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PubMedDate not supplied

Effects of cimetidine and pentagastrin on surgical repair of gastric mucosa.

BACKGROUND/AIMS: The aim of this work is to evaluate the repair of mucosal epithelium at the critical time of the beginning of reepithelization of stomach wound. METHODOLOGY: Structural and ultrastructural evaluation of rat gastric mucosa repair was carried out with administration of placebo, cimetidine and pentagastrin in different groups of rats (Rattus norvegicus albinus) during the first 7 post-operative days. Following 48 hours of starvation and anesthesia by ethyl ether inhalation, the animals were submitted to laparotomy exposing the stomach. A fusiform gastric resection measuring 5 mm in length was performed in the fundus stomach wall. The surgical wound was sutured in 2 plans: muscular tunic and visceral serosa. The abdominal wall was also sutured in 2 plans: parietal serosa-abdominal musculature and skin. During 6 consecutive post-operative days, the placebo group rats received 1 ml of distilled water intragastrically; those of the cimetidine group 10 mg/kg of cimetidine; and, animals of the pentagastrin group, 250 micrograms/kg of pentagastrin by intraperitoneal injection. On the 7th post-operative day, rats were killed and fragments of the stomach wall containing transverse section of surgical wound were collected and processed for light microscopy and electron microscopies. RESULTS: At the beginning of gastric mucosal wound reepithelization cimetidine has better effect than that of pentagastrin. CONCLUSIONS: Comparative mucosal morphology showed that cimetidine tends to accelerate the beginning of reepithelization of granulation tissue while pentagastrin delays reepithelization due to alteration of protective mucus and a provoking increase of granulation tissue.

Animals↗
PubMed1989

Nd-YAG laser-induced endobronchial burn. Management and long-term follow-up.

Endobronchial fires are a rare complication of Nd-YAG laser photoresection. Short-term morbidity is secondary to sloughing mucosa and mucous plugging. Aggressive pulmonary hygiene, including frequent bronchoscopies and possibly a tracheostomy, may be required. The major long-term complication is obstruction of the airways from granulation tissue. Long-term follow-up is required to evaluate and treat clinically significant granulation tissue in the airways.

Aged↗
PubMed1981

Efficacy of ivermectin against cutaneous Draschia and Habronema infection (summer sores) in horses.

Thirty-one horses with naturally occurring summer sores were given a single IM injection of 0.2 mg of ivermectin (22,23-dihydroavermectin B1)/kg during the summer of 1980. Larvae of Draschia and/or Habronema spp were recovered from biopsy samples taken from 21 of 25 horses (84%) on the day of anthelmintic treatment. There was a marked clinical improvement in 26 horses (84%) 7 days after ivermectin was given. The typical summer sore was replaced by healthy pink granulation tissue at 7 days and this healed after 1 to 5 weeks. Biopsy samples were taken from 21 of these horses 1 to 6 weeks after treatment, and the samples in 18 horses (86%) were negative for larvae. Five of the 31 infected horses did not respond to a single dose and appeared to have become reinfected. Biopsy samples taken from 3 of these horses were positive for larvae 2 to 4 weeks after the 1st dose, but became negative and healed 1 to 2 weeks after a 2nd dose with ivermectin. Histopathologic examination of sections from lesions before anthelmintic treatment showed granulation tissue with marked eosinophilic infiltration, multiple eosinophilic abscesses, and transverse sections of nematodes. In sections examined after anthelmintic treatment, there were marked reduction in the number of eosinophils and absence of eosinophilic abscesses or nematodes, and the granulation tissue was more mature, as indicated by the appearance of dense fibrous connective tissue.

Animals↗
PubMed2004

[Study on human amniotic membrane loaded with marrow mesenchymal stem cells and epidermis cells in promoting healing of wound combined with radiation injury].

OBJECTIVE: To investigate the results of human amniotic membrane (HAM) which are loaded with marrow mesenchymal stem cells (MSCs) and epidermis cells in treating full-thickness skin defect combined with radiation injury. METHODS: Eight minipigs were used in this study. Three round full-thickness wounds (phi3.67cm), which combined with radiation injury, were created on the dorsum of each side close to the vertebral column in each animal. Among 48 wounds, 24 left side wounds were treated with HAM loaded with MSCs and epidermis cells as experimental group (group A), 16 right side wounds with simple HAM (HAM group, group B) and 8 right side wounds with oil gauze as control (group C). The granulation tissue, reepithelization and wound area were observed after 1,2 and 3 weeks. Immunohistochemistry was performed using vWF as a marker for blood vessels. Image analysis was employed to test new area of wound at different interval time and healing rate of wound. RESULTS: The healing time of group A was 6 to 7 days faster than that of group C and 5 to 6 days fister than that of group B. After 15-17 days of graft, there were significant differences in new area of wound and healing rate between group A and groups B, C (P < 0. 01). New epidermis fully covered whole wound surface in group A, and their granulation tissue, which contained a lot of vWF, fibroblasts, capillaries and collagen, grew well. Many inflammatory cells still were seen in groups B and C, and their contents of vWF, fibroblasts, capillaries and collagen in granulation tissue were smaller than that in group A. CONCLUSION: The graft of HAM loaded with MSCs and epidermis cells played an effective role in promoting healing of wound combined radiation injury with high quality.

Amnion↗
PubMed1992

Effects of bradykinin on the hemodynamics of tumor and granulating normal tissue microvasculature.

Bradykinin (BK) is an important endogenous mediator of microvascular flow modulation. Since the structure of the microcirculation is very different in tumor tissues than in normal tissues, bradykinin may elicit different responses in tumors. This study was designed to test the hypothesis that local administration of bradykinin increases blood flow preferentially in normal tissue relative to adjacent tumor tissue, resulting in a "vascular steal" phenomenon. Microvessel diameters (D), velocities (Vc), length densities, shear rates, and intermittent flow frequencies were measured every 10 min before, during, and after 40 min exposure to BK in rats with dorsal flap window chambers 9 days after tumor implantation. Separate studies were made of normal vessels outside the tumor margin, the hypervascular tumor periphery, and the tumor center. Bradykinin was administered with a suffusion medium flowing over the tissue at 1-2 ml/min with a BK concentration of 1.6 x 10(7) M. Administration of BK created five distinct changes in normal and tumor vessel function that varied over time, but coincidentally reached a maximum effect after 20 min exposure to BK. In normal vessels, increased Vc and D led to increased flow, which reached a peak 20 min after onset of suffusion with BK. In contrast, in centrally located tumor vessels, decreased D and Vc were observed in most vessels during the initial 10-20 min of suffusion. In addition, there was a significant increase in intermittent flow frequency in tumor central vessels, which peaked after 20 min of suffusion with BK. These five separate observations that coincided at 20 min of suffusion are consistent with a "vascular steal" phenomenon. The increase in normal microvessel D and Vc at 20 min suggests that BK causes vasodilation in arterioles. The coincident decrease in tumor microvessel D and Vc suggests that tumor feeding vessels are less able to respond to BK by vasodilating. The concomitant increase in intermittent flow frequency in tumor vessels suggests that a reduction in pressure drop occurred after 20 min exposure to BK, which is also consistent with "vascular steal." Since BK is also known to increase vascular permeability, it is possible that increases in interstitial fluid pressure brought on by exposure to BK contributed to the observed reduction in tumor blood flow. In normal vessels, reduced D and Vc, relative to peak values, were noted after 40 min suffusion with BK. Adherence of leukocytes to the vessel walls was prominent and microthrombi were also observed during this period. No evidence of such adhesion was seen in tumor vessels, although microthrombi were observed.(ABSTRACT TRUNCATED AT 400 WORDS)

Adenocarcinoma↗
PubMedDate not supplied

Effect of recombinant platelet-derived growth factor (Regranex) on wound closure in genetically diabetic mice.

Burns, especially those involving large surface areas, represent a complex wound healing problem. Platelet-derived growth factor (PDGF) is released by activated platelets to recruit inflammatory cells toward the wound bed. It has effects on promoting angiogenesis and granulation tissue formation. However, the effectiveness of topical PDGF on wound closure is variable, ranging from little improvement observed in pig models to dramatic improvement reported in a diabetic mouse model. Here, we sought to determine the effectiveness of commercially sold PDGF-BB (Regranex) on wound closure in genetically diabetic mice. C57BL/KsJ db+/db+ mice and its host strain bearing dorsal 1.5-cm wounds were divided into groups (n = 8 in each group) receiving topical application of either Regranex (10 microg/wound) or vehicle for 5 consecutive days after wounding. The rate of wound closure was analyzed using computerized planimetry. The amount of granulation tissue was determined histologically. Our data indicate that diabetic mice exhibit a significant delay in wound closure when compared with their host strain. Topical application of Regranex did not improve the time to wound closure but did significantly increase the amount of granulation tissue. Our current study using commercially available Regranex failed to reproduce the previously reported finding that PDGF improved wound closure in healing impaired genetically diabetic mice.

Administration, Topical↗
PubMed1998

Osseointegrated implants and orbital defects: U.C.L.A. experience.

PURPOSE: A clinical study of 23 craniofacial implants placed in 8 irradiated and nonirradiated orbital detects was conducted over a 7-year period. MATERIAL AND METHODS: Implant-retained orbital prostheses were fabricated, implant success rate was determined, and the soft tissue responses were recorded at 6-month intervals. As a result of patient death, no data were gathered on three implants. A five-point scale was used to record the health of the peri-implant soft tissues and the patients were followed from 9 to 72 months. The unit of measure was a visit/site that was assigned for each instance an implant site was evaluated. Evaluations were conducted at 6-month intervals, and for the study period, there were 80 visit/sites. RESULTS: The study revealed that 42.5% (34/80) of the visit/sites demonstrated an absence of inflammation; 23.7% (19/80) of visit/sites demonstrated slight redness; 13.8% (11/80) demonstrated peri-implant red and moist tissues; 6.2% (5/80) demonstrated granulation tissue associated with the implants; and 13.8% (11/80) infection of the peri-implant soft tissues was noted. Implant success rate was 35% (7/20); implant success rate in the nonradiated patients was 37.5% (3/8) and the success rate for radiated patients was 33.3% (4/12). Implants placed in the orbital region demonstrated a high failure rate. Most implant failures occurred late as opposed to early in the study period. CONCLUSION: Orbital implants should be placed in patients who understand that long-term success rates may be low and require meticulous hygiene maintenance.

Adult↗
PubMed2000

Hematogenous pyogenic spinal infections and their surgical management.

STUDY DESIGN: Mainly a retrospective study of 101 cases of pyogenic spinal infection, excluding postoperative infections. Data were obtained through medical record review, imaging examination, and patient follow-up evaluation. SUMMARY OF BACKGROUND DATA: Hematogenous pyogenic spinal infection has been described variously as spondylodiscitis, discitis, vertebral osteomyelitis, and epidural abscess. Recommended treatment options have included conservative methods (antibiotics and bracing) and surgical intervention. However, a comprehensive classification that would aid in diagnosis, treatment planning, and prognosis has not yet been devised. OBJECTIVES: To analyze the bacteriology, pathologic entities, complications, and results of treatment options for pyogenic spinal infection. METHOD: All patients received plain radiographs, gadolinium-enhanced magnetic resonance imaging scans, and bone/gallium radionuclide studies. All patients had tissue biopsies. Bacteriology, hematology, and predisposing factors were analyzed. All patients received intravenous and oral antibiotics. A total of 58 patients underwent surgery. Patient outcomes were correlated with clinical status, with treatment method and, where applicable, with location and nature of epidural compression. Statistical analyses were performed. RESULTS: Spondylodiscitis occurred most commonly with primary epidural abscess, spondylitis, discitis, and pyogenic facet arthropathy, all occurring rarely. Staphylococcus aureus was the main organism. Infection elsewhere was the most common predisposing factor. Leukocyte counts were elevated in 42.6% of spondylodiscitis cases. The erythrocyte sedimentation rate was elevated in all cases of epidural abscess. There were 35 cases of epidural abscess (frank abscess, 29; granulation tissue, 6). Epidural abscess complicating spondylodiscitis occurred most often in the cervical spine, followed by thoracic and lumbar areas. The rate of paraplegia or paraparesis also was highest in cervical and thoracic regions. There were no cases of quadriplegia. All patients with either epidural granulation tissue or paraparesis recovered completely after surgical decompression. Only 18% of patients with frank epidural abscess and 23% of patients with paralysis recovered completely after surgical decompression. Patients with spondylodiscitis who were treated nonsurgically reported residual back pain more often (64%) than patients treated surgically (26.3%). CONCLUSIONS: Pyogenic spinal infection can be thought of as a spectrum of disease comprising spondylitis, discitis, spondylodiscitis, pyogenic facet arthropathy, and epidural abscess. Spondylodiscitis is more prone to develop epidural abscesses in the cervical spine (90%) than the thoracic (33.3%) or lumbar (23.6%) areas. Thecal sac neurocompression has a greater chance of causing neurologic deficit in the thoracic spine (81.8%). Treatment of neurologic deficit caused by epidural abscess is prompt surgical decompression, with or without fusion. Patients with frank abscess had less favorable outcomes than those with granulation tissue, and paraplegia responded to treatment more poorly than paraparesis. Surgery was preferable to nonsurgical treatment for improving back pain.

Abscess↗
PubMed2004

Effect of acitretin on wound healing in organ transplant recipients.

BACKGROUND: Systemic retinoids possess significant benefits in cutaneous malignancy chemoprevention; however, retinoids have been associated with excessive granulation tissue and hypertrophic scarring. OBJECTIVE: The objective of this study was to assess wound healing outcomes in organ transplant recipients, both with and without the concomitant use of systemic acitretin chemoprophylaxis. METHODS: Twenty-nine immunosuppressed organ transplant recipients underwent treatment of basal cell or squamous cell carcinoma by Mohs or excisional surgery, with a total of 85 wounds. Wounds were evaluated postoperatively at early (average 12.9 days) and late (average 75.8 days) time points. Endpoints for all wounds included infection, hypertrophic granulation tissue, and hypertrophic scarring. Reconstructed wounds were also evaluated for dehiscence. RESULTS: Eleven patients taking oral acitretin had 41 wounds, of which 33 were reconstructed and 8 healed by second intention. The 18 patients not taking acitretin (control group) had a total of 44 wounds, of which 33 were reconstructed and 11 healed by second intention. There were no statistically significant differences between the acitretin group and the control group in the incidences of infection, dehiscence, hypertrophic granulation tissue, or hypertrophic scarring at early or late evaluation points. CONCLUSIONS: Systemic acitretin chemoprophylaxis does not appear to increase the risk of wound healing complications in organ transplant recipients.

Acitretin↗
PubMed2003

[Aural polyp in chronic inflammatory middle ear disease].

240 patients with chronic otitis media (COM) were studied: 166 ears termed as non cholesteatomatous otitis media and 74 with cholesteatoma. In 38 ears an aural polyp was found with no evidence of cholesteatoma in 19 ears (11.4%) whereas a cholesteatoma was present in the remaining 19 ears. The histology of the polyp and the characteristics of the chronic process were matched: a) The aural polyp is an infrequent complication in COM. b) After histological analysis was found to present two different pictures: The inflammatory reaction polyp, present in non cholesteatomatous COM; and the polyp with granulation tissue and foreign body reaction (keratina) usually found in cholesteatomatous COM. c) The finding of granulation tissue reaction and keratina in an aural polyp is a good predictor for the presence of a cholesteatoma.

Cholesteatoma, Middle Ear↗
PubMed1990

EGF increases short-term type I collagen accumulation during wound healing in diabetic rats.

Continuous topical application of epidermal growth factor (EGF) to granulation tissue increases the rate of collagen accumulation. It is believed that the clinical use of growth factors, such as EGF, may become common in the treatment of impaired wound healing in the near future. Impairments in the production and degradation of wound collagens have been demonstrated in diabetes mellitus. We studied the effects of a single, local application of EGF on collagen content, collagenase activity, and the ratio of type III and type I collagens within granulation tissue using polytetrafluoroethylene (PTFE) wound cylinders in 48 streptozotocin-induced diabetic rats in order to determine potential benefits of EGF to wound healing in diabetics. Wound collagen content in EGF-treated diabetic animals was significantly higher than in diabetic controls during the first 10 days of wound healing (236% on day 5, P less than .001; 140% on day 10, P less than .01), but decreased to significantly lower levels by day 15 of healing (71% of diabetic controls, P less than .01; 47% of nondiabetic controls, P less than .01). An 18% increase in diabetic wound protease activity was observed following application of EGF (P less than .001). The ratio of type III collagen to total wound collagen within the granulation tissue was significantly reduced (P less than .001) following EGF application. We demonstrate that a single, topical application of EGF promotes early synthesis of type I collagen, thereby deranging the usual type III/total collagen ratio, and is associated with increased wound protease activity.

Administration, Topical↗
PubMed1995

The origin of fibroblasts and their role in the early stages of horizontal furcation defect healing in the beagle dog.

The origin of fibroblasts, their proliferative activity and roles in the early stages of periodontal repair were investigated in order to better understand the periodontal healing process in furcation defects of the beagle dog after guided tissue regenerative therapy. Newly divided cells were identified by immunolocalization of bromodeoxyuridine (BrdU) injected 1 hour prior to sacrificing the animals. At 1 and 2 weeks after creation of the defects, the lesions were occupied primarily by granulation tissue. Under this condition, periodontal ligaments (PDL) fibroblasts in a coronal portion of the remaining PDL close to wounds proliferated actively, migrated along the root surface and formed fibrous connective tissue on the surface. Similarly, the fibroblasts adjacent to the bone surface also showed proliferative activity and engaged in active formation of fibrous connective tissue on the bone surface. The majority of labeled cells in both areas were located in the extravascular area. At 3 and 4 weeks, the defects were filled with an increased amount of new connective tissue and bone. The labeled fibroblasts were preferentially found in the most coronal portion of connective tissue formed on the root surface that was in direct contact with inflamed tissue, and the collagen fibers projected into granulation tissue. In areas of active bone formation, numerous labeled fibroblasts were located in connective tissue adjacent to the newly-formed bone. However, fibroblasts in the endosteum of new bone were rarely labeled These results indicate that fibroblasts involved in periodontal repair originate primarily from both the remaining PDL and alveolar bone, and actively engage in fibrous connective tissue formation in the early stages of periodontal repair The ability of PDL fibroblasts to proliferate, migrate, and form connective tissue on the root surfaces in the early repair stages appears to play a crucial role in the formation of the PDL and cementum, and consequently, in periodontal regeneration in the absence of root resorption and ankylosis. As the formation of new connective tissue and bone continues, the precursor cells for fibroblasts and osteoblasts are supplied locally through the continued divisions of the fibroblastic cells in association with the newly-formed connective tissue. Paravascular and endosteal cells appear to be minor contributors to new cell population during furcation defect repair in the beagle dog.

Alveolar Process↗
PubMed1991

Alterations in proteoglycan synthesis common to healing wounds and tumors.

Wound healing and tumor stroma generation share several important properties, including hyperpermeable blood vessels, extravasation of fibrinogen, and extravascular clotting. In both, the deposits of fibrin gel serve initially as provisional stroma and later are replaced by granulation tissue. Proteoglycans (PG) are also important constituents of the extracellular matrix, but their composition and role in healing wounds and tumor stroma generation are poorly understood. The authors used immunohistochemical and biochemical methods to investigate the dermatan sulfate proteoglycan (DSPG) and chondroitin sulfate proteoglycan (CSPG) composition of healing skin wounds and solid tumors. By immunohistochemistry, the great majority of normal guinea pig and human dermis stained weakly for CSPG and strongly for decorin. In contrast, the granulation tissue of healing skin wounds and scars stained intensely for CSPG and weakly or not at all for decorin; however decorin staining was restored to normal intensity after digestion with chondroitin ABC lyase, suggesting that decorin antigenic sites had been masked by glycosaminoglycan (GAG) chains. Like wounds, the stroma of several carcinomas (line 1 guinea pig, human breast, colon, basal cell, and squamous) stained strongly for CSPG and weakly or not at all for decorin, but decorin staining developed after chondroitin ABC lyase digestion. Thus healing wounds and tumor stroma express a common pattern of altered PG staining, adding another to the properties these pathologic entities share. Proteoglycans extracted from healing wounds after in situ labelling with [35S] Na sulfate contained more CSPG than normal dermis with significantly longer GAG chains. Granulation tissue also synthesized more DSPG than normal skin, with greater heterogeneity and longer GAG chains. These alterations in PG synthesis correlate with the cell proliferation, migration, and collagen synthesis that accompany wound healing and may provide clues to the mechanisms responsible for both wound healing and tumor stroma generation.

Animals↗
PubMed2002

The effect of basic fibroblast growth factor on scarring.

Granulation-tissue myofibroblasts are important in wound contraction, disappearing in normal scars but persisting in hypertrophic scars. While transforming growth factor beta 1 (TGF-beta 1) is implicated in excessive scarring and induces the accumulation of myofibroblasts, the role of basic fibroblast growth factor (FGF-2) on scarring remains unreported. Four linear full-thickness incisions, each 20 mm long, were made dorsally on 25 adult male Hooded Lister rats. In each animal, one wound was unmanipulated (control), one was injected with TGF-beta 1 (positive control), one with vehicle alone and one with FGF-2 (test). The wounds were injected daily for 5 days. Animals were sacrificed in groups of five on days 5, 10, 15, 20 and 30 after wounding. Wounds were subjected to tensiometry. Sections were stained for collagen fibres, immunostained for myofibroblasts and studied under light microscopy and electron microscopy. Myofibroblasts were present in the granulation tissue on day 5, reached their maximum number on day 10 and disappeared from all wounds by day 30. Treatment with FGF-2 inhibited this transient phenotypic change of granulation-tissue fibroblasts into myofibroblasts, relative to controls (15.23% versus 58.71%, 15.23% versus 54.71% and 15.23% versus 53.15%; P<0.003 on day 10, paired t-test). Test collagen-fibre orientation resembled that of the normal dermis, in contrast to that of the control wounds. Test wound breaking strength was unreduced. These results suggest a possible anti-scarring effect of FGF-2 during wound healing.

Animals↗
PubMed1990

Tears of the anulus fibrosus: assessment with Gd-DTPA-enhanced MR imaging.

T2-weighted images have been shown to be capable of defining anular tears in vitro as increased signal intensity within the normal low-signal-intensity anulus fibrosus. Since growth of granulation tissue into anular tears has been described as part of the healing process, it seemed likely that gadolinium-DTPA should enhance anular tears as it does scar tissue in other parts of the spine. We retrospectively reviewed spinal MR images from 30 previously unoperated patients and correlated areas of increased signal intensity within the anulus on T2-weighted images with areas of enhancement on T1-weighted images, and to a limited extent, with surgical findings. Eighteen separate areas of anular enhancement were found in 12 patients (six cervical, 12 lumbar). Only five of these enhancing areas showed increased signal intensity on T2-weighted images, four of a type II tear pattern and one of a type III tear pattern. Contrast enhancement within the anulus was in a pattern of type II tear in 14 and type III in four. Histology from an enhancing type II anulus demonstrated vascularized granulation tissue within the avascular anulus, without focal herniation. Anular tears may be imaged in vivo not only with T2-weighted images but also with gadolinium-DTPA-enhanced T1-weighted images by virtue of their vascularized granulation tissue.

Back Pain↗
PubMedDate not supplied

Tears of the anulus fibrosus: assessment with Gd-DTPA-enhanced MR imaging.

T2-weighted images have been shown to be capable of defining anular tears in vitro as increased signal intensity within the normal low-signal-intensity anulus fibrosus. Since growth of granulation tissue into anular tears has been described as part of the healing process, it seemed likely that gadolinium-DTPA should enhance anular tears as it does scar tissue in other parts of the spine. We retrospectively reviewed spinal MR images from 30 previously unoperated patients and correlated areas of increased signal intensity within the anulus on T2-weighted images with areas of enhancement on T1-weighted images, and to a limited extent, with surgical findings. Eighteen separate areas of anular enhancement were found in 12 patients (six cervical, 12 lumbar). Only five of these enhancing areas showed increased signal intensity on T2-weighted images, four of a type II tear pattern and one of a type III tear pattern. Contrast enhancement within the anulus was in a pattern of type II tear in 14 and type III in four. Histology from an enhancing type II anulus demonstrated vascularized granulation tissue within the avascular anulus, without focal herniation. Anular tears may be imaged in vivo not only with T2-weighted images but also with gadolinium-DTPA-enhanced T1-weighted images by virtue of their vascularized granulation tissue.

Contrast Media↗
PubMed2005

Influence of a dexamethasone-eluting covered stent on tissue reaction: an experimental study in a canine bronchial model.

This study was designed to evaluate the feasibility and efficacy of a dexamethasone (DXM)-eluting, covered, self-expanding metallic stent to reduce tissue reaction following stent placement in a canine bronchial model. We placed a DXM-eluting, polyurethane-covered, self-expanding metallic stent (drug stent, DS) and a polyurethane-covered, self-expanding metallic stent (control stent, CS) alternately in each left main bronchus and left lower lobe bronchus in 12 dogs. The stents were 20 mm in diameter and length when fully expanded. The dose of DXM was approximately 36.7 mg in each DS, but was absent in the CS. The dogs were euthanased 1 week (n=4), 2 weeks (n=4) or 4 weeks (n=4) after stent placement. Histologic findings, such as epithelial erosion/ulcer or granulation tissue thickness, were obtained from the mid-portion of the bronchus, where the stent had been placed, and evaluated between DS and CS. There were no procedure-related complications or malpositioning of any of the bronchial stents. Stent migration was detected in one dog just before euthanasia 1 week following stent placement. Stent patency was maintained until euthanasia in all dogs. Epithelial erosion/ulcer (%) was significantly less in the DS (mean+/-standard deviation, 46.88+/-23.75) than in the CS (73.75+/-14.08) (P=0.026) for all time-points. There was a decrease in epithelial erosion/ulcer as the follow-up period increased in both DS and CS. The granulation tissue thickness (mm) was less in DS (2.63+/-2.05) than in CS (3.49+/-2.95), although the difference was not significant (P=0.751) for all time-points. There was a tendency toward an increase in granulation tissue thickness and chronic lymphocytic infiltration as the follow-up period increased in both DS and CS. In conclusion, DXM-eluting, covered, self-expanding metallic stent seems to be effective in reducing tissue reaction secondary to stent placement in a canine bronchial model.

Animals↗
PubMed1996

A new aneurysm wrapping material: polyglactin 910 + fibrin sealant.

Aneurysms experimentally induced by using the silver nitrate coagulation method in 10 Wistar Albino rats are wrapped with Polyglactin 910 and Fibrin Sealant. 6 weeks later the rats are sacrificed and compared with the control group. In the group in which Polyglactin 910 and Fibrin Sealant were used as the wrapping material, non-specific inflammatory granulation tissue development around the aneurysms is observed. We suggest that a Polyglactin 910 and Fibrin Sealant combination can be used as a wrapping material in the treatment of aneurysms where clipping is not possible.

Animals↗