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Arq. bras. med. vet. zootec. (Online) ; 73(6): 1309-1314, Nov.-Dec. 2021. graf
Article in English | LILACS, VETINDEX | ID: biblio-1355688


The purpose of this study was to assess the efficacy of a blind technique for sciatic and femoral nerve block in rabbit cadavers by evaluating the spread of 1% methylene blue at two different volumes. Nine recently euthanized rabbits weighing 2.5(0.3kg were used. The sciatic (SN) and femoral (FN) nerves of each limb were randomly assigned for injection with 1% methylene blue at 0.2mL/kg (G0.2) or 0.3mL/kg (G0.3). Nerves were dissected and measured for depth and extension of staining (cm). Mean comparisons were performed using paired t test. The relation between volume and nerve staining ( 2cm was assessed using chi-square test. The mean depth of SN was 1.9±0.2 and 1.6±0.3cm and staining 1.9±1.4 and 2.0±1.2cm, respectively in G0.2 and G0.3. No relation was found between depth and dye spread and there was no association between nerve staining ( 2.0cm and volume of solution. The FN failed to be stained in all subjects. In conclusion, SN injection can be successfully performed without guidance in rabbits. The lower volume (0.2mL/kg) is recommended to avoid systemic toxicity.(AU)

O objetivo deste estudo foi avaliar a eficácia de uma técnica para bloqueio às cegas dos nervos isquiático e femoral em cadáveres de coelhos, por meio da avaliação da dispersão de azul de metileno 1% em dois volumes distintos. Nove coelhos recém-eutanasiados, com peso 2,5(0,3kg, foram utilizados. Os nervos isquiático (NI) e femoral (NF) de cada membro foram aleatoriamente designados para injeção com azul de metileno 1% a 0,2mL/kg (G0,2) ou 0,3mL/kg (G0,3). Em seguida, foram dissecados e mensurados em relação à sua profundidade e extensão corada (cm). As médias foram comparadas por meio de teste t pareado. A relação entre volume e extensão corada ( 2cm foi avaliada utilizando-se teste de qui-quadrado. A profundidade média do NI foi 1,9±0,2 e 1,6±0,3cm, e a extensão corada 1,9±1,4 e 2,0±1,2cm, respectivamente, no G0,2 e no G0,3. Não houve relação entre a profundidade e a extensão corada ou entre a extensão corada ( 2,0cm e o volume de solução. Não foi observada coloração do NF em nenhum cadáver. Concluiu-se que a injeção do NI pode ser realizada com sucesso sem auxílio de tecnologias em coelhos. O menor volume (0,2mL/kg) é recomendado para evitar toxicidade sistêmica.(AU)

Animals , Rabbits , Peripheral Nerves , Sciatic Nerve , Methylene Blue/administration & dosage , Nerve Block/methods
Braz. j. med. biol. res ; 53(3): e8853, 2020. tab, graf
Article in English | LILACS | ID: biblio-1089343


Anaphylactic shock can be defined as an acute syndrome, and it is the most severe clinical manifestation of allergic diseases. Anaphylactoid reactions are similar to anaphylactic events but differ in the pathophysiological mechanism. Nitric oxide (NO) inhibitors during anaphylaxis suggest that NO might decrease the signs and symptoms of anaphylaxis but exacerbate associated vasodilation. Therefore, blocking the effects of NO on vascular smooth muscle by inhibiting the guanylate cyclase (GC) would be a reasonable strategy. This study aimed to investigate the effects of NO/cGMP pathway inhibitors methylene blue (MB), Nω-nitro-L-arginine methyl ester hydrochloride (L-NAME), and indigo carmine (IC) in shock induced by compound 48/80 (C48/80) in rats. The effect was assessed by invasive blood pressure measurement. Shock was initiated by C48/80 intravenous bolus injection 5 min before (prophylactic) or after (treatment) the administration of the inhibitors MB (3 mg/kg), L-NAME (1 mg/kg), and IC (3 mg/kg). Of the groups that received drugs as prophylaxis for shock, only the IC group did not present the final systolic blood pressure (SBP) better than the C48/80 group. Regarding shock treatment with the drugs tested, all groups had the final SBP similar to the C48/80group. Altogether, our results suggested that inhibition of GC and NO synthase in NO production pathway was not sufficient to revert hypotension or significantly improve survival.

Animals , Male , Rats , Cyclic GMP/antagonists & inhibitors , Enzyme Inhibitors/administration & dosage , Anaphylaxis/drug therapy , Muscle, Smooth, Vascular/drug effects , Nitric Oxide/antagonists & inhibitors , Rats, Wistar , NG-Nitroarginine Methyl Ester/administration & dosage , Disease Models, Animal , Indigo Carmine/administration & dosage , Methylene Blue/administration & dosage
Arch. argent. pediatr ; 116(4): 612-615, ago. 2018. ilus, tab, graf
Article in Spanish | LILACS, BINACIS | ID: biblio-950053


La metahemoglobinemia es una patología caracterizada por la presencia de altas concentraciones de metahemoglobina en sangre. Esta es una forma oxidada de la hemoglobina, muy afín al oxígeno, que es incapaz de cederlo a los tejidos. Es una entidad poco frecuente, con baja sospecha diagnóstica. Aunque puede ser congénita en recién nacidos con cianosis, es más frecuente la adquirida por fármacos y tóxicos. En la Argentina, no se conoce la incidencia real de esta patología. El objetivo es comunicar un caso de metahemoglobinemia en una paciente pediátrica que ingresó al Hospital Magdalena V. de Martínez con cianosis en la cara y las extremidades, en mal estado general, con el antecedente de ingesta de varios comprimidos de dapsona, y se constató concentración sérica de metahemoglobina del 35%. El tratamiento consistió en la administración endovenosa de azul de metileno. Su evolución fue favorable.

Methemoglobinemia is a condition characterized by a high blood concentration of methemoglobin. Methemoglobinemia is a disorder that occurs when hemoglobin in the blood is oxidized to form methemoglobin, rendering it unable to transport oxygen. Although it can be congenital in cyanotic newborn, it is more often an adverse medication effect. The aim is to report a pediatric methemoglobinemia case, assisted in Magdalena V. de Martínez Hospital, with cyanosis in face and limb, in poor condition, that consumed dapsone accidentally. Her methemoglobin concentration was 35%. Intravenous methylene blue was administered with favorable outcome.

Humans , Female , Child , Cyanosis/chemically induced , Methemoglobinemia/chemically induced , Cyanosis/drug therapy , Dapsone/poisoning , Enzyme Inhibitors/administration & dosage , Methemoglobinemia/drug therapy , Methylene Blue/administration & dosage
Acta cir. bras ; 31(5): 333-337, May 2016. graf
Article in English | LILACS | ID: lil-783795


ABSTRACT PURPOSE: To evaluate the effects of an intraperitoneal solution of methylene blue (MB), lidocaine and pentoxyphylline (PTX) on intestinal ischemic and reperfusion injury METHODS: Superior mesenteric artery was isolated and clamped in 36 adult male Sprague Dawley rats. After 60 minutes, clamp was removed and a group received intraperitoneally UNITO solution (PTX 25mg/kg + lidocaine 5mg/kg + MB 2mg/kg), while the other group was treated with warm 0.9% NaCl solution. Rats were euthanized 45 min after drug administration. Lung and bowel were collected for histological evaluation (using Park's score) and determination of myeloperoxidase (MPO) and malondialdehyde (MDA) levels. RESULTS: Control samples showed lymphoplasmocytic infiltrate and crypt necrosis of villi. MPO and MDA measurements shown no differences between treated and control groups. CONCLUSION: The combination of lidocaine, methylene blue and pentoxyphylline administered intraperitoneally at the studied dose, did not decreased histological lesion scores and biochemical markers levels in intestinal ischemia/reperfusion injury.

Animals , Male , Pentoxifylline/therapeutic use , Reperfusion Injury/drug therapy , Intestines/blood supply , Lidocaine/therapeutic use , Methylene Blue/therapeutic use , Anti-Inflammatory Agents/therapeutic use , Pentoxifylline/administration & dosage , Random Allocation , Peroxidase/metabolism , Models, Animal , Drug Combinations , Drug Synergism , Inflammation/prevention & control , Inflammation/drug therapy , Infusions, Parenteral , Intestines/enzymology , Lidocaine/administration & dosage , Lung/blood supply , Lung/metabolism , Malondialdehyde/metabolism , Methylene Blue/administration & dosage , Anti-Inflammatory Agents/administration & dosage
Arq. bras. oftalmol ; 79(2): 121-122, Mar.-Apr. 2016. graf
Article in English | LILACS | ID: lil-782810


ABSTRACT We report the case of a 70-year-old female patient who developed corneal edema and iris discoloration following the inadvertent use of 1% methylene blue instead of 0.025% trypan blue to stain the anterior capsule during cataract phacoemulsification surgery. Copious irrigation was performed upon realization of incorrect dye use. Corneal edema and iris discoloration developed during the early postoperative period and persisted at 24-months follow-up. However, keratoplasty was not required. The intracameral use of 1% methylene blue has a cytotoxic effect on the corneal endothelium and iris epithelium. Copious irrigation for at least 30 min using an anterior chamber maintainer may improve outcomes.

RESUMO Paciente do sexo feminino com 70 anos de idade desenvolveu edema da córnea e descoloração da íris após o uso inadvertido de 1% de azul de metileno em vez de 0,025% de azul tripano para corar a cápsula anterior do cristalino durante a cirurgia de catarata por facoemulsificação. Foi realizada irrigação abundante quando detectou-se que o corante incorreto tinha sido usado. Edema da córnea e descoloração íris que ocorreu no período pós-operatório precoce persistiu durante 24 meses de seguimento; no entanto, a ceratoplastia não foi necessária. O uso intracameral de 1% de azul de metileno tem efeitos citotóxicos sobre o endotélio da córnea e epitélio da íris. A irrigação abundante durante pelo menos 30 minutos, utilizando um mantenedor de câmara anterior pode resultar em um prognóstico melhor.

Humans , Female , Aged , Phacoemulsification/adverse effects , Medical Errors/adverse effects , Coloring Agents/adverse effects , Methylene Blue/adverse effects , Visual Acuity , Corneal Edema/etiology , Iris/drug effects , Phacoemulsification/instrumentation , Coloring Agents/administration & dosage , Coloring Agents/pharmacology , Injections , Therapeutic Irrigation/methods , Methylene Blue/administration & dosage , Methylene Blue/pharmacology
Braz. oral res. (Online) ; 30(1): e47, 2016. tab, graf
Article in English | LILACS | ID: biblio-951992


Abstract This study was conducted to assess the clinical effect of photodynamic therapy (PDT) in the decontamination of the deep dentin of deciduous molars submitted to partial removal of carious tissue. After cavity preparation, dentin samples were taken from the pulp wall of nineteen deciduous molars before and after PDT application. Remaining dentin was treated with 0.01% methylene blue dye followed by irradiation with an InGaAlP diode laser (λ - 660 nm; 40 mW; 120 J/cm2; 120 s). Dentin samples were microbiologically assessed for the enumeration of total microorganisms, Lactobacillus spp. and mutans streptococci. There was no significant difference in the number of colony-forming units (CFU) for any of the microorganisms assessed (p > 0.05). Photodynamic therapy, using 0.01% methylene blue dye at a dosimetry of 120 J/cm2 would not be a viable clinical alternative to reduce bacterial contamination in deep dentin.

Humans , Male , Female , Child , Photochemotherapy/methods , Tooth, Deciduous/microbiology , Dental Caries/prevention & control , Dentin/drug effects , Enzyme Inhibitors/administration & dosage , Methylene Blue/administration & dosage , Streptococcus mutans/drug effects , Streptococcus mutans/radiation effects , Time Factors , Colony Count, Microbial , Treatment Outcome , Statistics, Nonparametric , Dentin/radiation effects , Dentin/microbiology , Lasers, Semiconductor/therapeutic use , Lactobacillus/drug effects , Lactobacillus/radiation effects
Acta cir. bras ; 29(6): 382-388, 06/2014. graf
Article in English | LILACS | ID: lil-711595


PURPOSE: To determine the minimum volume of methylene blue (MB) to completely color the brachial plexus (BP) nerves, simulating an effective anesthetic block in cats. METHODS: Fifteen adult male cat cadavers were injected through subscapular approach with volumes of 2, 3, 4, 5 and 6 ml in both forelimbs, for a total of 30 brachial plexus blocks (BPB). After infusions, the specimens were carefully dissected preserving each nervous branch. The measurement of the effective area was indicated by the impregnation of MB. Nerves were divided into four segments from the origin at the spinal level until the insertion into the thoracic limb muscles. The blocks were considered effective only when all the nerves were strongly or totally colored. RESULTS: Volumes of 2, 3 and 4 ml were considered insufficient suggesting a failed block, however, volumes of 5 and 6 ml were associated with a successful block. CONCLUSIONS: The injection of methylene blue, in a volume of 6 ml, completely colored the brachial plexus. At volumes of 5 and 6 ml the brachial plexus blocks were considered a successful regional block, however, volumes of 2, 3 and 4 ml were considered a failed regional block. .

Animals , Cats , Male , Anesthesia, Local/veterinary , Brachial Plexus/drug effects , Coloring Agents/administration & dosage , Forelimb/surgery , Methylene Blue/administration & dosage , Neuroanatomical Tract-Tracing Techniques/methods , Shoulder/surgery , Anesthesia, Local/methods , Brachial Plexus/anatomy & histology , Cadaver , Dissection , Forelimb/innervation , Medical Illustration , Nerve Block/methods , Reference Values , Reproducibility of Results , Shoulder/innervation
Article in English | WPRIM | ID: wpr-200215


Preoperative localization is necessary prior to video assisted thoracoscopic surgery for the detection of small or deeply located lung nodules. We compared the localization ability of a mixture of lipiodol and methylene blue (MLM) (0.6 mL, 1:5) to methylene blue (0.5 mL) in rabbit lungs. CT-guided percutaneous injections were performed in 21 subjects with MLM and methylene blue. We measured the extent of staining on freshly excised lung and evaluated the subjective localization ability with 4 point scales at 6 and 24 hr after injections. For MLM, radio-opacity was evaluated on the fluoroscopy. We considered score 2 (acceptable) or 3 (excellent) as appropriate for localization. The staining extent of MLM was significantly smaller than methylene blue (0.6 vs 1.0 cm, P<0.001). MLM showed superior staining ability over methylene blue (2.8 vs 2.2, P=0.010). Excellent staining was achieved in 17 subjects (81%) with MLM and 8 (38%) with methylene blue (P=0.011). An acceptable or excellent radio-opacity of MLM was found in 13 subjects (62%). An appropriate localization rate of MLM was 100% with the use of the directly visible ability and radio-opacity of MLM. MLM provides a superior pulmonary localization ability over methylene blue.

Animals , Ethiodized Oil/administration & dosage , Fluoroscopy , Injections, Subcutaneous , Lung/diagnostic imaging , Methylene Blue/administration & dosage , Preoperative Care , Rabbits , Solitary Pulmonary Nodule/surgery , Staining and Labeling/methods , Thoracic Surgery, Video-Assisted/methods , Thoracoscopy/methods , Tomography, X-Ray Computed
Pesqui. vet. bras ; 33(9): 1062-1070, set. 2013. ilus, tab
Article in Portuguese | LILACS | ID: lil-694052


Descrevem-se os dados epidemiológicos, sinais clínicos e lesões da intoxicação espontânea e experimental por nitrato e nitrito em bovinos alimentados com pastagens de Avena sativa (aveia) e/ou Lolium spp (azevém). A enfermidade ocorre em diferentes regiões do Estado de Santa Catarina, quando as pastagens tem crescimento exuberante, após receberem quantidades excessivas de adubo químico e/ou orgânico, principalmente quando ocorrem condições climáticas de seca e posteriormente chuva. Os animais em contato com essas pastagens desenvolvem rapidamente mucosas de coloração marrom, taquipnéia, andar cambaleante, micção frequente, timpanismo, decúbito lateral e morte em poucos minutos, ou recuperação algumas horas após. Na necropsia de quatro animais que adoeceram espontaneamente, as principais alterações encontradas foram a coloração marrom das mucosas, a cor escura do sangue (cor de chocolate) e a coloração vermelho intensa da musculatura esquelética e do miocárdio esquerdo. A reprodução experimental da doença foi realizada em sete bovinos, com pastagens de quatro propriedades onde ocorreu adoença. Aveia e/ou azevém verdes e sob a forma de feno foram administradas aos bovinos. Destes bovinos quatro morreram, dois adoeceram e se recuperam, um naturalmente e outro com a aplicação de azul de metileno a 1%, na dose de 2mg/kg/peso vivo, e um bovino não apresentou alterações. Os sinais clínicos observados e as lesões nos animais que adoeceram e morreram foram idênticos aos casos naturais. Alterações microscópicas não foram observadas nos casos naturais e experimentais. O teste da difenilamina nas amostras de pastagens onde ocorreram os surtos resultou positivo em todas as propriedades. A análise bromatológica realizada em amostras coletadas de várias propriedades em que ocorreram surtos revelou de 0,30 a 3,36% de nitrato na matéria seca. A enfermidade caracterizou-se principalmente por respiração ofegante, sangue de coloração escura, mucosas de coloração marrom e morte rápida dos bovinos e está relacionada á ingestão de pastagens de aveia e/ou azevém super adubados, que acumularam alto teor de nitrato, após um período de chuvas precedido de seca.

Epidemiological data, clinical and pathological findings of the spontaneous andexperimental poisoning by nitrate and nitrite in cattle fed oats (Avena sativa) and/or ryegrass (Lolium spp.), diphenylamine test, and the nitrate content in the samples of the pasture where the outbreaks occurred, are described. The disease occurs in different regions of the State of Santa Catarina, in which pastures have exuberant growth, after receiving excessive amounts of chemical and/or organic fertilizer, mainly when raining occurs after a period of dry wheather. The animals grazing these pastures quickly develop brown mucosa, tachypnea, staggering gait, frequent urination, bloating, lateral recumbency and death in few minutes or hours. At necropsy of four animals that died spontaneously, the main lesions found were brown mucosa, dark color of the blood (chocolate), intense red color of the skeletal muscles and of the left part of the myocardium. The experimental reproduction of the disease was performed in seven cattle, with pastures from four farms where the disease occurred. The animals were fed with fresh oats and ryegrass and/or hay of it. Four animals died, two became ill and recovered, and one was treated with 2mg/kg per body weight of methylene blue 1%, and one cattle did not show changes. Clinical signs and lesions of the diseased animals that died were similar to natural cases. Microscopic changes were not observed in spontaneous and experimental poisoning. The diphenylamine test was positive in all the farms where the outbreaks occurred. The chemical analysis performed on samples of the pastures from several farms, in which outbreaks of the disease occurred, ranged from 0.30to 3.36% of nitrate in the dry matter. The disease is associated with the ingestion of oats and/or ryegrass pastures heavily fertilized, which accumulates high levels of nitrate after a period of rain and is characterized by rapid breathing, dark-colored blood, brown mucous and rapid death.

Animals , Cattle , Avena/poisoning , Methylene Blue/administration & dosage , Poisoning/veterinary , Lolium/poisoning , Nitrates/toxicity , Nitrites/toxicity , /analysis , Diphenylamine
Article in English | WPRIM | ID: wpr-35150


Acute generalized exanthematous pustulosis is a rare severe pustular cutaneous adverse reaction characterized by a rapid clinical course with typical histological findings. It is accompanied by fever and acute eruption of non-follicular pustules overlying erythrodermic skin. The causative agents are most frequently antibacterial drugs. We present a patient with acute generalized exanthematous pustulosis caused by methylene blue and indigotin dyes.

Acute Generalized Exanthematous Pustulosis/chemically induced , Administration, Oral , Adrenal Cortex Hormones/therapeutic use , Aged , Biopsy , Coloring Agents/administration & dosage , Humans , Indoles/administration & dosage , Intradermal Tests , Male , Methylene Blue/administration & dosage , Skin/drug effects , Treatment Outcome
Rev. clín. pesq. odontol. (Impr.) ; 6(3): 249-257, set.-dez. 2010. ilus, tab, graf
Article in Portuguese | LILACS, BBO | ID: lil-617391


Objetivos: O objetivo do presente estudo foi avaliar a infl uência das alterações na concentração defotossensibilizador e fl uência de energia de irradiação de laser vermelho (660 nm) na viabilidade de culturasbacterianas derivadas de dentina cariada humana após a aplicação da terapia fotodinâmica (TFD)mediada pelo azul de metileno (AM). Material e método: Utilizaram-se culturas bacterianas derivadasde amostras de dentina cariada de pacientes e uma linhagem de Escherichia coli. Utilizaram-se formulaçõesde azul de metileno nas concentrações de 25 e 50 μg/mL para a aplicação da TFD. Foi utilizada fonte delaser vermelho (660 nm) na potência de 40 mW com três fl uências diferentes (6,8; 20,55 e 61,65 J/cm²).Resultados: O tratamento com AM nas duas concentrações testadas (25 e 50 μg/mL) não apresentouatividade antimicrobiana em todas as culturas bacterianas testadas. Para as culturas bacterianas derivadasde dentina cariada, a fl uência de energia de 6,8 J/cm² não promoveu efeito fotodinâmico quando combinadacom AM; as energias de 20,55 e 61,65 J/cm² foram efetivas na redução da carga microbiana, sendoa fl uência de 61,65 J/cm² a mais indicada para a aplicação da TFD antimicrobiana. As culturas de E. coliforam suscetíveis à atividade antibacteriana da TFD nas três fl uências de energia testadas. Conclusão:Os resultados demonstram que a TFD mediada pelo AM nas duas concentrações testadas (25 e 50 μg/mL)e combinada com a irradiação de laser nas fl uências de 20,55 e 61,65 J/cm², promoveu uma diminuiçãosignifi cativa da carga bacteriana das culturas derivadas de amostras de dentina cariada testadas.

Objectives: The aim of this study was to evaluate the effi cacy of antimicrobial photodynamic therapy (PDT)mediated by methylene blue (MB) in two concentrations (25 e 50 μg/mL) and different red laser (660 nm) energyirradiation on bacterial suspensions derived from infected carious dentine samples. Material and method:Bacterial suspensions derived from infected dentine samples and Escherichia coli cell suspensions were used inthis study. MB in two concentrations (25 e 50 μg/mL) alone or in combination with red laser (660 nm) irradiationin different energies (6,8; 20,55 e 61,65 J/cm²) were used to apply PDT in the bacterial suspensions. Results:MB alone had no signifi cant antibacterial effect against the tested bacterial suspensions. In bacterial suspensionsderived from infected carious dentine, MB combined with 6,8 J/cm² laser irradiation did not show the antibacterialeffect of PDT. Laser irradiation with 20,55 e 61,65 J/cm² combined with MB treatment, produced a signifi cantantibacterial effect, but 61,65 J/cm² was the most effective tested laser energy. Bacterial suspensions of E. coli weredecreased their bacterial load in all tested laser energies. Conclusion: The results presented in this study suggestthat PDT mediated by MB in both tested concentrations (25 e 50 μg/mL) could be used in effectively antibacterialclinical protocols in dentistry.

Dental Caries/drug therapy , Escherichia coli/drug effects , Methylene Blue/administration & dosage , Photochemotherapy , Analysis of Variance , Bacterial Load/radiation effects , Dentin/microbiology , Stem Cells , Time Factors , Treatment Outcome
Indian J Pediatr ; 2008 Mar; 75(3): 245-7
Article in English | IMSEAR | ID: sea-83898


OBJECTIVE: The study compares the decline in blood methemoglobin (MetHb) level in children of dapsone intoxication treated with intermittent and continuous methylene blue therapy. METHODS: Eleven children with history of accidental dapsone ingestion and suggestive clinical features of dapsone intoxication were studied. Patients were randomized into two groups: Gr I (n=5) received intermittent methylene blue therapy, while Gr II (N=6) as continuous infusion. The dose of methylene blue was same in both groups. MetHb level in blood was assessed by spectrophotometer at admission and thereafter 12hrly up to 72 hrs. The decline in MetHb was statistically analyzed with student t-test. RESULTS: Six patients had history of seizure and altered sensorium. Severe anemia was observed in 2 patients. The mean levels of MetHb in Gr II was statistically significant after 12, 24, 36, 48 and 72 hrs of methylene blue therapy as compared to Gr I. CONCLUSION: Continuous I.V methylene blue therapy causes significant decline in MetHb level and is more effective in treatment of methemoglobinemia as compared to intermittent regimen.

Anti-Infective Agents/poisoning , Child, Preschool , Dapsone/poisoning , Enzyme Inhibitors/administration & dosage , Female , Humans , Infusions, Intravenous , Male , Methemoglobinemia/chemically induced , Methylene Blue/administration & dosage
Arq. bras. cardiol ; 87(4): 525-532, out. 2006. graf
Article in Portuguese, English | LILACS | ID: lil-438241


OBJETIVO: Benefícios clínicos obtidos pelo azul de metileno (AM) no tratamento da vasoplegia induzida pela ação do óxido nítrico (NO) têm sido relatados na sepse, na síndrome da resposta inflamatória sistêmica (SIRS) em cirurgia cardíaca e no choque anafilático, mas a sua segurança é muitas vezes questionada, principalmente relacionada aos seus efeitos hemodinâmicos e à possibilidade de causar disfunção endotelial. O objetivo deste estudo foi examinar os efeitos hemodinâmicos e a função endotelial da infusão endovenosa in vivo do AM em porcos. MÉTODOS: O protocolo de estudo incluiu dois grupos experimentais de porcas fêmeas: Grupo I (Controle) - os animais (n = 6) não receberam AM; Grupo II (AM) - os animais receberam 3 mg/kg de AM em forma de bolus endovenoso. Após quinze minutos de registro dos parâmetros hemodinâmicos os animais foram sacrificados por exsangüinação, e os estudos in vitro foram conduzidos usando segmentos de artérias coronária, hepática, mesentérica superior, renal, para determinar o efeito do AM na função endotelial relacionada com a liberação de NO. Mediu-se também o NO plasmático nos dois grupos experimentais. RESULTADOS: Os resultados obtidos no presente estudo foram: 1) a infusão endovenosa de AM (3,0 mg/kg) não causou nenhuma alteração hemodinâmica significativa; 2) os valores absolutos e porcentuais e nitrito/nitrato plasmático (NOx) não apresentaram diferenças nos dois grupos experimentais; 3) o estudo in vitro dos segmentos arteriais (coronária, hepática, renal e mesentérica superior) não apresentou disfunção endotelial nos dois grupos. Os resultados sugerem que a injeção endovenosa de AM é segura. Esse dado concorda com dados clínicos no qual o AM foi utilizado para tratar a síndrome vasoplégica após circulação extracorpórea, síndrome da resposta infamatória sistêmica (SIRS) e anafilaxia. Os resultados não foram inesperados porque os animais não apresentavam vasoplegia, não se esperando que a inibição da guanilatociclase tenha algum efeito...

OBJECTIVE: Clinical benefit of methylene blue (MB) treating NO-induced vasoplegia has been reported in sepsis, systemic inflammatory response syndrome (SIRS) in cardiac surgery and anaphylactic shock, but its safety is sometimes questioned, mainly regarding its hemodynamic effects and the possibility of causing endothelium dysfunction. To examine the nitric oxide plasma levels and cardiovascular effects of the infusion of MB in vivo and its effects on endothelium-dependent and endothelium-independent in vitro vascular relaxation. METHODS: The study protocol included two experimental groups of female pigs: Group I (Control) - the animals (n=6) did not receive MB; Group II (MB) - the animals received 3 mg/kg of MB intravenous bolus infusion. After fifteen minutes of hemodynamic parameter recording the animals were sacrificed by exsanguination, and in vitro studies were conducted using segments of coronary, hepatic, superior mesenteric and renal arteries, to determine the effect of MB on the arterial endothelium function with regard to NO release. Nitric oxide plasma levels (NOx) were measured in each of the experimental groups. RESULTS: The results obtained in the present investigation were: 1) intravenous infusion of MB (3.0 mg/kg) caused no hemodynamic changes; 2) absolute and percent plasma NOx values did not differ between the experimental groups; and 3) in vitro study of vascular relaxation showed no significant difference between groups. These results show that MB intravenous infusion seems to be safe. This finding agrees with data from clinical experiments where MB was used to treat vasoplegic syndrome after cardiopulmonary bypass, systemic inflammatory response syndrome (SIRS) and anaphylaxis. These results were not unexpected because, as in healthy subjects, hemodynamics is only fine tuned and not fully under NO control; therefore, MB inhibiting guanylyl cyclase is not expected to do anything...

Animals , Female , Endothelium, Vascular/drug effects , Enzyme Inhibitors/administration & dosage , Methylene Blue/administration & dosage , Nitric Oxide/blood , Vascular Resistance/drug effects , Endothelium, Vascular/physiopathology , Enzyme Inhibitors/pharmacology , Infusions, Intravenous , Luminescent Measurements , Methylene Blue/pharmacology , Nitrates/blood , Nitrites/blood , Sus scrofa , Vascular Resistance/physiology
Article in English | WPRIM | ID: wpr-214437


BACKGROUND: Endogenous nitric oxide (NO) induces the peripheral vasodilation via the activation of guanylate cyclase in patients with septic shock. The purpose of this study was to assess the acute effects of methylene blue (MB), which is an inhibitor of guanylate cyclase, on the hemodynamics and on the production of pro-inflammatory cytokines and nitric oxide (NO) in patients with refractory septic shock. METHODS: Twenty consecutive patients with refractory septic shock, which was defined as shock refractory to a dopamine infusion of more than 20 microgram/kg/min with the appropriate use of antibiotics and adequate volume replacement, received MB infusion of 1 mg/kg intravenously. The hemodynamic and respiratory variables were measured at baseline, 30, 60 and 120 min after an infusion of MB (1 mg/kg). The blood levels of NO, IL-1, IL-10 and TNF-alpha were measured at baseline, 30 and 120 min after MB infusion. RESULTS: The administration of MB induced an increase in the systemic vascular resistance (SVR) that resulted in an increase of the mean arterial pressure (MAP) in patients with refractory septic shock, and this was without a decrease in cardiac output. The administered MB induced an increase in pulmonary vascular resistance (PVR) that resulted in an increase of pulmonary arterial pressure (PAP), without any deterioration of gas exchange. However, the increases in SVR and PVR were not associated with the alteration of endogenous production of NO, IL-1, IL-10 and TNF-alpha. CONCLUSION: MB transiently elevated the MAP by increasing the SVR without altering the endogenous productions of NO, IL-1, IL-10 and TNF-alpha during the study period in patients with refractory septic shock.

Anti-Infective Agents, Urinary/administration & dosage , Blood Pressure/drug effects , Comparative Study , Cytokines/blood , Enzyme-Linked Immunosorbent Assay , Female , Humans , Infusions, Intravenous , Male , Methylene Blue/administration & dosage , Middle Aged , Pulmonary Circulation/drug effects , Retrospective Studies , Shock, Septic/blood , Treatment Outcome , Vascular Resistance/drug effects
Rev. bras. cir. cardiovasc ; 19(1): 17-23, jan.-mar. 2004. tab, graf
Article in Portuguese | LILACS | ID: lil-363354


OBJETIVO: Estudar em pacientes submetidos à cirurgia de revascularização miocárdica com circulação extracorpórea os efeitos da infusão de azul de metileno na reação inflamatória sistêmica e nas condições hemodinâmica e laboratorial. MÉTODO: Foram estudados 60 pacientes randomizados em dois grupos, utilizando-se a infusão de azul de metileno em um dos dois grupos. Amostras de sangue foram colhidas antes da indução anestésica, 3, 6, 24 e 48 horas após o término da circulação extracorpórea para dosagens dos marcadores de inflamação (IL-1b, IL-6, IL-8, IL-10, IL-12p40 e TNFa), NO, gasometria e outras dosagens de rotina. RESULTADOS: O grupo que utilizou azul de metileno mostrou, em diferentes momentos das coletas, maior resistência vascular sistêmica, menor concentração de TNFa, menor número de leucócitos e neutrófilos e menor nível de óxido nítrico. Não ocorreram efeitos adversos importantes. CONCLUSÕES: A infusão de azul de metileno não evidenciou alterações clínicas ou pulmonares adversas, mostrando uma tendência menor à resposta inflamatória sistêmica, menores níveis de óxido nítrico e melhor estabilidade hemodinâmica.

Humans , Methylene Blue/administration & dosage , Methylene Blue/adverse effects , Systemic Inflammatory Response Syndrome/etiology , Cytokines , Extracorporeal Circulation , Myocardial Revascularization , Nitric Oxide , Prospective Studies
Al-Azhar Medical Journal. 2003; 32 (3-4): 599-608
in English | IMEMR | ID: emr-61389


In a prospective study of 24 patients, methylene blue dye was used as an alternative to the isosulfan blue to localize the sentinel lymph node in breast cancer patients. The methylene blue dye technique was successful in 85.7% of patients after excluding the initial learning cases. These results are almost similar for isosulfan blue dye. The study described methylene blue dye localization as a successful alternative to isosulfan blue dye in identifying the sentinel node in breast cancer patients. The methylene blue dye is easily available in most of the Egyptian institutes, safe material, with a very low cost and is readily available to all surgeons

Humans , Female , Sentinel Lymph Node Biopsy , Methylene Blue/administration & dosage , Lymphatic Metastasis
Rev. bras. odontol ; 58(3): 198-200, maio-jun. 2001. graf
Article in Portuguese | LILACS, BBO | ID: lil-296754


Dentes humanos extraídos tiveram seus canais obturados pela técnica da condensaçäo lateral com o cimento Sealer Plus, tendo como controles os cimentos Fill Canal e CRCS. Os dentes foram mergulhados em soluçäo de azul de metileno a 2 por cento, em ambiente com vácuo, e as infiltraçöes marginais avaliadas linearmente. Os mesmos dentes foram dissolvidos em ácido nítrico, sendo o soluto analisado com o auxílio de um espectrofotômetro, objetivando observar o volume da soluçäo traçadora infiltrada. Os resultados evidenciaram, que o Sealer Plus foi o cimento obturador que melhor selou os canais

Dental Cements/analysis , Dental Cements/therapeutic use , Dental Leakage/prevention & control , Root Canal Obturation/methods , Outcome Assessment, Health Care , Analysis of Variance , Methylene Blue/administration & dosage , Quality Control
São Paulo; s.n; 2001. 132 p. ilus.
Thesis in Portuguese | SES-SP, LILACS, SES-SP, SESSP-IDPCPROD, SES-SP | ID: biblio-1068831


Choque de adequada reposição volêmica, alterações da perfusão tecidual, oligúria, acidose láctica e alterações do nível de consciência. O choque séptico permanece como a maior causa de óbito em unidades de terapia intensiva, com mortalidade estimada entre 35% e 60%. Em 1990, vários grupos de forma independente descobriram que o aumento endógeno de óxido nítrico contribuía para a hipotensão e hiporreatividade vascular a agentes vasoconstritores, observadas em modelos animais de choque endotóxico. No presente trabalho, ratos wistar foram submetidos ao implante de um sensor de fluxo vascular com o objetivo de avaliar o débito cardíaco.Um período de recuperação pós-cirurgia de sete a dez dias em média foi observado, 48 horas antes da realização do experimento. Os animais foram submetidos a implante de cateteres em veia jugular direita, artéria carótida esquerda e artéria femoral esquerda. Administrou-se lipopolissacarídeo 50 mg/kg por via venosa e o protocolo era iniciado somente quando ocorria uma redução de 40% na pressão arterial média dentro dos primeiros 30 minutos. Assim, as drogas foram administradas conforme o grupo estudado: Grupo Controle - com placebo 0,2 ml de solução salina a 0,9%, Grupo Azul de Metileno - Azul de Metileno solução a 5% na dose de 5 mg/kg diluídos em solução salina a 0,9%, Grupo L-NAME - L-NAME na dose de 30 mg/kg diluídos em solução salina a 0,9%. Após a injeção de placebo ou drogas, a pressão arterial média, a freqüência cardíaca, o índice cardíaco, índice de resistência vascular sistêmica e o índice de volume sistólico foram monitorados de forma contínua por um período aproximado de 100 minutos. Ao final do experimento, foram coletadas amostras de sangue, para dosagem de renina plasmática, e retirados rim, coração e pulmão para dosagem da atividade da enzima conversora e atividade da óxido nítrico sintase isoforma indutível.

Rats , Shock, Septic/therapy , Hypotension/physiopathology , Hypotension/therapy , Rats, Wistar , Methylene Blue/administration & dosage , NG-Nitroarginine Methyl Ester/antagonists & inhibitors , Nitric Oxide/adverse effects