RESUMO
Enhanced vascular permeability at the site of injury is a prominent feature in acute inflammatory pain models, commonly assessed through the Evans Blue test. However, this invasive test requires euthanasia, thereby precluding further investigations on the same animal. Due to these limitations, the integration of non-invasive tools such as IRT has been sought. Here, we aimed to evaluate the use of thermography in a common orofacial pain model that employs formalin as a chemical irritant to induce local orofacial inflammation. Male Hannover rats (290-300 g, N = 43) were used. In the first approach, radiometric images were taken before and after formalin administration, assessing temperature changes and extravasated Evans Blue. The second approach included capturing pre- and post-formalin test radiometric images, followed by cytokine measurements in excised vibrissae tissue. Rats were anesthetized for vibrissae tissue collection, allowing correlations between thermographic patterns, nocifensive behavior duration, and cytokine levels in this area. Our findings revealed a positive correlation between local temperature, measured via thermography, and vascular permeability in the contralateral (r2 = 0.3483) and ipsilateral (r2 = 0.4502) side, measured using spectrophotometry. The obtained data supports the notion that thermography-based temperature assessment can effectively evaluate vascular permeability in the orofacial region.
Assuntos
Formaldeído , Termografia , Ratos , Masculino , Animais , Formaldeído/efeitos adversos , Termografia/métodos , Permeabilidade Capilar , Azul Evans/efeitos adversos , Dor Facial/induzido quimicamente , CitocinasRESUMO
Oral traumatic ulcers (OTU) are common in dental routine, and the control of proinflammatory cytokines, such as the tumor necrosis factor-alpha (TNF-α), may interfere with OTU repair. Our aim was to evaluate the role of TNF-α in the healing process of OTU in rats. Wistar male rats were divided into six groups: a control-group (treated with 0.1 mL/kg of saline) and five groups treated with anti-TNF-α infliximab (INF) at 1, 3, 5, 7, and 10 mg/kg immediately before OTU production. The animals were weighed (day 0) and euthanized on days 1, 3, 7, 14 and 21 after ulceration. The ulcers were clinically measured, and the mucosa samples were histologically (scores 0-4), histochemically (collagen assay (pircrosirius)), histomorphometrically (cell counting), and immunohistochemically (TNF-α, α-smooth-muscle-actin (α-SMA), monocyte-chemoattractive-protein-1 (MCP-1), interleukin-8 (IL-8), and fibroblast-growth-factor (FGF)) analyzed. The Evans blue assay was used to measure the vascular permeability. ANOVA-1-2-way/Bonferroni, Kruskal-Wallis/Dunn, and correlation analyses were performed (GraphPad Prism 5.0, p < 0.05). High doses of INF reduced the OTU area (p = 0.043), body mass loss (p = 0.023), vascular permeability (p < 0.001), and reduced delayed histologic scores (p < 0.05), polymorphonuclear (p < 0.001) and mononuclear (p < 0.001) cells, blood vessel counting (p = 0.006), and total (p < 0.001), type-I (p = 0.018), and type-III (p < 0.001) collagen. INF treatment reduced TNF-α immunostaining and delayed MPC-1, FGF, and α-SMA expression, with little/none influence in IL-8 immunostaining. TNF-α blockage by INF reduced acute inflammation in OTU but delayed cell migration and wound healing.
Assuntos
Úlceras Orais , Fator de Necrose Tumoral alfa , Actinas , Animais , Colágeno , Citocinas , Azul Evans/uso terapêutico , Inflamação/tratamento farmacológico , Infliximab/farmacologia , Infliximab/uso terapêutico , Interleucina-8/uso terapêutico , Masculino , Úlceras Orais/tratamento farmacológico , Úlceras Orais/patologia , Ratos , Ratos Wistar , Inibidores do Fator de Necrose Tumoral , Fator de Necrose Tumoral alfa/metabolismo , Úlcera , CicatrizaçãoRESUMO
The blood-brain barrier (BBB) is an active and selective barrier that shields the brain from endogenous and exogenous insults. Different stimuli may lead to the disruption of this barrier, including inflammation and trauma. Several methods are used to evaluate BBB disruption. The most widely used method is Evans blue (EB) dye extravasation. EB cannot normally pass through the BBB and thus its presence in brain tissue indicates alterations in permeability. This protocol details the steps of EB extravasation in rodents. Important aspects regarding critical steps and advantages are also provided. © 2019 by John Wiley & Sons, Inc.
Assuntos
Barreira Hematoencefálica/patologia , Lesões Encefálicas Traumáticas/patologia , Encéfalo/patologia , Azul Evans/metabolismo , Inflamação/patologia , Animais , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Camundongos , RatosRESUMO
OBJECTIVES: To evaluate the sensitivity and specificity of the modified Evans blue dye test compared to the fibre-optic endoscopic evaluation of swallowing to detect aspiration in tracheostomised patients. METHODS: This observational accuracy study included 17 patients hospitalised for respiratory complications, subjected to prolonged intubation, and for this reason, tracheostomised. RESULTS: Mean patient age was 60.2 ± 21.0 years. Aspiration was identified in 10 patients when assessed by fibre-optic endoscopic evaluation of swallowing; of these, 1 had aspiration when evaluated by modified Evans blue dye test. The dye test had a sensitivity of 10.0 per cent and specificity of 100.0 per cent for detecting aspiration. Fibre-optic endoscopic evaluation of swallowing revealed no statistically significant associations between aspiration presence and: speech and language therapy duration, intubation time, or tracheostomy plus mechanical ventilation duration. CONCLUSION: The modified Evans blue dye test is simple and inexpensive, and does not require prior knowledge in endoscopy; it may be used as an initial screening test in all tracheostomised patients for evaluating aspiration. However, fibre-optic endoscopic evaluation of swallowing should be used for a more comprehensive diagnosis of tracheostomy patients, especially for those at high risk for aspiration.
Assuntos
Corantes/administração & dosagem , Transtornos de Deglutição/diagnóstico , Endoscopia/métodos , Azul Evans/administração & dosagem , Tecnologia de Fibra Óptica/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , TraqueostomiaRESUMO
Scorpionism is a relevant public health problem in several countries in tropical and subtropical regions. In Brazil, Tityus serrulatus sting can induce acute lung injury in part as a consequence of inflammation. Despite the occurrence of other scorpions of Tityus genus in Brazilian scorpiofauna, the knowledge regarding pulmonary alterations is related to T. serrulatus venom (Tsv). Here we studied, comparatively, the pathophysiological changes in the rat airways envenomed by Tsv or T. bahiensis venom (Tbv), since both scorpions are involved in human accidents but with severe envenomations occurring when victims are stung by T. serrulatus. After intravenous injection of the venoms (200 µg/kg), both were able to induce Evans blue extravasation (in 30 min) into airways and increased protein extravasation into lungs at 4 and 24 h, but the magnitude of such events was higher in Tsv group. Hemorrhage (in 60 min) in the lungs was higher in Tbv group, while IL-1ß (at 1 h) and IL-6 (at 1 and 4 h) in lung homogenates were detected only in Tsv group. Four and 24 h after envenomation, myeloperoxidase activity in lung was equally augmented in the envenomed groups, as well as an increased in polymorphonuclear cell numbers in bronchoalveolar lavage fluid. At 4 h blood leukogram showed increased leukocyte values with the highest neutrophilia in Tsv group. The numbers of leukocytes and neutrophils remained higher than control at 24 h in Tsv and Tbv groups, and it was accompanied by lympho (envenomed groups) and monocytosis (Tsv group). In conclusion, although Tbv was capable of inducing acute lung injury and blood leukocyte mobilization, most of the evaluated parameters were more affected by the Tsv. These results could help to explain the pathophysiology of the scorpionism and the clinical data arguing toward the greatest severity associated with T. serrulatus stings.
Assuntos
Pulmão/efeitos dos fármacos , Venenos de Escorpião/toxicidade , Escorpiões , Animais , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Permeabilidade Capilar/efeitos dos fármacos , Azul Evans , Hemorragia , Contagem de Leucócitos , Pulmão/enzimologia , Pulmão/fisiopatologia , Masculino , Peroxidase , Ratos Wistar , Especificidade da EspécieRESUMO
BACKGROUND: Malaria-associated acute respiratory distress syndrome (MA-ARDS) is a potentially lethal complication of clinical malaria. Acute lung injury in MA-ARDS shares features with ARDS triggered by other causes, including alveolar inflammation and increased alveolar-capillary permeability, leading to leak of protein-rich pulmonary oedema fluid. Mechanisms and physiologic alterations in MA-ARDS can be examined in murine models of this syndrome. Integrin αDß2 is a member of the leukocyte, or ß2 (CD18), sub-family of integrins, and emerging observations indicate that it has important activities in leukocyte adhesion, accumulation and signalling. The goal was to perform analysis of the lungs of mice wild type C57Bl/6 (a D (+/+) ) and Knockout C57Bl/6 (a D (-/-) ) with malaria-associated acute lung injury to better determine the relevancy of the murine models and investigate the mechanism of disease. METHODS: C57BL/6 wild type (a D (+/+) ) and deficient for CD11d sub-unit (a D (-/-) ) mice were monitored after infection with 10(5) Plasmodium berghei ANKA. CD11d subunit expression RNA was measured by real-time polymerase chain reaction, vascular barrier integrity by Evans blue dye (EBD) exclusion and cytokines by ELISA. Protein and leukocytes were measured in bronchoalveolar lavage fluid (BALF) samples. Tissue cellularity was measured by the point-counting technique, F4/80 and VCAM-1 expression by immunohistochemistry. Respiratory function was analysed by non-invasive BUXCO and mechanical ventilation. RESULTS: Alveolar inflammation, vascular and interstitial accumulation of monocytes and macrophages, and disrupted alveolar-capillary barrier function with exudation of protein-rich pulmonary oedema fluid were present in P. berghei-infected wild type mice and were improved in αDß2-deficient animals. Key pro-inflammatory cytokines were also decreased in lung tissue from α D (-/-) mice, providing a mechanistic explanation for reduced alveolar-capillary inflammation and leak. CONCLUSIONS: The results indicate that αDß2 is an important inflammatory effector molecule in P. berghei-induced MA-ARDS, and that leukocyte integrins regulate critical inflammatory and pathophysiologic events in this model of complicated malaria. Genetic deletion of integrin subunit αD in mice, leading to deficiency of integrin αDß2, alters lung inflammation and acute lung injury in a mouse model of MA-ARDS caused by P. berghei.
Assuntos
Antígenos CD11/metabolismo , Cadeias alfa de Integrinas/metabolismo , Malária/complicações , Síndrome do Desconforto Respiratório/patologia , Animais , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Citocinas/análise , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Azul Evans/metabolismo , Perfilação da Expressão Gênica , Imuno-Histoquímica , Contagem de Leucócitos , Pulmão/patologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Permeabilidade , Plasmodium berghei/crescimento & desenvolvimento , Proteínas/análise , Reação em Cadeia da Polimerase em Tempo Real , Testes de Função RespiratóriaRESUMO
BACKGROUND: Disease manifestations in neurocysticercosis (NCC) are frequently due to inflammation of degenerating Taenia solium brain cysts. Exacerbated inflammation post anthelmintic treatment is associated with leakage of the blood brain barrier (BBB) using Evans blue (EB) staining. How well EB extravasation into the brain correlates with magnetic resonance imaging (MRI) using gadolinium (Gd) enhancement as a contrast agent and pericystic inflammation was analyzed in pigs harboring brain cysts of Taenia solium. METHODOLOGY/PRINCIPAL FINDINGS: Three groups of 4 naturally infected pigs were assessed. The first and second groups were treated with both praziquantel plus albendazole and sacrificed two and five days post treatment, respectively. A third untreated group remained untreated. Pigs were injected with EB two hours prior to evaluation by Gd-enhanced T1-MRI, and euthanized. The EB staining for each cyst capsule was scored (EB grades were 0: 0%; 1: up to 50%; 2: over 50% but less than 100%; 3: 100%). Similarly, the Gd enhancement around each cyst was qualitatively and quantitatively scored from the MRI. The extent of pericystic inflammation on histology was scored in increasing severity as IS1, IS2, IS3 and IS4. Grade 3 EB staining and enhancement was only seen in treated capsules. Also, treated groups had higher Gd intensity than the untreated group. Grades of enhancement correlated significantly with Gd enhancement intensity. EB staining was correlated with Gd enhancement intensity and with IS4 in the treated groups. These correlations were stronger in internally located cysts compared to superficial cysts in treated groups. SIGNIFICANCE: EB staining and Gd enhancement strongly correlate. The intensity of enhancement determined by MRI is a good indication of the degree of inflammation. Similarly, EB staining highly correlates with the degree of inflammation and may be applied to study inflammation in the pig model of NCC.
Assuntos
Imageamento por Ressonância Magnética/métodos , Neurocisticercose/imunologia , Coloração e Rotulagem/métodos , Animais , Encéfalo/patologia , Modelos Animais de Doenças , Azul Evans/química , Histologia , Humanos , Neurocisticercose/diagnóstico por imagem , Neurocisticercose/patologia , SuínosRESUMO
Dyes are the most difficult constituents to remove by conventional biological wastewater treatment. Colored wastewater is mainly eliminated by physical and chemical procedures, which are very expensive and have drawbacks. Therefore, the advantage of using biological processes, such as the biotransformation of dyes, is that they may lead to complete mineralization or formation of less toxic products. To prove the possibility of using fungal processes for decolorization and other applications, the analysis of the toxicity of the processes' products is required. The decolorization of the mixture of two dyes from different classes - triphenylmethane brilliant green and azo Evans blue (GB - total concentration 0.08 g/L, proportion 1:1 w/w) - by Pleurotus ostreatus (BWPH and MB), Gloeophyllum odoratum (DCa), RWP17 (Polyporus picipes) and Fusarium oxysporum (G1) was studied. Zootoxicity (Daphnia magna) and phytotoxicity (Lemna minor) changes were estimated at the end of the experiment. The mixture of dyes was significantly removed by all the strains that were tested with 96 h of experimental time. However, differences among strains from the same species (P. ostreatus) were noted. Shaking improved the efficacy and rate of the dye removal. In static samples, the removal of the mixture reached more than 51.9% and in shaken samples, more than 79.2%. Tests using the dead biomass of the fungi only adsorbed up to 37% of the dye mixture (strain BWPH), which suggests that the process with the living biomass involves the biotransformation of the dyes. The best results were reached for the MB strain, which removed 90% of the tested mixture under shaking conditions. Regardless of the efficacy of the dye removal, toxicity decreased from class V to class III in tests with D. magna. Tests with L. minor control samples were classified as class IV, and samples with certain strains were non-toxic. The highest phytotoxicity decrease was noted in shaken samples where the elimination of dye mixture was the best.
Assuntos
Basidiomycota/crescimento & desenvolvimento , Basidiomycota/metabolismo , Azul Evans/metabolismo , Fusarium/crescimento & desenvolvimento , Fusarium/metabolismo , Corantes de Rosanilina/metabolismo , Águas Residuárias/microbiologia , Animais , Araceae/efeitos dos fármacos , Araceae/fisiologia , Biotransformação , Sobrevivência Celular/efeitos dos fármacos , Daphnia/efeitos dos fármacos , Daphnia/fisiologia , Azul Evans/toxicidade , Corantes de Rosanilina/toxicidade , Purificação da Água/métodosRESUMO
Dyes are the most difficult constituents to remove by conventional biological wastewater treatment. Colored wastewater is mainly eliminated by physical and chemical procedures, which are very expensive and have drawbacks. Therefore, the advantage of using biological processes, such as the biotransformation of dyes, is that they may lead to complete mineralization or formation of less toxic products. To prove the possibility of using fungal processes for decolorization and other applications, the analysis of the toxicity of the processes' products is required. The decolorization of the mixture of two dyes from different classes - triphenylmethane brilliant green and azo Evans blue (GB - total concentration 0.08 g/L, proportion 1:1 w/w) - by Pleurotus ostreatus (BWPH and MB), Gloeophyllum odoratum (DCa), RWP17 (Polyporus picipes) and Fusarium oxysporum (G1) was studied. Zootoxicity (Daphnia magna) and phytotoxicity (Lemna minor) changes were estimated at the end of the experiment. The mixture of dyes was significantly removed by all the strains that were tested with 96 h of experimental time. However, differences among strains from the same species (P. ostreatus) were noted. Shaking improved the efficacy and rate of the dye removal. In static samples, the removal of the mixture reached more than 51.9% and in shaken samples, more than 79.2%. Tests using the dead biomass of the fungi only adsorbed up to 37% of the dye mixture (strain BWPH), which suggests that the process with the living biomass involves the biotransformation of the dyes. The best results were reached for the MB strain, which removed 90% of the tested mixture under shaking conditions. Regardless of the efficacy of the dye removal, toxicity decreased from class V to class III in tests with D. magna. Tests with L. minor control samples were classified as class IV, and samples with certain strains were non-toxic. The highest phytotoxicity decrease was noted in shaken samples where the elimination of dye mixture was the best.
Assuntos
Animais , Basidiomycota/crescimento & desenvolvimento , Basidiomycota/metabolismo , Azul Evans/metabolismo , Fusarium/crescimento & desenvolvimento , Fusarium/metabolismo , Corantes de Rosanilina/metabolismo , Águas Residuárias/microbiologia , Araceae/efeitos dos fármacos , Araceae/fisiologia , Biotransformação , Sobrevivência Celular/efeitos dos fármacos , Daphnia/efeitos dos fármacos , Daphnia/fisiologia , Azul Evans/toxicidade , Corantes de Rosanilina/toxicidade , Purificação da Água/métodosRESUMO
Dyes are the most difficult constituents to remove by conventional biological wastewater treatment. Colored wastewater is mainly eliminated by physical and chemical procedures, which are very expensive and have drawbacks. Therefore, the advantage of using biological processes, such as the biotransformation of dyes, is that they may lead to complete mineralization or formation of less toxic products. To prove the possibility of using fungal processes for decolorization and other applications, the analysis of the toxicity of the processes' products is required. The decolorization of the mixture of two dyes from different classes - triphenylmethane brilliant green and azo Evans blue (GB - total concentration 0.08 g/L, proportion 1:1 w/w) - by Pleurotus ostreatus (BWPH and MB), Gloeophyllum odoratum (DCa), RWP17 (Polyporus picipes) and Fusarium oxysporum (G1) was studied. Zootoxicity (Daphnia magna) and phytotoxicity (Lemna minor) changes were estimated at the end of the experiment. The mixture of dyes was significantly removed by all the strains that were tested with 96 h of experimental time. However, differences among strains from the same species (P. ostreatus) were noted. Shaking improved the efficacy and rate of the dye removal. In static samples, the removal of the mixture reached more than 51.9% and in shaken samples, more than 79.2%. Tests using the dead biomass of the fungi only adsorbed up to 37% of the dye mixture (strain BWPH), which suggests that the process with the living biomass involves the biotransformation of the dyes. The best results were reached for the MB strain, which removed 90% of the tested mixture under shaking conditions. Regardless of the efficacy of the dye removal, toxicity decreased from class V to class III in tests with D. magna. Tests with L. minor control samples were classified as class IV, and samples with certain strains were non-toxic. The highest phytotoxicity decrease was noted in shaken samples where the elimination of dye mixture was the best.(AU)
Assuntos
Animais , Basidiomycota/crescimento & desenvolvimento , Basidiomycota/metabolismo , Azul Evans/metabolismo , Fusarium/crescimento & desenvolvimento , Fusarium/metabolismo , Corantes de Rosanilina/metabolismo , Águas Residuárias/microbiologia , Araceae , Araceae/fisiologia , Biotransformação , Sobrevivência Celular , Daphnia , Daphnia/fisiologia , Azul Evans/toxicidade , Corantes de Rosanilina/toxicidade , Purificação da Água/métodosRESUMO
BACKGROUND: Liver ischemia reperfusion (IR) injury triggers a systemic inflammatory response and is the main cause of organ dysfunction and adverse postoperative outcomes after liver surgery. Pentoxifylline (PTX) and hypertonic saline solution (HTS) have been identified to have beneficial effects against IR injury. This study aimed to investigate if the addition of PTX to HTS is superior to HTS alone for the prevention of liver IR injury. METHODS: Male Wistar rats were allocated into three groups. Control rats underwent 60 minutes of partial liver ischemia, HTS rats were treated with 0.4 mL/kg of intravenous 7.5% NaCl 15 minutes before reperfusion, and HPTX group were treated with 7.5% NaCl plus 25 mg/kg of PTX 15 minutes before reperfusion. Samples were collected after reperfusion for determination of ALT, AST, TNF-alpha, IL-6, IL-10, mitochondrial respiration, lipid peroxidation, pulmonary permeability and myeloperoxidase. RESULTS: HPTX significantly decreased TNF-alpha 30 minutes after reperfusion. HPTX and HTS significantly decreased ALT, AST, IL-6, mitochondrial dysfunction and pulmonary myeloperoxidase 4 hours after reperfusion. Compared with HTS only, HPTX significantly decreased hepatic oxidative stress 4 hours after reperfusion and pulmonary permeability 4 and 12 hours after reperfusion. CONCLUSION: This study showed that PTX added the beneficial effects of HTS on liver IR injury through decreases of hepatic oxidative stress and pulmonary permeability.
Assuntos
Permeabilidade Capilar/efeitos dos fármacos , Azul Evans/farmacologia , Sequestradores de Radicais Livres/uso terapêutico , Hepatopatias/prevenção & controle , Estresse Oxidativo/efeitos dos fármacos , Pentoxifilina/uso terapêutico , Traumatismo por Reperfusão/prevenção & controle , Solução Salina Hipertônica/uso terapêutico , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Modelos Animais de Doenças , Sinergismo Farmacológico , Interleucina-1/sangue , Interleucina-10/sangue , Isquemia/complicações , Peroxidação de Lipídeos/efeitos dos fármacos , Hepatopatias/etiologia , Hepatopatias/patologia , Pulmão/irrigação sanguínea , Pulmão/enzimologia , Masculino , Permeabilidade/efeitos dos fármacos , Peroxidase/metabolismo , Ratos , Ratos Wistar , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/patologia , Fator de Necrose Tumoral alfa/sangueRESUMO
Cysticidal treatment of neurocysticercosis, an infection of humans and pig brains with Taenia solium, results in an early inflammatory response directed to cysts causing seizures and focal neurological manifestations. Treatment-induced pericystic inflammation and its association with blood brain barrier (BBB) dysfunction, as determined by Evans blue (EB) extravasation, was studied in infected untreated and anthelmintic-treated pigs. We compared the magnitude and extent of the pericystic inflammation, presence of EB-stained capsules, the level of damage to the parasite, expression of genes for proinflammatory and regulatory cytokines, chemokines, and tissue remodeling by quantitative PCR assays between treated and untreated infected pigs and between EB-stained (blue) and non stained (clear) cysts. Inflammatory scores were higher in pericystic tissues from EB-stained cysts compared to clear cysts from untreated pigs and also from anthelmintic-treated pigs 48 hr and 120 hr after treatment. The degree of inflammation correlated with the severity of cyst wall damage and both increased significantly at 120 hours. Expression levels of the proinflammatory genes for IL-6, IFN-γ, TNF-α were higher in EB-stained cysts compared to clear cysts and unaffected brain tissues, and were generally highest at 120 hr. Additionally, expression of some markers of immunoregulatory activity (IL-10, IL-2Rα) were decreased in EB-stained capsules. An increase in other markers for regulatory T cells (CTLA4, FoxP3) was found, as well as significant increases in expression of two metalloproteases, MMP1 and MMP2 at 48 hr and 120 hr post-treatment. We conclude that the increase in severity of the inflammation caused by treatment is accompanied by both a proinflammatory and a complex regulatory response, largely limited to pericystic tissues with compromised vascular integrity. Because treatment induced inflammation occurs in porcine NCC similar to that in human cases, this model can be used to investigate mechanisms involved in host damaging inflammatory responses and agents or modalities that may control damaging post treatment inflammation.
Assuntos
Encefalopatias/imunologia , Cistos/imunologia , Inflamação/etiologia , Neurocisticercose/imunologia , Doenças dos Suínos/imunologia , Animais , Anti-Helmínticos/uso terapêutico , Encefalopatias/veterinária , Permeabilidade Capilar , Cistos/veterinária , Azul Evans/metabolismo , Neurocisticercose/tratamento farmacológico , Neurocisticercose/metabolismo , Neurocisticercose/veterinária , Suínos , Doenças dos Suínos/tratamento farmacológico , Doenças dos Suínos/metabolismoRESUMO
BACKGROUND: Temperature, humidity, vision, and particularly odor, are external cues that play essential roles to mosquito blood feeding and oviposition. Entomological and behavioral studies employ well-established methods to evaluate mosquito attraction or repellency and to identify the source of the blood meal. Despite the efficacy of such methods, the costs involved in the production or acquisition of all parts, components and the chemical reagents involved are unaffordable for most researchers from poor countries. Thus, a simple and relatively low-cost method capable of evaluating mosquito preferences and the blood volume ingested is desirable. PRINCIPAL FINDINGS: By using Evans blue (EB) vital dye and few standard laboratory supplies, we developed and validated a system capable of evaluating mosquito's choice between two different host sources of blood. EB-injected and PBS-injected mice submitted to a number of situations were placed side by side on the top of a rounded recipient covered with tulle fabric and containing Aedes aegypti mosquitoes. Homogenates from engorged mosquitoes clearly revealed the blood source (EB- or PBS-injected host), either visually or spectrometrically. This method was able to estimate the number of engorded mosquitoes, the volume of blood ingested, the efficacy of a commercial repellent and the attractant effects of black color and human sweat. SIGNIFICANCE: Despite the obvious limitations due to its simplicity and to the dependence of a live source of blood, the present method can be used to assess a number of host variables (diet, aging, immunity, etc) and optimized for several aspects of mosquito blood feeding and vector-host interactions. Thus, it is proposed as an alternative to field studies, and it could be used for initial screenings of chemical compound candidates for repellents or attractants, since it replicates natural conditions of exposure to mosquitoes in a laboratory environment.
Assuntos
Aedes/fisiologia , Azul Evans/química , Comportamento Alimentar , Animais , Análise Discriminante , Azul Evans/metabolismo , Comportamento Alimentar/efeitos dos fármacos , Feminino , Repelentes de Insetos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Modelos Animais , Espectrofotometria UltravioletaRESUMO
Cysticidal drug treatment of viable Taenia solium brain parenchymal cysts leads to an acute pericystic host inflammatory response and blood brain barrier breakdown (BBB), commonly resulting in seizures. Naturally infected pigs, untreated or treated one time with praziquantel were sacrificed at 48 hr and 120 hr following the injection of Evans blue (EB) to assess the effect of treatment on larval parasites and surrounding tissue. Examination of harvested non encapsulated muscle cysts unexpectedly revealed one or more small, focal round region(s) of Evans blue dye infiltration (REBI) on the surface of otherwise non dye-stained muscle cysts. Histopathological analysis of REBI revealed focal areas of eosinophil-rich inflammatory infiltrates that migrated from the capsule into the tegument and internal structures of the parasite. In addition some encapsulated brain cysts, in which the presence of REBI could not be directly assessed, showed histopathology identical to that of the REBI. Muscle cysts with REBI were more frequent in pigs that had received praziquantel (6.6% of 3736 cysts; n = 6 pigs) than in those that were untreated (0.2% of 3172 cysts; n = 2 pigs). Similar results were found in the brain, where 20.7% of 29 cysts showed histopathology identical to muscle REBI cysts in praziquantel-treated pigs compared to the 4.3% of 47 cysts in untreated pigs. Closer examination of REBI infiltrates showed that EB was taken up only by eosinophils, a major component of the cellular infiltrates, which likely explains persistence of EB in the REBI. REBI likely represent early damaging host responses to T. solium cysts and highlight the focal nature of this initial host response and the importance of eosinophils at sites of host-parasite interaction. These findings suggest new avenues for immunomodulation to reduce inflammatory side effects of anthelmintic therapy.
Assuntos
Encéfalo/parasitologia , Interações Hospedeiro-Parasita , Teníase/veterinária , Animais , Encéfalo/irrigação sanguínea , Encéfalo/patologia , Azul Evans/farmacocinética , Praziquantel/uso terapêutico , Suínos , Taenia solium/patogenicidade , Teníase/tratamento farmacológicoRESUMO
Mast cells and histamine participate in toxic effects of hairs from some caterpillars. This study reports that a crude extract of Morpheis ehrenbergii caterpillar hairs induces in vitro mast cells activation, triggers the release of histamine and causes a rapid urticarial reaction in the rat skin. Heating of the extract abolishes the inflammatory reaction. These results suggest that the use of antihistamines may improve the adverse skin reactions caused by the Mexican caterpillar M. ehrenbergii.
Assuntos
Borboletas/química , Misturas Complexas/toxicidade , Mastócitos/imunologia , Urticária/induzido quimicamente , Animais , Misturas Complexas/administração & dosagem , Misturas Complexas/análise , Misturas Complexas/imunologia , Azul Evans , Histamina/metabolismo , Injeções Intradérmicas , Larva/química , Mastócitos/metabolismo , Ratos , Rutênio Vermelho , Testes de ToxicidadeRESUMO
Denervation of skeletal muscles induces atrophy, preceded by changes in sarcolemma permeability of causes not yet completely understood. Here, we show that denervation-induced Evans blue dye uptake in vivo of fast, but not slow, myofibers was acutely inhibited by connexin (Cx) hemichannel/pannexin1 (Panx1) channel and purinergic ionotropic P2X7 receptor (P2X7R) blockers. Denervated myofibers showed up-regulation of Panx1 and de novo expression of Cx39, Cx43, and Cx45 hemichannels as well as P2X7Rs and transient receptor potential subfamily V, member 2, channels, all of which are permeable to small molecules. The sarcolemma of freshly isolated WT myofibers from denervated muscles also showed high hemichannel-mediated permeability that was slightly reduced by blockade of Panx1 channels or the lack of Panx1 expression, but was completely inhibited by Cx hemichannel or P2X7R blockers, as well as by degradation of extracellular ATP. However, inhibition of transient receptor potential subfamily V, member 2, channels had no significant effect on membrane permeability. Moreover, activation of the transcription factor NFκB and higher mRNA levels of proinflammatory cytokines (TNF-α and IL-1ß) were found in denervated WT but not Cx43/Cx45-deficient muscles. The atrophy observed after 7 d of denervation was drastically reduced in Cx43/Cx45-deficient but not Panx1-deficient muscles. Therefore, expression of Cx hemichannels and P2X7R promotes a feed-forward mechanism activated by extracellular ATP, most likely released through hemichannels, that activates the inflammasome. Consequently, Cx hemichannels are potential targets for new therapeutic agents to prevent or reduce muscle atrophy induced by denervation of diverse etiologies.
Assuntos
Permeabilidade da Membrana Celular/fisiologia , Conexinas/metabolismo , Denervação , Músculo Esquelético/metabolismo , Atrofia Muscular/metabolismo , Sarcolema/metabolismo , Análise de Variância , Animais , Conexina 43/deficiência , Azul Evans/metabolismo , Masculino , Microscopia de Fluorescência , Músculo Esquelético/inervação , Ratos , Ratos Sprague-DawleyRESUMO
The scorpion Tityus serrulatus is responsible for the most severe accidents that have been registered in Brazil, mainly in the state of Minas Gerais (MG), being the lung edema (LE), the main cause of death in these accidents. Although an increased in the number of accidents caused to this species in Federal District (Distrito Federal - DF), it seems that this particular species is not responsible for severe scorpionism cases in this region. Given this observation, we tested the toxicity in mice and compared the ability of T. serrulatus venom from DF (Ts-DF) and Minas Gerais State (Ts-MG) to induce LE in rats. The LD50 of Ts-DF venom was 51.6 µg/mouse, almost twice (1.98) higher than that obtained for Ts-MG venom. The ability of venom (0.5 mg/kg) to induce LE in rats was determined by the wet weight differences between treated and untreated lungs, by pulmonary morphological analyses and by pulmonary vascular permeability (PVP) using the Evans blue protocol. Significant differences in the wet weight of lungs and changes in PVP were found in Ts-MG venom treated rats when compared to rats treated with Ts-DF venom or untreated rats (p < 0.001), but no differences occurred when comparing rats treated with Ts-DF venom and untreated rats (p < 0.05). These results were confirmed by evaluation of pulmonary morphology. Comparison of chromatographic profiles obtained from these venoms (Ts-DF and Ts-MG) using the fractal dimension (D) analysis and the molecular mass fingerprint of the chromatographic fractions showed a higher number of components between 35 and 40% acetonitrile in Ts-MG venom than in Ts-DF venom, indicating a higher diversity of sodium channel modulators in that venom.
Assuntos
Discinesia Induzida por Medicamentos/patologia , Variação Genética , Edema Pulmonar/induzido quimicamente , Venenos de Escorpião/toxicidade , Escorpiões/química , Análise de Variância , Animais , Brasil , Permeabilidade Capilar/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Dispneia/induzido quimicamente , Azul Evans , Fractais , Geografia , Dose Letal Mediana , Contagem de Leucócitos , Masculino , Camundongos , Edema Pulmonar/patologia , Ratos , Ratos Wistar , Venenos de Escorpião/genética , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por MatrizRESUMO
The functions of rapid eye movement (REM) sleep have remained elusive since more than 50 years. Previous reports have identified several independent processes affected by the loss and subsequent recovery of REM sleep (hippocampal neurogenesis, brain stem neuronal cell death, and neurotransmitter content in several brain regions); however, a common underlying mechanism has not been found. We propose that altered brain homeostasis secondary to blood-brain barrier breakdown may explain all those changes induced by REM sleep loss. Therefore, the present report aimed to study the consequences of REM sleep restriction upon blood-brain barrier permeability to Evans blue. REM sleep restriction was induced by the multiple platform technique; male rats were REM sleep restricted 20h daily (with 4h sleep opportunity) during 10 days; control groups included large platform and intact rats. To study blood-brain barrier permeability Evans blue was intracardially administered; stained brains were sliced and photographed for optical density quantification. An independent experiment was carried out to elucidate the mechanism of blood-brain breakdown by transmission electron microscopy. REM sleep restriction increased blood-brain barrier permeability to Evans blue in the whole brain as compared to both control groups. Brief periods of sleep recovery rapidly and effectively restored the severe alteration of blood-brain barrier function by reducing blood-to-brain transfer of Evans blue. The mechanism of blood-brain barrier breakdown involved increased caveolae formation at brain endothelial cells. In conclusion, our data suggest that REM sleep regulates the physical barrier properties of the blood-brain barrier.
Assuntos
Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/ultraestrutura , Recuperação de Função Fisiológica/fisiologia , Privação do Sono/metabolismo , Sono REM/fisiologia , Animais , Barreira Hematoencefálica/patologia , Azul Evans/metabolismo , Masculino , Distribuição Aleatória , Ratos , Ratos Wistar , Privação do Sono/patologiaRESUMO
Neurocysticercosis is a widely prevalent disease in the tropics that causes seizures and a variety into of neurological symptoms in most of the world. Experimental models are limited and do not allow assessment of the degree of inflammation around brain cysts. The vital dye Evans Blue (EB) was injected to 11 pigs naturally infected with Taenia solium cysts to visually identify the extent of disruption of the blood-brain barrier. A total of 369 cysts were recovered from the 11 brains and classified according to the staining of their capsules as blue or unstained. The proportion of cysts with blue capsules was significantly higher in brains from pigs that had received anthelmintic treatment 48 and 120h before the EB infusion, indicating a greater compromise of the blood-brain barrier due to treatment. The model could be useful for understanding the pathology of treatment-induced inflammation in neurocysticercosis.
Assuntos
Anti-Helmínticos/uso terapêutico , Barreira Hematoencefálica/patologia , Neurocisticercose/veterinária , Praziquantel/uso terapêutico , Doenças dos Suínos/patologia , Animais , Anti-Helmínticos/farmacologia , Barreira Hematoencefálica/parasitologia , Encéfalo/parasitologia , Encéfalo/patologia , Corantes , Azul Evans , Extravasamento de Materiais Terapêuticos e Diagnósticos , Neurocisticercose/tratamento farmacológico , Neurocisticercose/patologia , Praziquantel/farmacologia , Suínos , Doenças dos Suínos/tratamento farmacológico , Doenças dos Suínos/parasitologia , Taenia solium/efeitos dos fármacosRESUMO
UNLABELLED: Formalin injected in the knee joint of rats produces concentration-dependent nociception, edema, and plasma leakage (PL). Herein, we investigated the effect of histamine H1 receptor (H1R) antagonists in this model. Articular nociception was inferred from the paw elevation time (PET; seconds) during 1-minute periods of stimulated walking, determined every 5 minutes, throughout a 60-minute experimental session. Edema was evaluated by the increase in articular diameter (AD; mm), and PL was measured by the amount of Evans blue dye in the synovial fluid (PL; µg/mL). Loratadine and cetirizine, given systemically, both increased the PET. None of the treatments changed the AD and PL. Loratadine given locally with formalin increased the PET but was without effect when given in the contralateral knee. Systemic loratadine was also without effect when formalin was coinjected with sodium cromoglycate. Histamine and the selective H1R agonist 2-pyridylethylamine decreased the PET and potentiated morphine spinal analgesia, but did not affect the AD and PL. Cetirizine prevented the antinociceptive effect of the H1R agonist. The N-methyl-D-aspartate/histamine-site agonist tele-methylhistamine coinjected with formalin only increased PET. Serotonin alone had no effect on the PET and increased the AD, and the highest dose increased the PL. When coinjected with formalin, serotonin only caused hypernociception, and the highest dose also increased AD. NAN 190, cyproheptadine, and ondansetron (respectively, 5-HT1, 5-HT2, and 5-HT3 receptor antagonists) decreased the PET without changing the AD or PL. Collectively, these results suggest that in rats, the H1R plays an antinociceptive role within the knee joint, while serotonin receptors play a pronociceptive role. PERSPECTIVE: The present study revealed an antinociceptive mechanism that has previously not been detected by traditional nociceptive tests. Our observations may help to improve the development of new pharmacological strategies for the treatment of clinically relevant pains that generally originate in deep structures.