syndrome; cervical lymphadenopathy is seen in adult-onset Still’s disease, and neuropathy with thyroiditis reported in mixed connective tissue disorder. Imaging is important to detect associated malignancy with connective tissue disorders. Correlation of the imaging findings with demographic data and clinical findings are important for the diagnosis of connective tissue disorders. PMID:26988082

Cerebriform connective tissue nevus of lumbar.

PubMed

Chen, Jinbo; Chen, Liuqing; Duan, Yiqun; Li, Dongsheng; Dong, Bilin

2015-02-01

Connective tissue nevi represents a kind of hamartoma, and coalescence of the lesions in a cerebriform mode in the lumbar region without Proteus syndrome is rarely seen. Here, we report a 26-year-old woman presenting with nodules and plaques in her left lumbar region of 26 years in duration. Histopathological examination and Masson-trichrome stain showed increased dermal collagen bundles in a haphazard array. The diagnosis of connective tissue nevi was made. This is the first case report on cerebriform connective tissue nevi without Proteus syndrome in the lumbar region. © 2014 Japanese Dermatological Association.

Association between antinuclear antibody titers and connective tissue diseases in a Rheumatology Department.

PubMed

Menor Almagro, Raúl; Rodríguez Gutiérrez, Juan Francisco; Martín-Martínez, María Auxiliadora; Rodríguez Valls, María José; Aranda Valera, Concepción; de la Iglesia Salgado, José Luís

To determine the dilution titles at antinuclear antibodies (ANA) by indirect immunofluorescence observed in cell substrate HEp-2 and its association with the diagnosis of systemic connective tissue disease in ANA test requested by a Rheumatology Unit. Samples of patients attended for the first time in the rheumatology unit, without prior ANA test, between January 2010 and December 2012 were selected. The dilution titers, immunofluorescence patterns and antigen specificity were recorded. In January 2015 the diagnosis of the patients were evaluated and classified in systemic disease connective tissue (systemic lupus erythematosus, Sjögren's syndrome, systemic sclerosis, undifferentiated connective, antiphospholipid syndrome, mixed connective tissue and inflammatory myophaty) or not systemic disease connective tissue. A total of 1282 ANA tests requested by the Rheumatology Unit in subjects without previous study, 293 were positive, predominance of women (81.9%). Patients with systemic connective tissue disease were recorded 105, and 188 without systemic connective tissue disease. For 1/640 dilutions the positive predictive value in the connective was 73.3% compared to 26.6% of non-connective, and for values ≥1/1,280 85% versus 15% respectively. When performing the multivariate analysis we observed a positive association between 1/320 dilution OR 3.069 (95% CI: 1.237-7.614; P=.016), 1/640 OR 12.570 (95% CI: 3.659-43.187; P=.000) and ≥1/1,280 OR 42.136 (95% CI: 8.604-206.345; P=.000). These results show association titles dilution ≥1/320 in ANA's first test requested by a Rheumatology Unit with patients with systemic connective tissue disease. The VPP in these patients was higher than previous studies requested by other medical specialties. This may indicate the importance of application of the test in a targeted way. Copyright © 2016 Elsevier España, S.L.U. and Sociedad Española de Reumatología y Colegio Mexicano de Reumatología. All rights reserved.

Optical Coherence Tomography and Autofluorescence Imaging of Human Tonsil

PubMed Central

Pahlevaninezhad, Hamid; Lee, Anthony M. D.; Rosin, Miriam; Sun, Ivan; Zhang, Lewei; Hakimi, Mehrnoush; MacAulay, Calum; Lane, Pierre M.

2014-01-01

For the first time, we present co-registered autofluorescence imaging and optical coherence tomography (AF/OCT) of excised human palatine tonsils to evaluate the capabilities of OCT to visualize tonsil tissue components. Despite limited penetration depth, OCT can provide detailed structural information about tonsil tissue with much higher resolution than that of computed tomography, magnetic resonance imaging, and Ultrasound. Different tonsil tissue components such as epithelium, dense connective tissue, lymphoid nodules, and crypts can be visualized by OCT. The co-registered AF imaging can provide matching biochemical information. AF/OCT scans may provide a non-invasive tool for detecting tonsillar cancers and for studying the natural history of their development. PMID:25542010

Vocal Fold Epithelial Barrier in Health and Injury: A Research Review

ERIC Educational Resources Information Center

Levendoski, Elizabeth Erickson; Leydon, Ciara; Thibeault, Susan L.

2014-01-01

Purpose: Vocal fold epithelium is composed of layers of individual epithelial cells joined by junctional complexes constituting a unique interface with the external environment. This barrier provides structural stability to the vocal folds and protects underlying connective tissue from injury while being nearly continuously exposed to potentially…

Validation of DTI Tractography-Based Measures of Primary Motor Area Connectivity in the Squirrel Monkey Brain

PubMed Central

Gao, Yurui; Choe, Ann S.; Stepniewska, Iwona; Li, Xia; Avison, Malcolm J.; Anderson, Adam W.

2013-01-01

Diffusion tensor imaging (DTI) tractography provides noninvasive measures of structural cortico-cortical connectivity of the brain. However, the agreement between DTI-tractography-based measures and histological ‘ground truth’ has not been quantified. In this study, we reconstructed the 3D density distribution maps (DDM) of fibers labeled with an anatomical tracer, biotinylated dextran amine (BDA), as well as DTI tractography-derived streamlines connecting the primary motor (M1) cortex to other cortical regions in the squirrel monkey brain. We evaluated the agreement in M1-cortical connectivity between the fibers labeled in the brain tissue and DTI streamlines on a regional and voxel-by-voxel basis. We found that DTI tractography is capable of providing inter-regional connectivity comparable to the neuroanatomical connectivity, but is less reliable measuring voxel-to-voxel variations within regions. PMID:24098365

Three-dimensional high-resolution second-harmonic generation imaging of endogenous structural proteins in biological tissues.

PubMed Central

Campagnola, Paul J; Millard, Andrew C; Terasaki, Mark; Hoppe, Pamela E; Malone, Christian J; Mohler, William A

2002-01-01

We find that several key endogenous protein structures give rise to intense second-harmonic generation (SHG)-nonabsorptive frequency doubling of an excitation laser line. Second-harmonic imaging microscopy (SHIM) on a laser-scanning system proves, therefore, to be a powerful and unique tool for high-resolution, high-contrast, three-dimensional studies of live cell and tissue architecture. Unlike fluorescence, SHG suffers no inherent photobleaching or toxicity and does not require exogenous labels. Unlike polarization microscopy, SHIM provides intrinsic confocality and deep sectioning in complex tissues. In this study, we demonstrate the clarity of SHIM optical sectioning within unfixed, unstained thick specimens. SHIM and two-photon excited fluorescence (TPEF) were combined in a dual-mode nonlinear microscopy to elucidate the molecular sources of SHG in live cells and tissues. SHG arose not only from coiled-coil complexes within connective tissues and muscle thick filaments, but also from microtubule arrays within interphase and mitotic cells. Both polarization dependence and a local symmetry cancellation effect of SHG allowed the signal from species generating the second harmonic to be decoded, by ratiometric correlation with TPEF, to yield information on local structure below optical resolution. The physical origin of SHG within these tissues is addressed and is attributed to the laser interaction with dipolar protein structures that is enhanced by the intrinsic chirality of the protein helices. PMID:11751336

Cellular control of connective tissue matrix tension.

PubMed

Langevin, Helene M; Nedergaard, Maiken; Howe, Alan K

2013-08-01

The biomechanical behavior of connective tissue in response to stretching is generally attributed to the molecular composition and organization of its extracellular matrix. It also is becoming apparent that fibroblasts play an active role in regulating connective tissue tension. In response to static stretching of the tissue, fibroblasts expand within minutes by actively remodeling their cytoskeleton. This dynamic change in fibroblast shape contributes to the drop in tissue tension that occurs during viscoelastic relaxation. We propose that this response of fibroblasts plays a role in regulating extracellular fluid flow into the tissue, and protects against swelling when the matrix is stretched. This article reviews the evidence supporting possible mechanisms underlying this response including autocrine purinergic signaling. We also discuss fibroblast regulation of connective tissue tension with respect to lymphatic flow, immune function, and cancer. Copyright © 2013 Wiley Periodicals, Inc.

Functional anatomy of the levator palpebrae superioris muscle and its connective tissue system.

PubMed Central

Ettl, A; Priglinger, S; Kramer, J; Koornneef, L

1996-01-01

AIMS/BACKGROUND: The connective tissue system of the levator palpebrae superioris muscle (LPS) consists of the septa surrounding its muscle sheath, the superior transverse ligament (STL) commonly referred to as 'Whitnall's ligament' and the common sheath which is the fascia between the LPS and the superior rectus muscle (SRM). The anterior band-like component of the common sheath is called transverse superior fascial expansion (TSFE) of the SRM and LPS. It mainly extends from the connective tissue of the trochlea to the fascia of the lacrimal gland. A detailed description of the relation between the LPS and its connective tissue is presented. Furthermore, the course of the LPS in the orbit is described. The study was conducted to provide a morphological basis for biomechanical and clinical considerations regarding ptosis surgery. METHODS: Postmortem dissections were performed in 16 orbits from eight cadavers. The microscopical anatomy was demonstrated in six formalin preserved orbits from six cadavers which had been sectioned in the frontal and sagittal plane and stained with haematoxylin and azophloxin. Surface coil magnetic resonance imaging in the sagittal and coronal plane was performed in five orbits from five normal volunteers using a T1 weighted spin echo sequence. RESULTS: The STL and the TSFE surround the LPS to form a fascial sleeve around the muscle which has attachments to the medial and lateral orbital wall. The TSFE, which is thicker than the STL, blends with Tenon's capsule. The STL and the fascial sheath of the LPS muscle are suspended from the orbital roof by a framework of radial connective tissue septa. MR images show that the TSFE is located between the anterior third of the superior rectus muscle and the segment of the LPS muscle where it changes its course from upwards to downwards. In this area, the LPS reaches its highest point in the orbit (culmination point). The culmination point is located a few millimetres posterior to the equator and superior to the globe. CONCLUSION: Whitnall's ligament can be considered to consist of two distinct parts--the TSFE inferior to the LPS and the STL superior to the LPS. Since the medial and lateral main attachments of Whitnall's ligament are situated inferior to the level of the culmination point of the LPS, the ligament itself is unlikely to suspend the levator muscle. However, a suspension of the LPS may be achieved by the radial connective tissue septa of the superior orbit. The TSFE in connection with the globe may have an additional supporting function. The elasticity of Whitnall's ligament and its connections with highly elastic structures including Tenon's capsule, may provide the morphological substrate for the previously proposed passive (that is, without orbicularis action) lowering of the lid during downward saccades. Images PMID:8949713

Measurement of the Mechanical Properties of Intact Collagen Fibrils

NASA Astrophysics Data System (ADS)

Mercedes, H.; Heim, A.; Matthews, W. G.; Koob, T.

2006-03-01

Motivated by the genetic disorder Ehlers-Danlos syndrome (EDS), in which proper collagen synthesis is interrupted, we are investigating the structural and mechanical properties of collagen fibrils. The fibrous glycoprotein collagen is the most abundant protein found in the human body and plays a key role in the extracellular matrix of the connective tissue, the properties of which are altered in EDS. We have selected as our model system the collagen fibrils of the sea cucumber dermis, a naturally mutable tissue. This system allows us to work with native fibrils which have their proteoglycan complement intact, something that is not possible with reconstituted mammalian collagen fibrils. Using atomic force microscopy, we measure, as a function of the concentration of divalent cations, the fibril diameter, its response to force loading, and the changes in its rigidity. Through these experiments, we will shed light on the mechanisms which control the properties of the sea cucumber dermis and hope to help explain the altered connective tissue extracellular matrix properties associated with EDS.

Alveolar ridge augmentation by connective tissue grafting using a pouch method and modified connective tissue technique: A prospective study

PubMed Central

Agarwal, Ashish; Gupta, Narinder Dev

2015-01-01

Background: Localized alveolar ridge defect may create physiological and pathological problems. Developments in surgical techniques have made it simpler to change the configuration of a ridge to create a more aesthetic and more easily cleansable shape. The purpose of this study was to compare the efficacy of alveolar ridge augmentation using a subepithelial connective tissue graft in pouch and modified connective tissue graft technique. Materials and Methods: In this randomized, double blind, parallel and prospective study, 40 non-smoker individuals with 40 class III alveolar ridge defects in maxillary anterior were randomly divided in two groups. Group I received modified connective tissue graft, while group II were treated with subepithelial connective tissue graft in pouch technique. The defect size was measured in its horizontal and vertical dimension by utilizing a periodontal probe in a stone cast at base line, after 3 months, and 6 months post surgically. Analysis of variance and Bonferroni post-hoc test were used for statistical analysis. A two-tailed P < 0.05 was considered to be statistically significant. Results: Mean values in horizontal width after 6 months were 4.70 ± 0.87 mm, and 4.05 ± 0.89 mm for group I and II, respectively. Regarding vertical heights, obtained mean values were 4.75 ± 0.97 mm and 3.70 ± 0.92 mm for group I and group II, respectively. Conclusion: Within the limitations of this study, connective tissue graft proposed significantly more improvement as compare to connective tissue graft in pouch. PMID:26759591

[Nailfold capillaroscopy in the evaluation of Raynaud's phenomenon and undifferentiated connective tissue disease].

PubMed

Cortes, Sara; Clemente-Coelho, Paulo

2008-01-01

Microvascular abnormalities involved in the pathogenic mechanism of several connective tissue disorders can be detected by nailfold capillaroscopy. Evaluation of the interest of nailfold capillaroscopy results in patients with Raynaud s phenomenon or undifferentiated connective tissue disease and their correlation with diagnostic and therapeutical evolution. Selection of capillaroscopic and laboratory results of patients with the diagnosis of Raynaud s phenomenon (without defined connective tissue disease) or undifferentiated connective tissue disease. Evaluation of the present diagnosis and treatment comparing with the ones existed at the time of capillaroscopy performance. 80 patients were enrolled with an age of 51.4+/-14.3 years (mean+/-SD) 78 females (97.5%) with Raynaud s phenomenon and undifferentiated connective tissue disease 27 patients (33.8%); Raynaud s Phenomenon 46 patients (57.5%); undifferentiated connective tissue disease 7 patients (8.7%). The capillaroscopic results were normal 30 patients (37.5%); minor changes tortuosity enlargement 16 patients (20.0%) major changes 34 patients (42.5%) hemorrhages 25 patients (31.3%) megacapillaries 26 patients (32.5%) avascular areas 3 patients (3.8%). The introduction of new treatments after the capillaroscopy occurred in 32 patients (40.0%) and a new diagnosis was done in 39 patients (48.8%). Major changes in capillaroscopy correlated with the change of diagnosis and the introduction of a new treatment (p<0.0001). Nailfold capillaroscopy performed in patients with isolated Raynaud s phenomenon or undifferentiated connective tissue disease has a role in the prognostic evaluation related to the possibility of an evolution of the diagnosis or to the need of the introduction of new treatments.

Automated segmentation of the lamina cribrosa using Frangi's filter: a novel approach for rapid identification of tissue volume fraction and beam orientation in a trabeculated structure in the eye

PubMed Central

Campbell, Ian C.; Coudrillier, Baptiste; Mensah, Johanne; Abel, Richard L.; Ethier, C. Ross

2015-01-01

The lamina cribrosa (LC) is a tissue in the posterior eye with a complex trabecular microstructure. This tissue is of great research interest, as it is likely the initial site of retinal ganglion cell axonal damage in glaucoma. Unfortunately, the LC is difficult to access experimentally, and thus imaging techniques in tandem with image processing have emerged as powerful tools to study the microstructure and biomechanics of this tissue. Here, we present a staining approach to enhance the contrast of the microstructure in micro-computed tomography (micro-CT) imaging as well as a comparison between tissues imaged with micro-CT and second harmonic generation (SHG) microscopy. We then apply a modified version of Frangi's vesselness filter to automatically segment the connective tissue beams of the LC and determine the orientation of each beam. This approach successfully segmented the beams of a porcine optic nerve head from micro-CT in three dimensions and SHG microscopy in two dimensions. As an application of this filter, we present finite-element modelling of the posterior eye that suggests that connective tissue volume fraction is the major driving factor of LC biomechanics. We conclude that segmentation with Frangi's filter is a powerful tool for future image-driven studies of LC biomechanics. PMID:25589572

Molecular mechanisms of ulcer healing.

PubMed

Tarnawski, A

2000-04-01

An ulcer in the gastrointestinal tract is a deep necrotic lesion penetrating the entire mucosal thickness and muscularis mucosae. Ulcer healing is an active process of filling the mucosal defect with proliferating and migrating epithelial and connective tissue cells. At the ulcer margin, epithelial cells proliferate and migrate onto the granulation tissue to cover (reepithelialize) the ulcer and also invade granulation tissue to reconstruct glandular structures within the ulcer scar. The reepithelialization and reconstruction of glandular structures is controlled by growth factors: trefoil peptides, EGF, HGF, bFGF and PDGF; and locally produced cytokines by regenerating cells in an orderly fashion and integrated manner to ensure the quality of mucosal restoration. These growth factors, most notably EGF, trigger cell proliferation via signal transduction pathways involving EGF-R, adapter proteins (Grb2, Shc and Sos), Ras, Raf1 and MAP (Erk1/Erk2) kinases, which, after translocation to nuclei, activate transcription factors and cell proliferation. Cell migration requires cytoskeletal rearrangements and is controlled by growth factors via Rho/Rac and signaling pathways involving PLC-gamma, PI-3 K and phosphorylation of focal adhesion proteins. Granulation tissue develops at the ulcer base. It consists of connective tissue cells: fibroblasts, macrophages and proliferating endothelial cells forming microvessels under the control of angiogenic growth factors: bFGF, VEGF and angiopoietins, which all promote angiogenesiscapillary vessel formation, essential for the restoration of microvascular network in the mucosa and thus crucial for oxygen and nutrient supply. The major mechanism of activation of angiogenic growth factors and their receptor expression appears to be hypoxia, which activates hypoxia-inducible factor, which binds to VEGF promoter.

Neurovascular manifestations of connective-tissue diseases: A review

PubMed Central

Kim, Sarasa T; Lanzino, Giuseppe; Kallmes, David F

2016-01-01

Patients with connective tissue diseases are thought to be at a higher risk for a number of cerebrovascular diseases such as intracranial aneurysms, dissections, and acute ischemic strokes. In this report, we aim to understand the prevalence and occurrences of such neurovascular manifestations in four heritable connective tissue disorders: Marfan syndrome, Ehlers-Danlos syndrome, Neurofibromatosis Type 1, and Loeys-Dietz syndrome. We discuss the fact that although there are various case studies reporting neurovascular findings in these connective tissue diseases, there is a general lack of case-control and prospective studies investigating the true prevalence of these findings in these patient populations. Furthermore, the differences observed in the manifestations and histology of such disease pathologies encourages future multi-center registries and studies in better characterizing the pathophysiology, prevalence, and ideal treatment options of neurovascular lesions in patents with connective tissue diseases. PMID:27511817

Cone-Beam Computed Tomography Evaluation of Horizontal and Vertical Dimensional Changes in Buccal Peri-Implant Alveolar Bone and Soft Tissue: A 1-Year Prospective Clinical Study.

PubMed

Kaminaka, Akihiro; Nakano, Tamaki; Ono, Shinji; Kato, Tokinori; Yatani, Hirofumi

2015-10-01

This study evaluated changes in the horizontal and vertical dimensions of the buccal alveolar bone and soft tissue over a 1-year period following implant prosthesis. Thirty-three participants with no history of guided bone regeneration or soft tissue augmentation underwent dental implant placement with different types of connections. The dimensions of the buccal alveolar bone and soft tissue were evaluated immediately and at 1 year after prosthesis from reconstructions of cross-sectional cone-beam computed tomography images. The vertical and horizontal loss of buccal bone and soft tissue around implants with conical connections were lower than around those with external or internal connections. Statistically significant negative correlations were observed between initial horizontal bone thickness and changes in vertical bone and soft tissue height (p < .05), and between initial horizontal soft tissue thickness and the change in vertical soft tissue height (p < .05). Implants with a conical connection preserve peri-implant alveolar bone and soft tissue more effectively than other connection types. Furthermore, the initial buccal alveolar bone and soft tissue thickness around the implant platform may influence their vertical dimensional changes at 1 year after implant prosthesis. © 2014 Wiley Periodicals, Inc.

Emission of Biophotons and Adjustable Sounds by the Fascial System: Review and Reflections for Manual Therapy.

PubMed

Bordoni, Bruno; Marelli, Fabiola; Morabito, Bruno; Sacconi, Beatrice

2018-01-01

Every body structure is wrapped in connective tissue or fascia, creating a structural continuity that gives form and function to every tissue and organ. The fascial tissue is uniformly distributed throughout the body, enveloping, interacting with and permeating blood vessels, nerves, viscera, meninges, bones and muscles, creating various layers at different depths and forming a tridimensional metabolic and mechanical matrix. This article reviews the literature on the emission of biophotons and adjustable sounds by the fascial system, because these biological changes could be a means of local and systemic cellular communication and become another assessment tool for manual (therapy) practitioners. This is the first article that discusses these topics in a single text, attempting to bring such information into an area of application that is beneficial to osteopaths, chiropractors, and manual therapists.

Emission of Biophotons and Adjustable Sounds by the Fascial System: Review and Reflections for Manual Therapy

PubMed Central

Marelli, Fabiola; Sacconi, Beatrice

2018-01-01

Every body structure is wrapped in connective tissue or fascia, creating a structural continuity that gives form and function to every tissue and organ. The fascial tissue is uniformly distributed throughout the body, enveloping, interacting with and permeating blood vessels, nerves, viscera, meninges, bones and muscles, creating various layers at different depths and forming a tridimensional metabolic and mechanical matrix. This article reviews the literature on the emission of biophotons and adjustable sounds by the fascial system, because these biological changes could be a means of local and systemic cellular communication and become another assessment tool for manual (therapy) practitioners. This is the first article that discusses these topics in a single text, attempting to bring such information into an area of application that is beneficial to osteopaths, chiropractors, and manual therapists. PMID:29405763

Complex structures from patterned cell sheets

PubMed Central

Misra, M.; Audoly, B.; Shvartsman, S. Y.

2017-01-01

The formation of three-dimensional structures from patterned epithelial sheets plays a key role in tissue morphogenesis. An important class of morphogenetic mechanisms relies on the spatio-temporal control of apical cell contractility, which can result in the localized bending of cell sheets and in-plane cell rearrangements. We have recently proposed a modified vertex model that can be used to systematically explore the connection between the two-dimensional patterns of cell properties and the emerging three-dimensional structures. Here we review the proposed modelling framework and illustrate it through the computational analysis of the vertex model that captures the salient features of the formation of the dorsal appendages during Drosophila oogenesis. This article is part of the themed issue ‘Systems morphodynamics: understanding the development of tissue hardware’. PMID:28348251

Losartan Attenuates Degradation of Aorta and Lung Tissue Micromechanics in a Mouse Model of Severe Marfan Syndrome

PubMed Central

Lee, Jia-Jye; Galatioto, Josephine; Rao, Satish; Ramirez, Francesco; Costa, Kevin D.

2018-01-01

Marfan syndrome (MFS) is an autosomal dominant disease of the connective tissue due to mutations in the fibrillin-1 gene (FBN1). This study aimed at characterizing microelastic properties of the ascending aorta wall and lung parenchyma tissues from wild type (WT) and age-matched Fbn1 hypomorphic mice (Fbn1mgR/mgR mice) to identify tissue-specific biomechanical effects of aging and disease in MFS. Atomic force microscopy (AFM) was used to indent lung parenchyma and aortic wall tissues, using Hybrid Eshelby Decomposition analysis to extract layer-specific properties of the intima and media. The intima stiffened with age and was not different between WT and Fbn1mgR/mgR tissues, whereas the media layer of mutant aortas showed progressive structural and mechanical degradation with a modulus that was 50% softer than WT by 3.5 months of age. Similarly, mutant mice displayed progressive structural and mechanical deterioration of lung tissue, which was over 85% softer than WT by 3.5 months of age. Chronic treatment with the angiotensin type I receptor antagonist, losartan, attenuated the aorta and lung tissue degradation, resulting in structural and mechanical properties not significantly different from age-matched WT controls. By revealing micromechanical softening of elastin-rich aorta and lung tissues with disease progression in fibrillin-1 deficient mice, our findings support the use of losartan as a prophylactic treatment that may abrogate the life-threatening symptoms of MFS. PMID:27090893

Losartan Attenuates Degradation of Aorta and Lung Tissue Micromechanics in a Mouse Model of Severe Marfan Syndrome.

PubMed

Lee, Jia-Jye; Galatioto, Josephine; Rao, Satish; Ramirez, Francesco; Costa, Kevin D

2016-10-01

Marfan syndrome (MFS) is an autosomal dominant disease of the connective tissue due to mutations in the fibrillin-1 gene (FBN1). This study aimed at characterizing microelastic properties of the ascending aortic wall and lung parenchyma tissues from wild type (WT) and age-matched Fbn1 hypomorphic mice (Fbn1(mgR/mgR) mice) to identify tissue-specific biomechanical effects of aging and disease in MFS. Atomic force microscopy was used to indent lung parenchyma and aortic wall tissues, using Hybrid Eshelby Decomposition analysis to extract layer-specific properties of the intima and media. The intima stiffened with age and was not different between WT and Fbn1(mgR/mgR) tissues, whereas the media layer of MFS aortas showed progressive structural and mechanical degradation with a modulus that was 50% softer than WT by 3.5 months of age. Similarly, MFS mice displayed progressive structural and mechanical deterioration of lung tissue, which was over 85% softer than WT by 3.5 months of age. Chronic treatment with the angiotensin type I receptor antagonist, losartan, attenuated the aorta and lung tissue degradation, resulting in structural and mechanical properties not significantly different from age-matched WT controls. By revealing micromechanical softening of elastin-rich aorta and lung tissues with disease progression in fibrillin-1 deficient mice, our findings support the use of losartan as a prophylactic treatment that may abrogate the life-threatening symptoms of MFS.

Comparative morphology of changeable skin papillae in octopus and cuttlefish.

PubMed

Allen, Justine J; Bell, George R R; Kuzirian, Alan M; Velankar, Sachin S; Hanlon, Roger T

2014-04-01

A major component of cephalopod adaptive camouflage behavior has rarely been studied: their ability to change the three-dimensionality of their skin by morphing their malleable dermal papillae. Recent work has established that simple, conical papillae in cuttlefish (Sepia officinalis) function as muscular hydrostats; that is, the muscles that extend a papilla also provide its structural support. We used brightfield and scanning electron microscopy to investigate and compare the functional morphology of nine types of papillae of different shapes, sizes and complexity in six species: S. officinalis small dorsal papillae, Octopus vulgaris small dorsal and ventral eye papillae, Macrotritopus defilippi dorsal eye papillae, Abdopus aculeatus major mantle papillae, O. bimaculoides arm, minor mantle, and dorsal eye papillae, and S. apama face ridge papillae. Most papillae have two sets of muscles responsible for extension: circular dermal erector muscles arranged in a concentric pattern to lift the papilla away from the body surface and horizontal dermal erector muscles to pull the papilla's perimeter toward its core and determine shape. A third set of muscles, retractors, appears to be responsible for pulling a papilla's apex down toward the body surface while stretching out its base. Connective tissue infiltrated with mucopolysaccharides assists with structural support. S. apama face ridge papillae are different: the contraction of erector muscles perpendicular to the ridge causes overlying tissues to buckle. In this case, mucopolysaccharide-rich connective tissue provides structural support. These six species possess changeable papillae that are diverse in size and shape, yet with one exception they share somewhat similar functional morphologies. Future research on papilla morphology, biomechanics and neural control in the many unexamined species of octopus and cuttlefish may uncover new principles of actuation in soft, flexible tissue.

Structural changes in cartilage and collagen studied by high temperature Raman spectroscopy.

PubMed

Fields, Mark; Spencer, Nicholas; Dudhia, Jayesh; McMillan, Paul F

2017-06-01

Understanding the high temperature behavior of collagen and collagenous tissue is important for surgical procedures and biomaterials processing for the food, pharmaceutical, and cosmetics industries. One primary event for proteins is thermal denaturation that involves unfolding the polypeptide chains while maintaining the primary structure intact. Collagen in the extracellular matrix of cartilage and other connective tissue is a hierarchical material containing bundles of triple-helical fibers associated with water and proteoglycan components. Thermal analysis of dehydrated collagen indicates irreversible denaturation at high temperature between 135°C and 200°C, with another reversible event at ∼60-80°C for hydrated samples. We report high temperature Raman spectra for freeze-dried cartilage samples that show an increase in laser-excited fluorescence interpreted as conformational changes associated with denaturation above 140°C. Spectra for separated collagen and proteoglycan fractions extracted from cartilage indicate the changes are associated with collagen. The Raman data also show appearance of new features indicating peptide bond hydrolysis at high temperature implying that molecular H 2 O is retained within the freeze-dried tissue. This is confirmed by thermogravimetric analysis that show 5-7 wt% H 2 O remaining within freeze-dried cartilage that is released progressively upon heating up to 200°C. Spectra obtained after exposure to high temperature and re-hydration following recovery indicate that the capacity of the denatured collagen to re-absorb water is reduced. Our results are important for revealing the presence of bound H 2 O within the collagen component of connective tissue even after freeze-drying and its role in denaturation that is accompanied by or perhaps preceded by breakdown of the primary polypeptide structure. © 2017 Wiley Periodicals, Inc.

The role of extracellular matrix components in pin bone attachments during storage-a comparison between farmed Atlantic salmon (Salmo salar) and cod (Gadus morhua L.).

PubMed

Rønning, Sissel B; Østbye, Tone-Kari; Krasnov, Aleksei; Vuong, Tram T; Veiseth-Kent, Eva; Kolset, Svein O; Pedersen, Mona E

2017-04-01

Pin bones represent a major problem for processing and quality of fish products. Development of methods of removal requires better knowledge of the pin bones' attachment to the muscle and structures involved in the breakdown during loosening. In this study, pin bones from cod and salmon were dissected from fish fillets after slaughter or storage on ice for 5 days, and thereafter analysed with molecular methods, which revealed major differences between these species before and after storage. The connective tissue (CT) attaches the pin bone to the muscle in cod, while the pin bones in salmon are embedded in adipose tissue. Collagens, elastin, lectin-binding proteins and glycosaminoglycans (GAGs) are all components of the attachment site, and this differ between salmon and cod, resulting in a CT in cod that is more resistant to enzymatic degradation compared to the CT in salmon. Structural differences are reflected in the composition of transcriptome. Microarray analysis comparing the attachment sites of the pin bones with a reference muscle sample showed limited differences in salmon. In cod, on the other hand, the variances were substantial, and the gene expression profiles suggested difference in myofibre structure, metabolism and cell processes between the pin bone attachment site and the reference muscle. Degradation of the connective tissue occurs closest to the pin bones and not in the neighbouring tissue, which was shown using light microscopy. This study shows that the attachment of the pin bones in cod and salmon is different; therefore, the development of methods for removal should be tailored to each individual species.

Transient inhibition of connective tissue infiltration and collagen deposition into porous poly(lactic-co-glycolic acid) discs.

PubMed

Love, Ryan J; Jones, Kim S

2013-12-01

Connective tissue rapidly proliferates on and around biomaterials implanted in vivo, which impairs the function of the engineered tissues, biosensors, and devices. Glucocorticoids can be utilized to suppress tissue ingrowth, but can only be used for a limited time because they nonselectively arrest cell proliferation in the local environment. The present study examined use of a prolyl-4-hydroxylase inhibitor, 1,4-dihydrophenonthrolin-4-one-3-carboxylic acid (1,4-DPCA), to suppress connective tissue ingrowth in porous PLGA discs implanted in the peritoneal cavity for 28 days. The prolyl-4-hydroxylase inhibitor was found to be effective at inhibiting collagen deposition within and on the outer surface of the disc, and also limited connective tissue ingrowth, but not to the extent of glucocorticoid inhibition. Finally, it was discovered that 1,4-DPCA suppressed Scavenger Receptor A expression on a macrophage-like cell culture, which may account for the drug's ability to limit connective tissue ingrowth in vivo. Copyright © 2013 Wiley Periodicals, Inc., a Wiley Company.

Immediate placement and provisionalization of maxillary anterior single implant with guided bone regeneration, connective tissue graft, and coronally positioned flap procedures.

PubMed

Waki, Tomonori; Kan, Joseph Y K

2016-01-01

Immediate implant placement and provisionalization in the esthetic zone have been documented with success. The benefit of immediate implant placement and provisionalization is the preservation of papillary mucosa. However, in cases with osseous defects presenting on the facial bony plate, immediate implant placement procedures have resulted in facial gingival recession. Subepithelial connective tissue grafts for immediate implant placement and provisionalization procedures have been reported with a good esthetic outcome. Biotype conversion around implants with subepithelial connective tissue grafts have been advocated, and the resulting tissues appear to be more resistant to recession. The dimensions of peri-implant mucosa in a thick biotype were significantly greater than in a thin biotype. Connective tissue graft with coronally positioned flap procedures on natural teeth has also been documented with success. This article describes a technique combining immediate implant placement, provisionalization, guided bone regeneration (GBR), connective tissue graft, and a coronally positioned flap in order to achieve more stable peri-implant tissue in facial osseous defect situations.

Articular cartilage: from formation to tissue engineering.

PubMed

Camarero-Espinosa, Sandra; Rothen-Rutishauser, Barbara; Foster, E Johan; Weder, Christoph

2016-05-26

Hyaline cartilage is the nonlinear, inhomogeneous, anisotropic, poro-viscoelastic connective tissue that serves as friction-reducing and load-bearing cushion in synovial joints and is vital for mammalian skeletal movements. Due to its avascular nature, low cell density, low proliferative activity and the tendency of chondrocytes to de-differentiate, cartilage cannot regenerate after injury, wear and tear, or degeneration through common diseases such as osteoarthritis. Therefore severe damage usually requires surgical intervention. Current clinical strategies to generate new tissue include debridement, microfracture, autologous chondrocyte transplantation, and mosaicplasty. While articular cartilage was predicted to be one of the first tissues to be successfully engineered, it proved to be challenging to reproduce the complex architecture and biomechanical properties of the native tissue. Despite significant research efforts, only a limited number of studies have evolved up to the clinical trial stage. This review article summarizes the current state of cartilage tissue engineering in the context of relevant biological aspects, such as the formation and growth of hyaline cartilage, its composition, structure and biomechanical properties. Special attention is given to materials development, scaffold designs, fabrication methods, and template-cell interactions, which are of great importance to the structure and functionality of the engineered tissue.

[Involvement of the peripheral nervous system in systemic connective tissue diseases: report on clinical cases].

PubMed

Kujawska-Danecka, Hanna; Masiak, Anna; Smoleńska, Zaneta; Zdrojewski, Zbigniew

2011-01-01

The peripheral nervous system is usually involved in the majority of systemic connective tissue diseases, particularly in systemic lupus erythematosus, Sjögren's syndrome, vasculitis and systemic sclerosis. The pathogenesis of lesions in the peripheral nervous system associated with the autoimmune process is complex and it appears that two mechanisms, immunological and ischemic, are of greatest importance. Structures of the nervous system may be damaged by several autoantibodies (e.g. antineuronal, anti-nerve growth factor, anti-neurotrophins), by cytotoxic effects ofproinflammatory cytokines and by activated cells of the immune system. Local ischemia and hypoxia of neurons caused by inflammation of vasa nervosum represents the second significant mechanism leading to damage of nerve fibres in the peripheral nervous system. We present 3 cases with involvement of the peripheral nervous system as a dominant feature in the clinical picture of systemic connective tissue diseases. Clinical conditions in which the peripheral nervous system is involved include peripheral sensory and sensorimotor polyneuropathy, mononeuropathies, cranial neuropathies, acute inflammatory demyelinating polyneuropathy (Guillian-Barré syndrome), chronic inflammatory demyelinating polyneuropathy, plexopathy, myasthenia gravis, and dysfunctions of the autonomic nervous system. The diagnosis is based on clinical symptoms reported by the patient and disclosed during neurologic examination. The importance of electrophysiologic tests is advocated. Selection of treatment depends on the patient's clinical condition, as well as on the clinical form and type of disease. Treatment relies principally on glucocorticosteroids, intravenous immunoglobulins, cyclophosphamide, and other immunosuppressive drugs. Plasmapheresis and rituximab are administered in severe cases. Rehabilitation of the patient appears to be an important element of therapy. Cases with neurologic symptoms as the first and often the sole manifestation of systemic connective tissue disease are particularly problematic requiring a multidimensional approach; their process of diagnosis and treatment is usually long.

Identifying the architecture of a supracellular actomyosin network that induces tissue folding

NASA Astrophysics Data System (ADS)

Yevick, Hannah; Stoop, Norbert; Dunkel, Jorn; Martin, Adam

During embryonic development, the establishment of correct tissue form ensures proper tissue function. Yet, how the thousands of cells within a tissue coordinate force production to sculpt tissue shape is poorly understood. One important tissue shape change is tissue folding where a cell sheet bends to form a closed tube. Drosophila (fruit fly) embryos undergo such a folding event, called ventral furrow formation. The ventral furrow is associated with a supracellular network of actin and myosin, where actin-myosin fibers assemble and connect between cells. It is not known how this tissue-wide network grows and connects over time, how reproducible it is between embryos, and what determines its architecture. Here, we used topological feature analysis to quantitatively and dynamically map the connections and architecture of this supracellular network across hundreds of cells in the folding tissue. We identified the importance of the cell unit in setting up the tissue-scale architecture of the network. Our mathematical framework allows us to explore stereotypic properties of the myosin network such that we can investigate the reproducibility of mechanical connections for a morphogenetic process. NIH F32.

Evaluation of In Vivo Wound Healing Activity of Bacopa monniera on Different Wound Model in Rats

PubMed Central

Murthy, S.; Gautam, M. K.; Goel, Shalini; Purohit, V.; Sharma, H.; Goel, R. K.

2013-01-01

Wound healing effects of 50% ethanol extract of dried whole plant of Bacopa monniera (BME) was studied on wound models in rats. BME (25 mg/kg) was administered orally, once daily for 10 days (incision and dead space wound models) or for 21 days or more (excision wound model) in rats. BME was studied for its in vitro antimicrobial and in vivo wound breaking strength, WBS (incision model), rate of contraction, period of epithelization, histology of skin (excision model), granulation tissue free radicals (nitric oxide and lipid peroxidation), antioxidants (catalase, superoxide dismutase, and reduced glutathione), acute inflammatory marker (myeloperoxidase), connective tissue markers (hydroxyproline, hexosamine, and hexuronic acid), and deep connective tissue histology (dead space wound). BME showed antimicrobial activity against skin pathogens, enhanced WBS, rate of contraction, skin collagen tissue formation, and early epithelization period with low scar area indicating enhanced healing. Healing effect was further substantiated by decreased free radicals and myeloperoxidase and enhanced antioxidants and connective tissue markers with histological evidence of more collagen formation in skin and deeper connective tissues. BME decreased myeloperoxidase and free radical generated tissue damage, promoting antioxidant status, faster collagen deposition, other connective tissue constituent formation, and antibacterial activity. PMID:23984424

Evaluation of in vivo wound healing activity of Bacopa monniera on different wound model in rats.

PubMed

Murthy, S; Gautam, M K; Goel, Shalini; Purohit, V; Sharma, H; Goel, R K

2013-01-01

Wound healing effects of 50% ethanol extract of dried whole plant of Bacopa monniera (BME) was studied on wound models in rats. BME (25 mg/kg) was administered orally, once daily for 10 days (incision and dead space wound models) or for 21 days or more (excision wound model) in rats. BME was studied for its in vitro antimicrobial and in vivo wound breaking strength, WBS (incision model), rate of contraction, period of epithelization, histology of skin (excision model), granulation tissue free radicals (nitric oxide and lipid peroxidation), antioxidants (catalase, superoxide dismutase, and reduced glutathione), acute inflammatory marker (myeloperoxidase), connective tissue markers (hydroxyproline, hexosamine, and hexuronic acid), and deep connective tissue histology (dead space wound). BME showed antimicrobial activity against skin pathogens, enhanced WBS, rate of contraction, skin collagen tissue formation, and early epithelization period with low scar area indicating enhanced healing. Healing effect was further substantiated by decreased free radicals and myeloperoxidase and enhanced antioxidants and connective tissue markers with histological evidence of more collagen formation in skin and deeper connective tissues. BME decreased myeloperoxidase and free radical generated tissue damage, promoting antioxidant status, faster collagen deposition, other connective tissue constituent formation, and antibacterial activity.

Efficacy of Connective Tissue with and without Periosteum in Regeneration of Intrabony Defects

PubMed Central

Esfahanian, Vahid; Golestaneh, Hedayatollah; Moghaddas, Omid; Ghafari, Mohammad Reza

2014-01-01

Background and aims. Connective tissue grafts with and without periosteum is used in regenerative treatments of bone and has demonstrated successful outcomes in previous investigations. The aim of present study was to evaluate the effectiveness of connective tissue graft with and without periosteum in regeneration of intrabony defects. Materials and methods. In this single-blind randomized split-mouth clinical trial, 15 pairs of intrabony defects in 15 patients with moderate to advanced periodontitis were treated by periosteal connective tissue graft + ABBM (test group) or non-periosteal connective tissue graft + ABBM (control group). Probing pocket depth, clinical attachment level, free gingival margin position, bone crestal position, crest defect depth and defect depth to stent were measured at baseline and after six months by surgical re-entry. Data was analyzed by Student’s t-test and paired t-tests (α=0.05). Results. Changes in clinical parameters after 6 months in the test and control groups were as follows: mean of PPD reduction: 3.1±0.6 (P<0.0001); 2.5±1.0 mm (P<0.0001), CAL gain: 2.3±0.9 (P<0.0001); 2.2±1.0 mm (P<0.0001), bone fill: 2.2±0.7 mm (P<0.0001); 2.2±0.7 mm (P<0.0001), respectively. No significant differences in the position of free gingival margin were observed during 6 months compared to baseline in both groups. Conclusion. Combinations of periosteal connective tissue graft + ABBM and non-periosteal connective tissue graft + ABBM were similarly effective in treating intrabony defects without any favor for any group. Connective tissue and perio-steum can be equally effective in regeneration of intrabony defects. PMID:25587379

Estimating the incidence of connective tissue diseases and vasculitides in a defined population in Northern Savo area in 2010.

PubMed

Elfving, P; Marjoniemi, O; Niinisalo, H; Kononoff, A; Arstila, L; Savolainen, E; Rutanen, J; Kaipiainen-Seppänen, O

2016-07-01

Objective of the study was to evaluate the annual incidence and distribution of autoimmune connective tissue diseases and vasculitides during 2010. All units practicing rheumatology in the Northern Savo area, Finland, participated in the study by collecting data on newly diagnosed adult patients with autoimmune connective tissue disease or vasculitis over 1-year period. Seventy-two cases with autoimmune connective tissue disease were identified. The annual incidence rates were as follows: systemic lupus erythematosus 3.4/100,000 (95 % CI 1.4-7.0), idiopathic inflammatory myopathies 1.9 (0.5-5.0), systemic sclerosis 4.4 (2.0-8.3), mixed connective tissue disease 1.0 (0.1-3.5), Sjögren's syndrome 10.7 (6.7-16.1) and undifferentiated connective tissue disease 13.6 (9.0-19.6). The annual incidence rates among vasculitis category were as follows: antineutrophil cytoplasmic antibody-associated vasculitis 1.5/100,000 (95 % CI 0.3-4.3), central nervous system vasculitis 0.5 (0-2.7) and Henoch-Schönlein purpura 1.5 (0.3-4.3). The annual incidence of giant cell arteritis in the age group of 50 years or older was 7.5/100,000 (95 % CI 3.2-14.8). The longest delay from symptom onset to diagnosis occurred in systemic sclerosis. The incidences of autoimmune connective tissue diseases and vasculitides were comparable with those in published literature. The present study showed female predominance in all connective tissue diseases, excluding idiopathic inflammatory muscle diseases and mean age at onset of disease around 50 years of age. Despite improved diagnostic tools, diagnostic delay is long especially among patients with systemic sclerosis.

Morphology of the lingual papillae in the fishing cat.

PubMed

Emura, Shoichi; Okumura, Toshihiko; Chen, Huayue

2014-01-01

We examined the dorsal lingual surface of an adult fishing cat (Prionailurus viverrinus) by scanning electron microscopy. The filiform papillae on the lingual apex had several pointed processes. The connective tissue core of the filiform papillae resembleda a well in shape. The filiform papillae on the anterior part of the lingual body were large and cylindrical in shape. The connective tissue core of the filiform papillae consisted of a large conical papilla. The filiform papillae on the central part of the lingual body were large and conical. The connective tissue core of the filiform papillae consisted of a large main process and some secondary processes. The connective tissue core of the fungiform papillae did not have processes. The vallate papillae were surrounded by a groove and a pad. The top of the connective tissue core of the vallate papillae had a rough surface with no spines.

Connective Tissue Disorders and Cardiovascular Complications: The indomitable role of Transforming Growth Factor-beta signaling

PubMed Central

Wheeler, Jason B.; Ikonomidis, John S.; Jones, Jeffrey A.

2015-01-01

Marfan Syndrome (MFS) and Loeys-Dietz Syndrome (LDS) represent heritable connective tissue disorders that cosegregate 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. Given the evidence of increased transforming growth factor-beta (TGF-β) signaling in MFS and LDS, this signaling pathway may represent the common link in this relationship. To further explore this hypothetical link, this chapter will review the TGF-β signaling pathway, heritable connective tissue syndromes related to TGF-β receptor (TGFBR) mutations, and discuss the pathogenic contribution of TGF-β to these syndromes with a primary focus on the cardiovascular system. PMID:24443024

NeuroLines: A Subway Map Metaphor for Visualizing Nanoscale Neuronal Connectivity.

PubMed

Al-Awami, Ali K; Beyer, Johanna; Strobelt, Hendrik; Kasthuri, Narayanan; Lichtman, Jeff W; Pfister, Hanspeter; Hadwiger, Markus

2014-12-01

We present NeuroLines, a novel visualization technique designed for scalable detailed analysis of neuronal connectivity at the nanoscale level. The topology of 3D brain tissue data is abstracted into a multi-scale, relative distance-preserving subway map visualization that allows domain scientists to conduct an interactive analysis of neurons and their connectivity. Nanoscale connectomics aims at reverse-engineering the wiring of the brain. Reconstructing and analyzing the detailed connectivity of neurons and neurites (axons, dendrites) will be crucial for understanding the brain and its development and diseases. However, the enormous scale and complexity of nanoscale neuronal connectivity pose big challenges to existing visualization techniques in terms of scalability. NeuroLines offers a scalable visualization framework that can interactively render thousands of neurites, and that supports the detailed analysis of neuronal structures and their connectivity. We describe and analyze the design of NeuroLines based on two real-world use-cases of our collaborators in developmental neuroscience, and investigate its scalability to large-scale neuronal connectivity data.

Advances in bionanomaterials for bone tissue engineering.

PubMed

Scott, Timothy G; Blackburn, Gary; Ashley, Michael; Bayer, Ilker S; Ghosh, Anindya; Biris, Alexandru S; Biswas, Abhijit

2013-01-01

Bone is a specialized form of connective tissue that forms the skeleton of the body and is built at the nano and microscale levels as a multi-component composite material consisting of a hard inorganic phase (minerals) in an elastic, dense organic network. Mimicking bone structure and its properties present an important frontier in the fields of nanotechnology, materials science and bone tissue engineering, given the complex morphology of this tissue. There has been a growing interest in developing artificial bone-mimetic nanomaterials with controllable mineral content, nanostructure, chemistry for bone, cartilage tissue engineering and substitutes. This review describes recent advances in bionanomaterials for bone tissue engineering including developments in soft tissue engineering. The significance and basic process of bone tissue engineering along with different bionanomaterial bone scaffolds made of nanocomposites and nanostructured biopolymers/bioceramics and the prerequisite biomechanical functions are described. It also covers latest developments in soft-tissue reconstruction and replacement. Finally, perspectives on the future direction in nanotechnology-enabled bone tissue engineering are presented.

Persistent supercooling of reproductive shoots is enabled by structural ice barriers being active despite an intact xylem connection

USDA-ARS?s Scientific Manuscript database

Extracellular ice nucleation usually occurs at mild subzero temperatures in most plants. For persistent supercooling of certain plant parts ice barriers are necessary that prevent the entry of ice from otherwise already frozen tissues. The reproductive shoot of the evergreen woody dwarf shrub Callun...

Bio-based polyurethane for tissue engineering applications: How hydroxyapatite nanoparticles influence the structure, thermal and biological behavior of polyurethane composites.

PubMed

Gabriel, Laís P; Santos, Maria Elizabeth M Dos; Jardini, André L; Bastos, Gilmara N T; Dias, Carmen G B T; Webster, Thomas J; Maciel Filho, Rubens

2017-01-01

In this work, thermoset polyurethane composites were prepared by the addition of hydroxyapatite nanoparticles using the reactants polyol polyether and an aliphatic diisocyanate. The polyol employed in this study was extracted from the Euterpe oleracea Mart. seeds from the Amazon Region of Brazil. The influence of hydroxyapatite nanoparticles on the structure and morphology of the composites was studied using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS), the structure was evaluated by Fourier transform infrared spectroscopy (FT-IR), thermal properties were analyzed by thermogravimetry analysis (TGA), and biological properties were studied by in vitro and in vivo studies. It was found that the addition of HA nanoparticles promoted fibroblast adhesion while in vivo investigations with histology confirmed that the composites promoted connective tissue adherence and did not induce inflammation. In this manner, this study supports the further investigation of bio-based, polyurethane/hydroxyapatite composites as biocompatible scaffolds for numerous tissue engineering applications. Copyright © 2016 Elsevier Inc. All rights reserved.

Second harmonic generation microscopy for quantitative analysis of collagen fibrillar structure

PubMed Central

Chen, Xiyi; Nadiarynkh, Oleg; Plotnikov, Sergey; Campagnola, Paul J

2013-01-01

Second-harmonic generation (SHG) microscopy has emerged as a powerful modality for imaging fibrillar collagen in a diverse range of tissues. Because of its underlying physical origin, it is highly sensitive to the collagen fibril/fiber structure, and, importantly, to changes that occur in diseases such as cancer, fibrosis and connective tissue disorders. We discuss how SHG can be used to obtain more structural information on the assembly of collagen in tissues than is possible by other microscopy techniques. We first provide an overview of the state of the art and the physical background of SHG microscopy, and then describe the optical modifications that need to be made to a laser-scanning microscope to enable the measurements. Crucial aspects for biomedical applications are the capabilities and limitations of the different experimental configurations. We estimate that the setup and calibration of the SHG instrument from its component parts will require 2–4 weeks, depending on the level of the user’s experience. PMID:22402635

New lethal disease involving type I and III collagen defect resembling geroderma osteodysplastica, De Barsy syndrome, and Ehlers-Danlos syndrome IV.

PubMed

Jukkola, A; Kauppila, S; Risteli, L; Vuopala, K; Risteli, J; Leisti, J; Pajunen, L

1998-06-01

We describe the clinical findings and biochemical features of a male child suffering from a so far undescribed lethal connective tissue disorder characterised by extreme hypermobility of the joints, lax skin, cataracts, severe growth retardation, and insufficient production of type I and type III procollagens. His features are compared with Ehlers-Danlos type IV, De Barsy syndrome, and geroderma osteodysplastica, as these disorders show some symptoms and signs shared with our patient. The child died because of failure of the connective tissue structures joining the skull and the spine, leading to progressive spinal stenosis. The aortic valve was translucent and insufficient. The clinical symptoms and signs, together with histological findings, suggested a collagen defect. Studies on both skin fibroblast cultures and the patient's serum showed reduced synthesis of collagen types I and III at the protein and RNA levels. The sizes of the mRNAs and newly synthesised proteins were normal, excluding gross structural abnormalities. These findings are not in accordance with any other collagen defect characterised so far.

Discriminating the Difference between Remote and Close Association with Relation to White-Matter Structural Connectivity

PubMed Central

Wu, Chinglin; Zhong, Suyu; Chen, Hsuehchih

2016-01-01

Remote association is a core ability that influences creative output. In contrast to close association, remote association is commonly agreed to be connected with more original and unique concepts. However, although existing studies have discovered that creativity is closely related to the white-matter structure of the brain, there are no studies that examine the relevance between the connectivity efficiencies and creativity of the brain regions from the perspective of networks. Consequently, this study constructed a brain white matter network structure that consisted of cerebral tissues and nerve fibers and used graph theory to analyze the connection efficiencies among the network nodes, further illuminating the differences between remote and close association in relation to the connectivity of the brain network. Researchers analyzed correlations between the scores of 35 healthy adults with regard to remote and close associations and the connectivity efficiencies of the white-matter network of the brain. Controlling for gender, age, and verbal intelligence, the remote association positively correlated with the global efficiency and negatively correlated with the levels of small-world. A close association negatively correlated with the global efficiency. Notably, the node efficiency in the middle temporal gyrus (MTG) positively correlated with remote association and negatively correlated with close association. To summarize, remote and close associations work differently as patterns in the brain network. Remote association requires efficient and convenient mutual connections between different brain regions, while close association emphasizes the limited connections that exist in a local region. These results are consistent with previous results, which indicate that creativity is based on the efficient integration and connection between different regions of the brain and that temporal lobes are the key regions for discriminating remote and close associations. PMID:27760177

[CLINICAL CHARACTERISTICS OF CONGENITAL HEART DISEASES ASSOCIATED WITH CONNECTIVE TISSUE DISPLASIA AT CHILDREN LIVING IN EAST REGION OF KAZAKHSTAN].

PubMed

Madiyeva, M; Rymbayeva, T

2017-11-01

The frequency of the combination of congenital heart defects (CHD) and connective tissue dysplasia remains poorly understood. And connective tissue dysplasia enhance severity the clinical of CHD. The aim of the study was to conduct a clinical and laboratory analysis of combinations of congenital heart defects and connective tissue dysplasia in children of Semey and to determine the risk for the development of these pathologies. The object of the study is the children of Semey (East Kazakhstan) aged 1-14 with congenital heart defects (CHD), with connective tissue dysplasia, healthy children and their mothers. Definition complex clinical and laboratory studies in children with CHD and connective tissue dysplasia, and their mothers. In children with CHD, the frequency of external and visceral signs of dysplasia was high. In 88.1% of cases in children with CHD was diagnosed 2-3 degrees of dysplasia. Was found difference in the microelement composition of blood serum and of hemostasis in children with CHD were expressed by hypofibrinogenemia, hypocalcemia, hypomagnesemia. Excess of the frequency of signs of dysplasia in mothers over the control group to consider dysplasia as a factor that influences the clinical of CHD.

Remodeling of the Connective Tissue Microarchitecture of the Lamina Cribrosa in Early Experimental Glaucoma

PubMed Central

Roberts, Michael D.; Grau, Vicente; Grimm, Jonathan; Reynaud, Juan; Bellezza, Anthony J.; Burgoyne, Claude F.; Downs, J. Crawford

2009-01-01

Purpose To characterize the trabeculated connective tissue microarchitecture of the lamina cribrosa (LC) in terms of total connective tissue volume (CTV), connective tissue volume fraction (CTVF), predominant beam orientation, and material anisotropy in monkeys with early experimental glaucoma (EG). Methods The optic nerve heads from three monkeys with unilateral EG and four bilaterally normal monkeys were three dimensionally reconstructed from tissues perfusion fixed at an intraocular pressure of 10 mm Hg. A three-dimensional segmentation algorithm was used to extract a binary, voxel-based representation of the porous LC connective tissue microstructure that was regionalized into 45 subvolumes, and the following quantities were calculated: total CTV within the LC, mean and regional CTVF, regional predominant beam orientation, and mean and regional material anisotropy. Results Regional variation within the laminar microstructure was considerable within the normal eyes of all monkeys. The laminar connective tissue was generally most dense in the central and superior regions for the paired normal eyes, and laminar beams were radially oriented at the periphery for all eyes considered. CTV increased substantially in EG eyes compared with contralateral normal eyes (82%, 44%, 45% increases; P < 0.05), but average CTVF changed little (−7%, 1%, and −2% in the EG eyes). There were more laminar beams through the thickness of the LC in the EG eyes than in the normal controls (46%, 18%, 17% increases). Conclusions The substantial increase in laminar CTV with little change in CTVF suggests that significant alterations in connective and nonconnective tissue components in the laminar region occur in the early stages of glaucomatous damage. PMID:18806292

[Stomach cancer in patients with systemic non-differentiated connective tissue dysplasia].

PubMed

Zil'ber, V S

2014-01-01

The study was designed as a comparative analysis of clinical and anamnestic data and results of morphological studies of surgically obtained tissues from 61 patients with stomach cancer (SC) aged 29-78 yr with (group 1) and without (group 2) signs of connective tissue dysplasia (CTD). The groups had an identical structure of SC hystological types, but in group 1 the tumours were localized mainly in the stomach body (60.6%, p < 0.05) and in group 2 in the cardia (32.1%, p < 0.05). In group 1, SC was more frequently associated with chronic (sometimes multiple) ulcers outside the tumor (18.2 compared with 7.1% in group 2). Comparative analysis revealed the following features of SC in patients with CTD: predominance of stigmatization signs in the urogenital system (57.6%) and gastrointestinal tract (42.4%), cyst formation in different organs (75.8%) especially in kidneys (48.5%), high frequency of gastric problems in medical history (chronic gastritis, ulcer disease) (72.7 and 35.7% in groups 1 and 2 respectively, p < 0.05) and concomitant pathology of urogenital system (42.4%, p < 0.05). These peculiarities may be used as the marker for the inclusion of patients in the risk group for SC. Taking into account plastic, morphogenetic, and protective functions of connective tissue under physiological conditions, the above epithelial-stromal relationships and peculiarities of reparative processes in gastric mucosa one can not exclude effect of CTD on gastric cancerogenesis. This implies the necessity of further studies.

Connective Tissue Characteristics around Healing Abutments of Different Geometries: New Methodological Technique under Circularly Polarized Light.

PubMed

Delgado-Ruiz, Rafael Arcesio; Calvo-Guirado, Jose Luis; Abboud, Marcus; Ramirez-Fernandez, Maria Piedad; Maté-Sánchez de Val, José Eduardo; Negri, Bruno; Gomez-Moreno, Gerardo; Markovic, Aleksa

2015-08-01

To describe contact, thickness, density, and orientation of connective tissue fibers around healing abutments of different geometries by means of a new method using coordinates. Following the bilateral extraction of mandibular premolars (P2, P3, and P4) from six fox hound dogs and a 2-month healing period, 36 titanium implants were inserted, onto which two groups of healing abutments of different geometry were screwed: Group A (concave abutments) and Group B (wider healing abutment). After 3 months the animals were sacrificed and samples extracted containing each implant and surrounding soft and hard tissues. Histological analysis was performed without decalcifying the samples by means of circularly polarized light under optical microscope and a system of vertical and horizontal coordinates across all the connective tissue in an area delimited by the implant/abutment, epithelium, and bone tissue. In no case had the connective tissue formed a connection to the healing abutment/implant in the internal zone; a space of 35 ± 10 μm separated the connective tissue fibers from the healing abutment surface. The total thickness of connective tissue in the horizontal direction was significantly greater in the medial zone in Group B than in Group A (p < .05). The orientation of the fibers varied according to the coordinate area so that internal coordinates showed a higher percentage of parallel fibers in Group A (p < .05) and a higher percentage of oblique fibers in Group B (p < .05); medial coordinates showed more oblique fibers (p < .05); and the area of external coordinates showed the highest percentage of perpendicular fibers (p < .05). The fiber density was higher in the basal and medial areas (p < .05). Abutment geometry influences the orientation of collagen fibers; therefore, an abutment with a profile wider than the implant platform favors oblique and perpendicular orientation of collagen fibers and greater connective tissue thickness. © 2013 Wiley Periodicals, Inc.

[50 years of connective tissue research: from the French Connective Tissue Club to the French Society of Extracellular Matrix Biology].

PubMed

Maquart, François-Xavier; Borel, Jacques-Paul

2012-01-01

The history of connective tissue research began in the late 18th century. However, it is only 50 years later that the concept of connective tissue was shaped. It took another fifty years before biochemical knowledge of extracellular matrix macromolecules began to emerge in the first half of the 20th century. In 1962, thanks to Ladislas and Barbara Robert, back from the US, the first society called "French Connective Tissue Club" was created in Paris. The first board was constituted of Albert Delaunay, Suzanne Bazin and Ladislas Robert. Very quickly, under the influence of these pioneers, national and international meetings were organized and, in 1967, a "Federation of the European Connective Tissue Clubs" was created at the initiative of Ladislas Robert (Paris) and John Scott (Manchester). It spread rapidly to the major European nations. In 1982 the transformation of "Clubs" in "Societies" occurred, a name more in line with the requirements of the time. In 2008, the "French Connective Tissue Society" became the "French Society of Extracellular Matrix Biology" ("Société Française de Biologie de la Matrice Extracellulaire", SFBMEc), to better highlight the importance of the extracellular matrix in the biology of living organisms. The SFBMEc's mission today is to promote and develop scientific exchanges between academic, industrial, and hospital laboratories involved in research on the extracellular matrix. SFBMEc organizes or subsidizes scientific meetings and awards scholarships to Ph.D. students or post-docs to participate in international conferences. It includes 200 to 250 members from different disciplines, developing strong interactions between scientists, clinicians and pathologists. It is present all around the French territory in many research laboratories. During these last 50 years, the extraordinary advances made possible by the development of new investigation techniques, in particular molecular biology, cell and tissue imaging, molecular modeling, etc., have permitted a considerable increase of the knowledge in the field of connective tissue. © Société de Biologie, 2012.

Transcriptome analysis of skin fibroblasts with dominant negative COL3A1 mutations provides molecular insights into the etiopathology of vascular Ehlers-Danlos syndrome

PubMed Central

Chiarelli, Nicola; Carini, Giulia; Zoppi, Nicoletta; Ritelli, Marco

2018-01-01

Vascular Ehlers-Danlos syndrome (vEDS) is a dominantly inherited connective tissue disorder caused by mutations in the COL3A1 gene that encodes type III collagen (COLLIII), which is the major expressed collagen in blood vessels and hollow organs. The majority of disease-causing variants in COL3A1 are glycine substitutions and in-frame splice mutations in the triple helix domain that through a dominant negative effect are associated with the severe clinical spectrum potentially lethal of vEDS, characterized by fragility of soft connective tissues with arterial and organ ruptures. To shed lights into molecular mechanisms underlying vEDS, we performed gene expression profiling in cultured skin fibroblasts from three patients with different structural COL3A1 mutations. Transcriptome analysis revealed significant changes in the expression levels of several genes involved in maintenance of cell redox and endoplasmic reticulum (ER) homeostasis, COLLs folding and extracellular matrix (ECM) organization, formation of the proteasome complex, and cell cycle regulation. Protein analyses showed that aberrant COLLIII expression is associated with the disassembly of many structural ECM constituents, such as fibrillins, EMILINs, and elastin, as well as with the reduction of the proteoglycans perlecan, decorin, and versican, all playing an important role in the vascular system. Furthermore, the altered distribution of the ER marker protein disulfide isomerase PDI and the strong reduction of the COLLs-modifying enzyme FKBP22 are consistent with the disturbance of ER-related homeostasis and COLLs biosynthesis and post-translational modifications, indicated by microarray analysis. Our findings add new insights into the pathophysiology of this severe vascular disorder, since they provide a picture of the gene expression changes in vEDS skin fibroblasts and highlight that dominant negative mutations in COL3A1 also affect post-translational modifications and deposition into the ECM of several structural proteins crucial to the integrity of soft connective tissues. PMID:29346445

Transcriptome analysis of skin fibroblasts with dominant negative COL3A1 mutations provides molecular insights into the etiopathology of vascular Ehlers-Danlos syndrome.

PubMed

Chiarelli, Nicola; Carini, Giulia; Zoppi, Nicoletta; Ritelli, Marco; Colombi, Marina

2018-01-01

Vascular Ehlers-Danlos syndrome (vEDS) is a dominantly inherited connective tissue disorder caused by mutations in the COL3A1 gene that encodes type III collagen (COLLIII), which is the major expressed collagen in blood vessels and hollow organs. The majority of disease-causing variants in COL3A1 are glycine substitutions and in-frame splice mutations in the triple helix domain that through a dominant negative effect are associated with the severe clinical spectrum potentially lethal of vEDS, characterized by fragility of soft connective tissues with arterial and organ ruptures. To shed lights into molecular mechanisms underlying vEDS, we performed gene expression profiling in cultured skin fibroblasts from three patients with different structural COL3A1 mutations. Transcriptome analysis revealed significant changes in the expression levels of several genes involved in maintenance of cell redox and endoplasmic reticulum (ER) homeostasis, COLLs folding and extracellular matrix (ECM) organization, formation of the proteasome complex, and cell cycle regulation. Protein analyses showed that aberrant COLLIII expression is associated with the disassembly of many structural ECM constituents, such as fibrillins, EMILINs, and elastin, as well as with the reduction of the proteoglycans perlecan, decorin, and versican, all playing an important role in the vascular system. Furthermore, the altered distribution of the ER marker protein disulfide isomerase PDI and the strong reduction of the COLLs-modifying enzyme FKBP22 are consistent with the disturbance of ER-related homeostasis and COLLs biosynthesis and post-translational modifications, indicated by microarray analysis. Our findings add new insights into the pathophysiology of this severe vascular disorder, since they provide a picture of the gene expression changes in vEDS skin fibroblasts and highlight that dominant negative mutations in COL3A1 also affect post-translational modifications and deposition into the ECM of several structural proteins crucial to the integrity of soft connective tissues.

Functional Morphology of the Arm Spine Joint and Adjacent Structures of the Brittlestar Ophiocomina nigra (Echinodermata: Ophiuroidea)

PubMed Central

Wilkie, Iain C.

2016-01-01

The skeletal morphology of the arm spine joint of the brittlestar Ophiocomina nigra was examined by scanning electron microscopy and the associated epidermis, connective tissue structures, juxtaligamental system and muscle by optical and transmission electron microscopy. The behaviour of spines in living animals was observed and two experiments were conducted to establish if the spine ligament is mutable collagenous tissue: these determined (1) if animals could detach spines to which plastic tags had been attached and (2) if the extension under constant load of isolated joint preparations was affected by high potassium stimulation. The articulation normally operates as a flexible joint in which the articular surfaces are separated by compliant connective tissue. The articular surfaces comprise a reniform apposition and peg-in-socket mechanical stop, and function primarily to stabilise spines in the erect position. Erect spines can be completely immobilised, which depends on the ligament having mutable tensile properties, as was inferred from the ability of animals to detach tagged spines and the responsiveness of isolated joint preparations to high potassium. The epidermis surrounding the joint has circumferential constrictions that facilitate compression folding and unfolding when the spine is inclined. The interarticular connective tissue is an acellular meshwork of collagen fibril bundles and may serve to reduce frictional forces between the articular surfaces. The ligament consists of parallel bundles of collagen fibrils and 7–14 nm microfibrils. Its passive elastic recoil contributes to the re-erection of inclined spines. The ligament is permeated by cell processes containing large dense-core vesicles, which belong to two types of juxtaligamental cells, one of which is probably peptidergic. The spine muscle consists of obliquely striated myocytes that are linked to the skeleton by extensions of their basement membranes. Muscle contraction may serve mainly to complete the process of spine erection by ensuring close contact between the articular surfaces. PMID:27974856

STRETCHING IMPACTS INFLAMMATION RESOLUTION IN CONNECTIVE TISSUE

PubMed Central

Berrueta, Lisbeth; Muskaj, Igla; Olenich, Sara; Butler, Taylor; Badger, Gary J.; Colas, Romain A.; Spite, Matthew; Serhan, Charles N.; Langevin, Helene M.

2016-01-01

Acute inflammation is accompanied from its outset by the release of specialized pro-resolving mediators (SPMs), including resolvins, that orchestrate the resolution of local inflammation. We showed earlier that, in rats with subcutaneous inflammation of the back induced by carrageenan, stretching for 10 minutes twice daily reduced inflammation and improved pain, two weeks after carrageenan injection. In this study, we hypothesized that stretching of connective tissue activates local pro-resolving mechanisms within the tissue in the acute phase of inflammation. In rats injected with carrageenan and randomized to stretch vs. no stretch for 48 hours, stretching reduced inflammatory lesion thickness and neutrophil count, and increased resolvin (RvD1) concentrations within lesions. Furthermore, subcutaneous resolvin injection mimicked the effect of stretching. In ex vivo experiments, stretching of connective tissue reduced the migration of neutrophils and increased tissue RvD1 concentration. These results demonstrate a direct mechanical impact of stretching on inflammation-regulation mechanisms within connective tissue. PMID:26588184

Neuroanatomic connectivity of the human ascending arousal system critical to consciousness and its disorders.

PubMed

Edlow, Brian L; Takahashi, Emi; Wu, Ona; Benner, Thomas; Dai, Guangping; Bu, Lihong; Grant, Patricia Ellen; Greer, David M; Greenberg, Steven M; Kinney, Hannah C; Folkerth, Rebecca D

2012-06-01

The ascending reticular activating system (ARAS) mediates arousal, an essential component of human consciousness. Lesions of the ARAS cause coma, the most severe disorder of consciousness. Because of current methodological limitations, including of postmortem tissue analysis, the neuroanatomic connectivity of the human ARAS is poorly understood. We applied the advanced imaging technique of high angular resolution diffusion imaging (HARDI) to elucidate the structural connectivity of the ARAS in 3 adult human brains, 2 of which were imaged postmortem. High angular resolution diffusion imaging tractography identified the ARAS connectivity previously described in animals and also revealed novel human pathways connecting the brainstem to the thalamus, the hypothalamus, and the basal forebrain. Each pathway contained different distributions of fiber tracts from known neurotransmitter-specific ARAS nuclei in the brainstem. The histologically guided tractography findings reported here provide initial evidence for human-specific pathways of the ARAS. The unique composition of neurotransmitter-specific fiber tracts within each ARAS pathway suggests structural specializations that subserve the different functional characteristics of human arousal. This ARAS connectivity analysis provides proof of principle that HARDI tractography may affect the study of human consciousness and its disorders, including in neuropathologic studies of patients dying in coma and the persistent vegetative state.

WE-DE-202-01: Connecting Nanoscale Physics to Initial DNA Damage Through Track Structure Simulations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schuemann, J.

Radiation therapy for the treatment of cancer has been established as a highly precise and effective way to eradicate a localized region of diseased tissue. To achieve further significant gains in the therapeutic ratio, we need to move towards biologically optimized treatment planning. To achieve this goal, we need to understand how the radiation-type dependent patterns of induced energy depositions within the cell (physics) connect via molecular, cellular and tissue reactions to treatment outcome such as tumor control and undesirable effects on normal tissue. Several computational biology approaches have been developed connecting physics to biology. Monte Carlo simulations are themore » most accurate method to calculate physical dose distributions at the nanometer scale, however simulations at the DNA scale are slow and repair processes are generally not simulated. Alternative models that rely on the random formation of individual DNA lesions within one or two turns of the DNA have been shown to reproduce the clusters of DNA lesions, including single strand breaks (SSBs), double strand breaks (DSBs) without the need for detailed track structure simulations. Efficient computational simulations of initial DNA damage induction facilitate computational modeling of DNA repair and other molecular and cellular processes. Mechanistic, multiscale models provide a useful conceptual framework to test biological hypotheses and help connect fundamental information about track structure and dosimetry at the sub-cellular level to dose-response effects on larger scales. In this symposium we will learn about the current state of the art of computational approaches estimating radiation damage at the cellular and sub-cellular scale. How can understanding the physics interactions at the DNA level be used to predict biological outcome? We will discuss if and how such calculations are relevant to advance our understanding of radiation damage and its repair, or, if the underlying biological processes are too complex for a mechanistic approach. Can computer simulations be used to guide future biological research? We will debate the feasibility of explaining biology from a physicists’ perspective. Learning Objectives: Understand the potential applications and limitations of computational methods for dose-response modeling at the molecular, cellular and tissue levels Learn about mechanism of action underlying the induction, repair and biological processing of damage to DNA and other constituents Understand how effects and processes at one biological scale impact on biological processes and outcomes on other scales J. Schuemann, NCI/NIH grantsS. McMahon, Funding: European Commission FP7 (grant EC FP7 MC-IOF-623630)« less

Col-F, a fluorescent probe for ex vivo confocal imaging of collagen and elastin in animal tissues.

PubMed

Biela, Ewa; Galas, Jerzy; Lee, Brian; Johnson, Gary L; Darzynkiewicz, Zbigniew; Dobrucki, Jurek W

2013-06-01

A new low-molecular-weight fluorescent probe, Col-F, that exhibits affinity to collagen and elastin, was used successfully in imaging of extracellular matrix in freshly excised animal tissues. Col-F readily penetrates between live cells into tissues and binds to fibers of collagen and elastin by a noncovalent mechanism. Fibers of collagen and elastin have been stained in a variety of tissues, including tendon, skeletal muscle, connective tissue, and arteries. Cells migrating in a Col-F-stained collagenous biomaterial were also imaged. No phototoxic effects were detected when live keratocytes were imaged in the in vitro culture in the presence of Col-F. In conclusion, Col-F provides a simple and convenient tool for fluorescence three-dimensional imaging of intricate collagenous and elastic structures in live and fixed animal tissues, as well as in collagen-containing biomaterials. Copyright © 2013 International Society for Advancement of Cytometry.

Quantitative morphology in canine cutaneous soft tissue sarcomas.

PubMed

Simeonov, R; Ananiev, J; Gulubova, M

2015-12-01

Stained cytological specimens from 24 dogs with spontaneous soft tissue sarcomas [fibrosarcoma (n = 8), liposarcoma (n = 8) and haemangiopericytoma (n = 8)], and 24 dogs with reactive connective tissue lesions [granulation tissue (n = 12) and dermal fibrosis (n = 12)] were analysed by computer-assisted nuclear morphometry. The studied morphometric parameters were: mean nuclear area (MNA; µm(2)), mean nuclear perimeter (MNP; µm), mean nuclear diameter (MND mean; µm), minimum nuclear diameter (Dmin; µm) and maximum nuclear diameter (Dmax; µm). The study aimed to evaluate (1) possibility for quantitative differentiation of soft tissue sarcomas from reactive connective tissue lesions and (2) by using cytomorphometry, to differentiate the various histopathological soft tissue sarcomas subtypes in dogs. The mean values of all nuclear cytomorphometric parameters (except for Dmax) were statistically significantly higher in reactive connective tissue processes than in soft tissue sarcomas. At the same time, however, there were no considerable differences among the different sarcoma subtypes. The results demonstrated that the quantitative differentiation of reactive connective tissue processes from soft tissue sarcomas in dogs is possible, but the same was not true for the different canine soft tissue sarcoma subtypes. Further investigations on this topic are necessary for thorough explication of the role of quantitative morphology in the diagnostics of mesenchymal neoplasms and tumour-like fibrous lesions in dogs. © 2014 John Wiley & Sons Ltd.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jorgens, Danielle M.; Inman, Jamie L.; Wojcik, Michal

The importance of context in regulation of gene expression is now an accepted principle; yet the mechanism by which the microenvironment communicates with the nucleus and chromatin in healthy tissues is poorly understood. A functional role for nuclear and cytoskeletal architecture is suggested by the phenotypic differences observed between epithelial and mesenchymal cells. Capitalizing on recent advances in cryogenic techniques, volume electron microscopy and super-resolution light microscopy, we studied human mammary epithelial cells in three-dimensional (3D) cultures forming growtharrested acini. Intriguingly, we found deep nuclear invaginations and tunnels traversing the nucleus, encasing cytoskeletal actin and/or intermediate filaments, which connect tomore » the outer nuclear envelope. Also, the cytoskeleton is connected both to other cells through desmosome adhesion complexes and to the extracellular matrix through hemidesmosomes. This finding supports a physical and/or mechanical link from the desmosomes and hemidesmosomes to the nucleus, which had previously been hypothesized but now is visualized for the first time. These unique structures, including the nuclear invaginations and the cytoskeletal connectivity to the cell nucleus, are consistent with a dynamic reciprocity between the nucleus and the outside of epithelial cells and tissues.« less

Alveolar Ridge Contouring with Free Connective Tissue Graft at Implant Placement: A 5-Year Consecutive Clinical Study.

PubMed

Hanser, Thomas; Khoury, Fouad

2016-01-01

This study evaluated volume stability after alveolar ridge contouring with free connective tissue grafts at implant placement in single-tooth gaps. A total of 52 single-tooth gaps with labial volume deficiencies in the maxilla (incisors, canines, and premolars) were consecutively treated with implants and concomitant free palatal connective tissue grafts in 46 patients between 2006 and 2009. Implants had to be covered with at least 2 mm peri-implant local bone after insertion. At implant placement, a free connective tissue graft from the palate was fixed inside a labial split-thickness flap to form an existing concave buccal alveolar ridge contour due to tissue volume deficiency into a convex shape. Standardized volumetric measurements of the labial alveolar contour using a template were evaluated before connective tissue grafting and at 2 weeks, 1 year, and 5 years after implantprosthetic incorporation. Tissue volume had increased significantly (P < .05) in all six reference points representing the outer alveolar soft tissue contour of the implant before connective tissue grafting to baseline (2 weeks after implant-prosthetic incorporation). Statistically, 50% of the reference points (P > .05) kept their volume from baseline to 1 year after prosthetic incorporation and from baseline to 5 years after prosthetic incorporation, respectively, whereas reference points located within the area of the implant sulcus showed a significant (P < .05) decrease in volume. Clinically, 5 years after prosthetic incorporation the originally concave buccal alveolar contour was still convex in all implants, leading to a continuous favorable anatomical shape and improved esthetic situation. Intraoral radiographs confirmed osseointegration and stable peri-implant parameters with a survival rate of 100% after a follow-up of approximately 5 years. Implant placement with concomitant free connective tissue grafting appears to be an appropriate long-term means to contour preexisting buccal alveolar volume deficiencies in single implants.

Fixture-abutment connection surface and micro-gap measurements by 3D micro-tomographic technique analysis.

PubMed

Meleo, Deborah; Baggi, Luigi; Di Girolamo, Michele; Di Carlo, Fabio; Pecci, Raffaella; Bedini, Rossella

2012-01-01

X-ray micro-tomography (micro-CT) is a miniaturized form of conventional computed axial tomography (CAT) able to investigate small radio-opaque objects at a-few-microns high resolution, in a non-destructive, non-invasive, and tri-dimensional way. Compared to traditional optical and electron microscopy techniques, which provide two-dimensional images, this innovative investigation technology enables a sample tri-dimensional analysis without cutting, coating or exposing the object to any particular chemical treatment. X-ray micro-tomography matches ideal 3D microscopy features: the possibility of investigating an object in natural conditions and without any preparation or alteration; non-invasive, non-destructive, and sufficiently magnified 3D reconstruction; reliable measurement of numeric data of the internal structure (morphology, structure and ultra-structure). Hence, this technique has multi-fold applications in a wide range of fields, not only in medical and odontostomatologic areas, but also in biomedical engineering, materials science, biology, electronics, geology, archaeology, oil industry, and semi-conductors industry. This study shows possible applications of micro-CT in dental implantology to analyze 3D micro-features of dental implant to abutment interface. Indeed, implant-abutment misfit is known to increase mechanical stress on connection structures and surrounding bone tissue. This condition may cause not only screw preload loss or screw fracture, but also biological issues in peri-implant tissues.

Expression of connective tissue growth factor is a prognostic marker for patients with intrahepatic cholangiocarcinoma.

PubMed

Gardini, A; Corti, B; Fiorentino, M; Altimari, A; Ercolani, G; Grazi, G L; Pinna, A D; Grigioni, W F; D'Errico Grigioni, A

2005-04-01

Connective tissue growth factor is a member of the 'CCN' protein family. Consistent with its profibrotic properties, it is over-expressed in several human epithelial malignancies. We have retrospectively evaluated by immunohistochemistry the presence of connective tissue growth factor in archival tissues from 55 resected intrahepatic cholangiocarcinomas and compared its expression to the main pathological parameters, disease free and overall survival. Tumours were scored as high and low/absent expressers (> or =50%, 0-50% cells, respectively). Thirty-three of 55 cholangiocarcinomas (60%) were high and 22 (40%) low expressers. No significant correlation was found between connective tissue growth factor and tumour grade, tumour location, vascular and perineural invasion. Eighteen of 22 (82%) low/absent expressers and 12/33 (36%) high expressers had recurrence of disease (P=0.001). Low/absent expressers showed a poor disease free and overall survival compared with the higher expressers (P<0.001). Vascular invasion was related to tumour recurrence (P=0.025) and to decreased disease free survival (P<0.05). During proportional hazard regression analysis, only connective tissue growth factor was found to influence disease free survival (P=0.01). Expression of connective tissue growth factor is an independent prognostic indicator of both tumour recurrence and overall survival for intrahepatic cholangiocarcinoma patients regardless of tumour location, tumour grade, vascular and perineural invasion.

Selective laser melting of titanium alloy enables osseointegration of porous multi-rooted implants in a rabbit model.

PubMed

Peng, Wei; Xu, Liangwei; You, Jia; Fang, Lihua; Zhang, Qing

2016-07-21

Osseointegration refers to the direct connection between living bone and the surface of a load-bearing artificial implant. Porous implants with well-controlled porosity and pore size can enhance osseointegration. However, until recently implants were produced by machining solid core titanium rods. The aim of this study was to develop a multi-rooted dental implant (MRI) with a connected porous surface structure to facilitate osseointegration. MRIs manufactured by selective laser melting (SLM) and commercial implants with resorbable blasting media (RBM)-treated surfaces were inserted into the hind limbs of New Zealand white rabbits. Osseointegration was evaluated periodically over 12 weeks by micro-computerized tomography (CT) scanning, histological analysis, mechanical push-out tests, and torque tests. Bone volume densities were consistently higher in the MRI group than in the RBM group throughout the study period, ultimately resulting in a peak value of 48.41 % for the MRI group. Histological analysis revealed denser surrounding bone growth in the MRIs; after 4 and 8 weeks, bone tissue had grown into the pore structures and root bifurcation areas, respectively. Biomechanics tests indicated binding of the porous MRIs to the neobone tissues, as push-out forces strengthened from 294.7 to 446.5 N and maximum mean torque forces improved from 81.15 to 289.57 N (MRI), versus 34.79 to 87.8 N in the RBM group. MRIs manufactured by SLM possess a connected porous surface structure that improves the osteogenic characteristics of the implant surface.

Genetic diversity and connectivity of the megamouth shark (Megachasma pelagios)

PubMed Central

Joung, Shoou Jeng; Yu, Chi-Ju; Hsu, Hua-Hsun; Tsai, Wen-Pei; Liu, Kwang Ming

2018-01-01

The megamouth shark (Megachasma pelagios) was described as a new species in 1983. Since then, only ca. 100 individuals have been observed or caught. Its horizontal migration, dispersal, and connectivity patterns are still unknown due to its rarity. Two genetic markers were used in this study to reveal its genetic diversity and connectivity pattern. This approach provides a proxy to indirectly measure gene flow between populations. Tissues from 27 megamouth sharks caught by drift nets off the Hualien coast (eastern Taiwan) were collected from 2013 to 2015. With two additional tissue samples from megamouths caught in Baja California, Mexico, and sequences obtained from GenBank, we were able to perform the first population genetic analyses of the megamouth shark. The mtDNA cox1 gene and a microsatellite (Loc 6) were sequenced and analyzed. Our results showed that there is no genetic structure in the megamouth shark, suggesting a possible panmictic population. Based on occurrence data, we also suggest that the Kuroshio region, including the Philippines, Taiwan, and Japan, may act as a passageway for megamouth sharks to reach their feeding grounds from April to August. Our results provide insights into the dispersal and connectivity of megamouth sharks. Future studies should focus on collecting more samples and conducting satellite tagging to better understand the global migration and connectivity pattern of the megamouth shark. PMID:29527411

In vivo investigation on connective tissue healing to polished surfaces with different surface wettability.

PubMed

Kloss, Frank R; Steinmüller-Nethl, Doris; Stigler, Robert G; Ennemoser, Thomas; Rasse, Michael; Hächl, Oliver

2011-07-01

Connective tissue in contact to transgingival/-dermal implants presents itself as tight scar formation. Although rough surfaces support the attachment they increase bacterial colonisation as well. In contrast to surface roughness, little is known about the influence of surface wettability on soft-tissue healing in vivo. We therefore investigated the influence of different surface wettabilities on connective tissue healing at polished implant surfaces in vivo. Three polished experimental groups (titanium, titanium coated with hydrophobic nano-crystalline diamond (H-NCD) and titanium coated with hydrophilic nano-crystalline diamond (O-NCD) were inserted into the subcutaneous connective tissue of the abdominal wall of 24 rats. Animals were sacrificed after 1 and 4 weeks resulting in eight specimen per group per time point. Specimen were subjected to histological evaluation (van Giesson's staining) and immunohistochemistry staining for proliferating cell nuclear antigen (PCNA), fibronectin and tumour necrosis factor-alpha (TNF-α). Histological evaluation revealed dense scar formation at the titanium and H-NCD surfaces. In contrast, the connective tissue was loose at the O-NCD surface with a significantly higher number of cells after 4 weeks. O-NCD demonstrated a strong expression of PCNA and fibronectin but a weak expression of TNF-α. In contrast, the PCNA and fibronectin expression was low at the titanium and H-NCD, with a strong signal of TNF-α at the H-NCD surface. Hydrophilicity influences the connective tissue healing at polished implant surfaces in vivo positively. The attachment of connective tissue and the number of cells in contact to the surface were increased. Moreover, the inflammatory response is decreased at the hydrophilic surface. © 2010 John Wiley & Sons A/S.

Reappraisal of the ligament of Henle (ligamentum inguinale internum mediale; Henle, 1871): a topohistological study using Korean foetuses.

PubMed

Yang, J D; Hwang, H P; Kim, J H; Murakami, G; Rodríguez-Vázquez, J F; Cho, B H

2013-05-01

Ligament of Henle is one of muscle-associated connective tissues of the rectus abdominis muscle, but it has been confused with the conjoint tendon (a common aponeurosis for insertion of the inferomedial end of the obliquus internus and transversus abdominis muscles). To reconsider the inguinal connective tissue structures, we examined 20 mid-term foetuses (10 males and 10 females) at approximately 14-20 weeks of gestation (crown rump length 100-170 mm). In female horizontal sections, we consistently found the ligament of Henle asa wing-like aponeurosis extending from the lateral margin of the rectus tendon behind the superficial inguinal ring. The ligament was separated from and located behind the conjoint tendon. In all male foetuses, instead of the ligament, the conjoint tendon was evident behind the superficial ring and it winded around the posterior aspect of the spermatic cord. Therefore, although a limited number of specimens were examined, the ligament of Henle was likely to be a female-specific structure. The ligament of Henle, if developed well, may provide an arch-like structure suitable for a name "falx inguinalis" instead of the inferomedial end ofthe conjoint tendon. In addition, a covering fascia of the iliopsoas muscle joined the posterior wall of the inguinal canal in male, but not in female, specimens.

Novel aspects of intrinsic and extrinsic aging of human skin: beneficial effects of soy extract.

PubMed

Südel, Kirstin M; Venzke, Kirsten; Mielke, Heiko; Breitenbach, Ute; Mundt, Claudia; Jaspers, Sören; Koop, Urte; Sauermann, Kirsten; Knussman-Hartig, Elke; Moll, Ingrid; Gercken, Günther; Young, Anthony R; Stäb, Franz; Wenck, Horst; Gallinat, Stefan

2005-01-01

Biochemical and structural changes of the dermal connective tissue substantially contribute to the phenotype of aging skin. To study connective tissue metabolism with respect to ultraviolet (UV) exposure, we performed an in vitro (human dermal fibroblasts) and an in vivo complementary DNA array study in combination with protein analysis in young and old volunteers. Several genes of the collagen metabolism such as Collagen I, III and VI as well as heat shock protein 47 and matrix metalloproteinase-1 are expressed differentially, indicating UV-mediated effects on collagen expression, processing and degradation. In particular, Collagen I is time and age dependently reduced after a single UV exposure in human skin in vivo. Moreover, older subjects display a lower baseline level and a shorter UV-mediated increase in hyaluronan (HA) levels. To counteract these age-dependent changes, cultured fibroblasts were treated with a specific soy extract. This treatment resulted in increased collagen and HA synthesis. In a placebo-controlled in vivo study, topical application of an isoflavone-containing emulsion significantly enhanced the number of dermal papillae per area after 2 weeks. Because the flattening of the dermal-epidermal junction is the most reproducible structural change in aged skin, this soy extract appears to rejuvenate the structure of mature skin.

[The gastrointestinal tract microbiom in connective tissue diseases].

PubMed

Krajewska-Włodarczyk, Magdalena

Factors such as genetics, the environment, infections, and the human body microbiota, mainly gastrointestinal tract microbiota may play a role in the pathogenesis of autoimmune disorders. There is an increasing evidence that suggest an association between gastrointestinal tract dysbiosis, and in particular gut dysbiosis, and connective tissue diseases but it still remains unclear whether alterations in the microbiome are a pathogenic cause or an effect of autoimmune disease. Given the strong variability and abundance of microbes living in close relation with human host, it becomes a difficult task to define what should be considered the normal or the favorable microbiome. Further studies are needed to establish how the human microbiome contributes to disease susceptibility, and to characterize the role of microbial diversity in the pathogenesis of connective tissue diseases and their clinical manifestations. The identification of dysbiosis specific for certain connective tissue diseases may help in the development of an individualized management for each patient. This review aims to summarize current data on the role of the gastrointestinal tract microbiome in connective tissue diseases.

A theoretical approach of the relationships between collagen content, collagen cross-links and meat tenderness.

PubMed

Lepetit, J

2007-05-01

This work concerns the relationship between meat tenderness and the rubber-like properties, i.e. pressure and elastic modulus, that endomysium and perimysium connective tissues develop when meat has been heated to a temperature above which collagen contracts. For rest length meats with similar intramuscular connective tissue morphology, and which are at the same ageing state and pH, the elastic modulus of the collagenous fraction of connective tissues is approximately proportional to the total number of collagen cross-links present per volume of meat. Calculations from various published experiments concerned with the effect on tenderness of muscle type, animal age, type, and sex from different species show that this modulus follows most of the variations of meat toughness. Moreover, the proportionality between the increase in this elastic modulus and the increase in meat toughness approaches unity in situations where toughness mainly depends on connective tissues. This work demonstrates the decisive role of rubber-like properties of connective tissues in meat tenderness variations.

Surgical treatment and histopathology of different forms of olecranon and presternal bursitis in cattle and buffalo

PubMed Central

Fathy, Ahmed

2006-01-01

Thirty seven cases of bursitis presented to our Veterinary Teaching Hospital from 2001 to 2005. There were 10 adult female buffalos with olecranon bursitis (one had bilateral bursitis) and 26 calves (7 cattle and 19 buffalos, 16 males and 10 females) with presternal bursitis. There were 10 out of 11 cases of olecranon bursitis and 21 out of 26 cases of presternal bursitis with different forms (cystic, proliferative and fibrous) that were removed surgically. The remaining 6 cases, cystic bursitis (olecranon = 1, presternal = 5), were treated by aspiration of their contents and injection of 4% iodine tincture intrabursally. Only 2 cases recovered, 3 cases progressed to fibrosis and required further surgical treatment 2 to 3 weeks later, and 1 case continued to have a cystic lesion. Histopathological examination of tissue specimens from different forms of bursitis revealed that the acquired bursae were generally lined with synovial-like membrane formed from 2-3 cellular layers that covered the connective tissue capsule. The connective tissue capsule differed from one type to another and consisted of fibrous tissues containing numerous small blood vessels, blood capillaries, lymphatics and nerves. There was also evidence for inflammation within the capsule represented by congestion of blood vessels and the presence of perivascular inflammatory cells, mostly mononuclear. In conclusion, surgical treatment was successful and effective for treatment of olecranon and presternal bursitis particularly for the chronic proliferative and fibrous form in cattle and buffalo. The histological structure of the acquired bursae was relatively similar consisting of a synovial-like membrane and a connective tissue capsule with varying degrees of the inflammatory process. PMID:16871025

Visualisation of Collagen in fixed skeletal muscle tissue using fluorescently tagged Collagen binding protein CNA35.

PubMed

Mohammadkhah, Melika; Simms, Ciaran K; Murphy, Paula

2017-02-01

Detection and visualisation of Collagen structure are important to understand the relationship between mechanical behaviour and microstructure in skeletal muscle since Collagen is the main structural protein in animal connective tissues, and is primarily responsible for their passive load-bearing properties. In the current study, the direct detection and visualization of Collagen using fluorescently tagged CNA35 binding protein (fused to EGFP or tdTomato) is reported for the first time on fixed skeletal muscle tissue. This Technical Note also establishes a working protocol by examining tissue preparation, dilution factor, exposure time etc. for sensitivity and specificity. Penetration of the binding protein into intact mature skeletal muscle was found to be very limited, but detection works well on tissue sections with higher sensitivity on wax embedded sections compared to frozen sections. CNA35 fused to tdTomato has a higher sensitivity than CNA35 fused to EGFP but both show specific detection. Best results were obtained with 15μm wax embedded sections, with blocking of non-specific binding in 1% BSA and antigen retrieval in Sodium Citrate. There was a play-off between dilution of the binding protein and time of incubation but both CNA35-tdTomato and CNA35-EGFP worked well with approximately 100μg/ml of purified protein with overnight incubation, while CNA35-tdTomato could be utilized at 5 fold less concentration. This approach can be applied to study the relationship between skeletal muscle micro-structure and to observe mechanical response to applied deformation. It can be used more broadly to detect Collagen in a variety of fixed tissues, useful for structure-functions studies, constitutive modelling, tissue engineering and assessment of muscle tissue pathologies. Copyright © 2016 Elsevier Ltd. All rights reserved.

Extracellular Matrix Remodeling: The Common Denominator in Connective Tissue DiseasesPossibilities for Evaluation and Current Understanding of the Matrix as More Than a Passive Architecture, but a Key Player in Tissue Failure

PubMed Central

Nielsen, Mette J.; Sand, Jannie M.; Henriksen, Kim; Genovese, Federica; Bay-Jensen, Anne-Christine; Smith, Victoria; Adamkewicz, Joanne I.; Christiansen, Claus; Leeming, Diana J.

2013-01-01

Abstract Increased attention is paid to the structural components of tissues. These components are mostly collagens and various proteoglycans. Emerging evidence suggests that altered components and noncoded modifications of the matrix may be both initiators and drivers of disease, exemplified by excessive tissue remodeling leading to tissue stiffness, as well as by changes in the signaling potential of both intact matrix and fragments thereof. Although tissue structure until recently was viewed as a simple architecture anchoring cells and proteins, this complex grid may contain essential information enabling the maintenance of the structure and normal functioning of tissue. The aims of this review are to (1) discuss the structural components of the matrix and the relevance of their mutations to the pathology of diseases such as fibrosis and cancer, (2) introduce the possibility that post-translational modifications (PTMs), such as protease cleavage, citrullination, cross-linking, nitrosylation, glycosylation, and isomerization, generated during pathology, may be unique, disease-specific biochemical markers, (3) list and review the range of simple enzyme-linked immunosorbent assays (ELISAs) that have been developed for assessing the extracellular matrix (ECM) and detecting abnormal ECM remodeling, and (4) discuss whether some PTMs are the cause or consequence of disease. New evidence clearly suggests that the ECM at some point in the pathogenesis becomes a driver of disease. These pathological modified ECM proteins may allow insights into complicated pathologies in which the end stage is excessive tissue remodeling, and provide unique and more pathology-specific biochemical markers. PMID:23046407

Tissue engineering therapies for the vocal fold lamina propria.

PubMed

Kutty, Jaishankar K; Webb, Ken

2009-09-01

The vocal folds are laryngeal connective tissues with complex matrix composition/organization that provide the viscoelastic mechanical properties required for voice production. Vocal fold injury results in alterations in tissue structure and corresponding changes in tissue biomechanics that reduce vocal quality. Recent work has begun to elucidate the biochemical changes underlying injury-induced pathology and to apply tissue engineering principles to the prevention and reversal of vocal fold scarring. Based on the extensive history of injectable biomaterials in laryngeal surgery, a major focus of regenerative therapies has been the development of novel scaffolds with controlled in vivo residence time and viscoelastic properties approximating the native tissue. Additional strategies have included cell transplantation and delivery of the antifibrotic cytokine hepatocyte growth factor, as well as investigation of the effects of the unique vocal fold vibratory microenvironment using in vitro dynamic culture systems. Recent achievements of significant reductions in fibrosis and improved recovery of native tissue viscoelasticity and vibratory/functional performance in animal models are rapidly moving vocal fold tissue engineering toward clinical application.

Quantification of loading in biomechanical testing: the influence of dissection sequence.

PubMed

Funabashi, Martha; El-Rich, Marwan; Prasad, Narasimha; Kawchuk, Gregory N

2015-09-18

Sequential dissection is a technique used to investigate loads experienced by articular tissues. When the joint of interest is tested in an unconstrained manner, its kinematics change with each tissue removal. To address this limitation, sufficiently rigid robots are used to constrain joint kinematics. While this approach can quantify loads experienced by each tissue, it does not assure similar results when removal order is changed. Specifically, structure loading is assumed to be independent of removal order if the structure behaves linearly (i.e. principle of superposition applies), but dependent on removal order when response is affected by material and/or geometry nonlinearities and/or viscoelasticiy (e.g. biological tissues). Therefore, this experiment was conducted to evaluate if structure loading created through robotic testing is dependent on the order in which connectors are removed. Six identical models were 3D printed. Each model was composed of 2 rigid bodies and 3 connecting structures with nonlinear time-dependent behavior. To these models, pure rotations were applied about a predefined static center of rotation using a parallel robot. A unique dissection sequence was used for each of the six models and the same movements applied robotically after each dissection. When comparing the moments experienced by each structure between different removal sequences, a statistically significant difference (p<0.05) was observed. These results suggest that even in an optimized environment, the sequence in which nonlinear viscoelastic structures are removed influence model loading. These findings support prior work suggesting that tissue loads obtained from robotic testing are specific to removal order. Copyright © 2015 Elsevier Ltd. All rights reserved.

[Use of porous permeable titanium nickelide implants in surgery of the frontal and maxillary sinuses (a clinical-experimental study)].

PubMed

Starokha, A V; Itin, V I; Kovrizhnykh, V V; Ryzhov, A I; Monasevich, L A

1990-01-01

The purpose of the investigation was to study the efficacy of closing the bone defect in facial walls of the frontal and maxillary sinuses, formed as a result of their purulent inflammation, by porous permeable titanium nickelide. Analysis of the experimental data (18 dogs) and clinical observations (20 patients in whom the anatomic structure and function of frontal and maxillary sinuses with osteomyelitis were restored by an antibiotic pooling implantation material) gives evidence that the material can be well used to reconstruct an organ with an infected wound. The porous structure of the bioinert graft facilitates the ingrowth of osteogenic tissues, which becomes packed in the bone matrix without any intermediate connective tissue layer.

Multiple essential MT1-MMP functions in tooth root formation, dentinogenesis, and tooth eruption

PubMed Central

Wimer, H.F.; Yamada, S.S.; Yang, T.; Holmbeck, K.; Foster, B.L.

2016-01-01

Membrane-type matrix metalloproteinase 1 (MT1-MMP) is a transmembrane zinc-endopeptidase that breaks down extracellular matrix components, including several collagens, during tissue development and physiological remodeling. MT1-MMP-deficient mice (MT1-MMP−/−) feature severe defects in connective tissues, such as impaired growth, osteopenia, fibrosis, and conspicuous loss of molar tooth eruption and root formation. In order to define the functions of MT1-MMP during root formation and tooth eruption, we analyzed the development of teeth and surrounding tissues in the absence of MT1-MMP. In situ hybridization showed that MT1-MMP was widely expressed in cells associated with teeth and surrounding connective tissues during development. Multiple defects in dentoalveolar tissues were associated with loss of MT1-MMP. Root formation was inhibited by defective structure and function of Hertwig's epithelial root sheath (HERS). However, no defect was found in creation of the eruption pathway, suggesting that tooth eruption was hampered by lack of alveolar bone modeling/remodeling coincident with reduced periodontal ligament (PDL) formation and integration with the alveolar bone. Additionally, we identified a significant defect in dentin formation and mineralization associated with the loss of MT1-MMP. To segregate these multiple defects and trace their cellular origin, conditional ablation of MT1-MMP was performed in epithelia and mesenchyme. Mice featuring selective loss of MT1-MMP activity in the epithelium were indistinguishable from wild type mice, and importantly, featured a normal HERS structure and molar eruption. In contrast, selective knock-out of MT1-MMP in Osterix-expressing mesenchymal cells, including osteoblasts and odontoblasts, recapitulated major defects from the global knock-out including altered HERS structure, short roots, defective dentin formation and mineralization, and reduced alveolar bone formation, although molars were able to erupt. These data indicate that MT1-MMP activity in the dental mesenchyme, and not in epithelial-derived HERS, is essential for proper tooth root formation and eruption. In summary, our studies point to an indispensable role for MT1-MMP-mediated matrix remodeling in tooth eruption through effects on bone formation, soft tissue remodeling and organization of the follicle/PDL region. PMID:26780723

The echinoderm collagen fibril: a hero in the connective tissue research of the 1990s.

PubMed

Szulgit, Greg

2007-07-01

Collagen fibrils are some of the most-abundant and important extracellular structures in our bodies, yet we are unsure of their shape and size. This is largely due to an inherent difficulty in isolating them from their surrounding tissues. Echinoderms have collagenous tissues that are similar to ours in many ways, yet they can be manipulated to easily relinquish their collagen fibrils, providing an excellent opportunity to study native fibrillar structure. In the early 1990s, they were found to defy the commonly accepted fibrillar model of the time in that they were much shorter, they were shaped like double-ended spindles, and their centers exhibited a reversal in molecular polarity. Realization of these features helped to reform the questions that were being asked about vertebrate fibrils, shifting the focus toward shape and size. Since then, researchers working with both groups (echinoderms and vertebrates) have worked together to find the structure of native fibrils. This information will be fundamental in understanding what holds collagenous tissues together at the fibrillar level, and could have important implications for people with Ehlers-Danlos syndrome. (c) 2007 Wiley Periodicals, Inc.

Histological Evaluation of Selected Organs of the Eurasian Beavers (Castor fiber) Inhabiting Poland.

PubMed

Dolka, I; Giżejewska, A; Giżejewski, Z; Kluciński, W; Kołodziejska, J

2015-10-01

There is a general scarcity of data on the histological structure of major organs in the Eurasian beaver (Castor fiber). This study presents the histological characteristics of beaver organs such as the liver, spleen, cardiac muscle, lungs and kidneys. Tissue samples were collected from 21 beavers and analysed. Selected samples of tail tissue were additionally examined. Tissue samples were placed in neutral buffered formalin and embedded in paraffin. 4-μm-thick sections were stained with haematoxylin and eosin, and other staining techniques were also used. Scant amounts of inter-lobular connective tissue were found in the liver. Ion or copper deposition was not observed, but scattered cytoplasmic glycogen deposits were present in hepatocytes. Our results suggest that beavers have defensive rather than storage spleens. Interestingly, the presence of melanin in splenic red pulp was noted. The histological structure of the examined organs closely resembled that of other rodent species. According to our knowledge, this is the first study evaluating the histological structure of beaver organs. Nevertheless, precise characterization of the evaluated organs requires further work with the involvement of accurate and reliable techniques, such as molecular biology or electron microscopy methods. © 2014 Blackwell Verlag GmbH.

Alterations of Dermal Connective Tissue Collagen in Diabetes: Molecular Basis of Aged-Appearing Skin

PubMed Central

Argyropoulos, Angela J.; Robichaud, Patrick; Balimunkwe, Rebecca Mutesi; Fisher, Gary J.; Hammerberg, Craig; Yan, Yan

2016-01-01

Alterations of the collagen, the major structural protein in skin, contribute significantly to human skin connective tissue aging. As aged-appearing skin is more common in diabetes, here we investigated the molecular basis of aged-appearing skin in diabetes. Among all known human matrix metalloproteinases (MMPs), diabetic skin shows elevated levels of MMP-1 and MMP-2. Laser capture microdissection (LCM) coupled real-time PCR indicated that elevated MMPs in diabetic skin were primarily expressed in the dermis. Furthermore, diabetic skin shows increased lysyl oxidase (LOX) expression and higher cross-linked collagens. Atomic force microscopy (AFM) further indicated that collagen fibrils were fragmented/disorganized, and key mechanical properties of traction force and tensile strength were increased in diabetic skin, compared to intact/well-organized collagen fibrils in non-diabetic skin. In in vitro tissue culture system, multiple MMPs including MMP-1 and MM-2 were induced by high glucose (25 mM) exposure to isolated primary human skin dermal fibroblasts, the major cells responsible for collagen homeostasis in skin. The elevation of MMPs and LOX over the years is thought to result in the accumulation of fragmented and cross-linked collagen, and thus impairs dermal collagen structural integrity and mechanical properties in diabetes. Our data partially explain why old-looking skin is more common in diabetic patients. PMID:27104752

[Ultrasound dissection in laparoscopic cholecystectomy].

PubMed

Horstmann, R; Kern, M; Joosten, U; Hohlbach, G

1993-01-01

An ultrasound dissector especially developed for laparoscopic surgery was used during laparoscopic cholecystectomy on 34 patients. The ultrasound power, the volume of suction and irrigation could be determined individually at the generator and activated during the operation with a foot pedal. With the dissector it was possible to fragmentate, emulgate and aspirate simultaneously fat tissue as well as infected edematous structures. The cystic artery and cystic duct, small vessels, lymphatic and connective tissue were not damaged. Therefore this system seems to be excellent for the preparation of Calot's trigonum and blunt dissection of the gallbladder out of its bed, particularly in fatty, acute or chronic infected tissue. No complications were observed within the peri- and postoperative period.

Direct microCT imaging of non-mineralized connective tissues at high resolution.

PubMed

Naveh, Gili R S; Brumfeld, Vlad; Dean, Mason; Shahar, Ron; Weiner, Steve

2014-01-01

The 3D imaging of soft tissues in their native state is challenging, especially when high resolution is required. An X-ray-based microCT is, to date, the best choice for high resolution 3D imaging of soft tissues. However, since X-ray attenuation of soft tissues is very low, contrasting enhancement using different staining materials is needed. The staining procedure, which also usually involves tissue fixation, causes unwanted and to some extent unknown tissue alterations. Here, we demonstrate that a method that enables 3D imaging of soft tissues without fixing and staining using an X-ray-based bench-top microCT can be applied to a variety of different tissues. With the sample mounted in a custom-made loading device inside a humidity chamber, we obtained soft tissue contrast and generated 3D images of fresh, soft tissues with a resolution of 1 micron voxel size. We identified three critical conditions which make it possible to image soft tissues: humidified environment, mechanical stabilization of the sample and phase enhancement. We demonstrate the capability of the technique using different specimens: an intervertebral disc, the non-mineralized growth plate, stingray tessellated radials (calcified cartilage) and the collagenous network of the periodontal ligament. Since the scanned specimen is fresh an interesting advantage of this technique is the ability to scan a specimen under load and track the changes of the different structures. This method offers a unique opportunity for obtaining valuable insights into 3D structure-function relationships of soft tissues.

Candidate Cell and Matrix Interaction Domains on the Collagen Fibril, the Predominant Protein of Vertebrates*S⃞

PubMed Central

Sweeney, Shawn M.; Orgel, Joseph P.; Fertala, Andrzej; McAuliffe, Jon D.; Turner, Kevin R.; Di Lullo, Gloria A.; Chen, Steven; Antipova, Olga; Perumal, Shiamalee; Ala-Kokko, Leena; Forlino, Antonella; Cabral, Wayne A.; Barnes, Aileen M.; Marini, Joan C.; Antonio, James D. San

2008-01-01

Type I collagen, the predominant protein of vertebrates, polymerizes with type III and V collagens and non-collagenous molecules into large cable-like fibrils, yet how the fibril interacts with cells and other binding partners remains poorly understood. To help reveal insights into the collagen structure-function relationship, a data base was assembled including hundreds of type I collagen ligand binding sites and mutations on a two-dimensional model of the fibril. Visual examination of the distribution of functional sites, and statistical analysis of mutation distributions on the fibril suggest it is organized into two domains. The “cell interaction domain” is proposed to regulate dynamic aspects of collagen biology, including integrin-mediated cell interactions and fibril remodeling. The “matrix interaction domain” may assume a structural role, mediating collagen cross-linking, proteoglycan interactions, and tissue mineralization. Molecular modeling was used to superimpose the positions of functional sites and mutations from the two-dimensional fibril map onto a three-dimensional x-ray diffraction structure of the collagen microfibril in situ, indicating the existence of domains in the native fibril. Sequence searches revealed that major fibril domain elements are conserved in type I collagens through evolution and in the type II/XI collagen fibril predominant in cartilage. Moreover, the fibril domain model provides potential insights into the genotype-phenotype relationship for several classes of human connective tissue diseases, mechanisms of integrin clustering by fibrils, the polarity of fibril assembly, heterotypic fibril function, and connective tissue pathology in diabetes and aging. PMID:18487200

Candidate Cell and Matrix Interaction Domains on the Collagen Fibril, the Predominant Protein of Vertebrates

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sweeney, Shawn M.; Orgel, Joseph P.; Fertala, Andrzej

Type I collagen, the predominant protein of vertebrates, polymerizes with type III and V collagens and non-collagenous molecules into large cable-like fibrils, yet how the fibril interacts with cells and other binding partners remains poorly understood. To help reveal insights into the collagen structure-function relationship, a data base was assembled including hundreds of type I collagen ligand binding sites and mutations on a two-dimensional model of the fibril. Visual examination of the distribution of functional sites, and statistical analysis of mutation distributions on the fibril suggest it is organized into two domains. The 'cell interaction domain' is proposed to regulatemore » dynamic aspects of collagen biology, including integrin-mediated cell interactions and fibril remodeling. The 'matrix interaction domain' may assume a structural role, mediating collagen cross-linking, proteoglycan interactions, and tissue mineralization. Molecular modeling was used to superimpose the positions of functional sites and mutations from the two-dimensional fibril map onto a three-dimensional x-ray diffraction structure of the collagen microfibril in situ, indicating the existence of domains in the native fibril. Sequence searches revealed that major fibril domain elements are conserved in type I collagens through evolution and in the type II/XI collagen fibril predominant in cartilage. Moreover, the fibril domain model provides potential insights into the genotype-phenotype relationship for several classes of human connective tissue diseases, mechanisms of integrin clustering by fibrils, the polarity of fibril assembly, heterotypic fibril function, and connective tissue pathology in diabetes and aging.« less

The serum levels of connective tissue growth factor in patients with systemic lupus erythematosus and lupus nephritis.

PubMed

Wang, F-M; Yu, F; Tan, Y; Liu, G; Zhao, M-H

2014-06-01

The expression of connective tissue growth factor mRNA in human kidneys may serve as an early marker for lupus nephritis progression. Therefore, we speculated that connective tissue growth factor may be involved in the pathogenesis of systemic lupus erythematosus and lupus nephritis. In this study, we set out to investigate the associations between serum connective tissue growth factor levels and clinicopathological features of patients with systemic lupus erythematosus and lupus nephritis. Serum samples from patients with non-renal systemic lupus erythematosus, renal biopsy-proven lupus nephritis and healthy control subjects were detected by enzyme-linked immunosorbent assay for serum connective tissue growth factor levels. The associations between connective tissue growth factor levels and clinicopathological features of the patients were further analysed. The levels of serum connective tissue growth factor in patients with non-renal systemic lupus erythematosus and lupus nephritis were both significantly higher than those in the normal control group (34.14 ± 12.17 ng/ml vs. 22.8 ± 3.0 ng/ml, p<0.001; 44.1 ± 46.8 ng/ml vs. 22.8 ± 3.0 ng/ml, p = 0.035, respectively). There was no significant difference of the serum connective tissue growth factor levels between non-renal systemic lupus erythematosus and lupus nephritis group (34.14 ± 12.17 ng/ml vs. 44.1 ± 46.8 ng/ml, p = 0.183). Serum connective tissue growth factor levels were significantly higher in lupus nephritis patients with the following clinical manifestations, including anaemia (51.3 ± 51.4 ng/ml vs. 23.4 ± 9.7 ng/ml, p<0.001) and acute renal failure (85.5 ± 75.0 ng/ml vs. 31.2 ± 21.8 ng/ml, p = 0.002). Serum connective tissue growth factor levels in class IV were significantly higher than that in class II, III and V (57.6 ± 57.5 ng/ml vs. 18.7 ± 6.4 ng/ml, p = 0.019; 57.6 ± 57.5 ng/ml vs. 25.2 ± 14.9 ng/ml, p = 0.006; 57.6 ± 57.5 ng/ml vs. 30.5 ± 21.3 ng/ml, p = 0.017, respectively). Serum connective tissue growth factor levels were significantly higher in those with both active/chronic lesions than those in those with active lesions only in either class IV (84.9 ± 69.6 ng/ml vs. 40.0 ± 40.2 ng/ml, p = 0.001) or in combination of class III and IV lupus nephritis (63.3 ± 63.4 ng/ml vs. 38.3 ± 37.9 ng/ml, p = 0.035, respectively). Serum connective tissue growth factor levels were negatively associated with estimated glomerular filtration rate (r = -0.46, p<0.001) and positively associated with interstitial inflammation (r = 0.309, p = 0.002) and interstitial fibrosis (r = 0.287, p = 0.004). Serum connective tissue growth factor level was a risk factor for doubling of serum creatinine in lupus nephritis (p<0.001, hazard ratio = 1.015, 95% confidence intervals 1.008-1.022) in univariate analysis. Serum connective tissue growth factor levels were significantly higher in lupus and correlated with chronic renal interstitial injury and doubling of serum creatinine in patients with lupus nephritis. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Voluntary exercise improves murine dermal connective tissue status in high-fat diet-induced obesity.

PubMed

Lőrincz, Kende; Haluszka, Dóra; Kiss, Norbert; Gyöngyösi, Nóra; Bánvölgyi, András; Szipőcs, Róbert; Wikonkál, Norbert M

2017-04-01

Obesity is a risk factor for several cardiovascular and metabolic diseases. Its influence on the skin is less obvious, yet certain negative effects of adipose tissue inflammation on the dermis have been suggested. Excess weight is closely associated with sedentary behavior, so any increase in physical activity is considered beneficial against obesity. To investigate the effects of obesity and physical exercise on the skin, we established a mouse model in which mice were kept either on a high-fat diet or received standard chow. After the two groups achieved a significant weight difference, physical exercise was introduced to both. Animals were given the opportunity to perform voluntary exercise for 40 min daily in a hamster wheel for a period of 8 weeks. We evaluated the status of the dermis at the beginning and at the end of the exercise period by in vivo nonlinear microscopy. Obese mice kept on high-fat diet lost weight steadily after they started to exercise. In the high-fat diet group, we could detect significantly larger adipocytes and a thicker layer of subcutaneous tissue; both changes started to normalize after exercise. Nonlinear microscopy revealed an impaired collagen structure in obese mice that improved considerably after physical activity was introduced. With the ability to detect damage on collagen structure, we set out to address the question whether this process is reversible. With the use of a novel imaging method, we were able to show the reversibility of connective tissue deterioration as a benefit of physical exercise.

Human Periodontal Cells Demonstrate Osteoblast-Like and Fibroblast-Like Characteristics in Tissue Culture

DTIC Science & Technology

1989-05-05

gingiva and periodontal ligament emphasizes similarities between the connective tissues of gingiva and periodontal ligament. Possible regeneration of...Clinicians and researchers gradually realized the importance of periodontal ligament granulation tissue in periodontal regeneration (Melcher, 1976...isolated osseous defects. The guided tissue regeneration technique uses membrane filters to isolate healing periodontal defects from gingival connective

Periodontal Wound Healing Responses to Varying Oxygen Concentrations and Atmospheric Pressures.

DTIC Science & Technology

1986-05-01

Presumably, epithelial and gingival connective tissue exclusion allowed periodontal ligament cells to repopulate the wound and to regenerate a new...However, it seems clear that the periodontal ligament cells provide a major source of connective tissue attachment and regeneration (Nyman et al., 1982a...Connective Tissue Regeneration to Periodontally Diseased Teeth. J. Perio. Res. 15:1. Davis, J. C., Dunn, J. M., Gates, G. A. and Heimbach, R. D. 1979

An update of neurological manifestations of vasculitides and connective tissue diseases: a literature review

PubMed Central

Bougea, Anastasia; Anagnostou, Evangelos; Spandideas, Nikolaos; Triantafyllou, Nikolaos; Kararizou, Evangelia

2015-01-01

Vasculitides comprise a heterogeneous group of autoimmune disorders, occurring as primary or secondary to a broad variety of systemic infectious, malignant or connective tissue diseases. The latter occur more often but their pathogenic mechanisms have not been fully established. Frequent and varied central and peripheral nervous system complications occur in vasculitides and connective tissue diseases. In many cases, the neurological disorders have an atypical clinical course or even an early onset, and the healthcare professionals should be aware of them. The purpose of this brief review was to give an update of the main neurological disorders of common vasculitis and connective tissue diseases, aiming at accurate diagnosis and management, with an emphasis on pathophysiologic mechanisms. PMID:26313435

The Zinc Transporter SLC39A13/ZIP13 Is Required for Connective Tissue Development; Its Involvement in BMP/TGF-β Signaling Pathways

PubMed Central

Shimoda, Shinji; Mishima, Kenji; Higashiyama, Hiroyuki; Idaira, Yayoi; Asada, Yoshinobu; Kitamura, Hiroshi; Yamasaki, Satoru; Hojyo, Shintaro; Nakayama, Manabu; Ohara, Osamu; Koseki, Haruhiko; dos Santos, Heloisa G.; Bonafe, Luisa; Ha-Vinh, Russia; Zankl, Andreas; Unger, Sheila; Kraenzlin, Marius E.; Beckmann, Jacques S.; Saito, Ichiro; Rivolta, Carlo; Ikegawa, Shiro; Superti-Furga, Andrea; Hirano, Toshio

2008-01-01

Background Zinc (Zn) is an essential trace element and it is abundant in connective tissues, however biological roles of Zn and its transporters in those tissues and cells remain unknown. Methodology/Principal Findings Here we report that mice deficient in Zn transporter Slc39a13/Zip13 show changes in bone, teeth and connective tissue reminiscent of the clinical spectrum of human Ehlers-Danlos syndrome (EDS). The Slc39a13 knockout (Slc39a13-KO) mice show defects in the maturation of osteoblasts, chondrocytes, odontoblasts, and fibroblasts. In the corresponding tissues and cells, impairment in bone morphogenic protein (BMP) and TGF-β signaling were observed. Homozygosity for a SLC39A13 loss of function mutation was detected in sibs affected by a unique variant of EDS that recapitulates the phenotype observed in Slc39a13-KO mice. Conclusions/Significance Hence, our results reveal a crucial role of SLC39A13/ZIP13 in connective tissue development at least in part due to its involvement in the BMP/TGF-β signaling pathways. The Slc39a13-KO mouse represents a novel animal model linking zinc metabolism, BMP/TGF-β signaling and connective tissue dysfunction. PMID:18985159

A long-distance fluid transport pathway within fibrous connective tissues in patients with ankle edema.

PubMed

Li, Hongyi; Yang, Chongqing; Lu, Kuiyuan; Zhang, Liyang; Yang, Jiefu; Wang, Fang; Liu, Dongge; Cui, Di; Sun, Mingjun; Pang, Jianxin; Dai, Luru; Han, Dong; Liao, Fulong

2016-10-05

Although the microcirculatory dysfunctions of edema formation are well documented, the draining pattern of dermal edema lacks information. This study was to assess the potential drainage pathways of the interstitial fluid in patients with ankle edema using the anatomical and histological methods. Four amputees of lower leg participated in this study. Fluorescent imaging agent was injected into lateral ankle dermis in one volunteered patient before the amputation and three lower legs after the amputation. Physiologically in the volunteer or enhanced by cyclical compression on three amputated limbs, several fluorescent longitudinal pathways from ankle dermis to the broken end of the amputated legs were subsequently visualized and studied using histological methods, laser confocal microscopy and electron microscopy methods respectively. Interestingly, the fluorescent pathways confirmed to be fibrous connective tissues and the presence of two types: those of the cutaneous pathway (located in dermis or the interlobular septum among adipose tissues within the hypodermis) and those of the perivascular pathway (located in connective tissues surrounding the veins and the arteries). The intrinsic three-dimensional architecture of each fluorescent pathway was the longitudinally running and interconnected fibril bundles, upon which, an interfacial transport pathway within connective tissues was visualized by fluorescein. The current anatomical data suggested that a unique long-distance transport pathway composed of oriented fibrous connective tissues might play a pathophysiological role in draining dermal edema besides vascular circulations and provide novel understandings of general fibrous connective tissues in life science.

Passive mechanical properties of rat abdominal wall muscles suggest an important role of the extracellular connective tissue matrix.

PubMed

Brown, Stephen H M; Carr, John Austin; Ward, Samuel R; Lieber, Richard L

2012-08-01

Abdominal wall muscles have a unique morphology suggesting a complex role in generating and transferring force to the spinal column. Studying passive mechanical properties of these muscles may provide insights into their ability to transfer force among structures. Biopsies from rectus abdominis (RA), external oblique (EO), internal oblique (IO), and transverse abdominis (TrA) were harvested from male Sprague-Dawley rats, and single muscle fibers and fiber bundles (4-8 fibers ensheathed in their connective tissue matrix) were isolated and mechanically stretched in a passive state. Slack sarcomere lengths were measured and elastic moduli were calculated from stress-strain data. Titin molecular mass was also measured from single muscle fibers. No significant differences were found among the four abdominal wall muscles in terms of slack sarcomere length or elastic modulus. Interestingly, across all four muscles, slack sarcomere lengths were quite long in individual muscle fibers (>2.4 µm), and demonstrated a significantly longer slack length in comparison to fiber bundles (p < 0.0001). Also, the extracellular connective tissue matrix provided a stiffening effect and enhanced the resistance to lengthening at long muscle lengths. Titin molecular mass was significantly less in TrA compared to each of the other three muscles (p < 0.0009), but this difference did not correspond to hypothesized differences in stiffness. Copyright © 2012 Orthopaedic Research Society.

Sensory Innervation of the Nonspecialized Connective Tissues in the Low Back of the Rat

PubMed Central

Corey, Sarah M.; Vizzard, Margaret A.; Badger, Gary J.; Langevin, Helene M.

2011-01-01

Chronic musculoskeletal pain, including low back pain, is a worldwide debilitating condition; however, the mechanisms that underlie its development remain poorly understood. Pathological neuroplastic changes in the sensory innervation of connective tissue may contribute to the development of nonspecific chronic low back pain. Progress in understanding such potentially important abnormalities is hampered by limited knowledge of connective tissue's normal sensory innervation. The goal of this study was to evaluate and quantify the sensory nerve fibers terminating within the nonspecialized connective tissues in the low back of the rat. With 3-dimensional reconstructions of thick (30–80 μm) tissue sections we have for the first time conclusively identified sensory nerve fiber terminations within the collagen matrix of connective tissue in the low back. Using dye labeling techniques with Fast Blue, presumptive dorsal root ganglia cells that innervate the low back were identified. Of the Fast Blue-labeled cells, 60–88% also expressed calcitonin gene-related peptide (CGRP) immunoreactivity. Based on the immunolabeling with CGRP and the approximate size of these nerve fibers (≤2 μm) we hypothesize that they are Aδ or C fibers and thus may play a role in the development of chronic pain. PMID:21411968

Promise of periodontal ligament stem cells in regeneration of periodontium.

PubMed

Maeda, Hidefumi; Tomokiyo, Atsushi; Fujii, Shinsuke; Wada, Naohisa; Akamine, Akifumi

2011-07-28

A great number of patients around the world experience tooth loss that is attributed to irretrievable damage of the periodontium caused by deep caries, severe periodontal diseases or irreversible trauma. The periodontium is a complex tissue composed mainly of two soft tissues and two hard tissues; the former includes the periodontal ligament (PDL) tissue and gingival tissue, and the latter includes alveolar bone and cementum covering the tooth root. Tissue engineering techniques are therefore required for regeneration of these tissues. In particular, PDL is a dynamic connective tissue that is subjected to continual adaptation to maintain tissue size and width, as well as structural integrity, including ligament fibers and bone modeling. PDL tissue is central in the periodontium to retain the tooth in the bone socket, and is currently recognized to include somatic mesenchymal stem cells that could reconstruct the periodontium. However, successful treatment using these stem cells to regenerate the periodontium efficiently has not yet been developed. In the present article, we discuss the contemporary standpoints and approaches for these stem cells in the field of regenerative medicine in dentistry.

Micromechanical modeling of rate-dependent behavior of Connective tissues.

PubMed

Fallah, A; Ahmadian, M T; Firozbakhsh, K; Aghdam, M M

2017-03-07

In this paper, a constitutive and micromechanical model for prediction of rate-dependent behavior of connective tissues (CTs) is presented. Connective tissues are considered as nonlinear viscoelastic material. The rate-dependent behavior of CTs is incorporated into model using the well-known quasi-linear viscoelasticity (QLV) theory. A planar wavy representative volume element (RVE) is considered based on the tissue microstructure histological evidences. The presented model parameters are identified based on the available experiments in the literature. The presented constitutive model introduced to ABAQUS by means of UMAT subroutine. Results show that, monotonic uniaxial test predictions of the presented model at different strain rates for rat tail tendon (RTT) and human patellar tendon (HPT) are in good agreement with experimental data. Results of incremental stress-relaxation test are also presented to investigate both instantaneous and viscoelastic behavior of connective tissues. Copyright © 2017 Elsevier Ltd. All rights reserved.

Applications and Emerging Trends of Hyaluronic Acid in Tissue Engineering, as a Dermal Filler, and in Osteoarthritis Treatment

PubMed Central

Fakhari, Amir; Berkland, Cory

2013-01-01

Hyaluronic acid (HA) is a naturally occurring biodegradable polymer with a variety of applications in medicine including scaffolding for tissue engineering, dermatological fillers, and viscosupplementation for osteoarthritis treatment. HA is available in most connective tissues in body fluids such as synovial fluid and the vitreous humor of the eye. HA is responsible for several structural properties of tissues as a component of extracellular matrix (ECM) and is involved in cellular signaling. Degradation of HA is a step-wise process that can occur via enzymatic or non-enzymatic reactions. A reduction in HA mass or molecular weight via degradation or slowing of synthesis affects physical and chemical properties such as tissue volume, viscosity, and elasticity. This review addresses the distribution, turnover, and tissue-specific properties of HA. This information is used as context for considering recent products and strategies for modifying the viscoelastic properties of HA in tissue engineering, as a dermal filler, and in osteoarthritis treatment. PMID:23507088

Targeted Ablation of the Abcc6 Gene Results in Ectopic Mineralization of Connective Tissues

PubMed Central

Klement, John F.; Matsuzaki, Yasushi; Jiang, Qiu-Jie; Terlizzi, Joseph; Choi, Hae Young; Fujimoto, Norihiro; Li, Kehua; Pulkkinen, Leena; Birk, David E.; Sundberg, John P.; Uitto, Jouni

2005-01-01

Pseudoxanthoma elasticum (PXE), characterized by connective tissue mineralization of the skin, eyes, and cardiovascular system, is caused by mutations in the ABCC6 gene. ABCC6 encodes multidrug resistance-associated protein 6 (MRP6), which is expressed primarily in the liver and kidneys. Mechanisms producing ectopic mineralization as a result of these mutations remain unclear. To elucidate this complex disease, a transgenic mouse was generated by targeted ablation of the mouse Abcc6 gene. Abcc6 null mice were negative for Mrp6 expression in the liver, and complete necropsies revealed profound mineralization of several tissues, including skin, arterial blood vessels, and retina, while heterozygous animals were indistinguishable from the wild-type mice. Particularly striking was the mineralization of vibrissae, as confirmed by von Kossa and alizarin red stains. Electron microscopy revealed mineralization affecting both elastic structures and collagen fibers. Mineralization of vibrissae was noted as early as 5 weeks of age and was progressive with age in Abcc6−/− mice but was not observed in Abcc6+/− or Abcc6+/+ mice up to 2 years of age. A total body computerized tomography scan of Abcc6−/− mice revealed mineralization in skin and subcutaneous tissue as well as in the kidneys. These data demonstrate aberrant mineralization of soft tissues in PXE-affected organs, and, consequently, these mice recapitulate features of this complex disease. PMID:16135817

A fractal derivative model for the characterization of anomalous diffusion in magnetic resonance imaging

NASA Astrophysics Data System (ADS)

Liang, Yingjie; Ye, Allen Q.; Chen, Wen; Gatto, Rodolfo G.; Colon-Perez, Luis; Mareci, Thomas H.; Magin, Richard L.

2016-10-01

Non-Gaussian (anomalous) diffusion is wide spread in biological tissues where its effects modulate chemical reactions and membrane transport. When viewed using magnetic resonance imaging (MRI), anomalous diffusion is characterized by a persistent or 'long tail' behavior in the decay of the diffusion signal. Recent MRI studies have used the fractional derivative to describe diffusion dynamics in normal and post-mortem tissue by connecting the order of the derivative with changes in tissue composition, structure and complexity. In this study we consider an alternative approach by introducing fractal time and space derivatives into Fick's second law of diffusion. This provides a more natural way to link sub-voxel tissue composition with the observed MRI diffusion signal decay following the application of a diffusion-sensitive pulse sequence. Unlike previous studies using fractional order derivatives, here the fractal derivative order is directly connected to the Hausdorff fractal dimension of the diffusion trajectory. The result is a simpler, computationally faster, and more direct way to incorporate tissue complexity and microstructure into the diffusional dynamics. Furthermore, the results are readily expressed in terms of spectral entropy, which provides a quantitative measure of the overall complexity of the heterogeneous and multi-scale structure of biological tissues. As an example, we apply this new model for the characterization of diffusion in fixed samples of the mouse brain. These results are compared with those obtained using the mono-exponential, the stretched exponential, the fractional derivative, and the diffusion kurtosis models. Overall, we find that the order of the fractal time derivative, the diffusion coefficient, and the spectral entropy are potential biomarkers to differentiate between the microstructure of white and gray matter. In addition, we note that the fractal derivative model has practical advantages over the existing models from the perspective of computational accuracy and efficiency.

Hypericin-mediated selective photomodification of connective tissues

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hovhannisyan, V., E-mail: hovv@phys.ntu.edu.tw; Guo, H. W.; Chen, Y. F., E-mail: yfchen@phys.ntu.edu.tw

2014-12-29

Controllable modification of biological molecules and supramolecular components of connective tissue are important for biophysical and biomedical applications. Through the use of second harmonic generation imaging, two-photon fluorescence microscopy, and spectrofluorimetry, we found that hypericin, a natural pigment, induces photosensitized destruction of collagen fibers but does not affect elastic fibers and lipids in chicken tendon, skin, and blood vessels. We demonstrated the dynamics and efficiency of collagen photomodification and investigated mechanisms of this processes. Our results suggest that hypericin–mediated photoprocesses in biological tissues may be useful in biomedical applications that require selective modification of connective tissues.

Agminated Fibroblastic Conective Tissue Nevus: A New Clinical Presentation.

PubMed

Downey, Camila; Requena, Luis; Bagué, Silvia; Sánchez Martínez, Miquel Ángel; Lloreta, Josep; Baselga, Eulalia

2016-07-01

Connective tissue nevi are benign hamartomatous lesions in which one or several of the components of the dermis (collagen, elastin, glicosaminoglycans) show predominance or depletion. Recently, de Feraudy et al broadened the spectrum of connective tissue nevus, describing fibroblastic connective tissue nevus (FCTN), which is characterized by proliferation of CD34(+) cells of fibroblastic and myofibroblastic lineage. Only solitary papules and nodules have been described. We present the first case of FCTN with multiple agminated lesions on the leg of an infant and the difficulties encountered in the differential diagnosis with dermatofibrosarcoma protuberans. © 2016 Wiley Periodicals, Inc.

Validation of color Doppler sonography for evaluating relative displacement between the flexor tendon and subsynovial connective tissue.

PubMed

Tat, Jimmy; Kociolek, Aaron M; Keir, Peter J

2015-04-01

A common pathologic finding in carpal tunnel syndrome is fibrosis and thickening of the subsynovial connective tissue. This finding suggests an etiology of excessive shear forces, with relative longitudinal displacement between the flexor tendon and adjacent subsynovial connective tissue. The purpose of this study was to validate color Doppler sonography for measurement of tendon displacement over time. Eight unmatched fresh frozen cadaver arms were used to evaluate color Doppler sonography for measurement of tendon displacement. The middle flexor digitorum superficialis tendon was moved through a physiologic excursion of 20 mm at 3 different tendon velocities (50, 100, and 150 mm/s). We found that color Doppler sonography provided accurate measurement of tendon displacement, with absolute errors of -0.05 mm (50 mm/s), -1.24 mm (100 mm/s), and -2.36 mm (150 mm/s) on average throughout the tendon excursion range. Evaluating relative displacement between the tendon and subsynovial connective tissue during finger flexion-extension movements also offered insight into the gliding mechanism of the subsynovial connective tissue. During flexion, we observed a curvilinear increase in relative displacement, with greater differential motion at the end range of displacement, likely due to the sequential stretch of the fibrils between successive layers of the subsynovial connective tissue. In extension, there was a linear return in relative displacement, suggesting a different unloading mechanism characterized by uniform relaxation of fibrils. We demonstrated the validity of color Doppler displacement for use in the evaluation of relative motion. Color Doppler sonography is useful in our understanding of the behavior of the subsynovial connective tissue during tendon excursion, which may elucidate the role of finger motion in the etiology of shear injury. © 2015 by the American Institute of Ultrasound in Medicine.

Secular trends of pregnancies in women with inflammatory connective tissue disease.

PubMed

Wallenius, Marianne; Salvesen, Kjell Å; Daltveit, Anne K; Skomsvoll, Johan F

2015-11-01

This study examined secular trends in reproductive outcome in women with inflammatory connective tissue disease compared with reference deliveries from the general population. Historical cohort study based on data registered in the Medical Birth Register of Norway from 1967 to 2009. The study included singleton births in women recorded with connective tissue disease (n = 851) and reference deliveries from the general population (n = 2 437 110). Births were stratified in four periods, 1967-1979, 1980-1989, 1990-1999 and 2000-2009. Associations between connective tissue disease and maternal and perinatal outcomes by decade were assessed in logistic regression analyses and adjusted for maternal age at delivery and parity. In the 1970s, around 2.7 deliveries/year were registered for women with connective tissue disease (0.004% of all deliveries). This increased to 42 deliveries/year (0.07% of all deliveries) after 2000. Adjusted odds ratios (aOR) for cesarean section were 5.0 (95% CI 2.1-11.9) in the first and 1.8 (95% CI 1.4-2.3) in the last period. For preterm delivery the aOR decreased from 4.9 (95% CI 2.1-11.4) to 3.1 (95% CI 2.3-4.2) and the aOR for birthweight <2500 g changed from 7.3 (95% CI 3.3-16.3) to 4.1 (95% CI 3.0-5.6). An increasing number of births were observed over time among women with connective tissue disease. Adverse pregnancy outcomes were more common among women with connective tissue disease but risks have decreased over time. © 2015 Nordic Federation of Societies of Obstetrics and Gynecology.

[Mixed connective tissue disease: prevalence and clinical characteristics in African black, study of 7 cases in Gabon and review of the literature].

PubMed

Missounga, Landry; Ba, Josaphat Iba; Nseng Nseng Ondo, Ingrid Rosalie; Nziengui Madjinou, Maria Ines Carine; Malekou, Doris; Mouendou Mouloungui, Emeline Gracia; Nzengue, Emmanuel Ecke; Boguikouma, Jean Bruno; Kombila, Moussavou

2017-01-01

The literature reports that mixed connective tissue disease seems more frequent in the black population and among Asians. This study aims to determine the prevalence of mixed connective tissue disease (MCTD) among connective tissue disorders and all rheumatologic pathologies in a hospital population in Gabon as well as to describe the clinical features of this disease. We conducted a retrospective study by reviewing the medical records of patients treated for mixed connective tissue disease (Kasukawa criteria) and other entities of connective tissue disorders (ACR criteria) in the Division of Rheumatology at the University Hospital in Libreville between January 2010 and December 2015. For each case of MCTD the parameters studied were articular and extra-articular manifestations, anti-U1RNP antibodies levels, patient's evolution. Over a period of 6 years, data were collected by medical records of 7 patients out of 6050 patients and 67 cases of connective tissue disorders, reflecting a prevalence of 0.11% and 10.44% respectively. the 7 patients were women (100%), with an average age of 39.5 years. Articular manifestations included: polyarthritis, myalgias, chubby fingers and Raynaud's phenomenon in 87.5%, 87.5%, 28.6% and 14% respectively. The 7 patients had high anti-U1RNP antibodies levels, ranging between 5 and 35N (N≤ 7 IU). A case of death due to pulmonary arterial hypertension (PAH) was certified. This is the largest case series of MCTD reported in Black Africa. The disease seems to be rare among the black Africans; the reason could be genetic. The demographic and clinical aspects appear similar to those in Caucasians, Asians and Blacks except for a low frequency of Raynaud?s phenomenon among Blacks.

Maturation State and Matrix Microstructure Regulate Interstitial Cell Migration in Dense Connective Tissues.

PubMed

Qu, Feini; Li, Qing; Wang, Xiao; Cao, Xuan; Zgonis, Miltiadis H; Esterhai, John L; Shenoy, Vivek B; Han, Lin; Mauck, Robert L

2018-02-19

Few regenerative approaches exist for the treatment of injuries to adult dense connective tissues. Compared to fetal tissues, adult connective tissues are hypocellular and show limited healing after injury. We hypothesized that robust repair can occur in fetal tissues with an immature extracellular matrix (ECM) that is conducive to cell migration, and that this process fails in adults due to the biophysical barriers imposed by the mature ECM. Using the knee meniscus as a platform, we evaluated the evolving micromechanics and microstructure of fetal and adult tissues, and interrogated the interstitial migratory capacity of adult meniscal cells through fetal and adult tissue microenvironments with or without partial enzymatic digestion. To integrate our findings, a computational model was implemented to determine how changing biophysical parameters impact cell migration through these dense networks. Our results show that the micromechanics and microstructure of the adult meniscus ECM sterically hinder cell mobility, and that modulation of these ECM attributes via an exogenous matrix-degrading enzyme permits migration through this otherwise impenetrable network. By addressing the inherent limitations to repair imposed by the mature ECM, these studies may define new clinical strategies to promote repair of damaged dense connective tissues in adults.

Cartilage and bone cells do not participate in skeletal regeneration in Ambystoma mexicanum limbs.

PubMed

McCusker, Catherine D; Diaz-Castillo, Carlos; Sosnik, Julian; Q Phan, Anne; Gardiner, David M

2016-08-01

The Mexican Axolotl is one of the few tetrapod species that is capable of regenerating complete skeletal elements in injured adult limbs. Whether the skeleton (bone and cartilage) plays a role in the patterning and contribution to the skeletal regenerate is currently unresolved. We tested the induction of pattern formation, the effect on cell proliferation, and contributions of skeletal tissues (cartilage, bone, and periosteum) to the regenerating axolotl limb. We found that bone tissue grafts from transgenic donors expressing GFP fail to induce pattern formation and do not contribute to the newly regenerated skeleton. Periosteum tissue grafts, on the other hand, have both of these activities. These observations reveal that skeletal tissue does not contribute to the regeneration of skeletal elements; rather, these structures are patterned by and derived from cells of non-skeletal connective tissue origin. Copyright © 2016 Elsevier Inc. All rights reserved.

Evaluation of sample holders designed for long-lasting X-ray micro-tomographic scans of ex-vivo soft tissue samples

NASA Astrophysics Data System (ADS)

Dudak, J.; Zemlicka, J.; Krejci, F.; Karch, J.; Patzelt, M.; Zach, P.; Sykora, V.; Mrzilkova, J.

2016-03-01

X-ray microradiography and microtomography are imaging techniques with increasing applicability in the field of biomedical and preclinical research. Application of hybrid pixel detector Timepix enables to obtain very high contrast of low attenuating materials such as soft biological tissue. However X-ray imaging of ex-vivo soft tissue samples is a difficult task due to its structural instability. Ex-vivo biological tissue is prone to fast drying-out which is connected with undesired changes of sample size and shape producing later on artefacts within the tomographic reconstruction. In this work we present the optimization of our Timepix equipped micro-CT system aiming to maintain soft tissue sample in stable condition. Thanks to the suggested approach higher contrast of tomographic reconstructions can be achieved while also large samples that require detector scanning can be easily measured.

Invited review: mesenchymal progenitor cells in intramuscular connective tissue development.

PubMed

Miao, Z G; Zhang, L P; Fu, X; Yang, Q Y; Zhu, M J; Dodson, M V; Du, M

2016-01-01

The abundance and cross-linking of intramuscular connective tissue contributes to the background toughness of meat, and is thus undesirable. Connective tissue is mainly synthesized by intramuscular fibroblasts. Myocytes, adipocytes and fibroblasts are derived from a common pool of progenitor cells during the early embryonic development. It appears that multipotent mesenchymal stem cells first diverge into either myogenic or non-myogenic lineages; non-myogenic mesenchymal progenitors then develop into the stromal-vascular fraction of skeletal muscle wherein adipocytes, fibroblasts and derived mesenchymal progenitors reside. Because non-myogenic mesenchymal progenitors mainly undergo adipogenic or fibrogenic differentiation during muscle development, strengthening progenitor proliferation enhances the potential for both intramuscular adipogenesis and fibrogenesis, leading to the elevation of both marbling and connective tissue content in the resulting meat product. Furthermore, given the bipotent developmental potential of progenitor cells, enhancing their conversion to adipogenesis reduces fibrogenesis, which likely results in the overall improvement of marbling (more intramuscular adipocytes) and tenderness (less connective tissue) of meat. Fibrogenesis is mainly regulated by the transforming growth factor (TGF) β signaling pathway and its regulatory cascade. In addition, extracellular matrix, a part of the intramuscular connective tissue, provides a niche environment for regulating myogenic differentiation of satellite cells and muscle growth. Despite rapid progress, many questions remain in the role of extracellular matrix on muscle development, and factors determining the early differentiation of myogenic, adipogenic and fibrogenic cells, which warrant further studies.

WE-DE-202-02: Are Track Structure Simulations Truly Needed for Radiobiology at the Cellular and Tissue Levels?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stewart, R.

Radiation therapy for the treatment of cancer has been established as a highly precise and effective way to eradicate a localized region of diseased tissue. To achieve further significant gains in the therapeutic ratio, we need to move towards biologically optimized treatment planning. To achieve this goal, we need to understand how the radiation-type dependent patterns of induced energy depositions within the cell (physics) connect via molecular, cellular and tissue reactions to treatment outcome such as tumor control and undesirable effects on normal tissue. Several computational biology approaches have been developed connecting physics to biology. Monte Carlo simulations are themore » most accurate method to calculate physical dose distributions at the nanometer scale, however simulations at the DNA scale are slow and repair processes are generally not simulated. Alternative models that rely on the random formation of individual DNA lesions within one or two turns of the DNA have been shown to reproduce the clusters of DNA lesions, including single strand breaks (SSBs), double strand breaks (DSBs) without the need for detailed track structure simulations. Efficient computational simulations of initial DNA damage induction facilitate computational modeling of DNA repair and other molecular and cellular processes. Mechanistic, multiscale models provide a useful conceptual framework to test biological hypotheses and help connect fundamental information about track structure and dosimetry at the sub-cellular level to dose-response effects on larger scales. In this symposium we will learn about the current state of the art of computational approaches estimating radiation damage at the cellular and sub-cellular scale. How can understanding the physics interactions at the DNA level be used to predict biological outcome? We will discuss if and how such calculations are relevant to advance our understanding of radiation damage and its repair, or, if the underlying biological processes are too complex for a mechanistic approach. Can computer simulations be used to guide future biological research? We will debate the feasibility of explaining biology from a physicists’ perspective. Learning Objectives: Understand the potential applications and limitations of computational methods for dose-response modeling at the molecular, cellular and tissue levels Learn about mechanism of action underlying the induction, repair and biological processing of damage to DNA and other constituents Understand how effects and processes at one biological scale impact on biological processes and outcomes on other scales J. Schuemann, NCI/NIH grantsS. McMahon, Funding: European Commission FP7 (grant EC FP7 MC-IOF-623630)« less

Automatic segementation of histological structures in normal and neoplastic mammary gland tissue sections

NASA Astrophysics Data System (ADS)

Fernandez-Gonzalez, Rodrigo; Deschamps, Thomas; Idica, Adam; Malladi, Ravikanth; Ortiz de Solorzano, Carlos

2003-07-01

In this paper we present a scheme for real time segmentation of histological structures in microscopic images of normal and neoplastic mammary gland sections. Paraffin embedded or frozen tissue blocks are sliced, and sections are stained with hematoxylin and eosin (H&E). The sections are then imaged using conventional bright field microscopy. The background of the images is corrected by arithmetic manipulation using a "phantom." Then we use the fast marching method with a speed function that depends on the brightness gradient of the image to obtain a preliminary approximation to the boundaries of the structures of interest within a region of interest (ROI) of the entire section manually selected by the user. We use the result of the fast marching method as the initial condition for the level set motion equation. We run this last method for a few steps and obtain the final result of the segmentation. These results can be connected from section to section to build a three-dimensional reconstruction of the entire tissue block that we are studying.

Magnetic resonance imaging-three-dimensional printing technology fabricates customized scaffolds for brain tissue engineering

PubMed Central

Fu, Feng; Qin, Zhe; Xu, Chao; Chen, Xu-yi; Li, Rui-xin; Wang, Li-na; Peng, Ding-wei; Sun, Hong-tao; Tu, Yue; Chen, Chong; Zhang, Sai; Zhao, Ming-liang; Li, Xiao-hong

2017-01-01

Conventional fabrication methods lack the ability to control both macro- and micro-structures of generated scaffolds. Three-dimensional printing is a solid free-form fabrication method that provides novel ways to create customized scaffolds with high precision and accuracy. In this study, an electrically controlled cortical impactor was used to induce randomized brain tissue defects. The overall shape of scaffolds was designed using rat-specific anatomical data obtained from magnetic resonance imaging, and the internal structure was created by computer-aided design. As the result of limitations arising from insufficient resolution of the manufacturing process, we magnified the size of the cavity model prototype five-fold to successfully fabricate customized collagen-chitosan scaffolds using three-dimensional printing. Results demonstrated that scaffolds have three-dimensional porous structures, high porosity, highly specific surface areas, pore connectivity and good internal characteristics. Neural stem cells co-cultured with scaffolds showed good viability, indicating good biocompatibility and biodegradability. This technique may be a promising new strategy for regenerating complex damaged brain tissues, and helps pave the way toward personalized medicine. PMID:28553343

Morphological and molecular analysis of the collagen fibers in inflammatory process

NASA Astrophysics Data System (ADS)

de Carvalho, Luis Felipe das Chagas e. Silva; Alves, Mônica Ghislaine Oliveira; Soares, Carlos Alexandre; Almeida, Janete Dias; da Silva Martinho, Herculano

2011-07-01

Collagen makes up one third of the total protein in humans, being formed by the connection of three polypeptide chains arranged in a triple helix. This protein has fundamental importance in the formation of extracellular matrix of connective tissue. This study aimed to analyze the structural changes of collagen, which are resulting from inflammatory processes in oral mucosa, and to make the comparative analysis between the histopathology and the Raman spectra. The samples of tissues with inflammatory fibrous hyperplasia (IFH) and normal mucosa (NM) were evaluated by Raman Spectroscopy, hematoxylin-eosin and Massons trichrome stain. The histological analysis in both stains showed differences in collagen fibers, which was presented as thin fibers and arranged in parallel direction in NM and as collagen fibers are thick, mature and not organized, showing that these types of stain show morphological changes of collagen in IFH. The Raman Spectroscopy discriminate the groups of NM and IFH based on vibrational modes of proline, hydroxiproline and CH3, CH2. The histological stains only shows information from morphological data, and can be complemented by Raman spectra. This technique could demonstrate that inflammatory process caused some changes in collagen structure which is related to aminoacids such as proline and hidroxyproline.

Composition and structure of the pericellular environment. Physiological function and chemical composition of pericellular proteoglycan (an evolutionary view).

PubMed

Scott, J E

1975-07-17

Connective tissue cells exist in a meshwork of insoluble fibres, the interstices of which are filled with soluble, high molecular mass, anionic material of a predominantly carbohydrate nature. The interactions of fibres with the interfibrillar material are central to the discussion of connective tissue physiology. As with all soluble polymers, the interfibrillar polyanion tends to "swell' and the tangled mass of chains offers considerable resistance to penetration by the large insoluble fibres. The consequent pressure to "inflate' the fibrous network is important in giving elasticity to cartilage, transparency to cornea, etc. Branched structures (of proteoglycans) and straight-chain forms (of hyaluronate) are compared for their ability to fulfil these functions. Apart from their physical ("non-specific') roles proteoglycans and glycosaminoglycans are able to interact physicochemically with, for example, collagen in ways which show considerable specificity, and which presumably are important in the laying down of the fibrous network as well as in maintaining its mechanical integrity. It is proposed that the role played by radiation, particularly as mediated via the hydrated electron (eaq) was dominant in the pre- and post-biotic evolution of pericellular environments.

Acoustic properties of healthy and reconstructed cleft lip

NASA Astrophysics Data System (ADS)

Thijssen, Johan M.; van Hees, Nancy J.; Weijers, Gert G.; Huyskens, Rinske W.; Nillesen, Maartje; Katsaros, Christos; de Korte, Chris L.

2006-03-01

The feasibility of echographic imaging of the tissues in healthy lip and in reconstructed cleft lip and estimating the dimensions and the normalized echo level of these tissues is investigated. Echographic images of the upper lip were made with commercial medical ultrasound equipment, using a linear array transducer (7-11 MHz bandwidth) and a non-contact gel coupling. Tissue dimensions were measured by means of software calipers. Echo levels were calibrated and corrected for beam characteristics, gel path and tissue attenuation by using a tissue-mimicking phantom. At central position of philtrum, mean thickness (and standard deviation) of lip loose connective tissue layer, orbicularis oris muscle and dense connective layer was 4.0 (sd 0.1) mm, 2.3 (sd 0.7) mm, 2.2 (sd 0.7) mm, respectively, in healthy lip at rest. Mean (sd) echo level of muscle and dense connective tissue layer with respect to echo level of lip loose connective tissue layer was in relaxed condition: - 19.3 (sd 0.6) dB and - 10.7 (sd 4.0) dB, respectively. Echo level of loose connective tissue layer was +25.6 (sd 4.2) dB relative to phantom echo level obtained in the focus of the transducer. Color mode echo images were calculated, after adaptive filtering of the images, which show the tissues in separate colors and highlight the details of healthy lip and reconstructed cleft lip. Quantitative assessment of thickness and echo level of various lip tissues is feasible after proper calibration of the echographic equipment. Diagnostic potentials of the developed quantitative echographic techniques for non-invasive evaluation of the outcome of cleft lip reconstruction are promising.

Ectopic mineralization disorders of the extracellular matrix of connective tissue: molecular genetics and pathomechanisms of aberrant calcification.

PubMed

Li, Qiaoli; Jiang, Qiujie; Uitto, Jouni

2014-01-01

Ectopic mineralization of connective tissues is a complex process leading to deposition of calcium phosphate complexes in the extracellular matrix, particularly affecting the skin and the arterial blood vessels and common in age-associated disorders. A number of initiating and contributing metabolic and environmental factors are linked to aberrant mineralization in these diseases, making the identification of precise pathomechanistic pathways exceedingly difficult. However, there has been significant recent progress in understanding the ectopic mineralization processes through study of heritable single-gene disorders, which have allowed identification of discrete pathways and contributing factors leading to aberrant connective tissue mineralization. These studies have provided support for the concept of an intricate mineralization/anti-mineralization network present in peripheral connective tissues, providing a perspective to development of pharmacologic approaches to limit the phenotypic consequences of ectopic mineralization. This overview summarizes the current knowledge of ectopic heritable mineralization disorders, with accompanying animal models, focusing on pseudoxanthoma elasticum and generalized arterial calcification of infancy, two autosomal recessive diseases manifesting with extensive connective tissue mineralization in the skin and the cardiovascular system. © 2013.

[Pulmonary involvement in connective tissue disease].

PubMed

Bartosiewicz, Małgorzata

2016-01-01

The connective tissue diseases are a variable group of autoimmune mediated disorders characterized by multiorgan damage. Pulmonary complications are common, usually occur after the onset of joint symptoms, but can also be initially presenting complaint. The respiratory system may be involved in all its component: airways, vessels, parenchyma, pleura and respiratory muscles. Lung involvement is an increasing cause of morbidity and mortality in the connective tissue diseases. Clinical course is highly variable - can range from mild to rapidly progressive, some processes are reversible, while others are irreversible. Thus, the identification of reversible disease , and separately progressive disease, are important clinical issues. The frequency, clinical presentation, prognosis and responce to therapy are different, depending on the pattern of involvement as well as on specyfic diagnostic method used to identify it. High- resolution computed tompography plays an important role in identifying patients with respiratory involvement. Pulmonary function tests are a sensitive tool detecting interstitial lung disease. In this article, pulmonary lung involvement accompanying most frequently apperaing connective tissue diseases - rheumatoid arthritis, systemic sclerosis, lupus erythematosus, polymyositis/dermatomyositis, Sjögrens syndrome and mixed connective tissue disaese are reviewed.

Ectopic mineralization disorders of the extracellular matrix of connective tissue: Molecular genetics and pathomechanisms of aberrant calcification

PubMed Central

Li, Qiaoli; Jiang, Qiujie; Uitto, Jouni

2013-01-01

Ectopic mineralization of connective tissues is a complex process leading to deposition of calcium phosphate complexes in the extracellular matrix, particularly affecting the skin and the arterial blood vessels and common in age-associated disorders. A number of initiating and contributing metabolic and environmental factors are linked to aberrant mineralization in these diseases, making the identification of precise pathomechanistic pathways exceedingly difficult. However, there has been significant recent progress in understanding the ectopic mineralization processes through study of heritable single-gene disorders, which have allowed identification of discreet pathways and contributing factors leading to aberrant connective tissue mineralization. These studies have provided support for the concept of an intricate mineralization/anti-mineralization network present in peripheral connective tissues, providing a perspective to development of pharmacologic approaches to limit the phenotypic consequences of ectopic mineralization. This overview summarizes the current knowledge of ectopic heritable mineralization disorders, with accompanying animal models, focusing on pseudoxanthoma elasticum and generalized arterial calcification of infancy, two autosomal recessive diseases manifesting with extensive connective tissue mineralization in the skin and the cardiovascular system. PMID:23891698

Polarization spectrometry diagnostic of cervical pathological states of endometriosis

NASA Astrophysics Data System (ADS)

Yermolenko, S. B.; Peresunko, O. P.; Burkovets, D. N.

2018-01-01

The purpose of the study was to determine the histochemical and laser criteria for diagnosis of background, precancerous and endometrial cancer by the state of the cervical canal wall. The given data on the state of connective tissue in the endocervix can distinguish three differential prognostic possibilities: - prediction of the condition of the connective tissue of the endocervix of the normal endometrium without the possibility of differentiating the phases of the ovarian cycle; - prediction of the endocervix endotracheal connective tissue state of the endometrium as a separate process; - prediction for the condition of the connective tissue of the endocervix of the processes of expressed proliferation of the typical (glandular hyperplasia and glandular polyps) or atypical (adenocarcinoma) glandular first endometrial epithelial differentiation without the possibility of these processes among them. The stroke-scrape of the epithelium of the cervical canal (endocervix) allows the condition of the connective tissue to diagnose the processes of pronounced proliferation of the typical (hyperplasia, polyp) and atypical (adenocarcinoma) epithelium of the endometrium without the possibility of differentiating these processes among themselves.

Connective tissue integrity is lost in vitamin B-6-deficient chicks

NASA Technical Reports Server (NTRS)

Masse, P. G.; Yamauchi, M.; Mahuren, J. D.; Coburn, S. P.; Muniz, O. E.; Howell, D. S.

1995-01-01

The objective of the present investigation was to characterize further the connective tissue disorder produced by pyridoxine (vitamin B-6) deficiency, as previously evidenced by electron microscopy. Following the second post-natal week, fast growing male chicks were deprived of pyridoxine for a 1-mo period. Six weeks post-natally, blood concentrations in the experimental deficiency group had declined to deficiency levels as registered by low concentrations of pyridoxal phosphate (coenzyme form) in erythrocytes, but did not reach levels associated with neurological symptoms. Light microscopic study showed abnormalities in the extracellular matrix of the connective tissues. Collagen cross-links and the aldehyde contents were not significantly lower in cartilage and tendon collagens of vitamin B-6-deficient animals than in age-matched controls; also, their proteoglycan degrading protease and collagenase activities measured in articular cartilages were not greater. Thus, proteolysis was an unlikely alternative mechanism to account for the loss of connective tissue integrity. These results point to the need for further investigation into adhesive properties of collagen associated proteoglycans or other proteins in vitamin B-6-deficient connective tissue.

The application of quantitative cytochemistry to the study of diseases of the connective tissues.

PubMed

Henderson, B

1983-01-01

The connective tissues are a complex organisation of tissues, cells and intercellular materials spread throughout the body and are subject to a large number of diseases. Such complexity makes the study of the metabolism of the connective tissues in health and more particularly in disease states difficult if one uses conventional biochemical methodology. Fortunately the techniques of quantitative cytochemistry, as developed in recent years, have made it possible to study the metabolism of even such complex and refractory connective tissues as bone. Using properly validated assays of enzyme activity in unfixed sections from various tissues a number of the diseases of the connective tissues have been studied. For example the synovia from patients with rheumatoid arthritis and related conditions have been studied using these techniques and marked alterations in the metabolism of the synovial lining cell population of this tissue have been demonstrated. These alterations in metabolism are believed to be related to the destruction of cartilage and bone found in such diseases. Investigations of the metabolism of the chondrocytes of articular cartilage in a strain of mice which spontaneously develops osteoarthritis has revealed a lack of certain key enzymes of carbohydrate metabolism in precisely those areas where degradation of the matrix of articular cartilage begins suggesting a causal relationship between these events. These same techniques have been used to study the cellular kinetics and metabolism of the dermis and epidermis in the disfiguring disease, psoriasis. The metabolism of healing bone fractures, the diagnosis and treatment of the mucopolysaccharidoses and the metabolic effects of currently used anti-inflammatory and anti-rheumatic drugs have also been examined. Perhaps the most exciting aspect of these studies has been the development and use of the technique of the cytochemical bioassay (CBA) to study hormonally mediated diseases of the connective tissues. Such studies have recently shed new light on the molecular lesion in pseudohypoparathyroidism. Though still in their relative infancy the studies described in this review show the potential inherent in the use of quantitative cytochemistry for the study of diseases of the connective tissues.

Histological assessment of the triangular fibrocartilage complex.

PubMed

Semisch, M; Hagert, E; Garcia-Elias, M; Lluch, A; Rein, S

2016-06-01

The morphological structure of the seven components of triangular fibrocartilage complexes of 11 cadaver wrists of elderly people was assessed microscopically, after staining with Hematoxylin-Eosin and Elastica van Gieson. The articular disc consisted of tight interlaced fibrocartilage without blood vessels except in its ulnar part. Volar and dorsal radioulnar ligaments showed densely parallel collagen bundles. The subsheath of the extensor carpi ulnaris muscle, the ulnotriquetral and ulnolunate ligament showed mainly mixed tight and loose parallel tissue. The ulnolunate ligament contained tighter parallel collagen bundles and clearly less elastic fibres than the ulnotriquetral ligament. The ulnocarpal meniscoid had an irregular morphological composition and loose connective tissue predominated. The structure of the articular disc indicates a buffering function. The tight structure of radioulnar and ulnolunate ligaments reflects a central stabilizing role, whereas the ulnotriquetral ligament and ulnocarpal meniscoid have less stabilizing functions. © The Author(s) 2015.

Central nervous system tissue heterotopia of the nose: case report and review of the literature

PubMed Central

Altissimi, G; Ascani, S; Falcetti, S; Cazzato, C; Bravi, I

2009-01-01

Summary The Authors present a case of heterotopic central nervous system tissue observed in an 81-year-old male in the form of an ethmoidal polyp. A review of the literature indicates that this is a rare condition characterised by a connective tissue lesion with astrocytic and oligodendrocytic glial cells, which may be located outside the nasal pyramid in some cases and inside the nasal cavity in others. The most important diagnostic aspect involves differentiating these from meningoencephalocele, which maintains an anatomical connection with central nervous system tissue. Contrast-enhanced imaging is essential for diagnosis, as in cases of heterotopic central nervous system tissue, it will demonstrate that there are no connections with intra-cranial tissue. Endoscopic excision is the treatment of choice. PMID:20161881

Structural and functional bases of laser-microvessels interaction

NASA Astrophysics Data System (ADS)

Kozlov, Valentine I.; Terman, Oleg A.; Builin, Vitalij; Lebedeva, Natalia A.; Samoilov, Nickolai

1993-07-01

Structural and functional microcirculatory changes in tissues and organs (muscles, liver, derma, epinephros, brain cortex) under various dosages and powers of laser irradiation in the red (633 nm) and near infrared (890 nm) spectrum regions have been studied in experiments and clinic. In case of nonsensitized tissues the `photoactivation' range of power densities and doses of laser irradiation has been established. We have identified a short-term reaction of microvessels and a long-term reaction (adaptation). The former consists of intensification of microcirculation and metabolism rise in parenchymatous cells; the latter is connected with neoangiogenesis acceleration. The intensification of the blood microcirculation includes a dilation of microvessels of all orders, an amplification of arteriolar vasomotions and an opening of `reserved' capillaries. Data on the structural reconstruction of myocytes and endotheliocytes have shown that the high differential parenchymatous cells and its membrane structures are sensitive to low energy laser irradiation and, on the other hand, under low energy laser irradiation there is an activation of synthetic processes in the cells. Thus, during the laser-tissue interaction in such complex system as human organism the microcirculation plays the key role among the other systems.

Simulation of ultrasonic pulse propagation, distortion, and attenuation in the human chest wall.

PubMed

Mast, T D; Hinkelman, L M; Metlay, L A; Orr, M J; Waag, R C

1999-12-01

A finite-difference time-domain model for ultrasonic pulse propagation through soft tissue has been extended to incorporate absorption effects as well as longitudinal-wave propagation in cartilage and bone. This extended model has been used to simulate ultrasonic propagation through anatomically detailed representations of chest wall structure. The inhomogeneous chest wall tissue is represented by two-dimensional maps determined by staining chest wall cross sections to distinguish between tissue types, digitally scanning the stained cross sections, and mapping each pixel of the scanned images to fat, muscle, connective tissue, cartilage, or bone. Each pixel of the tissue map is then assigned a sound speed, density, and absorption value determined from published measurements and assumed to be representative of the local tissue type. Computational results for energy level fluctuations and arrival time fluctuations show qualitative agreement with measurements performed on the same specimens, but show significantly less waveform distortion than measurements. Visualization of simulated tissue-ultrasound interactions in the chest wall shows possible mechanisms for image aberration in echocardiography, including effects associated with reflection and diffraction caused by rib structures. A comparison of distortion effects for varying pulse center frequencies shows that, for soft tissue paths through the chest wall, energy level and waveform distortion increase markedly with rising ultrasonic frequency and that arrival-time fluctuations increase to a lesser degree.

Three dimensional microstructural network of elastin, collagen, and cells in Achilles tendons.

PubMed

Pang, Xin; Wu, Jian-Ping; Allison, Garry T; Xu, Jiake; Rubenson, Jonas; Zheng, Ming-Hao; Lloyd, David G; Gardiner, Bruce; Wang, Allan; Kirk, Thomas Brett

2017-06-01

Similar to most biological tissues, the biomechanical, and functional characteristics of the Achilles tendon are closely related to its composition and microstructure. It is commonly reported that type I collagen is the predominant component of tendons and is mainly responsible for the tissue's function. Although elastin has been found in varying proportions in other connective tissues, previous studies report that tendons contain very small quantities of elastin. However, the morphology and the microstructural relationship among the elastic fibres, collagen, and cells in tendon tissue have not been well examined. We hypothesize the elastic fibres, as another fibrillar component in the extracellular matrix, have a unique role in mechanical function and microstructural arrangement in Achilles tendons. It has been shown that elastic fibres present a close connection with the tenocytes. The close relationship of the three components has been revealed as a distinct, integrated and complex microstructural network. Notably, a "spiral" structure within fibril bundles in Achilles tendons was observed in some samples in specialized regions. This study substantiates the hierarchical system of the spatial microstructure of tendon, including the mapping of collagen, elastin and tenocytes, with 3-dimensional confocal images. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1203-1214, 2017. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Scaffold architecture and fibrin gels promote meniscal cell proliferation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pawelec, K. M., E-mail: pawelec.km@gmail.com, E-mail: jw626@cam.ac.uk; Best, S. M.; Cameron, R. E.

2015-01-01

Stability of the knee relies on the meniscus, a complex connective tissue with poor healing ability. Current meniscal tissue engineering is inadequate, as the signals for increasing meniscal cell proliferation have not been established. In this study, collagen scaffold structure, isotropic or aligned, and fibrin gel addition were tested. Metabolic activity was promoted by fibrin addition. Cellular proliferation, however, was significantly increased by both aligned architectures and fibrin addition. None of the constructs impaired collagen type I production or triggered adverse inflammatory responses. It was demonstrated that both fibrin gel addition and optimized scaffold architecture effectively promote meniscal cell proliferation.

[Oxygen-dependent processes in the blood cells from children with arterial hypertension concomitant with biliary dyskinesia].

PubMed

Mikashinovich, Z I; Nagornaia, G Iu; Kovalenko, T D; Zvereva, E A

2011-02-01

Age individuality is characterized by an imbalance of the molecular mechanisms of antioxidant defense in adolescents with arterial hypertension and biliary dyskinesia, as documented by an enzyme imbalance of the first line of antioxidant defense and H2O, accumulation, by a substantial increase in glutathione peroxidase activity, and by inhibition of the activity of glutathione-dependent enzymes. The considerable rise of 2,3-diphosphoglycerate suggests tissue hypoxia. With this, enhanced neutrophil elastase activity causes damage to the structural components of vascular wall connective tissue, resulting in the development of endothelial dysfunction.

[Klinefelter's syndrome associated with mixed connective tissue disease (Sharp's syndrome) and thrombophilia with postthrombotic syndrome].

PubMed

Kasten, Robert; Pfirrmann, Gudrun; Voigtländer, Volker

2005-08-01

A 43-year-old male with eunuchoid body proportions and a history of deep venous thromboses in the right leg presented with recurrent ulcers in the right perimalleolar region for 6 years. Karyotyping revealed a 47 XXY Klinefelter's syndrome, while serologic testing showed protein S deficiency, hyperhomocysteinemia and positive lupus anticoagulant. He also had mixed connective tissue disease (Sharp's syndrome) with acrosclerosis, proximal finger edema, Raynaud's phenomenon, and high titers of ANA and U1-RNP-antibodies, as well as osteoporosis. There is evidence that patients with Klinefelter's syndrome are prone to develop connective tissue diseases and thrombophilia as a result of low androgen levels. Substitution of testosterone in Klinefelter's syndrome can have a favorable therapeutic effect on the associated connective tissue disease, thrombophilia and osteoporosis.

Functional joint regeneration is achieved using reintegration mechanism in Xenopus laevis

PubMed Central

Yamada, Shigehito

2016-01-01

Abstract A functional joint requires integration of multiple tissues: the apposing skeletal elements should form an interlocking structure, and muscles should insert into skeletal tissues via tendons across the joint. Whereas newts can regenerate functional joints after amputation, Xenopus laevis regenerates a cartilaginous rod without joints, a “spike.” Previously we reported that the reintegration mechanism between the remaining and regenerated tissues has a significant effect on regenerating joint morphogenesis during elbow joint regeneration in newt. Based on this insight into the importance of reintegration, we amputated frogs’ limbs at the elbow joint and found that frogs could regenerate a functional elbow joint between the remaining tissues and regenerated spike. During regeneration, the regenerating cartilage was partially connected to the remaining articular cartilage to reform the interlocking structure of the elbow joint at the proximal end of the spike. Furthermore, the muscles of the remaining part inserted into the regenerated spike cartilage via tendons. This study might open up an avenue for analyzing molecular and cellular mechanisms of joint regeneration using Xenopus. PMID:27499877

Connective tissue graft as a biological barrier for guided tissue regeneration in intrabony defects: a histological study in dogs.

PubMed

Ribeiro, Fernando Salimon; Pontes, Ana Emília Farias; Zuza, Elizangela Partata; da Silva, Vanessa Camila; Lia, Raphael Carlos Comelli; Marcantonio Junior, Elcio

2015-06-01

The use of the autogenous periosteal graft as biological barrier has been proposed for periodontal regeneration. The aim of this study was to evaluate the histometric findings of the subepithelial connective tissue graft as barrier in intrabony defects compared to a bioabsorbable membrane. Three-walled intrabony defects were created surgically in the mesial aspect of the right and left maxillary canines in five healthy mongrel dogs. The defects were chronified, and two types of barriers were randomly carried out for guided tissue regeneration in a split-mouth design: the test group with a subepithelial connective tissue graft and the control group with a bioabsorbable membrane. The specimens were processed for histometric analyses of the epithelium (E), connective tissue (CT), newly formed cementum (NC), new bone (NB), and total newly formed tissues (NFT). The test side showed smaller mean of NC (3.6 ± 1.2), NB (2.1 ± 0.7), and NFT (7.7 ± 0.8) than the control group (NC 7.3 ± 0.5; NB 5.3 ± 1.3; NFT 10.1 ± 2.2; P < 0.05). No statistically significant differences were verified for E (test 3.1 ± 2.0; control 2.8 ± 2.1; P > 0.05) and CT (test 2.5 ± 1.1; control 2.0 ± 0.5; P > 0.05) between groups. The bioabsorbable membrane was more effective in maintaining the space for periodontal regeneration than periosteal connective graft when used as barrier. The bioabsorbable membrane showed more favorable regenerative results in intrabony defects in dogs than the subepithelial connective tissue graft as biological barrier.

[Morphological characteristics of kidneys connective tissue of mature fetuses and newborns from mothers, whose pregnancy was complicated by preeclampsia of varying degrees of severity].

PubMed

Sorokina, Iryna V; Myroshnychenko, Mykhailo S; Kapustnyk, Nataliia V; Khramova, Tetyana O; Dehtiarova, Oksana V; Danylchenko, Svitlana I

2018-01-01

Introduction: The kidneys connective tissue condition in the antenatal period affects the formation of tissues and it changes with the development of various general pathological processes in this organ. The aim of the study was to identify the morphological features of kidneys connective tissue of fetuses and newborns from mothers whose pregnancy was complicated by preeclampsia of varying degrees of severity. Materials and methods: The material of the study was the tissue of kidneys of mature fetuses and newborns from mothers with physiological pregnancy (28 cases), as well as from mothers whose pregnancy was complicated by preeclampsia of varying degrees of severity (78 cases). Immunohistochemical study was performed by an indirect Coons method according to M. Brosman's technique using monoclonal antibodies to collagen type I, III and IV. Results: The kidneys connective tissue of fetuses and newborns developing under the maternal preeclampsia conditions is characterized by the qualitative and quantitative changes that indicate the development of sclerotic processes in this organ, the severity of which increase with the age and with the increase of the maternal preeclampsia severity. Qualitative changes are characterized by an increase of the fibrous component, thickening of the bundles of connective tissue fibers, and a decrease in the distance between them. Quantitative changes are characterized by a pronounced predominance of collagen fibers over elastic fibers, almost total absence in some field of view elastic fibers and the violation of the content of collagen type I, III and IV. Conclusion: Maternal preeclampsia underlies the development of qualitative and quantitative changes in kidneys connective tissue of fetuses and newborns, which as a result will lead to disruption of the functions of these organs in such children.

Multimodal and Multi-tissue Measures of Connectivity Revealed by Joint Independent Component Analysis.

PubMed

Franco, Alexandre R; Ling, Josef; Caprihan, Arvind; Calhoun, Vince D; Jung, Rex E; Heileman, Gregory L; Mayer, Andrew R

2008-12-01

The human brain functions as an efficient system where signals arising from gray matter are transported via white matter tracts to other regions of the brain to facilitate human behavior. However, with a few exceptions, functional and structural neuroimaging data are typically optimized to maximize the quantification of signals arising from a single source. For example, functional magnetic resonance imaging (FMRI) is typically used as an index of gray matter functioning whereas diffusion tensor imaging (DTI) is typically used to determine white matter properties. While it is likely that these signals arising from different tissue sources contain complementary information, the signal processing algorithms necessary for the fusion of neuroimaging data across imaging modalities are still in a nascent stage. In the current paper we present a data-driven method for combining measures of functional connectivity arising from gray matter sources (FMRI resting state data) with different measures of white matter connectivity (DTI). Specifically, a joint independent component analysis (J-ICA) was used to combine these measures of functional connectivity following intensive signal processing and feature extraction within each of the individual modalities. Our results indicate that one of the most predominantly used measures of functional connectivity (activity in the default mode network) is highly dependent on the integrity of white matter connections between the two hemispheres (corpus callosum) and within the cingulate bundles. Importantly, the discovery of this complex relationship of connectivity was entirely facilitated by the signal processing and fusion techniques presented herein and could not have been revealed through separate analyses of both data types as is typically performed in the majority of neuroimaging experiments. We conclude by discussing future applications of this technique to other areas of neuroimaging and examining potential limitations of the methods.

Keloids and Hypertrophic Scars

MedlinePlus

... to the skin both skin cells and connective tissue cells (fibroblasts) begin multiplying to repair the damage. A scar is made up of 'connective tissue', gristle-like fibers deposited in the skin by ...

Anatomy and Histology of an Epicanthal Fold.

PubMed

Park, Jae Woo; Hwang, Kun

2016-06-01

The aim of this study is to elucidate the precise anatomical and histological detail of the epicanthal fold.Thirty-two hemifaces of 16 Korean adult cadavers were used in this study (30 hemifaces with an epicanthal fold, 2 without an epicanthal fold). In 2 patients who had an epicanthoplasty, the epicanthal folds were sampled.In a dissection, the periorbital skin and subcutaneous tissues were removed and the epicanthal fold was observed in relation to each part of the orbicularis oculi muscle. Specimens including the epicanthal fold were embeddedin in paraffin, sectioned at 10 um, and stained with Hematoxylin-Eosin. The horizontal section in the level of the paplebral fissure was made and the prepared slides were observed under a light microscope.In the specimens without an epicanthal fold, no connection between the upper preseptal muscle and the lower preseptal muscle was found. In the specimens with an epicanthal fold, a connection of the upper preseptal muscle to the lower preseptal muscle was observed. It was present in all 15 hemifaces (100%). There was no connection between the pretarsal muscles. In a horizontal section, the epicanthal fold was composed of 3 compartments: an outer skin lining, a core structure, and an innerskin lining. The core structure was mainly composed of muscular fibers and fibrotic tissue and they were intermingled.Surgeons should be aware of the anatomical details of an epicanthal fold. In removing or reconstructing an epicanthal fold, the fibromuscular core band should also be removed or reconstructed.

Clinical evaluation of subepithelial connective tissue graft and guided tissue regeneration for treatment of Miller’s class 1 gingival recession (comparative, split mouth, six months study)

PubMed Central

Bhavsar, Neeta-V.; Dulani, Kirti; Trivedi, Rahul

2014-01-01

Objectives: The present study aims to clinically compare and evaluate subepithelial connective tissue graft and the GTR based root coverage in treatment of Miller’s Class I gingival recession. Study Design: 30 patients with at least one pair of Miller’s Class I gingival recession were treated either with Subepithelial connective tissue graft (Group A) or Guided tissue regeneration (Group B). Clinical parameters monitored included recession RD, width of keratinized gingiva (KG), probing depth (PD), clinical attachment level (CAL), attached gingiva (AG), residual probing depth (RPD) and % of Root coverage(%RC). Measurements were taken at baseline, three months and six months. A standard surgical procedure was used for both Group A and Group B. Data were recorded and statistical analysis was done for both intergroup and intragroup. Results: At end of six months % RC obtained were 84.47% (Group A) and 81.67% (Group B). Both treatments resulted in statistically significant improvement in clinical parameters. When compared, no statistically significant difference was found between both groups except in RPD, where it was significantly greater in Group A. Conclusions: GTR technique has advantages over subepithelial connective tissue graft for shallow Miller’s Class I defects and this procedure can be used to avoid patient discomfort and reduce treatment time. Key words:Collagen membrane, comparative split mouth study, gingival recession, subepithelial connective tissue graft, guided tissue regeneration (GTR). PMID:25136420

Heterogeneous structure and surface tension effects on mechanical response in pulmonary acinus: A finite element analysis.

PubMed

Koshiyama, Kenichiro; Nishimoto, Keisuke; Ii, Satoshi; Sera, Toshihiro; Wada, Shigeo

2018-01-20

The pulmonary acinus is a dead-end microstructure that consists of ducts and alveoli. High-resolution micro-CT imaging has recently provided detailed anatomical information of a complete in vivo acinus, but relating its mechanical response with its detailed acinar structure remains challenging. This study aimed to investigate the mechanical response of acinar tissue in a whole acinus for static inflation using computational approaches. We performed finite element analysis of a whole acinus for static inflation. The acinar structure model was generated based on micro-CT images of an intact acinus. A continuum mechanics model of the lung parenchyma was used for acinar tissue material model, and surface tension effects were explicitly included. An anisotropic mechanical field analysis based on a stretch tensor was combined with a curvature-based local structure analysis. The airspace of the acinus exhibited nonspherical deformation as a result of the anisotropic deformation of acinar tissue. A strain hotspot occurred at the ridge-shaped region caused by a rod-like deformation of acinar tissue on the ridge. The local structure becomes bowl-shaped for inflation and, without surface tension effects, the surface of the bowl-shaped region primarily experiences isotropic deformation. Surface tension effects suppressed the increase in airspace volume and inner surface area, while facilitating anisotropic deformation on the alveolar surface. In the lungs, the heterogeneous acinar structure and surface tension induce anisotropic deformation at the acinar and alveolar scales. Further research is needed on structural variation of acini, inter-acini connectivity, or dynamic behavior to understand multiscale lung mechanics. Copyright © 2018 Elsevier Ltd. All rights reserved.

Connective tissue responses to some heavy metals. II. Lead: histology and ultrastructure.

PubMed Central

Ellender, G.; Ham, K. N.

1987-01-01

Lead loaded ion exchange resin beads implanted into the loose connective tissue of the rat pinna induced local lesions which differed widely from those of the control (sodium loaded) beads (Ellender & Ham 1987). These lesions were characterized by changes in the granulation tissue and the approximating connective tissue. Granulation tissue contained mononuclear phagocytes in various guises, and some cells with intranuclear inclusion bodies. The matrix of the granulation tissue contained collagen fibrils having a wide range of diameters suggestive of altered collagen biosynthesis. Foci of collagen mineralization occurred in zones of combined trauma and lead impregnation. Once mineralized they became enveloped by giant cells and epithelioid cells. Lead in damaged tissues is thought to modify the protective mechanism of calcification inhibition and the biosynthesis of the matrix. Images Fig. 6 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11 Fig. 12 Fig. 13 PMID:3040063

Probing multi-scale self-similarity of tissue structures using light scattering spectroscopy: prospects in pre-cancer detection

NASA Astrophysics Data System (ADS)

Chatterjee, Subhasri; Das, Nandan K.; Kumar, Satish; Mohapatra, Sonali; Pradhan, Asima; Panigrahi, Prasanta K.; Ghosh, Nirmalya

2013-02-01

Multi-resolution analysis on the spatial refractive index inhomogeneities in the connective tissue regions of human cervix reveals clear signature of multifractality. We have thus developed an inverse analysis strategy for extraction and quantification of the multifractality of spatial refractive index fluctuations from the recorded light scattering signal. The method is based on Fourier domain pre-processing of light scattering data using Born approximation, and its subsequent analysis through Multifractal Detrended Fluctuation Analysis model. The method has been validated on several mono- and multi-fractal scattering objects whose self-similar properties are user controlled and known a-priori. Following successful validation, this approach has initially been explored for differentiating between different grades of precancerous human cervical tissues.

Marfan Syndrome

MedlinePlus

Marfan syndrome is a disorder that affects connective tissue. Connective tissues are proteins that support skin, bones, blood vessels, ... A problem with the fibrillin gene causes Marfan syndrome. Marfan syndrome can be mild to severe, and ...

Uterine Prolapse

MedlinePlus

... during bowel movements Family history of weakness in connective tissue Being Hispanic or white Complications Uterine prolapse is ... You might experience: Anterior prolapse (cystocele). Weakness of connective tissue separating the bladder and vagina may cause the ...

The Effect Of microbial Mats In The Decay Of Anurans With Implications For Understanding Taphonomic Processes In The Fossil Record

PubMed Central

Iniesto, M.; Villalba, I.; Buscalioni, A. D.; Guerrero, M. C.; López-Archilla, A. I.

2017-01-01

The pattern and sequence of the decomposition of the Pipidae African dwarf frog (Hymenochirus boettgeri) is tracked in an experiment with microbial mats in order to explore soft tissue preservation over three years. Frog decay in microbial mats is preceded by rapid entombment (25–30 days) and mediated by the formation of a sarcophagus, which is built by a complex microbial community. The frog carcasses maintained a variety of soft tissues for years. Labile organic structures show greater durability within the mat, cells maintain their general shape (bone marrow cells and adipocytes), and muscles and connective tissues (adipose and fibrous tendons) exhibit their original organic structures. In addition, other soft tissues are promptly mineralized (day 540) in a Ca-rich carbonate phase (encephalic tectum) or enriched in sulphur residues (integumentary system). The result is coherent with a bias in soft-tissue preservation, as some tissues are more likely to be conserved than others. The outcomes support observations of exceptionally preserved fossil anurans (adults and tadpoles). Decomposition in mats shows singular conditions of pH and dissolved oxygen. Mineralization processes could be more diverse than in simple heterotrophic biofilms, opening new taphonomic processes that have yet to be explored. PMID:28338095

Evidence of structurally continuous collagen fibrils in tendons.

PubMed

Svensson, Rene B; Herchenhan, Andreas; Starborg, Tobias; Larsen, Michael; Kadler, Karl E; Qvortrup, Klaus; Magnusson, S Peter

2017-03-01

Tendons transmit muscle-generated force through an extracellular matrix of aligned collagen fibrils. The force applied by the muscle at one end of a microscopic fibril has to be transmitted through the macroscopic length of the tendon by mechanisms that are poorly understood. A key element in this structure-function relationship is the collagen fibril length. During embryogenesis short fibrils are produced but they grow rapidly with maturation. There is some controversy regarding fibril length in adult tendon, with mechanical data generally supporting discontinuity while structural investigations favor continuity. This study initially set out to trace the full length of individual fibrils in adult human tendons, using serial block face-scanning electron microscopy. But even with this advanced technique the required length could not be covered. Instead a statistical approach was used on a large volume of fibrils in shorter image stacks. Only a single end was observed after tracking 67.5mm of combined fibril lengths, in support of fibril continuity. To shed more light on this observation, the full length of a short tendon (mouse stapedius, 125μm) was investigated and continuity of individual fibrils was confirmed. In light of these results, possible mechanisms that could reconcile the opposing findings on fibril continuity are discussed. Connective tissues hold all parts of the body together and are mostly constructed from thin threads of the protein collagen (called fibrils). Connective tissues provide mechanical strength and one of the most demanding tissues in this regard are tendons, which transmit the forces generated by muscles. The length of the collagen fibrils is essential to the mechanical strength and to the type of damage the tissue may experience (slippage of short fibrils or breakage of longer ones). This in turn is important for understanding the repair processes after such damage occurs. Currently the issue of fibril length is contentious, but this study provides evidence that the fibrils are extremely long and likely continuous. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Deep nuclear invaginations are linked to cytoskeletal filaments – integrated bioimaging of epithelial cells in 3D culture

PubMed Central

Inman, Jamie L.; Wojcik, Michal; Robertson, Claire; Tsai, Wen-Ting; Huang, Haina; Bruni-Cardoso, Alexandre; López, Claudia S.; Bissell, Mina J.; Xu, Ke

2017-01-01

ABSTRACT The importance of context in regulation of gene expression is now an accepted principle; yet the mechanism by which the microenvironment communicates with the nucleus and chromatin in healthy tissues is poorly understood. A functional role for nuclear and cytoskeletal architecture is suggested by the phenotypic differences observed between epithelial and mesenchymal cells. Capitalizing on recent advances in cryogenic techniques, volume electron microscopy and super-resolution light microscopy, we studied human mammary epithelial cells in three-dimensional (3D) cultures forming growth-arrested acini. Intriguingly, we found deep nuclear invaginations and tunnels traversing the nucleus, encasing cytoskeletal actin and/or intermediate filaments, which connect to the outer nuclear envelope. The cytoskeleton is also connected both to other cells through desmosome adhesion complexes and to the extracellular matrix through hemidesmosomes. This finding supports a physical and/or mechanical link from the desmosomes and hemidesmosomes to the nucleus, which had previously been hypothesized but now is visualized for the first time. These unique structures, including the nuclear invaginations and the cytoskeletal connectivity to the cell nucleus, are consistent with a dynamic reciprocity between the nucleus and the outside of epithelial cells and tissues. PMID:27505896

Deep nuclear invaginations are linked to cytoskeletal filaments – integrated bioimaging of epithelial cells in 3D culture

DOE PAGES

Jorgens, Danielle M.; Inman, Jamie L.; Wojcik, Michal; ...

2016-08-05

The importance of context in regulation of gene expression is now an accepted principle; yet the mechanism by which the microenvironment communicates with the nucleus and chromatin in healthy tissues is poorly understood. A functional role for nuclear and cytoskeletal architecture is suggested by the phenotypic differences observed between epithelial and mesenchymal cells. Capitalizing on recent advances in cryogenic techniques, volume electron microscopy and super-resolution light microscopy, we studied human mammary epithelial cells in three-dimensional (3D) cultures forming growtharrested acini. Intriguingly, we found deep nuclear invaginations and tunnels traversing the nucleus, encasing cytoskeletal actin and/or intermediate filaments, which connect tomore » the outer nuclear envelope. Also, the cytoskeleton is connected both to other cells through desmosome adhesion complexes and to the extracellular matrix through hemidesmosomes. This finding supports a physical and/or mechanical link from the desmosomes and hemidesmosomes to the nucleus, which had previously been hypothesized but now is visualized for the first time. These unique structures, including the nuclear invaginations and the cytoskeletal connectivity to the cell nucleus, are consistent with a dynamic reciprocity between the nucleus and the outside of epithelial cells and tissues.« less

Isolation, separation, and characterization of epithelial and connective cells from rat palate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Terranova, Victor Paul

1979-01-01

Epithelial and connective tissue cells were isolated from rat palate by sequential collagenase, hyaluronidase and trypsin digestion of the extracellular matrix. Differences between the two populations were noted with respect to total cell protein, total cell water, proline uptake and incorporation, percent collagen synthesized, effects of parathyroid hormone, metabolism of D-valine and cell density. Basal epithelial cells were subsequently separated from the heterogeneous epithelial cell population on shallow linear density gradients by velocity centrifugation. The type of collagen synthesized by the basal epithelial cells was compared to the type of collagen synthesized by the connective tissue cells by means ofmore » labeled amino acid incorporation ratios. Cells isolated from the epithelial and connective tissue were compared. From these studies it can be concluded that epithelial and connective tissue cells can be isolated from rat palate as viable and distinct populations with respect to the biochemical parameters examined. Furthermore, subpopulations can be separated and biochemically characterized.« less

Stromal cell-based immunotherapy in transplantation.

PubMed

Charles, Ronald; Lu, Lina; Qian, Shiguang; Fung, John J

2011-12-01

Organs are composed of parenchymal cells that characterize organ function and nonparenchymal cells that are composed of cells in transit, as well as tissue connective tissue, also referred to as tissue stromal cells. It was originally thought that these tissue stromal cells provided only structural and functional support for parenchymal cells and were relatively inert. However, we have come to realize that tissue stromal cells, not restricted to in the thymus and lymphoid organs, also play an active role in modulating the immune system and its response to antigens. The recognition of these elements and the elucidation of their mechanisms of action have provided valuable insight into peripheral immune regulation. Extrapolation of these principles may allow us to utilize their potential for clinical application. In this article, we will summarize a number of tissue stromal elements/cell types that have been shown to induce hyporesponsiveness to transplants. We will also discuss the mechanisms by which these stromal cells create a tolerogenic environment, which in turn results in long-term allograft survival.

Rod-Shaped Neural Units for Aligned 3D Neural Network Connection.

PubMed

Kato-Negishi, Midori; Onoe, Hiroaki; Ito, Akane; Takeuchi, Shoji

2017-08-01

This paper proposes neural tissue units with aligned nerve fibers (called rod-shaped neural units) that connect neural networks with aligned neurons. To make the proposed units, 3D fiber-shaped neural tissues covered with a calcium alginate hydrogel layer are prepared with a microfluidic system and are cut in an accurate and reproducible manner. These units have aligned nerve fibers inside the hydrogel layer and connectable points on both ends. By connecting the units with a poly(dimethylsiloxane) guide, 3D neural tissues can be constructed and maintained for more than two weeks of culture. In addition, neural networks can be formed between the different neural units via synaptic connections. Experimental results indicate that the proposed rod-shaped neural units are effective tools for the construction of spatially complex connections with aligned nerve fibers in vitro. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Heritable Disorders of Connective Tissue

MedlinePlus

... skin. Epidermolysis bullosa affects the skin, causing blisters. Marfan syndrome can affect the heart, blood vessels, lungs, eyes, ... Disorders of Connective Tissue, Questions and Answers about Marfan Syndrome, Questions and Answers about Marfan Syndrome, Easy-to- ...

Mechanical, structural, and dynamical modifications of cholesterol exposed porcine aortic elastin.

PubMed

Bilici, Kubra; Morgan, Steven W; Silverstein, Moshe C; Wang, Yunjie; Sun, Hyung Jin; Zhang, Yanhang; Boutis, Gregory S

2016-11-01

Elastin is a protein of the extracellular matrix that contributes significantly to the elasticity of connective tissues. In this study, we examine dynamical and structural modifications of aortic elastin exposed to cholesterol by NMR spectroscopic and relaxation methodologies. Macroscopic measurements are also presented and reveal that cholesterol treatment may cause a decrease in the stiffness of tissue. 2 H NMR relaxation techniques revealed differences between the relative populations of water that correlate with the swelling of the tissue following cholesterol exposure. 13 C magic-angle-spinning NMR spectroscopy and relaxation methods indicate that cholesterol treated aortic elastin is more mobile than control samples. Molecular dynamics simulations on a short elastin repeat VPGVG in the presence of cholesterol are used to investigate the energetic and entropic contributions to the retractive force, in comparison to the same peptide in water. Peptide stiffness is observed to reduce following cholesterol exposure due to a decrease in the entropic force. Copyright © 2016 Elsevier B.V. All rights reserved.

Mechanical, Structural, and Dynamical Modifications of Cholesterol Exposed Porcine Aortic Elastin

PubMed Central

Bilici, Kubra; Morgan, Steven W.; Silverstein, Moshe C.; Wang, Yunjie; Sun, Hyung Jin; Zhang, Katherine; Boutis, Gregory S.

2016-01-01

Elastin is a protein of the extracellular matrix that contributes significantly to the elasticity of connective tissues. In this study, we examine dynamical and structural modifications of aortic elastin exposed to cholesterol by NMR spectroscopic and relaxation methodologies. Macroscopic measurements are also presented and reveal that cholesterol treatment may cause a decrease in the stiffness of tissue. 2H NMR relaxation techniques revealed differences between the relative populations of water that correlate with the swelling of the tissue following cholesterol exposure. 13C magic-angle-spinning NMR spectroscopy and relaxation methods indicate that cholesterol treated aortic elastin appears more mobile than control samples. Molecular dynamics simulations on a short elastin repeat VPGVG in the presence of cholesterol are used to investigate the energetic and entropic contributions to the retractive force, in comparison to the same peptide in water. Peptide stiffness is observed to reduce following cholesterol exposure due to a decrease in the entropic force. PMID:27648754

Determination of collagen fibril structure and orientation in connective tissues by X-ray diffraction

NASA Astrophysics Data System (ADS)

Wilkinson, S. J.; Hukins, D. W. L.

1999-08-01

Elastic scattering of X-rays can provide the following information on the fibrous protein collagen: its molecular structure, the axial arrangement of rod-like collagen molecules in a fibril, the lateral arrangement of molecules within a fibril, and the orientation of fibrils within a biological tissue. The first part of the paper reviews the principles involved in deducing this information. The second part describes a new computer program for measuring the equatorial intensity distribution, that provides information on the lateral arrangement of molecules within a fibril, and the angular distribution of the equatorial peaks that provides information on the orientation of fibrils. Orientation of fibrils within a tissue is quantified by the orientation distribution function, g( φ), which represents the probability of finding a fibril oriented between φ and φ+ δφ. The application of the program is illustrated by measurement of g( φ) for the collagen fibrils in demineralised cortical bone from cow tibia.

Histological analysis of the structural composition of ankle ligaments.

PubMed

Rein, Susanne; Hagert, Elisabet; Schneiders, Wolfgang; Fieguth, Armin; Zwipp, Hans

2015-02-01

Various ankle ligaments have different structural composition. The aim of this study was to analyze the morphological structure of ankle ligaments to further understand their function in ankle stability. One hundred forty ligaments from 10 fresh-frozen cadaver ankle joints were dissected: the calcaneofibular, anterior, and posterior talofibular ligaments; the inferior extensor retinaculum, the talocalcaneal oblique ligament, the canalis tarsi ligament; the deltoid ligament; and the anterior tibiofibular ligament. Hematoxylin-eosin and Elastica van Gieson stains were used for determination of tissue morphology. Three different morphological compositions were identified: dense, mixed, and interlaced compositions. Densely packed ligaments, characterized by parallel bundles of collagen, were primarily seen in the lateral region, the canalis tarsi, and the anterior tibiofibular ligaments. Ligaments with mixed tight and loose parallel bundles of collagenous connective tissue were mainly found in the inferior extensor retinaculum and talocalcaneal oblique ligament. Densely packed and fiber-rich interlacing collagen was primarily seen in the areas of ligament insertion into bone of the deltoid ligament. Ligaments of the lateral region, the canalis tarsi, and the anterior tibiofibular ligaments have tightly packed, parallel collagen bundles and thus can resist high tensile forces. The mixed tight and loose, parallel oriented collagenous connective tissue of the inferior extensor retinaculum and the talocalcaneal oblique ligament support the dynamic positioning of the foot on the ground. The interlacing collagen bundles seen at the insertion of the deltoid ligament suggest that these insertion areas are susceptible to tension in a multitude of directions. The morphology and mechanical properties of ankle ligaments may provide an understanding of their response to the loads to which they are subjected. © The Author(s) 2015.

Stiparin: a glycoprotein from sea cucumber dermis that aggregates collagen fibrils.

PubMed

Trotter, J A; Lyons-Levy, G; Luna, D; Koob, T J; Keene, D R; Atkinson, M A

1996-07-01

The interactions between collagen fibrils in many echinoderm connective tissues are rapidly altered by the secretions of resident neurosecretory cells. Recent evidence has suggested that a secreted protein is responsible for the interactions that lead to an increase in tissue stiffness (Trotter and Koob, 1995). Structurally intact collagen fibrils have been isolated from such a connective tissue- the dermis of the sea cucumber Cucumaria frondosa- and used in an assay in vitro to identify a protein that binds to them and causes them to aggregate. This protein has been purified by anion-exchange and molecular sieve chromatography. It is eluted from a MonoQ column at approximately 0.55 M NaCl. Its isoelectric point is 5.2. It elutes from a Superose-6 column in a position corresponding to a molecule with a Stokes radius of 11.5 nm. Its native molecular weight estimated from sedimentation equilibrium analysis under non-denaturing conditions is 375,000, and its monomer molecular weight, estimated by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate, is approximately 350,000. Sedimentation velocity measurements indicated for the native molecule a sedimentation coefficient of 11 x 10(-13)s, a diffusion coefficient of 3.274 x 10(-7) cm2s-1, and a frictional ratio of 1.95, which corresponds to a prolate ellipsoid of revolution with an axial ratio of 19. The highly asymmetric structure suggested by the above correlated well with the images obtained by transmission electron microscopy following rotary shadowing, which revealed a flexible structure approximately 125 nm long. Based on its ability to aggregate collagen fibrils, this protein has been named "stiparin," from the Latin stipare, "to pack together."

Serial sectioning for examination of photoreceptor cell architecture by focused ion beam technology

PubMed Central

Mustafi, Debarshi; Avishai, Amir; Avishai, Nanthawan; Engel, Andreas; Heuer, Arthur; Palczewski, Krzysztof

2011-01-01

Structurally deciphering complex neural networks requires technology with sufficient resolution to allow visualization of single cells and their intimate surrounding connections. Scanning electron microscopy (SEM), coupled with serial ion ablation (SIA) technology, presents a new avenue to study these networks. SIA allows ion ablation to remove nanometer sections of tissue for SEM imaging, resulting in serial section data collection for three-dimensional reconstruction. Here we highlight a method for preparing retinal tissues for imaging of photoreceptors by SIA-SEM technology. We show that this technique can be used to visualize whole rod photoreceptors and the internal disc elements from wild-type (wt) mice. The distance parameters of the discs and photoreceptors are in good agreement with previous work with other methods. Moreover, we show that large planes of retinal tissue can be imaged at high resolution to display the packing of normal rods. Finally, SIA-SEM imaging of retinal tissue from a mouse model (Nrl−/−) with phenotypic changes akin to the human disease enhanced S-cone syndrome (ESCS) revealed a structural profile of overall photoreceptor ultrastructure and internal elements that accompany this disease. Overall, this work presents a new method to study photoreceptor cells at high structural resolution that has a broad applicability to the visual neuroscience field. PMID:21439323

Control of cell growth on 3D-printed cell culture platforms for tissue engineering.

PubMed

Tan, Zhikai; Liu, Tong; Zhong, Juchang; Yang, Yikun; Tan, Weihong

2017-12-01

Biocompatible tissue growth has excellent prospects for tissue engineering. These tissues are built over scaffolds, which can influence aspects such as cell adhesion, proliferation rate, morphology, and differentiation. However, the ideal 3D biological structure has not been developed yet. Here, we applied the electro-hydrodynamic jet (E-jet) 3D printing technology using poly-(lactic-co-glycolic acid, PLGA) solution to print varied culture platforms for engineered tissue structures. The effects of different parameters (electrical voltage, plotting speed, and needle sizes) on the outcome were investigated. We compared the biological compatibility of the 3D printed culture platforms with that of random fibers. Finally, we used the 3D-printed PLGA platforms to culture fibroblasts, the main cellular components of loose connective tissue. The results show that the E-jet printed platforms could guide and improve cell growth. These highly aligned fibers were able to support cellular alignment and proliferation. Cell angle was consistent with the direction of the fibers, and cells cultured on these fibers showed a much faster migration, potentially enhancing wound healing performance. Thus, the potential of this technology for 3D biological printing is large. This process can be used to grow biological scaffolds for the engineering of tissues. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 3281-3292, 2017. © 2017 Wiley Periodicals, Inc.

Convergent Findings of Altered Functional and Structural Brain Connectivity in Individuals with High Functioning Autism: A Multimodal MRI Study

PubMed Central

Samson, Andrea C.; Kirsch, Valerie; Blautzik, Janusch; Grothe, Michel; Erat, Okan; Hegenloh, Michael; Coates, Ute; Reiser, Maximilian F.; Hennig-Fast, Kristina; Meindl, Thomas

2013-01-01

Brain tissue changes in autism spectrum disorders seem to be rather subtle and widespread than anatomically distinct. Therefore a multimodal, whole brain imaging technique appears to be an appropriate approach to investigate whether alterations in white and gray matter integrity relate to consistent changes in functional resting state connectivity in individuals with high functioning autism (HFA). We applied diffusion tensor imaging (DTI), voxel-based morphometry (VBM) and resting state functional connectivity magnetic resonance imaging (fcMRI) to assess differences in brain structure and function between 12 individuals with HFA (mean age 35.5, SD 11.4, 9 male) and 12 healthy controls (mean age 33.3, SD 9.0, 8 male). Psychological measures of empathy and emotionality were obtained and correlated with the most significant DTI, VBM and fcMRI findings. We found three regions of convergent structural and functional differences between HFA participants and controls. The right temporo-parietal junction area and the left frontal lobe showed decreased fractional anisotropy (FA) values along with decreased functional connectivity and a trend towards decreased gray matter volume. The bilateral superior temporal gyrus displayed significantly decreased functional connectivity that was accompanied by the strongest trend of gray matter volume decrease in the temporal lobe of HFA individuals. FA decrease in the right temporo-parietal region was correlated with psychological measurements of decreased emotionality. In conclusion, our results indicate common sites of structural and functional alterations in higher order association cortex areas and may therefore provide multimodal imaging support to the long-standing hypothesis of autism as a disorder of impaired higher-order multisensory integration. PMID:23825652

[The effect of neoplastic disease and systemic disease of connective tissue on the occurrence of dehiscence laparotomy].

PubMed

Paunović, Milorad

2013-01-01

Dehiscence after laparotomy is one of the major complications of laparotomy. This is a partial or complete wound with disruption and evisceratio abdominal organs and require urgent reintervention. The aim of this study was to determine the impact of neoplastic disease and systemic disease of connective tissue on the occurrence of dehiscence laparotomy. A prospective study were included 612 patients operated at the Clinic for General Surgery in Nis in the period from January 2009 to December 2010. The effect of neoplastic disease and the presence of systemic disease of connective tissue on the occurrence of dehiscence laparotomy. Results are displayed numerically and in percentages. Of the total 24 patients with dehiscence laparotomy, 15 patients were male or 62.5% and 9 female patients, or 37.5%. There was a statistically significant association between dehiscence laparotomy and neoplastic diseases (c2 = 42,196; p < 0.01). There was no statistically significant association between dehiscence laparo-tomy and systemic disease of connective tissue (c2 = 0,028; p > 0.05). In patients with neoplastic diseases dehis-cence laparotomy is common, and in patients suffering from systemic disease of connective tissue dehiscence laparotomy occurs less frequently.

Aberrant immune response with consequent vascular and connective tissue remodeling - causal to scleroderma and associated syndromes such as Raynaud phenomenon and other fibrosing syndromes?

PubMed

Durmus, Nedim; Park, Sung-Hyun; Reibman, Joan; Grunig, Gabriele

2016-11-01

Scleroderma and other autoimmune-induced connective tissue diseases are characterized by dysfunctions in the immune system, connective tissue and the vasculature. We are focusing on systemic sclerosis (SSc)-associated pulmonary hypertension, which remains a leading cause of death with only a 50-60% of 2-year survival rate. Much research and translational efforts have been directed at understanding the immune response that causes SSc and the networked interactions with the connective tissue and the vasculature. One of the unexpected findings was that in some cases the pathogenic immune response in SSc resembles the immune response to helminth parasites. During coevolution, means of communication were developed which protect the host from over-colonization with parasites and which protect the parasite from excessive host responses. One explanation for the geographically clustered occurrence of SSc is that environmental exposures combined with genetic predisposition turn on triggers of molecular and cellular modules that were once initiated by parasites. Future research is needed to further understand the parasite-derived signals that dampen the host response. Therapeutic helminth infection or treatment with parasite-derived response modifiers could be promising new management tools for autoimmune connective tissue diseases.

Histological evidence for a dynamic dental battery in hadrosaurid dinosaurs.

PubMed

Bramble, Katherine; LeBlanc, Aaron R H; Lamoureux, Denis O; Wosik, Mateusz; Currie, Philip J

2017-11-17

The first histological study of an entire hadrosaurid dental battery provides a comprehensive look at tooth movement within this complex structure. Previous studies have focused on isolated teeth, or in-situ batteries, but this is the first study to examine an entire dental battery of any dinosaur. The absence of direct tooth-to-tooth contact across the entire battery and a unique arrangement of the dental tissues in hadrosaurids led us to compare their teeth with the ever-growing incisors of mammals. The similarity in the distributions of tissues along the incisor, coupled with continuous eruption, make for helpful comparisons to hadrosaurid teeth. The mammalian ever-growing incisor can be used as a model to extrapolate the soft tissue connections and eruptive mechanisms within the hadrosaurid dental battery. Serial sections across the adult dental battery reveal signs of gradual ontogenetic tooth migration. Extensive remodeling of the alveolar septa and the anteroposterior displacement of successive generations of teeth highlight the gradual migration of tooth generations within the battery. These eruptive and ontogenetic tooth movements would not be possible without a ligamentous connection between successive teeth and the jaws, underscoring the dynamic nature of one of the most unique and complex dental systems in vertebrate history.

Void space inside the developing seed of Brassica napus and the modelling of its function

PubMed Central

Verboven, Pieter; Herremans, Els; Borisjuk, Ljudmilla; Helfen, Lukas; Ho, Quang Tri; Tschiersch, Henning; Fuchs, Johannes; Nicolaï, Bart M; Rolletschek, Hardy

2013-01-01

The developing seed essentially relies on external oxygen to fuel aerobic respiration, but it is currently unknown how oxygen diffuses into and within the seed, which structural pathways are used and what finally limits gas exchange. By applying synchrotron X-ray computed tomography to developing oilseed rape seeds we uncovered void spaces, and analysed their three-dimensional assembly. Both the testa and the hypocotyl are well endowed with void space, but in the cotyledons, spaces were small and poorly inter-connected. In silico modelling revealed a three orders of magnitude range in oxygen diffusivity from tissue to tissue, and identified major barriers to gas exchange. The oxygen pool stored in the voids is consumed about once per minute. The function of the void space was related to the tissue-specific distribution of storage oils, storage protein and starch, as well as oxygen, water, sugars, amino acids and the level of respiratory activity, analysed using a combination of magnetic resonance imaging, specific oxygen sensors, laser micro-dissection, biochemical and histological methods. We conclude that the size and inter-connectivity of void spaces are major determinants of gas exchange potential, and locally affect the respiratory activity of a developing seed. PMID:23692271

The versatile subepithelial connective tissue graft: a literature update.

PubMed

Karthikeyan, B V; Khanna, Divya; Chowdhary, Kamedh Yashawant; Prabhuji, M Lv

2016-01-01

Harmony between hard and soft tissue morphologies is essential for form, function, and a good esthetic outlook. Replacement grafts for correction of soft tissue defects around the teeth have become important to periodontal plastic and implant surgical procedures. Among a multitude of surgical techniques and graft materials reported in literature, the subepithelial connective tissue graft (SCTG) has gained wide popularity and acceptance. The purpose of this article is to acquaint clinicians with the current understanding of the versatile SCTG. Key factors associated with graft harvesting as well as applications, limitations, and complications of SCTGs are discussed. This connective tissue has shown excellent short- and long-term stability, is easily available, and is economical to use. The SCTG should be considered as an alternative in all periodontal reconstruction surgeries.

Cell density signal protein suitable for treatment of connective tissue injuries and defects

DOEpatents

Schwarz, Richard I.

2002-08-13

Identification, isolation and partial sequencing of a cell density protein produced by fibroblastic cells. The cell density signal protein comprising a 14 amino acid peptide or a fragment, variant, mutant or analog thereof, the deduced cDNA sequence from the 14 amino acid peptide, a recombinant protein, protein and peptide-specific antibodies, and the use of the peptide and peptide-specific antibodies as therapeutic agents for regulation of cell differentiation and proliferation. A method for treatment and repair of connective tissue and tendon injuries, collagen deficiency, and connective tissue defects.

[Connective tissue dysplasia in patients with celiac desease as a problem of violation of adaptation reserve islands of the body].

PubMed

Tkachenko, E; Oreshko, L S; Soloveva, E A; Shabanova, A A; Zhuravleva, M S

2015-01-01

Clinically significant dysplasia of connective tissue in patients with celiac disease is often responsible for various visceral disorders. Different disturbances of motor and evacuation functions are often determined in this patients (gastroesophageal reflux, duodenogastral reflux, spastic and hyperkinetic dyskinesia). The clinical course of the celiac disease, associated with connective tissue dysplasia, is characterized by asthenovegetative syndrome, reduced tolerance to physical activity, general weakness, fatigue and emotional instability. These data should be considered in choosing a treatment.

Non-marfan idiopathic medionecrosis (cystic medial necrosis) presenting with multiple visceral artery aneurysms and diffuse connective tissue fragility: Two brothers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kubota, Jun; Tsunemura, Mami; Amano, Shigeko

1997-05-15

Two brothers with multiple visceral artery aneurysms or dilatations and diffuse connective tissue fragility who did not have clinical features of Marfan syndrome are reported. One presented with retroperitoneal hemorrhage during angiography, and idiopathic medionecrosis was proved by resection of the aneurysms. These cases belong to the heterogeneous group of Marfan syndrome. The angiographical features (multiple dilation of visceral arteries) suggests fragility of connective tissue and is predictive of hazards during and after a catheterization and operation.

Irradiation by pulsed Nd:YAG laser induces the production of extracellular matrix molecules by cells of the connective tissues: a tool for tissue repair

NASA Astrophysics Data System (ADS)

Monici, Monica; Basile, Venere; Cialdai, Francesca; Romano, Giovanni; Fusi, Franco; Conti, Antonio

2008-04-01

Many studies demonstrated that mechanical stress is a key factor for tissue homeostasis, while unloading induce loss of mass and impairment of function. Because of their physiological function, muscle, connective tissue, bone and cartilage dynamically interact with mechanical and gravitational stress, modifying their properties through the continuous modification of their composition. Indeed, it is known that mechanical stress increases the production of extracellular matrix (ECM) components by cells, but the mechanotransduction mechanisms and the optimal loading conditions required for an optimal tissue homeostasis are still unknown. Considering the importance of cell activation and ECM production in tissue regeneration, a proper use of mechanical stimulation could be a powerful tool in tissue repair and tissue engineering. Studies exploring advanced modalities for supplying mechanical stimuli are needed to increase our knowledge on mechanobiology and to develop effective clinical applications. Here we describe the effect of photomechanical stress, supplied by a pulsed Nd:YAG laser on ECM production by cells of connective tissues. Cell morphology, production of ECM molecules (collagens, fibronectin, mucopolysaccharides), cell adhesion and cell energy metabolism have been studied by using immunofluorescence and autofluorescence microscopy. The results show that photomechanical stress induces cytoskeleton remodelling, redistribution of membrane integrins, increase in production of ECM molecules. These results could be of consequence for developing clinical protocols for the treatment of connective tissue dideases by pulsed Nd:YAG laser.

Treatment of gingival recession defects with xenogenic collagen matrix: a histologic report.

PubMed

Camelo, Marcelo; Nevins, Myron; Nevins, Marc L; Schupbach, Peter; Kim, David M

2012-04-01

The connective tissue graft (CTG) in conjunction with a coronally advanced flap is still regarded as the gold standard treatment for gingival recession defects. Increased surgical morbidity as well as limited tissue availability continues to spur interest in alternatives to the CTG. The current case report examines a porcine-derived, double-layer collagen matrix as an alternative to the CTG in managing Miller Class I and II recession defects. A long junctional epithelial attachment as well as connective tissue adhesion were noted when collagen matrix was used in conjunction with a coronally advanced flap in recession treatment protocols. The results suggest that it is possible to obtain root coverage without harvesting connective tissue.

Numerical modeling of fluid and oxygen exchanges through microcirculation for the assessment of microcirculation alterations caused by type 2 diabetes.

PubMed

Tang, Yuanliang; He, Ying

2018-05-01

Type 2 diabetes mellitus (DM2) is frequently accompanied by microcirculation complications, including structural and functional alterations, which may have serious effects on substance exchanges between blood and interstitial tissue and the health of organs. In this paper, we aim to study the influence of microcirculation alterations in DM2 patients on fluid and oxygen exchanges through a model analysis. A fluid flow and oxygen transport model were developed by considering the interplay between blood in capillary network and interstitial tissue. The two regions were separately represented by 1D network model and 3D volume model, and the immersed boundary method (IBM) was adopted to solve fluid and mass transfer between these two regions. By using the model, the steady flow field and the distributions of oxygen in capillary network and surrounding tissue were firstly simulated. In the interstitial volume, fluid pressure and oxygen tension decreased with the increase of distance from the network; in the network, oxygen tension in blood plasma dropped from 100 mm Hg at the entrance to about 40 mm Hg at the exit. We further tested several structural and functional disorders related to diabetic pathological conditions. Simulated results show that the impaired connectivity of the network could result in poor robustness in maintaining blood flow and perfused surface; under high fluid permeability conditions of capillary walls, the pressure gradient was much larger around the capillary bed, and this alteration led to a saturation level of the interstitial pressure when lymphatic flow drainage can't work effectively; the variations in network connectivity and permeability of capillary wall also had unfavorable influence on oxygen distributions in interstitial tissue. In addition, when the oxygen releasing capacity of hemoglobin was confined by glycosylated hemoglobin (HbA1) in the case of diabetes, the plasma could not be complemented with adequate oxygen and thus the hypoxic tissue range will be extended. This study illustrates that when microcirculation disturbances, including the structure of capillary network, the wall osmosis property and the capacity of blood binding oxygen occur in DM2, some negative impacts are raised on microvascular hemodynamics and metabolism circumstance of interstitial tissue. Copyright © 2018 Elsevier Inc. All rights reserved.

Phosphaturic mesenchymal tumour-mixed connective tissue variant without oncogenic osteomalacia.

PubMed

Winters, R; Bihlmeyer, S; McCahill, L; Cooper, K

2009-08-01

Phosphaturic mesenchymal tumour-mixed connective tissue variant is a rare tumour classically associated with oncogenic osteomalacia. This report describes two patients with this distinct tumour type but with no evidence of the paraneoplastic syndrome.

Parvovirus B19 infection in an adult presenting with connective tissue disease-like symptoms: a report of the clinical and histological findings.

PubMed

Liles, J E; Shalin, S C; White, B A; Trigg, L B; Kaley, J R

2017-06-15

Parvovirus B19 infections in adults are usually associated with nonspecific and mild symptoms. However, cases presenting with a lupus-like syndrome have been described, leading to the hypothesis that parvovirus infection can induce connective tissue disease. Various histopathologic features of cutaneous manifestations of parvovirus have been reported, including features which overlap with those of connective tissue disease. Herein, we discuss an unusual case of Parvovirus  B19 infection in a middle-aged woman. The biopsy results showed granulomatous vasculitis and were consistent with the previously described superantigen id reaction. This case demonstrates that infectious causes should be considered in the differential diagnosis for granulomatous vasculitis and clinicopathologic correlation is required for accurate diagnosis. We also provide a review of the literature highlighting the possible role of parvovirus in induction of a connective tissue disease-like presentation.

Biomechanical properties of the thoracic aorta in Marfan patients

PubMed Central

Sulejmani, Fatiesa; Pokutta-Paskaleva, Anastassia; Ziganshin, Bulat; Leshnower, Bradley; Iannucci, Glen; Elefteriades, John

2017-01-01

Background Marfan syndrome (MFS), a genetic disorder of the connective tissue, has been strongly linked to dilation of the thoracic aorta, among other cardiovascular complications. As a result, MFS patients frequently suffer from aortic dissection and rupture, contributing to the high rate of mortality and morbidity among MFS patients. Despite the significant effort devoted to the investigation of mechanical and structural properties of aneurysmal tissue, studies on Marfan aneurysmal biomechanics are scarce. Ex vivo mechanical characterization of MFS aneurysmal tissue can provide a better insight into tissue strength outside the physiologic loading range and serve as a basis for improved risk assessment and failure prediction. Methods The mechanical and microstructural properties of MFS aneurysmal thoracic aorta (MFS, n=15, 39.5±3.91 years), non-MFS aneurysmal thoracic aorta (TAA, n=8, 52.8±4.9 years), healthy human thoracic aorta (HH, n=8, 75.4±6.1 years), and porcine thoracic aorta (n=10) are investigated. Planar biaxial tensile testing and uniaxial failure testing were utilized to characterize the mechanical and failure properties of the tissue, respectively. Verhoeff-Van Gieson (VVG) and PicroSirius Red stains were utilized to visualize the elastin and collagen fiber architecture, respectively. Results MFS tissue was found to have age-dependent but diameter-independent mechanical, structural, and morphological properties, also showing extensive elastin fiber degradation. Non-MFS thoracic aneurysmal aorta was thicker and stiffer than age-matched MFS tissue. Moreover, non-MFS thoracic aneurysmal mechanics resembled closely the mechanics of older healthy human tissue. Younger MFS tissue (<40 years) exhibited similar mechanical and structural properties to aged porcine tissue. Conclusions Both age and aneurysmal presence were found to be factors associated with increased stiffness in aortic tissue, and aortic diameter was not a significant determinant of mechanical property deterioration. Additionally, the presence of MFS was found to induce stiffening of the thoracic aorta, although not to the extent of the non-MFS aneurysm. PMID:29270373

Cell Connections by Tunneling Nanotubes: Effects of Mitochondrial Trafficking on Target Cell Metabolism, Homeostasis, and Response to Therapy

PubMed Central

2017-01-01

Intercellular communications play a major role in tissue homeostasis and responses to external cues. Novel structures for this communication have recently been described. These tunneling nanotubes (TNTs) consist of thin-extended membrane protrusions that connect cells together. TNTs allow the cell-to-cell transfer of various cellular components, including proteins, RNAs, viruses, and organelles, such as mitochondria. Mesenchymal stem cells (MSCs) are both naturally present and recruited to many different tissues where their interaction with resident cells via secreted factors has been largely documented. Their immunosuppressive and repairing capacities constitute the basis for many current clinical trials. MSCs recruited to the tumor microenvironment also play an important role in tumor progression and resistance to therapy. MSCs are now the focus of intense scrutiny due to their capacity to form TNTs and transfer mitochondria to target cells, either in normal physiological or in pathological conditions, leading to changes in cell energy metabolism and functions, as described in this review. PMID:28659978

Three-dimensional histology: tools and application to quantitative assessment of cell-type distribution in rabbit heart

PubMed Central

Burton, Rebecca A.B.; Lee, Peter; Casero, Ramón; Garny, Alan; Siedlecka, Urszula; Schneider, Jürgen E.; Kohl, Peter; Grau, Vicente

2014-01-01

Aims Cardiac histo-anatomical organization is a major determinant of function. Changes in tissue structure are a relevant factor in normal and disease development, and form targets of therapeutic interventions. The purpose of this study was to test tools aimed to allow quantitative assessment of cell-type distribution from large histology and magnetic resonance imaging- (MRI) based datasets. Methods and results Rabbit heart fixation during cardioplegic arrest and MRI were followed by serial sectioning of the whole heart and light-microscopic imaging of trichrome-stained tissue. Segmentation techniques developed specifically for this project were applied to segment myocardial tissue in the MRI and histology datasets. In addition, histology slices were segmented into myocytes, connective tissue, and undefined. A bounding surface, containing the whole heart, was established for both MRI and histology. Volumes contained in the bounding surface (called ‘anatomical volume’), as well as that identified as containing any of the above tissue categories (called ‘morphological volume’), were calculated. The anatomical volume was 7.8 cm3 in MRI, and this reduced to 4.9 cm3 after histological processing, representing an ‘anatomical’ shrinkage by 37.2%. The morphological volume decreased by 48% between MRI and histology, highlighting the presence of additional tissue-level shrinkage (e.g. an increase in interstitial cleft space). The ratio of pixels classified as containing myocytes to pixels identified as non-myocytes was roughly 6:1 (61.6 vs. 9.8%; the remaining fraction of 28.6% was ‘undefined’). Conclusion Qualitative and quantitative differentiation between myocytes and connective tissue, using state-of-the-art high-resolution serial histology techniques, allows identification of cell-type distribution in whole-heart datasets. Comparison with MRI illustrates a pronounced reduction in anatomical and morphological volumes during histology processing. PMID:25362175

THE LOCALIZATION OF HOMOLGOUS PLASMA PROTEINS IN THE TISSUES OF YOUNG HUMAN BEINGS AS DEMONSTRATED WITH FLUORESCENT ANTIBODIES

PubMed Central

Gitlin, David; Landing, Benjamin H.; Whipple, Ann

1953-01-01

Employing fluorescent antibodies for the detection of homologous plasma proteins in tissue sections, the distribution of plasma albumin, γ-globulin, β-lipoprotein, β1-metal-combining globulin, and fibrinogen has been studied in the tissues of infants and children. Plasma albumin, γ-globulin, and β1-metal-combining globulin were found in many cells and particularly cell nuclei, connective tissues and interstitial spaces, lymphatics, and blood vessels. β-Lipoprotein was found mostly in the nuclei of all cell types while fibrinogen was restricted largely to the lymphatic and vascular channels, connective tissues and the interstitial spaces. The widespread distribution of these plasma proteins in cells and connective tissues indicates the magnitude of the extravascular plasma protein pool which is in equilibrium with circulating plasma. Unfortunately, these results do not permit accurate localization of the sites of production of these plasma proteins, but do give some idea of their intimate relationship to the tissues. PMID:13022871

Prediction of brain-computer interface aptitude from individual brain structure.

PubMed

Halder, S; Varkuti, B; Bogdan, M; Kübler, A; Rosenstiel, W; Sitaram, R; Birbaumer, N

2013-01-01

Brain-computer interface (BCI) provide a non-muscular communication channel for patients with impairments of the motor system. A significant number of BCI users is unable to obtain voluntary control of a BCI-system in proper time. This makes methods that can be used to determine the aptitude of a user necessary. We hypothesized that integrity and connectivity of involved white matter connections may serve as a predictor of individual BCI-performance. Therefore, we analyzed structural data from anatomical scans and DTI of motor imagery BCI-users differentiated into high and low BCI-aptitude groups based on their overall performance. Using a machine learning classification method we identified discriminating structural brain trait features and correlated the best features with a continuous measure of individual BCI-performance. Prediction of the aptitude group of each participant was possible with near perfect accuracy (one error). Tissue volumetric analysis yielded only poor classification results. In contrast, the structural integrity and myelination quality of deep white matter structures such as the Corpus Callosum, Cingulum, and Superior Fronto-Occipital Fascicle were positively correlated with individual BCI-performance. This confirms that structural brain traits contribute to individual performance in BCI use.

Prediction of brain-computer interface aptitude from individual brain structure

PubMed Central

Halder, S.; Varkuti, B.; Bogdan, M.; Kübler, A.; Rosenstiel, W.; Sitaram, R.; Birbaumer, N.

2013-01-01

Objective: Brain-computer interface (BCI) provide a non-muscular communication channel for patients with impairments of the motor system. A significant number of BCI users is unable to obtain voluntary control of a BCI-system in proper time. This makes methods that can be used to determine the aptitude of a user necessary. Methods: We hypothesized that integrity and connectivity of involved white matter connections may serve as a predictor of individual BCI-performance. Therefore, we analyzed structural data from anatomical scans and DTI of motor imagery BCI-users differentiated into high and low BCI-aptitude groups based on their overall performance. Results: Using a machine learning classification method we identified discriminating structural brain trait features and correlated the best features with a continuous measure of individual BCI-performance. Prediction of the aptitude group of each participant was possible with near perfect accuracy (one error). Conclusions: Tissue volumetric analysis yielded only poor classification results. In contrast, the structural integrity and myelination quality of deep white matter structures such as the Corpus Callosum, Cingulum, and Superior Fronto-Occipital Fascicle were positively correlated with individual BCI-performance. Significance: This confirms that structural brain traits contribute to individual performance in BCI use. PMID:23565083

A New Hybrid Viscoelastic Soft Tissue Model based on Meshless Method for Haptic Surgical Simulation

PubMed Central

Bao, Yidong; Wu, Dongmei; Yan, Zhiyuan; Du, Zhijiang

2013-01-01

This paper proposes a hybrid soft tissue model that consists of a multilayer structure and many spheres for surgical simulation system based on meshless. To improve accuracy of the model, tension is added to the three-parameter viscoelastic structure that connects the two spheres. By using haptic device, the three-parameter viscoelastic model (TPM) produces accurate deformationand also has better stress-strain, stress relaxation and creep properties. Stress relaxation and creep formulas have been obtained by mathematical formula derivation. Comparing with the experimental results of the real pig liver which were reported by Evren et al. and Amy et al., the curve lines of stress-strain, stress relaxation and creep of TPM are close to the experimental data of the real liver. Simulated results show that TPM has better real-time, stability and accuracy. PMID:24339837

Bone tissue formation in extraction sockets from sites with advanced periodontal disease: a histomorphometric study in humans.

PubMed

Ahn, Jae-Jin; Shin, Hong-In

2008-01-01

To investigate postextraction bone formation over time in both diseased and healthy sockets. Core specimens of healing tissues following tooth extraction were obtained at the time of implant placement in patients treated between October 2005 and December 2007. A disease group and a control group were classified according to socket examination at the time of extraction. The biopsy specimens were analyzed histomorphometrically to measure the dimensional changes among 3 tissue types: epithelial layer, connective tissue area, and new bone tissue area. Fifty-five specimens from sites of previously advanced periodontal disease from 45 patients were included in the disease group. Another 12 specimens of previously healthy extraction sockets were collected from 12 different patients as a control. The postextraction period of the disease group varied from 2 to 42 weeks. In the disease group, connective tissue occupied most of the socket during the first 4 weeks. New bone area progressively replaced the connective tissue area after the first 4 weeks. The area proportion of new bone tissue exceeded that of connective tissue by 14 weeks. After 20 weeks, most extraction sockets in the disease group demonstrated continuous new bone formation. The control group exhibited almost complete socket healing after 10 weeks, with no more new bone formation after 20 weeks. Osseous regeneration in the diseased sockets developed more slowly than in the disease-free sockets. After 16 weeks, new bone area exceeded 50% of the total newly regenerated tissue in the sockets with severe periodontal destruction. In the control group, after 8 weeks, new bone area exceeded 50% of the total tissue.

Collagen-Based Biomaterials for Wound Healing

PubMed Central

Chattopadhyay, Sayani; Raines, Ronald T.

2014-01-01

With its wide distribution in soft and hard connective tissues, collagen is the most abundant of animal proteins. In vitro, natural collagen can be formed into highly organized, three-dimensional scaffolds that are intrinsically biocompatible, biodegradable, non-toxic upon exogenous application, and endowed with high tensile strength. These attributes make collagen the material of choice for wound healing and tissue engineering applications. In this article, we review the structure and molecular interactions of collagen in vivo; the recent use of natural collagen in sponges, injectables, films and membranes, dressings, and skin grafts; and the on-going development of synthetic collagen mimetic peptides as pylons to anchor cytoactive agents in wound beds. PMID:24633807

Proton beams in radiotherapy

NASA Astrophysics Data System (ADS)

Khoroshkov, V. S.; Minakova, E. I.

1998-11-01

A branch of radiology, proton therapy employs fast protons as a tool for the treatment of various, mainly oncological, diseases. The features of tissue ionization by protons (Bragg peak) facilitate a further step towards solving the principal challenge in radiology: to deliver a sufficiently high and homogeneous dose to virtually any tumour, while sparing healthy neighbouring tissues, organs and structures. The state of the art of proton therapy is described, as well as the main technical, physics and clinical results gained since the 1950s at high-energy physics centres worldwide. The future of proton therapy is connected with the construction of hospital-based facilities with dedicated medical accelerators and modern technical instrumentation.

Towards a comprehensive understanding of emerging dynamics and function of pancreatic islets: A complex network approach. Comment on "Network science of biological systems at different scales: A review" by Gosak et al.

NASA Astrophysics Data System (ADS)

Loppini, Alessandro

2018-03-01

Complex network theory represents a comprehensive mathematical framework to investigate biological systems, ranging from sub-cellular and cellular scales up to large-scale networks describing species interactions and ecological systems. In their exhaustive and comprehensive work [1], Gosak et al. discuss several scenarios in which the network approach was able to uncover general properties and underlying mechanisms of cells organization and regulation, tissue functions and cell/tissue failure in pathology, by the study of chemical reaction networks, structural networks and functional connectivities.

Spontaneous coronary artery dissection and its association with heritable connective tissue disorders.

PubMed

Henkin, Stanislav; Negrotto, Sara M; Tweet, Marysia S; Kirmani, Salman; Deyle, David R; Gulati, Rajiv; Olson, Timothy M; Hayes, Sharonne N

2016-06-01

Spontaneous coronary artery dissection (SCAD) is an under-recognised but important cause of myocardial infarction and sudden cardiac death. We sought to determine the role of medical and molecular genetic screening for connective tissue disorders in patients with SCAD. We performed a single-centre retrospective descriptive analysis of patients with spontaneous coronary artery disease who had undergone medical genetics evaluation 1984-2014 (n=116). The presence or absence of traits suggestive of heritable connective tissue disease was extracted. Genetic testing for connective tissue disorders and/or aortopathies, if performed, is also reported. Of the 116 patients (mean age 44.2 years, 94.8% women and 41.4% with non-coronary fibromuscular dysplasia (FMD)), 59 patients underwent genetic testing, of whom 3 (5.1%) received a diagnosis of connective tissue disorder: a 50-year-old man with Marfan syndrome; a 43-year-old woman with vascular Ehlers-Danlos syndrome and FMD; and a 45-year-old woman with vascular Ehlers-Danlos syndrome. An additional 12 patients (20.3%) had variants of unknown significance, none of which was thought to be a definite disease-causing mutation based on in silico analyses. Only a minority of patients with SCAD who undergo genetic evaluation have a likely pathogenic mutation identified on gene panel testing. Even fewer exhibit clinical features of connective tissue disorder. These findings underscore the need for further studies to elucidate the molecular mechanisms of SCAD. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Portable bioreactor for perfusion and electrical stimulation of engineered cardiac tissue.

PubMed

Tandon, Nina; Taubman, Alanna; Cimetta, Elisa; Saccenti, Laetitia; Vunjak-Novakovic, Gordana

2013-01-01

Cardiac tissue engineering aims to create functional tissue constructs that can reestablish the structure and function of injured myocardium. Although bioreactors have facilitated the engineering of cardiac patches of clinically relevant size in vitro, a major drawback remains the transportation of the engineered tissues from a production facility to a medical operation facility while maintaining tissue viability and preventing contamination. Furthermore, after implantation, most of the cells are endangered by hypoxic conditions that exist before vascular flow is established. We developed a portable device that provides the perfusion and electrical stimulation necessary to engineer cardiac tissue in vitro, and to transport it to the site where it will be implantated. The micropump-powered perfusion apparatus may additionally function as an extracorporeal active pumping system providing nutrients and oxygen supply to the graft post-implantation. Such a system, through perfusion of oxygenated media and bioactive molecules (e.g. growth factors), could transiently support the tissue construct until it connects to the host vasculature and heart muscle, after which it could be taken away or let biodegrade.

Effect of Tissucol on connective tissue matrix during wound healing: an immunohistochemical study in rat skin.

PubMed

Romanos, G E; Strub, J R

1998-03-05

Fibrin sealants are very useful in different surgical fields. Fixation of free gingival grafts, root coverage procedures, and other techniques increasing connective tissue attachment may be associated with the application of Tissucol in periodontology. The aim of this study was to evaluate the influence of the fibrin sealant in the extracellular matrix, as well as alterations of the connective tissue matrix during wound-healing processes. In the back dermis of 15 Net male rats, Tissucol was implanted after intraperitoneal anesthesia. The implant material was placed in subcutaneous pockets (2 cm in length) which were sutured with interproximal sutures (test and control pockets). At 4, 7, 14, 21, and 28 days after surgery, biopsies of the healed and surrounding tissues were taken, frozen in liquid nitrogen, and examined histologically and immunohistochemically with antibodies against collagen types I, III, IV, V, VI, and VII. The findings showed thick and thin collagen type I and III fibers, respectively, with different orientations localized around the implant material. An increased amount of blood vessels and capillaries (their basement membranes containing collagen type IV) was observed during wound healing which may be associated with the implantation of the sealant. Collagen type V fibers were localized from the first days to the 4th postoperative week and, without any inflammatory reaction (according to histologic staining), formed a fibrillar extracellular matrix with high collagenase resistance. Collagen type VI showed a microfibrillar pattern of distribution, and collagen type VII was localized in the dermo epidermo junction and very deep in the connective tissue in the form of anchoring fibers (only in the test group) during the 4 postoperative weeks of healing. The data showed that Tissucol is a biocompatible component which cannot produce any extensive inflammatory reaction in the matrix. New blood vessel formation, an epithelial-connective tissue interface with high stability, as well as matrix alterations with high resistance in the proteolytic enzymes (i.e., collagenases) can be induced in the connective tissue after use of a fibrin sealant. All of these characteristics may be of great importance in connective tissue healing in periodontal surgical procedures.

Interaction of Vascular Smooth Muscle Cells Under Low Shear Stress

NASA Technical Reports Server (NTRS)

Seidel, Charles L.

1998-01-01

The blood vessel wall consists of three cellular layers, an outer adventitial, a middle medial and an inner intimal layer. When the blood vessel forms in the embryo it begins as a tube composed of a single cell type called endothelial cells. Over time, other cells are recruited from the surrounding tissue to form additional layers on the outer surface of the endothelial tube. The cells that are recruited are called mesenchymal cells. Mesenchymal cells are responsible for the production of connective tissue that holds the blood vessel together and for developing into vascular smooth muscle cells that are responsible for regulating the diameter of the vessel (1) and therefore, blood flow. In a fully developed blood vessel, the endothelial cells make- up the majority of cells in the intimal layer while the mesenchymal cells make-up the majority of cells in the medial and adventitial layers. Within the medial layer of a mature vessel, cells are organized into multiple circular layers of alternating bands of connective tissue and cells. The cell layer is composed of a mixture of mesenchymal cells that have not developed into smooth muscle cells and fully developed smooth muscle cells (2). The assembly and organization of complex tissues is directed in part by a signaling system composed of proteins on the cell surface called adhesion molecules. Adhesion molecules enable cells to recognize each other as well as the composition of the connective tissue in which they reside (3). It was hypothesized that the different cell types that compose the vascular wall possess different adhesion molecules that enable them to recognize each other and through this recognition system, form the complex layered organization of the vascular wall. In other words, the layered organization is an intrinsic property of the cells. If this hypothesis is correct then the different cells that make up the vessel wall, when mixed together, should organize themselves into a layered structure resembling an intact blood vessel. Experiments described below were designed to test this hypothesis.

Microgravity Stress: Bone and Connective Tissue.

PubMed

Bloomfield, Susan A; Martinez, Daniel A; Boudreaux, Ramon D; Mantri, Anita V

2016-03-15

The major alterations in bone and the dense connective tissues in humans and animals exposed to microgravity illustrate the dependency of these tissues' function on normal gravitational loading. Whether these alterations depend solely on the reduced mechanical loading of zero g or are compounded by fluid shifts, altered tissue blood flow, radiation exposure, and altered nutritional status is not yet well defined. Changes in the dense connective tissues and intervertebral disks are generally smaller in magnitude but occur more rapidly than those in mineralized bone with transitions to 0 g and during recovery once back to the loading provided by 1 g conditions. However, joint injuries are projected to occur much more often than the more catastrophic bone fracture during exploration class missions, so protecting the integrity of both tissues is important. This review focuses on the research performed over the last 20 years in humans and animals exposed to actual spaceflight, as well as on knowledge gained from pertinent ground-based models such as bed rest in humans and hindlimb unloading in rodents. Significant progress has been made in our understanding of the mechanisms for alterations in bone and connective tissues with exposure to microgravity, but intriguing questions remain to be solved, particularly with reference to biomedical risks associated with prolonged exploration missions. Copyright © 2016 John Wiley & Sons, Inc.

Nevus lipomatosus cutaneous superficialis with perifollicular fibrosis.

PubMed

Takashima, Hideki; Toyoda, Masahiko; Ikeda, Yoko; Kagoura, Masayori; Morohashi, Masaaki

2003-01-01

Nevus lipomatosus cutaneous superficialis (NLCS) is a rare hamartomatous skin lesion histopathologically characterized by the presence of mature fat tissue even within the upper dermis. Clinically, two types of NLCS can be distinguished; a multiple type and a solitary type. We here report a 10-month-old girl showing multiple type NLCS as a collection of a nodule and papules on her right abdomen. Histological examination revealed that the lesion was composed of a lobular proliferation of fat tissue throughout the dermis and immature hair follicle-like structures with perifollicular fibrosis. Histological alterations of the dermal connective tissue components were also seen, including thickening of collagen bundles and increased numbers of both fibroblasts and blood vessels. This is the first reported case of NLCS with perifollicular fibrosis. Copyright John Libbey Eurotext 2003

Tissue Integration of a Volume-Stable Collagen Matrix in an Experimental Soft Tissue Augmentation Model.

PubMed

Ferrantino, Luca; Bosshardt, Dieter; Nevins, Myron; Santoro, Giacomo; Simion, Massimo; Kim, David

Reducing the need for a connective tissue graft by using an efficacious biomaterial is an important task for dental professionals and patients. This experimental study aimed to test the soft tissue response to a volume-stable new collagen matrix. The device demonstrated good stability during six different time points ranging from 0 to 90 days of healing with no alteration of the wound-healing processes. The 90-day histologic specimen demonstrates eventual replacement of most of the matrix with new connective tissue fibers.

Polydopamine deposition with anodic oxidation for better connective tissue attachment to transmucosal implants.

PubMed

Teng, F; Chen, H; Xu, Y; Liu, Y; Ou, G

2018-04-01

Nowadays, most designs for the transmucosal surface of implants are machined-smooth. However, connective tissue adhered to the smooth surface of an implant has poor mechanical resistance, which can render separation of tissue from the implant interface and induce epithelial downgrowth. Modification of the transmucosal surface of implants, which can help form a good seal of connective tissue, is therefore desired. We hypothesized that anodic oxidation (AO) and polydopamine (PD) deposition could be used to enhance the attachment between an implant and peri-implant connective tissue. We tested this hypothesis in the mandibles of Beagle dogs. AO and PD were used to modify the transmucosal region of transmucosal implants (implant neck). The surface microstructure, surface roughness and elemental composition were investigated in vitro. L929 mouse fibroblasts were cultured to test the effect of PD on cell adhesion. Six Beagle dogs were used for the in vivo experiment (n = 6 dogs per group). Three months after building the edentulous animal model, four groups of implants (control, AO, PD and AO + PD) were inserted. After 4 months of healing, samples were harvested for histometric analyses. The surfaces of anodized implant necks were overlaid with densely distributed pores, 2-7 μm in size. On the PD-modified surfaces, N1s, the chemical bond of nitrogen in PD, was detected using X-ray photoelectron spectroscopy. L929 developed pseudopods more quickly on the PD-modified surfaces than on the surfaces of the control group. The in vivo experiment showed a longer connective tissue seal and a more coronally located peri-implant soft-tissue attachment in the AO + PD group than in the control group (P < .05). The modification of AO + PD on the implant neck yielded better attachment between the implant and peri-implant connective tissue. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Exostosis following a subepithelial connective tissue graft.

PubMed

Corsair, A J; Iacono, V J; Moss, S S

2001-04-01

This case report describes the formation of an unusual unaesthetic gingival enlargement during a five year post operative period subsequent to a subepithelial connective tissue graft placed facial to teeth #4 and #6. Histological assessment of the enlarged tissue indicated that it consisted of viable bone and marrow. The exostosis was reduced with rotary instruments and acceptable soft tissue aesthetics were created using a carbon dioxide laser for gingivoplasty. Possible causes for this unusual enlargement are discussed.

A survey of clearing techniques for 3D imaging of tissues with special reference to connective tissue.

PubMed

Azaripour, Adriano; Lagerweij, Tonny; Scharfbillig, Christina; Jadczak, Anna Elisabeth; Willershausen, Brita; Van Noorden, Cornelis J F

2016-08-01

For 3-dimensional (3D) imaging of a tissue, 3 methodological steps are essential and their successful application depends on specific characteristics of the type of tissue. The steps are 1° clearing of the opaque tissue to render it transparent for microscopy, 2° fluorescence labeling of the tissues and 3° 3D imaging. In the past decades, new methodologies were introduced for the clearing steps with their specific advantages and disadvantages. Most clearing techniques have been applied to the central nervous system and other organs that contain relatively low amounts of connective tissue including extracellular matrix. However, tissues that contain large amounts of extracellular matrix such as dermis in skin or gingiva are difficult to clear. The present survey lists methodologies that are available for clearing of tissues for 3D imaging. We report here that the BABB method using a mixture of benzyl alcohol and benzyl benzoate and iDISCO using dibenzylether (DBE) are the most successful methods for clearing connective tissue-rich gingiva and dermis of skin for 3D histochemistry and imaging of fluorescence using light-sheet microscopy. Copyright © 2016 The Authors. Published by Elsevier GmbH.. All rights reserved.

Three-dimensional mapping of microcircuit correlation structure

PubMed Central

Cotton, R. James; Froudarakis, Emmanouil; Storer, Patrick; Saggau, Peter; Tolias, Andreas S.

2013-01-01

Great progress has been made toward understanding the properties of single neurons, yet the principles underlying interactions between neurons remain poorly understood. Given that connectivity in the neocortex is locally dense through both horizontal and vertical connections, it is of particular importance to characterize the activity structure of local populations of neurons arranged in three dimensions. However, techniques for simultaneously measuring microcircuit activity are lacking. We developed an in vivo 3D high-speed, random-access two-photon microscope that is capable of simultaneous 3D motion tracking. This allows imaging from hundreds of neurons at several hundred Hz, while monitoring tissue movement. Given that motion will induce common artifacts across the population, accurate motion tracking is absolutely necessary for studying population activity with random-access based imaging methods. We demonstrate the potential of this imaging technique by measuring the correlation structure of large populations of nearby neurons in the mouse visual cortex, and find that the microcircuit correlation structure is stimulus-dependent. Three-dimensional random access multiphoton imaging with concurrent motion tracking provides a novel, powerful method to characterize the microcircuit activity in vivo. PMID:24133414

Normal anatomy and biomechanics of the knee.

PubMed

Flandry, Fred; Hommel, Gabriel

2011-06-01

Functionally, the knee comprises 2 articulations-the patellofemoral and tibiofemoral. Stability of the joint is governed by a combination of static ligaments, dynamic muscular forces, meniscocapsular aponeurosis, bony topography, and joint load. The surgeon is ill equipped to undertake surgical treatment of a dislocated knee without a sound footing in the anatomic complexities of this joint. We review the normal anatomy of the knee, emphasizing connective tissue structures and common injury patterns.

The tensile strength characteristics study of the laser welds of biological tissue using the nanocomposite solder

NASA Astrophysics Data System (ADS)

Rimshan, I. B.; Ryabkin, D. I.; Savelyev, M. S.; Zhurbina, N. N.; Pyanov, I. V.; Eganova, E. M.; Pavlov, A. A.; Podgaetsky, V. M.; Ichkitidze, L. P.; Selishchev, S. V.; Gerasimenko, A. Y.

2016-04-01

Laser welding device for biological tissue has been developed. The main device parts are the radiation system and adaptive thermal stabilization system of welding area. Adaptive thermal stabilization system provided the relation between the laser radiation intensity and the weld temperature. Using atomic force microscopy the structure of composite which is formed by the radiation of laser solder based on aqua- albuminous dispersion of multi-walled carbon nanotubes was investigated. AFM topograms nanocomposite solder are mainly defined by the presence of pores in the samples. In generally, the surface structure of composite is influenced by the time, laser radiation power and MWCNT concentration. Average size of backbone nanoelements not exceeded 500 nm. Bulk density of nanoelements was in the range 106-108 sm-3. The data of welding temperature maintained during the laser welding process and the corresponding tensile strength values were obtained. Maximum tensile strength of the suture was reached in the range 50-55°C. This temperature and the pointwise laser welding technology (point area ~ 2.5mm) allows avoiding thermal necrosis of healthy section of biological tissue and provided reliable bonding construction of weld join. In despite of the fact that tensile strength values of the samples are in the range of 15% in comparison with unbroken strips of pigskin leather. This situation corresponds to the initial stage of the dissected tissue connection with a view to further increasing of the joint strength of tissues with the recovery of tissue structure; thereby achieved ratio is enough for a medical practice in certain cases.

The role of capillaroscopy and thermography in the assessment and management of Raynaud's phenomenon.

PubMed

Herrick, Ariane L; Murray, Andrea

2018-05-01

Most patients with Raynaud's phenomenon (RP) have "benign" primary RP (PRP), but a minority have an underlying cause, for example a connective tissue disease such as systemic sclerosis (SSc). Secondary RP can be associated with structural as well as functional digital vascular changes and can be very severe, potentially progressing to digital ulceration or gangrene. The first step in management is to establish why the patient has RP. This short review discusses the role of nailfold capillaroscopy and thermography in the assessment of RP. Nailfold capillaroscopy examines microvascular structure, which is normal in PRP but abnormal in most patients with SSc: the inclusion of abnormal nailfold capillaries into the 2013 classification criteria for SSc behoves clinicians diagnosing connective tissue disease to be familiar with the technique. For those without access to the gold standard of high magnification videocapillaroscopy, a low magnification dermatoscope or USB microscope can be used. Thermography measures surface temperature and is therefore an indirect measure of blood blow, assessing digital vascular function (abnormal in both PRP and SSc). Until now, the use of thermography has been mainly confined to specialist centres and used mainly in research: this may change with development of mobile phone thermography. Copyright © 2018 Elsevier B.V. All rights reserved.

The role of fasciae in Civinini–Morton's syndrome

PubMed Central

Stecco, Carla; Fantoni, Ilaria; Macchi, Veronica; Del Borrello, Mario; Porzionato, Andrea; Biz, Carlo; De Caro, Raffaele

2015-01-01

This study evaluates the pathogenetic role of the perineural connective tissue and foot fasciae in Civinini–Morton's neuroma. Eleven feet (seven male, four female; mean age: 70.9 years) were dissected to analyse the anatomy of inter-metatarsal space, particularly the dorsal and plantar fasciae and metatarsal transverse ligament (DMTL). The macrosections were prepared for microscopic analysis. Ten Civinini–Morton neuromas obtained from surgery were also analysed. Magnetic resonance images (MRIs) from 40 patients and 29 controls were compared. Dissections showed that the width of the inter-metatarsal space is established by two fibrous structures: the dorsal foot fascia and the DMTL, which, together, connect the metatarsal bones and resist their splaying. Interosseous muscles spread out into the dorsal fascia of the foot, defining its basal tension. The common digital plantar nerve (CDPN) is encased in concentric layers of fibrous and loose connective tissue, continuous with the vascular sheath and deep foot fascia. Outside this sheath, fibroelastic septa, from DMTL to plantar fascia, and little fat lobules are present, further protecting the nerve against compressive stress. The MRI study revealed high inter-individual variability in the forefoot structures, although only the thickness of the dorsal fascia represented a statistically significant difference between cases and controls. It was hypothesized that alterations in foot support and altered biomechanics act on the interosseous muscles, increasing the stiffness of the dorsal fascia, particularly at the points where these muscles are inserted. Chronic rigidity of this fascia increases the stiffness of the inter-metatarsal space, leading to entrapment of the CDPN. PMID:26467241

WE-DE-202-00: Connecting Radiation Physics with Computational Biology

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

Radiation therapy for the treatment of cancer has been established as a highly precise and effective way to eradicate a localized region of diseased tissue. To achieve further significant gains in the therapeutic ratio, we need to move towards biologically optimized treatment planning. To achieve this goal, we need to understand how the radiation-type dependent patterns of induced energy depositions within the cell (physics) connect via molecular, cellular and tissue reactions to treatment outcome such as tumor control and undesirable effects on normal tissue. Several computational biology approaches have been developed connecting physics to biology. Monte Carlo simulations are themore » most accurate method to calculate physical dose distributions at the nanometer scale, however simulations at the DNA scale are slow and repair processes are generally not simulated. Alternative models that rely on the random formation of individual DNA lesions within one or two turns of the DNA have been shown to reproduce the clusters of DNA lesions, including single strand breaks (SSBs), double strand breaks (DSBs) without the need for detailed track structure simulations. Efficient computational simulations of initial DNA damage induction facilitate computational modeling of DNA repair and other molecular and cellular processes. Mechanistic, multiscale models provide a useful conceptual framework to test biological hypotheses and help connect fundamental information about track structure and dosimetry at the sub-cellular level to dose-response effects on larger scales. In this symposium we will learn about the current state of the art of computational approaches estimating radiation damage at the cellular and sub-cellular scale. How can understanding the physics interactions at the DNA level be used to predict biological outcome? We will discuss if and how such calculations are relevant to advance our understanding of radiation damage and its repair, or, if the underlying biological processes are too complex for a mechanistic approach. Can computer simulations be used to guide future biological research? We will debate the feasibility of explaining biology from a physicists’ perspective. Learning Objectives: Understand the potential applications and limitations of computational methods for dose-response modeling at the molecular, cellular and tissue levels Learn about mechanism of action underlying the induction, repair and biological processing of damage to DNA and other constituents Understand how effects and processes at one biological scale impact on biological processes and outcomes on other scales J. Schuemann, NCI/NIH grantsS. McMahon, Funding: European Commission FP7 (grant EC FP7 MC-IOF-623630)« less

Random forest classification of large volume structures for visuo-haptic rendering in CT images

NASA Astrophysics Data System (ADS)

Mastmeyer, Andre; Fortmeier, Dirk; Handels, Heinz

2016-03-01

For patient-specific voxel-based visuo-haptic rendering of CT scans of the liver area, the fully automatic segmentation of large volume structures such as skin, soft tissue, lungs and intestine (risk structures) is important. Using a machine learning based approach, several existing segmentations from 10 segmented gold-standard patients are learned by random decision forests individually and collectively. The core of this paper is feature selection and the application of the learned classifiers to a new patient data set. In a leave-some-out cross-validation, the obtained full volume segmentations are compared to the gold-standard segmentations of the untrained patients. The proposed classifiers use a multi-dimensional feature space to estimate the hidden truth, instead of relying on clinical standard threshold and connectivity based methods. The result of our efficient whole-body section classification are multi-label maps with the considered tissues. For visuo-haptic simulation, other small volume structures would have to be segmented additionally. We also take a look into these structures (liver vessels). For an experimental leave-some-out study consisting of 10 patients, the proposed method performs much more efficiently compared to state of the art methods. In two variants of leave-some-out experiments we obtain best mean DICE ratios of 0.79, 0.97, 0.63 and 0.83 for skin, soft tissue, hard bone and risk structures. Liver structures are segmented with DICE 0.93 for the liver, 0.43 for blood vessels and 0.39 for bile vessels.

Spatiotemporally Controlled Microchannels of Periodontal Mimic Scaffolds

PubMed Central

Park, C.H.; Kim, K.H.; Rios, H.F.; Lee, Y.M.; Giannobile, W.V.; Seol, Y.J.

2014-01-01

Physiologic bioengineering of the oral, dental, and craniofacial complex requires optimized geometric organizations of fibrous connective tissues. A computer-designed, fiber-guiding scaffold has been developed to promote tooth-supporting periodontal tissue regeneration and functional restoration despite limited printing resolution for the manufacture of submicron-scaled features. Here, we demonstrate the use of directional freeze-casting techniques to control pore directional angulations and create mimicked topographies to alveolar crest, horizontal, oblique, and apical fibers of natural periodontal ligaments. For the differing anatomic positions, the gelatin displayed varying patterns of ice growth, determined via internal pore architectures. Regardless of the freezing coordinates, the longitudinal pore arrangements resulted in submicron-scaled diameters (~50 µm), along with corresponding high biomaterial porosity (~90%). Furthermore, the horizontal + coronal ((x→−y→) freezing orientation facilitated the creation of similar structures to major fibers in the periodontal ligament interface. This periodontal tissue-mimicking microenvironment is a potential tissue platform for the generation of naturally oriented ligamentous tissues consistent with periodontal ligament neogenesis. PMID:25216511

Connective tissue ulcers.

PubMed

Dabiri, Ganary; Falanga, Vincent

2013-11-01

Connective tissue disorders (CTD), which are often also termed collagen vascular diseases, include a number of related inflammatory conditions. Some of these diseases include rheumatoid arthritis, systemic lupus erythematosus, systemic sclerosis (scleroderma), localized scleroderma (morphea variants localized to the skin), Sjogren's syndrome, dermatomyositis, polymyositis, and mixed connective tissue disease. In addition to the systemic manifestations of these diseases, there are a number of cutaneous features that make these conditions recognizable on physical exam. Lower extremity ulcers and digital ulcers are an infrequent but disabling complication of long-standing connective tissue disease. The exact frequency with which these ulcers occur is not known, and the cause of the ulcerations is often multifactorial. Moreover, a challenging component of CTD ulcerations is that there are still no established guidelines for their diagnosis and treatment. The morbidity associated with these ulcerations and their underlying conditions is very substantial. Indeed, these less common but intractable ulcers represent a major medical and economic problem for patients, physicians and nurses, and even well organized multidisciplinary wound healing centers. Copyright © 2013 Tissue Viability Society. Published by Elsevier Ltd. All rights reserved.

Outcomes of sympathectomy and vascular bypass for digital ischaemia in connective tissue disorders.

PubMed

Shammas, R L; Hwang, B H; Levin, L S; Richard, M J; Ruch, D S; Mithani, S K

2017-10-01

All patients (36 hands) with connective tissue disorders who underwent periarterial sympathectomy of the hand alone or in conjunction with vascular bypass at our institution between 1995-2013 were reviewed. The durable resolution of ulcers was significantly higher in patients treated by periarterial sympathectomy and bypass than in patients treated by periarterial sympathectomy alone. Although there were more digital amputations in patients treated by periarterial sympathectomy alone, the difference was not statistically significant. Vascular bypass in conjunction with sympathectomy may be better than sympathectomy alone in patients with digital ischaemia related to connective tissue disorders. IV.

Personal Authentication Analysis Using Finger-Vein Patterns in Patients with Connective Tissue Diseases—Possible Association with Vascular Disease and Seasonal Change -

PubMed Central

Kono, Miyuki; Miura, Naoto; Fujii, Takao; Ohmura, Koichiro; Yoshifuji, Hajime; Yukawa, Naoichiro; Imura, Yoshitaka; Nakashima, Ran; Ikeda, Takaharu; Umemura, Shin-ichiro; Miyatake, Takafumi; Mimori, Tsuneyo

2015-01-01

Objective To examine how connective tissue diseases affect finger-vein pattern authentication. Methods The finger-vein patterns of 68 patients with connective tissue diseases and 24 healthy volunteers were acquired. Captured as CCD (charge-coupled device) images by transmitting near-infrared light through fingers, they were followed up in once in each season for one year. The similarity of the follow-up patterns and the initial one was evaluated in terms of their normalized cross-correlation C. Results The mean C values calculated for patients tended to be lower than those calculated for healthy volunteers. In midwinter (February in Japan) they showed statistically significant reduction both as compared with patients in other seasons and as compared with season-matched healthy controls, whereas the values calculated for healthy controls showed no significant seasonal changes. Values calculated for patients with systemic sclerosis (SSc) or mixed connective tissue disease (MCTD) showed major reductions in November and, especially, February. Patients with rheumatoid arthritis (RA) and patients with dermatomyositis or polymyositis (DM/PM) did not show statistically significant seasonal changes in C values. Conclusions Finger-vein patterns can be used throughout the year to identify patients with connective tissue diseases, but some attention is needed for patients with advanced disease such as SSc. PMID:26701644

Recessive and dominant mutations in COL12A1 cause a novel EDS/myopathy overlap syndrome in humans and mice

PubMed Central

Zou, Yaqun; Zwolanek, Daniela; Izu, Yayoi; Gandhy, Shreya; Schreiber, Gudrun; Brockmann, Knut; Devoto, Marcella; Tian, Zuozhen; Hu, Ying; Veit, Guido; Meier, Markus; Stetefeld, Jörg; Hicks, Debbie; Straub, Volker; Voermans, Nicol C.; Birk, David E.; Barton, Elisabeth R.; Koch, Manuel; Bönnemann, Carsten G.

2014-01-01

Collagen VI-related myopathies are disorders of connective tissue presenting with an overlap phenotype combining clinical involvement from the muscle and from the connective tissue. Not all patients displaying related overlap phenotypes between muscle and connective tissue have mutations in collagen VI. Here, we report a homozygous recessive loss of function mutation and a de novo dominant mutation in collagen XII (COL12A1) as underlying a novel overlap syndrome involving muscle and connective tissue. Two siblings homozygous for a loss of function mutation showed widespread joint hyperlaxity combined with weakness precluding independent ambulation, while the patient with the de novo missense mutation was more mildly affected, showing improvement including the acquisition of walking. A mouse model with inactivation of the Col12a1 gene showed decreased grip strength, a delay in fiber-type transition and a deficiency in passive force generation while the muscle seems more resistant to eccentric contraction induced force drop, indicating a role for a matrix-based passive force-transducing elastic element in the generation of the weakness. This new muscle connective tissue overlap syndrome expands on the emerging importance of the muscle extracellular matrix in the pathogenesis of muscle disease. PMID:24334604

Esophageal involvement and interstitial lung disease in mixed connective tissue disease.

PubMed

Fagundes, M N; Caleiro, M T C; Navarro-Rodriguez, T; Baldi, B G; Kavakama, J; Salge, J M; Kairalla, R; Carvalho, C R R

2009-06-01

Mixed connective tissue disease is a systemic inflammatory disorder that results in both pulmonary and esophageal manifestations. We sought to evaluate the relationship between esophageal dysfunction and interstitial lung disease in patients with mixed connective tissue disease. We correlated the pulmonary function data and the high-resolution computed tomography findings of interstitial lung disease with the results of esophageal evaluation in manometry, 24-hour intraesophageal pH measurements, and the presence of esophageal dilatation on computed tomography scan. Fifty consecutive patients with mixed connective tissue disease, according to Kasukawa's classification criteria, were included in this prospective study. High-resolution computed tomography parenchymal abnormalities were present in 39 of 50 patients. Esophageal dilatation, gastroesophageal reflux, and esophageal motor impairment were also very prevalent (28 of 50, 18 of 36, and 30 of 36, respectively). The presence of interstitial lung disease on computed tomography was significantly higher among patients with esophageal dilatation (92% vs. 45%; p<0.01) and among patients with severe motor dysfunction (90% vs. 35%; p<0.001). Although we were not able to prove a causal relationship between esophageal and pulmonary involvement, our series revealed a strong association between esophageal motor dysfunction and interstitial lung disease in patients with mixed connective tissue disease.

PDGFRα plays a crucial role in connective tissue remodeling.

PubMed

Horikawa, Shinjiro; Ishii, Yoko; Hamashima, Takeru; Yamamoto, Seiji; Mori, Hisashi; Fujimori, Toshihiko; Shen, Jie; Inoue, Ran; Nishizono, Hirofumi; Itoh, Hiroshi; Majima, Masataka; Abraham, David; Miyawaki, Toshio; Sasahara, Masakiyo

2015-12-07

Platelet derived growth factor (PDGF) plays a pivotal role in the remodeling of connective tissues. Emerging data indicate the distinctive role of PDGF receptor-α (PDGFRα) in this process. In the present study, the Pdgfra gene was systemically inactivated in adult mouse (α-KO mouse), and the role of PDGFRα was examined in the subcutaneously implanted sponge matrices. PDGFRα expressed in the fibroblasts of Pdgfra-preserving control mice (Flox mice), was significantly reduced in the sponges in α-KO mice. Neovascularized areas were largely suppressed in the α-KO mice than in the Flox mice, whereas the other parameters related to the blood vessels and endothelial cells were similar. The deposition of collagen and fibronectin and the expression of collagen 1a1 and 3a1 genes were significantly reduced in α-KO mice. There was a significantly decrease in the number and dividing fibroblasts in the α-KO mice, and those of macrophages were similar between the two genotypes. Hepatocyte growth factor (Hgf) gene expression was suppressed in Pdgfra-inactivated fibroblasts and connective tissue. The findings implicate the role of PDGFRα-dependent ECM and HGF production in fibroblasts that promotes the remodeling of connective tissue and suggest that PDGFRα may be a relevant target to regulate connective tissue remodeling.

PDGFRα plays a crucial role in connective tissue remodeling

PubMed Central

Horikawa, Shinjiro; Ishii, Yoko; Hamashima, Takeru; Yamamoto, Seiji; Mori, Hisashi; Fujimori, Toshihiko; Shen, Jie; Inoue, Ran; Nishizono, Hirofumi; Itoh, Hiroshi; Majima, Masataka; Abraham, David; Miyawaki, Toshio; Sasahara, Masakiyo

2015-01-01

Platelet derived growth factor (PDGF) plays a pivotal role in the remodeling of connective tissues. Emerging data indicate the distinctive role of PDGF receptor-α (PDGFRα) in this process. In the present study, the Pdgfra gene was systemically inactivated in adult mouse (α-KO mouse), and the role of PDGFRα was examined in the subcutaneously implanted sponge matrices. PDGFRα expressed in the fibroblasts of Pdgfra-preserving control mice (Flox mice), was significantly reduced in the sponges in α-KO mice. Neovascularized areas were largely suppressed in the α-KO mice than in the Flox mice, whereas the other parameters related to the blood vessels and endothelial cells were similar. The deposition of collagen and fibronectin and the expression of collagen 1a1 and 3a1 genes were significantly reduced in α-KO mice. There was a significantly decrease in the number and dividing fibroblasts in the α-KO mice, and those of macrophages were similar between the two genotypes. Hepatocyte growth factor (Hgf) gene expression was suppressed in Pdgfra-inactivated fibroblasts and connective tissue. The findings implicate the role of PDGFRα-dependent ECM and HGF production in fibroblasts that promotes the remodeling of connective tissue and suggest that PDGFRα may be a relevant target to regulate connective tissue remodeling. PMID:26639755

Epitope mapping of the U1 small nuclear ribonucleoprotein particle in patients with systemic lupus erythematosus and mixed connective tissue disease.

PubMed

Somarelli, J A; Mesa, A; Rodriguez, R; Avellan, R; Martinez, L; Zang, Y J; Greidinger, E L; Herrera, R J

2011-03-01

Systemic lupus erythematosus (SLE) and mixed connective tissue disease (MCTD) are autoimmune illnesses characterized by the presence of high titers of autoantibodies directed against a wide range of 'self ' antigens. Proteins of the U1 small nuclear ribonucleoprotein particle (U1 snRNP) are among the most immunogenic molecules in patients with SLE and MCTD. The recent release of a crystallized U1 snRNP provides a unique opportunity to evaluate the effects of tertiary and quaternary structures on autoantigenicity within the U1 snRNP. In the present study, an epitope map was created using the U1 snRNP crystal structure. A total of 15 peptides were tested in a cohort of 68 patients with SLE, 29 with MCTD and 26 healthy individuals and mapped onto the U1 snRNP structure. Antigenic sites were detected in a variety of structures and appear to include RNA binding domains, but mostly exclude regions necessary for protein-protein interactions. These data suggest that while some autoantibodies may target U1 snRNP proteins as monomers or apoptosis-induced, protease-digested fragments, others may recognize epitopes on assembled protein subcomplexes of the U1 snRNP. Although nearly all of the peptides are strong predictors of autoimmune illness, none were successful at distinguishing between SLE and MCTD. The antigenicity of some peptides significantly correlated with several clinical symptoms. This investigation implicitly highlights the complexities of autoimmune epitopes, and autoimmune illnesses in general, and demonstrates the variability of antigens in patient populations, all of which contribute to difficult clinical diagnoses.

Morphology of the Nasal Apparatus in Pygmy (Kogia Breviceps) and Dwarf (K. Sima) Sperm Whales.

PubMed

Thornton, Steven W; Mclellan, William A; Rommel, Sentiel A; Dillaman, Richard M; Nowacek, Douglas P; Koopman, Heather N; Pabst, D Ann

2015-07-01

Odontocete echolocation clicks are generated by pneumatically driven phonic lips within the nasal passage, and propagated through specialized structures within the forehead. This study investigated the highly derived echolocation structures of the pygmy (Kogia breviceps) and dwarf (K. sima) sperm whales through careful dissections (N = 18 K. breviceps, 6 K. sima) and histological examinations (N = 5 K. breviceps). This study is the first to show that the entire kogiid sound production and transmission pathway is acted upon by complex facial muscles (likely derivations of the m. maxillonasolabialis). Muscles appear capable of tensing and separating the solitary pair of phonic lips, which would control echolocation click frequencies. The phonic lips are enveloped by the "vocal cap," a morphologically complex, connective tissue structure unique to kogiids. Extensive facial muscles appear to control the position of this structure and its spatial relationship to the phonic lips. The vocal cap's numerous air crypts suggest that it may reflect sounds. Muscles encircling the connective tissue case that surrounds the spermaceti organ may change its shape and/or internal pressure. These actions may influence the acoustic energy transmitted from the phonic lips, through this lipid body, to the melon. Facial and rostral muscles act upon the length of the melon, suggesting that the sound "beam" can be focused as it travels through the melon and into the environment. This study suggests that the kogiid echolocation system is highly tunable. Future acoustic studies are required to test these hypotheses and gain further insight into the kogiid echolocation system. © 2015 Wiley Periodicals, Inc.

* Hierarchically Structured Electrospun Scaffolds with Chemically Conjugated Growth Factor for Ligament Tissue Engineering.

PubMed

Pauly, Hannah M; Sathy, Binulal N; Olvera, Dinorath; McCarthy, Helen O; Kelly, Daniel J; Popat, Ketul C; Dunne, Nicholas J; Haut Donahue, Tammy Lynn

2017-08-01

The anterior cruciate ligament (ACL) of the knee is vital for proper joint function and is commonly ruptured during sports injuries or car accidents. Due to a lack of intrinsic healing capacity and drawbacks with allografts and autografts, there is a need for a tissue-engineered ACL replacement. Our group has previously used aligned sheets of electrospun polycaprolactone nanofibers to develop solid cylindrical bundles of longitudinally aligned nanofibers. We have shown that these nanofiber bundles support cell proliferation and elongation and the hierarchical structure and material properties are similar to the native human ACL. It is possible to combine multiple nanofiber bundles to create a scaffold that attempts to mimic the macroscale structure of the ACL. The goal of this work was to develop a hierarchical bioactive scaffold for ligament tissue engineering using connective tissue growth factor (CTGF)-conjugated nanofiber bundles and evaluate the behavior of mesenchymal stem cells (MSCs) on these scaffolds in vitro and in vivo. CTGF was immobilized onto the surface of individual nanofiber bundles or scaffolds consisting of multiple nanofiber bundles. The conjugation efficiency and the release of conjugated CTGF were assessed using X-ray photoelectron spectroscopy, assays, and immunofluorescence staining. Scaffolds were seeded with MSCs and maintained in vitro for 7 days (individual nanofiber bundles), in vitro for 21 days (scaled-up scaffolds of 20 nanofiber bundles), or in vivo for 6 weeks (small scaffolds of 4 nanofiber bundles), and ligament-specific tissue formation was assessed in comparison to non-CTGF-conjugated control scaffolds. Results showed that CTGF conjugation encouraged cell proliferation and ligament-specific tissue formation in vitro and in vivo. The results suggest that hierarchical electrospun nanofiber bundles conjugated with CTGF are a scalable and bioactive scaffold for ACL tissue engineering.

[From Brownian motion to mind imaging: diffusion MRI].

PubMed

Le Bihan, Denis

2006-11-01

The success of diffusion MRI, which was introduced in the mid 1980s is deeply rooted in the powerful concept that during their random, diffusion-driven movements water molecules probe tissue structure at a microscopic scale well beyond the usual image resolution. The observation of these movements thus provides valuable information on the structure and the geometric organization of tissues. The most successful application of diffusion MRI has been in brain ischemia, following the discovery that water diffusion drops at a very early stage of the ischemic event. Diffusion MRI provides some patients with the opportunity to receive suitable treatment at a very acute stage when brain tissue might still be salvageable. On the other hand, diffusion is modulated by the spatial orientation of large bundles of myelinated axons running in parallel through in brain white matter. This feature can be exploited to map out the orientation in space of the white matter tracks and to visualize the connections between different parts of the brain on an individual basis. Furthermore, recent data suggest that diffusion MRI may also be used to visualize rapid dynamic tissue changes, such as neuronal swelling, associated with cortical activation, offering a new and direct approach to brain functional imaging.

Severe periodontitis in Marfan's syndrome: a case report.

PubMed

Straub, Antje M; Grahame, Rodney; Scully, Crispian; Tonetti, Maurizio S

2002-07-01

Connective tissue disorders, such as some forms of Ehlers-Danlos syndrome, have been associated with severe periodontitis. This report describes a case of Marfan's syndrome, an inherited disorder of connective tissue caused by mutations in the fibrillin-1 gene, in which the patient presented with severe periodontitis. At examination, an average full-mouth clinical attachment level loss of 5.6+/-2.1 mm, furcation involvement, and severe alveolar bone loss were observed in a 41-year-old Caucasian male. Tooth hypermobility was also present. This case appears to be the first documentation of severe periodontitis in a patient with Marfan's syndrome. It supports the hypothesis that a variety of connective tissue disorders may confer increased susceptibility to periodontal tissue breakdown.

Murine Electrophysiological Models of Cardiac Arrhythmogenesis

PubMed Central

2016-01-01

Cardiac arrhythmias can follow disruption of the normal cellular electrophysiological processes underlying excitable activity and their tissue propagation as coherent wavefronts from the primary sinoatrial node pacemaker, through the atria, conducting structures and ventricular myocardium. These physiological events are driven by interacting, voltage-dependent, processes of activation, inactivation, and recovery in the ion channels present in cardiomyocyte membranes. Generation and conduction of these events are further modulated by intracellular Ca2+ homeostasis, and metabolic and structural change. This review describes experimental studies on murine models for known clinical arrhythmic conditions in which these mechanisms were modified by genetic, physiological, or pharmacological manipulation. These exemplars yielded molecular, physiological, and structural phenotypes often directly translatable to their corresponding clinical conditions, which could be investigated at the molecular, cellular, tissue, organ, and whole animal levels. Arrhythmogenesis could be explored during normal pacing activity, regular stimulation, following imposed extra-stimuli, or during progressively incremented steady pacing frequencies. Arrhythmic substrate was identified with temporal and spatial functional heterogeneities predisposing to reentrant excitation phenomena. These could arise from abnormalities in cardiac pacing function, tissue electrical connectivity, and cellular excitation and recovery. Triggering events during or following recovery from action potential excitation could thereby lead to sustained arrhythmia. These surface membrane processes were modified by alterations in cellular Ca2+ homeostasis and energetics, as well as cellular and tissue structural change. Study of murine systems thus offers major insights into both our understanding of normal cardiac activity and its propagation, and their relationship to mechanisms generating clinical arrhythmias. PMID:27974512

Comparative clinical study of a subepithelial connective tissue graft and acellular dermal matrix graft for the treatment of gingival recessions: six- to 12-month changes.

PubMed

de Souza, Sérgio Luís Scombatti; Novaes, Arthur Belém; Grisi, Daniela Corrêa; Taba, Mário; Grisi, Márcio Fernando de Moraes; de Andrade, Patrícia Freitas

2008-07-01

Different techniques have been proposed for the treatment of gingival recession. This study compared the clinical results of gingival recession treatment using a subepithelial connective tissue graft and an acellular dermal matrix allograft. Seven patients with bilateral Miller class I or II gingival recession were selected. Twenty-six recessions were treated and randomly assigned to the test group. In each case the contralateral recession was assigned to the control group. In the control group, a connective tissue graft in combination with a coronally positioned flap was used; in the test group, an acellular dermal matrix allograft was used as a substitute for palatal donor tissue. Probing depth, clinical attachment level, gingival recession, and width of keratinized tissue were measured two weeks prior to surgery and at six and 12 months post-surgery. There were no statistically significant differences between the groups in terms of recession reduction, clinical attachment gain, probing pocket depth, and increase in the width of the keratinized tissue after six or 12 months. There was no statistically significant increase in the width of keratinized tissue between six and 12 months for either group. Within the limitations of this study, it can be suggested that the acellular dermal matrix allograft may be a substitute for palatal donor tissue in root coverage procedures and that the time required for additional gain in the amount of keratinized tissue may be greater for the acellular dermal matrix than for the connective tissue procedures.

Viscoelastic Properties of Human Tracheal Tissues.

PubMed

Safshekan, Farzaneh; Tafazzoli-Shadpour, Mohammad; Abdouss, Majid; Shadmehr, Mohammad B

2017-01-01

The physiological performance of trachea is highly dependent on its mechanical behavior, and therefore, the mechanical properties of its components. Mechanical characterization of trachea is key to succeed in new treatments such as tissue engineering, which requires the utilization of scaffolds which are mechanically compatible with the native human trachea. In this study, after isolating human trachea samples from brain-dead cases and proper storage, we assessed the viscoelastic properties of tracheal cartilage, smooth muscle, and connective tissue based on stress relaxation tests (at 5% and 10% strains for cartilage and 20%, 30%, and 40% for smooth muscle and connective tissue). After investigation of viscoelastic linearity, constitutive models including Prony series for linear viscoelasticity and quasi-linear viscoelastic, modified superposition, and Schapery models for nonlinear viscoelasticity were fitted to the experimental data to find the best model for each tissue. We also investigated the effect of age on the viscoelastic behavior of tracheal tissues. Based on the results, all three tissues exhibited a (nonsignificant) decrease in relaxation rate with increasing the strain, indicating viscoelastic nonlinearity which was most evident for cartilage and with the least effect for connective tissue. The three-term Prony model was selected for describing the linear viscoelasticity. Among different models, the modified superposition model was best able to capture the relaxation behavior of the three tracheal components. We observed a general (but not significant) stiffening of tracheal cartilage and connective tissue with aging. No change in the stress relaxation percentage with aging was observed. The results of this study may be useful in the design and fabrication of tracheal tissue engineering scaffolds.

[Three dimensional structure of the connective tissue papillae of the tongue in Suncus murinus].

PubMed

Kobayashi, K; Miyata, K; Iwasaki, S; Takahashi, K

1989-08-01

The surface structure of the connective tissue papillae (CP) of Suncus murinus tongue was observed by SEM after fixing with Karnovsky's fixative and removal of the epithelial cell layer with 3N or 8N HCl. On the surface of the slender conical tongue, there are densely distributed filiform papillae among which fungiform papillae are seen sporadically. A pair of vallate papillae are situated in the posterior region of the tongue. Filiform papillae appear somewhat different externally depending on the dorsal surface of the anterior tongue. At the tip of the tongue, filiform papillae are of a slender conical shape and have a slight depression in the anterior basal portion. The CP of these is seen as a spherical protrusion on which a shallow groove runs in the anteroposterior direction. In the middle region, somewhat large filiform papillae contain CP having one or two small round head-like structures on each spherical protrusion. These head-like structures are increased in number in the posterior region. In the most posterior region of the anterior tongue, there are distributed large filiform papillae having several slender protrusions that surround a basal anterior depression. These large branched filiform papillae have a glove finger like CP. Small conical filiform papillae are distributed in the posterior marginal region of the anterior tongue which have CP of a horse-shoe like protrusion that opens in the anterior direction. Spherical fungiform papillae have CP which are thick columnar in shape with many lateral thin folds running vertically and having a round depression on the top of each. CP of the vallate papillae appear as a beehive like structure.(ABSTRACT TRUNCATED AT 250 WORDS)

An Efficient, Recyclable, and Stable Immobilized Biocatalyst Based on Bioinspired Microcapsules-in-Hydrogel Scaffolds.

PubMed

Zhang, Shaohua; Jiang, Zhongyi; Shi, Jiafu; Wang, Xueyan; Han, Pingping; Qian, Weilun

2016-09-28

Design and preparation of high-performance immobilized biocatalysts with exquisite structures and elucidation of their profound structure-performance relationship are highly desired for green and sustainable biotransformation processes. Learning from nature has been recognized as a shortcut to achieve such an impressive goal. Loose connective tissue, which is composed of hierarchically organized cells by extracellular matrix (ECM) and is recognized as an efficient catalytic system to ensure the ordered proceeding of metabolism, may offer an ideal prototype for preparing immobilized biocatalysts with high catalytic activity, recyclability, and stability. Inspired by the hierarchical structure of loose connective tissue, we prepared an immobilized biocatalyst enabled by microcapsules-in-hydrogel (MCH) scaffolds via biomimetic mineralization in agarose hydrogel. In brief, the in situ synthesized hybrid microcapsules encapsulated with glucose oxidase (GOD) are hierarchically organized by the fibrous framework of agarose hydrogel, where the fibers are intercalated into the capsule wall. The as-prepared immobilized biocatalyst shows structure-dependent catalytic performance. The porous hydrogel permits free diffusion of glucose molecules (diffusion coefficient: ∼6 × 10(-6) cm(2) s(-1), close to that in water) and retains the enzyme activity as much as possible after immobilization (initial reaction rate: 1.5 × 10(-2) mM min(-1)). The monolithic macroscale of agarose hydrogel facilitates the easy recycling of the immobilized biocatalyst (only by using tweezers), which contributes to the nonactivity decline during the recycling test. The fiber-intercalating structure elevates the mechanical stability of the in situ synthesized hybrid microcapsules, which inhibits the leaching and enhances the stability of the encapsulated GOD, achieving immobilization efficiency of ∼95%. This study will, therefore, provide a generic method for the hierarchical organization of (bio)active materials and the rational design of novel (bio)catalysts.

Lymphatic system of the pancreas.

PubMed

O'Morchoe, C C

A network of lymphatic vessels exists within the pancreas. The majority of vessels forming this network lie in the interlobular septa of connective tissue that subdivide the pancreas into lobes and lobules. Peripheral extensions of these interlobular lymphatics can be found within the lobules, but these intralobular lymphatics are relatively sparse. In the main, the intimate relationships of these internal pancreatic lymphatics are with the blood vessels and associated connective tissue. However in random areas, both intra- and interlobular lymphatics come into close relationship with acinar cells. Rarely are there lymphatics associated with islets of Langerhans, and then only where lymphatic vessels in connective tissue septa pass close to a pancreatic lobule that contains an islet at its periphery. Intra- and interlobular lymphatics are similar in structure. Both are thin walled having an endothelial lining and a delicate component of connective tissue. The pattern of interendothelial cell contacts and the sparsity of gaps between adjacent cells suggest that fluid movement through the intracytoplasmic system of vesicles is important in lymph formation in the pancreas. However intercellular transport is also likely to occur by a dynamic process involving fluid movement through dilatations between cells from interstitium to lymphatic lumen. Both exocrine and endocrine secretions of the pancreas may enter thoracic duct lymph directly in pancreatic lymph, but in normal circumstances this route of entry is not quantitatively important. The structural relationships between lymphatics and pancreatic parenchymal cells also make clear that lymph is not a significant pathway for their secretory products. Rather, the arrangement of lymphatics in the pancreas supports the view that lymph is primarily the drainage medium for substances that, for whatever reason, enter the interstitium. In addition, the low flow of lymph compared with that of plasma lends credence to the view that lymph is not a functionally important pathway for endocrine secretions from the pancreas to reach the blood. Both structural and functional evidence suggests that the proper functioning of the lymphatic system is of critical importance in the homeostasis of the pancreas. The lymphatic system of the pancreas, like that in other organs, is essential in the removal of excess fluid from the interstitium. In this sense, the lymphatics may be considered to serve as an overflow, protective, or safety system. When the system is inadequate or its capacity is exceeded, as in inflammation of the pancreas, exocrine secretions entering the interstitium are not cleared and the proteolytic enzymes cause major damage to the tissue. This, in turn, exacerbates the edema, accentuates the inability of lymphatics to drain the fluid, and results in further damage. The fibrosis that ensues damages the lymphatics either directly or through stricture of the surrounding connective tissue. In consequence, they become inadequate at an even earlier stage in subsequent attacks of inflammation and thereby predispose to chronic and recurrent pancreatitis. The larger interlobular lymphatics formed by the junction of their tributaries emerge upon the surface of the pancreas. There they travel primarily with blood vessels and stream toward a ring of lymph nodes that intimately surrounds the pancreas. A second system of nodes extensively involved in drainage from the pancreas is related to the front and sides of the aorta from the level of the celiac trunk to the origin of the superior mesenteric artery. This second set of nodes receives lymph either directly from the pancreas or indirectly from the first echelon of nodes that rings the organ. Although there is general agreement on the disposition of the groups within these sets of nodes, confusion results from the different classifications used by various authors. These classifications range from being purely descriptive, through an alpha and num

Parcellation of the human substantia nigra based on anatomical connectivity to the striatum☆

PubMed Central

Chowdhury, Rumana; Lambert, Christian; Dolan, Raymond J.; Düzel, Emrah

2013-01-01

Substantia nigra/ventral tegmental area (SN/VTA) subregions, defined by dopaminergic projections to the striatum, are differentially affected by health (e.g. normal aging) and disease (e.g. Parkinson's disease). This may have an impact on reward processing which relies on dopaminergic regions and circuits. We acquired diffusion tensor imaging (DTI) with probabilistic tractography in 30 healthy older adults to determine whether subregions of the SN/VTA could be delineated based on anatomical connectivity to the striatum. We found that a dorsomedial region of the SN/VTA preferentially connected to the ventral striatum whereas a more ventrolateral region connected to the dorsal striatum. These SN/VTA subregions could be characterised by differences in quantitative structural imaging parameters, suggesting different underlying tissue properties. We also observed that these connectivity patterns differentially mapped onto reward dependence personality trait. We show that tractography can be used to parcellate the SN/VTA into anatomically plausible and behaviourally meaningful compartments, an approach that may help future studies to provide a more fine-grained synopsis of pathological changes in the dopaminergic midbrain and their functional impact. PMID:23684858

Breast reconstruction in the high risk patient with systemic connective tissue disease: a case series.

PubMed

Chin, K Y; Chalmers, C R; Bryson, A V; Weiler-Mithoff, E M

2013-01-01

The presence of severe underlying connective tissue disease may restrict the reconstructive options offered to a woman in the event of mastectomy. Putative concerns about reconstructive surgery include the effects of connective tissue disease and immunosuppression on wound healing and donor site morbidity, and increased risks of deranged clotting and thrombophilia after free tissue transfer. There is also the possibility of an unpredictable tissue reaction after oncological resection surgery and adjuvant radiotherapy. Here we present a review of the current sparse evidence regarding reconstructive breast surgery in this challenging group of patients. In addition we present a series of six consecutive patients with a spectrum of connective tissue disorders including combinations of longstanding Systemic Lupus Erythematosis (SLE), Rheumatoid arthritis and Raynaud's Disease who underwent successful post-mastectomy reconstruction with an extended autologous latissimus dorsi flap, along with subsequent successful correction of asymmetry and/or nipple reconstruction. There is a paucity of literature on this subject perhaps suggesting that surgeons are reluctant to offer reconstruction or that uptake is poor in this group. Complications related to radiotherapy and free tissue transfer in patients with severe CTD is less than may be expected. The most common complications experienced by our patients with CTD after extended ALD breast reconstruction were persistent donor site seroma, wound dehiscence and delayed haematoma formation, reflecting the abnormal inflammatory response and deranged haemostatic cascade common to connective tissue disease. However, all six patients made a full recovery from surgery without residual donor site morbidity and with an acceptable aesthetic breast reconstruction. Careful peri-operative management is crucial in this group of patients, but good outcomes are possible using a variety of reconstructive techniques. This is the first reported series of patients with severe connective tissue disease who have been managed with extended ALD breast reconstruction. The majority of complications relate to the donor site but the favourable outcomes demonstrate that the extended ALD flap remains a reliable reconstructive option for this group. Copyright © 2012 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Structure and innervation of the tusk pulp in the African elephant (Loxodonta africana)

PubMed Central

Weissengruber, GE; Egerbacher, M; Forstenpointner, G

2005-01-01

African elephants (Loxodonta africana) use their tusks for digging, carrying and behavioural display. Their healing ability following traumatic injury is enormous. Pain experience caused by dentin or pulp damage of tusks seems to be negligible in elephants. In this study we examined the pulp tissue and the nerve distribution using histology, electron microscopy and immunhistochemistry. The results demonstrate that the pulp comprises two differently structured regions. Randomly orientated collagen fibres characterize a cone-like part lying rostral to the foramen apicis dentis. Numerous nerve fibres and Ruffini endings are found within this cone. Rostral to the cone, delicate collagen fibres and large vessels are orientated longitudinally. The rostral two-thirds of the pulp are highly vascularized, whereas nerve fibres are sparse. Vessel and nerve fibre distribution and the structure of connective tissue possibly play important roles in healing and in the obviously limited pain experience after tusk injuries and pulp alteration. The presence of Ruffini endings is most likely related to the use of tusks as tools. PMID:15817106

Maintenance of a Protein Structure in the Dynamic Evolution of TIMPs over 600 Million Years

PubMed Central

Nicosia, Aldo; Maggio, Teresa; Costa, Salvatore; Salamone, Monica; Tagliavia, Marcello; Mazzola, Salvatore; Gianguzza, Fabrizio; Cuttitta, Angela

2016-01-01

Deciphering the events leading to protein evolution represents a challenge, especially for protein families showing complex evolutionary history. Among them, TIMPs represent an ancient eukaryotic protein family widely distributed in the animal kingdom. They are known to control the turnover of the extracellular matrix and are considered to arise early during metazoan evolution, arguably tuning essential features of tissue and epithelial organization. To probe the structure and molecular evolution of TIMPs within metazoans, we report the mining and structural characterization of a large data set of TIMPs over approximately 600 Myr. The TIMPs repertoire was explored starting from the Cnidaria phylum, coeval with the origins of connective tissue, to great apes and humans. Despite dramatic sequence differences compared with highest metazoans, the ancestral proteins displayed the canonical TIMP fold. Only small structural changes, represented by an α-helix located in the N-domain, have occurred over the evolution. Both the occurrence of such secondary structure elements and the relative solvent accessibility of the corresponding residues in the three-dimensional structures raises the possibility that these sites represent unconserved element prone to accept variations. PMID:26957029

The clinical and pathological characteristics of nephropathies in connective tissue diseases in the Japan Renal Biopsy Registry (J-RBR).

PubMed

Ichikawa, Kazunobu; Konta, Tsuneo; Sato, Hiroshi; Ueda, Yoshihiko; Yokoyama, Hitoshi

2017-12-01

In connective tissue diseases, a wide variety of glomerular, tubulointerstitial, and vascular lesions of the kidney are observed. Nonetheless, recent information is limited regarding renal lesions in connective tissue diseases, except in systemic lupus erythematosus (SLE). In this study, we used a nationwide database of biopsy-confirmed renal diseases in Japan (J-RBR) (UMIN000000618). In total, 20,523 registered patients underwent biopsy between 2007 and 2013; from 110 patients with connective tissue diseases except SLE, we extracted data regarding the clinico-pathological characteristics of the renal biopsy. Our analysis included patients with rheumatoid arthritis (RA) (n = 52), Sjögren's syndrome (SjS) (n = 35), scleroderma (n = 10), mixed connective tissue disease (MCTD; n = 5), anti-phospholipid syndrome (APS; n = 3), polymyositis/dermatomyositis (PM/DM; n = 1), Behçet's disease (n = 1) and others (n = 3). The clinico-pathological features differed greatly depending on the underlying disease. The major clinical diagnosis was nephrotic syndrome in RA; chronic nephritic syndrome with mild proteinuria and reduced renal function in SjS; rapidly progressive nephritic syndrome in scleroderma. The major pathological diagnosis was membranous nephropathy (MN) and amyloidosis in RA; tubulointerstitial nephritis in SjS; proliferative obliterative vasculopathy in scleroderma; MN in MCTD. In RA, most patients with nephrosis were treated using bucillamine, and showed membranous nephropathy. Using the J-RBR database, our study revealed that biopsy-confirmed cases of connective tissue diseases such as RA, SjS, scleroderma, and MCTD show various clinical and pathological characteristics, depending on the underlying diseases and the medication used.

An extended OpenSim knee model for analysis of strains of connective tissues.

PubMed

Marieswaran, M; Sikidar, Arnab; Goel, Anu; Joshi, Deepak; Kalyanasundaram, Dinesh

2018-04-17

OpenSim musculoskeletal models provide an accurate simulation environment that eases limitations of in vivo and in vitro studies. In this work, a biomechanical knee model was formulated with femoral articular cartilages and menisci along with 25 connective tissue bundles representing ligaments and capsules. The strain patterns of the connective tissues in the presence of femoral articular cartilage and menisci in the OpenSim knee model was probed in a first of its kind study. The effect of knee flexion (0°-120°), knee rotation (- 40° to 30°) and knee adduction (- 15° to 15°) on the anterior cruciate, posterior cruciate, medial collateral, lateral collateral ligaments and other connective tissues were studied by passive simulation. Further, a new parameter for assessment of strain namely, the differential inter-bundle strain of the connective tissues were analyzed to provide new insights for injury kinematics. ACL, PCL, LCL and PL was observed to follow a parabolic strain pattern during flexion while MCL represented linear strain patterns. All connective tissues showed non-symmetric parabolic strain variation during rotation. During adduction, the strain variation was linear for the knee bundles except for FL, PFL and TL. Strains higher than 0.1 were observed in most of the bundles during lateral rotation followed by abduction, medial rotation and adduction. In the case of flexion, highest strains were observed in aACL and aPCL. A combination of strains at a flexion of 0° with medial rotation of 30° or a flexion of 80° with rotation of 30° are evaluated as rupture-prone kinematics.

Selective reactivation of human herpesvirus 6 in patients with autoimmune connective tissue diseases.

PubMed

Broccolo, Francesco; Drago, Francesco; Cassina, Giulia; Fava, Andrea; Fusetti, Lisa; Matteoli, Barbara; Ceccherini-Nelli, Luca; Sabbadini, Maria Grazia; Lusso, Paolo; Parodi, Aurora; Malnati, Mauro S

2013-11-01

Viral infections have been associated with autoimmune connective tissue diseases. To evaluate whether active infection by Epstein-Barr virus (EBV), cytomegalovirus (CMV), human herpesvirus (HHV)-6, -7, -8, as well as parvovirus B19 (B19V) occur in patients with autoimmune connective tissue diseases, viral DNA loads were assessed in paired samples of serum and peripheral blood mononuclear cells (PBMCs) of 115 patients affected by different disorders, including systemic sclerosis, systemic, and discoid lupus erythematosus, rheumatoid arthritis, and dermatomyositis. Two additional groups, patients affected by inflammatory diseases (n=51) and healthy subjects (n=58) were studied as controls. The titers of anti-HHV-6 and anti-EBV antibodies were also evaluated. Cell-free HHV-6 serum viremia was detected in a significantly higher proportion of connective tissue diseases patients compared to controls (P<0.0002); a significant association between HHV-6 reactivation and the active disease state was found only for lupus erythematosus (P=0.021). By contrast, the rate of cell-free EBV viremia was similar in patients and controls groups. Cell-free CMV, HHV-8, and B19V viremia was not detected in any subject. Anti-HHV-6 and anti-EBV early antigen IgG titers were both significantly higher in autoimmune diseases patients as compared to healthy controls, although they were not associated with the presence of viremia. EBV, HHV-6, -7 prevalence and viral load in PBMCs of patients with connective tissue diseases and controls were similar. These data suggest that HHV-6 may act as a pathogenic factor predisposing patients to the development of autoimmune connective tissue diseases or, conversely, that these disorders may predispose patients to HHV-6 reactivation. © 2013 Wiley Periodicals, Inc.

Evaluation of human recession defects treated with coronally advanced flaps and either purified recombinant human platelet-derived growth factor-BB with beta tricalcium phosphate or connective tissue: a histologic and microcomputed tomographic examination.

PubMed

McGuire, Michael K; Scheyer, Todd; Nevins, Myron; Schupbach, Peter

2009-02-01

The current study examined the histologic and microcomputed tomographic (micro CT) outcomes of the treatment of gingival recession defects with either a subepithelial connective tissue graft (CTG) or 0.3 mg/mL recombinant human platelet-derived growth factor (rhPDGF-BB) on a beta tricalcium phosphate (beta-TCP) matrix. Gingival recession defects were surgically created in six premolar teeth with no more than 3 mm of keratinized marginal tissue, an osseous crest 2 to 3 mm apical to the newly created gingival margin, and recession depth of at least 3 mm. The defects were left untouched for 2 months; then, four defects were grafted with rhPDGF-BB + beta-TCP + a wound healing dressing, and two defects received CTGs. A coronally advanced flap covered each grafted site. Nine months later, sections were obtained for examination. All four sites treated with rhPDGF-BB + beta-TCP showed connective tissue fibers (Sharpey fibers) perpendicularly inserting into newly formed cementum and alveolar bone. In the two sites treated with CTGs, a long junctional epithelium was seen coronal to the osseous crest and connective tissue fibers ran parallel to the adjacent root surfaces, with no evidence of insertion into cementum or bone. There was no evidence of regeneration of cementum, inserting connective tissue fibers, or supporting alveolar bone. Regeneration of the periodontium in gingival recession defects is possible through growth factor-mediated therapy.

Pluripotent Stem Cells for Retinal Tissue Engineering: Current Status and Future Prospects.

PubMed

Singh, Ratnesh; Cuzzani, Oscar; Binette, François; Sternberg, Hal; West, Michael D; Nasonkin, Igor O

2018-04-19

The retina is a very fine and layered neural tissue, which vitally depends on the preservation of cells, structure, connectivity and vasculature to maintain vision. There is an urgent need to find technical and biological solutions to major challenges associated with functional replacement of retinal cells. The major unmet challenges include generating sufficient numbers of specific cell types, achieving functional integration of transplanted cells, especially photoreceptors, and surgical delivery of retinal cells or tissue without triggering immune responses, inflammation and/or remodeling. The advances of regenerative medicine enabled generation of three-dimensional tissues (organoids), partially recreating the anatomical structure, biological complexity and physiology of several tissues, which are important targets for stem cell replacement therapies. Derivation of retinal tissue in a dish creates new opportunities for cell replacement therapies of blindness and addresses the need to preserve retinal architecture to restore vision. Retinal cell therapies aimed at preserving and improving vision have achieved many improvements in the past ten years. Retinal organoid technologies provide a number of solutions to technical and biological challenges associated with functional replacement of retinal cells to achieve long-term vision restoration. Our review summarizes the progress in cell therapies of retina, with focus on human pluripotent stem cell-derived retinal tissue, and critically evaluates the potential of retinal organoid approaches to solve a major unmet clinical need-retinal repair and vision restoration in conditions caused by retinal degeneration and traumatic ocular injuries. We also analyze obstacles in commercialization of retinal organoid technology for clinical application.

Functional Architecture of the Retina: Development and Disease

PubMed Central

Hoon, Mrinalini; Okawa, Haruhisa; Santina, Luca Della; Wong, Rachel O.L.

2014-01-01

Structure and function are highly correlated in the vertebrate retina, a sensory tissue that is organized into cell layers with microcircuits working in parallel and together to encode visual information. All vertebrate retinas share a fundamental plan, comprising five major neuronal cell classes with cell body distributions and connectivity arranged in stereotypic patterns. Conserved features in retinal design have enabled detailed analysis and comparisons of structure, connectivity and function across species. Each species, however, can adopt structural and/or functional retinal specializations, implementing variations to the basic design in order to satisfy unique requirements in visual function. Recent advances in molecular tools, imaging and electrophysiological approaches have greatly facilitated identification of the cellular and molecular mechanisms that establish the fundamental organization of the retina and the specializations of its microcircuits during development. Here, we review advances in our understanding of how these mechanisms act to shape structure and function at the single cell level, to coordinate the assembly of cell populations, and to define their specific circuitry. We also highlight how structure is rearranged and function is disrupted in disease, and discuss current approaches to re-establish the intricate functional architecture of the retina. PMID:24984227

Functional architecture of the retina: development and disease.

PubMed

Hoon, Mrinalini; Okawa, Haruhisa; Della Santina, Luca; Wong, Rachel O L

2014-09-01

Structure and function are highly correlated in the vertebrate retina, a sensory tissue that is organized into cell layers with microcircuits working in parallel and together to encode visual information. All vertebrate retinas share a fundamental plan, comprising five major neuronal cell classes with cell body distributions and connectivity arranged in stereotypic patterns. Conserved features in retinal design have enabled detailed analysis and comparisons of structure, connectivity and function across species. Each species, however, can adopt structural and/or functional retinal specializations, implementing variations to the basic design in order to satisfy unique requirements in visual function. Recent advances in molecular tools, imaging and electrophysiological approaches have greatly facilitated identification of the cellular and molecular mechanisms that establish the fundamental organization of the retina and the specializations of its microcircuits during development. Here, we review advances in our understanding of how these mechanisms act to shape structure and function at the single cell level, to coordinate the assembly of cell populations, and to define their specific circuitry. We also highlight how structure is rearranged and function is disrupted in disease, and discuss current approaches to re-establish the intricate functional architecture of the retina. Copyright © 2014 Elsevier Ltd. All rights reserved.

Interdisciplinary approach to enhance the esthetics of maxillary anterior region using soft- and hard-tissue ridge augmentation in conjunction with a fixed partial prosthesis.

PubMed

Khetarpal, Shaleen; Chouksey, Ajay; Bele, Anand; Vishnoi, Rahul

2018-01-01

Favorable esthetics is one of the most important treatment outcomes in dentistry, and to achieve this, interdisciplinary approaches are often required. Ridge deficiencies can be corrected for both, soft- and hard-tissue discrepancies. To overcome such defects, not only a variety of prosthetic options are at our disposal but also several periodontal plastic surgical techniques are available as well. Various techniques have been described and revised, over the year to correct ridge defects. For enhancing soft-tissue contours in the anterior region, the subepithelial connective tissue graft is the treatment of choice. A combination of alloplastic bone graft in adjunct to connective tissue graft optimizes ridge augmentation and minimizes defects. The present case report describes the use of vascular interpositional connective tissue graft in combination with alloplastic bone graft for correction of Seibert's Class III ridge deficiency followed by a fixed partial prosthesis to achieve a better esthetic outcome.

Interdisciplinary approach to enhance the esthetics of maxillary anterior region using soft- and hard-tissue ridge augmentation in conjunction with a fixed partial prosthesis

PubMed Central

Khetarpal, Shaleen; Chouksey, Ajay; Bele, Anand; Vishnoi, Rahul

2018-01-01

Favorable esthetics is one of the most important treatment outcomes in dentistry, and to achieve this, interdisciplinary approaches are often required. Ridge deficiencies can be corrected for both, soft- and hard-tissue discrepancies. To overcome such defects, not only a variety of prosthetic options are at our disposal but also several periodontal plastic surgical techniques are available as well. Various techniques have been described and revised, over the year to correct ridge defects. For enhancing soft-tissue contours in the anterior region, the subepithelial connective tissue graft is the treatment of choice. A combination of alloplastic bone graft in adjunct to connective tissue graft optimizes ridge augmentation and minimizes defects. The present case report describes the use of vascular interpositional connective tissue graft in combination with alloplastic bone graft for correction of Seibert's Class III ridge deficiency followed by a fixed partial prosthesis to achieve a better esthetic outcome. PMID:29568176

Deep nuclear invaginations are linked to cytoskeletal filaments - integrated bioimaging of epithelial cells in 3D culture.

PubMed

Jorgens, Danielle M; Inman, Jamie L; Wojcik, Michal; Robertson, Claire; Palsdottir, Hildur; Tsai, Wen-Ting; Huang, Haina; Bruni-Cardoso, Alexandre; López, Claudia S; Bissell, Mina J; Xu, Ke; Auer, Manfred

2017-01-01

The importance of context in regulation of gene expression is now an accepted principle; yet the mechanism by which the microenvironment communicates with the nucleus and chromatin in healthy tissues is poorly understood. A functional role for nuclear and cytoskeletal architecture is suggested by the phenotypic differences observed between epithelial and mesenchymal cells. Capitalizing on recent advances in cryogenic techniques, volume electron microscopy and super-resolution light microscopy, we studied human mammary epithelial cells in three-dimensional (3D) cultures forming growth-arrested acini. Intriguingly, we found deep nuclear invaginations and tunnels traversing the nucleus, encasing cytoskeletal actin and/or intermediate filaments, which connect to the outer nuclear envelope. The cytoskeleton is also connected both to other cells through desmosome adhesion complexes and to the extracellular matrix through hemidesmosomes. This finding supports a physical and/or mechanical link from the desmosomes and hemidesmosomes to the nucleus, which had previously been hypothesized but now is visualized for the first time. These unique structures, including the nuclear invaginations and the cytoskeletal connectivity to the cell nucleus, are consistent with a dynamic reciprocity between the nucleus and the outside of epithelial cells and tissues. © 2017. Published by The Company of Biologists Ltd.

Soft Tissue Closure of Grafted Extraction Sockets in the Anterior Maxilla: A Modified Palatal Pedicle Connective Tissue Flap Technique.

PubMed

El Chaar, Edgard; Oshman, Sarah; Cicero, Giuseppe; Castano, Alejandro; Dinoi, Cinzia; Soltani, Leila; Lee, Yoonjung Nicole

Localized ridge resorption, the consequence of socket collapse, following tooth extraction in the anterior maxilla can adversely affect esthetics, function, and future implant placement. Immediate grafting of extraction sockets may help preserve natural ridge contours, but a lack of available soft tissue can compromise the final esthetic outcome. The presented modified rotated palatal pedicle connective tissue flap is a useful technique for simultaneous soft tissue coverage and augmentation of grafted sockets to improve esthetic outcome. This article delineates its advantages through the presentation of a four-case series using this new technique.

Eyeing the Cyr61/CTGF/NOV (CCN) group of genes in development and diseases: highlights of their structural likenesses and functional dissimilarities.

PubMed

Krupska, Izabela; Bruford, Elspeth A; Chaqour, Brahim

2015-09-23

"CCN" is an acronym referring to the first letter of each of the first three members of this original group of mammalian functionally and phylogenetically distinct extracellular matrix (ECM) proteins [i.e., cysteine-rich 61 (CYR61), connective tissue growth factor (CTGF), and nephroblastoma-overexpressed (NOV)]. Although "CCN" genes are unlikely to have arisen from a common ancestral gene, their encoded proteins share multimodular structures in which most cysteine residues are strictly conserved in their positions within several structural motifs. The CCN genes can be subdivided into members developmentally indispensable for embryonic viability (e.g., CCN1, 2 and 5), each assuming unique tissue-specific functions, and members not essential for embryonic development (e.g., CCN3, 4 and 6), probably due to a balance of functional redundancy and specialization during evolution. The temporo-spatial regulation of the CCN genes and the structural information contained within the sequences of their encoded proteins reflect diversity in their context and tissue-specific functions. Genetic association studies and experimental anomalies, replicated in various animal models, have shown that altered CCN gene structure or expression is associated with "injury" stimuli--whether mechanical (e.g., trauma, shear stress) or chemical (e.g., ischemia, hyperglycemia, hyperlipidemia, inflammation). Consequently, increased organ-specific susceptibility to structural damages ensues. These data underscore the critical functions of CCN proteins in the dynamics of tissue repair and regeneration and in the compensatory responses preceding organ failure. A better understanding of the regulation and mode of action of each CCN member will be useful in developing specific gain- or loss-of-function strategies for therapeutic purposes.

[Technical peculiarities of the argon-plasma welding of gastrointestinal walls wounds in experimental environment].

PubMed

Terekhov, G V; Furmanov, Iu A; Gvozdetskiĭ, V S; Savitskaia, I M

2008-06-01

A new method of the live biological tissues connection, using thermal energy of a high-temperature argon plasma, constituting perspective trend of application of a new nonsuture methods of the tissues connection, original for the world practice, was elaborated in the Department of Experimental Surgery together with the Institute of welding named after Academician E. O. Paton NAS of Ukraine. The argon-plasma welding application secure safe adhesion of the connecting surfaces formation due to the protein complexes temperature denaturation occurrence. The absence of foreign bodies in the connection zone as well as the presence of the plasma flow bacterocidal properties secure, while application of this new method, a significant lowering of a bacterial soiling of the formatted anastomoses, not interfering with the tissue natural regeneration process course.

Cartilage tissue engineering: From biomaterials and stem cells to osteoarthritis treatments.

PubMed

Vinatier, C; Guicheux, J

2016-06-01

Articular cartilage is a non-vascularized and poorly cellularized connective tissue that is frequently damaged as a result of trauma and degenerative joint diseases such as osteoarthrtis. Because of the absence of vascularization, articular cartilage has low capacity for spontaneous repair. Today, and despite a large number of preclinical data, no therapy capable of restoring the healthy structure and function of damaged articular cartilage is clinically available. Tissue-engineering strategies involving the combination of cells, scaffolding biomaterials and bioactive agents have been of interest notably for the repair of damaged articular cartilage. During the last 30 years, cartilage tissue engineering has evolved from the treatment of focal lesions of articular cartilage to the development of strategies targeting the osteoarthritis process. In this review, we focus on the different aspects of tissue engineering applied to cartilage engineering. We first discuss cells, biomaterials and biological or environmental factors instrumental to the development of cartilage tissue engineering, then review the potential development of cartilage engineering strategies targeting new emerging pathogenic mechanisms of osteoarthritis. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

FOXO1 expression in keratinocytes promotes connective tissue healing

PubMed Central

Zhang, Chenying; Lim, Jason; Liu, Jian; Ponugoti, Bhaskar; Alsadun, Sarah; Tian, Chen; Vafa, Rameen; Graves, Dana T.

2017-01-01

Wound healing is complex and highly orchestrated. It is well appreciated that leukocytes, particularly macrophages, are essential for inducing the formation of new connective tissue, which requires the generation of signals that stimulate mesenchymal stem cells (MSC), myofibroblasts and fibroblasts. A key role for keratinocytes in this complex process has yet to be established. To this end, we investigated possible involvement of keratinocytes in connective tissue healing. By lineage-specific deletion of the forkhead box-O 1 (FOXO1) transcription factor, we demonstrate for the first time that keratinocytes regulate proliferation of fibroblasts and MSCs, formation of myofibroblasts and production of collagen matrix in wound healing. This stimulation is mediated by a FOXO1 induced TGFβ1/CTGF axis. The results provide direct evidence that epithelial cells play a key role in stimulating connective tissue healing through a FOXO1-dependent mechanism. Thus, FOXO1 and keratinocytes may be an important therapeutic target where healing is deficient or compromised by a fibrotic outcome. PMID:28220813

Development and Tissue Origins of the Mammalian Cranial Base

PubMed Central

Iseki, S.; Bamforth, S. D.; Olsen, B. R.; Morriss-Kay, G. M.

2008-01-01

The vertebrate cranial base is a complex structure composed of bone, cartilage and other connective tissues underlying the brain; it is intimately connected with development of the face and cranial vault. Despite its central importance in craniofacial development, morphogenesis and tissue origins of the cranial base have not been studied in detail in the mouse, an important model organism. We describe here the location and time of appearance of the cartilages of the chondrocranium. We also examine the tissue origins of the mouse cranial base using a neural crest cell lineage cell marker, Wnt1-Cre/R26R, and a mesoderm lineage cell marker, Mesp1-Cre/R26R. The chondrocranium develops between E11 and E16 in the mouse, beginning with development of the caudal (occipital) chondrocranium, followed by chondrogenesis rostrally to form the nasal capsule, and finally fusion of these two parts via the midline central stem and the lateral struts of the vault cartilages. X-Gal staining of transgenic mice from E8.0 to 10 days post-natal showed that neural crest cells contribute to all of the cartilages that form the ethmoid, presphenoid, and basisphenoid bones with the exception of the hypochiasmatic cartilages. The basioccipital bone and non-squamous parts of the temporal bones are mesoderm derived. Therefore the prechordal head is mostly composed of neural crest-derived tissues, as predicted by the New Head Hypothesis. However, the anterior location of the mesoderm-derived hypochiasmatic cartilages, which are closely linked with the extra-ocular muscles, suggests that some tissues associated with the visual apparatus may have evolved independently of the rest of the “New Head”. PMID:18680740

One-time versus repeated abutment connection for platform-switched implant: A systematic review and meta-analysis

PubMed Central

Wang, Qing-qing; Dai, Ruoxi; Cao, Chris Ying; Fang, Hui; Han, Min; Li, Quan-Li

2017-01-01

Objective This review aims to compare peri-implant tissue changes in terms of clinical and radiographic aspects of implant restoration protocol using one-time abutment to repeated abutment connection in platform switched implant. Method A structured search strategy was applied to three electronic databases, namely, Pubmed, Embase and Web of Science. Eight eligible studies, including seven randomised controlled studies and one controlled clinical study, were identified in accordance with inclusion/exclusion criteria. Outcome measures included peri-implant bone changes (mm), peri-implant soft tissue changes (mm), probing depth (mm) and postsurgical complications. Result Six studies were pooled for meta-analysis on bone tissue, three for soft tissue, two for probing depth and four for postsurgical complications. A total of 197 implants were placed in one-time abutment group, whereas 214 implants were included in repeated abutment group. The implant systems included Global implants, Ankylos, JDEvolution (JdentalCare), Straumann Bone level and Conelog-Screwline. One-time abutment group showed significantly better outcomes than repeated abutment group, as measured in the standardised differences in mean values (fixed- and random-effect model): vertical bone change (0.41, 3.23) in 6 months, (1.51, 14.81) in 12 months and (2.47, 2.47) in 3 years and soft tissue change (0.21, 0.23). No significant difference was observed in terms of probing depth and complications. Conclusion Our meta-analysis revealed that implant restoration protocol using one-time abutment is superior to repeated abutment for platform switched implant because of less bone resorption and soft tissue shifts in former. However, future randomised clinical trials should be conducted to further confirm these findings because of the small samples and the limited quality of the original research. PMID:29049323

One-time versus repeated abutment connection for platform-switched implant: A systematic review and meta-analysis.

PubMed

Wang, Qing-Qing; Dai, Ruoxi; Cao, Chris Ying; Fang, Hui; Han, Min; Li, Quan-Li

2017-01-01

This review aims to compare peri-implant tissue changes in terms of clinical and radiographic aspects of implant restoration protocol using one-time abutment to repeated abutment connection in platform switched implant. A structured search strategy was applied to three electronic databases, namely, Pubmed, Embase and Web of Science. Eight eligible studies, including seven randomised controlled studies and one controlled clinical study, were identified in accordance with inclusion/exclusion criteria. Outcome measures included peri-implant bone changes (mm), peri-implant soft tissue changes (mm), probing depth (mm) and postsurgical complications. Six studies were pooled for meta-analysis on bone tissue, three for soft tissue, two for probing depth and four for postsurgical complications. A total of 197 implants were placed in one-time abutment group, whereas 214 implants were included in repeated abutment group. The implant systems included Global implants, Ankylos, JDEvolution (JdentalCare), Straumann Bone level and Conelog-Screwline. One-time abutment group showed significantly better outcomes than repeated abutment group, as measured in the standardised differences in mean values (fixed- and random-effect model): vertical bone change (0.41, 3.23) in 6 months, (1.51, 14.81) in 12 months and (2.47, 2.47) in 3 years and soft tissue change (0.21, 0.23). No significant difference was observed in terms of probing depth and complications. Our meta-analysis revealed that implant restoration protocol using one-time abutment is superior to repeated abutment for platform switched implant because of less bone resorption and soft tissue shifts in former. However, future randomised clinical trials should be conducted to further confirm these findings because of the small samples and the limited quality of the original research.

Genipin crosslinker releasing sutures for improving the mechanical/repair strength of damaged connective tissue.

PubMed

Sundararaj, Sharath; Slusarewicz, Paul; Brown, Matt; Hedman, Thomas

2017-11-01

The most common mode of surgical repair of ruptured tendons and ligaments involves the use of sutures for reattachment. However, there is a high incidence of rerupture and repair failure due to pulling out of the suture material from the damaged connective tissue. The main goal of this research was to achieve a localized delivery of crosslinking agent genipin (GP) from rapid-release biodegradable coatings on sutures, for strengthening the repair of ruptured connective tissue. Our hypothesis is that GP released from the suture coating will lead to exogenous crosslinking of native connective tissue resulting in beneficial effects on clinically relevant mechanical parameters such as tear resistance, tissue strength, and energy required to rupture the tissue (toughness). Sutures were successfully coated with a biodegradable polymer layer loaded with the crosslinking agent genipin, without compromising the mechanical properties of the suture. The rapid-release of genipin was achieved under both in vitro and ex vivo conditions. Exogenous crosslinking using these genipin releasing sutures was demonstrated using equine tendons. The tendons treated with genipin releasing sutures showed significant improvement in failure load, energy required for pull-out failure, and stiffness. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2199-2205, 2017. © 2016 Wiley Periodicals, Inc.

Lysyl oxidase expression is decreased in the developing diaphragm and lungs of nitrofen-induced congenital diaphragmatic hernia.

PubMed

Takahashi, Toshiaki; Friedmacher, Florian; Takahashi, Hiromizu; Daniel Hofmann, Alejandro; Puri, Prem

2015-02-01

Malformation of the nonmuscular tissue components in congenital diaphragmatic hernia (CDH) is thought to underlie the diaphragmatic defect, causing intrathoracic herniation of abdominal viscera and thus disturbing normal lung development. It has been shown that diaphragmatic and pulmonary morphogeneses require the structural integrity of connective tissue, and developmental mutations that inhibit the formation of extracellular matrix (ECM) result in CDH with hypoplastic lungs. Lysyl oxidase (lox), an extracellular enzyme that catalyzes the cross-linking of ECM proteins, plays an essential role during diaphragmatic and pulmonary development by controlling the formation of connective tissue. Furthermore, lox (-/-) knockouts exhibit abnormal connective tissue with diaphragmatic defects and impaired airway morphogenesis. We designed this study to investigate the hypothesis that diaphragmatic and pulmonary lox expression is decreased in the nitrofen-induced CDH model. Timed-pregnant Sprague-Dawley rats were exposed to either nitrofen or vehicle on gestational day 9 (D9), and fetuses were harvested on selected time points D15 and D18. The micro-dissected fetal diaphragms (n=48) and lungs (n=48) were divided into two groups: control and nitrofen-exposed samples (n=12 per specimen and time point, respectively). Diaphragmatic and pulmonary gene expression levels of lox were analyzed by quantitative real-time polymerase chain reaction. Immunohistochemical staining was performed to evaluate lox protein expression in diaphragms and lungs. Relative mRNA expression of lox was significantly reduced in diaphragms and lungs of nitrofen-exposed fetuses on D15 (0.29 ± 0.08 vs. 0.12 ± 0.05; p<0.05 and 0.52 ± 0.44 vs. 0.20 ± 0.04; p<0.05) and D18 (0.90 ± 0.25 vs. 0.57 ± 0.23; p<0.05 and 0.59 ± 0.26 vs. 0.35 ± 0.09; p<0.05) compared with controls. Diaphragmatic and pulmonary immunoreactivity of lox was markedly decreased in nitrofen-exposed fetuses on D15 and D18 compared with controls. Decreased lox expression during diaphragmatic development and lung branching morphogenesis may interfere with normal cross-linking of ECM proteins, disrupting the integrity of connective tissue, and contributing to the diaphragmatic defect and impaired airway formation in the nitrofen-induced CDH model. Georg Thieme Verlag KG Stuttgart · New York.

Sodium Chloride Diffusion during Muscle Salting Evidenced by Energy-Dispersive X-ray Spectroscopy Imaging.

PubMed

Filgueras, Rénata; Peyrin, Frédéric; Vénien, Annie; Hénot, Jean Marc; Astruc, Thierry

2016-01-27

To better understand the relationship between the muscle structure and NaCl transfers in meat, we used energy-dispersive X-ray spectroscopy (EDS) coupled with scanning electron microscopy (SEM) to analyze brined and dry-salted rat muscles. The muscles were freeze-dried to avoid the delocalization of soluble ions that happens in regular dehydration through a graded series of ethanol. Na and Cl maps were superimposed on SEM images to combine the muscle structure and NaCl diffusion. Brining causes rapid diffusion of NaCl through the tissue. Most brine diffuses in a linear front from the muscle surface, but a small proportion enters through the perimysium network. The muscle area penetrated by brine shows heterogeneous patterns of NaCl retention, with some connective tissue islets containing more NaCl than other parts of perimysium. NaCl penetration is considerably slower after dry salting than after brining.

Refuting The Polemic Against the Extraocular Muscle Pulleys: Jampel and Shi’s Platygean View of Extraocular Muscle Mechanics

PubMed Central

Demer, Joseph L.

2007-01-01

Background Late in the 20th Century, it was recognized that connective tissue structures in the orbit influence the paths of the extraocular muscles, and constitute their functional origins. Targeted investigations of these connective tissue “pulleys” led to the formulation of the active pulley hypothesis, which proposes that pulling directions of the rectus extraocular muscles are actively controlled via connective tissues. Purpose This review rebuts a series of criticisms of the active pulley hypothesis published by Jampel, and Jampel and Shi, in which these authors have disputed the existence and function of the pulleys. Methods The current paper reviews published evidence for the existence of orbital pulleys, the active pulley hypothesis, and physiologic tests of the active pulley hypothesis. Magnetic resonance imaging in a living subject, and histological examination of a human cadaver directly illustrate the relationship of pulleys to extraocular muscles. Results Strong scientific evidence is cited that supports the existence of orbital pulleys, and their role in ocular motility. The criticisms of have ignored mathematical truisms and strong scientific evidence. Conclusions Actively controlled orbital pulleys play a fundamental role in ocular motility. Pulleys profoundly influence the neural commands required to control eye movements and binocular alignment. Familiarity with the anatomy and physiology of the pulleys is requisite for a rational approach to diagnosing and treating strabismus using emerging methods. Conversely, approaches that deny or ignore the pulleys risk the sorts of errors that arise in geography and navigation from incorrect assumptions such as those of a flat (“platygean”) earth. PMID:17022164

Histopathology of lung disease in the connective tissue diseases.

PubMed

Vivero, Marina; Padera, Robert F

2015-05-01

The pathologic correlates of interstitial lung disease (ILD) secondary to connective tissue disease (CTD) comprise a diverse group of histologic patterns. Lung biopsies in patients with CTD-associated ILD tend to demonstrate simultaneous involvement of multiple anatomic compartments of the lung. Certain histologic patterns tend to predominate in each defined CTD, and it is possible in many cases to confirm connective tissue-associated lung disease and guide patient management using surgical lung biopsy. This article will cover the pulmonary pathologies seen in rheumatoid arthritis, systemic sclerosis, myositis, systemic lupus erythematosus, Sjögren syndrome, and mixed CTD. Copyright © 2015 Elsevier Inc. All rights reserved.

Elasticity Imaging of Polymeric Media

PubMed Central

Sridhar, Mallika; Liu, Jie; Insana, Michael F.

2009-01-01

Viscoelastic properties of soft tissues and hydropolymers depend on the strength of molecular bonding forces connecting the polymer matrix and surrounding fluids. The basis for diagnostic imaging is that disease processes alter molecular-scale bonding in ways that vary the measurable stiffness and viscosity of the tissues. This paper reviews linear viscoelastic theory as applied to gelatin hydrogels for the purpose of formulating approaches to molecular-scale interpretation of elasticity imaging in soft biological tissues. Comparing measurements acquired under different geometries, we investigate the limitations of viscoelastic parameters acquired under various imaging conditions. Quasistatic (step-and-hold and low-frequency harmonic) stimuli applied to gels during creep and stress relaxation experiments in confined and unconfined geometries reveal continuous, bimodal distributions of respondance times. Within the linear range of responses, gelatin will behave more like a solid or fluid depending on the stimulus magnitude. Gelatin can be described statistically from a few parameters of low-order rheological models that form the basis of viscoelastic imaging. Unbiased estimates of imaging parameters are obtained only if creep data are acquired for greater than twice the highest retardance time constant and any steady-state viscous response has been eliminated. Elastic strain and retardance time images are found to provide the best combination of contrast and signal strength in gelatin. Retardance times indicate average behavior of fast (1–10 s) fluid flows and slow (50–400 s) matrix restructuring in response to the mechanical stimulus. Insofar as gelatin mimics other polymers, such as soft biological tissues, elasticity imaging can provide unique insights into complex structural and biochemical features of connectives tissues affected by disease. PMID:17408331

Interpretation of measurements of dynamic fluorescence of the eye

NASA Astrophysics Data System (ADS)

Schweitzer, Dietrich; Hammer, Martin; Jentsch, Susanne; Schenke, Stefan

2007-09-01

First pathological alterations occur at cellular level, most in metabolism. An indirect estimation of metabolic activity in cells is measurement of microcirculation. Measurements of tissue autofluorescence are potentially suited for direct investigation of cellular metabolism. Besides redox pairs of co-enzymes (NADH-NAD, FADH2-FAD) several other fluorophores are excited in tissue. In addition, a number of anatomical structures are simultaneously excited, when investigating the eye-ground. In this study, spectral and time resolved comparison was performed between purified substances, single ocular structures and in vivo measurements of the time-resolved autofluorescence at the human eye. In human eyes, the ageing pigment lipofuscin covers other fluorophores at the fundus in long - wave visible range. Applying lifetime measurements, weakly emitting fluorophores can be detected, when the lifetimes are different from the strongly emitting fluorophore. For this, the autofluorescence was excited at 468 nm and detected in two spectral ranges (500 nm-560 nm, 560 nm-700 nm). In tri-exponential fitting, the short lifetime corresponds to retinal pigment epithelium, the mean lifetime corresponds probably to neural retina and the long lifetime is caused by fluorescence of connective tissue.

High-resolution, anthropomorphic, computational breast phantom: fusion of rule-based structures with patient-based anatomy

NASA Astrophysics Data System (ADS)

Chen, Xinyuan; Gong, Xiaolin; Graff, Christian G.; Santana, Maira; Sturgeon, Gregory M.; Sauer, Thomas J.; Zeng, Rongping; Glick, Stephen J.; Lo, Joseph Y.

2017-03-01

While patient-based breast phantoms are realistic, they are limited by low resolution due to the image acquisition and segmentation process. The purpose of this study is to restore the high frequency components for the patient-based phantoms by adding power law noise (PLN) and breast structures generated based on mathematical models. First, 3D radial symmetric PLN with β=3 was added at the boundary between adipose and glandular tissue to connect broken tissue and create a high frequency contour of the glandular tissue. Next, selected high-frequency features from the FDA rule-based computational phantom (Cooper's ligaments, ductal network, and blood vessels) were fused into the phantom. The effects of enhancement in this study were demonstrated by 2D mammography projections and digital breast tomosynthesis (DBT) reconstruction volumes. The addition of PLN and rule-based models leads to a continuous decrease in β. The new β is 2.76, which is similar to what typically found for reconstructed DBT volumes. The new combined breast phantoms retain the realism from segmentation and gain higher resolution after restoration.

Two-photon excitation based photochemistry and neural imaging

NASA Astrophysics Data System (ADS)

Hatch, Kevin Andrew

Two-photon microscopy is a fluorescence imaging technique which provides distinct advantages in three-dimensional cellular and molecular imaging. The benefits of this technology may extend beyond imaging capabilities through exploitation of the quantum processes responsible for fluorescent events. This study utilized a two-photon microscope to investigate a synthetic photoreactive collagen peptidomimetic, which may serve as a potential material for tissue engineering using the techniques of two-photon photolysis and two-photon polymerization. The combination of these techniques could potentially be used to produce a scaffold for the vascularization of engineered three-dimensional tissues in vitro to address the current limitations of tissue engineering. Additionally, two-photon microscopy was used to observe the effects of the application of the neurotransmitter dopamine to the mushroom body neural structures of Drosophila melanogaster to investigate dopamine's connection to cognitive degeneration.

Connective tissue grafts for thickening peri-implant tissues at implant placement. One-year results from an explanatory split-mouth randomised controlled clinical trial.

PubMed

Wiesner, Günter; Esposito, Marco; Worthington, Helen; Schlee, Markus

2010-01-01

Nothing to declare. To evaluate whether connective tissue grafts performed at implant placement could be effective in augmenting peri-implant soft tissues. Ten partially edentulous patients requiring at least one single implant in the premolar or molar areas of both sides of the mandible were randomised to have one side augmented at implant placement with a connective soft tissue graft harvested from the palate or no augmentation. After 3 months of submerged healing, abutments were placed and within 1 month definitive crowns were permanently cemented. Outcome measures were implant success, any complications, peri-implant marginal bone level changes, patient satisfaction and preference, thickness of the soft tissues and aesthetics (pink aesthetic score) evaluated by an independent and blinded assessor 1 year after loading. One year after loading, no patients dropped out, no implants failed and no complications occurred. Both groups lost statistically significant amounts of peri-implant bone 1 year after loading (0.8 mm in the grafted group and 0.6 mm in the non-grafted group), but there was no statistically significant difference between groups. Soft tissues at augmented sites were 1.3 mm thicker (P < 0.001) and had a significantly better pink aesthetic score (P < 0.001). Patients were highly satisfied (no statistically significant differences between treatments) though they preferred the aesthetics of the augmented sites (P = 0.031). However, five patients would not undergo the grafting procedure again and two were uncertain. Connective tissue grafts are effective in increasing soft tissue thickness, thus improving aesthetics. Longer follow-ups are needed to evaluate the stability of peri-implant tissues over time.

Microstructure alterations in beef intramuscular connective tissue caused by hydrodynamic pressure processing

USDA-ARS?s Scientific Manuscript database

Scanning electron microscopy (SEM) was utilized to evaluate microstructural changes in intramuscular connective tissue of beef semimembranosus muscle subjected to hydrodynamic pressure processing (HDP). Samples were HDP treated in a plastic container (HDP-PC) or a steel commercial unit (HDP-CU). C...

Large-scale tissue clearing (PACT): Technical evaluation and new perspectives in immunofluorescence, histology, and ultrastructure.

PubMed

Neckel, Peter H; Mattheus, Ulrich; Hirt, Bernhard; Just, Lothar; Mack, Andreas F

2016-09-29

Novel techniques, like CLARITY and PACT, render large tissue specimens transparent and thereby suitable for microscopic analysis. We used these techniques to evaluate their potential in the intestine as an exemplary organ with a complex tissue composition. Immunohistochemistry, light sheet-, and confocal scanning-microscopy enabled us to follow complex three-dimensional structures, like nerve fibers, vessels, and epithelial barriers throughout the entire organ. Moreover, in a systematic electron microscopic study, we analyzed the morphology and preservation of tissue on ultrastructural level during the clearing process. We also connect tissue clearing with classical histology and demonstrate that cleared tissues can be stained with Hematoxylin-Eosin and Heidenhain's Azan stain, suggesting potential use in histopathology. These experiments showed that a neutral pH during the clearing process results in much better preservation of tissue ultrastructure and standard stainability. Volume changes of specimens were monitored and quantified during the course of the protocol. Additionally, we employed the technique to visualize the enteric nervous system and the epithelial barrier in post mortem human gut preparations. Our data show the high potential of tissue clearing throughout different tissue types supporting its usefulness in research and diagnosis, and contribute to the technical discussion of ultrastructural tissue-retention.

Large-scale tissue clearing (PACT): Technical evaluation and new perspectives in immunofluorescence, histology, and ultrastructure

PubMed Central

Neckel, Peter H.; Mattheus, Ulrich; Hirt, Bernhard; Just, Lothar; Mack, Andreas F.

2016-01-01

Novel techniques, like CLARITY and PACT, render large tissue specimens transparent and thereby suitable for microscopic analysis. We used these techniques to evaluate their potential in the intestine as an exemplary organ with a complex tissue composition. Immunohistochemistry, light sheet-, and confocal scanning-microscopy enabled us to follow complex three-dimensional structures, like nerve fibers, vessels, and epithelial barriers throughout the entire organ. Moreover, in a systematic electron microscopic study, we analyzed the morphology and preservation of tissue on ultrastructural level during the clearing process. We also connect tissue clearing with classical histology and demonstrate that cleared tissues can be stained with Hematoxylin-Eosin and Heidenhain’s Azan stain, suggesting potential use in histopathology. These experiments showed that a neutral pH during the clearing process results in much better preservation of tissue ultrastructure and standard stainability. Volume changes of specimens were monitored and quantified during the course of the protocol. Additionally, we employed the technique to visualize the enteric nervous system and the epithelial barrier in post mortem human gut preparations. Our data show the high potential of tissue clearing throughout different tissue types supporting its usefulness in research and diagnosis, and contribute to the technical discussion of ultrastructural tissue-retention. PMID:27680942

Dense Breasts

MedlinePlus

... fatty tissue. On a mammogram, fatty tissue appears dark (radio-lucent) and the glandular and connective tissues ... white on mammography) and non-dense fatty tissue (dark on mammography) using a visual scale and assign ...

In-vivo imaging of the palisades of Vogt and the limbal crypts with sub-micrometer axial resolution optical coherence tomography

PubMed Central

Bizheva, Kostadinka; Tan, Bingyao; MacLellan, Benjamin; Hosseinaee, Zohreh; Mason, Erik; Hileeto, Denise; Sorbara, Luigina

2017-01-01

A research-grade OCT system was used to image in-vivo and without contact with the tissue, the cellular structure and microvasculature of the healthy human corneo-scleral limbus. The OCT system provided 0.95 µm axial and 4 µm (2 µm) lateral resolution in biological tissue depending on the magnification of the imaging objective. Cross-sectional OCT images acquired tangentially from the inferior limbus showed reflective, loop-like features that correspond to the fibrous folds of the palisades of Vogt (POV). The high OCT resolution allowed for visualization of individual cells inside the limbal crypts, capillaries extending from the inside of the POV’s fibrous folds and connecting to a lateral grid of micro-vessels located in the connective tissue directly below the POV, as well as reflections from individual red blood cells inside the capillaries. Difference in the reflective properties of the POV was observed among subjects of various pigmentation levels of the POV. Morphological features observed in the high resolution OCT images correlated well with histology. The ability to visualize the limbal morphology and microvasculature in-vivo at cellular level can aid the diagnostics and treatment of limbal stem cell dysfunction and dystrophies. PMID:28966853

Epithelial Patterning, Morphogenesis, and Evolution: Drosophila Eggshell as a Model.

PubMed

Osterfield, Miriam; Berg, Celeste A; Shvartsman, Stanislav Y

2017-05-22

Understanding the mechanisms driving tissue and organ formation requires knowledge across scales. How do signaling pathways specify distinct tissue types? How does the patterning system control morphogenesis? How do these processes evolve? The Drosophila egg chamber, where EGF and BMP signaling intersect to specify unique cell types that construct epithelial tubes for specialized eggshell structures, has provided a tractable system to ask these questions. Work there has elucidated connections between scales of development, including across evolutionary scales, and fostered the development of quantitative modeling tools. These tools and general principles can be applied to the understanding of other developmental processes across organisms. Copyright © 2017 Elsevier Inc. All rights reserved.

Tractography patterns of subthalamic nucleus deep brain stimulation.

PubMed

Vanegas-Arroyave, Nora; Lauro, Peter M; Huang, Ling; Hallett, Mark; Horovitz, Silvina G; Zaghloul, Kareem A; Lungu, Codrin

2016-04-01

Deep brain stimulation therapy is an effective symptomatic treatment for Parkinson's disease, yet the precise mechanisms responsible for its therapeutic effects remain unclear. Although the targets of deep brain stimulation are grey matter structures, axonal modulation is known to play an important role in deep brain stimulation's therapeutic mechanism. Several white matter structures in proximity to the subthalamic nucleus have been implicated in the clinical benefits of deep brain stimulation for Parkinson's disease. We assessed the connectivity patterns that characterize clinically beneficial electrodes in Parkinson's disease patients, after deep brain stimulation of the subthalamic nucleus. We evaluated 22 patients with Parkinson's disease (11 females, age 57 ± 9.1 years, disease duration 13.3 ± 6.3 years) who received bilateral deep brain stimulation of the subthalamic nucleus at the National Institutes of Health. During an initial electrode screening session, one month after deep brain stimulation implantation, the clinical benefits of each contact were determined. The electrode was localized by coregistering preoperative magnetic resonance imaging and postoperative computer tomography images and the volume of tissue activated was estimated from stimulation voltage and impedance. Brain connectivity for the volume of tissue activated of deep brain stimulation contacts was assessed using probabilistic tractography with diffusion-tensor data. Areas most frequently connected to clinically effective contacts included the thalamus, substantia nigra, brainstem and superior frontal gyrus. A series of discriminant analyses demonstrated that the strength of connectivity to the superior frontal gyrus and the thalamus were positively associated with clinical effectiveness. The connectivity patterns observed in our study suggest that the modulation of white matter tracts directed to the superior frontal gyrus and the thalamus is associated with favourable clinical outcomes and may contribute to the therapeutic effects of deep brain stimulation. Our method can be further developed to reliably identify effective deep brain stimulation contacts and aid in the programming process. © The Author (2016). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Clinical Evaluation of Papilla Reconstruction Using Subepithelial Connective Tissue Graft

PubMed Central

Kaushik, Alka; PK, Pal; Chopra, Deepak; Chaurasia, Vishwajit Rampratap; Masamatti, Vinaykumar S; DK, Suresh; Babaji, Prashant

2014-01-01

Objective: The aesthetics of the patient can be improved by surgical reconstruction of interdental papilla by using an advanced papillary flap interposed with subepithelial connective tissue graft. Materials and Methods: A total of fifteen sites from ten patients having black triangles/papilla recession in the maxillary anterior region were selected and subjected to presurgical evaluation. The sites were treated with interposed subepithelial connective tissue graft placed under a coronally advance flap. The integrity of the papilla was maintained by moving the whole of gingivopapillary unit coronally. The various parameters were analysed at different intervals. Results: There was a mean decrease in the papilla presence index score and distance from contact point to gingival margin, but it was statistically not significant. Also, there is increase in the width of the keratinized gingiva which was statistically highly significant. Conclusion: Advanced papillary flap with interposed sub–epithelial connective tissue graft can offer predictable results for the reconstruction of interdental papilla. If papilla loss occurs solely due to soft-tissue damage, reconstructive techniques can completely restore it; but if due to periodontal disease involving bone loss, reconstruction is generally incomplete and multiple surgical procedures may be required. PMID:25386529

[Systemic lupus erythematosus and pregnancy].

PubMed

Basheva, S; Nikolov, A; Stoilov, R; Stoilov, N

2012-01-01

Connective-tissue disorders, also referred to as collagen-vascular disorders, are characterized by autoantibody-mediated connective-tissue abnormalities. These are also called immune-complex diseases because many involve deposition of immune complexes in specific organ or tissue sites. Some of these disorders are characterized by sterile inflammation, especially of the skin, joints, blood vessels, and kidneys, and are referred to as rheumatic diseases. For inexplicable reasons, many rheumatic diseases primarily affect women. Another major category of connective-tissue diseases includes inherited disorders of bone, skin, cartilage, blood vessels. Examples include Marfan syndrome, osteogenesis imperfecta, and Ehlers-Danlos syndrome. Lupus erythematosus (LE) is the main and most important disease in the group of systemic connective tissue diseases. It is heterogeneous, multiple organs autoimmune inflammatory disease with complex pathogenesis, which is the result of interaction between the susceptible genes and environmental factors that lead to abnormal immune response. In this review will consider: its incidence, pathogenesis, clinical forms and clinical features and diagnosis set based on generally accepted clinical criteria developed by the American College of Rheumatology (ACR), the course of pregnancy in patients suffering from LE, the most common complications of LE during pregnancy and antiphospholipid syndrome as part of LE.

Smooth Muscle-Mediated Connective Tissue Remodeling in Pulmonary Hypertension

NASA Astrophysics Data System (ADS)

Mecham, Robert P.; Whitehouse, Loren A.; Wrenn, David S.; Parks, William C.; Griffin, Gail L.; Senior, Robert M.; Crouch, Edmond C.; Stenmark, Kurt R.; Voelkel, Norbert F.

1987-07-01

Abnormal accumulation of connective tissue in blood vessels contributes to alterations in vascular physiology associated with disease states such as hypertension and atherosclerosis. Elastin synthesis was studied in blood vessels from newborn calves with severe pulmonary hypertension induced by alveolar hypoxia in order to investigate the cellular stimuli that elicit changes in pulmonary arterial connective tissue production. A two- to fourfold increase in elastin production was observed in pulmonary artery tissue and medial smooth muscle cells from hypertensive calves. This stimulation of elastin production was accompanied by a corresponding increase in elastin messenger RNA consistent with regulation at the transcriptional level. Conditioned serum harvested from cultures of pulmonary artery smooth muscle cells isolated from hypertensive animals contained one or more low molecular weight elastogenic factors that stimulated the production of elastin in both fibroblasts and smooth muscle cells and altered the chemotactic responsiveness of fibroblasts to elastin peptides. These results suggest that connective tissue changes in the pulmonary vasculature in response to pulmonary hypertension are orchestrated by the medial smooth muscle cell through the generation of specific differentiation factors that alter both the secretory phenotype and responsive properties of surrounding cells.

Composition, Architecture, and Functional Implications of the Connective Tissue Network of the Extraocular Muscles

PubMed Central

McLoon, Linda K.; Vicente, André; Fitzpatrick, Krysta R.; Lindström, Mona

2018-01-01

Purpose We examined the pattern and extent of connective tissue distribution in the extraocular muscles (EOMs) and determined the ability of the interconnected connective tissues to disseminate force laterally. Methods Human EOMs were examined for collagens I, III, IV, and VI; fibronectin; laminin; and elastin using immunohistochemistry. Connective tissue distribution was examined with scanning electron microscopy. Rabbit EOMs were examined for levels of force transmission longitudinally and transversely using in vitro force assessment. Results Collagens I, III, and VI localized to the endomysium, perimysium, and epimysium. Collagen IV, fibronectin, and laminin localized to the basal lamina surrounding all myofibers. All collagens localized similarly in the orbital and global layers throughout the muscle length. Elastin had the most irregular pattern and ran longitudinally and circumferentially throughout the length of all EOMs. Scanning electron microscopy showed these elements to be extensively interconnected, from endomysium through the perimysium to the epimysium surrounding the whole muscle. In vitro physiology demonstrated force generation in the lateral dimension, presumably through myofascial transmission, which was always proportional to the force generated in the longitudinally oriented muscles. Conclusions A striking connective tissue matrix interconnects all the myofibers and extends, via perimysial connections, to the epimysium. These interconnections are significant and allow measurable force transmission laterally as well as longitudinally, suggesting that they may contribute to the nonlinear force summation seen in motor unit recording studies. This provides strong evidence that separate compartmental movements are unlikely as no region is independent of the rest of the muscle. PMID:29346490

Raman microspectroscopy as a diagnostic tool for the non-invasive analysis of fibrillin-1 deficiency in the skin and in the in vitro skin models.

PubMed

Brauchle, Eva; Bauer, Hannah; Fernes, Patrick; Zuk, Alexandra; Schenke-Layland, Katja; Sengle, Gerhard

2017-04-01

Fibrillin microfibrils and elastic fibers are critical determinants of elastic tissues where they define as tissue-specific architectures vital mechanical properties such as pliability and elastic recoil. Fibrillin microfibrils also facilitate elastic fiber formation and support the association of epithelial cells with the interstitial matrix. Mutations in fibrillin-1 (FBN1) are causative for the Marfan syndrome, a congenital multisystem disorder characterized by progressive deterioration of the fibrillin microfibril/ elastic fiber architecture in the cardiovascular, musculoskeletal, ocular, and dermal system. In this study, we utilized Raman microspectroscopy in combination with principal component analysis (PCA) to analyze the molecular consequences of fibrillin-1 deficiency in skin of a mouse model (GT8) of Marfan syndrome. In addition, full-thickness skin models incorporating murine wild-type and Fbn1 GT8/GT8 fibroblasts as well as human HaCaT keratinocytes were generated and analyzed. Skin models containing GT8 fibroblasts showed an altered epidermal morphology when compared to wild-type models indicating a new role for fibrillin-1 in dermal-epidermal crosstalk. Obtained Raman spectra together with PCA allowed to discriminate between healthy and deficient microfibrillar networks in murine dermis and skin models. Interestingly, results obtained from GT8 dermis and skin models showed similar alterations in molecular signatures triggered by fibrillin-1 deficiency such as amide III vibrations and decreased levels of glycan vibrations. Overall, this study indicates that Raman microspectroscopy has the potential to analyze subtle changes in fibrillin-1 microfibrils and elastic fiber networks. Therefore Raman microspectroscopy may be utilized as a non-invasive and sensitive diagnostic tool to identify connective tissue disorders and monitor their disease progression. Mutations in building blocks of the fibrillin microfibril/ elastic fiber network manifest in disease conditions such as aneurysms, emphysema or lax skin. Understanding how structural changes induced by fibrillin-1 mutation impact the architecture of fibrillin microfibrils, which then translates into an altered activation state of targeted growth factors, represents a huge challenge in elucidating the genotype-phenotype correlations in connective tissue disorders such as Marfan syndrome. This study shows that Raman microspectroscopy is able to reveal structural changes in fibrillin-1 microfibrils and elastic fiber networks and to discriminate between normal and diseased networks in vivo and in vitro. Therefore Raman microspectroscopy may be utilized as a non-invasive and sensitive diagnostic tool to identify connective tissue disorders and monitor their disease progression. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Periodontal plastic surgery: thermal effect analysis using Erbium:YAG Kesler's handpiece. Histochemical evaluation by Picrosirius red stain and polarization microscopy for collagen determination: in

NASA Astrophysics Data System (ADS)

Kesler, Gavriel; Koren, Rumelia; Kesler, Anat; Kristt, Don; Gal, Rivka

2000-03-01

Recent technological advances lead to an increase in the options for the treatment of the periodontal diseases. Lasers utilized for gingival soft tissue resurfacing mainly for esthetics purposes, require careful histopathological evaluation of the effects on tissue. Up to date no comparative clinical or histological studies have been performed, aiming at demonstration of the effects of laser irradiation on connective tissue, especially its most important component -- the collagen fibers. The alteration in the structures of this tissue plays the most important role in the healing process. The aim of the present study is to evaluate the influence of Erbium: YAG - Kesler's hand piece on gingival tissue. This handpiece is designed for gingival resurfacing, in cases of 'Gummy smile' and gingival pigmentation. The following irradiation parameters were used: energy per pulse -- 500 mJ, repetition rate 10 pps, spot size 3 mm. Gingival biopsies specimens of 10 patients, 6 with 'Gummy smile' and 4 with gingival pigmentation were examined before laser treatment, and at 7 and 14 days after laser treatment. The tissues were fixed in LNRS, embedded in paraffin, and sectioned into 5 micrometer thickness, dewaxed in xylol and stained with H&E and Picrosirius Red (PSR). The sections were examined by polarization microscopy. PSR is a collagen stain that differentiates collagen fiber density by the range of colors from green through yellow to red, and/or fiber size. This was utilized in the present study to evaluate the hypothesis that Erbium -- YAG (Er: YAG) laser energy is capable of remodeling the collagen fibers in the gingival connective tissue through a photothermal process. We found a significant difference between the structures of collagen fibers at the first week and at 14 days post treatment. In the normal gingiva the predominant polarization colors were in the red-orange range, signifying tightly packed, mature collagen. During the first postoperative week, collagen fibers exhibit mainly polarization colors in the green to green-yellow range implying less packed intermediate collagen fibers. After two weeks, collagen fibers required their preoperative polarizing texture. These findings strongly suggest that the 'quality' rather than the quantity of gingival collagen fibers play an important role in order for collagen shrinkage and reproduction to occur.

Probing multi-scale mechanical damage in connective tissues using X-ray diffraction.

PubMed

Bianchi, Fabio; Hofmann, Felix; Smith, Andrew J; Thompson, Mark S

2016-11-01

The accumulation of microstructural collagen damage following repetitive loading is linked to painful and debilitating tendon injuries. As a hierarchical, semi-crystalline material, collagen mechanics can be studied using X-ray diffraction. The aim of the study was to describe multi-structural changes in tendon collagen following controlled plastic damage (5% permanent strain). We used small angle X-ray scattering (SAXS) to interrogate the spacing of collagen molecules within a fibril, and wide angle X-ray scattering (WAXS) to measure molecular strains under macroscopic loading. Simultaneous recordings of SAXS and WAXS patterns, together with whole-tissue strain in physiologically hydrated rat-tail tendons were made during increments of in situ tensile loading. Results showed that while tissue level modulus was unchanged, fibril modulus decreased significantly, and molecular modulus significantly increased. Further, analysis of higher order SAXS peaks suggested structural changes in the gap and overlap regions, possibly localising the damage to molecular cross-links. Our results provide new insight into the fundamental damage processes at work in collagenous tissues and point to new directions for their mitigation and repair. This article reports the first in situ loading synchrotron studies on mechanical damage in collagenous tissues. We provide new insight into the nano- and micro-structural mechanisms of damage processes. Pre-damaged tendons showed differential alteration of moduli at macro, micro and nano-scales as measured using X-ray scattering techniques. Detailed analysis of higher order diffraction peaks suggested damage is localised to molecular cross-links. The results are consistent with previous X-ray scattering studies of tendons and also with recent thermal stability studies on damaged material. Detailed understanding of damage mechanisms is essential in the development of new therapies promoting tissue repair. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Nanolayered siRNA delivery platforms for local silencing of CTGF reduce cutaneous scar contraction in third-degree burns

PubMed Central

Castleberry, Steven A.; Golberg, Alexander; Sharkh, Malak Abu; Khan, Saiqa; Almquist, Benjamin D.; Austen, William G.; Yarmush, Martin L.; Hammond, Paula T.

2017-01-01

Wound healing is an incredibly complex biological process that often results in thickened collagen-enriched healed tissue called scar. Cutaneous scars lack many functional structures of the skin such as hair follicles, sweat glands, and papillae. The absence of these structures contributes to a number of the long-term morbidities of wound healing, including loss of function for tissues, increased risk of re-injury, and aesthetic complications. Scar formation is a pervasive factor in our daily lives; however, in the case of serious traumatic injury, scars can create long-lasting complications due to contraction and poor tissue remodeling. Within this report we target the expression of connective tissue growth factor (CTGF), a key mediator of TGFβ pro-fibrotic response in cutaneous wound healing, with controlled local delivery of RNA interference. Through this work we describe both a thorough in vitro analysis of nanolayer coated sutures for the controlled delivery of siRNA and its application to improve scar outcomes in a third-degree burn induced scar model in rats. We demonstrate that the knockdown of CTGF significantly altered the local expression of αSMA, TIMP1, and Col1a1, which are known to play roles in scar formation. The knockdown of CTGF within the healing burn wounds resulted in improved tissue remodeling, reduced scar contraction, and the regeneration of papillary structures within the healing tissue. This work adds support to a number of previous reports that indicate CTGF as a potential therapeutic target for fibrosis. Additionally, we believe that the controlled local delivery of siRNA from ultrathin polymer coatings described within this work is a promising approach in RNA interference that could be applied in developing improved cancer therapies, regenerative medicine, and fundamental scientific research. PMID:27108403

High-resolution analysis of the mechanical behavior of tissue

NASA Astrophysics Data System (ADS)

Hudnut, Alexa W.; Armani, Andrea M.

2017-06-01

The mechanical behavior and properties of biomaterials, such as tissue, have been directly and indirectly connected to numerous malignant physiological states. For example, an increase in the Young's Modulus of tissue can be indicative of cancer. Due to the heterogeneity of biomaterials, it is extremely important to perform these measurements using whole or unprocessed tissue because the tissue matrix contains important information about the intercellular interactions and the structure. Thus, developing high-resolution approaches that can accurately measure the elasticity of unprocessed tissue samples is of great interest. Unfortunately, conventional elastography methods such as atomic force microscopy, compression testing, and ultrasound elastography either require sample processing or have poor resolution. In the present work, we demonstrate the characterization of unprocessed salmon muscle using an optical polarimetric elastography system. We compare the results of compression testing within different samples of salmon skeletal muscle with different numbers of collagen membranes to characterize differences in heterogeneity. Using the intrinsic collagen membranes as markers, we determine the resolution of the system when testing biomaterials. The device reproducibly measures the stiffness of the tissues at variable strains. By analyzing the amount of energy lost by the sample during compression, collagen membranes that are 500 μm in size are detected.

Immunohistochemical study of bone sialoprotein and osteopontin in healthy and diseased root surfaces.

PubMed

Lao, Martin; Marino, Victor; Bartold, P Mark

2006-10-01

Periodontal disease is marked by inflammation and damage to tooth-supporting tissues. In particular, damage occurs to factors present in cementum that are thought to have the ability to influence the regeneration of surrounding tissues. Bone sialoprotein and osteopontin are major non-collagenous proteins in mineralized connective tissues associated with precementoblast chemo-attraction, adhesion to the root surface, and cell differentiation. The purpose of this investigation was to determine whether the expression and distribution of bone sialoprotein and osteopontin on root surfaces affected by periodontitis are altered compared to healthy, non-diseased root surfaces. Thirty healthy and 30 periodontitis-affected teeth were collected. Following fixation and demineralization, specimens were embedded in paraffin, sectioned, and exposed to antibodies against bone sialoprotein and osteopontin. Stained sections were assessed using light microscopy. Bone sialoprotein was not detected in the exposed cementum (absence of overlying periodontal ligament) of diseased teeth. In most areas where the periodontal ligament was intact, bone sialoprotein was detected for healthy and diseased teeth. For teeth reactive for bone sialoprotein, the matrix of the cementum just below the periodontal ligament was moderately stained. A similar immunoreactivity pattern for osteopontin was observed. The absence of bone sialoprotein and osteopontin staining along exposed cementum surfaces may be due to structural and compositional changes in matrix components associated with periodontal disease. This may influence the ability for regeneration and new connective tissue attachment onto previously diseased root surfaces.

What happens to an acellular dermal matrix after implantation in the human body? A histological and electron microscopic study.

PubMed

Boháč, Martin; Danišovič, Ľuboš; Koller, Ján; Dragúňová, Jana; Varga, Ivan

2018-01-22

Acellular matrices are used for various purposes and they have been studied extensively for their potential roles in regenerating tissues or organs. The acellular matrix generates physiological cues that mimic the native tissue microenvironment. Acellular dermal matrix (ADM) is a soft connective tissue graft generated by a decellularization process that preserves the intact extracellular skin matrix. Upon implantation, this structure serves as a scaffold for donor-side cells to facilitate subsequent incorporation and revascularization. In breast reconstruction, ADM is used mainly for lower pole coverage and the shaping of a new breast. It helps control the positioning of the implant in the inframammary fold, and prevent the formation of contractile pseudocapsule around the breast implant. In this study, we provide a comprehensive histological description of ADM used for human breast reconstruction over the course of several months following implementation. Using immunohistochemical methods (a panel of 12 antibodies) coupled with optical and transmission electron microscopy, we confirmed that the original acellular dermal matrix became recolonized by fibroblasts and myofibroblasts, and also by various other free cells of the connective tissue (lymphocytes, macrophages and multinucleated giant cells, granulocytes, mast cells) after implantation into the patient's body. Within the implanted ADM, there was a relatively rapid ingrowth of blood vessels. Lymphatic vessels were only detected in one case 9 months after the implantation of the ADM. These results suggest that lymphangiogenesis is a longer process than angiogenesis.

Oral mucosa tissue response to titanium cover screws.

PubMed

Olmedo, Daniel G; Paparella, María L; Spielberg, Martín; Brandizzi, Daniel; Guglielmotti, María B; Cabrini, Rómulo L

2012-08-01

Titanium is the most widely used metal in dental implantology. The release of particles from metal structures into the biologic milieu may be the result of electrochemical processes (corrosion) and/or mechanical disruption during insertion, abutment connection, or removal of failing implants. The aim of the present study is to evaluate tissue response of human oral mucosa adjacent to titanium cover screws. One hundred fifty-three biopsies of the supra-implant oral mucosa adjacent to the cover screw of submerged dental implants were analyzed. Histologic studies were performed to analyze epithelial and connective tissue as well as the presence of metal particles, which were identified using microchemical analysis. Langerhans cells, macrophages, and T lymphocytes were studied using immunohistochemical techniques. The surface of the cover screws was evaluated by scanning electron microscopy (SEM). Forty-one percent of mucosa biopsies exhibited metal particles in different layers of the section thickness. Particle number and size varied greatly among specimens. Immunohistochemical study confirmed the presence of macrophages and T lymphocytes associated with the metal particles. Microchemical analysis revealed the presence of titanium in the particles. On SEM analysis, the surface of the screws exhibited depressions and irregularities. The biologic effects seen in the mucosa in contact with the cover screws might be associated with the presence of titanium or other elements, such as aluminum or vanadium. The potential long-term biologic effects of particles on soft tissues adjacent to metallic devices should be further investigated because these effects might affect the clinical outcome of the implant.

Clinical and biometrical evaluation of socket preservation using demineralized freeze-dried bone allograft with and without the palatal connective tissue as a biologic membrane.

PubMed

Moghaddas, Hamid; Amjadi, Mohammad Reza; Naghsh, Narges

2012-11-01

Alveolar ridge preservation following tooth extraction has the ability to maintain the ridge dimensions and allow the implant placement in an ideal position fulfilling both functional and aesthetic results. The aim of this study was to evaluate the efficacy of the palatal connective tissue as a biological membrane for socket preservation with demineralized freeze-dried bone allograft (DFDBA). Twelve extraction sites were treated with DFDBA with (case group) and without (control group) using autogenous palatal connective tissue membrane before placement of implants. Alveolar width and height, amount of keratinized tissue, and gingival level were measured at pre-determined points using a surgical stent at two times, the time of socket preservation surgery. In both groups a decrease in all socket dimensions was found. The average decrease in socket width, height, keratinized tissue, and gingival level in case group was 1.16, 0.72, 3.58, and 1.27 mm, and in control group was 2.08, 0.86, 4.52, and 1.58 mm respectively. Statistical analysis showed that decrease in socket width (P = 0.012), keratinized tissue (P ≤ 0.001), and gingival level (P = 0.031) in case group was significantly lower than that of the control group. Results showed no meaningful difference in socket height changes when compared with case and control groups (P = 0.148). Under the limits of this study, connective tissue membrane could preserve socket width, amount of keratinized tissue, and the gingival level more effectively than DFDBA alone.

A Digital Staining Algorithm for Optical Coherence Tomography Images of the Optic Nerve Head

PubMed Central

Mari, Jean-Martial; Aung, Tin; Cheng, Ching-Yu; Strouthidis, Nicholas G.; Girard, Michaël J. A.

2017-01-01

Purpose To digitally stain spectral-domain optical coherence tomography (OCT) images of the optic nerve head (ONH), and highlight either connective or neural tissues. Methods OCT volumes of the ONH were acquired from one eye of 10 healthy subjects. We processed all volumes with adaptive compensation to remove shadows and enhance deep tissue visibility. For each ONH, we identified the four most dissimilar pixel-intensity histograms, each of which was assumed to represent a tissue group. These four histograms formed a vector basis on which we ‘projected' each OCT volume in order to generate four digitally stained volumes P1 to P4. Digital staining was also verified using a digital phantom, and compared with k-means clustering for three and four clusters. Results Digital staining was able to isolate three regions of interest from the proposed phantom. For the ONH, the digitally stained images P1 highlighted mostly connective tissues, as demonstrated through an excellent contrast increase across the anterior lamina cribrosa boundary (3.6 ± 0.6 times). P2 highlighted the nerve fiber layer and the prelamina, P3 the remaining layers of the retina, and P4 the image background. Further, digital staining was able to separate ONH tissue layers that were not well separated by k-means clustering. Conclusion We have described an algorithm that can digitally stain connective and neural tissues in OCT images of the ONH. Translational Relevance Because connective and neural tissues are considerably altered in glaucoma, digital staining of the ONH tissues may be of interest in the clinical management of this pathology. PMID:28174676

Does rat granulation tissue maturation involve gap junction communications?

PubMed

Au, Katherine; Ehrlich, H Paul

2007-07-01

Wound healing, a coordinated process, proceeds by sequential changes in cell differentiation and terminates with the deposition of a new connective tissue matrix, a scar. Initially, there is the migratory fibroblast, followed by the proliferative fibroblast, then the synthetic fibroblast, which transforms into the myofibroblast, and finally the apoptotic fibroblast. Gap junction intercellular communications are proposed to coordinate the stringent control of fibroblast phenotypic changes. Does added oleamide, a natural fatty acid that blocks gap junction intercellular communications, alter the phenotypic progression of wound fibroblasts? Pairs of polyvinyl alcohol sponges attached to Alzet pumps, which constantly pumped either oleamide or vehicle solvent, were implanted subcutaneously into three rats. On day 8, implants were harvested and evaluated histologically and biochemically. The capsule of oleamide-treated sponge contained closely packed fibroblasts with little connective tissue between them. The birefringence intensity of that connective tissue was reduced, indicating a reduced density of collagen fiber bundles. Myofibroblasts, identified immunohistologically by alpha-smooth muscle actin-stained stress fibers, were reduced in oleamide-treated implants. Western blot analysis showing less alpha-smooth muscle actin confirmed the reduced density of myofibroblasts. It appears that oleamide retards the progression of wound repair, where less connective tissue is deposited, the collagen is less organized, and the appearance of myofibroblasts is impaired. These findings support the hypothesis that gap junction intercellular communications between wound fibroblasts in granulation tissue play a role in the progression of repair and the maturation of granulation tissue into scar.

Cerebellar hematoma in a patient with Marfan syndrome.

PubMed

Passalacqua, Marcello; Grasso, Giovanni; Alafaci, Concetta; Collufio, Domenicantonio; Morabito, Antonio; Salpietro, Francesco M; Tomasello, Francesco

2003-08-01

Marfan syndrome is a connective tissue disorder affecting many structures, including the skeleton, lungs, eyes, heart and blood vessels. It is an autosomal dominant inherited disorder due to a mutation of a gene encoding fibrillin-1, which affects connective tissue. Few case reports have associated Marfan syndrome with vascular malformations of the brain and spinal cord. In this regard, association with intracranial aneurysm has been vaguely proposed. We report here a patient with Marfan syndrome who was admitted because of a sudden loss of consciousness. The patient underwent computed tomography (CT) examination, which disclosed a right intracerebellar hematoma. Cerebral angiogram did not demonstrate aneurysm or arteriovenous malformation (AVM), or evidence of any other vascular lesions or neoplasms in the posterior fossa. Conservative treatment was undertaken. The clinical course was uneventful and after 6 weeks the patient was discharged free of symptoms. Although patients with Marfan syndrome are at high risk of vascular abnormalities, a clear association with cerebral aneurysm has not yet been established. Our experience and the contrasting reports available in the medical literature strongly warrant further studies in order to better clarify this controversial association.

Expression of connective tissue growth factor (CTGF/CCN2) in breast cancer cells is associated with increased migration and angiogenesis.

PubMed

Chien, Wenwen; O'Kelly, James; Lu, Daning; Leiter, Amanda; Sohn, Julia; Yin, Dong; Karlan, Beth; Vadgama, Jay; Lyons, Karen M; Koeffler, H Phillip

2011-06-01

Connective tissue growth factor (CTGF/CCN2) belongs to the CCN family of matricellular proteins, comprising Cyr61, CTGF, NovH and WISP1-3. The CCN proteins contain an N-terminal signal peptide followed by four conserved domains sharing sequence similarities with the insulin-like growth factor binding proteins, von Willebrand factor type C repeat, thrombospondin type 1 repeat, and a C-terminal growth factor cysteine knot domain. To investigate the role of CCN2 in breast cancer, we transfected MCF-7 cells with full-length CCN2, and with four mutant constructs in which one of the domains had been deleted. MCF-7 cells stably expressing full-length CCN2 demonstrated reduced cell proliferation, increased migration in Boyden chamber assays and promoted angiogenesis in chorioallantoic membrane assays compared to control cells. Deletion of the C-terminal cysteine knot domain, but not of any other domain-deleted mutants, abolished activities mediated by full-length CCN2. We have dissected the role of CCN2 in breast tumorigenesis on a structural basis.

Connective Tissue Mineralization in Abcc6−/− Mice, a Model for Pseudoxanthoma Elasticum

PubMed Central

Kavukcuoglu, N. Beril; Li, Qiaoli; Pleshko, Nancy; Uitto, Jouni

2012-01-01

Pseudoxanthoma elasticum (PXE) is a heritable multisystem disorder characterized by ectopic mineralization. However, the structure of the mineral deposits, their interactions with the connective tissue matrix, and the details of the progressive maturation of the mineral crystals are currently unknown. In this study, we examined the mineralization processes in Abcc6−/− mice, a model system for PXE, by energy dispersive X-ray, and Fourier transform infrared imaging spectroscopy (FT-IRIS). The results indicated that the principal components of the mineral deposits were calcium and phosphate which co-localized within the histologically demonstrable lesions determined by topographic mapping. The Ca/P ratio increased in samples with progressive mineralization reaching the value comparable to that in endochondral bone. A progressive increase in mineralization was also reflected by increased mineral-to-matrix ratio determined by FT-IRIS. Determination of the mineral phases by FT-IRIS suggested progressive maturation of the mineral deposits from amorphous calcium phosphate to hydroxyapatite. These results provide critical information of the mechanisms of mineralization in PXE, with potential pharmacologic implications. PMID:22421595

Copper and the Prion Protein: Methods, Structures, Function, and Disease

NASA Astrophysics Data System (ADS)

Millhauser, Glenn L.

2007-05-01

The transmissible spongiform encephalopathies (TSEs) arise from conversion of the membrane-bound prion protein from PrPC to PrPSc. Examples of the TSEs include mad cow disease, chronic wasting disease in deer and elk, scrapie in goats and sheep, and kuru and Creutzfeldt-Jakob disease in humans. Although the precise function of PrPC in healthy tissues is not known, recent research demonstrates that it binds Cu(II) in an unusual and highly conserved region of the protein termed the octarepeat domain. This review describes recent connections between copper and PrPC, with an emphasis on the electron paramagnetic resonance elucidation of the specific copper-binding sites, insights into PrPC function, and emerging connections between copper and prion disease.

Xenogeneic Collagen Matrix Versus Connective Tissue Graft: Case Series of Various Gingival Recession Treatments.

PubMed

Chevalier, Grégoire; Cherkaoui, Selma; Kruk, Hanna; Bensaïd, Xavier; Danan, Marc

A xenogeneic collagen matrix recently has been suggested as an alternative to connective tissue graft for the treatment of gingival recession. The matrix avoids the second surgical site, and as a consequence could decrease surgical morbidity. This new matrix was used in various clinical situations and compared to connective tissue graft (CTG) in a split-mouth design case series. A total of 17 recessions were treated with a coronally advanced flap, 9 with CTG, and 8 with the matrix. Mean recession reduction was 2.00 mm with the CTG and 2.00 mm with the matrix. No significant statistical differences between the techniques were observed in this case report.

Xenogeneic Collagen Matrix Versus Connective Tissue Graft: Case Series of Various Gingival Recession Treatments.

PubMed

Chevalier, Grégoire; Cherkaoui, Selma; Kruk, Hanna; Bensaïd, Xavier; Danan, Marc

2016-08-24

A xenogeneic collagen matrix recently has been suggested as an alternative to connective tissue graft for the treatment of gingival recession. The matrix avoids the second surgical site, and as a consequence could decrease surgical morbidity. This new matrix was used in various clinical situations and compared to connective tissue graft (CTG) in a split-mouth design case series. A total of 17 recessions were treated with a coronally advanced flap, 9 with CTG, and 8 with the matrix. Mean recession reduction was 2.00 mm with the CTG and 2.00 mm with the matrix. No significant statistical differences between the techniques were observed in this case report.

Systemic sclerosis-scleroderma.

PubMed

Haustein, U-F

2002-06-01

Systemic sclerosis is a clinically heterogeneous, systemic disorder which affects the connective tissue of the skin, internal organs and the walls of blood vessels. It is characterized by alterations of the microvasculature, disturbances of the immune system and by massive deposition of collagen and other matrix substances in the connective tissue. This review discusses epidemiology and survival, clinical features including subsets and internal organ involvement, pathophysiology and genetics, microvasculature, immunobiology, fibroblasts and connective tissue metabolism and environmental factors. Early diagnosis and individually tailored therapy help to manage this disorder, which is treatable, but not curable. Therapy involves immunomodulation as well as the targeting of blood vessel mechanics and fibrosis. Physical therapy and psychotherapy are also important adjunctive therapies in this multifactorial disease.

Fibrosis in connective tissue disease: the role of the myofibroblast and fibroblast-epithelial cell interactions

PubMed Central

Krieg, Thomas; Abraham, David; Lafyatis, Robert

2007-01-01

Fibrosis, characterized by excessive extracellular matrix accumulation, is a common feature of many connective tissue diseases, notably scleroderma (systemic sclerosis). Experimental studies suggest that a complex network of intercellular interactions involving endothelial cells, epithelial cells, fibroblasts and immune cells, using an array of molecular mediators, drives the pathogenic events that lead to fibrosis. Transforming growth factor-β and endothelin-1, which are part of a cytokine hierarchy with connective tissue growth factor, are key mediators of fibrogenesis and are primarily responsible for the differentiation of fibroblasts toward a myofibroblast phenotype. The tight skin mouse (Tsk-1) model of cutaneous fibrosis suggests that numerous other genes may also be important. PMID:17767742

Mineralization/Anti-Mineralization Networks in the Skin and Vascular Connective Tissues

PubMed Central

Li, Qiaoli; Uitto, Jouni

2014-01-01

Ectopic mineralization has been linked to several common clinical conditions with considerable morbidity and mortality. The mineralization processes, both metastatic and dystrophic, affect the skin and vascular connective tissues. There are several contributing metabolic and environmental factors that make uncovering of the precise pathomechanisms of these acquired disorders exceedingly difficult. Several relatively rare heritable disorders share phenotypic manifestations similar to those in common conditions, and, consequently, they serve as genetically controlled model systems to study the details of the mineralization process in peripheral tissues. This overview will highlight diseases with mineral deposition in the skin and vascular connective tissues, as exemplified by familial tumoral calcinosis, pseudoxanthoma elasticum, generalized arterial calcification of infancy, and arterial calcification due to CD73 deficiency. These diseases, and their corresponding mouse models, provide insight into the pathomechanisms of soft tissue mineralization and point to the existence of intricate mineralization/anti-mineralization networks in these tissues. This information is critical for understanding the pathomechanistic details of different mineralization disorders, and it has provided the perspective to develop pharmacological approaches to counteract the consequences of ectopic mineralization. PMID:23665350

Structural alterations in rat myocardium induced by chronic l-arginine and l-NAME supplementation.

PubMed

Hmaid, Amal Abdussalam Ali A; Markelic, Milica; Otasevic, Vesna; Masovic, Sava; Jankovic, Aleksandra; Korac, Bato; Korac, Aleksandra

2018-03-01

Structural changes affecting cardiomyocyte function may contribute to the pathophysiological remodeling underlying cardiac function impairment. Recent reports have shown that endogenous nitric oxide (NO) plays an important role in this process. In order to examine the role of NO in cardiomyocyte remodeling, male rats were acclimated to room temperature (22 ± 1 °C) or cold (4 ± 1 °C) and treated with 2.25% l-arginine·HCl or 0.01% l-NAME (N ω -nitro-l-arginine methyl ester)·HCl for 45 days. Untreated groups served as controls. Right heart ventricles were routinely prepared for light microscopic examination. Stereological estimations of volume densities of cardiomyocytes, surrounding blood vessels and connective tissue, as well as the morphometric measurements of cardiomyocyte diameters were performed. Tissue sections were also analyzed for structural alterations. We observed that both l-arginine and l-NAME supplementation induced cardiomyocyte hypertrophy, regardless of ambient temperature. However, cardiomyocyte hypertrophy was associated with fibrosis and extra collagen deposition only in the l-NAME treated group. Taken together, our results suggest that NO has a modulatory role in right heart ventricle remodeling by coordinating hypertrophy of cardiomyocytes and fibrous tissue preventing cardiac fibrosis.

From single fiber to macro-level mechanics: A structural finite-element model for elastomeric fibrous biomaterials

PubMed Central

D'Amore, Antonio; Amoroso, Nicholas; Gottardi, Riccardo; Hobson, Christopher; Carruthers, Christopher; Watkins, Simon; Wagner, William R.; Sacks, Michael S.

2014-01-01

In the present work, we demonstrate that the mesoscopic in-plane mechanical behavior of membrane elastomeric scaffolds can be simulated by replication of actual quantified fibrous geometries. Elastomeric electrospun polyurethane (ES-PEUU) scaffolds, with and without particulate inclusions, were utilized. Simulations were developed from experimentally-derived fiber network geometries, based on a range of scaffold isotropic and anisotropic behaviors. These were chosen to evaluate the effects on macro-mechanics based on measurable geometric parameters such as fiber intersections, connectivity, orientation, and diameter. Simulations were conducted with only the fiber material model parameters adjusted to match the macro-level mechanical test data. Fiber model validation was performed at the microscopic level by individual fiber mechanical tests using AFM. Results demonstrated very good agreement to the experimental data, and revealed the formation of extended preferential fiber orientations spanning the entire model space. We speculate that these emergent structures may be responsible for the tissue-like macroscale behaviors observed in electrospun scaffolds. To conclude, the modeling approach has implications for (1) gaining insight on the intricate relationship between fabrication variables, structure, and mechanics to manufacture more functional devices/materials, (2) elucidating the effects of cell or particulate inclusions on global construct mechanics, and (3) fabricating better performing tissue surrogates that could recapitulate native tissue mechanics. PMID:25128869

In vitro fabrication of functional three-dimensional tissues with perfusable blood vessels

PubMed Central

Sekine, Hidekazu; Shimizu, Tatsuya; Sakaguchi, Katsuhisa; Dobashi, Izumi; Wada, Masanori; Yamato, Masayuki; Kobayashi, Eiji; Umezu, Mitsuo; Okano, Teruo

2013-01-01

In vitro fabrication of functional vascularized three-dimensional tissues has been a long-standing objective in the field of tissue engineering. Here we report a technique to engineer cardiac tissues with perfusable blood vessels in vitro. Using resected tissue with a connectable artery and vein as a vascular bed, we overlay triple-layer cardiac cell sheets produced from coculture with endothelial cells, and support the tissue construct with media perfused in a bioreactor. We show that endothelial cells connect to capillaries in the vascular bed and form tubular lumens, creating in vitro perfusable blood vessels in the cardiac cell sheets. Thicker engineered tissues can be produced in vitro by overlaying additional triple-layer cell sheets. The vascularized cardiac tissues beat and can be transplanted with blood vessel anastomoses. This technique may create new opportunities for in vitro tissue engineering and has potential therapeutic applications. PMID:23360990

Mesenchymal stem cells in tumor development

PubMed Central

Cuiffo, Benjamin G.; Karnoub, Antoine E.

2012-01-01

Mesenchymal stem cells (MSCs) are multipotent progenitor cells that participate in the structural and functional maintenance of connective tissues under normal homeostasis. They also act as trophic mediators during tissue repair, generating bioactive molecules that help in tissue regeneration following injury. MSCs serve comparable roles in cases of malignancy and are becoming increasingly appreciated as critical components of the tumor microenvironment. MSCs home to developing tumors with great affinity, where they exacerbate cancer cell proliferation, motility, invasion and metastasis, foster angiogenesis, promote tumor desmoplasia and suppress anti-tumor immune responses. These multifaceted roles emerge as a product of reciprocal interactions occurring between MSCs and cancer cells and serve to alter the tumor milieu, setting into motion a dynamic co-evolution of both tumor and stromal tissues that favors tumor progression. Here, we summarize our current knowledge about the involvement of MSCs in cancer pathogenesis and review accumulating evidence that have placed them at the center of the pro-malignant tumor stroma. PMID:22863739

Innovative application of optical techniques to comprehensive study of the etiology of osteoarthritis

NASA Astrophysics Data System (ADS)

Ugryumova, Nadya; Matcher, Stephen J.

2006-08-01

Osteoarthritis is a painful condition, causing restricted mobility in the articular joints. In this paper we present a review of different optical techniques that might be used to clarify the etiology of degeneration of connective joint tissues, such as bone and articular cartilage. Significant correlation (R2 = 0.8) between bone mineral density and scattering coefficient of cortical bone tissue are found by using Integrating Sphere Technique. Optical Coherence Tomography and Polarization-Sensitive Optical Coherence Tomography images of cartilage tissue are presented. They were performed as series of angle-dependant measurements for different location along the surface. Method for spatial mapping the birefringence of equine articular cartilage is proposed. Variations in band spacing of birefringence obtained from visually healthy and abnormal cartilage samples are compared. Visible osteoarthritic lesions are characterized by a loss of the regular birefringence bands shown by normal cartilage. We discuss the hypothesis that some of these variations may be due to changes in intrinsic structure of tissue.

Live Imaging of Axolotl Digit Regeneration Reveals Spatiotemporal Choreography of Diverse Connective Tissue Progenitor Pools.

PubMed

Currie, Joshua D; Kawaguchi, Akane; Traspas, Ricardo Moreno; Schuez, Maritta; Chara, Osvaldo; Tanaka, Elly M

2016-11-21

Connective tissues-skeleton, dermis, pericytes, fascia-are a key cell source for regenerating the patterned skeleton during axolotl appendage regeneration. This complexity has made it difficult to identify the cells that regenerate skeletal tissue. Inability to identify these cells has impeded a mechanistic understanding of blastema formation. By tracing cells during digit tip regeneration using brainbow transgenic axolotls, we show that cells from each connective tissue compartment have distinct spatial and temporal profiles of proliferation, migration, and differentiation. Chondrocytes proliferate but do not migrate into the regenerate. In contrast, pericytes proliferate, then migrate into the blastema and give rise solely to pericytes. Periskeletal cells and fibroblasts contribute the bulk of digit blastema cells and acquire diverse fates according to successive waves of migration that choreograph their proximal-distal and tissue contributions. We further show that platelet-derived growth factor signaling is a potent inducer of fibroblast migration, which is required to form the blastema. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Recombinant Amelogenin Protein Induces Apical Closure and Pulp Regeneration in Open-apex, Non-vital Permanent Canine Teeth

PubMed Central

Mounir, Maha M.F.; Matar, Moustafa A.; Lei, Yaping; Snead, Malcolm L.

2015-01-01

Introduction Recombinant DNA produced amelogenin protein was compared to calcium hydroxide in a study of immature apex closure conducted in 24 young mongrel dogs. Methods Root canals of maxillary and mandibular right premolars (n = 240) were instrumented and left open for 14 days. Canals were cleansed, irrigated and split equally for treatment with recombinant mouse amelogenin (n = 120) or calcium hydroxide (n = 120). Results After 1, 3, and 6 months, the animals were sacrificed and the treated teeth recovered for histological assessment and immunodetection of protein markers associated with odontogenic cells. After 1 month, amelogenin-treated canals revealed calcified tissue formed at the apical foramen and a pulp chamber containing soft connective tissue and hard tissue; amelogenin-treated canals assessed after 3 and 6 month intervals further included apical tissue functionally attached to bone by a periodontal ligament. In contrast, calcified apical tissue was poorly formed in the calcium hydroxide group and soft connective tissue within the pulp chamber was not observed. Conclusions The findings from this experimental strategy suggest recombinant amelogenin protein can signal cells to enhance apex formation in non-vital immature teeth and promote soft connective tissue regeneration. PMID:26709200

[Anatomy and pathogenesis of diverticular disease].

PubMed

Wedel, T; Böttner, M

2014-04-01

Although diverticular disease is one of the most frequent gastrointestinal disorders the pathogenesis is not yet sufficiently clarified. The aim is to define the anatomy and pathogenesis of diverticular disease considering the risk factors and description of structural and functional alterations of the bowel wall. This article gives an appraisal of the literature, presentation and evaluation of classical etiological factors, analysis and discussion of novel pathogenetic concepts. Colonic diverticulosis is defined as an acquired out-pouching of multiple and initially asymptomatic pseudodiverticula through muscular gaps in the colon wall. Diverticular disease is characterized by diverticular bleeding and/or inflammatory processes (diverticulitis) with corresponding complications (e.g. abscess formation, fistula, covered and open perforation, peritonitis and stenosis). Risk factors for diverticular disease include increasing age, genetic predisposition, congenital connective tissue diseases, low fiber diet, high meat consumption and pronounced overweight. Alterations of connective tissue cause a weakening of preformed exit sites of diverticula and rigidity of the bowel wall with reduced flexibility. It is assumed that intestinal innervation disorders and structural alterations of the musculature induce abnormal contractile patterns with increased intraluminal pressure, thereby promoting the development of diverticula. Moreover, an increased release of pain-mediating neurotransmitters is considered to be responsible for persistent pain in chronic diverticular disease. According to the present data the pathogenesis of diverticular disease cannot be attributed to a single factor but should be considered as a multifactorial event.

Mandibular phosphaturic mesenchymal tumor-mixed connective tissue variant in a young girl.

PubMed

Luo, Lisa; Low, Nelson; Vandervord, John

2013-11-01

Phosphaturic mesenchymal tumor-mixed connective tissue variant (PMTMCT) is an extremely rare tumor associated with tumor-induced osteomalacia. The majority occur in middle age and arise from the extremities. This report describes a young girl with PMTMCT arising in the mandible and with no evidence of paraneoplastic syndrome.

Differences in manifestations of Marfan syndrome, Ehlers-Danlos syndrome, and Loeys-Dietz syndrome.

PubMed

Meester, Josephina A N; Verstraeten, Aline; Schepers, Dorien; Alaerts, Maaike; Van Laer, Lut; Loeys, Bart L

2017-11-01

Many different heritable connective tissue disorders (HCTD) have been described over the past decades. These syndromes often affect the connective tissue of various organ systems, including heart, blood vessels, skin, joints, bone, eyes, and lungs. The discovery of these HCTD was followed by the identification of mutations in a wide range of genes encoding structural proteins, modifying enzymes, or components of the TGFβ-signaling pathway. Three typical examples of HCTD are Marfan syndrome (MFS), Ehlers-Danlos syndrome (EDS), and Loeys-Dietz syndrome (LDS). These syndromes show some degree of phenotypical overlap of cardiovascular, skeletal, and cutaneous features. MFS is typically characterized by cardiovascular, ocular, and skeletal manifestations and is caused by heterozygous mutations in FBN1 , coding for the extracellular matrix (ECM) protein fibrillin-1. The most common cardiovascular phenotype involves aortic aneurysm and dissection at the sinuses of Valsalva. LDS is caused by mutations in TGBR1/2 , SMAD2/3 , or TGFB2/3 , all coding for components of the TGFβ-signaling pathway. LDS can be distinguished from MFS by the unique presence of hypertelorism, bifid uvula or cleft palate, and widespread aortic and arterial aneurysm and tortuosity. Compared to MFS, LDS cardiovascular manifestations tend to be more severe. In contrast, no association is reported between LDS and the presence of ectopia lentis, a key distinguishing feature of MFS. Overlapping features between MFS and LDS include scoliosis, pes planus, anterior chest deformity, spontaneous pneumothorax, and dural ectasia. EDS refers to a group of clinically and genetically heterogeneous connective tissue disorders and all subtypes are characterized by variable abnormalities of skin, ligaments and joints, blood vessels, and internal organs. Typical presenting features include joint hypermobility, skin hyperextensibility, and tissue fragility. Up to one quarter of the EDS patients show aortic aneurysmal disease. The latest EDS nosology distinguishes 13 subtypes. Many phenotypic features show overlap between the different subtypes, which makes the clinical diagnosis rather difficult and highlights the importance of molecular diagnostic confirmation.

Differences in manifestations of Marfan syndrome, Ehlers-Danlos syndrome, and Loeys-Dietz syndrome

PubMed Central

Meester, Josephina A. N.; Verstraeten, Aline; Schepers, Dorien; Alaerts, Maaike; Van Laer, Lut

2017-01-01

Many different heritable connective tissue disorders (HCTD) have been described over the past decades. These syndromes often affect the connective tissue of various organ systems, including heart, blood vessels, skin, joints, bone, eyes, and lungs. The discovery of these HCTD was followed by the identification of mutations in a wide range of genes encoding structural proteins, modifying enzymes, or components of the TGFβ-signaling pathway. Three typical examples of HCTD are Marfan syndrome (MFS), Ehlers-Danlos syndrome (EDS), and Loeys-Dietz syndrome (LDS). These syndromes show some degree of phenotypical overlap of cardiovascular, skeletal, and cutaneous features. MFS is typically characterized by cardiovascular, ocular, and skeletal manifestations and is caused by heterozygous mutations in FBN1, coding for the extracellular matrix (ECM) protein fibrillin-1. The most common cardiovascular phenotype involves aortic aneurysm and dissection at the sinuses of Valsalva. LDS is caused by mutations in TGBR1/2, SMAD2/3, or TGFB2/3, all coding for components of the TGFβ-signaling pathway. LDS can be distinguished from MFS by the unique presence of hypertelorism, bifid uvula or cleft palate, and widespread aortic and arterial aneurysm and tortuosity. Compared to MFS, LDS cardiovascular manifestations tend to be more severe. In contrast, no association is reported between LDS and the presence of ectopia lentis, a key distinguishing feature of MFS. Overlapping features between MFS and LDS include scoliosis, pes planus, anterior chest deformity, spontaneous pneumothorax, and dural ectasia. EDS refers to a group of clinically and genetically heterogeneous connective tissue disorders and all subtypes are characterized by variable abnormalities of skin, ligaments and joints, blood vessels, and internal organs. Typical presenting features include joint hypermobility, skin hyperextensibility, and tissue fragility. Up to one quarter of the EDS patients show aortic aneurysmal disease. The latest EDS nosology distinguishes 13 subtypes. Many phenotypic features show overlap between the different subtypes, which makes the clinical diagnosis rather difficult and highlights the importance of molecular diagnostic confirmation. PMID:29270370

Macroscopic and histological investigation of guanaco footpads (Lama guanicoe, Müller 1776).

PubMed

König, Horst Erich; Skewes, Oscar; Helmreich, Magda; Böck, Peter

2015-03-01

The surface of guanaco footpads is characterized by hairless skin with up to 4-mm-thick stratum corneum that protects from abrasion. The horny layer is pliable and elastic, and ensures firm contact with irregular ground. It is padded with a particular structure of the subcutaneous layer, the digital cushion. The flat cushions of each of the two digits are of elongated ovate shape, each about 45-mm long, up to 20-mm wide, and 8-mm thick. The cushions are lined by a 1-2-mm-thick capsule that resembles a tunica albuginea. The capsule consists of coarse collagen fibers, with elastic fibers absent. The cushion capsule and dermis approach each other, and fuse along a line that runs parallel to the longitudinal axes of cushion and digit. Loose connective tissue rich in elastic fibers and acidic glycosaminoglycans separates dermis and cushion capsule lateral to the narrow interconnecting zone. The cushion capsule encloses cloudy yellowish, gelatinous material. Microscopy shows bundles of elastic fibers in abundant mucinous matrix. Tightly gathered elastic bundles adjoin the inner surface of the capsule. Rough cords of elastic fibers branch out from there and traverse to the opposite side. The cushion is pressed flat, and elastic fibers are stretched when bearing weight. With relief of load, elastic fibers contract and reset the cushion's shape. Contractile cells are absent. A resistant capsule and easily malleable mucinous contents establish the functioning as a gel pad. Mucinous connective tissue between elastic fiber bundles contains abundant basophilic matrix. Hyaluronan, chondroitin sulfate, and dermatan sulfate are main matrix constituents. Spindle-shaped or stellate fibroblasts contain vimentin, S100 protein, and neuron specific enolase. Moprhology, staining characteristics and synthesis activities of these cells meet the criteria to be classified as myxoid cells. The connective tissue in guanaco digital cushions represents myxoid tissue. © 2014 Wiley Periodicals, Inc.

An in vivo MRI Template Set for Morphometry, Tissue Segmentation, and fMRI Localization in Rats

PubMed Central

Valdés-Hernández, Pedro Antonio; Sumiyoshi, Akira; Nonaka, Hiroi; Haga, Risa; Aubert-Vásquez, Eduardo; Ogawa, Takeshi; Iturria-Medina, Yasser; Riera, Jorge J.; Kawashima, Ryuta

2011-01-01

Over the last decade, several papers have focused on the construction of highly detailed mouse high field magnetic resonance image (MRI) templates via non-linear registration to unbiased reference spaces, allowing for a variety of neuroimaging applications such as robust morphometric analyses. However, work in rats has only provided medium field MRI averages based on linear registration to biased spaces with the sole purpose of approximate functional MRI (fMRI) localization. This precludes any morphometric analysis in spite of the need of exploring in detail the neuroanatomical substrates of diseases in a recent advent of rat models. In this paper we present a new in vivo rat T2 MRI template set, comprising average images of both intensity and shape, obtained via non-linear registration. Also, unlike previous rat template sets, we include white and gray matter probabilistic segmentations, expanding its use to those applications demanding prior-based tissue segmentation, e.g., statistical parametric mapping (SPM) voxel-based morphometry. We also provide a preliminary digitalization of latest Paxinos and Watson atlas for anatomical and functional interpretations within the cerebral cortex. We confirmed that, like with previous templates, forepaw and hindpaw fMRI activations can be correctly localized in the expected atlas structure. To exemplify the use of our new MRI template set, were reported the volumes of brain tissues and cortical structures and probed their relationships with ontogenetic development. Other in vivo applications in the near future can be tensor-, deformation-, or voxel-based morphometry, morphological connectivity, and diffusion tensor-based anatomical connectivity. Our template set, freely available through the SPM extension website, could be an important tool for future longitudinal and/or functional extensive preclinical studies. PMID:22275894

Systemic connective tissue features in women with fibromuscular dysplasia.

PubMed

O'Connor, Sarah; Kim, Esther Sh; Brinza, Ellen; Moran, Rocio; Fendrikova-Mahlay, Natalia; Wolski, Kathy; Gornik, Heather L

2015-10-01

Fibromuscular dysplasia (FMD) is a non-atherosclerotic disease associated with hypertension, headache, dissection, stroke, and aneurysm. The etiology is unknown but hypothesized to involve genetic and environmental components. Previous studies suggest a possible overlap of FMD with other connective tissue diseases that present with dissections and aneurysms. The aim of this study was to investigate the prevalence of connective tissue physical features in FMD. A total of 142 FMD patients were consecutively enrolled at a single referral center (97.9% female, 92.1% of whom had multifocal FMD). Data are reported for 139 female patients. Moderately severe myopia (29.1%), high palate (33.1%), dental crowding (29.7%), and early-onset arthritis (15.6%) were prevalent features. Classic connective features such as hypertelorism, cleft palate, and hypermobility were uncommon. The frequency of systemic connective tissue features was compared between FMD patients with a high vascular risk profile (having had ⩾1 dissection and/or ⩾2 aneurysms) and those with a standard vascular risk profile. A history of spontaneous pneumothorax (5.9% high risk vs 0% standard risk) and atrophic scarring (17.6% high risk vs 6.8% standard risk) were significantly more prevalent in the high risk group, p<0.05. High palate was observed in 43.1% of the high risk group versus 27.3% in the standard risk group, p=0.055. In conclusion, in a cohort of women with FMD, there was a prevalence of moderately severe myopia, high palate, dental crowding, and early-onset osteoarthritis. However, a characteristic phenotype was not discovered. Several connective tissue features such as high palate and pneumothorax were more prominent among FMD patients with a high vascular risk profile. © The Author(s) 2015.

Systemic Connective Tissue Features in Women with Fibromuscular Dysplasia

PubMed Central

O’Connor, Sarah; Kim, Esther S. H.; Brinza, Ellen; Moran, Rocio; Fendrikova-Mahlay, Natalia; Wolski, Kathy; Gornik, Heather L.

2016-01-01

Background Fibromuscular Dysplasia (FMD) is an non-atherosclerotic disease associated with hypertension, headache, dissection, stroke, and aneurysm. The etiology is unknown but hypothesized to involve genetic and environmental components. Previous studies suggest a possible overlap of FMD with other connective tissue diseases that present with dissections and aneurysms. The aim of this study was to investigate the prevalence of connective tissue physical features in FMD. Methods and Results 142 FMD patients were consecutively enrolled at a single referral center (97.9% female, 92.3% had multifocal FMD). Data are reported for 139 female patients. Moderately severe myopia (29.1%), high palate (33.1%), dental crowding (29.7%), and early onset arthritis (15.6%) were prevalent features. Classic connective features such as hypertelorism, cleft palate, and hypermobility were uncommon. Frequency of systemic connective tissue features was compared between FMD patients with a high vascular risk profile (having had ≥1 dissection and/or ≥2 aneurysms) and those with a standard vascular risk profile. History of spontaneous pneumothorax (5.9% high risk vs. 0% standard risk) and atrophic scarring (17.3% high risk vs. 6.8% standard risk) were significantly more prevalent in the high risk group, p<0.05. High palate was observed in 43.1% of the high risk group vs. 27.3% in the standard risk group, p=0.055. Conclusions In a cohort of women with FMD, there was a prevalence of moderately severe myopia, high palate, dental crowding, and early onset osteoarthritis. However, a characteristic phenotype was not discovered. Several connective tissue features such as high palate and pneumothorax were more prominent among FMD patients with a high vascular risk profile. PMID:26156071

Acellular dermal matrix in soft tissue reconstruction prior to bone grafting. A case report.

PubMed

Ruiz-Magaz, Vanessa; Hernández-Alfaro, Federico; Díaz-Carandell, Artur; Biosca-Gómez-de-Tejada, María-José

2010-01-01

When hard tissue augmentation is scheduled as a part of an oral rehabilitation, prior to the treatment, it is important to assess if the quality of the underlying gingiva at the recipient site can support the bone grafting procedure. The most frequent complication during autologous onlay grafts are wound dehiscences in the recipient site, so the integrity of soft tissues is a basic aspect of successful reconstructive and plastic surgical procedure. Connective tissue grafts can improve the quality and quantity of soft tissue in oral sites where a hard tissue reconstruction is going to take place. However, particularly when large grafts are harvested, the autogenous donor site can present significant postoperative morbidity, such as necrosis of the palate fibromucosa and bone exposition, pain and bleeding. Another important limitation with the use of autogenous grafts is the limited supply of donor connective tissue. If a large site needs to be grafted, more than one surgical procedure may be required. An Acellular Dermal Matrix (ADM) graft has become increasingly popular as a substitute for donor connective tissue, eliminating the disadvantages described for the autogenous donor graft. The amount of tissue harvested is unlimited, so it gives an option for treating patients that have inadequate harvestable tissue or that present a large defect to be treated. The outcome of using ADM as a matrix for soft tissue reconstruction 12 weeks before bone grafting can reduce the risk of exposure and failure of the bone graft.

Aging-associated modifications of collagen affect its degradation by matrix metalloproteinases.

PubMed

Panwar, Preety; Butler, Georgina S; Jamroz, Andrew; Azizi, Pouya; Overall, Christopher M; Brömme, Dieter

2018-01-01

The natural aging process and various pathologies correlate with alterations in the composition and the structural and mechanical integrity of the connective tissue. Collagens represent the most abundant matrix proteins and provide for the overall stiffness and resilience of tissues. The structural changes of collagens and their susceptibility to degradation are associated with skin wrinkling, bone and cartilage deterioration, as well as cardiovascular and respiratory malfunctions. Here, matrix metalloproteinases (MMPs) are major contributors to tissue remodeling and collagen degradation. During aging, collagens are modified by mineralization, accumulation of advanced glycation end-products (AGEs), and the depletion of glycosaminoglycans (GAGs), which affect fiber stability and their susceptibility to MMP-mediated degradation. We found a reduced collagenolysis in mineralized and AGE-modified collagen fibers when compared to native fibrillar collagen. GAGs had no effect on MMP-mediated degradation of collagen. In general, MMP digestion led to a reduction in the mechanical strength of native and modified collagen fibers. Successive fiber degradation with MMPs and the cysteine-dependent collagenase, cathepsin K (CatK), resulted in their complete degradation. In contrast, MMP-generated fragments were not or only poorly cleaved by non-collagenolytic cathepsins such as cathepsin V (CatV). In conclusion, our data indicate that aging and disease-associated collagen modifications reduce tissue remodeling by MMPs and decrease the structural and mechanic integrity of collagen fibers, which both may exacerbate extracellular matrix pathology. Copyright © 2017 Elsevier B.V. All rights reserved.

Molecular level detection and localization of mechanical damage in collagen enabled by collagen hybridizing peptides.

PubMed

Zitnay, Jared L; Li, Yang; Qin, Zhao; San, Boi Hoa; Depalle, Baptiste; Reese, Shawn P; Buehler, Markus J; Yu, S Michael; Weiss, Jeffrey A

2017-03-22

Mechanical injury to connective tissue causes changes in collagen structure and material behaviour, but the role and mechanisms of molecular damage have not been established. In the case of mechanical subfailure damage, no apparent macroscale damage can be detected, yet this damage initiates and potentiates in pathological processes. Here, we utilize collagen hybridizing peptide (CHP), which binds unfolded collagen by triple helix formation, to detect molecular level subfailure damage to collagen in mechanically stretched rat tail tendon fascicle. Our results directly reveal that collagen triple helix unfolding occurs during tensile loading of collagenous tissues and thus is an important damage mechanism. Steered molecular dynamics simulations suggest that a likely mechanism for triple helix unfolding is intermolecular shearing of collagen α-chains. Our results elucidate a probable molecular failure mechanism associated with subfailure injuries, and demonstrate the potential of CHP targeting for diagnosis, treatment and monitoring of tissue disease and injury.

Electromechanical integration of cardiomyocytes derived from human embryonic stem cells.

PubMed

Kehat, Izhak; Khimovich, Leonid; Caspi, Oren; Gepstein, Amira; Shofti, Rona; Arbel, Gil; Huber, Irit; Satin, Jonathan; Itskovitz-Eldor, Joseph; Gepstein, Lior

2004-10-01

Cell therapy is emerging as a promising strategy for myocardial repair. This approach is hampered, however, by the lack of sources for human cardiac tissue and by the absence of direct evidence for functional integration of donor cells into host tissues. Here we investigate whether cells derived from human embryonic stem (hES) cells can restore myocardial electromechanical properties. Cardiomyocyte cell grafts were generated from hES cells in vitro using the embryoid body differentiating system. This tissue formed structural and electromechanical connections with cultured rat cardiomyocytes. In vivo integration was shown in a large-animal model of slow heart rate. The transplanted hES cell-derived cardiomyocytes paced the hearts of swine with complete atrioventricular block, as assessed by detailed three-dimensional electrophysiological mapping and histopathological examination. These results demonstrate the potential of hES-cell cardiomyocytes to act as a rate-responsive biological pacemaker and for future myocardial regeneration strategies.

THE COMPARATIVE RESISTANCE OF BACTERIA AND HUMAN TISSUE CELLS TO CERTAIN COMMON ANTISEPTICS

PubMed Central

Lambert, Robert A.

1916-01-01

The comparative resistance of bacteria and human tissue cells to antiseptics and other chemicals may be easily tested by tissue cultures under conditions which approximate those found in the living body. A comparative study shows that while human cells (connective tissue and wandering cells) are highly resistant to many antiseptics, they are in general more easily killed than bacteria (Staphylococcus aureus). Of the antiseptics tested, which include mercuric chloride, iodine, potassium mercuric iodide, phenol, tricresol, hydrogen peroxide, hypochlorites (Dakin's solution), argyrol, and alcohol, the one which approaches most closely the ideal disinfectant is iodine, which kills bacteria in strengths that do not seriously injure connective tissue cells or wandering cells. PMID:19868066

The morphological difference between glaucoma and other optic neuropathies

PubMed Central

Burgoyne, Claude

2016-01-01

The clinical phenomenon of cupping has two principal pathophysiologic components in all optic neuropathies: prelaminar thinning and laminar deformation. We define prelaminar thinning to be the portion of cup enlargement that results from thinning of the prelaminar tissues due to physical compression and/or loss of Retinal Ganglion Cell axons. We define laminar deformation or laminar cupping to be the portion of cup enlargement that results from permanent, intraocular pressure-(IOP) induced deformation of the lamina cribrosa and peripapillary scleral connective tissues following damage and/or remodeling. We propose that the defining phenomenon of glaucomatous cupping is deformation and/or remodeling of the neural and connective tissues of the optic nerve head (ONH), which is governed by the distribution of IOP-related connective tissue stress and strain, regardless of the mechanism of insult or the level of IOP at which that deformation and/or remodeling occurs. Said in another way, “glaucomatous cupping” is the term clinicians use to describe the clinical appearance and behavior the ONH assumes as its neural and connective tissues deform, remodel or mechanically fail: 1) in a pattern and 2) by the several pathophysiologic processes governed by IOP-related connective tissue stress and strain. ONH Biomechanics explains why a given optic nerve head will demonstrate a certain form of “cupping” and at what level of IOP that might happen. Animal models are allowing us to tease apart the important components of cupping in IOP-related and non-IOP-related forms of optic neuropathy. A paradigm change in spectral domain optical coherence tomography ONH, retinal nerve fiber layer and Macular imaging should improve our ability to phenotype all forms of damage to the visual system including glaucoma. PMID:26274837

Comparison of Demineralized Dentin and Demineralized Freeze Dried Bone as Carriers for Enamel Matrix Proteins in a Rat Critical Size Defect

DTIC Science & Technology

2005-05-01

matrix derivative or connective tissue . Part 1: comparison of clinical parameters. J Periodontol 2003;74:1110-1125. Minabe M.: A critical review of the... connective tissue , both bone and PDL can serve as sources of progenitor cells for regeneration. Surgical techniques started to evolve with the knowledge...regeneration was Prichard in 1977. This technique involved removal of overlying gingival tissue leaving interdental bone denuded (Prichard 1977). In 1983

Muscular innervation of the proximal duodenum of the guinea pig.

PubMed

Iino, S

2000-10-01

We investigated the muscular structure and innervation of the gastroduodenal junction in the guinea pig. In the gastroduodenal junction, the innermost layer of the circular muscle contained numerous nerve fibers and terminals. Since this nerve network continued onto the deep muscular plexus (DMP) of the duodenum, we surmised that the numerous nerve fibers in the gastroduodenal junction were specialized DMP in the most proximal part of the duodenum. The innermost layer containing many nerve fibers was about 1,000 microm in length and 100 microm in thickness in the proximal duodenum. This layer contained numerous connective tissue fibers composed of collagen and elastic fibers. Five to 30 smooth muscle cells lay in contact with each other and were surrounded by fine connective tissue. The nerve fibers in the proximal duodenum contained nerve terminals immunoreactive for choline acetyltransferase, dynorphin, enkephalin, galanin, gastrin-releasing peptide, nitric oxide synthase, substance P, and vasoactive intestinal polypeptide. Adrenergic fibers which contained tyrosine hydroxylase immunoreactivity were rare in the proximal duodenum. In the innermost layer of the proximal duodenum, there were numerous c-Kit immunopositive cells that were in contact with nerve terminals. This study allowed us to clarify the specific architecture of the most proximal portion of the duodenum. The functional significance of the proximal duodenum in relation to the electrical connection and neural cooperation of the musculature between the antrum and the duodenum is also discussed.

The phylogenetic distribution, anatomy and histology of the post-cloacal bones and adnexa of geckos.

PubMed

Russell, Anthony P; Vickaryous, Matthew K; Bauer, Aaron M

2016-02-01

Post-cloacal bones of gekkotans may be present as a single (medial) pair, two pairs (medial and lateral), or may be lacking. We, herein, demonstrate that the presence of a single medial pair is the ancestral condition for the Gekkota, that the lateral pair is of sporadic occurrence within and between families, except for the Eublepharidae where it is universal, and that absence is also of sporadic occurrence except for the Sphaerodactylidae where it is the ancestral condition. Adult male Tokay geckos (Gekko gecko) possess only the medial pair of bones, and these exhibit a regionally-specific expression of woven, fibrolamellar, and lamellar bone, and an enclosed medullary cavity. Females and small juvenile males lack bony elements but exhibit a conspicuous band of dense connective tissue located about the anterior and lateral margins of the cloacal sacs. As males grow and attain sexual maturity, the medial post-cloacal bones condense in this band of dense connective tissue, and are thus shown to be dermal ossifications, similar to osteoderms but with muscular associations (although this is also known for crocodylians). Based upon ontogenetic data we set forth a scenario to explain the loss of the medial post-cloacal bones in various lineages. Differential staining of the cloacal sacs failed to reveal any specialized glandular structures. Investigation of the post-cloacal spurs shows them to be associated with cellular connective tissue of a type similar to that found in the vicinity of the medial post-cloacal bones. This suggests that the lateral post-cloacal bones may also be dermal bones, but histological evidence is needed to corroborate this. © 2015 Wiley Periodicals, Inc.

Hypermobility, the Ehlers-Danlos syndromes and chronic pain.

PubMed

Syx, Delfien; De Wandele, Inge; Rombaut, Lies; Malfait, Fransiska

2017-01-01

Chronic widespread pain is a common complaint among individuals affected by generalised joint hypermobility. In the absence of other conditions that cause chronic pain, these individuals are usually diagnosed with joint hypermobility syndrome (JHS). JHS is a multifactorial trait with a strong genetic basis, but no specific genetic markers. Clinical overlap of JHS is seen with heritable connective tissue disorders, particularly with the Ehlers-Danlos syndrome, hypermobile type (hEDS). The Ehlers-Danlos syndromes (EDS) comprise a heterogeneous group of rare monogenic conditions that are characterised by joint hypermobility, skin and vascular fragility and generalised connective tissue friability, and are caused by genetic defects in an array of extracellular matrix genes. The genetic basis of hEDS remains however unknown, in contrast to other well-described EDS subtypes. In view of the considerable clinical overlap with JHS, many consider it and hEDS to be a single clinical entity. Clinical experience and a limited number of clinical studies show that chronic pain also is common in EDS patients, especially in hEDS. The specific underlying causes and mechanisms of pain in JHS and EDS remain poorly understood. Factors likely contributing to the generation and chronicity of pain include nociceptive pain, directly based on structural changes in affected joints, muscle and connective tissue; neuropathic pain; impaired proprioception and muscle weakness; and central sensitisation. These mechanisms are not mutually exclusive, and likely more than one mechanism may be present. Furthermore, anxiety, depression, and other variables may influence the phenotype. Chronic pain in JHS and EDS patients often is inadequately controlled by traditional analgesics and physical therapy. In view of the high prevalence of these underrecognised conditions, future studies addressing the nature and mediators of chronic pain are needed in order to potentially identify novel targets for therapeutic intervention and optimise treatment.

The corpus cavernosum after treatment with dutasteride or finasteride: A histomorphometric study in a benign prostatic hyperplasia rodent model.

PubMed

Da Silva, Marcello H A; Costa, Waldemar S; B Sampaio, Francisco J; De Souza, Diogo B

2018-06-08

Erectile dysfunction is a common side effect of finasteride and dutasteride treatments. The objective of this study was to investigate the structural changes in the penis using a benign prostatic hyperplasia (BPH) rodent model treated with dutasteride or finasteride. Sixty male rats were divided into the following groups: C, untreated control rats; C + D, control rats receiving dutasteride; C + F, control rats receiving finasteride; H, untreated spontaneously hypertensive rats (SHRs); H + D, SHRs treated with dutasteride; and H + F, SHRs treated with finasteride. Treatments were performed for 40 days, and penises were collected immediately thereafter. The organs were analyzed using histomorphometric methods to determine the cross-sectional penile area, as well as the surface density (Sv) of smooth muscle fibers, connective tissue, elastic system fibers, and sinusoidal spaces of the corpus cavernosum. The results were compared using a one-way ANOVA with Bonferroni's posttest. Groups C + D and C + F had a significantly smaller penile cross-sectional area, but more elastic system fiber Sv compared to Group C. Group C + D showed less smooth muscle Sv, and Group H showed more connective tissue but a smaller sinusoidal space Sv in the corpus cavernosum compared to Group C. Groups H + D and H + F had less smooth muscle Sv than Group H. Group H + D also had more connective tissue and elastic system fiber Sv than Group H. Both dutasteride and finasteride promoted penile modifications in the control rat penis, although this affect was greater in Group H animals. In this rodent model, dutasteride was the drug that most affected the corpus cavernosum.

Biomaterial-Mediated Delivery of Degradative Enzymes to Improve Meniscus Integration and Repair

PubMed Central

Qu, Feini; Lin, Jung-Ming G.; Esterhai, John L.; Fisher, Matthew B.; Mauck, Robert L.

2013-01-01

Endogenous repair of fibrous connective tissues is limited, and there exist few successful strategies to improve healing after injury. As such, new methods that advance repair by promoting cell growth, extracellular matrix (ECM) production, and tissue integration would represent a marked clinical advance. Using the meniscus as a test platform, we sought to develop an enzyme-releasing scaffold that enhances integrative repair. We hypothesized that the high ECM density and low cellularity present physical and biologic barriers to endogenous healing, and that localized collagenase treatment might expedite cell migration to the wound edge and tissue remodeling. To test this hypothesis, we fabricated a delivery system in which collagenase was stored inside electrospun poly(ethylene oxide) (PEO) nanofibers and released upon hydration. In vitro results showed that partial digestion of the wound interface improved repair by creating a microenvironment that facilitated cell migration, proliferation, and matrix deposition. Specifically, treatment with high-dose collagenase led to a 2-fold increase in cell density at the wound margin and a 2-fold increase in integrative tissue compared to untreated controls at 4 weeks (p≤0.05). Furthermore, when composite scaffolds containing both collagenase-releasing and structural fiber fractions were placed inside meniscal tears in vitro, enzyme release acted locally and resulted in a positive cellular response similar to that of global treatment with aqueous collagenase. This innovative approach of targeted enzyme delivery may aid the many patients that exhibit meniscal tears by promoting integration of the defect, thereby circumventing the pathologic consequences of partial meniscus removal, and may find widespread application in the treatment of injuries to a variety of dense connective tissues. PMID:23376132

Analysis of the structure of fish lymphocystis disease virions from skin tumours of pleuronectes.

PubMed

Samalecos, C P

1986-01-01

Virions of fish lymphocystis disease (FLDV) from tumour-carrying-fishes (flounder, dab, plaice and gurnard) collected in the North Sea were isolated directly from the tumours and purified by sucrose and subsequent caesium chloride gradient centrifugation. They were studied by electron microscopy using embedding methods, negative staining and using metal shadowing methods. Tumours of dermal connective fish tissue showed particles with hexagonal outlines. Occasionally, an "empty structure" was observed. Subunits of the virus membrane were identified after 3 per cent phosphotungstic acid (PTA) or 0.2 per cent Ruthenium red (RR) staining. FLDV measures 199-227 nm in diameter.

Relative Composition of Fibrous Connective and Fatty/Glandular Tissue in Connective Tissue Grafts Depends on the Harvesting Technique but not the Donor Site of the Hard Palate.

PubMed

Bertl, Kristina; Pifl, Markus; Hirtler, Lena; Rendl, Barbara; Nürnberger, Sylvia; Stavropoulos, Andreas; Ulm, Christian

2015-12-01

Whether the composition of palatal connective tissue grafts (CTGs) varies depending on donor site or harvesting technique in terms of relative amounts of fibrous connective tissue (CT) and fatty/glandular tissue (FGT) is currently unknown and is histologically assessed in the present study. In 10 fresh human cadavers, tissue samples were harvested in the anterior and posterior palate and in areas close to (marginal) and distant from (apical) the mucosal margin. Mucosal thickness, lamina propria thickness (defined as the extent of subepithelial portion of the biopsy containing ≤25% or ≤50% FGT), and proportions of CT and FGT were semi-automatically estimated for the entire mucosa and for CTGs virtually harvested by split-flap (SF) preparation minimum 1 mm deep or after deepithelialization (DE). Palatal mucosal thickness, ranging from 2.35 to 6.89 mm, and histologic composition showed high interindividual variability. Lamina propria thickness (P >0.21) and proportions of CT (P = 0.48) and FGT (P = 0.15) did not differ significantly among the donor sites (anterior, posterior, marginal, apical). However, thicker palatal tissue was associated with higher FGT content (P <0.01) and thinner lamina propria (P ≤0.03). Independent of the donor site, DE-harvested CTG contained a significantly higher proportion of CT and a lower proportion of FGT than an SF-harvested CTG (P <0.04). Despite high interindividual variability in terms of relative tissue composition in the hard palate, DE-harvested CTG contains much larger amounts of CT and much lower amounts of FGT than SF-harvested CTG, irrespective of the harvesting site.

Changes in bone tissue under conditions of hypokinesia and in connection with age

NASA Technical Reports Server (NTRS)

Podrushnyak, E. P.; Suslov, E. I.

1980-01-01

X-ray micrography was used to study the optical density of the blackening of X-ray photographs made of five bones in 9 young people (ages 24 to 29) before and after strict bed rest for 16 to 37 days. Photometric studies of the X-ray film determined the relative concentration of bone structure before and after hypokinesia. In addition, the bone tissues of 25 cadavers of practically healthy individuals (aged 18 to 70) who died from injuries were investigated using X-ray structural analysis. Results show that the reaction to the state of hypokinesia is not uniform in different individuals and is quite often directly reversed. It was established that pronounced osteoporosis can be found in a relatively short time after conditions of hypokinesia in healthy young individuals. Results show that the stabilization of the crystalline structure of hydroxyapatite, especially its crystal formation, is finished by the age of 20 to 25. From 25 to 60, the crystal lattice remains in stable condition but X-ray analysis shows a reduction in the hydroxyapatite density.

In vitro developmental model of the gastrointestinal tract from mouse embryonic stem cells.

PubMed

Torihashi, Shigeko; Kuwahara, Masaki; Kurahashi, Masaaki

2007-10-01

Mouse embryonic stem (ES) cells are pluripotent and retain their potential to form cells, tissues and organs originated from three embryonic germ layers. Recently, we developed in vitro organ--gut-like structures--from mouse ES cells. They had basically similar morphological features to a mouse gastrointestinal tract in vivo composed of three distinct layers (i.e., epithelium, connective tissue and musculature). Gut-like structures showed spontaneous contractions derived from pacemaker cells (interstitial cells of Cajal) in the musculature. We also examined their formation process and expression pattern of transcription factors crucial for gut organogenesis such as Id2, Sox17, HNF3beta/Foxa2 and GATA4. We found that they mimic the development of embryonic gut in vivo and showed a similar expression pattern of common transcription factors. They also maintain their developmental potential after transplantation to a renal capsule. Therefore, gut-like structures are suitable for in vitro models of gastrointestinal tracts and their development. In addition, we pointed out several unique features different from gut in vivo that provide useful and advantageous tools to investigate the developmental mechanism of the gastrointestinal tract.

Broadband diffuse optical characterization of elastin for biomedical applications.

PubMed

Konugolu Venkata Sekar, Sanathana; Beh, Joo Sin; Farina, Andrea; Dalla Mora, Alberto; Pifferi, Antonio; Taroni, Paola

2017-10-01

Elastin is a key structural protein of dynamic connective tissues widely found in the extracellular matrix of skin, arteries, lungs and ligaments. It is responsible for a range of diseases related to aging of biological tissues. The optical characterization of elastin can open new opportunities for its investigation in biomedical studies. In this work, we present the absorption spectra of elastin using a broadband (550-1350nm) diffuse optical spectrometer. Distortions caused by fluorescence and finite bandwidth of the laser source on estimated absorption were effectively accounted for in measurements and data analysis and compensated. A comprehensive summary and comparison between collagen and elastin is presented, highlighting distinct features for its accurate quantification in biological applications. Copyright © 2017 Elsevier B.V. All rights reserved.

Identical twins concordant for pulmonary sequestration communicating with the esophagus and discordant for the VACTERL association.

PubMed

Becker, Julie; Hernandez, Ambrosio; Dipietro, Michael; Coran, Arnold G

2005-07-01

Communicating bronchopulmonary foregut malformations (CBPFMs) are unusual congenital structures composed of a segment of lung tissue connected to the foregut. We present what we believe is the first reported case of identical twins concordant for CBPFM who are discordant for the VACTERL association. Their nonfunctional lung tissue was successfully removed and the fistulae were corrected, and they are expected to live normal life spans. We review the literature concerning these malformations and the proposed theories of their etiology. This case report of concordance in identical twins suggests that a possible genetic component to CBPFMs cannot be ruled out. The discordance for the VACTERL association implies that the etiology is most likely multifactorial.

Pregnancy and autoimmune connective tissue diseases

PubMed Central

Marder, Wendy; Littlejohn, Emily A

2016-01-01

The autoimmune connective tissue diseases predominantly affect women and often occur during the reproductive years. Thus, specialized issues in pregnancy planning and management are commonly encountered in this patient population. This chapter provides a current overview of pregnancy as a risk factor for onset of autoimmune disease, considerations related to the course of pregnancy in several autoimmune connective tissue diseases, and disease management and medication issues before and during pregnancy and the postpartum period. A major theme that has emerged across these inflammatory diseases is that active maternal disease during pregnancy is associated with adverse pregnancy outcomes, and that maternal and fetal health can be optimized when conception is planned during times of inactive disease and through maintaining treatment regimens compatible with pregnancy. PMID:27421217

Scleroderma renal crisis in a case of mixed connective tissue disease.

PubMed

Vij, Mukul; Agrawal, Vinita; Jain, Manoj

2014-07-01

Mixed connective tissue disease (MCTD) is an overlap syndrome first defined in 1972 by Sharp et al. In this original study, the portrait emerged of a connective tissue disorder sharing features of systemic lupus erythematosus, systemic sclerosis (scleroderma) and polymyositis. Scleroderma renal crisis (SRC) is an extremely infrequent but serious complication that can occur in MCTD. The histologic picture of SRC is that of a thrombotic micro-angiopathic process. Renal biopsy plays an important role in confirming the clinical diagnosis, excluding overlapping/superimposed diseases that might lead to acute renal failure in MCTD patients, helping to predict the clinical outcome and optimizing patient management. We herewith report a rare case of SRC in a patient with MCTD and review the relevant literature.