966 resultados para Epidermal wound healing
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We have investigated molecular mechanisms of the embryonic development of an ascidian, a primitive chordate which shares features of both invertebrates and vertebrates, with a view to identifying genes involved in development and metamorphosis, We isolated 12 partial cDNA sequences which were expressed in a stage-specific manner using differential display, We report here the isolation of a full-length cDNA sequence for one of these genes which was specifically expressed during the tailbud and larval stages of ascidian development, This cDNA, 1213 bp in length, is predicted to encode a protein of 337 amino acids containing four epidermal growth factor (EGF)-like repeats and three novel cysteine-rich repeats, Characterization of its spatial expression pattern by in situ hybridisation in late tailbud and larval embryos demonstrated strong expression localised throughout the papillae and anteriormost trunk and weaker expression in the epidermis of the remainder of the embryo, As recent evidence indicates that the signal for metamorphosis originates in the anterior trunk region, these results suggest that this gene may have a role in signalling the initiation of metamorphosis. (C) 1997 Wiley-Liss, Inc.
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We have observed in previous studies that 6-hydroxydopamine (6-OHDA)-induced lesions in the nigrostriatal dopamine (DA) system promote increases of the astroglial basic fibroblast growth factor (FGF-2, bFGF) synthesis in the ascending DA pathways, event that could be modified by adrenosteroid hormones. Here, we first evaluated the changes of microglial reactivity in relation to the FGF-2-mediated trophic responses in the lesioned nigrostriatal DA system. 6-OHDA was injected into the left side of the rat substantia nigra. The OX42 immunohistochemistry combined with stereology showed the time course of the microglial activation. The OX42 immunoreactivity (IR) was already increased in the pars compacta of the substantia nigra (SNc) and ventral tegmental area (VTA) 2 h after the 6-OHDA injection, peaked on day 7, and remained increased on the 14th day time-interval. In the neostriatum, OX42 immunoreactive (ir) microglial profiles increased at 24 h, peaked at 72 h, was still increased at 7 days but not 14 days after the 6-OHDA injection. Two-colour immunofluorescence analysis of the tyrosine hydroxylase (TH) and OX42 IRs revealed the presence of small patches of TH IR within the activated microglia. A decreased FGF-2 IR was seen in the cytoplasm of DA neurons of the SNc and VTA as soon as 2 h after 6-OHDA injection. The majority of the DA FGF-2 ir cells of these regions had disappeared 72 h after neurotoxin. The astroglial FGF-2 IR increased in the SNc and VTA, which peaked on day 7. Two-colour immunofluorescence and immunoperoxidase analyses of the FGF-2 and OX42 IRs revealed no FGF-2 IR within the reactive or resting microglia. Second, we have evaluated in a series of biochemical experiments whether adrenocortical manipulation can interfere with the nigral lesion and the state of local astroglial reaction, looking at the TH and GFAP levels respectively. Rats were adrenalectomized (ADX) and received a nigral 6-OHDA stereotaxical injection 2 days later and sacrificed up to 3 weeks after the DA lesion. Western blot analysis showed time-dependent decrease and elevation of TH and GFAP levels, respectively, in the lesioned versus contralateral midbrain sides, events potentiated by ADX and worsened by corticosterone replacement. ADX decreased the levels of FGF-2 protein (23 kDa isoform) in the lesioned side of the ventral midbrain compared contralaterally. The results indicate that reactive astroglia, but not reactive microglia, showed an increased FGF-2 IR in the process of DA cell degeneration induced by 6-OHDA. However, interactions between these glial cells may be relevant to the mechanisms which trigger the increased astroglial FGF-2 synthesis and thus may be related to the trophic state of DA neurons and the repair processes following DA lesion. The findings also gave further evidence that adrenocortical hormones may regulate astroglial-mediated trophic mechanisms and wound repair events in the lesioned DA system that may be relevant to the progression of Parkinson`s disease.
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PURPOSE: To compare corneal reepithelialization, pain scores, ocular discomfort, and tear production after photorefractive keratectomy (PRK) and butterfly laser epithelial keratomileusis (LASEK). METHODS: This prospective, randomized, double-masked study comprised 102 eyes of 51 patients who underwent laser refractive surgery. Each patient was randomized to have one eye operated on with PRK and the other with butterfly LASEK. Patients were followed for 1 year. RESULTS: The mean reepithelialization time in the PRK group was 4.35 +/- 0.48 days (range: 4 to 5 days) and 4.75 +/- 0.72 days (range: 4 to 6 days) in the butterfly LASEK group (P<.002). Pain scores and ocular discomfort were not statistically different between groups, although a trend towards a lower pain level with PRK was noted (3.31 +/- 4.09 vs 4.43 +/- 4.27; P=.18). Schirmer test values were significantly reduced from preoperative levels through 12 months with both PRK (23.6 +/- 8.1 vs 19.4 +/- 10.1; P<.002) and butterfly LASEK (22.4 +/- 8.7 vs 18.9 +/- 9.7; P=.01); however, no difference between groups was noted at any time. CONCLUSIONS: Photorefractive keratectomy showed a modest but statistically significant shorter reepithelialization time and a tendency towards lower pain scores than butterfly LASEK. The reepithelialization time was strongly associated with the duration of surgery in both techniques. A similar reduction of Schirmer test values was observed up to 1 year postoperatively in both groups.
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Mast cells (MCs) are associated with chronic inflammatory diseases. However, there is no study evaluating the importance of MCs in the mucosal leishmaniasis (ML). The aim of this study was to quantify the most important cytokines associated with mucosal leishmaniasis, before and after disease treatment, correlating with the healing. A cohort of 12 patients with ML was evaluated, and biopsies were taken before and after the treatment. A quantitative estimation of MCs and some cytokines was analysed by density of the labelled cells through immunohistochemistry. The MCs count in the tissue from patients with ML before treatment showed a mean of 29.3 +/- 37.9 cells/mm(2). The MCs count in patients with ML after healing decreased to 14.8 +/- 23.9 cells/mm(2). There was an inverse relation of MCs with IFN-gamma and IL-4 expression (r(2) = 29.4 and r(2) = 22.3 with P < 0.05). The expression of IL-10 and TNF-alpha was not related with MCs count. MCs decrease after treatment associated with decrease of IL-4 and IFN-gamma. The explanations of cytokine correlation are discussed in the article.
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Background: Through an experimental biomechanical study on rabbits, tendon reinsertion by means of trans-osseous suture on a spongy bone bed and suture anchor were evaluated comparatively at different phases of healing. Methods: Twenty-four New Zealand White rabbits were used: 2 as pilots, 4 as the control group, and 18 as the experimental group. These 18 animals underwent sectioning and reinsertion of the Achilles tendon bilaterally, using the technique of trans-osseous suture on 1 side and suture anchor on the other. All the pelvic limbs that underwent the procedure were then immobilized for 3 weeks. The experimental group was divided into 3 groups that were sacrificed, respectively, 3, 6, and 12 weeks later. The tendon-bone complex was subjected to biomechanical tests to evaluate the parameters of maximum strength, stiffness, and yield strength. Results: There was no statistically significant difference between the suture anchor group and the trans-osseous suture group, in relation to yield strength (3 weeks, P = .222; 6 weeks, P = .465; and 12 weeks, P = .200) or maximum strength (3 weeks, P = .222; 6 weeks, P = .076; and 12 weeks, P = .078). In relation to stiffness, the suture anchor group showed a statistically significant difference only at 3 weeks of healing ( P = .032) over the trans-osseous suture group. Conclusion: The technique of suturing with an anchor was shown to be similar to the technique of trans-osseous suture for the studied parameters. Level of evidence: Basic Science Study, In-Vitro Biomechanics Study. (C) 2010 Journal of Shoulder and Elbow Surgery Board of Trustees.
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Objective: We tested the hypothesis that combined 660 and 890 nm LED phototherapy will promote healing of diabetic ulcers that failed to respond to other forms of treatment. Research Design and Methods: A double-blind randomized placebo controlled design was used to study 23 diabetic leg ulcers in two groups of 14 patients. Group one ulcers were cleaned, dressed with 1% silver sulfadiazine cream and treated with ""placebo"" phototherapy (<1.0 J cm(-2)) twice per week, using a Dynatron Solaris 705 (R) device. Group two ulcers were treated similarly but received 3 J cm(-2) dose. Results: At each of 15,30,45,60,75, and 90 days of healing, mean ulcer granulation and healing rates were significantly higher for group two than the ""placebo"" group (P < 0.02). While ""placebo"" treated ulcers worsened during the initial 30 days, group two ulcers healed rapidly; achieving 56% more granulation and 79.2% faster healing by day 30, and maintaining similarly higher rates of granulation and healing over the ""placebo"" group all through. By day 90, 58.3% of group two ulcers had healed fully and 75% had achieved 90-100% healing. In contrast, only one ""placebo"" treated ulcer healed fully by day 90; no other ulcer attained >90% healing. Conclusion: Combined 660 and 890 nm light promotes rapid granulation and healing of diabetic ulcers that failed to respond to other forms of treatment. Lasers Surg. Med. 41:433-441, 2009. (C) 2009 Wiley-Liss, Inc.
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STUDY DESIGN: Controlled laboratory study. OBJECTIVE: To evaluate the effect of low-intensity therapeutic ultrasound on the murine calcaneus tendon healing process. BACKGROUND: Therapeutic ultrasound promotes formation and maturation of scar tissue. METHODS: Calcaneus tendon tenotomy and tenorrhaphy was performed on 28 Wistar rats. After the procedure, the animals were randomly divided into 2 groups. The animals in the experimental group received a 5-minute ultrasound application, once a day, at a frequency of 1 MHz, a spatial average temporal average intensity of 0.1 W/cm(2), and a spatial average intensity of 0.52 W/cm(2) at a 16-Hz frequency pulse mode (duty cycle, 20%). Data for the injured side were normalized in relation to the data from the contralateral healthy calcaneus tendon (relative values). The animals in the control group received sham treatment. After a 28-day treatment period, the animals were sacrificed and their tendons surgically removed and subjected to mechanical stress testing. The parameters analyzed were cross-sectional area (mm(2)), ultimate load (N), tensile strength (MPa), and energy absorption (mJ). RESULTS: A significant difference between groups was found for the relative values of ultimate load and tensile strength. The mean +/- SD ultimate load of the control group was -3.5% +/- 32.2% compared to 33.3% +/- 26.8% for the experimental group (P = .005). The mean tensile strength of the control group was -47.7% +/- 19.5% compared to -28.1% +/- 24.1% for the experimental group (P = .019). No significant difference was found in cross-sectional area and energy absorption. CONCLUSION: Low-intensity pulsed ultrasound produced by a conventional therapeutic ultrasound unit can positively influence the calcaneus tendon healing process in rats. J Ort hop Sports Phys Ther 2011;41(7):526-531, Epub 2 February 2011. doi:10.2519/jospt.2011.3468
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Background Roux-en-Y gastric bypass (RYGB) is amongst the commonest surgical intervention for weight loss in obese patients. Gastrocutaneous fistula, which usually occurs along the vertical staple line of the pouch, is amongst its most alarming complications. Medical management comprised of wound drainage, nutritional support, acid suppression, and antibiotics may be ineffective in as many as a third of patients with this complication. We present outcomes after endoscopic application of SurgiSIS (R), which is a novel biomaterial for the treatment of this complication. Design A case series of 25 patients. Methods Twenty-five patients who had failed conservative medical management of gastrocutaneous fistula after RYGB underwent endoscopic application of SurgiSIS (R)-an acellular fibrogenic matrix biomaterial to help fistula healing. Main outcome measures Fistula closure as assessed by upper gastrointestinal imaging and endoscopic examination. Results In patients who had failed medical management lasting 4-25 (median, 7) weeks, closure of the fistulous tract was successful after one application in six patients (30%), two applications in 11 patients (55%), and three applications in three patients (15%). There were no procedure-related complications. Conclusions Endoscopic application of SurgiSIS (R)-an acellular fibrogenic matrix-is safe and effective for the treatment of gastrocutaneous fistula after RYGB.
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Ultrasonometry seems to have a future for the evaluation of fracture healing. Ultrasound propagation velocity (USPV) significantly decreases at the same time that bone diameter decreases as healing takes place, thus approaching normal values. In this investigation, both USPV and broadband ultrasound attenuation (BUA) were measured using a model of a transverse mid-diaphyseal osteotomy of sheep tibiae. Twenty-one sheep were operated and divided into three groups of seven, according to the follow-up period of 30, 60, and 90 days, respectively. The progress of healing of the osteotomy was checked with monthly conventional radiographs. The animals were killed at the end of the period of observation of each group, both operated-upon and intact tibiae being resected and submitted to the measurement of underwater transverse and direct contact transverse and longitudinal USPV and BUA at the osteotomy site. The intact left tibia of the 21 animals was used for control, being examined on a symmetrical diaphyseal segment. USPV increased while BUA decreased with the progression of healing, with significant differences between the operated and untouched tibiae and between the periods of observation, for most of the comparisons. There was a strong negative correlation between USPV and BUA. Both USPV and BUA directly reflect and can help predict the healing of fractures, but USPV alone can be used as a fundamental parameter. Ultrasonometry may be of use in clinical application to humans provided adequate adaptations can be developed. (C) 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 29:444-451, 2011
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The aim of the present study was to evaluate the effect of hyperbaric oxygen therapy (HBO(2)) on the healing process of ischemic colonic anastomoses in rats Forty Wistar rats were divided into four groups control (Group I), control and HBO(2) (Group 11), ischemia (Group III), ischemia and HBO(2) (Group IV) Ischemia was achieved by clamping four centimeters of the colonic arcade On the eighth therapy day, the anastomotic region was removed for quantification of hydroxyproline and immunohistochemical determination of metalloproteinases 1 and 9 (MMP1,MMP9) The immunohistochemical studies showed significantly larger metalloproteinase-labeled areas in Group IV compared with Group III for both MMP1 and MMP9 (p<001) This finding points to a higher remodeling activity of the anastomoses in this experimental group Additionally, animals subjected to hyperbaric oxygen therapy showed both a reduction in interstitial edema and an increase in hydroxyproline concentrations [at the anastomotic site] Therefore, we conclude that HBO(2) is indeed beneficial in anastomotic ischemia
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Epidermal growth factor (EGF) plays an important role in cancer. A functional single nucleotide polymorphism (SNP) in the 5`-untranslated region of the EGF gene (+61 A>G) may influence its expression and contribute to cancer predisposition and aggressiveness. Aiming to investigate the role of EGF +61 A>G in the susceptibility to glioma and its prognosis, we performed a case-control study with 165 patients and 200 healthy controls from Brazil. Comparisons of genotype distributions and allele frequencies did not reveal any significant differences between the groups. The mean overall survival was 9.2 months for A/A, 8.2 months for A/G, and 7.7 months for GIG. When survival curves were plotted we found that the +61G allele is associated with poor overall survival (p=0.023) but not with disease-free survival (p=0.527). Our data suggest that, although there is no association between the EGF +61 A>G genotype and glioma susceptibility, this SNP is associated with shorter overall survival of glioma patients in the Brazilian population. Nevertheless, future studies utilizing a larger series are essential for a definitive conclusion. (Int J Biol Markers 2009; 24: 277-81)
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Introduction: This study evaluated the healing of mandibular condylar fracture in rats submitted to experimental and protein undernutrition (8% of protein) by means of histological analysis. Material: Forty-five adult Wistar rats were divided into three groups of 15 animals: a fracture group, who were submitted to condylar fracture with no changes in diet; an undernourished fracture group, who were submitted to a low protein diet and condylar fracture: an undernourished group, kept until the end of experiment, without condylar fracture. Displaced fractures of the right condyle were created under general anaesthesia. The histological study comprised fracture site and temporomandibular joint evaluations. Results: The undernourished fracture group showed significant weight loss. There was a marked decrease in the values of serum proteins and albumin in the undernourished fracture group. Histological analysis showed that protein undernutrition lead to atrophy of the condylar fibrocartilage. Fractures in undernutrition presented a delay in callus formation due to more extensive devitalized bone areas, and after 3 months there were still bone formation areas, while fibrous ankylosis occurred in the articular space. Conclusion: It was concluded that mandibular condyle fractures in rats with protein undernutrition had impaired callus formation, as well as fibrous ankylosis into the temporomandibular joint. (C) 2010 European Association for Cranio-Maxillo-Facial Surgery.
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Objective. The aim of this study was to assess the effect of cigarette smoke inhalation (CSI) on gene expression in alveolar bone healing sites. Study design. Wistar rats were randomly assigned to the groups: control [animals not exposed to CSI (n = 20)] and test [animals exposed to CSI, starting 3 days before teeth extraction and maintained until killing them (n = 20)]. First mandibular molars were bilaterally extracted, and the expression of alkaline phosphatase, bone morphogenetic protein (BMP) 2 and 7, receptor activator of nuclear factor kappa B ligand, osteoprotegerin, and d2 isoform of vacuolar adenosine triphosphatase V(o) domain were assessed by quantitative polymerase chain reaction in the newly formed tissue in the sockets. Results. Overall, data analysis demonstrated that CSI significantly affected the expression pattern of all of the studied genes except BMP-7. Conclusion. The expression of key genes for bone healing may be affected by CSI in tooth extraction sites. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2010;110:447-452)
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Purpose: The aim of this study was to quantitatively evaluate and qualitatively describe autogenous bone graft healing with or without an expanded polytetrafluoroethylene (e-PTFE) membrane in ovariectornized rats. Materials and Methods: Eighty Wistar rats, weighing approximately 300 g each, were used. A graft was obtained from the parietal bone and fixed to the sidewall of each animal`s left mandibular ramus. The animals were randomly divided into four experimental groups (n = 20 in each group): group 1, sham operated and autogenous bone graft only- group 2, sham operated and autogenous bone graft covered by e-PTFE membrane; group 3, ovariectornized (OVX) and autogenous bone graft only- group 4, OVX and autogenous bone graft covered by e-PTFE membrane. The animals were sacrificed at five different time points: immediately after grafting or at 7, 21, 45, or 60 days after grafting. Histologic examination and morphometric measurement of the sections were performed, and values were submitted to statistical analyses. Results: Both groups (sham and OVX) experienced loss of the original graft volume when it was not covered by the membrane, whereas use of the membrane resulted in additional bone formation beyond the edges of the graft and under the membrane. Histologic analysis showed integration of the grafts in all animals, although a larger number of marrow spaces was found in OVX groups. Conclusions: Association of bone graft with an e-PTFE membrane resulted in maintenance of its original volume as well as formation of new bone that filled the space under the membrane. Osteopenia did not influence bone graft repair, regardless of whether or not it was associated with e-PTFE membrane, but descriptive histologic analysis showed larger numbers of marrow spaces in the bone graft and receptor bed and formation of new bone in the OVX animals. INT J ORAL MAXILLOFAC IMPLANTS 2009;24:1074-1082
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Purpose: To investigate the healing of critical-size cranial bone defects (9-mm-diameter) in guinea pigs treated with a bovine bone-derived resorbable membrane. Materials and Methods: A sample of 42 guinea pigs was divided into test (n = 20), control (n = 20), and standard (n = 2) groups. A full-thickness trephine defect was made in the fronto-parietal bone of each animal. In the test group, the internal and external openings of the defect were each closed with a separate membrane, and the space between them was filled with blood clot and a central spacer. In the control group, the defect was filled only with the blood clot and spacer. At 1, 3, 6, and 9 months later, the calvarias (5 per period) for both the test and control groups were collected, fixed, radiographed, and histologically processed. The Standard-group animals were sacrificed immediately after surgery and used to determine the initial size of defect radiographically. The areas of defects in the radiographs were measured with image-analysis software and were compared between groups and periods by multiple regression analysis with the Bonferroni correction. Results: At 1 and 3 months, newly formed woven bone was histologically observed in both test and control groups. Radiographically, this new bone occupied an average of 32% of the defect area at 1 month and 60% at 3 months in the test group. In the control group, 21% of the defect was filled at 1 month and 39% at 3 months. However, the differences between treatments were not statistically significant (P > .05). At 6 and 9 months, a significant increase in newly formed lamellar bone was seen histologically in both groups. Radiographically, for the test group, the new bone occupied an average of 82% of the defect area at 6 months and 96% at 9 months. For the control group, new bone composed an average of 45% of the defect area at 6 months and 40% at 9 months. The differences between the test and control groups were statistically significant at 6 and 9 months (P < .05). Complete or almost complete filling of the defect was observed in several cases. Conclusion: It was concluded that the bovine bone-derived membrane is highly biocompatible and is able to promote good healing of critical-size defects in calvaria of guinea pig.