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Collagen Fibers (collagen + fiber)

Distribution by Scientific Domains

Medical Sciences	56%
Life Sciences	26%
Polymers and Materials Science	10%

Distribution within Medical Sciences

Dermatology	23%
Pathology	10%
13 Other Subdomains	67%

Selected Abstracts

Collagen Fiber and Versican Distribution Within the Lamina Propria of Fetal Vocal Folds,

THE LARYNGOSCOPE, Issue 2 2008
Rogerio Borghi Buhler MD
Abstract Objectives: To analyze the presence and distribution of collagen fibers and versican in human vocal fold lamina propria of fetal larynges. Study Design: Cross sectional analysis of cadaveric vocal folds of human fetuses. Methods: Seven fetal larynges obtained from 28- to 36-week-old fetuses were analyzed with the Picrosirius-polarization method, immunohistochemistry, and image analysis. Results: Collagen fibers within the lamina propria exhibited a monolaminar distribution pattern and spatial arrangement in "wicker basket." Versican distribution was larger in the superficial and intermediate layers when compared to the deep layer. Conclusion: Our findings suggest that collagen and versican distribution and arrangement within the lamina propria in the developing fetus are important for vocalization at birth. [source]

The temporal expression and localization of extracellular matrix metalloproteinase inducer (EMMPRIN) during the development of perio-dontitis in an animal model

JOURNAL OF PERIODONTAL RESEARCH, Issue 4 2010
L. Liu
Liu L, Li C, Cai X, Xiang J, Cao Z, Dong W. The temporal expression and localization of extracellular matrix metalloproteinase inducer (EMMPRIN) during the development of periodontitis in an animal model. J Periodont Res 2010; 45: 541,549. © 2010 John Wiley & Sons A/S Background and Objective:, We previously demonstrated extracellular matrix metalloproteinase inducer (EMMPRIN) was associated with the matrix metalloproteinases production of human periodontitis. The aim of this study was to investigate the temporal expression and localization of EMMPRIN during ligature-induced periodontitis in rats. Material and Methods:, Periodontitis was inducd in rats by placing a thread around the cervix of the first mandibular molar. Animals were killed 3, 7, 11, 15 or 21 d after ligation. Mandibles were processed for paraffin sections and stained with hematoxylin and eosin or picrosirius red. The distance from the amelocemental junction to the alveolar crest (ACJ,AC) and the area fraction (Area%) of collagen fibers were measured. EMMPRIN was examined by immunohistochemistry and quantified by positive cell counting. Correlation analyses were then performed. Results:, Histologically, alveolar bone was gradually destroyed from day 3 to 11 and then stabilized. Collagen fibers were slightly dissociated on day 3 and extensively broken on day 7. They were reconstructed from day 11 to 21. EMMPRIN was localized predominantly in infiltrating cells and adjacent fibroblasts in interdental gingiva. The number of EMMPRIN-positive cells increased on day 3, peaked on day 7 and then gradually subsided from day 11 to 21. Statistically, there was a moderate positive correlation regarding the ACJ,AC distance (r = 0.552, p < 0.01) and a strong negative correlation with the Area% of collagen fibers (r = ,0.808, p < 0.01). In gingival epithelium, the immunoreactivity was extremely strong in basal layer cells and sulcular epithelial cells in health. It was greatly enhanced in the inflamed conditions on days 3 and 7. In the interradicular bone, EMMPRIN was localized in the osteoclasts on days 3 and 7, as well as in the osteoblasts from day 11 onwards. Conclusion:, The expression and localization of EMMPRIN are temporally varied during the development of periodontitis. In addition, the inflammation-dependent expression of EMMPRIN might be involved in alveolar bone resorption and collagen breakdown. [source]

Collagen Fiber and Versican Distribution Within the Lamina Propria of Fetal Vocal Folds,

Supramolecular order following binding of the dichroic birefringent sulfonic dye Ponceau SS to collagen fibers

BIOPOLYMERS, Issue 3 2005
B. C. Vidal
Abstract The optical anisotropies (linear dichroism or LD and birefringence) of crystalline aggregates of the sulfonic azo-dye Ponceau SS and of dye complexed with chicken tendon collagen fibers were investigated in order to assess their polarizing properties and similarity to liquid crystals. In some experiments, the staining was preceded by treatment with picric acid. Crystalline fibrous aggregates of the dye had a negative LD, and their electronic transitions were oriented perpendicular to the filamentary structures. The binding of Ponceau SS molecules to the collagen fibers altered the LD signal, with variations in the fiber orientation affecting the resulting dichroic ratios. The long axis of the rod-like dye molecule was assumed to be bound in register, parallel to the collagen fiber. Picric acid did not affect the oriented binding of the azo dye to collagen fibers. There were differences in the optical anisotropy of Ponceau SS-stained tendons from 21-day-old and 41-day-old chickens, indicating that Ponceau SS was able to distinguish between different ordered states of macromolecular aggregation in chicken tendon collagen fibers. In the presence of dichroic rod-like azo-dye molecules such as Ponceau SS, collagen also formed structures with a much higher degree of orientation. The presence of LD in the Ponceau SS-collagen complex even in unpolarized light indicated that this complex can act as a polarizer. © 2005 Wiley Periodicals, Inc. Biopolymers 78: 121,128, 2005 This article was originally published online as an accepted preprint. The "Published Online" date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com [source]

Biocompatibility evaluation of alendronate paste in rat's subcutaneous tissue

DENTAL TRAUMATOLOGY, Issue 2 2009
Graziela Garrido Mori
Therefore, this study aimed to investigate the biocompatibility of experimental alendronate paste in subcutaneous tissue of rats, for utilization in teeth susceptible to root resorption. The study was conducted on 15 male rats, weighing ,180,200 grams. The rats' dorsal regions were submitted to one incision on the median region and, laterally to the incision, the subcutaneous tissue was raised and gently dissected for introduction of two tubes, in each rat. The tubes were sealed at one end with gutta-percha and taken as control. The tubes were filled with experimental alendronate paste. The animals were killed at 7, 15 and 45 days after surgery and the specimens were processed in laboratory. The histological sections were stained with hematoxylin-eosin and analyzed by light microscopy. Scores were assigned to the inflammatory process and statistically compared by the Tukey test (P < 0.05). Alendronate paste promoted severe inflammation process at 7 days, with statistically significant difference compared to the control (P < 0.05%). However, at 15 days, there was a regression of inflammation and the presence of connective tissue with collagen fibers, fibroblasts and blood vessels was observed. After 45 days, it was observed the presence of well-organized connective tissue, with collagen fibers and fibroblasts, and few inflammatory cells. No statistical difference was observed between the control and experimental paste at 15 and 45 days. The experimental alendronate paste was considered biocompatible with subcutaneous tissue of rat. [source]

A Validated Grading Scale for Forehead Lines

DERMATOLOGIC SURGERY, Issue 2008
ALASTAIR CARRUTHERS MD
BACKGROUND As with other facial wrinkles, the gradual loss and disorganization of collagen fibers and elastin, connective tissues that provide underlying support for skin, cause horizontal forehead rhytides in large part. OBJECTIVES To develop the Forehead Lines Grading Scale for objective quantification of horizontal forehead rhytides at rest and with expression and to establish the reliability of this photonumeric scale for clinical research and practice. MATERIALS AND METHODS The Forehead Lines Grading Scale is a 5-point photonumeric rating scale that was developed to objectively quantify resting (static) and hyperkinetic (dynamic) forehead lines. Inter- and intrarater variability was assessed by computing intraclass correlation coefficients. RESULTS The agreement between the experts was highly significant. Bubble plots (bivariate scatter plots) demonstrated linearity in judgment by the experts. CONCLUSION The 5-point photonumeric scale generated spans the severity of forehead lines for which patients commonly seek correction. The scale is well stratified for consistent rating. [source]

Histologic Study of Depressed Acne Scars Treated with Serial High-Concentration (95%) Trichloroacetic Acid

DERMATOLOGIC SURGERY, Issue 8 2006
ANTHONY YUG MD
BACKGROUND Acne scarring is a common manifestation that remains a therapeutic challenge to dermatologists, dermatologic surgeons, and plastic surgeons. Although multiple therapeutic modalities exist, treatment often remains inadequate. The use of high-concentration (95%) trichloroacetic acid (TCA) applied focally to atrophic acne scars has been described. OBJECTIVE The current study confirms the utility of focal application of 95% TCA to acne scars in addition to a histologic examination of this technique. METHODS Acne scars in three patients were treated with focal 95% TCA by serial application. Wooden applicators were used to apply TCA focally and repeated at 6-week intervals for a total of six treatments. Punch biopsies were performed at baseline and at 1 year postoperatively. Histologic examination was performed with routine hematoxylin/eosin, Masson trichrome, and Verhoeff-van Gieson staining. RESULTS Clinical examination revealed apparent cosmetic improvement in both depth and appearance of acne scars. Patient satisfaction was high. Histologic examination demonstrated a decrease in the depth of acne scars. In addition, increased collagen fibers and fragmentation of elastic fibers were noted. There were no complications from the procedure. CONCLUSION Focal application of high-concentration TCA to atrophic and "ice-pick" acne scars appears to produce clinical improvement. Histologic changes of this technique are described. [source]

Medical Potentialities of Biomimetic Apatites through Adsorption, Ionic Substitution, and Mineral/Organic Associations: Three Illustrative Examples,

ADVANCED ENGINEERING MATERIALS, Issue 7 2010
Ahmed Al-Kattan
Biomimetic calcium phosphate apatites are particularly adapted to bio-medical applications due to their biocompatibility and high surface reactivity. In this contribution we report three selected examples dealing with mineral/organic interactions devoted to convey new functionalities to apatite materials, either in the form of dry bioceramics or of aqueous colloids. We first studied the adsorption of risedronate (bisphosphonate) molecules, which present potential therapeutic properties for the treatment of osteoporosis. We then addressed the preparation of luminescent Eu-doped apatites for exploring apatite/collagen interfaces through the FRET technique, in view of preparing "advanced" biocomposites exhibiting close spatial interaction between apatite crystals and collagen fibers. Finally, we showed the possibility to obtain nanometer-scaled apatite-based colloids, with particle size tailorable in the range 30,100,nm by controlling the agglomeration state of apatite nanocrystals by way of surface functionalization with a phospholipid moiety. This paper is aimed at illustrating some of the numerous potentialities of calcium phosphate apatites in the bio-medical field, allowing one to foresee perspectives lying well beyond bone-related applications. [source]

Fibroblast activation protein increases apoptosis, cell adhesion, and migration by the LX-2 human stellate cell line,

HEPATOLOGY, Issue 4 2005
Xin Maggie Wang
Injury and repair in chronic liver disease involve cell adhesion, migration, apoptosis, proliferation, and a wound healing response. In liver, fibroblast activation protein (FAP) has both collagenase and dipeptidyl peptidase IV (DPIV) activities and is expressed only by activated hepatic stellate cells (HSC) and myofibroblasts, which produce and degrade extracellular matrix (ECM). FAP was colocalized with collagen fibers, fibronectin, and collagen type I in human liver. FAP function was examined in vitro by expressing green fluorescent protein FAP fusion protein in cell lines cultured on collagen-I, fibronectin, and Matrigel. Glutamates at 203 and 204 as well as serine624 of FAP were essential for peptidase activity. Human embryonic kidney 293T cells overexpressing FAP showed reduced adhesion and migration. FAP overexpression in the human HSC line LX-2 caused increased cell adhesion and migration on ECM proteins as well as invasion across transwells in the absence or presence of transforming growth factor beta-1. FAP overexpression enhanced staurosporine streptomyces,stimulated apoptosis in both cell lines. Interestingly, the enzyme activity of FAP was not required for these functions. Overexpressing FAP increased the expression of matrix metalloproteinase-2 and CD44 and reduced integrin-,1 expression in 293T cells, suggesting potential pathways of FAP-mediated impairment of cell adhesion and migration in this epithelial cell line. In conclusion, these findings further support a pro-fibrogenic role for FAP by indicating that, in addition to its enzymatic functions, FAP has important nonenzymatic functions that in chronic liver injury may facilitate tissue remodeling through FAP-mediated enhancement of HSC cell adhesion, migration, and apoptosis. Supplementary material for this article can be found on the HEPATOLOGY website (http://www.interscience.wiley.com/jpages/0270-9139/suppmat/index.html). (HEPATOLOGY 2005;42:935,945.) [source]

Two cases of dermatomyofibroma (plaque-like dermal fibromatosis)

INTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 8 2010
Elisabeth Gomez-Moyano MD
Background, Dermatomyofibroma is a rare but distinct benign cutaneous mesenchymal neoplasm of fibroblastic/myofibroblastic differentiation. It is more common in adolescents and young adults, with a female preponderance. In most cases, the lesions are asymptomatic and small, measuring from 10 to 20 mm. Early and active lesions tend to be actin positive. Case report, We present a) a new case of dermatomyofibroma in an 11-month-old male infant, the youngest case reported to date, and b) the second reported case of a giant annular dermatomyofibroma, measuring 10 cm × 6 cm, in a 52-year-old woman. In both cases, histological examination showed a spindle-cell proliferation embedded among the collagen fibers of the dermis, arranged predominantly parallel to the skin surface. In both cases the spindle cells stained positive for smooth muscle actin and the elastic fibers were increased and fragmented. Conclusion, Dermatologists and pediatricians should be aware of this benign entity in order to avoid unnecessary treatment. [source]

Novel 3D collagen scaffolds fabricated by indirect printing technique for tissue engineering

JOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 2 2008
C. Z. Liu
Abstract This article reports the mechanical properties and in vitro evaluation of a collagen scaffold fabricated using an indirect 3D printing technique. Collagen scaffolds, featuring predefined internal channels and capillary networks, were manufactured using phase change printing. It was observed that the collagen scaffolds featured internal channels and a hierarchical structure that varied over length scales of 10,400 ,m. In vitro evaluation using hMSCs demonstrated that the resultant collagen based scaffolds have the ability to support hMSC cell attachment and proliferation; cells can migrate and survive deep within the structure of the scaffold. The cell numbers increased 2.4 times over 28 days in culture for the lysine treated scaffolds. The cells were spread along the collagen fibers to form a 3D structure and extracellular matrix was detected on the surface of the scaffolds after 4 weeks in culture. The crosslinking treatment enhanced the biostability and dynamic properties of the collagen scaffolds significantly. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008 [source]

Modulation of peritendinous adhesion formation by alginate solution in a rabbit flexor tendon model

JOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 1 2007
Jiro Namba
Abstract To examine the antiadhesive effect of an alginate solution following tendon surgery, unilateral subtotal laceration of the flexor digitorum communis tendon was created in one hind limb while the other side was left intact in 32 Japanese white rabbits. The lesion was coated with alginate solution in 16 animals and not coated in the other 16. Degree of adhesion formation was assessed histologically and biomechanically by measuring the flexion angle of the first toe when the flexor digitorum tendon was pulled with a specified force at 4 weeks postoperatively. When compared with the control group, the alginate-treated group demonstrated significantly greater toe flexion, with less scar tissue formation at the repair site. Histologically, complete tendon healing with longitudinal remodeling of collagen fibers was observed in the alginate-treated group, while a random pattern of fibers was observed in the control group. Reduction in adhesion formation using alginate solution represents a novel strategy for the management of tendon injury and repair in the clinical setting. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2007 [source]

Composite coating of bonelike apatite particles and collagen fibers on poly L-lactic acid formed through an accelerated biomimetic coprecipitation process

JOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 2 2006
Yun Chen
Abstract Collagen and apatite were coprecipitated as a composite coating on poly L-lactic acid (PLLA) in an accelerated biomimetic process. The incubation solution contained collagen (1 g/L) and simulated body fluid with 5 times inorganic ionic concentrations as human blood plasma. The coating formed on PLLA films and scaffolds after a 24-h incubation was characterized by using energy-dispersive X-ray spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy (SEM). It was shown that the coating contained carbonated bonelike apatite and collagen, which was similar in composition to natural bone. SEM showed a complex composite coating of submicron bonelike apatite particulates combined with collagen fibrils. It is expected that such biocomposite coating may better facilitate cell interaction and osteoconductivity. This work provided an efficient process to obtain bonelike apatite/collagen composite coating, which is potentially useful in bone tissue engineering. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006 [source]

Regeneration of canine peroneal nerve with the use of a polyglycolic acid,collagen tube filled with laminin-soaked collagen sponge: a comparative study of collagen sponge and collagen fibers as filling materials for nerve conduits

JOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 6 2001
Toshinari Toba
Abstract A novel artificial nerve conduit was developed and its efficiency was evaluated on the basis of promotion of peripheral nerve regeneration across an 80-mm gap in dogs. The nerve conduit was made of a polyglycolic acid,collagen tube filled with laminin-soaked collagen sponge. Conduits filled with either sponge- or fiber-form collagen were implanted into an 80-mm gap of the peroneal nerve (five dogs for each form). Twelve months postoperatively nerve regeneration was superior in the sponge group both morphometrically (percentage of neural tissue: fiber: 39.7 ± 5.2, sponge: 43.0 ± 4.5, n=3) and electrophysiologically (fiber: CMAP 1.06 ± 0.077, SEP 1.32 ± 0.127 sponge: CMAP 1.04 ± 0.106, SEP 1.24 ± 0.197, n=5), although these differences were not statistically significant. The observed regeneration was complementary to successful results reported previously in the same model, in which collagen fibers exclusively were used. The results indicate a possible superiority of collagen sponge over collagen fibers as filling materials. In addition, the mass-producibility, superior scaffolding potential, and capacity for gradual release of soluble factors of the sponge provide make it an attractive alternative to fine fibers, which are both technologically difficult and costly to produce. This newly developed nerve conduit has the potential to enhance peripheral nerve regeneration across longer gaps commonly encountered in clinical settings. © 2001 John Wiley & Sons, Inc. J Biomed Mater Res (Appl Biomater) 58: 622,630, 2001 [source]

Highly Ordered Interstitial Water Observed in Bone by Nuclear Magnetic Resonance,

JOURNAL OF BONE AND MINERAL RESEARCH, Issue 4 2005
Erin E Wilson
Abstract NMR was used to study the nanostructure of bone tissue. Distance measurements show that the first water layer at the surface of the mineral in cortical bone is structured. This water may serve to couple the mineral to the organic matrix and may play a role in deformation. Introduction: The unique mechanical characteristics of bone tissue have not yet been satisfactorily connected to the exact molecular architecture of this complex composite material. Recently developed solid-state nuclear magnetic resonance (NMR) techniques are applied here to the mineral component to provide new structural distance constraints at the subnanometer scale. Materials and Methods: NMR dipolar couplings between structural protons (OH, and H2O) and phosphorus (PO4) or carbon (CO3) were measured using the 2D Lee-Goldburg Cross-Polarization under Magic-Angle Spinning (2D LG-CPMAS) pulse sequence, which simultaneously suppresses the much stronger proton-proton dipolar interactions. The NMR dipolar couplings measured provide accurate distances between atoms, e.g., OH and PO4 in apatites. Excised and powdered femoral cortical bone was used for these experiments. Synthetic carbonate (,2-4 wt%)-substituted hydroxyapatite was also studied for structural comparison. Results: In synthetic apatite, the hydroxide ions are strongly hydrogen bonded to adjacent carbonate or phosphate ions, with hydrogen bond (O-H) distances of ,1.96 Å observed. The bone tissue sample, in contrast, shows little evidence of ordered hydroxide. Instead, a very ordered (structural) layer of water molecules is identified, which hydrates the small bioapatite crystallites through very close arrangements. Water protons are ,2.3-2.55 Å from surface phosphorus atoms. Conclusions: In synthetic carbonated apatite, strong hydrogen bonds were observed between the hydroxide ions and structural phosphate and carbonate units in the apatite crystal lattice. These hydrogen bonding interactions may contribute to the long-range stability of this mineral structure. The biological apatite in cortical bone tissue shows evidence of hydrogen bonding with an ordered surface water layer at the faces of the mineral particles. This structural water layer has been inferred, but direct spectroscopic evidence of this interstitial water is given here. An ordered structural water layer sandwiched between the mineral and the organic collagen fibers may affect the biomechanical properties of this complex composite material. [source]

Effects of high-intensity focused ultrasound on the intervertebral disc: A potential therapy for disc herniations

JOURNAL OF CLINICAL ULTRASOUND, Issue 7 2006
Carina Forslund PhD
Abstract Purpose. To determine the potential application of high-intensity focused ultrasound for the minimally invasive treatment of herniated intervertebral discs by developing a probe that produces sufficiently high temperature locally to shrink collagen fibers (65,75°C). Materials and Methods. A 5-mm ultrasound probe was produced with a geometric focal length of 15 mm. The probe produced 2.5 W of acoustic power and was operated at a frequency of 4.1 MHz. Measurements of temperature increase were performed in discs from bovine tails. In vivo experiments were performed to assess histologic changes in the disc as well as in nerve root and muscle. Results. Sufficient temperature increase to produce collagen shrinkage was observed close to the focus of the ultrasound. Temperature measurements in vertebral end plates showed a temperature increase of only 4°C after 60-second exposure of the disc. In vivo experiments revealed histologic changes in the disc consistent with collagen shrinkage, with no adverse effects seen in surrounding tissues. Conclusions. The experiments demonstrated the feasibility of high-intensity focused ultrasound in the treatment of contained herniated discs. This technique has several advantages over other thermal treatment modalities. © 2006 Wiley Periodicals, Inc. J Clin Ultrasound 34:330,338, 2006 [source]

Prurigo nodularis: systematic analysis of 58 histological criteria in 136 patients

JOURNAL OF CUTANEOUS PATHOLOGY, Issue 5 2010
Nils Weigelt
Background: To date, there has been no systematic investigation of the detailed histological features of prurigo nodularis (PN) in a large cohort of patients. Methods: This retrospective study includes skin biopsies of 136 patients (63 males, 73 females; mean age: 58.38 years) with PN. Results: Highly characteristic for PN is the presence of thick compact orthohyperkeratosis; the hairy palm sign (folliculosebaceous units in nonvolar skin in conjunction with a thick and compact cornified layer, like that of volar skin); irregular epidermal hyperplasia or pseudoepitheliomatous hyperplasia; focal parakeratosis; hypergranulosis; fibrosis of the papillary dermis with vertically arranged collagen fibers; increased number of fibroblasts and capillaries; a superficial, perivascular and/or interstitial inflammatory infiltrate of lymphocytes, macrophages and, to a lesser extent, eosinophils and neutrophils. For comparison, histological findings in 45 patients (18 males, 27 females; mean, 55.64 years) with lichen simplex (LS) were studied. PN and LS, both of them scratch-induced, had 50 of 58 (86.2%) histological features in common. Conclusions: PN revealed a characteristic histological pattern. Absence of pseudoepitheliomatous hyperplasia or nerve fiber thickening, however, does not rule out the histological diagnosis of PN. A correlation of clinical and histological findings is necessary to reliably distinguish between PN and LS. Weigelt N, Metze D, Ständer S. Prurigo nodularis: systematic analysis of 58 histological criteria in 136 patients. [source]

Fibroblastic rheumatism: fibromatosis rather than non-Langerhans cell histiocytosis

JOURNAL OF CUTANEOUS PATHOLOGY, Issue 5 2010
Nicolas Kluger
Background: Fibroblastic rheumatism is a unique fibro-proliferative disease affecting the skin and joints. It is characterized by distinctive clinical and histological features related to benign spindle-shaped cells proliferation. Pediatric reports are scarce in the literature. Objective: We describe here a new case in a 10-year-old boy and discuss the potential origin of the cell proliferation. Methods: Clinical findings, radiology, microscopic examination and outcome are reviewed. Histopathology and immunochemistry studies were performed on skin biospies using CD68, CD163, desmin, factor XIIIa, CD34, smooth muscle actin, PS100, epithelial membrane antigen, and calponin. Results: Histological sections disclosed a rather circumscribed nonencapsulated nodular infiltrate, invading the dermis and the upper subcutaneous tissue, consisted of a proliferation of spindle or stellate-shaped cells and thickened collagen fibers. Orcein staining showed disappearance of the elastic network. Aponeurosis and muscle were normal. A mild perivascular lymphohistiocytic infiltrate was noted. Calponin-staining was less strongly expressed as SMA, and some of them but not all were CD68 positive, as well. On the other hand, all were CD34, CD163, FXIIIa, PS100, EMA and desmin-negative. Conclusion: The true origin of these cells remains unclear. Some authors have speculated a histiocytic origin. However, immuno-chemical staining in our case failed to confirm this hypothesis and instead supported a fibroblastic/myofibroblastic origin. Given the clinical course and the histological and immunohistochemical results, we suggest that FR should be added to the group of fibromatoses. Kluger N, Dumas-Tesici A, Hamel D, Brousse N, Fraitag S. Fibroblastic rheumatism: fibromatosis rather than non-Langerhans cell histiocytosis. [source]

CD34+ Pigmented Fibrous Proliferations: The Morphologic Overlap Between Pigmented Dermatofibromas and Bednar Tumors

JOURNAL OF CUTANEOUS PATHOLOGY, Issue 1 2005
J. Chu McAllister
Pigmented dermatofibrosarcoma protuberans (Bednar tumor) constitute 5,10% of all cases of dermatofibrosarcoma protuberans, and are usually considered mimics of melanocytic proliferations rather than fibrous lesions. We report two cases of pigmented fibrous proliferations that demonstrate features of both dermatofibromas and DFSP. The first case is a 19-year-old man with a three year history of a slowly growing pigmented lesion on the right arm. On clinical exam the lesion was a 7 mm firm pigmented papulonodular lesion. The second case is a 31-year-old woman with a 4,5 year history of a slowly enlarging, asymptomatic ,dark area' on the right buttock. On clinical exam the lesion is a 2 cm darkly pigmented flat nodule. Morphologically both lesions are primarily dermal proliferations of spindled cells admixed with pigmented dendritic melanocytes. The lesional cells trap collagen fibers at the periphery and there is basal cell hyperpigmentation. Adnexal structures are effaced but significant trapping of subcutaneous fat is not present. By immunohistochemistry both lesions show focal CD34 positivity but are negative for Factor XIIIa and melanocytic markers. Although overlap between dermatofibromas and DFSP is well documented in the literature, pigmented fibrous lesions with features of both entities are not well described. [source]

Fibroepithelioma-like changes occurring in perianal Paget's disease with rectal mucinous carcinoma: case report and review of 49 cases of extramammary Paget's disease

JOURNAL OF CUTANEOUS PATHOLOGY, Issue 3 2002
Akemi Ishida-Yamamoto
Background:, Anogenital Paget's disease (PD) may be accompanied by varying degrees of epidermal hyperplasia. The histological changes can be reminiscent of fibroepithelioma of Pinkus. Methods:, We present a case of perianal PD associated with fibroepitheliomatous epidermal hyperplasia in a 76-year-old-man with an underlying rectal mucinous carcinoma. We also carried out a retrospective analysis of 51 biopsies from 49 cases of extramammary PD to see whether particular epidermal changes occur in association with PD in different anatomic locations. Results:, A tumor, 3 cm in diameter, was noted in the patient's perianal skin. Histologically, it was composed of anastomosing thin epithelial strands with follicular differentiation. Paget's cells were distributed in the epithelial strands of this tumor as well as in the surrounding epidermis and anal epithelia. In our series of extramammary PD, epidermis was hyperplastic in two of two perianal cases, 26 of 43 genital skin samples, and one of six axillary PD biopsies. The stroma beneath the hyperplastic epidermis tended to be rich in thin collagen fibers and fibroblasts. Conclusions:, Anogenital PD was more frequently associated with epidermal hyperplasia than axillary PD. Fibroepitheliomatous hyperplasia may be induced by the altered stroma associated with PD. [source]

Preliminary study of chemical bile duct embolization to treat hepatolithiasis in rabbits

JOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 6 2006
Fu Yu Li
Abstract Background:, The high recurrence rate of hepatolithiasis is still a problem to be solved. The purpose of the present study was therefore to carry out a preliminary study of the practical value of chemical bile duct embolization (CBDE) to treat hepatolithiasis in rabbits. Methods:, Chemical bile duct embolization was performed with phenol or absolute ethanol along with N -butyl-cyanoacrylate. The feasibility and effectiveness of CBDE for chemical hepatectomy was assessed by investigating histological changes, biochemistry for hydroxyproline and in situ hybridization for collagen I. Results:, Histologically, the mucosal epithelia of the embolized bile ducts were entirely replaced by collagen fibers, thus effectively eradicating chronic proliferative cholangitis. Also of note, the diseased biliary duct lumens were completely filled with N -butyl-cyanoacrylate, thus effectively preventing calculus formation. The hepatocytes also disappeared completely in the periphery of the embolized lobe, demonstrating that the desired effects of chemical hepatectomy were achieved through CBDE. In a further comparison of embolizing agents, the phenol-cyanoacrylate embolized livers and bile ducts had a higher level of hydroxyproline and collagen I than those embolized with ethanol plus cyanoacrylate. Conclusion:, Chemical bile duct embolization is a promising approach to prevent the recurrence of hepatolithiasis and to achieve the effect of chemical hepatectomy. [source]

The musculotendinous system of an anguilliform swimmer: Muscles, myosepta, dermis, and their interconnections in Anguilla rostrata

JOURNAL OF MORPHOLOGY, Issue 1 2008
Nicole Danos
Abstract Eel locomotion is considered typical of the anguilliform swimming mode of elongate fishes and has received substantial attention from various perspectives such as swimming kinematics, hydrodynamics, muscle physiology, and computational modeling. In contrast to the extensive knowledge of swimming mechanics, there is limited knowledge of the internal body morphology, including the body components that contribute to this function. In this study, we conduct a morphological analysis of the collagenous connective tissue system, i.e., the myosepta and skin, and of the red muscle fibers that sustain steady swimming, focusing on the interconnections between these systems, such as the muscle-tendon and myosepta-skin connections. Our aim is twofold: (1) to identify the morphological features that distinguish this anguilliform swimmer from subcarangiform and carangiform swimmers, and (2) to reveal possible pathways of muscular force transmission by the connective tissue in eels. To detect gradual morphological changes along the trunk we investigated anterior (0.4L), midbody (0.6L), and posterior body positions (0.75L) using microdissections, histology, and three-dimensional reconstructions. We find that eel myosepta have a mediolaterally oriented tendon in each the epaxial and hypaxial regions (epineural or epipleural tendon) and two longitudinally oriented tendons (myorhabdoid and lateral). The latter two are relatively short (4.5,5% of body length) and remain uniform along a rostrocaudal gradient. The skin and its connections were additionally analyzed using scanning electron microscopy (SEM). The stratum compactum of the dermis consists of ,30 layers of highly ordered collagen fibers of alternating caudodorsal and caudoventral direction, with fiber angles of 60.51 ± 7.05° (n = 30) and 57.58 ± 6.92° (n = 30), respectively. Myosepta insert into the collagenous dermis via fiber bundles that pass through the loose connective tissue of the stratum spongiosum of the dermis and either weave into the layers of the stratum compactum (weaving fiber bundles) or traverse the stratum compactum (transverse fiber bundles). These fiber bundles are evenly distributed along the insertion line of the myoseptum. Red muscles insert into lateral and myorhabdoid myoseptal tendons but not into the horizontal septum or dermis. Thus, red muscle forces might be distributed along these tendons but will only be delivered indirectly into the dermis and horizontal septum. The myosepta-dermis connections, however, appear to be too slack for efficient force transmission and collagenous connections between the myosepta and the horizontal septum are at obtuse angles, a morphology that appears inadequate for efficient force transmission. Though the main modes of undulatory locomotion (anguilliform, subcarangiform, and carangiform) have recently been shown to be very similar with respect to their midline kinematics, we are able to distinguish two morphological classes with respect to the shape and tendon architecture of myosepta. Eels are similar to subcarangiform swimmers (e.g., trout) but are substantially different from carangiform swimmers (e.g., mackerel). This information, in addition to data from kinematic and hydrodynamic studies of swimming, shows that features other than midline kinematics (e.g., wake patterns, muscle activation patterns, and morphology) might be better for describing the different swimming modes of fishes. J. Morphol., 2008. © 2007 Wiley-Liss, Inc. [source]

An ultrastructural study of the cuticle in the marine annelid Heterodrilus (Tubificidae, Clitellata)

JOURNAL OF MORPHOLOGY, Issue 1 2008
Erica Sjölin
Abstract The ultrastructure of the cuticle in four species of the marine Heterodrilus (H. paucifascis, H. pentcheffi, H. flexuosus, H. minisetosus) is investigated with transmission electron microscopy. The noncellular cuticle consists of several parts; closest to the epidermis is a thick zone of collagen fibers embedded in a matrix. The matrix continues outside the fiber zone, forming a layered epicuticle. The external surface of the epicuticle is covered by evenly distributed, membrane-bound bodies, termed epicuticular projections. The epicuticular projections have their longitudinal axis perpendicular to the surface of the cuticle and are attached to the surface by either the surrounding membrane itself or by short pedestals. Microvilli, extensions from the epidermal cells, penetrate and sometimes pass completely through the cuticle. There is interspecific variation in the morphology of the cuticle. The four studied species differ in the arrangement of the collagen fibers, from irregularly distributed fibril bundles to orthogonally arranged fiber layers, as well as in the number and density of layers in the epicuticle. One of the studied species, H. paucifascis, shows intraspecific variation, which is associated with sample locality. The Bahamian specimens of H. paucifascis have four layers in the epicuticle, club-shaped epicuticular projections, and collagen fibers forming a less defined orthogonal grid, while the Belizean specimens have three layers in the epicuticle, epicuticular projections with a bulging part at midlevel, and a distinct orthogonal grid. Based on these findings the variation in the morphology of the cuticle appears to be dependent on both phylogenetic constraints, and functional and environmental factors. J. Morphol., 2008. © 2007 Wiley-Liss, Inc. [source]

Jaw bone remodeling at the invasion front of gingival squamous cell carcinomas

JOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 1 2003
Masahiro Ito
Abstract Background:, It is still unknown how jaw bone remodeling occurs at actual invasion sites of oral squamous cell carcinomas. Since there is no other human carcinomas which make a direct invasion of the bone, gingival carcinomas are valuable examples. Methods:, Twelve surgical specimens of gingival squamous cell carcinoma were examined histopathologically and immunohistochemically for remodeling of bone and its surrounding tissue. Results:, Three types of bone interfaces with carcinomatous invasion were distinguished. These included areas with bone resorption, smooth bone surface and new bone formation. In the bone-resorption area, numerous osteoclasts were located along the bone surface, which was surrounded by myxoid stroma. The myxoid stroma was characterized by immunopositivity for heparan sulfate proteoglycan (HSPG), abundant vascularity and macrophagic infiltration. In the bone-formation area, rows of osteoblasts were aligned on the bone surface. The stroma around osteoblasts was also HSPG-immunopositive, poor in vascularity but rich in activated fibroblasts. In the smooth-bone area, the stroma showed an organizing phase of granulation tissue with slender fibroblasts and mature collagen fibers but with less vascularity and inflammatory infiltrates. Conclusion:, The results indicate that the stromal architecture, especially in terms of its inflammatory cellular, vascular and matrix compositions, is strictly regulated in the timing and site of jaw bone remodeling which is causes by carcinomatous invasion. [source]

Multilayer tendon slices seeded with bone marrow stromal cells: A novel composite for tendon engineering

JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 7 2009
Hiromichi Omae
Abstract The ideal scaffold for tendon engineering would possess the basic structure of the tendon, native extracellular matrix, and capability of cell seeding. The purpose of this study was to assess the tissue engineering potential of a novel composite consisting of a decellularized multilayer sliced tendon (MST) scaffold seeded with bone marrow stromal cells (BMSC). BMSC and infraspinatus tendons were harvested from 20 dogs. The tendons were sectioned in longitudinal slices with a thickness of 50 µm. The slices were decellularized, seeded with BMSC, and then bundled into one composite. The composite was incubated in culture media for 14 days. The resulting BMSC-seeded MST was evaluated by qRT-PCR and histology. The BMSC viability was assessed by a fluorescent tracking marker. Histology showed that the seeded cells aligned between the collagen fibers of the tendon slices. Analysis by qRT-PCR showed higher tenomodulin and MMP13 expression and lower collagen type I expression in the composite than in the BMSC before seeding. BMSC labeled with fluorescent tracking marker were observed in the composite after culture. Mechanical testing showed no differences between scaffolds with or without BMSC. BMSC can survive in a MST scaffold. The increased tenomodulin expression suggests that BMSC might express a tendon phenotype in this environment. This new composite might be useful as a model of tendon tissue engineering. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27: 937,942, 2009 [source]

Collagen orientation in periosteum and perichondrium is aligned with preferential directions of tissue growth

JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 9 2008
Jasper Foolen
Abstract A feedback mechanism between different tissues in a growing bone is thought to determine the bone's morphogenesis. Cartilage growth strains the surrounding tissues, eliciting alterations of its matrix, which in turn, creates anisotropic stresses, guiding directionality of cartilage growth. The purpose of this study was to evaluate this hypothesis by determining whether collagen fiber directions in the perichondrium and periosteum align with the preferential directions of long bone growth. Tibiotarsi from chicken embryos across developmental stages were scanned using optical projection tomography (OPT) to assess preferential directions of growth at characteristic sites in perichondrium and periosteum. Quantified morphometric data were compared with two-photon laser-scanning microscopy images of the three-dimensional collagen network in these fibrous tissues. The diaphyseal periosteum contained longitudinally oriented collagen fibers that aligned with the preferential growth direction. Longitudinal growth at both metaphyses was twice the circumferential growth. This concurred with well-developed circumferential fibers, which covered and were partly interwoven with a dominant network of longitudinally oriented fibers in the outer layer of the perichondrium/periosteum at the metaphysis. Toward both articulations, the collagen network of the epiphyseal surface was randomly oriented, and growth was approximately biaxial. These findings support the hypothesis that the anisotropic architecture of the collagen network, detected in periosteum and perichondrium, concurs with the assessed growth directions. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:1263,1268, 2008 [source]

Experimental and model determination of human intervertebral disc osmoviscoelasticity

JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 8 2008
Y. Schroeder
Abstract Finite element (FE) models have become an important tool to study load distribution in the healthy and degenerated disc. However, model predictions require accurate constitutive laws and material properties. As the mechanical properties of the intervertebral disc are regulated by its biochemical composition and fiber-reinforced structure, the relationship between the constitutive behavior of the tissue and its composition requires careful consideration. While numerous studies have investigated the annulus fibrosus compressive and tensile properties, specific conditions required to determine model parameters for the osmoviscoelastic model are unavailable. Therefore, the objectives of this study were (1) to complement the existing material testing in the literature with confined compression and tensile tests on human annulus fibrosus and (2) to use these data, together with existing nucleus pulposus compression data to tune a composition-based, osmoviscoelastic material constitutive law. The osmoviscoelastic material constitutive law and the experimental data were used to describe the fiber and nonfiber properties of the human disc. The compressive material properties of normal disc tissue were Gm,=,1.23 MPa, M,=,1.57, and ,,=,1.964,×,10,16 m4/Ns; the tensile fiber material parameters were E0,=,77.0 MPa; E,,=,500 MPa, and ,,=,1.8,×,103 MPa,s. The goodness of fit ranged from 0.88 to 0.96 for the four experimental conditions evaluated. The constitutive law emphasized the interdependency of the strong swelling ability of the tissue and the viscoelastic nature of the collagen fibers. This is especially important for numerical models to further study the load sharing behavior with regard to disc degeneration and regeneration. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:1141,1146, 2008 [source]

Use of a bioscaffold to improve healing of a patellar tendon defect after graft harvest for ACL reconstruction: A study in rabbits

JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 2 2008
Sinan Karaoglu
Abstract Following harvest of a bone-patellar tendon-bone (BPTB) autograft, the central third of the patellar tendon (PT) does not heal well. The healing tissues also form adhesions to the fat pad and can cause abnormal patellofemoral joint motion. The hypotheses were that a bioscaffold could enhance patellar tendon healing through contact guidance and chemotaxis, and the scaffold could serve as a barrier to decrease adhesion formation between the neo-PT and infrapatellar fat pad. In 20 New Zealand White rabbits, a central-third PT defect was created. One strip of porcine small intestinal submucosa (SIS) was attached to both the anterior and posterior sides of the PT defect of the SIS-treated group (n,=,10). For comparison, a central defect was left nontreated (n,=,10). At 12 weeks, histomorphology was examined using Masson's trichrome staining. The cross-sectional area (CSA) was determined with a laser micrometer, and the central BPTB complexes were tested in uniaxial tension. SIS-treated samples showed a greater amount of healing tissue with denser and well-oriented collagen fibers and more spindle-shaped cells. There was no noticeable adhesion formation in the SIS-treated group. For the nontreated group, there were significantly more and diffuse adhesive formations. The SIS-treated group also had a 68% increase in neo-PT CSA, 98% higher stiffness, and 113% higher ultimate load than that in the nontreated group. SIS treatment increased the quantity of healing tissue, improved the histological appearance and biomechanical properties of the neo-PT, and prevented adhesion formation between the PT and fat pad. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:255,263, 2008 [source]

Achilles Detachment in Rat and Stable Gastric Pentadecapeptide BPC 157: Promoted Tendon-to-Bone Healing and Opposed Corticosteroid Aggravation

JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 5 2006
Andrija Krivic
Abstract Stable gastric pentadecapeptide BPC 157 (BPC 157, as an antiulcer agent in clinical trials for inflammatory bowel disease; PLD-116, PL 14736, Pliva, no toxicity reported) alone (without carrier) ameliorates healing of tendon and bone, respectively, as well as other tissues. Thereby, we focus on Achilles tendon-to-bone healing: tendon to bone could not be healed spontaneously, but it was recovered by this peptide. After the rat's Achilles tendon was sharply transected from calcaneal bone, agents [BPC 157 (10 µg, 10 ng, 10 pg), 6,-methylprednisolone (1 mg), 0.9% NaCl (5 mL)] were given alone or in combination [/kg body weight (b.w.) intraperitoneally, once time daily, first 30-min after surgery, last 24 h before analysis]. Tested at days 1, 4, 7, 10, 14, and 21 after Achilles detachment, BPC 157 improves healing functionally [Achilles functional index (AFI) values substantially increased], biomechanically (load to failure, stiffness, and Young elasticity modulus significantly increased), macro/microscopically, immunohistochemistry (better organization of collagen fibers, and advanced vascular appearance, more collagen type I). 6,-Methylprednisolone consistently aggravates the healing, while BPC 157 substantially reduces 6,-methylprednisolone healing aggravation. Thus, direct tendon-to-bone healing using stabile nontoxic peptide BPC 157 without a carrier might successfully exchange the present reconstructive surgical methods. © 2006 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res [source]

Long-term effects of porcine small intestine submucosa on the healing of medial collateral ligament: A functional tissue engineering study

JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 4 2006
Rui Liang
Abstract Porcine small intestinal submucosa (SIS) was previously shown to enhance the mechanical properties of healing medial collateral ligaments (MCL), and the histomorphological appearance and collagen type V/I ratio were found to be close to those of normal MCL. We hypothesized that at a longer term, 26 weeks, SIS could guide a better organized neo-ligament formation, increasing mechanical properties and increasing collagen fibril diameters mediated by a reduction in collagen type V. A 6 mm gap injury in the right MCL was surgically created in 38 rabbits, while the contralateral intact MCL served as a sham-operated control. In half the animals, a strip of SIS was sutured onto the severed ends. In the other half, no SIS was applied. The cross-sectional area (CSA) was determined with a laser micrometer system. The femur,MCL,tibia complex was mechanically tested in uniaxial tension. Histomorphology was determined through H&E and immunofluorescent staining and transmission electron microscopy (TEM). Sodium-dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) was used to determine collagen type V/I ratio. SIS-treated MCLs displayed a 28% reduction in CSA, a 33% increase in tangent modulus, and a 50% increase in tensile strength compared with the nontreated group (p,<,0.05). TEM showed groups of collagen fibrils with larger diameters in the SIS-treated ligaments in comparison with uniformly small fibrils for the nontreated group. H&E staining showed more densely stained collagen fibers in the SIS-treated group aligned along the longitudinal axis with more interspersed spindle-shaped cells. Immunofluorescent staining showed less collagen type V signals, confirmed by a 5% lower ratio of collagen type V/I compared with the nontreated controls (p,<,0.05). The findings extend the shorter term 12-week results, and support the potential of porcine SIS as a bioscaffold to enhance ligament healing. © 2006 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res [source]