Evaluation of Paracoccidioides brasiliensis exoantigen in the detection of delayed dermal hypersensitivity in experimental and human paracoccidioidomycosis

The exoantigen of Paracoccidioides brasiliensis standardized by Camargo et al. [1] (AgR) was used to evaluate the in vivo and in vitro cell immune response of experimental animals and of patients with paracoccidioidomycosis (PBM). Fava Netto antigen (AgF) was tested in parallel as a control antigen. The study was conducted with mice and guinea pigs infected with P. brasiliensis or immunized with its fungal antigens, on patients with PBM and on their respective control groups. The cell immune response was analysed by skin tests, and by the macrophage and leucocyte migration inhibition tests (MMIT and LMIT) in the animals and in the patients, respectively. The skin test with AgR as paracoccidioidin was positive in infected or immunized mice and guinea pigs and negative in control animals. The skin tests with AgR (24 h) showed 96.7% positivity in patients with PBM and were negative in control individuals. Histopathological study of the in vivo tests in the different experimental models was consistent with a delayed hypersensitivity response (DHR). Immunohistochemical study of the skin tests of PBM patients demonstrated a predominance of T lymphocytes, confirming the nature of a DHR to the fungal antigens. The in vitro cell immune response showed variable results for the various experimental models, i.e. significant rates of MMIT in immunized mice, a tendency to positivity in infected guinea pigs, and the absence of migration inhibition in PBM patients. Taken together, the data indicate that the AgR is efficient as paracoccidioidin in the evaluation of DHR in PBM, with an optimum time of reading the test of 24 h.

Effect of the Clinical Application of the GaA1As Laser in the Treatment of Dentine Hypersensitivity

Objective: The aim of this study was to evaluate the effectiveness of the clinical use of the gallium-aluminum-arsenium (GaAlAs) laser at the maximum and minimum energies recommended by the manufacturer for the treatment of dentine hypersensitivity. Background Data: Dentine hypersensitivity (DH) is a response to a stimulus that would not usually cause pain in a healthy tooth. It is characterized by sharp pain of short duration from the denuded dentin. Its etiology is unknown. The dentin only begins to show sensitivity when exposed to the buccal environment. This exposure can result after removal of the enamel and/or dental cement, or after root denudation. Different treatments are proposed for this disorder. Materials and Methods: In this study, 25 patients, with a total number of 106 cases of DH, were treated with GaAlAs low-level laser therapy (LLLT). 65% of the teeth were premolars; 14% were incisors and molars; 6.6% were canines. The teeth were irradiated with 3 and 5 J/cm 2 for up to six sessions, with an interval of 72 h between each application, and they were evaluated initially, after each application, and at 15 and 60 days follow-up post-treatment. Results: The treatment was effective in 86.53% and 88.88% of the irradiated teeth, respectively, with the minimum and maximum energy recommended by the manufacturer. There was a statistically significant difference between DH and after a follow-up of 60 days for both groups. The difference among the energy maximum and minimum was not significant. Conclusion: The GaAlAs low-level laser was effective in reducing initial DH. A significant difference was found between initial values of hypersensitivity and after 60 days follow-up post-treatment. No significant difference was found between minimum (3 J/cm 2) and maximum (5 J/cm 2) applied energy.

Amblyomma cajennense ticks induce immediate hypersensitivity in horses and donkeys

Since host immune reaction to ticks interferes with tick-borne pathogen transmission, it is important to recognize naturally occurring tick-host immune relationships to better understand the epidemiology of such infectious diseases. Amblyomma cajennense is an important tick-borne disease vector in the Neotropical region and horses maintain it in domestic environments. In the present work intradermal testing of A. cajennense tick exposed horses and donkeys using crude tick antigens was used to evaluate the type of hypersensitivity induced by infestations. Animals sensitized by A. cajennense infestation displayed an immediate hypersensitivity reaction at the antigen inoculation site. Foals sensitized with experimental infestations and field sensitized horses presented the most intense reactions (40% of ear thickness increase). Field sensitized donkeys presented less intense reaction reaching no more than 22% of mean thickness increase. Control horses (non-sensitized) had the least intense reaction, with a peak of no more 12% of increase. The presence of a prominent immediate hypersensitivity in equids sensitized experimentally or by field infestations indicates that A. cajennense ticks induce in this host an immune response that is associated with IgE production and which is known to be inappropriate against intracellular pathogens. Differences observed between horses and donkeys are discussed.

Dentin hypersensitivity after teeth bleaching with in-office systems. randomized clinical trial

Purpose: To comparatively and prospectively compare in a randomized clinical trial, dentin hypersensitivity after treatment with three in-office bleaching systems, based on hydrogen peroxide at different concentrations, with and without light source activation. Methods: 88 individuals were included according to inclusion and exclusion criteria. Subjects were randomly divided into the following three treatment groups: Group 1 was treated with three 15-minute applications of hydrogen peroxide at 15% with titanium dioxide (Lase Peroxide Lite) that was light-activated (Light Plus Whitening Lase) with five cycles of 1 minute and 30 seconds each cycle, giving a total treatment time of 45 minutes; Group 2 was treated with three 10-minute applications of hydrogen peroxide at 35% (Lase Peroxide Sensy), activated by light (LPWL) same activation cycles than Group 1, with a total treatment time of 30 minutes; Group 3 was treated with only one application for 45 minutes of hydrogen peroxide at 35% (Whitegold Office) without light activation. Each subject underwent one session of bleaching on the anterior teeth according to the manufacturers' instructions. Dentin sensitivity was recorded with a visual analogue scale (VAS) at baseline, immediately after, and at 7 and 30 days after treatment using a stimulus of an evaporative blowing triple syringe for 3 seconds on the upper central incisors from a distance of 1 cm. A Kruskal-Wallis test followed by Mann-Whitney test was performed for statistical analysis. Results: All groups showed increased sensitivity immediately after treatment. Group 1 displayed less changes relative to baseline with no significant differences (P= 0.104). At 7 and 30 days after treatment, a comparison of VAS values indicated no significant differences between all groups (P= 0.598 and 0.489, respectively).

Hypersensitivity induced in dogs by nymphal extract of Amblyomma cajennense ticks (Acari:Ixodidae)

In general, hosts develop resistance to ticks after repeated infestations; nevertheless, several studies on naturally occurring host-tick interactions were unable to detect resistance of hosts to ticks even after repeated infestations. The purpose of this investigation was to study the type of cutaneous hypersensitivity to unfed nymphal extract of A. cajennense in dogs, which, unlike guinea pigs, do not develop resistance. A first, but no second, peak in skin reaction was observed, suggesting that cellular immunity is an important mechanism of resistance to ticks. This may partially explain why guinea pigs, but not dogs, develop resistance against ticks.

Antibody and blood leukocyte response in Rhipicephalus sanguineus (Latreille, 1806) tick-infested dogs and guinea pigs

The dog is considered to be the natural host of Rhipicephalus sanguineus and is unable to develop appreciable resistance even after repeated feedings. The guinea pig develops strong resistance after one infestation with adult ticks. Antibody (IgG) titres against tick salivary gland antigens (SGAs) and blood leukocyte numbers in dogs and guinea pigs undergoing experimental R. sanguineus tick infestations were measured to detect a possible correlation with susceptibility or resistance of hosts. Since infested dogs develop an immediate hypersensitivity reaction to R. sanguineus antigens, total and anti-R. sanguineus SGA IgE levels were also measured in this host species. IgG and IgE antibody levels were determined by an enzyme-linked immunosorbent assay (ELISA) along three consecutive infestations of both hosts. Most dogs and guinea pigs displayed low IgG levels against R. sanguineus SGAs, though marked differences in individual response were observed. Although dog's total serum IgE levels increased significantly after infestations, no change in the amount of anti-salivary gland IgE was detected. Total and differential blood cell counts were determined in dogs and guinea pigs during primary and secondary infestation. In dogs, a tertiary infestation and a subsequent higher infestation level were also evaluated. Infested dogs did not display any alteration in blood leukocyte counts throughout the experiment. Guinea pigs, on the other hand, developed a significant basophilia during primary infestation which increased further during secondary infestation. These data reveal similarities and differences in the reactions of resistant and non-resistant hosts to ticks. They contribute for the understanding of such host-parasite relationships and will hopefully aid in the development of immune control of ticks. (C) 2003 Elsevier B.V. All rights reserved.

Especificidade de Puccinia pampeana a cultivares de Capsicum spp. e outras solanáceas

A ferrugem de espécies de Capsicum spp. (pimenta e pimentão), é causada pelo fungo Puccinia pampeana, pode causar perdas totais em plantios de diversas espécies de Capsicum, onde preodminam temperaturas ao redor de 21ºC. Esta ferrugem, mesmo sendo específica do gênero Capsicum, e mesmo muitas espécies dentro deste gênero sendo suscetíveis, algumas apresentam reação de hipersensibilidade. Foi o caso de Capsicum annuum (pimenta cv. Cayenne) e C. chinense (pimenta cv. Habañero), que após a formação dos espermogônios (11 dias), apresentou manchas necróticas na região periférica aos espermogônios, aos 15 dias após a inoculação, não havendo evolução da infecção. Também foi observada reação de hipersensibilidade, de forma mais moderada em folhas C. annuum (pimenta serrano) e C. baccatum (chapéu-de-frade). Com relação às outras solanáceas inoculadas (jiló e berinjela) não foram observados os sintomas e sinais da infecção.

Experimental dermatophytosis in hamsters inoculated with Trichophyton mentagrophytes in the cheek pouch

Esse estudo apresenta os resultados obtidos quando da inoculação de Trychophyton mentagrophytes na bolsa jugal do hamster, local imunologicamente privilegiado. Foram utilizados 42 animais: 21 inoculados com 10(6) fungos na bolsa jugal (grupo 1) e, 21 inicialmente inoculados com 10(6) fungos no coxim plantar e, 15 dias após, na bolsa jugal com a mesma quantidade fúngica (grupo 2). Os animais foram sacrificados às 20 h, 3, 7, 14, 30, 60 e 120 dias; foram coletadas amostras da bolsa jugal inoculada, e das patas submetidas ao teste do coxim plantar (TCP). Independente do grupo e do tempo de evolução da infecção, os animais não desenvolveram hipersensibilidade tardia avaliada através do TCP. A pré-inoculação de fungos no coxim plantar não alterou a morfologia das lesões induzidas na bolsa jugal. Assim, nos animais do grupo 1 e grupo 2, a introdução do fungo na bolsa jugal, resultou em lesão focal, constituída por infiltrado inflamatório agudo estéril, com formação de abscesso, que evoluiu para reação macrofágica e, posteriormente, para a resolução mesmo na ausência de resposta imune detectável pelo TCP. Nossos resultados indicam que, apesar do importante papel da resposta imune na regressão espontânea da dermatofitose, outros fatores são, também, parte integral da defesa contra esta infecção fúngica.

Topical (S)-ketamine for pain management of postherpetic neuralgia

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Avaliação do estado nutricional de indivíduos adultos sadios de classe média: ingestão energética e protéica, antropometria, exames bioquímicos do sangue e testes de imunocompetência

Foram estudados parâmetros relacionados ao estado nutricional de 151 adultos sadios, pertencentes à classe média e residindo em Botucatu, SP, Brasil. Valores antropométricos foram maiores nos homens, com exceção da prega tricipital e da área adiposa do braço. O aumento da idade associou-se a aumento dos valores da massa muscular (homens e mulheres) e do peso do corpo, da prega tricipital e da área adiposa do braço (mulheres). Os resultados antropométricos aproximaram-se dos valores referenciais internacionais, mas não foram inteiramente concordantes com eles, sendo inferiores para o peso corpóreo e circunferência e área musculares do braço. Nos indivíduos de menos de 50 anos, os valores da ingestão energética foram ligeiramente inferiores aos níveis recomendados. A ingestão protéica foi adequada. Os valores médios das proteínas e lípides do soro foram similares aos valores de referência. Testes de hipersensibilidade cutânea são apresentados como uma prova funcional para avaliação do estado nutricional.

Skin reactions to drugs

OBJECTIVE - To assess drug reactions and report the drugs involved and the most frequent types of skin reactions.METHODS - A retrospective and descriptive study. Data of inpatients at the Dermatology Ward with initial diagnosis of adverse drug reactions were evaluated from January 1999 to June 2004. Patients with confirmed diagnosis were included in the study based on clinical and histopathological criteria, after analysis of medical charts.RESULTS - Initial diagnosis of adverse drug reactions was confirmed in 121 patients. Forty-three patients were included in the study; 51.2% were females and 86% were caucasians. A total of 48,8% were on one drug only. Antibiotics were the most commonly used drug (20%) and accounted for 33% of the drug eruptions. The second group comprised anti-inflammatory drugs (16 7%), followed by anticonvulsants (13%), analgesic/antipyretic (13%.) agents. Skin eruption manifested as maculopapular exanthema in 41.9% patients, erythrodermia in 25.6%, and urticaria in 23.3%.CONCLUSION - Maculopapular exanthema was the main type of skin reaction triggered by use of drugs, and these reactions were most frequently caused by antibiotics.

Inflamação de queratoses seborreicas múltiplas induzida por quimioterapia com gencitabina

São diversos e comuns os efeitos mucocutâneos dos quimioterápicos, alguns por ação citotóxica, outros por hipersensibilidade ao fármaco. Os autores relatam a ocorrência de inflamação em múltiplas queratoses seborreicas pré-existentes, após terapia citorredutora com gencitabina, em paciente sob tratamento para neoplasia de pâncreas. Discutem, ainda, a benignidade do evento e alertam para a necessidade de adequada identificação dos efeitos cutâneos decorrentes da quimioterapia sistêmica.

Optimization of a mouse immunization protocol with Paracoccidioides brasiliensis antigens

The objectives of the present study were to optimize the protocol of mouse immunization with Paracoccidioides brasiliensis antigens (Rifkind's protocol) and to test the modulation effect of cyclophosphamide (Cy) on the delayed hypersensitivity response (DHR) of immunized animals. Experiments were carried out using one to four immunizing doses of either crude particulate P. brasiliensis antigen or yeast-cell antigen, followed by DHR test four or seven days after the last immunizing dose. The data demonstrated that an immunizing dose already elicited response; higher DHR indices were obtained with two or three immunizing doses; there were no differences between DHR indices of animals challenged four or seven days after the last dose. Overall the inoculation of two or three doses of the yeast-cell antigen, which is easier to prepare, and DHR test at day 4 simplify the original Rifkind's immunization protocol and shorten the duration of the experiments. The modulation effect of Cy on DHR was assayed with administration of 2.5, 20 and 100 mg/kg weight at seven day intervals starting from day 4 prior to the first immunizing dose. Only the treatment with 2.5 mg Cy increased the DHR indices. Treatment with 100 mg Cy inhibited the DHR, whereas 20 mg Cy did not affect the DHR indices. Results suggest an immunostimulating effect of low dose of Cy on the DHR of mice immunized with P. brasiliensis antigens.

Experimental paracoccidioidomycosis in the mouse. III. Histopathological and immunological findings after intravenous infection in the presence or absence of previous immunization

Cinqüenta camundongos suíços, brancos, com quatro semanas de idade, foram inoculados com 5x10(5) formas leveduriformes, viáveis de Paracoccidiodes brasiliensis (cepa 18). Dez destes animais tinham sido previamente imunizados com antígeno particulado de P. brasiliensis, durante quatro semanas, por injeção intradérmica. Os controles consistiram de 10 animais que foram somente imunizados e 10 inoculados com solução salina estéril. Os animais foram sacrificados após 2, 4, 7, 11 e 16 semanas. Estudamos: 1) resposta de hipersensibilidade retardada medida pelo teste do coxim plantar, 24 horas antes do sacrifício; 2) anticorpo- gênese específica avaliada pelo teste de imunodifusão dupla em gel de ágar; 3) histopatologia dos pulmões, fígado, baço, supra-renal e rins. Observamos: 1) os animais imunizados desenvolveram resposta imunecelular mais intensa que os infectados; 2) a infecção deprimiu a resposta imunecelular dos animais imunizados; 3) a histopatologia da infecção endovenosa revelou inflamação granulomatosa sistêmica e progressiva. Os animais infectados após imunização prévia apresentaram inflamação pulmonar menos extensa, com granulomas menores e com reduzido número de fungos. O presente modelo murino de paracoccidioidomicose mimetiza alguns achados da forma humana subaguda da micose (doença sistêmica com depressão da imunidade celular). O esquema de imunização extrapulmonar utilizado foi capaz de induzir certo grau de proteção do pulmão contra um desafio infeccioso pelo P. brasiliensis.

Effect of vaccination and the immunomodulators bacillus of Calmette-Guerin, Avridine and Propionibacterium acnes on rabies in mice

Responses: of vaccination and treatment to immunomodulators against rabies in mice were evaluated through macrophage inhibition factor (MIF), intra-pad inoculation (IPI) and serum neutralization (SN) tests and by the detection of gamma-interferon (IFN-gamma). Onco-BCG, Avridine and Propionibacterium acnes were administered to groups of mice. Higher survival rates were found in animals treated with P. acnes. Lower levels of IFN-gamma were observed in the groups of infected and vaccinated mice. The IPI was not effective on detecting the response of delayed-type hypersensitivity. Vaccine induced in the infected animals a more intense response to MIF reaction. (C) 1998 Elsevier B.V. Ltd. All rights reserved.