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This work presents the optimization of a sample preparation procedure using microwave-assisted digestion for the determination of nickel and vanadium in crude oil employing inductively coupled plasma optical emission spectrometry (ICP OES). The optimization step was performed utilizing a two-level full factorial design involving the following factors: concentrated nitric acid and hydrogen peroxide volumes, and microwave-assisted digestion temperature. Nickel and vanadium concentrations were used as responses. Additionally, a multiple response based on the normalization of the concentrations by the highest values was built to establish a compromise condition between the two analytes. A Doehlert matrix optimized the instrumental conditions of the ICP OE spectrometer. In this design, the plasma robustness was used as chemometric response. The experiments were performed using a digested oil sample solution doped with magnesium(II) ions, as well as a standard magnesium solution. The optimized method allows for the determination of nickel and vanadium with quantification limits of 0.79 and 0.20µgg-1, respectively, for a digested sample mass of 0.1g. The precision (expressed as relative standard deviations) was determined using five replicates of two oil samples and the results obtained were 1.63% and 3.67% for nickel and 0.42% and 4.64% for vanadium. Bismuth and yttrium were also tested as internal standards, and the results demonstrate that yttrium allows for a better precision for the method. The accuracy was confirmed by the analysis of the certified reference material trace element in fuel oil (CRM NIST 1634c). The proposed method was applied for the determination of nickel and vanadium in five crude oil samples from Brazilian Basins. The metal concentrations found varied from 7.30 to 33.21µgg-1 for nickel and from 0.63 to 19.42µgg-1 for vanadium.

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BACKGROUND: Dermatophytoses are skin superficial mycoses in which clinical manifestations are directly related to the virulence of the infecting microorganism or the host immunity. CASE REPORT: We describe a severe case of dermatophytosis associated with exfoliative erythroderma, substantial palmoplantar keratoderma, onychodystrophy affecting all nails, diffuse non-scarring alopecia and tissue fungal invasion by Trichophyton tonsurans, which led us to the diagnosis of AIDS. Direct examination and culture for fungi from skin scraping from two different sites were performed. Biopsy and histopathological exam were also performed on three different sites. Direct examination of the lesions' scraping revealed septate hyaline hyphae and arthroconidia, identified as Trichophyton tonsurans by culture in glucose Sabouraud agar and Mycosel agar. A scalp biopsy revealed follicular fungal invasion and Majocchi's granuloma. Due to the severity of the presentation we requested an anti-HIV serology, which was positive. The patient was treated with itraconazole, 200mg/day, for 120 days, which promoted a complete regression of the lesions. CONCLUSIONS: Severe and atypical forms of dermatophytosis could lead to a diagnosis of AIDS.

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The hydatid fluid (HF) that fills Echinococcus multilocularis metacestode vesicles is a complex mixture of proteins from both parasite and host origin. Here, a LC-MS/MS approach was used to compare the HF composition of E. multilocularis H95 and G8065 isolates (EmH95 and EmG8065, respectively), which present differences in terms of growth and fertility. Overall, 446 unique proteins were identified, 392 of which (88%) were from parasite origin and 54 from culture medium. At least 256 of parasite proteins were sample exclusive, and 82 of the 136 shared proteins presented differential abundance between E. multilocularis isolates. The parasite's protein repertoires in EmH95 and EmG8065 HF samples presented qualitative and quantitative differences involving antigens, signaling proteins, proteolytic enzymes, protease inhibitors and chaperones, highlighting intraspecific singularities that could be correlated to biological features of each isolate. The repertoire of medium proteins found in the HF was also differential between isolates, and the relevance of the HF exogenous protein content for the parasite's biology is discussed. The repertoires of identified proteins also provided potential molecular markers for important biological features, such as parasite growth rate and fertility, as well potential protein targets for the development of novel diagnostic and treatment strategies for alveolar echinococcosis. BIOLOGICAL SIGNIFICANCE: E. multilocularis metacestode infection of mammal hosts involve complex interactions mediated by excretory/secretory (ES) products. The hydatid fluid (HF) that fills the E. multilocularis metacestode vesicles contains complex repertoires of parasite ES products and host proteins that mediate important molecular interactions determinant for parasite survival and development, and, consequently, to the infection outcome. HF has been also extensively reported as the main source of proteins for the immunodiagnosis of echinococcosis. The performed proteomic analysis provided a comprehensive profiling of the HF protein composition of two E. multilocularis isolates. This allowed us to identify proteins of both parasite and exogenous (medium) origin, many of which present significant differential abundances between parasite isolates and may correlate to their differential biological features, including fertility and growth rate.

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Halogens in the atmosphere play an important role in climate change and also represent a potential health hazard. However, quantification of halogens is not a trivial task, and methods that require minimum sample preparation are interesting alternatives. Hence, the aim of this work was to evaluate the feasibility of direct solid sample analysis using high-resolution continuum source molecular absorption spectrometry (HR-CS MAS) for F determination and electrothermal vaporization-inductively coupled plasma mass spectrometry (ETV-ICP-MS) for simultaneous Cl, Br, and I determination in airborne inhalable particulate matter (PM10) collected in the metropolitan area of Aracaju, Sergipe, Brazil. Analysis using HR-CS MAS was accomplished by monitoring the CaF molecule, which was generated at high temperatures in the graphite furnace after the addition of Ca. Analysis using ETV-ICP-MS was carried out using Ca as chemical modifier/aerosol carrier in order to avoid losses of Cl, Br, and I during the pyrolysis step, with concomitant use of Pd as a permanent modifier. The direct analysis approach resulted in LODs that were proven adequate for halogen determination in PM10, using either standard addition calibration or calibration against a certified reference material. The method allowed the quantification of the halogens in 14 PM10 samples collected in a northeastern coastal city in Brazil. The results demonstrated variations of halogen content according to meteorological conditions, particularly related to rainfall, humidity, and sunlight irradiation.

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Sporotrichosis is an implantation mycosis caused by pathogenic species of Sporothrix schenckii complex that affects humans and animals, especially cats. Its main forms of zoonotic transmission include scratching, biting and/or contact with the exudate from lesions of sick cats. In Brazil, epidemic involving humans, dogs and cats has occurred since 1998. The definitive diagnosis of sporotrichosis is obtained by the isolation of the fungus in culture; however, the result can take up to four weeks, which may delay the beginning of antifungal treatment in some cases. Cytopathological examination is often used in feline sporotrichosis diagnosis, but accuracy parameters have not been established yet. The aim of this study was to evaluate the accuracy and reliability of cytopathological examination in the diagnosis of feline sporotrichosis. The present study included 244 cats from the metropolitan region of Rio de Janeiro, mostly males in reproductive age with three or more lesions in non-adjacent anatomical places. To evaluate the inter-observer reliability, two different observers performed the microscopic examination of the slides blindly. Test sensitivity was 84.9%. The values of positive predictive value, negative predictive value, positive likelihood ratio, negative likelihood ratio and accuracy were 86.0, 24.4, 2.02, 0.26 and 82.8%, respectively. The reliability between the two observers was considered substantial. We conclude that the cytopathological examination is a sensitive, rapid and practical method to be used in feline sporotrichosis diagnosis in outbreaks of this mycosis.

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Three families of New World monkeys, the Pitheciidae, Atelidae, and Cebidae, are currently recognized. The monophyly of the Cebidae is supported unequivocally by the presence of ten unique Alu elements, which are absent from the other two families. In this paper, the five genomic regions containing these Alu elements were sequenced in specimens representing nine capuchin (Cebus, Sapajus) species in order to identify mutations that may help elucidate the taxonomy and phylogenetic relationships of the cebids. The results confirmed the presence of previously described Alu elements in the capuchins. An Alu insertion present in the Cebidae2 genomic region belonging to the AluSc subfamily was amplified and sequenced only in Sapajus. No amplified or unspecific product was obtained for all other species studied here. An AluSc insertion present in the CeSa1 region was found only in Cebus, Sapajus, and Saimiri. Cebidae4 was characterized by two insertions, an AluSz6 shared by all cebids, and a complete SINE (AluSx3) found only in the capuchins (Cebus and Sapajus). The genomic region Cebidae5 revealed two insertion events, one of the AluSx subfamily, which was shared by all cebids, and another (AluSc8), that was unique to Cebus, offering a straightforward criterion for the differentiation of the two genera, Cebus and Sapajus. The Cebidae6 region showed four distinct insertion events: a 52-bp simple repeat ((TATG) n), two very ancient repeats (MIRc) and a TcMar-Tigger shared by all New World monkeys studied so far, and an Alu insertion of the AluSx subfamily present exclusively in the cebids. The phylogenetic tree confirmed the division of the capuchins into two genera, Cebus and Sapajus, and suggested the southern species Sapajus nigritus robustus and S. cay as the earliest and second earliest offshoots in this genus, respectively. This supports a southern origin for the Sapajus radiation.

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BACKGROUND: Volatile oils from fresh roots, stems, leaves and seeds of Piper klotzschianum (Piperaceae) were obtained by hydrodistillation and analysed by GC-FID and GC-MS. In total, 25 components, representing more than 95% of the examined oils, were identified. The essential oils were evaluated against Artemia salina Leach nauplii and fourth-instar Aedes aegypti larvae. RESULTS: The major chemical constituents that were identified from various parts of this plant were 1-butyl-3,4-methylenedioxybenzene and 2,4,5-trimethoxy-1-propenylbenzene in the root, 1-butyl-3,4-methylenedioxybenzene in the stems and leaves and 1-butyl-3,4-methylenedioxybenzene, limonene and α-phellandrene in the seeds. The biological activities of these essential oils generally exhibited high toxicity against A. salina, with LC50 values that ranged from 7.06 to 15.43 µg mL(-1), and significant larvicidal activity against fourth-instar A. aegypti larvae was observed in the essential oils from the seeds (LC50 of 13.27 µg mL(-1)) and roots (LC50 of 10.0 µg mL(-1)) of the plant. CONCLUSION: The present study indicates that both essential oil of P. klotzsdhianum and the isolate 1-butyl-3,4-methylenedioxybenzene are potential resources for A. aegypti larva control. This is the first report of the biological activities of the oil and isolated compound.

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This work describes the chemical composition and antimicrobial activity of the volatile oils of Ocimum canum and Ocimum selloi, both occurring in Jequié/BA, northeastern Brazil. The plants were collected in the winter/2005 and summer/2006, the oils extracted by steam distillation and further analyzed by GC-MS. A total of 30 and 31 compounds was identified from the oils of O. selloi and O. canum, respectively. It was observed that the oil content of O. canum showed variation during the seasons, while the oils of O. selloi did not. Methylchavicol and linalool were the main chemical components found in the aerial parts and leaves of O. canum. This finding permitted to characterize this specimen as a new chemotype of O. canum. Regarding the aerial parts of O. selloi, eugenol, 1,8-cineole, transcaryophyllene and linalool were identified as their major components. All extracted oils from the aerial parts showed biological activity against gram-positive cocci ­ Staphylococcus aureus ATCC 25923 ­ but only the O. canum one showed activity against gram-negative bacilli ­ Escherichia coli ATCC 25922.

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This work describes the chemical composition and antimicrobial activity of the volatile oils of Ocimum canum and Ocimum selloi, both occurring in Jequié/BA, northeastern Brazil. The plants were collected in the winter/2005 andsummer/2006, the oils extracted by steam distillation and further analyzed by GC-MS. A total of 30 and 31 compounds was identified from the oils of O. selloi and O. canum, respectively. It was observed that the oil content of O. canum showed variation during the seasons, while the oils of O. selloi did not. Methylchavicol and linalool were the main chemical components found in the aerial parts and leaves of O. canum. This finding permitted to characterize this specimen as a new chemotype of O. canum. Regarding the aerial parts of O. selloi, eugenol, 1,8-cineole, transcaryophyllene and linalool were identified as their major components. All extracted oils from the aerial parts showed biological activity against gram-positive cocci - Staphylococcus aureus ATCC 25923 - but only the O. canum one showed activity against gram-negative bacilli - Escherichia coli ATCC 25922.

Este trabalho descreve a composição química e a atividade antimicrobiana dos óleos voláteis de Ocimum canum e Ocimum selloi, que ocorrem em Jequié/BA, nordeste do Brasil. As plantas foram colhidas no inverno de 2005 e verão de 2006 e os óleos extraídos por destilação a vapor foram posteriormente analisados por GC-MS. Um total de 30 e 31 compostos foi identificado a partir dos óleos de O. selloi e O. canum, respectivamente. Foi observado que o teor de óleo de O. canum apresentou variação durante as estações do ano, enquanto o óleo de O. selloi não. Metilchavicol e linalol foram os principais componentes químicos encontrados na parte aérea e folhas de O. canum. Esta descoberta permitiu caracterizar este espécime como um novo quimiotipo de O. canum. Com relação às partes aéreas de O. selloi, eugenol, 1,8-cineol, trans-cariofileno e linalol foram identificadas como os seus principais componentes. Todos os óleos extraídos das partes aéreas apresentaram atividade biológica contra cocos gram-positivo - Staphylococcus aureus ATCC 25923 - mas apenas aquele de O. canum apresentou atividade contra bacilo gram-negativo - Escherichia coli ATCC 25922.

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Um total de 56 crianças com diagnóstico de otite média aguda (exame clínico, otoscopia e timpanometria) foram tratadas aleatoriamente com cefixima (27 casos), na dose de 8mg/Kg/dia de 24/24 horas, ou amoxicilina/clavulanato (29 casos), na dose de 25-50mg/Kg/dia de 8/8 horas, durante 5 a 10 dias, de acordo com a evolução do quadro clínico. A eficácia clínica (cura ou melhora) foi de 92,6 por cento no grupo da cefixima e 82,8 por cento no grupo da amoxicilina/clavulanato (p>0,82). A tolerabilidade foi considerada boa em 23 pacientes (85,2 por cento) e 20 pacientes (69 por cento), respectivamente (p>0,29). A aderência ao tratamento foi de 96,3 por cento no grupo cefixima e de 65,5 por cento no grupo amoxicilina/clavulanato (p<0,004)

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