Standardization and Prevalence of the Booster Phenomenon: Evaluation Using a Two-Step Skin Test with 43 kDa Glycoprotein in Individuals from an Endemic Region of Paracoccidioidomycosis.

BACKGROUND: We estimated the occurrence rate of the booster phenomenon by using an intradermal test with 43 kDa glycoprotein in an endemic area of paracoccidioidomycosis in the central-west region of Brazil. METHODS: Individuals who had a negative result on a survey performed by using an intradermal test with 43 kDa glycoprotein in an endemic area of paracoccidioidomycosis underwent a second intradermal test after 10-15 days to determine the presence or absence of the booster phenomenon. Statistical analyses were performed using the Chi-square test, Chi-square for linear trend test, Student's t test, and binomial test; p < 0.05 was considered significant. RESULTS: For the first time, we reported the occurrence of the booster phenomenon to an intradermal reaction caused by 43 kDa glycoprotein at a rate of 5.8-8.4%, depending on the test's cutoff point. This suggests that a cutoff point should be considered for the booster phenomenon in intradermal tests with 43 kDa glycoprotein: a difference of 6-7 mm between readings according to the first and second tests, depending on the purpose of the evaluation. CONCLUSION: The results indicate that the prevalence of paracoccidioidal infection in endemic areas is underestimated, as the booster phenomenon has not been considered in epidemiological surveys for this infection.

Evaluation of Paracoccidioides brasiliensis infection by gp 43 intradermal test in rural settlements in Central-West Brazil.

Epidemiological studies of paracoccidioidomycosis have been based on surveys achieved with intradermal tests, and paracoccidioidin is the most common antigen used in most cases. The glycoprotein of 43-kDa (gp43) has been used in intradermal tests. It is the most antigenic component of Paracoccidioides brasiliensis, and it provides greater specificity to evaluate infection for this fungus. In this study, the prevalence of P. brasiliensis infection was estimated with intradermal tests involving gp43 for 695 people in rural Central-West Brazil. The infection rate was 45.8 % (95 % CI = 42.1-49.5), and the average age of those infected was 45.8 ± 18.2 years. The prevalence did not show gender-based differences but increased with age. The results demonstrate the importance of P. brasiliensis infection in rural settlements and the early exposure of children in the region to the fungus. Despite the high antigenicity and specificity of gp43, its usage must be standardized, so that epidemiological surveys will be comparable and more accurately reflect P. brasiliensis infection in endemic areas.

Interleukin-12 response to NcSRS2 immunization of BALB/c mice against Neospora caninum.

The apicomplexan parasite Neospora caninum can cause abortions and is recognized as an important causative agent responsible for economic and reproductive losses in the cattle industry. Humoral immune response was investigated in BALB/c mice by using recombinant NcSRS2 expressed in Escherichia coli as polyhistidine-tagged fusion proteins. NcSRS2 is the major immunodominant tachyzoite surface antigen of N. caninum. Separate groups of female BALB/c mice were infected subcutaneously with (P) PBS, (N) recNcSRS2, (NIL) recNcSRS2 plus interleukin-12 or (NF) recNcSRS2, in Freunds adjuvant. Serological analysis showed that the antibodies produced by immunization recognized native protein from N. caninum tachyzoites and that, 14 days after the initial immunization, NcSRS2-specific antibodies were present in all sera tested from the groups N, NIL and NF. NcSRS2 with Freuds adjuvant led to a stronger immune response, as measured by IgG1 and IgG2a levels, than did other formulations (NF > NIL > N > P; p < 0.001), with a Th2 bias. The results corroborate the potential use of recombinant protein NcSRS2 as a vaccine aimed at reducing congenital transmission. Further studies are required to identify new adjuvants capable of improving the induction of Th1 immune response.

Anatomia cirúrgica do ramo externo do nervo laríngeo superior / Surgical anatomy of the external branch of the superior laryngeal nerve

Introdução: o ramo externo do nervo laríngeo superior (RELS) é um ramo motor que tem origem no nível do osso hióide e desce medialmente à artéria carótida interna para inervar o músculo cricotireóideo da laringe. Nesse trajeto, aproxima-se do pólo superior da glândula tireóide. Muitos estudos têm sido feitos com o objetivo de avaliar a necessidade e viabilidade técnica de sua identificação durante operações sobre a glândula, mas alguns com resultados adversos. Objetivo: estudar a relação anatômica entre o RELS, a tireóide e a artéria tireoidiana superior e a viabilidade técnica e o tempo despendido em sua identificação durante procedimentos cirúrgicos sobre a glândula tireóide. Pacientes e método: foram estudados 40 RELS em pacientes que se submeteram a tireoidectomia por bócios nodulares, bócio difuso tóxico e câncer de tireóide. Foi analisado o tipo de disposição do nervo em relação à glândula tireóide e artéria tireoideana superior; a viabilidade de sua identificação durante a operação; e o tempo despendido para isso. Resultados: em mais da metade dos pacientes o RELS está a menos de 1,0cm da glândula e, em 62,5% dos casos, o nervo foi devidamente identificado em menos de quatro minutos. Conclusão: o RELS está muito próximo do pólo superior do lobo tireoideano; sua identificação cuidadosa é viável; e não acrescenta tempo significativo à cirurgia, devendo ser realizada sempre, para diminuir a morbidade da operação.

Introduction: the external branch of the superior laryngeal nerve (EBSL) is a motor branch that begins near the hyoid bone, than it goes down between the internal carotid artery and the larynx, and finds the cricothyroid muscle. In the way to the muscle, the nerve crosses the superior pole of the thyroid lobe. Many studies have been performed in order to observe the technical viability of finding the nerve during the thyroid surgery, and if we have to do it. There is some disagreement about this point. Objective: to study the anatomical relationship among the EBSL, the thyroid gland and the superior thyroid artery and the technical availability and the time spent in that identification during the surgical approach on the gland. Materials and methods: 40 EBLS were studied in patients who had the thyroid operated. These people had nodular goiter, toxic diffuse goiter, follicular adenoma or thyroid cancer. The anatomical relationship among the nerve, thyroid gland and superior thyroid artery were studied; as well as the viability of the nerve identification and the time spent to do it. Results: the nerve was near the superior pole of the lobe of the thyroid gland in 52.5% of cases; it was spent less than 4 minutes to find the EBSL in 62.5% of patients. Conclusion: the nerve is frequently very close to the gland, and its identification, which is possible in a few minuts, is recommended during thyroid surgery to avoid nerve damage.

Pesticides exposure in Culturama, Brazil--knowledge, attitudes, and practices.

In this study, the knowledge, attitudes, and practices associated with pesticide use and exposure were evaluated in the agricultural community of Culturama, in the state of Mato Grosso do Sul, Brazil. A standardized questionnaire was completed by 250 farm workers aged > or =18 years old. The average age of the studied population was 43.6 years and 17.6% had never been to school. Their farms were small (approximately 30ha) and family operated and did not utilize advanced farming technology. About 92% of the interviewees had worked directly with pesticides and 59.6% reported typical intoxication symptoms. Only 44.3%, however, believe that they had been intoxicated. A significant correlation was found between hand washing after pesticide application and reporting symptoms (P=0.014). Over 90% of the farmers reported using the organophosphorus insecticide methamidophos. A great majority (>90%) considered pesticides to be harmful to human health, but less than 20% used masks, impermeable clothes, or gloves during pesticide application. These results indicate that special educational programs, legislation promoting the use of safer pesticides, and implementation of personal protective measures are necessary to decrease the pesticide exposure of farmers in Culturama.