Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Granulation Tissue”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 253 records · Page 14Linked to original sources
PubMed1975

Inhibition of granulation tissue growth by histamine.

Granulomas were induced in rats by subcutaneous implantation of formalin-soaked filter-paper disks. Daily subcutaneous injection of histamine at doses of two times 0.05 mg/kg and above inhibited the growth of granulation tissue as measured by a marked decrease in the dry-defatted granuloma weight and of the hydroxyproline and hexosamine content. Histological observations of granulation tissue indicated that histamine inhibited the proliferation of fibroblasts and the formation of capillaries. Inhibitory effects were also observed with the histamine releaser, sinomenine, and the histaminase inhibitor, aminoguanidine. These histamine effects seem not to be mediated by glucocorticoid release, since an effective dose level of histamine produced no change in growth or thymus weight. Prednisolone was less potent than histamine in inhibiting Prednisolone was ineffective at the dose tested. Subcutaneous injection of the H2-receptor antagonist, burimamide, blocked these histamine effects and also of sinomeinine and aminoguanidine. The H1-receptor antagonist, mepyramine, did not block these histamine effects. Burimamide alone enhanced the growth of granuloma. These results indicate that granulation-tissue growth in inflammation is affected by the inhibitory effect of endogenous histamine acting through H2-receptors.

Amine Oxidase (Copper-Containing)↗
PubMed1994

[A case of an intracerebral mass lesion consisting of traumatic granulation tissue].

We reported a rare case of an intracerebral granulomatous lesion accompanying severe edema formation in the healing stage of traumatic brain contusions. A 44-year-old male patient came to our outpatient clinic due to progressing headache and nausea. Upon computed tomographic examination, a low density mass with strong surrounding edema was detected at the right frontal base. Magnetic resonance images revealed a high intensity mass on both T1- and T2-weighted images at the right frontal base. Upon intravenous injection of a contrast agent, this lesion exhibited multifocal marginal contrast enhancement. Two additional small enhanced mass lesions were detected at the tip of the right temporal lobe and the medial portion of the left temporal lobe. We tentatively diagnosed it as a right frontal brain tumor and attempted the total removal of the right frontal mass. Unexpectedly, pathological diagnosis was intracerebral granulation tissue associated with accumulation of hemosiderin-laden macrophages and capillary wall thickening. In addition, there was no reactive gliosis. We speculated on the pathogenesis of intracerebral granulation tissue as follows. Since the patient was a heavy drinker and often fell down when he was drunk, it is likely that he might be suffering from intracerebral hematomas due to traumatic contusions. This assumption may be supported by the fact that an old subdural hematoma was observed during the operation and the radiological examination revealed multiple lesions. The gathering and proliferation of mesenchymal cells possibly derived from blood circulation probably began at the site of the damaged brain tissue, thus forming intracerebral granulation tissue.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1982

Fibronectin involvement in granulation tissue and wound healing in rabbits.

This study describes the distribution of fibronectin and its association with reticulin fibers (type III collagen) and hyaluronic acid in shallow rabbit wounds. Linear incisions were made dorsally with a surgical blade. Animals were sacrificed and 1,2,3,4,5, and 8 day wounds were examined using peroxidase-antiperoxidase to localize affinity-purified antibodies to fibronectin. Tissue samples were also stained with hematoxylin and eosin in addition to silver stains for reticulin, and Alcian blue for hyaluronic acid. After wounding, the incision filled with a fibrin clot that stained positively for fibronectin. The underlying dermis and adjacent, unwounded dermis also contained fibronectin. Epidermal cells that migrate from the wound margin between the clot and the dermis were in direct association with fibronectin in these wound components. By 72 hr, epidermal continuity was reestablished. Early granulation tissue formation was apparent just below the epidermis 5 day wounds. Fibronectin was observed in the matrix surrounding individual fibroblasts and codistributed with reticulin fibers and hyaluronic acid in both 5 and 8 day wounds. Granulation tissue of 8 day wounds stained intensely for fibronectin and extended to a greater depth in the reticular dermis. Dense fibrillar networks of fibronectin and fibroblasts were aligned parallel to the epidermis, giving the granulation tissue a highly structured and organized appearance. Fibroblasts contained fibronectin and were surrounded by less fibronectin at the wound periphery than within the granulation tissue. These findings suggest that fibronectin may be important in the reconstruction of tissues during repair by functioning as an extracellular scaffold for migrating cells.

Animals↗
PubMedDate not supplied

Contraction of myofibroblasts in granulation tissue is dependent on Rho/Rho kinase/myosin light chain phosphatase activity.

During wound healing and fibrocontractive diseases fibroblasts acquire a smooth muscle cell-like phenotype by differentiating into contractile force generating myofibroblasts. We examined whether regulation of myofibroblast contraction in granulation tissue is dominated by Ca2+-induced phosphorylation of myosin light chain kinase or by Rho/Rho kinase (ROCK)-mediated inhibition of myosin light chain phosphatase, similar to that of cultured myofibroblasts. Strips of granulation tissue obtained from rat granuloma pouches were stimulated with endothelin-1 (ET-1), serotonin, and angiotensin-II and isometric force generation was measured. We here investigated ET-1 in depth, because it was the only agonist that produced a long-lasting and strong response. The ROCK inhibitor Y27632 completely inhibited ET-1-promoted contraction and the phosphatase inhibitor calyculin elicited contraction in the absence of any other agonists, suggesting that activation of the Rho/ROCK/myosn light chain phosphatase pathway is critical in regulating in vivo myofibroblast contraction. Membrane depolarization with K+ also stimulated a long-lasting contraction of granulation tissue; however, the amount of force generated was significantly less compared to ET-1. Moreover, K+-induced contraction was inhibited by Y27632. These results are consistent with inhibition of myosin light chain phosphatase by the Rho/ROCK signaling pathway, which would account for the long-duration contraction of myofibroblasts necessary for wound closure.

Amides↗
PubMed1989

Differentiation of T lymphocyte subpopulations, macrophages, and HLA-DR-restricted cells of apical granulation tissue.

Sixteen specimens excised from apical granulation tissue were examined for immunocompetent T lymphocytes, mononuclear phagocytes, and HLA-DR-determined cells. Light microscopic visualization of the cells was performed using monoclonal antibodies and the immunocytochemical alkaline phosphatase anti-alkaline phosphatase technique. Quantitative assessment of the biopsy specimens showed that in five diagnosed cysts, eight granulomas, and three specimens taken from scar tissue, macrophages represented the dominating inflammatory cell fraction, followed by T lymphocytes. In the latter group, helper/inducer T cells were most frequent. Cysts showed a statistically significant increase in cell populations of helper/inducer, suppressor/cytotoxic T cells, macrophages, and HLA-DR-coded cells. There were only a few activated T lymphocytes.

HLA-DR Antigens↗
PubMed1975

Effect of hyperbarism on collagenous protein metabolism in granulation tissue.

Rats with subcutaneously implanted polyurethane sponges were exposed 6 hours daily for 7 days to high ambient atmospheric pressures (1.5, 2, 2.5 and 3 ATA). Another group was exposed 4 hours daily for 4 weeks to 3 ATA before inducing granulation tissue formation. 14C-proline was administered 16 hours before terminating the experiment. Free hydroxyproline, soluble and insoluble collagen and total noncollagenous protein were isolated from the 7-day granuloma and the amount and radioactivity of 14C-hydroxyproline and 14C-proline were determined. Seven days' graduated hyperbarism did not affect collagen synthesis; the maturation of collagen to insoluble forms was inhibited at 2 and 2.5 ATA, but not at 3 ATA. Stimulated degradation of collagen (free hydroxyproline) was observed at 2, 2.5 and 3 ATA. In animals subjected to long-term exposure at 3 ATA pressure, the collagen in the granuloma matured to insoluble forms more quickly. Biochemical changes were correlated with changes in the fine structure of the granulation tissue. The appearance of the fibroblast proteosynthetic apparatus was not influenced by hyperbarism. Progressive spherical transformation, fusion of mitochondria and lysosomal activation in the pericapillary fibroblasts occurred at 2, 2.5 and 3 ATA. In short-term experiment, the formation of cytosegresomes and cellular necrosis also contributed to the effect at 3 ATA, which is thus already a toxic pressure for granulation tissue.

Animals↗
PubMed1988

Collagen type IV and procollagen type III during granulation tissue formation: a serological, biochemical, immunohistochemical and morphometrical study on the viscose cellulose sponge rat model.

The serum concentrations of collagen type IV,7S, collagen type IV,nc1, and aminoterminal type III procollagen peptide immunoreactive components were measured by means of specific radioimmunoassays during development of granulation tissue in rats. The results were compared with tissue deposition of basement membranes and interstitial collagens in the granulation as measured morphometrically. A parallel sequential pattern in tissue deposition of collagen types III and IV, and serum increase of collagen types III- and IV-related fragments, was observed. Serum collagen type IV was less sensitive as a marker for development of granulation tissue than the serum procollagen type III N-peptide. This was in accordance with a low collagen type IV/interstitial collagen ratio in the granulation tissue. However, a cross-sectional study showed that serum collagens types IV,7S and IV,nc1 may be useful as early quantitative indicators of granulation tissue formation. Simultaneously, measurement of collagen type IV- and procollagen type III N-peptide-related antigens in serum provides a differentiated reflection of the dynamic matrix processes in developing granulation tissue.

Animals↗
PubMed1993

Basal cell carcinoma arising in venous ulcers and mimicking granulation tissue.

BACKGROUND: Basal cell carcinoma (BCC) arising in venous ulcers is rare, and its appearance in this setting is not fully recognized. OBJECTIVE: The purpose of this report is to alert the clinician to the subtle clinical appearance of this tumor and to prompt a more rapid recognition. METHODS: We report five cases of BCC arising in venous ulcers of the lower extremity that we have observed over a period of 6 years. In all cases the tumor was diagnosed histologically. RESULTS: In all five cases the tumor had the appearance of seemingly healthy granulation tissue, which was often exuberant and translucent. The border of this apparent "granulation tissue" was rolled over the margins of the ulcer. CONCLUSION: Basal cell carcinoma arising in venous ulcers often has the appearance of translucent granulation tissue that extends beyond the ulcer's margins. These clinical characteristics should alert the clinician to the need for obtaining a biopsy of the ulcer bed.

Aged↗
PubMed1988

The influence of biosynthetic human growth hormone on biomechanical properties and collagen formation in granulation tissue.

Biomechanical properties and collagen formation in the granulation tissue of cellulose sponges, implanted subcutaneously in male rats for 7, 10 and 16 days, were tested after treatment with biosynthetic human growth hormone given subcutaneously in a dose of 0.5 mg/kg body weight/day. At each implantation period, one group started hormone treatment at the day of implantation and another group started hormone treatment 7 days prior to implantation. After 7 days of implantation, increases in maximum stress (36 per cent), relative failure energy (48 per cent) and strain at maximum stress (25 per cent) were found when treatment was started 7 days prior to implantation. After 10 days of implantation an increase in relative failure energy (60 per cent) was found when treatment was started 7 days prior to implantation. No differences were found after 7 and 10 days of implantation when treatment was started at the day of implantation. After 16 days of implantation, no influence on mechanical strength was found in any of the hormone treated groups. The collagen deposition after 7, 10 and 16 days did not differ in any of the hormone treated groups compared to controls.

Animals↗
PubMed1997

Significance of granulation tissue in torn supraspinatus insertions: an immunohistochemical study with antibodies against interleukin-1 beta, cathepsin D, and matrix metalloprotease-1.

The pathophysiology of rotator cuff tears can be elucidated by examining the tendinous insertion of the supraspinatus muscle. As seen by light microscopy, the granulation tissue around the insertion of a torn supraspinatus tendon appears to induce osteochondral destruction by means of multinucleated giant cells and chemical mediators. The purpose of this study was to examine the contribution of certain chemical mediators to osteochondral destruction using immunohistochemical analysis of interleukin-beta, cathepsin D, and matrix metalloprotease-1. Sixteen supraspinatus insertions with portions of the greater tuberosity, including eight complete-thickness tears and eight incomplete-thickness tears, were obtained during surgery. Six fresh cadaveric supraspinatus tendons without grossly evident tears served as normal controls. Strong immunoreactivity was found in all 16 torn supraspinatus insertions but not in the six insertions of apparently intact tendons. Macrophages and multinucleated giant cells, which showed immunoreactivity for all three chemical mediators, were often found at the interface between the osteochondral margin of the enthesis and the granulation tissue, suggesting that they may be involved in osteochondral destruction. We therefore concluded that, in addition to repetitive subacromial impingement, this granulation tissue may contribute to the development of rotator cuff tears by weakening the insertion.

Adult↗
PubMed1991

Lysyl oxidase-mediated crosslinking in granulation tissue collagen in two models of hyperglycemia.

Enzymatically mediated crosslinks and nonenzymatic glycation were quantified in granulation tissue collagen in two models of hyperglycemia, diabetes and galactosemia, that have opposite effects on collagen solubility. The effects of castration, which alters collagen solubility, was also investigated. Collagen from both diabetic and galactosemic rats had significantly increased levels of dihydroxylysinonorleucine (DHLNL), a difunctional reducible crosslink. Galactosemic rats had significantly decreased levels of hydroxypyridinium, a trifunctional product of DHLNL and hydroxylysine, relative to control values, while diabetic rats had normal levels. Values for all other detectable crosslinks in collagen from hyperglycemic rats were indistinguishable from control values. Nonenzymatic glycation was increased in both groups of hyperglycemic rats. In diabetic rats, but not in galactosemic rats, nonenzymatic glycation was strongly correlated with DHLNL content. Castration had no effect on crosslink content of collagen from diabetic or galactosemic rats. This study demonstrates that (1) collagen crosslinking is abnormal in granulation tissue collagen in both experimental diabetes and galactosemia, (2) these changes are similar to those observed in skin collagen from insulin-dependent diabetic subjects and (3) the crosslinking abnormalities are not correlated with alterations in collagen solubility. We conclude that hyperglycemia-associated increases in immature crosslinks cannot account for altered collagen solubility, although impaired maturation of such crosslinks may be partially responsible for the lathyrogenic effect of galactosemia.

Acetates↗
PubMed1975

[Current data on the functional morphology of granulation tissue cells in skin wounds].

The article summarizes the latest literature data on the morphology of the granulation tissue cells: neutrophils, monocytes, macrophages, mast cells and fibroblasts. In the majority of cases these cells were studied with the help of such methods as electron microscopy, histochemical analysis autoradiography. Sources of origin of these cells and dynamics of their development in the period of formation and maturation of the granulation tissue are considered. Findings of the current studies into the structure and functions of fibroblasts and their role in collagen formation, as well as the role of hormonal factors in these processes are analysed in detail.

Fibroblasts↗
PubMed2005

Intracellular formation of collagen microfibrils in granulation tissue.

It is important to determine the biosynthesis process of collagen fibers to elucidate the mechanism by which granulation tissue is induced after injury. The purpose of this study is to investigate whether collagen microfibrils can be formed not only outside but also inside a cell. Fibroblast-like cells in granulation tissue resulting from incision and ligation were examined. The cells possessed vesicles containing collagen microfibrils. The vesicles were present in connection with Golgi apparatus or the rough endoplasmic reticulum. Furthermore, the vesicles were exhibited to be secretory granules with the secretory granule marker Rab3A. The fibroblast-like cells were also indicated to be myofibroblasts, using conventional transmission electron microscopy and immunoelectron microscopy for the myofibroblast marker alpha smooth muscle actin. In conclusion, it was demonstrated that collagen microfibrils could be formed in the cell in the case of collagen fiber overproduction.

Actins↗
PubMed1980

Wound healing and formation of granulation tissue in normal and defibrinogenated rabbits. An experimental model and histological study.

The aim of this investigation was to develop an experimental model for studies on the significance of fibrin deposition for wound healing. Systemic defirbinogenation with Arvin was used to achieve abnormal fibrin deposition in subcutaneously implanted cellulose sponges. The formation of granulation tissue in the sponges was studied histologically. Arvin injections resulted in a rapid decrease in plasma fibrinogen concentration with a concomittant rise in fibrin-degradation products. No change in FXIIIa activity was seen. During defibrinogenation an abnormal fibrin deposition was found in the sponges. The fibrin strands appeared irregular and disrupted. The number of fibroblasts and collagen fibrils was reduced in granulation tissue formed during defibrinogenation. The model used seems to allow controlled studies on the significance of fibrin deposition for wound healing. Defibrinogenation was found to influence granulation tissue formation.

Animals↗
PubMed1991

Laryngeal and ocular granulation tissue formation in two Punjabi children: LOGIC syndrome.

Two unrelated children, both born in the United Kingdom of Punjabi Muslim parents, developed within months of birth, nodules in the larynx, conjunctiva and nailbeds. Currently the younger female child, aged five, is developing skin papules while the elder boy, now aged 15, is debilitated by oral, oesophageal and tracheal granulation tissue formation. Numerous biopsies of the affected tissues have revealed subepithelial granulation tissue formation of unknown aetiology. Extensive haematological, biochemical and bacteriological investigations were uninformative as to the cause. Treatment with steroids, dapsone, antituberculous drugs, and local excision failed to control the disease. No description of this condition exists in the international medical literature available to us.

Conjunctival Diseases↗
PubMed1985

The effect of inhibition of angiogenesis in granulation tissue on wound healing and the fibroblast.

Protamine sulfate given in high doses can inhibit angiogenesis in the granulation tissue generated in an open wound. This is reflected by changes consistent with delayed vascular maturation in the morphology of the regenerating vessels seen at the gross, microscopic, and ultrastructural levels. A coincidental delay in wound healing as evidenced by impaired wound contraction occurs, although fibroblast duplication and myofibroblast differentiation appear intact. However, the fibroblasts contain little endoplasmic reticulum, the site of synthetic activity, and the surrounding collagen appears loose and disorganized. To unite these observations into a coherent pattern, we review the proposal that the endothelial cell, the fibroblast, and the extracellular stroma are interdependent and that maturation of each is necessary to maintain the momentum of wound healing. Our findings fit this mechanistic hypothesis but do not prove it. The abnormal vasoformation that may be initiated by protamine's anticoagulant properties could set the stage for impaired fibroblast synthetic activity. If collagenous stroma is deficient, both endothelial maturation and wound contraction wound fail. Although we saw these final events, to prove a series of cause and effect changes would require further study of the oxygen tension and the fibrin and collagen levels in granulation tissue.

Animals↗
PubMed1975

Histological studies on granulation tissue from bipedicle tube flaps.

Histological studies were performed on granulation tissue from cylinders implanted 2 to 8 weeks and 4 months in bipedicle tube flaps on rabbits. Tissue from cylinders implanted in skin folds were used as controls. Flap and control tissue showed similar changes over the weeks. At weeks 2 and 3 the tissue was rich in cells, blood vessels and collagenous fibres. At week 4 the tissue showed transitional changes to week 5, when there were zones of loosely textured tissue with fine, fragmented collagen fibres. At week 5 some of the loose tissue was replaced by fat. Macrophages and inflammatory cells had appeared. By week 7 the fatty and collagenous tissue was mature and macrophages and inflammatory cells had disappeared.

Adipose Tissue↗