Effect of low-intensity therapeutic ultrasound on wound healing in rats subjected to third-degree burns

PURPOSE: To determine the effectiveness of low-intensity therapeutic ultrasound (LITUS) on wound healing in rats with third-degree burns. METHODS: Twenty rats were divided into the Control Group that comprised four rats without third-degree burns that did not undergo LITUS, the Burned Group (BG), comprising eight rats with third-degree burns that did not undergo LITUS, and the Burned with Treatment Group (BTG), comprising eight rats with third-degree burns that were administered LITUS. LITUS began 24 h after injury and involved daily applications for 8 min at 0.1 W/cm2 for 14 days. RESULTS: The BTG lost less weight than the BG (Q=2.75; p<0.05). No visible differences were apparent among the groups' lesions on day 4. By the end of treatment, wound healing was more evident in the BTG. No statistically significant differences were found between the BG and the BTG in relation to the parameters measured using the histological changes in burn wound healing scoring system. CONCLUSION: The LITUS protocol applied to the animals with third-degree burns accelerated the formation of fibrin-leukocyte crusts and significantly reduced weight loss. However, burn wound healing was not accelerated.

Platelet-Rich Fibrin Lysate Can Ameliorate Dysfunction of Chronically UVA-Irradiated Human Dermal Fibroblasts

To determine whether platelet-rich fibrin lysate (PRF-L) could restore the function of chronically ultraviolet-A (UVA)-irradiated human dermal fibroblasts (HDFs), we isolated and sub-cultured HDFs from six different human foreskins. HDFs were divided into two groups: those that received chronic UVA irradiation (total dosages of 10 J cm-2) and those that were not irradiated. We compared the proliferation rates, collagen deposition, and migration rates between the groups and between chronically UVA-irradiated HDFs in control and PRF-L-treated media. Our experiment showed that chronic UVA irradiation significantly decreased (p<0.05) the proliferation rates, migration rates, and collagen deposition of HDFs, compared to controls. Compared to control media, chronically UVA-irradiated HDFs in 50% PRF-L had significantly increased proliferation rates, migration rates, and collagen deposition (p<0.05), and the migration rates and collagen deposition of chronically UVA-irradiated HDFs in 50% PRF-L were equal to those of normal fibroblasts. Based on this experiment, we concluded that PRF-L is a good candidate material for treating UVA-induced photoaging of skin, although the best method for its clinical application remains to be determined.

A Pleural Loose Body Mimicking a Pleural Tumor: A Case Report

We present a rare case of a pleural loose body, thought to be a pedunculated pleural tumor, found incidentally in a 58-year-old female. Computed tomography showed a non-enhancing mass, which migrated along the mediastinum and paravertebral area. Thoracoscopic surgery revealed a 4 cm, soap-like mass that was found to be a fibrin body consisting of hyalinized collagen histopathologically. Mobility and the lack of contrast enhancement of a pleural mass are important clues to diagnosing this benign condition.

Fibrinogen, bFGF and VEGF levels during antibiotic therapy in gynecologic cancer: A preliminary report.

The role of angiogenesis in the development of neoplasia has been identified and characterized. However, anti-angiogenic therapeutic intervention still requires more evidence to become recognized and successful. The aim of this study was to evaluate levels of selected proangiogenic factors, such as fibrinogen, vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) in serum of patients with the gynecologic cancer on the first, third and sixth day of antibiotic therapy, routinely administered as a perioperative treatment. In addition, serum concentrations of γ-γ dimers and α-polymers of cross-linked fibrin structure and the degree of bFGF binding with the fibrin network were investigated. Immunohistochemistry staining of the excised tumor tissue was also performed. We observed higher levels of bFGF, VEGF, as well as fibrinogen in patients with gynecologic malignancy, as compared to healthy women. In cancer patients, the concentration of α-polymers and γ-γ dimers of fibrin network increased. Further only γ-γ dimers fraction of fibrin was found to bind to bFGF. Immunohistochemical analysis indicated the presence of bFGF in an excised tumor tissue. In conclusion, the decrease of proangiogenic bFGF and fibrinogen levels in a clinical trial of gynecologic patients may confirm anti-angiogenic properties of selected antibiotic therapy.

Predictive factors for anterior chamber fibrin formation after vitreoretinal surgery / Fatores preditivos para formação de fibrina na câmara anterior após cirurgia vitreorretiniana

Purpose: The aim of this study was to investigate possible predictive factors related to anterior chamber fibrin formation after vitreoretinal surgery in a large series of patients. Methods: The data of 185 eyes of 185 patients submitted to vitreoretinal surgery was reviewed. The following variables were evaluated: the postoperatively presence of fibrin, age, diabetes mellitus, the vitrectomy system gauge (20, 23 or 25 gauge), the type of vitreous substitute, the influence of prior surgical procedures and the combination with cataract extraction. To evaluate predictive factors for anterior chamber fibrin formation, univariate analysis was performed. A multivariate stepwise logistic regression model was adjusted to investigate factors associated with fibrin formation (p<0.05). Results: Fibrinoid anterior chamber reaction was found in 12 (6.4%) patients. For multivariate logistic regression analysis, balanced salt solution (BSS), the chance of fibrin occurrence was 5 times greater (odds ratio 4.83, CI 95% 1.302 - 17.892; p=0.019), while combination with phacoemulsification increased the chance of fibrin formation by 20 times (odds ratio 20, CI 95% 2.480 - 161.347; p=0.005). No significant difference was found regarding other variables. Conclusion: Anterior chamber fibrin formation is an unwanted complication after vitreoretinal surgery. Factors such as combined performance of phacoemulsification and the use of balanced salt solution as a vitreous substitute may predispose the occurrence of this complication. .

Objetivo: Avaliar os possíveis fatores relacionados à formação de fibrina na câmara anterior após cirurgia vitreorretiniana em uma grande série de casos. Métodos: Foi realizado um estudo retrospectivo, observacional, caso-controle, onde os dados de 185 olhos de 185 pacientes submetidos à cirurgia vitreorretiniana foram avaliados. Os seguintes dados foram analisados: presença ou não de fibrina na câmara anterior na primeira semana de pós-operatório, idade, presença ou não de diabetes mellitus, calibre do sistema de vitrectomia utilizado (20,23 ou 25 gauge), substituto vítreo, a influência de cirurgias oftalmológicas prévias e a realização de cirurgia de catarata combinada. Para avaliação dos fatores preditivos para formação de fibrina, a análise univariada foi realizada. O modelo de regressão logística multivariada foi utilizado para investigar os fatores associados com a formação de fibrina (p<0,05). Resultados: A presença de fibrina na câmara anterior foi encontrada em 12 (6,4%) pacientes. Pela análise de regressão logística multivariada, o uso de solução salina balanceada (BSS) como substituto vítreo, a chance da presença de fibrina foi 5 vezes maior (odds ratio 4,83, IC 95% 1,302 - 17,892; p=0,019), enquanto que a realização de cirurgia facoemulsificação combinada aumentou a chance de formação de fibrina 20 vezes (odds ratio 20, IC 95% 2,480 - 161,347; p=0,005). Nenhuma diferença estatisticamente significativa foi encontrada para as outras variáveis. Conclusão: A formação de fibrina na câmara é uma complicação indesejada após cirurgia vitreorretiniana. Fatores como realização de cirurgia de facoemulsificação combinada e ...

Efecto de los anticuerpos antifosfolipídicos en la formación y degradación de la malla de fibrina en pacientes con aborto recurrente / Effect of antiphospholipid antibodies on the formation and lysis of fibrin network in patients with recurrent miscarriage

En el presente trabajo se estudió el proceso de formación y disolución de la malla de fibrina y la generación de plasmina en un grupo de pacientes con aborto recurrente (AR) debido a la presencia de anticuerpos antifosfolipídicos (N= 10), mujeres con AR sin el síndrome antifosfolipídico (SAF) (N= 6) y se comparó con un grupo de mujeres sanas (N= 8). Del grupo de pacientes estudiadas con SAF, nueve fueron positivas para anticuerpos anticardiolipina (aCL), cinco para la anti-b2-glicoproteína I (anti-b2GPI), cuatro para ambos anticuerpos, una para anticuerpos antiprotrombina (aPT) y anticoagulante lúpico (AL). El proceso de formación de la fibrina y su disolución fue estudiado por turbidimetría y la generación de plasmina mediante sustrato cromogénico S2251. Las curvas de polimerización de la(s) paciente(s) con AR sin SAF y AL presentaron un incremento en la pendiente y turbidez final, comparado con las del grupo control de mujeres sanas. La velocidad de disolución del coágulo fue mayor en la paciente con AL (21 ± 0) 10-4 DDO/seg y en las AR sin SAF (19,6 ± 5,7) 10-4 DDO/seg, comparado con el grupo control (14,5 ± 2,8) 10-4 DDO/seg. La generación de plasmina estuvo incrementada solamente en las AR sin SAF (85 ± 24%) comparado con 52 ± 3% en el grupo control, p= 0,005. Los cambios observados en el proceso de polimerización y fibrinólisis de la(s) paciente(s) con AR sin SAF y AL pudieran estar relacionados con el incremento en los niveles de fibrinógeno, mientras que los de la generación de plasmina con la entidad mórbida.

The present work was intended to study the process of fibrin formation and lysis and plasmin generation in a group of patients with recurrent miscarriage (RM), due to the presence of antiphospholipid antibodies (N= 10); as well as in women with RM without the antiphospholipid syndrome (APS) (N= 6), compared with those of a group of healthy women (N= 8). In the group of patients with APS, nine were positive for antibodies against cardiolipin (aCL), five for anti-b2-glycoprotein I (anti-b2GPI), four for both antibodies, and one for antibodies against prothrombin (aPT) and lupus anticoagulant (LA). Fibrin formation and lysis was followed by turbidity and plasmin generation using chromogenic substrate S2251. The polymerization curves from RM patients without APS and the LA patient showed an increased slope and maximum turbidity compared to those of the control group. The speed of lysis was higher in the LA patient (21 ± 0) 10-4 DOD/seg and the RM patients without APS (19.6 ± 5.7) 10-4 DDO/seg, compared to that of the control group (14.5 ± 2.8) 10-4 DDO/seg. Plasmin generation increased only in RM patients without APS (85 ± 24%) against the control group (52 ± 3%), p= 0.005. The changes observed in the fibrin polymerization and lysis process of women with RM without APS and LA seem to be related to their higher fibrinogen levels, while the increased plasmin generation was related to the patients´ morbidity.

Enhanced skin wound healing by a sustained release of growth factors contained in platelet-rich plasma

Platelet-rich plasma (PRP) contains growth factors that promote tissue regeneration. Previously, we showed that heparin-conjugated fibrin (HCF) exerts the sustained release of growth factors with affinity for heparin. Here, we hypothesize that treatment of skin wound with a mixture of PRP and HCF exerts sustained release of several growth factors contained in PRP and promotes skin wound healing. The release of fibroblast growth factor 2, platelet-derived growth factor-BB, and vascular endothelial growth factor contained in PRP from HCF was sustained for a longer period than those from PRP, calcium-activated PRP (C-PRP), or a mixture of fibrin and PRP (F-PRP). Treatment of full-thickness skin wounds in mice with HCF-PRP resulted in much faster wound closure as well as dermal and epidermal regeneration at day 12 compared to treatment with either C-PRP or F-PRP. Enhanced skin regeneration observed in HCF-PRP group may have been at least partially due to enhanced angiogenesis in the wound beds. Therefore, this method could be useful for skin wound treatment.

Production & purification of a fibrinolytic enzyme (thrombinase) from Bacillus sphaericus.

BACKGROUND & OBJECTIVE: Treatment of thromboembolic vascular disease has relied on anticoagulants. However, recognition that lysis of preformed fibrin could be accomplished in vivo by a process involving the conversion of inactive plasminogen to active plasmin enzyme led to an alternative enzyme-based approach. The drugs used for this therapy are called the fibrinolytic enzymes. In this study we attempted the production, purification and characterization of fibrinolytic enzyme from Bacillus sphaericus. METHODS: The seed was prepared in nutrient yeast salt medium (NYSM) in shake flask and organism was produced in 100 l pilot fermentor. Biomass was separated by centrifugation and crude protein was prepared by ammonium sulphate precipitation. Purification was done by ion exchange chromatography using Q sepharose followed by gel filtration chromatography using Sephacryl S- 300. Molecular weight was determined through HPLC. Fibrinolytic activity was assayed by fibrin plate method. RESULTS: The production method yielded 64 mg/l of the crude enzyme and after purification it was 6.3 mg/l. The molecular weight of the compound was 18.6 kDa. INTERPRETATION & CONCLUSION: The enzyme exhibited similar fibrinolytic activity as that of streptokinase, on fibrin plates that were devoid of plasminogen, suggesting that its fibrinolytic action is independent of plasminogen and it is not a plasminogen activator.

Plasma D-dimer levels in patients with typhoid fever.

The plasma levels of D-dimer can be used as a marker of fibrin formation and degradation. Plasma D-dimer levels in the febrile phase of 6 patients with typhoid fever and in the afebrile convalescent phase of 4 of them were measured. D-dimer levels were high in the febrile phase of all 6 patients and within normal range in the afebrile convalescent phase of all 4 patients. Our results indicate that thrombus formation and fibrinolysis may occur in the febrile phase of patients with typhoid fever.

Histopathological evaluation of placentas in IUGR pregnancies.

Gross and microscopic examination was conducted on one hundred placentas. These included twenty five normal controls and seventy five from intrauterine growth retardation (IUGR) pregnancies. Weight of the placentas from IUGR pregnancies were less than those of normal placentas. The incidence of infarction, intervillous fibrin deposition were much higher in IUGR placentas on gross examination. Highly significant increase in the incidence of infarction, intervillous fibrin deposition, stromal fibrosis and syncytial knotting were found in IUGR placentas compared to full term normal placentas on microscopic examination. The incidence of basement membrane thickening and cytotrophoblastic hyperplasis were also higher in IUGR placentas. All the major histologic findings pointed towards reduced blood flow to the placentas resulting in the restriction of blood flow to fetus. The information obtained from their examination can be a useful adjunct in planning and management of future pregnancies.

Effects of Val34Leu and Val35Leu polymorphism on the enzyme activity of the coagulation factor XIII-A

Change in fibrin stabilizing activity of factor XIII A subunit (FXIII-A) caused by a specific mutation, Val34Leu, is recently implicated to incidences of pathophysiology of thrombosis. In an effort to understand the effect of Val34Leu on enhanced catalytic role of FXIII-A, wild type human factor XIII A (HFXIII-A) and mutant HFXIII-A: HFXIII-A (V34L), HFXIII-A (V35L) and HFXIII-A (V34L/V35L) cDNA were expressed in E.coli system where the purified recombinant FXIII-A (rFXIII-A) showed a similar specific transglutaminase activity comparable to the human native FXIII-A from platelet. Using these rFXIII-A mutants, the activation kinetics by thrombin and the enzymatic properties of the activated rFXIII-A were characterized. rFXIII-A (V34L) and rFXIII-A (V34L/V35L) mutants were activated by thrombin much faster than those of wild type rFXIII-A and V35L variant. However, the activated rFXIII-A and mutants showed the identical catalytic efficiency as measured by in vitro assay. These results suggest that ready activation caused by a specific mutation of neighboring thrombin cleavage site(s) in the activation peptide of FXIII-A like V34L resulted in the real-time amount of the activated factor XIII-A that could influence the outcome of fibrin stabilization in vivo such as alpha2- plasmin inhibitor crosslinking to fibrin, a reaction known to be dependent on the initial concentration of active factor-XIII-A.

Expression of cyclooxygenase-1 and -2 in rheumatoid arthritis synovium

The aim of this study was to investigate the expression and localization of cyclooxygenase-1 and -2 (COX-1 and COX-2) in synovial tissues from patients with rheumatoid arthritis (RA). Synovial tissues from 9 patients with RA and 5 patients with osteoarthritis (OA) were examined for COX-1 and COX-2 expressions by immunohistochemical staining using 2 polydonal COX-1 and COX-2 antibodies. In RA synovia, synovial lining cells showed intense immunostaining for COX-1, whereas slight to moderate staining was observed in inflammatory cells, stromal fibroblast-like cells and vascular endothelial cells. There was no significant difference in COX-1 expression between RA and OA synovia. The localization of COX-2 expression dearly differed from that of COX-1 expression, being most intense in inflammatory cells. However, there was no difference in COX-1 and COX-2 expressions between RA and OA synovial tissues. Our observations support that inflammatory mechanisms modulated by COX-1 and COX-2 in chronic RA synovium might be similar to those in chronic OA synovium.

El proceso de calcificación en la placenta humana / The process of calcification in human placental

Con el propósito de conocer el inicio del proceso de la calcificación placentaria y su evolución fueron analizadas con microscopía electrónica de transmisión, histoquímica de v.Kossa para calcio y microscopía electrónica de barrido muestras de placa basal procedentes de embarazo prolongado. Vesícula de matríz no fueron vistas. Densos agregados de minerales parecen fusionarse y formar gránulos cada vez mayores en la degeneración fibrinoide intracelular del sincitio, en células de placa basal, matríz extracelular, estroma vellositario y barrera placentaria. Glóbulos rojos, fibrina, fibrinoide y colágena son posibles núcleadores de cristales de hidroxiapatita. Gránulos que crecen para formar pequeños filamentos, barras y cuerpos tridimencionales irregulares, se ocacionan unos a otros por aposión para formar depósitos minerales en cualquier lugar de la placa basal. Vellosidades que se impregnan uniformemente de estos depósitos se fusionan y forman áreas de infartación calcificada. En conclusión, los resultados presentan imágenes del inicio y desarrollo de la calcificación distrófica

Histochemical study of the villous fibrinoid material in the human full-term placenta

Fibrinoid material from human placental villi was investigated employing histochemical methods. According to the present results, the fibrinoid material seems to consist of glucoproteins containing a neutral mucopolysaccharide and a protein.This protein contains arginine, tyrosine, tryptophan and cysteine. The fibrinoid material displayed histochemical reactions very similar to those of fibrin. However, the insensity of the reactions was always higher in the fibrinoid substance. Histological staininng appears to be more effective in differentiating fibrinoid from fibrin

Evaluation of platelet number and function and fibrinogen level in patients bitten by snakes of the Bothrops genus

Platelet function and plasma fibrinogen levels were evaluated in 14 patients,1O males and 4 females, aged 13-59 years bitten by Bothrops genus snakes. There was a statistical difference (p< 0.05) among plasma fibrinogen levels evaluated 24 and 48 hours after envenomation. There was a tendency towards normalization after 48 hours of treatment. The low platelet number was clear in 24-48 hour evaluations with a tendency towards normalization after 48 hours of treatment (p< 0.05). When platelet function was stimulated by collagen and epinephrine, it appeared to be within normal values. On the other hand, when it was stimulated by adenosine diphosphate (ADP), platelet function was hypoaggregated by a single micromol concentration until 48 hours after treatment. At a 3 micromol concentration, there were alterations only before specific treatment (p < 0.05). Fibrinogen levels and fibrin degradation product (FDP) levels appeared to be altered in 83.33 per cent of patients evaluated. The authors suggest that platelet hypoaggregation is related to decreased fibrinogen and increased FDP levels.

Isolation and purification of plasminogen activator from Yoshida ascites Sarcoma of rats.

The plasminogen activator was purified to the extent of 150-fold from 20,000 x g supernatant of Yoshida ascites Sarcoma by ammonium sulphate precipitation at 33% saturation followed by affinity chromatography on p-aminobenzamidine-Sepharose 4B. The specific activity of the purified activator was 10,260 IU/mg expressed in terms of International units of urokinase, the known activator of plasminogen. The activator was homogeneous by polyacrylamide slab gel electrophoresis with an apparent molecular weight 75 kDa by gel filtration on Sephadex G-100. Analysis by SDS-polyacrylamide gel electrophoresis under reducing conditions, revealed the presence of two subunits of about 48 and 29 kDa. The activator displayed binding preference to fibrin and was immunologically distinguishable from urokinase, indicating that it could be of non-urokinase origin. The preparation further revealed similarity to standard tissue plasminogen activator with respect to fibrin binding and immunological cross reactivity.