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51.
K.S. Fernandes A.H.M. Silva S.A. Mendanha K.R. Rezende A. Alonso 《Brazilian journal of medical and biological research》2013,46(9):780-788
4-Nerolidylcatechol (4-NC) is found in Pothomorphe umbellata
root extracts and is reported to have a topical protective effect against UVB
radiation-induced skin damage, toxicity in melanoma cell lines, and antimalarial
activity. We report a comparative study of the antioxidant activity of 4-NC and
α-tocopherol against lipid peroxidation initiated by two free radical-generating
systems: 2,2′-azobis(2-aminopropane) hydrochloride (AAPH) and
FeSO4/H2O2, in red blood cell ghost
membranes and in egg phosphatidylcholine (PC) vesicles. Lipid peroxidation was
monitored by membrane fluidity changes assessed by electron paramagnetic
resonance spectroscopy of a spin-labeled lipid and by the formation of
thiobarbituric acid-reactive substances. When lipoperoxidation was initiated by
the hydroxyl radical in erythrocyte ghost membranes, both 4-NC and α-tocopherol
acted in a very efficient manner. However, lower activities were observed when
lipoperoxidation was initiated by the peroxyl radical; and, in this case, the
protective effect of α-tocopherol was lower than that of 4-NC. In egg PC
vesicles, malondialdehyde formation indicated that 4-NC was effective against
lipoperoxidation initiated by both AAPH and
FeSO4/H2O2, whereas α-tocopherol was less
efficient in protecting against lipoperoxidation by AAPH, and behaved as a
pro-oxidant for FeSO4/H2O2. The DPPH
(2,2-diphenyl-1-picrylhydrazyl) free-radical assay indicated that two free
radicals were scavenged per 4-NC molecule, and one free radical was scavenged
per α-tocopherol molecule. These data provide new insights into the antioxidant
capacity of 4-NC, which may have therapeutic applications for formulations
designed to protect the skin from sunlight irradiation. 相似文献
52.
Ciro D. Soares Thayná M. L. Morais Roberta M. F. G. Araújo Patrícia F. Meyer Eric A. F. Oliveira Rodrigo M. V. Silva 《Growth factors (Chur, Switzerland)》2013,31(1-2):95-103
Fibroblast growth factor 2 (FGF2) regulates the wound repair process and it is secreted by inflammatory and endothelial cells, and by myofibroblasts. This study aimed to establish the expression patterns of FGF2 and myofibroblastic differentiation during wound healing in rats treated with subcutaneous ozone injection. We created full-thickness excisional wounds in rats, and the healing process was analyzed through morphometric analyses and digital quantification of immunoreactivity of smooth muscle actin and FGF2. Ozone therapy-treated wounds presented granulation tissue with a reduced number of inflammatory cells and greater dermal cellularity, and intense collagen deposition. FGF2 immunoreactivity, microvessel density, and amount of myofibroblasts were significantly higher in treated wounds compared to controls. In conclusion, it was demonstrated that subcutaneous injections of ozone accelerate and ameliorate wound repairing process. Moreover, injectable ozone therapy’s action mechanism may be associated with FGF2 overexpression. 相似文献
53.
Lucas Alves Moura Fernanda Vieira Ribeiro Talita Bianchi Aiello Eliana Ap. De Rezende Duek Enilson Antonio Sallum Francisco Humberto Nociti Junior 《Journal of biomaterials science. Polymer edition》2013,24(10):573-584
The aim of this pilot study was to assess the release of locally delivered doxycycline by poly (l-lactide-co-glycolide) (PLGA) microspheres in the periodontal pocket of patients with chronic periodontitis, treated by non-surgical periodontal therapy. Nineteen sites of non-adjacent teeth of four different patients were evaluated. Five milligram of PLGA microspheres loaded with 16 doxycycline hyclate (DOX) was administered per periodontal site. To quantify DOX released into the periodontal pocket, gingival crevicular fluid (GCF) was collected from the sites on days 2, 5, 7, 10, 15, and 20 after DOX application, and high-performance liquid chromatography was performed. Data were statistically assessed by ANOVA/Tukey test. At days 2, 5, and 7, the DOX concentration was stably sustained (23.33 ± 1.38, 23.4 ± 1.82, and 22.75 ± 1.33 μg/mL, respectively), with no significant differences over these assessment times (p > 0.05). At days 10 and 15, a tendency was observed toward a decrease in DOX concentration (21.74 ± 0.91 and 20.53 ± 4.88 μg/mL, respectively), but a significant decrease in GCF drug concentration (19.69 ± 4.70 μg/mL) was observed only on day 20. The DOX delivery system developed demonstrated a successful sustained release after local administration, as an adjunct to non-surgical periodontal therapy. 相似文献
54.
Glauber Pacelli Gomes de Lima Terezinha Maria de Souza Gabrielle de Paula Freire Davi Felipe Farias Arcelina Pacheco Cunha Nágila Maria Pontes Silva Ricardo Selene Maia de Morais Ana Fontenele Urano Carvalho 《Parasitology research》2013,112(5):1953-1958
This study assessed new insecticidal activities of essential oils from Lippia sidoides and Croton species (Croton zehntneri, Croton nepetaefolius, Croton argyrophylloides, and Croton sonderianus) against Aedes aegypti mosquito. In addition, the acute toxicity upon mice was determined. All essential oils showed inhibition of egg hatching, with IC50 values ranging from 66.4 to 143.2 μg?mL?1, larvicidal activity with LC50 ranging from 25.5 to 94.6 μg?mL?1, and pupicidal action with PC50 ranging from 276.8 to over 500 μg?mL?1. Only L. sidoides, C. zehntneri, and C. argyrophylloides essential oils were able to inhibit the oviposition of female gravid mosquitoes with OD50 values of 35.3, 45.3, and 45.8 μg?mL?1, respectively. Oral acute toxicity in mice showed that C. sonderianus and C. argyrophylloides oils are nontoxic (LD50?>?6,000 mg.kg?1) while C. nepetaefolius, C. zehntneri, and L. sidoides oils are moderately toxic (LD50 3,840; 3,464, and 2,624 mg.kg?1, respectively). The results indicate that these oils are promising sources of bioactive compounds, showing low or no toxicity to mammals. 相似文献
55.
Mariane Maffei Azuma Carolina de Barros Morais Cardoso Renata Oliveira Samuel Camila Barbosa Pipa Suely Regina Mogami Bomfim Luis Gustavo Narciso João Eduardo Gomes-Filho Luciano Tavares Angelo Cintra 《Journal of endodontics》2021,47(2):272-277
IntroductionThis study investigated the effects of omega-3 polyunsaturated fatty acids (ω-3 PUFAs) on serum inflammatory mediators of rats with pulp exposure–induced apical periodontitis.MethodsForty male Wistar rats were divided into the following groups: control, untreated rats (C); control rats treated with ω-3 PUFAs (C-O); rats with pulp exposure–induced apical periodontitis (AP); and rats with pulp exposure–induced apical periodontitis treated with ω-3 PUFAs (AP-O). ω-3 PUFAs were administered orally once a day for 15 days before pulp exposure and continued for 30 days after pulp exposure. The rats were sacrificed, and then blood and jaw samples were collected. Blood analysis was conducted to determine the total number of leukocytes including neutrophils, monocytes, and lymphocytes. Proinflammatory cytokines tumor necrosis factor alpha, interleukin (IL) 6, and IL-17 were quantified by enzyme-linked immunosorbent assay. Histologic analysis was performed to confirm the development of apical periodontitis. The data were statistically evaluated using analysis of variance and the Tukey posttest. The significance level was set at 5%.ResultsThe development of apical periodontitis was confirmed in all infected groups. Bone destruction was larger in the AP group compared with the AP-O group (P < .05). Blood analysis showed that the AP and AP-O groups showed higher numbers of lymphocytes, leukocytes, monocytes, eosinophils, and expressions of tumor necrosis factor alpha and IL-6 compared with the C and C-O groups (P < .05). In contrast, the presence of leukocytes, lymphocytes, and the expression of IL-6 decreased in the AP-O group compared with the AP group (P < .05).Conclusionsω-3 PUFA supplementation influences the systemic effects caused by apical periodontitis, decreasing the number of leukocytes, lymphocytes, and IL-6 in rat blood. 相似文献
56.
Cecilia Amparo Reyes Cevallos Daniel Romeu Benchimol de Resende Carla Andreotti Damante Adriana Campos Passanezi SantAna Maria Lcia Rubo de Rezende Sebastio Luiz Aguiar Greghi Mariana Schutzer Ragghianti Zangrando 《Clinical oral investigations》2020,24(3):1197-1203
This study evaluated clinical outcomes of acellular dermal matrix (ADM) allograft compared with autogenous free gingival graft (FGG) for gingival augmentat 相似文献
57.
Isabel Fragata Teresa Morais Rita Silva Ana Paiva Nunes Petra Loureiro Jos Diogo Martins Jaime Pamplona Rui Carvalho Mariana Baptista Joo Reis 《Interventional neuroradiology》2021,27(1):16
IntroductionMechanical thrombectomy is standard treatment for large vessel occlusion (LVO) in adults. There are no randomized controlled trials for the pediatric population. We report our single-center experience with thrombectomy of LVO in a series of pediatric patients, and perform a review of the literature.MethodsRetrospective review of consecutive pediatric thrombectomy cases between 2011 and 2018. Demographic variables, imaging data, technical aspects and clinical outcome were recorded.ResultsIn a period of 7 years, 7 children were treated for LVO at our center. Median age was 13 (2–17), and median Ped-NIHSS was 15 (3–24), and the median ASPECTS was 8 (2–10). Five patients had cardiac disease, and 2 of them were under external cardiac assistance. Median time from onset of symptoms to beginning of treatment was 7h06m (2h58m–21h38m). Five patients had middle cerebral artery occlusions. Thrombectomy was performed using a stentriever in 3 patients, aspiration in 3 patients, and combined technique in 1 patient. Six patients had good recanalization (TICI 2 b/3). There were no immediate periprocedural complications. At 3 months, 4 patients (57%) were independent (mRS score <3). Two patients died, one after haemorrhagic transformation of an extensive MCA infarct, and one due to extensive brainstem ischemia in the setting of varicella vasculitis.DiscussionSelected pediatric patients with LVO may be treated with mechanical thrombectomy safely. In patients under external cardiac assistance and under anticoagulation, thrombectomy is the only alternative for treatment of LVO. A multidisciplinary approach in specialized pediatric stroke centers with trained neurointerventionalists are essential for good results. 相似文献
58.
Thamyres Fernandes Messa Moreira Sidney Aquino Neto Charly Lemoine Kouakou Boniface Kokoh Cludia Morais Teko Wilhelmin Napporn Paulo Olivi 《RSC advances》2020,10(58):35310
The development of efficient catalysts for ethanol oxidation in alkaline medium requires a synthetic approach that may prevent the surfactant molecules from being adsorbed at the catalytic sites and decreasing the electrochemical performance of the final direct ethanol fuel cell. Toward this goal, the recently reported surfactant-less Bromide Anion Exchange (BAE) method, appears as a promising route to conveniently aim at preparing PtRh alloys dispersed on carbon substrates. The catalysts prepared herein by the BAE method were characterized physicochemically to obtain structural information on the PtRh/C nanomaterials, their morphology (size and shape), and their chemical and surface composition. Electrochemical behavior and properties of these electrodes were then investigated in a half-cell before the implementation of a direct ethanol fuel cell (DEFC) in a home-made anion exchange membrane Teflon cell. The analysis of the electrolytic solution in the anodic compartment by chromatography revealed that acetate was the major reaction product and the carbonate amount increased with the Rh content in the bimetallic composition. With 2.8–3.6 nm particle sizes, the Pt50Rh50/C catalyst exhibited the highest activity towards the ethanol electrooxidation.The development of efficient catalysts for ethanol oxidation in alkaline medium requires an approach that avoids surfactant molecules from being adsorbed at active sites and decreasing the electrochemical performance of the direct ethanol fuel cell. 相似文献
59.
Intercostal nerve transfer to the biceps motor branch in complete traumatic brachial plexus injuries
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Alvaro Baik Cho M.D. Ph.D. Raquel Bernardelli Iamaguchi M.D. Gustavo Bersani Silva M.D. Renata Gregorio Paulos M.D. Leandro Yoshinobu Kiyohara M.D. Luiz Sorrenti M.D. Marcelo Rosa de Rezende M.D. Ph.D. Teng Hsiang Wei M.D. Ph.D. Rames Mattar M.D. Ph.D. Júnior 《Microsurgery》2015,35(6):428-431
The purpose of this report is to critically evaluate our results of two intercostal nerve transfers directly to the biceps motor branch in complete traumatic brachial plexus injuries. From January 2007 to November 2012, 19 patients were submitted to this type of surgery, but only 15 of them had a follow‐up for ≥2 years and were included in this report. The mean interval from trauma to surgery was 6.88 months (ranging from 3 to 9 months). Two intercostals nerves were dissected and transferred directly to the biceps motor branch. The mean follow‐up was 38.06 months (ranging from 24 to 62 months). Ten patients (66.6%) recovered an elbow flexion strength ≥M3. Four of them (26.66%) recovered a stronger elbow flexion ≥M4. One patient (6.25%) recovered an M2 elbow flexion and four patients (26.66%) did not regain any movement. We concluded that two intercostal nerve transfers to the biceps motor branch is a procedure with moderate results regarding elbow flexion recovery, but it is still one of the few options available in complete brachial plexus injuries, especially in five roots avulsion scenario. © 2015 Wiley Periodicals, Inc. Microsurgery 35:428–431, 2015. 相似文献
60.
C F Amaral R A Magalh?es N A de Rezende 《Revista do Instituto de Medicina Tropical de S?o Paulo》1991,33(4):251-255
Three patients presented respiratory abnormalities following Crotalus durissus snakebite. These abnormalities appeared in the first 48 h after the snake bite and consisted of dyspnea, tachypnea, use of accessory muscles of respiration (cases 1 and 2) and flaring of the nostrils (case 2). Cases 1 and 2 developed acute respiratory failure. Case 2, 24 h after the snakebite presented difficult breathing and periods of apnea. He was intubated in the emergency room and transferred to the intensive case unit where he arrive with spontaneous breathing. His respiratory pattern worsened and measurement of arterial pH and blood gases showed metabolic and respiratory acidosis with partial carbon dioxide pressure increasing from 40 to 50.3 mmHg compatible with acute ventilatory failure. Both patients needed mechanical ventilation. Weaning from the ventilator was accomplished after 33 days in case 1 and after 15 days in case 2. Both patients also presented acute renal failure treated with peritoneal dialysis with full recovery of the renal function. Measurements of forced vital capacity (FVC) and forced expiratory volume in the first second (FEV 1.0) was carried out 58 hours after the snakebite in case 3. Both FVC and FEV 1.0 were reduced in relation to the predicted values (60 and 67% respectively) but the ratio FEV 1.0/FVC was in the normal range. These findings were compatible with a restrictive pattern of ventilatory failure. Serial measurements showed progressive increase of both FVC and FEV 1.0 reaching 72 and 79% of the predicted values, respectively, in the 10th day after the snakebite.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献