Rinoscopia como auxiliar no diagnóstico de criptococose felina: Relato de caso / Rhinoscopy as aid in the diagnosis of feline cryptococosis: case report

Criptococose é uma micose sistêmica não contagiosa que acomete, principalmente, felinos. O agente etiológico é uma levedura do gênero Cryptococcus sp., e a sua transmissão ocorre por via aerógena, com a inalação dos esporos que se alojam, principalmente, na cavidade nasal e pulmão. A forma nasal é a mais comum em felinos e as suas manifestações clínicas incluem edema nasofacial, eritema e secreção nasal. O diagnóstico pode ser realizado por meio de cultivo micológico, citologia, histologia e reação em cadeia polimerase. Neste artigo, é apresentado o relato de caso de um felino diagnosticado com criptococose, no qual o diagnóstico de triagem foi realizado por meio de rinoscopia. No atendimento inicial, o animal apresentava hiporexia, reflexo de deglutição constante, engasgos, odor acentuado em região nasal e crepitações pulmonares com evolução de três meses. O diagnóstico foi realizado com o emprego de rinoscopia, que identificou massa interna na região da mucosa nasofaríngea, com posterior biópsia e exame anatomopatológico. Após a confirmação diagnóstica, o paciente foi medicado com itraconazol 10 mg/kg SID, por 5 meses, e teve a resolução de todos os sinais clínicos apresentados. A criptococose deve ser considerada como diagnóstico, diferencial de alterações do sistema respiratório em felinos e a rinoscopia pode ser um recurso diagnóstico importante para auxiliar na conclusão e reconhecimento da enfermidade.(AU)

Cryptococcosis is a non-contagious systemic mycosis that primarily affects felines. Its etiological agent is a yeast of the genus Cryptococcus sp., and its transmission occurs through the air, by inhalation of spores that primarily lodge in the nasal cavity and lungs. The nasal form is the most common in felines and clinical manifestations include nasofacial edema, erythema and nasal discharge. Diagnosis can be made by means of mycological culture, cytology, histology and polymerase chain reaction. This article presents a case of a feline diagnosed with cryptococcosis, in which the screening diagnosis was performed by means of rhinoscopy. In the initial care, the animal presented hyporexia, constant swallowing reflex, choking, accentuated odor in the nasal region and pulmonary crackles with evolution of three months. The diagnosis was made using rhinoscopy, which identified an internal mass in the nasopharyngeal mucosa, and subsequent biopsy and anatomopathological examination. After diagnostic confirmation, the patient was medicated with itraconazole 10 mg/kg SID for 5 months and had resolution of all clinical signs presented. Cryptococcosis should be considered as a differential diagnosis of alterations in the respiratory system in cats and rhinoscopy can be an important diagnostic tool to assist in the conclusion and recognition of this disease.(AU)

Tratamento de efluentes na piscicultura com ênfase em tratamentos sustentáveis / Treatment of effluents in pisciculture with emphasis on sustainable treatments

O objetivo desse trabalho foi realizar revisão bibliográfica de caráter exploratório sobre tratamento de efluentes na piscicultura com ênfase nos tratamentos sustentáveis e seu impacto ecológico. A importância deste tema envolve pesquisar métodos de tratamentos alternativos aos dejetos da piscicultura, visto sua importância referente à sustentabilidade. Além disso, há tendência mundial da população buscar hábitos alimentares saudáveis, que gerem menor impacto ao meio ambiente, influenciando diretamente no desenvolvimento agropecuário. A proposta de tratamento de efluentes na piscicultura por métodos alternativos visa a diminuição de poluentes na água, considerando técnicas já utilizadas em saneamento básico, aplicadas com os efluentes da aquicultura. No Brasil, utiliza-se o método de processos oxidativos avançados ­ POA por cloro, que ao reagir com outros compostos, libera substâncias contaminantes ao meio ambiente. De um modo geral, a piscicultura produz baixo impacto ambiental e à saúde humana, mas é importante enfatizar a relação única de saúde na produção de alimentos.(AU)

The objective of this work was to carry out an exploratory literature review on effluent treatment in fish farming with an emphasis on sustainable treatments and their ecological impact. The importance of this theme involves researching alternative treatment methods to fish farming waste, given its importance in terms of sustainability. In addition, there is a global tendency of the population to seek healthy eating habits, which generate less impact on the environment, directly influencing agricultural development. The proposed treatment of effluents in fish farming by alternative methods aims to reduce pollutants in the water, considering techniques already used in basic sanitation, applied with effluents from aquaculture. In Brazil, advanced oxidative processes are used ­ POA's by chlorine, which when reacting with other compounds, releases contaminant substances into the environment. In general, fish farming has a low impact on the environment and human health, but it is important to emphasize the unique relationship of health in food production.(AU)

Expression of Genes by Aflatoxigenic and Nonaflatoxigenic Strains of Aspergillus flavus Isolated from Brazil Nuts.

The aims of the present study were to monitor the production of aflatoxin B1 (AFB1) and mycelial growth, and to evaluate the expression of genes directly and indirectly involved in the biosynthesis of aflatoxins by Aspergillus flavus isolated from Brazil nuts. Six previously identified A. flavus strains were grown on coconut agar at 25°C for up to 10 days. Mycotoxins were separated by high-performance liquid chromatography and fungal growth was measured daily using the diametric mycelial growth rate. Transcriptional analysis was performed by real-time polymerase chain reaction (PCR) after 2 and 7 d of incubation using specific primers (aflR, aflD, aflP, lipase, metalloprotease, and LaeA). Three (50%) of the six A. flavus isolates produced AFB1 (ICB-1, ICB-12, and ICB-54) and three (50%) were not aflatoxigenic (ICB-141, ICB-161, and ICB-198). Aflatoxin production was observed from d 2 of incubation (1.5 ng/g for ICB-54) and increased gradually with time of incubation until d 10 (15,803.6 ng/g for ICB-54). Almost all A. flavus isolates exhibited a similar gene expression pattern after 2 d of incubation (p > 0.10). After 7 d of incubation, the LaeA (p < 0.05) and metalloprotease (p < 0.05) genes were the most expressed by nonaflatoxigenic strains, whereas aflatoxigenic isolates exhibited higher expression of the aflR (p < 0.05) and aflD genes (p < 0.05). Our results suggest that the expression of aflR and aflD is correlated with aflatoxin production in A. flavus and that overexpression of aflR could affect the transcriptional and aflatoxigenic pattern (ICB-54). Elucidation of the molecular mechanisms that regulate the secondary metabolism of toxigenic fungi may permit the rational silencing of the genes involved and consequently the programmed inhibition of aflatoxin production. Knowledge of the conditions, under which aflatoxin genes are expressed, should contribute to the development of innovative and more cost-effective strategies to reduce and prevent aflatoxin contamination in Brazil nuts.

Molecular and mycotoxigenic biodiversity of Aspergillus flavus isolated from Brazil nuts.

The objective of this study was to carry out a transcription analysis of eight genes belonging to the aflatoxin (AF) and cyclopiazonic acid (CPA) biosynthesis pathway, and to detect aflatoxin B1 (AFB1) and CPA production in Aspergillus flavus strains isolated from Brazil nuts. Additionally, these genes were correlated with the different mycotoxigenic profiles of the same strains. Four previously identified A. flavus strains (ICB-01, ICB-151, ICB-161, and ICB-165) were grown on Brazil nut agar at 25°C for 10days. Mycotoxins were separated by high-performance liquid chromatography. Transcriptional analysis was performed by real-time RT-PCR using specific primers designed based on the conserved regions of two regulatory genes (aflR and aflS), three structural genes of the AFB1 biosynthesis pathway (aflH, aflJ and aflP), and three structural genes of the CPA biosynthesis pathway (maoA, dmaT and pks-nrps). The expression of most genes in the A. flavus isolates varied according to the mycotoxin profile of each strain. The most expressed genes in the aflatoxigenic strain ICB-151 were aflJ (77.11%) and aflH (32.75%), while the CPA-producing strain ICB-161 mainly expressed dmaT (100%), maoA (63.72%), aflS (43.52%), and aflR (42.63%). The ICB-01 isolate was a producer of AFB1 and CPA and the most expressed genes were aflS (47.79%), dmaT (42.77%), aflP (39.5%), and aflR (38.02%). ICB-198 did not produce any mycotoxin and exhibited lower expression of almost all genes analyzed. Furthermore, the ratio of aflS/aflR expression was correlated with the biosynthesis of AF and CPA in A. flavus strains producing exclusively AF or CPA or producing both AF and CPA. The ratio of aflS/aflR expression therefore seems to be related to the production of mycotoxins in Brazil nuts. Our results provide important data for the development of innovative and more cost-effective strategies to reduce and prevent AFB and CPA contamination in Brazil nuts.

Effects of Gamma and Electron Beam Radiation on Brazil Nuts Artificially Inoculated with Aspergillus flavus.

The aim of this study was to evaluate the effects of gamma radiation (GR) and electron beam (EB) on Brazil nut samples contaminated with Aspergillus flavus. Fifty samples were spread with an A. flavus suspension and incubated at 30°C and a relative humidity of 93%. After 15 days of incubation, mycobiota and aflatoxin analysis were performed. The samples were divided into three groups (control, group 1, and group 2) that received radiation doses of 0 kGy (control) and 5 and 10 kGy each of GR and EB (groups 1 and 2). Noninoculated samples were irradiated with the same doses for sensory evaluation. The results showed that after 15 days of incubation, the average water activity of the samples was 0.80. The irradiation with GR and EB at doses of 5 and 10 kGy was able to eliminate A. flavus in Brazil nut samples. Aflatoxin analysis showed that EB doses of 5 and 10 kGy reduced aflatoxin B1 levels by 53.32 and 65.66%, respectively, whereas the same doses of GR reduced the levels of this toxin by 70.61 and 84.15% compared with the level in the control groups. Sensory evaluation demonstrated that the texture and odor of irradiated Brazil nut samples were acceptable. The taste evaluation indicated that 5 kGy of GR was judged acceptable. The results highlight that both irradiation processes (5- and 10-kGy doses) showed efficiency in A. flavus and aflatoxin elimination. GR and EB treatments resulted in some alterations in the sensory attributes of samples with the doses used in this study; however, Brazil nut samples irradiated with 5-kGy GR doses were considered acceptable.

Monitoring and determination of fungi and mycotoxins in stored Brazil nuts.

Brazil nut (Bertholletia excelsa) is an important commodity from the Brazilian Amazon, and approximately 37,000 tons (3.36 × 107 kg) of Brazil nuts are harvested each year. However, substantial nut contamination by Aspergillus section Flavi occurs, with subsequent production of mycotoxins. In this context, the objective of the present investigation was to evaluate the presence of fungi and mycotoxins (aflatoxins and cyclopiazonic acid) in 110 stored samples of cultivated Brazil nut (55 samples of nuts and 55 samples of shells) collected monthly for 11 months in Itacoatiara, State of Amazonas, Brazil. The samples were inoculated in duplicate onto Aspergillus flavus and Aspergillus parasiticus agar and potato dextrose agar for the detection of fungi, and the presence of mycotoxins was determined by high-performance liquid chromatography. The most prevalent fungi in nuts and shells were Aspergillus spp., Fusarium spp., and Penicillium spp. A polyphasic approach was used for identification of Aspergillus species. Aflatoxins and cyclopiazonic acid were not detected in any of the samples analyzed. The low water activity of the substrate was a determinant factor for the presence of fungi and the absence of aflatoxin in Brazil nut samples. The high frequency of isolation of aflatoxigenic Aspergillus section Flavi strains, mainly A. flavus, and their persistence during storage increase the chances of aflatoxin production on these substrates and indicates the need for good management practices to prevent mycotoxin contamination in Brazil nuts.

Polyphasic approach to the identification of Aspergillus section Flavi isolated from Brazil nuts.

The aim of this study was to use a polyphasic approach to identify Aspergillus section Flavi isolated from Brazil nuts collected in the Amazon forest: investigation of macro- and microscopic morphology, production of extrolites, heat-resistance fungi, and sequencing of DNA regions. The following Aspergillus section Flavi species were identified: Aspergillus flavus (75.5%), Aspergillus nomius (22.3%), and Aspergillus parasiticus (2.2%). All A. nomius and A. parasiticus isolates produced aflatoxins B and G, but not cyclopiazonic acid (CPA). A. flavus isolates were more diversified and a high frequency of mycotoxigenic strains was observed. The polyphasic approach permitted the reliable identification of section Flavi species. The rate of mycotoxigenic strains was high (92.7%) and mainly included A. flavus strains producing elevated levels of aflatoxins and CPA. These results highlight the possibility of co-occurrence of both toxins, increasing their potential toxic effect in this commodity.