Dense Collagenous Tissue Research Articles

Spindle-cell liposarcoma: a rare variant of liposarcoma arising in the foot

Liposarcoma is the most common soft-tissue sarcoma, accounting for 20% of all mesenchymal malignancies [1]. We report a rare histological variant arising from the dorsum of the foot. A 55-year-old woman presented with a slow-growing, well-defined swelling on the dorsum of the foot. Histological examination after complete excision showed a tumour with zones of dense collagenous tissue containing pleomorphic spindle cells and scattered atypical adipocytes. A diagnosis of spindle-cell sarcoma was made, and the woman was referred to the local sarcoma unit.

A histomorphological study of tendon reconstruction to a hydroxyapatite-coated implant: regeneration of a neo-enthesis in vivo

The attachment of tendons and ligaments to massive endoprostheses remains a clinical challenge due to the difficulty in achieving a soft tissue implant interface with a mechanical strength sufficient to transmit the forces necessary for locomotion. We have used an in vivo animal model to study patellar tendon attachment to an implant surface. The interface generated when the patellar tendon was attached to a hydroxyapatite (HA) coated implant was examined using light microscopy and a quantitative histomorphological analysis was performed. In the Autograft Group, the interface was augmented with autogenous cancellous bone and marrow graft, and at six weeks an indirect-like insertion was observed. At twelve weeks, the interface was observed to be a layered neo-enthesis, whose morphology was similar to a normal direct tendon insertion. In the HA Group, the tendon–implant interface was not augmented, and the implant was enveloped by a dense collagenous fibrous tissue. This study shows that a tendon–implant neo-enthesis can develop in situ by employing a suitable implant surface in association with biological augmentation.

Age-related changes of collagenous fibers in the human vocal fold mucosa.

The viscoelastic properties of the vocal fold mucosa depend on the extracellular matrices. Collagenous fibers provide tensile strength and resilience and serve as a stabilizing scaffold in the extracellular matrices. Light and electron microscopic investigations of age-related changes of collagenous fibers in vocal fold mucosa were carried out on excised normal human adult larynges. Twelve human vocal fold mucosae were examined (10 from older adults with ages ranging from 70 to 97 years, and 2 from younger adults for comparison). The results for the aged mucosae can be summarized as follows. 1) Especially in men, collagenous fibers had increased and reticular fibers had decreased. 2) Collagenous fibers had formed bundles, and their density was high. 3) The spaces between collagenous fibers and the interstitial spaces for other extracellular matrices had decreased. 4) The collagenous fibril diameters differed, and their outline was irregular. 5) Twisted collagenous fibrils were present. 6) Occasionally, masses of dense collagenous fibers and fibrous tissue could be seen in the mucosa. 7) Occasionally, the collagenous fibers were increased all the way from the deep layer to the superficial layer of the mucosa, and consequently, there was no layered structure. Not only changes in the 3-dimensional structure of the collagenous fibers, but also their qualitative and quantitative changes, have an effect on the 3-dimensional structure of the extracellular matrices. Thus, the viscoelasticity must change to ensure normal phonation, and this change in viscoelasticity would explain one component of aging of the voice.

Osteochondral reconstruction of a non-weight-bearing joint using a high-density porous polyethylene implant.

Currently, there is no reliable reconstructive modality allowing anatomic resurfacing of traumatic digital osteochondral articular defects. The purpose of the present study is to demonstrate the utility of Medpor, a high-density porous polyethylene (HDPP) scaffold biomaterial that can (1) be readily contoured to fit any joint defect, (2) permit stable internal fixation, and (3) permit osteocyte and chondrocyte ingrowth and subsequent articular cartilage resurfacing necessary to restore joint congruity. HDPP has gained wide acceptance for use in craniofacial and skeletal reconstruction and augmentation. An avian non-weight-bearing joint model was designed to study the role of the HDPP implant in small joint reconstruction. An osteochondral defect was created with a 5-mm circular punch in the humeral articular surface of both glenohumeral joints of 32 adult White Leghorn chickens. In each animal, one defect was press-fitted with a correspondingly sized HDPP implant (HDPP implant group); the contralateral defect was filled with the original osteochondral plug (isograft group) or left unrepaired (control group). At 2 weeks, and 1, 3, and 6 months,joints from each group were harvested and evaluated. Over the 6-month study period, joints in the control group demonstrated healing with dense collagenous scar tissue leaving residual defects at the articular surfaces and significant degenerative disease of the glenohumeral joints radiographically. Joints in the isograft group demonstrated near-complete resorption with some preservation of the cartilaginous cap but overall depression of the articular surface and significant degenerative joint disease. Joints in the HDPP implant group demonstrated stable fixation by highly mineralized bony trabecular ingrowth, preservation of the articular contour of the humeral head, and no evidence of significant degenerative joint disease. These findings indicate a potential role for this high-density porous polyethylene implant in the reconstruction of small joint articular and osseous defects.

Nasal Glial Heterotopia

2-month-old boy was evaluated for a subcutaneous mass on the right dorsum of his nose. On physical examination, the mass was rubbery, extended into the nasal cavity, and impinged on the nasal septum. The child underwent surgery, with a preoperative diagnosis of cyst. During surgical exploration, the surgeons noted that the mass deviated the nasal septum to the left and that the right nasal bone was absent. The excised specimen was described as an irregular and rubbery piece of tan-pink soft tissue, which measured 1.5 cm in greatest dimension. Routine hematoxylin-eosin‐stained sections revealed a poorly circumscribed submucosal mass. A subtle interdigitating trabecular pattern was evident, with alternating bundles of dense collagenous tissue and a slightly more cellular and disorganized population of cells with ovoid or irregular nuclei and a fibrillary stroma (Figure, left). The Masson trichrome stain (Figure, right) emphasized this pattern, staining the collagen intensely blue and the intersecting cellular population red. A positive immunohistochemical reaction with glial fibrillary acidic protein (Figure, inset) confirmed the diagnosis of glial heteroto

Expression and Action of Hepatocyte Growth Factor in Human and Bovine Normal Ovarian Surface Epithelium and Ovarian Cancer1

More than 95% of ovarian cancers originate from the epithelial cells on the surface of the ovary, which are termed ovarian surface epithelium (OSE). These OSE cells are modified peritoneal mesothelial cells separated from underlying ovarian surface stromal tissue by a basal lamina of dense collagenous connective tissue. Mesenchymal-epithelial cell interactions between stromal cells and OSE cells are postulated to be important for normal OSE biology and for the onset of ovarian cancer. Hepatocyte growth factor (HGF) is a mesenchymal-derived growth factor that mediates mesenchymal-epithelial cell interactions in a number of different tissues. The current study was an investigation of the expression and actions of HGF in normal OSE and ovarian cancer. Human epithelial cells from borderline and stage III ovarian cancer cases were found to express HGF protein in the epithelial cell component by immunocytochemistry analysis. The stromal cell component of human ovarian tumors contained little or no HGF immunostaining. Normal bovine ovaries have a similar physiology and endocrinology to human ovaries and are used as a model system to investigate normal OSE functions. HGF protein was detected in the OSE from both normal human and bovine ovaries. Adjacent ovarian stromal tissue contained light but positive HGF immunostaining. RNA was collected from normal bovine ovarian stromal cells to examine HGF gene expression. HGF transcripts were detected in cultured OSE and stromal cells by Northern blot analysis. Using a quantitative reverse transcription-polymerase chain reaction procedure, HGF gene expression was found to be high in freshly isolated OSE but low in freshly isolated stroma. Levels of HGF gene expression after culture of stroma increased. Observations indicate that normal OSE express high levels of HGF in vivo and in vitro. Expression of HGF by normal epithelial cells versus stromal cells was unexpected and suggests that HGF may be important in an autocrine regulation of OSE. HGF actions on normal OSE cells and ovarian cancer cells were investigated. HGF was found to stimulate the growth of normal OSE cells in a manner similar to such growth stimulated by epidermal growth factor. Two ovarian cancer cell lines, SKOV3 and OCC1, were also stimulated to grow in response to HGF. This observation suggests that HGF may be involved in sustaining growth of ovarian tumors. These results are the first to demonstrate the production and action of HGF in normal OSE cells and ovarian cancer cells. This appears to be an example of HGF production by an epithelial cell, such that a mesenchymal-epithelial mixed phenotype is present. The autocrine stimulation of OSE growth by the local production and action of HGF provides insight into how the OSE may develop abnormal growth characteristics involved in the onset and progression of ovarian cancer.

Malignant Adenomyoepithelioma of the Breast With Mixed Osteogenic, Spindle Cell, and Carcinomatous Differentiation

A 50-year-old woman had a malignant tumor of the left breast, which recurred twice, metastasized, and caused death after 39 months. Histologically, the original neoplasm and the first recurrence comprised an adenomyoepithelioma, in addition to a sarcoma composed of trabeculae of mature and immature bone, osteoid, and partly calcified, dense collagenous tissue. The trabeculae were lined by alpha-smooth muscle actin-positive mononuclear tumor cells, which also extended into the stroma. Similarly, scattered osteoclastlike, multinucleate giant cells were present in the stroma and in the region of the trabeculae. This same pattern of adenomyoepithelioma and osteosarcoma also was seen in the last recurrence, together with a proliferation of undifferentiated malignant spindle-shaped cells. The last biopsy also contained a separate small focus of invasive ductal carcinoma of usual type. It was concluded that this, apparently unique, tumor probably represented an adenomyoepithelioma in which a metaplastic sarcoma of osteogenic and undifferentiated types developed from the myoepithelial element, and in which a carcinoma developed from the epithelial component.

경부의 거대한 단발성 신경섬유종 1례

A neurofibroma is a tumor of the nerve sheath. The neurofibroma originates from the Schwann cells, which produce the perineural connective tissue. Solitary neurofibromas that are limited to the head and neck area are rare. It is a well-defined, benign, slowly growing tumor, attached to the nerve of origin, which is generally asymptomatic. A 23-year-old woman, with a 5-year history of neck masses, presented at the outpatient department. There were swallowing difficulty and intermittent dyspnea. On radiologic studies, huge mass occupying right side of the neck from the low-oropharynx to the superior mediastinum, extended into the contralateral side of the neck through the prevertebral space with displacement of the common carotid and vertebral artery and upper esophagus. Multiple surgical resection of the neck masses was performed through a low neck incision. Two relatively well circumscribed multinodular rubbery huge masses measuring 20x13x9 cm and 14x14x11 cm were revealed. Cut surface showed pinkish white dense collagenous tissue with yellowish myxoid areas. There was no evidence of recurrence for 9-year follow-ups.

Chronic encapsulated intracerebral haematoma in a patient with medically intractable epilepsy

A bstract A patient with a chronic encapsulated intracerebral haematoma presenting with medically intractable epilepsy isdescribed. A tough capsule containing an old haematoma was confirmed surgically, and consisted of dense collagenous tissue with rich neovascularization. The radiological features, aetiology and treatment of this rare occurrence are discussed.

Heterotopic neural tissue in the pharynx of a 7-week-old kitten

A 7-week-old male kitten had a pharyngeal mass (1 x 2 cm) causing displacement of the tongue. The surgically resected tissue was seen to be a moderately discrete subepithelial mass comprising islands of neuroglia and neurons separated by dense collagenous connective tissue. It is not known whether this mass retained any connection with the brain. Histochemical and immunohistochemical examination confirmed the presence of neurons and a pleocellular glial population, supporting a diagnosis of heterotopic neural tissue. The cat remained well 20 months after surgical treatment. Heterotopic neural tissue is well-recognized in man but has not been described in animals.

Calcifying Fibrous Pseudotumor of Pleura:A Report of Three Cases of a Newly Described Entity Involving the Pleura

A newly recognized distinctive fibrous soft tissue lesion called "calcifying fibrous pseudotumor" (CFPT) was recently described in the soft tissues of the extremities, trunk, scrotum, groin, neck, or axilla. To date, CFPT has not been described in the pleura. The authors reviewed the clinical, radiologic, and pathologic features of three cases. A 23-year old woman and 34-year old man who presented with chest pain, and a 28-year old woman without chest symptoms were found to have a pleural mass on chest radiographs. Computed tomography (CT) scans of each patient revealed pleural-based nodular masses with central areas of increased attenuation due to calcifications. Each lesions consisted of circumscribed, but unencapsulated masses of hyalinized collagenous fibrotic tissue interspersed with lymphoplasmacytic infiltrates and calcifications, many of which had psammomatous features. The lesions were limited to the pleura and did not involve the underlying lung parenchyma. Electron microscopy in one case showed fibroblasts scattered in dense collagenous tissue. Calcifying fibrous pseudotumor is distinct from other pleural lesions such as fibrous tumor of pleura, calcified granulomas, calcified pleural plaques, and chronic fibrous pleuritis as well as intrapulmonary lesions such as hyalinizing granuloma, inflammatory pseudotumor, and amyloid. As in the soft tissues, local excision appears adequate therapy for CFPT of the pleura. If these lesions behave in a similar fashion to CFPT of soft tissues, one might expect a low frequency of local recurrence.

Intestine Submucosa and Polypropylene Mesh for Abdominal Wall Repair in Dogs

Continuing investigations of abdominal body wall reconstruction materials suggest that unacceptable implant complications continue and that the ideal material has not yet been found. This pilot study compared xenogeneic (porcine) small intestine submucosa (SIS) with polypropylene mesh (PPM) for repair of created partial-thickness (six dogs) and full-thickness (six dogs) abdominal wall defects. Postoperative clinical evaluation of all dogs showed no evidence of implant failure. Dogs were euthanized at 1, 2, and 4 months after surgery. The SIS implants were completely replaced by host tissue at 4 months as determined by immunohistochemistry. The resultant repair was well-organized, smooth, dense collagenous connective tissue that was well incorporated into the adjacent fascia and skeletal muscle fiber bundles. In the full-thickness defect dogs, omentum covered a significantly larger portion of PPM (P= 0.001) and was more firmly attached to PPM (P= 0.0001) compared to SIS/connective tissue repair. We conclude that xenogeneic SIS can be used as an abdominal body wall repair material in the dog and warrants further investigations.

Collagen-encapsulated coagulation necrosis in cerebral infarcts: a pathological study.

Coagulation necrosis (CN)--a type of necrosis characterized by firm, eosinophilic parenchyma with recognizable cell outlines--is thought to be a result of rapid degeneration of tissue protein to a gel state and loss of water which prevents the necrotic tissue from undergoing autolysis and cellular digestion. In this study, we observed CN in cerebral infarcts of 11 of 150 consecutive autopsy cases of large cerebral infarction. Cerebral CN in patients who had survived for about 1 month had already started to be surrounded by newly formed vessels and type I collagen-positive tissue. In patients who had survived for more than 1 year, CN was deposited with calcium and cholesterin crystals and encapsulated by thick, dense collagenous tissue. Encapsulation, however, was not always complete, a finding that suggests that other factors, such as gel transformation at an early stage of CN and calcification at a later stage, are important for the persistence of CN in the infarct. The results of our study suggest that cerebral CN occurs more frequently than is generally believed.

Fine sensory innervation of the knee joint capsule by group III and group IV nerve fibers in the cat.

Afferent group III and IV nerve fibers of the knee joint markedly differ in their responsiveness to mechanical stimulation, which may be reflected in the structure and location of their terminals. Therefore, in sympathectomized cats, the fine afferent innervation of the knee joint capsule was studied via ultrastructural three-dimensional reconstructions over distances of up to 300 microns. Small peripheral nerves and "free" (noncorpuscular) sensory nerve endings were found in a superficial layer of the outer fibrous part of the capsule, in the patellar retinaculum, and in the outer and inner surface layers of the medial collateral and patellar ligaments. Group III nerve fibers showed a proximal myelinated portion inside the nerve, an intermediate portion that lacks a myelin sheath and is only surrounded by perineurium, and a distal portion outside of the perineurium that forms the sensory ending proper. Group IV fibers showed only two distinct portions, an intraperineurial (proximal) and an extraperineurial (distal) portion without any further morphological differences. Outside of the perineurium, a network formed by Schwann cells ("Schwann cell reticulum") provides a pathway for the distal portion of the sensory axons. No distinct subgroups of the sensory terminal fibers could be defined according to the configuration of the Schwann cells and the nerve fiber terminals. Sensory terminals were located adjacent to different structures such as venous and lymphatic vessels, fat cells, and collagenous fibers. Distinct parts of the same terminal nerve fiber were found in close contact to a vessel wall; others were surrounded by dense collagenous tissue. Close to sensory endings, mast cells and mast cell-like cells were frequently found, indicating a functional relationship.

Characterization and localization of a putative oxytocin receptor in the cervix of the oestrous ewe.

The purpose of the present study was to investigate the presence of high-affinity oxytocin-binding sites (putative oxytocin receptors) in the cervix of the non-pregnant ewe. [3H]Oxytocin binding to the peripheral layers of cervical tissue (comprising the serosal layer and the least dense collagenous and muscular layers) and the remaining dense collagenous cervical tissue were studied separately. [3H]Oxytocin-binding sites were detected in membrane fractions prepared from both of these regions, but binding to the peripheral cervix was variable and binding site concentrations were low, hence these were not characterized further. A high-affinity oxytocin-binding site, having a dissociation constant of 1.8 nmol/l, was characterized in the dense collagenous regions of the cervix of ewes killed during the oestrous period. Similar dissociation constants were determined for [Arg8]-vasopressin and the oxytocin-specific agonist [Thr4, Gly7]-oxytocin in competition studies. [3H]Oxytocin binding to peripheral cervical tissue and to the dense collagenous cervix was generally low or undetectable during the luteal phase, but increased in both tissues around the time of luteolysis. Although specific binding to both tissues was variable during the oestrous period, it was higher at this time than during the luteal phase. [3H]Oxytocin-binding site concentrations were also found to be higher within the inner dense collagenous cervix of oestrous ewes than of pregnant, ovariectomized or anoestrous animals.(ABSTRACT TRUNCATED AT 250 WORDS)

Cutaneous meningioma underlying congenital localized hypertrichosis

A 28-year-old man had a circumscribed hypertrichotic area on the left lumbar region since birth. A biopsy specimen showed numerous normal-appearing hair follicles and arrector pili muscles. In the subcutaneous layer a mass of dense collagenous connective tissue formed the background in which ill-defined foci of meningothelial cells in nests and pseudovascular spaces were seen. Collagenous structures (pseudopsammoma bodies), some of which showed calcification (psammoma bodies), were also seen. A diagnosis of cutaneous meningioma was made.

Partial replacement of mitral valve by homograft: An experimental study

Satisfactory long-term clinical results with heart valves have renewed the interest in the use of mitral homografts, despite the technical difficulties with their surgical implantation. This report describes the behavior and viability of the partial mitral homograft in the ortotopic position in a chronic sheep model (n = 25). The 20 surviving animals were studied hemodynamically and were anesthetized and electively put to death 3, 6, 9, and 12 months after the operation. All specimens had a normal mitral valve without signs of infection or thrombosis. Light, scanning, and transmission electron microscopy showed the presence of viable endothelial cells from the recipient covering the graft, signs of reendothelialization, and organized dense collagen tissue. The structural integrity was more evident in the fresh mitral homografts. This method may provide consider improvement in the viability of the mitral homograft, and it could be a valid alternative for repair of mitral valve localized pathology.

Anogenital “Sweat” Glands

A new variant of cutaneous glands is described that occurs in the anogenital region, with its highest concentration in the interlabial sulcus of the vulva. The glands are characterized by a wide coiled tube from which originate acini, diverticula, and short branches; a lining of a compact simple columnar epithelium with prominent cytoplasmic snouts protruding into the lumen; and a broad mantle of loose fibromyxoid to dense collagenous connective tissue. Occasionally, true lobuli are formed resembling those of mammary glands. A close relationship to eccrine glands was evidenced by intermediate variants and the occasional observation of typical eccrine segments in otherwise characteristic anogenital glands. The glands revealed periodic changes of epithelium and stroma. Their strict localization around the derivatives of the embryonic cloacal entrance suggests a possible role in sexual functions. Their characteristic histology links and explains a series of disorders of the anogenital region in women (including functional vulvar mammary glands after pregnancy, fibrocystic disease, fibroadenoma, hidradenoma papilliferum, and some cases of adenocarcinoma, including Paget's disease) and in men [including fibroadenoma or apocrine cystadenoma, and cases of Paget's disease].

Morphologic Aspects and Morphogenesis of Blood Cysts on Canine Cardiac Valves

We investigated retrospectively the morphologic aspects of blood cysts of the atrioventricular valve in eight Beagle dogs and clarified the morphogenesis of the lesions. Study of serial sections revealed that the cysts communicate with the blood vessels; however, they showed no connection with the valve surface. Immunohistochemically, the thin endothelium of the lesions showed positive staining for factor VIII-related antigen. Histologic studies of a variety of sizes of blood cysts revealed four basic stages of blood cyst formation: 1) initially, the involved blood vessel undergoes only a slight enlargement that is not grossly detectable; 2) next, the vessel becomes moderately or markedly dilated and contains a large number of erythrocytes. The changes of this stage are macroscopically detectable; and 3) then, blood flow is arrested partly in the cystic lesion, followed by degeneration and necrosis of the cyst. At this third stage, fibrous tissue or dense collagenous connective tissue is usually seen surrounding the cyst; 4) and finally, metaplastic bone is formed within the lesion. Colloidal carbon infusion into the valves of normal canine hearts revealed the presence of an extensive, dense arrangement of blood vessels in the septal leaflet of the tricuspid valve, which usually is the recognized site to develop blood cysts.

Small Intestinal Submucosa as a Small-Diameter Arterial Graft in the Dog

Autogenous saphenous vein, human umbilical vein, modified bovine collagen, Dacron, and PTFE have been used as small-diameter arterial grafts with moderate success. We tested autogenous small intestine submucosa as a small-diameter arterial graft in both a carotid and femoral artery (mean ID 4.3 mm) of 18 dogs (total of 36 grafts). All dogs received aspirin and warfarin sodium for the first 8 weeks after surgery. Graft patency was evaluated by Doppler ultrasound techniques and angiography. Two grafts ruptured and 5 grafts occluded by 21 days after surgery. One graft became occluded at 14 weeks. Fifteen dogs were sacrificed at periodic intervals until 48 weeks after surgery. Patent grafts had no evidence of infection, propagating thrombus, or intimal hyperplasia. Graft aneurysmal dilation occurred in 4 grafts (11%). The grafts were composed of a dense organized collagenous connective tissue with no evidence of endothelial cell growth on the smooth luminal surface. Three dogs are alive at 76 to 82 weeks after surgery. Overall, graft patency was 75%. Graft patency after cessation of anticoagulation therapy was 92.3% (12 of 13 grafts). We conclude that autogenous small intestinal submucosa can be used as a small-diameter arterial graft in the dog and is worthy of further investigation.