Air fungal contamination in two elementary schools in Lisbon, Portugal

A descriptive study was developed to monitor air fungal contamination in two elementary schools in Lisbon, Portugal. Eight air samples of 250 litres through impaction method were collected in canteen, library, classrooms and also, outside premises as reference place. Simultaneously, were also monitored environmental parameters, including temperature, and humidity through the equipment Babouc, LSI Sistems and according to the International Standard ISO 7726 - 1998. Considering both schools, sixteen different species of fungi in air were identified, being the 2 most commonly isolated Cladosporium sp. (51,1%) and Penicillium sp. (27,5%). Besides these genera Trichoderma, Aspergillus, Alternaria, Chrysonilia, Botritys, Ulocladium, Athrium, Aureobasidium, Phoma, Scedosporium e Geotrichum were also isolated. Regarding yeasts, Candida sp., Cryptococcus sp. and Rhodotorula sp. were isolated. The youngest school, as well canteens in each school, presented the worst results concerning the air fungal contamination, maybe due to the higher number of occupants. There was no significant relationship (p>0,05) between fungal contamination and temperature and humidity.

Prevalencia de microorganismos asociados a secreción genital femenina, Argentina

OBJETIVO: Hay un aumento significativo de pacientes con Secreción Genital Femenina, en el Sector Público del gran Buenos Aires. Fue necesario actualizar la prevalencia de los microorganismos asociados a los efectos de revisar el apoyo necesario de laboratorio y ajustar las medidas de prevención y control. MÉTODOS: Se incorporan a este estudio, la totalidad de los casos atendidos (1997-1998): 84 adolescentes (15 a 19 años) y 784 adultas (20 a 60 años) sintomáticas. El protocolo incluye (secreción vaginal y endocervical) detección de Neisseria gonorrhoeae, Streptococcus agalactiae, Trichomonas vaginalis, Candida spp y vaginosis bacteriana. Aplicando métodos específicos directos y cultivo, Chlamydia trachomatis (detección de antígeno), Ureaplasma urealitycum y Mycoplasma hominis (cultivos) fueron estudiados en parte de la población total. RESULTADOS: El aumento de la demanda de consulta fue continuo desde 1997 y aumentó 2.10 veces del primero al último semestre de 1998. En las mujeres adultas se encontró: vaginosis bacteriana, 23,8%; Candida spp 17,8%; S. agalactiae 5,6%; T. vaginalis 2,4%. En 50,3% no se detecto ninguno. En adolescentes se detectó: vaginosis bacteriana, 17,8%; Candida spp 29,7%; S. agalactiae 3,6%, T. vaginalis 2,4%: En 46,4% de los casos el resultado fue negativo. En el grupo de mujeres adultas sintomáticas, no en la totalidad, se detectó: C. trachomatis (7/400) 1,76%, U. urealyticum (209/340) 61,4% y M. hominis (45/272) 16,5%. CONCLUSIONES: El aumento significativo de consultas se debe a problemas sociales en la población, no al aumento de ninguna patología en especial. Impacta como problema clínico concreto la prevalencia de vaginosis bacteriana y Candida spp. Llama la atención, la nula incidencia de N. gonorrhoeae y la baja circulación de T. Vaginalis y C. trachomatis, en este tipo de población. La prevalencia de U. urealyticum y M. hominis es alta, pero su real participación en la patología genital de adultas debe ser reconsiderada. Las prevalencias establecidas motivan la necesidad de adecuar los manuales de procedimientos apuntando a la aplicación de metodologías simples de alto valor predictivo.

Bioatividade da quinoxalina 1,4-dióxido e seus derivados

O objetivo deste estudo consiste em avaliar a atividade antimicrobiana da quinoxalina 1,4-dióxido e alguns dos seus derivados em estirpes bacterianas e leveduras. Os compostos estudados foram a quinoxalina 1,4-dióxido (QNX), 2-metilquinoxalina-1,4-dióxido (2MQNX), 2-metil-3-Benzoilquinoxalina-1,4-dióxido (2M3BenzoilQNX), 2-metil-3-benzilquinoxalina-1,4-dióxido (2M3BQNX), 2-amino-3-cianoquinoxalina-1,4-dióxido (2A3CQNX), 3-metil-2-quinoxalinacarboxamida-1,4-dióxido (3M2QNXC), 2-hidroxifenazina–N-dióxido (2HF) e 3-metil-N-(2-metilphenil)quinoxalinacarboxamida-1,4-dioxido (3MN(2MF)QNXC). Os modelos procariotas selecionados para este estudo foram o Staphylococcus aureus ATCC 6538, Staphylococcus aureus ATCC 6538P, Staphylococcus aureus ATCC 29213, Escherichia coli ATCC 25922, Escherichia coli S3R9, Escherichia coli S3R22, Escherichia coli TEM CTX-M9, Escherichia coli TEM-1, Escherichia coli AmpC MOX-2, Escherichia coli CTX-M2 e Escherichia coli CTX-M9. A Candida albicans ATCC 10231 e a Saccharomyces cerevisiae PYCC 4072 constituíram os modelos eucariotas deste estudo. Para os compostos químicos que apresentem atividade pelo método de difusão em disco, será determinada a Concentração Mínima Inibitória (CMI), bem como a viabilidade e o crescimento (na presença e na ausência dos compostos químicos). Os resultados deste estudo mostram atividade antimicrobiana para a maioria dos compostos estudados em todos os modelos procariotas Gram negativos, à exceção da E.coli CTX-M2 e CTX-M9 e nenhuma atividade nos modelos eucariotas. O estudo da viabilidade/curvas de morte em bactérias e num modelo eucariota (S.cerevisiae) sugerem que alguns destes compostos constituem potenciais drogas para a quimioterapia antibacteriana.

Synthesis, Antimicrobial and Antiproliferative Activity of Novel Silver(I) Tris(pyrazolyl)methanesulfonateand 1,3,5-Triaza-7-phosphadamantane Complexes

Five new silver(I) complexes of formulas [Ag(Tpms)] (1), [Ag(Tpms)-(PPh3)] (2), [Ag(Tpms)(PCy3)] (3), [Ag(PTA)][BF4] (4), and [Ag(Tpms)(PTA)] (5) {Tpms = tris(pyrazol-1-yl)methanesulfonate, PPh3 = triphenylphosphane, PCy3 = tricyclohexylphosphane, PTA = 1,3,5-triaza-7-phosphaadamantane) have been synthesized and fully characterized by elemental analyses, H-1, C-13, and P-31 NMR, electrospray ionization mass spectrometry (ESI-MS), and IR spectroscopic techniques. The single crystal X-ray diffraction study of 3 shows the Tpms ligand acting in the N-3-facially coordinating mode, while in 2 and 5 a N2O-coordination is found, with the SO3 group bonded to silver and a pendant free pyrazolyl ring. Features of the tilting in the coordinated pyrazolyl rings in these cases suggest that this inequivalence is related with the cone angles of the phosphanes. A detailed study of antimycobacterial and antiproliferative properties of all compounds has been carried out. They were screened for their in vitro antimicrobial activities against the standard strains Enterococcus faecalis (ATCC 29922), Staphylococcus aureus (ATCC 25923), Streptococcus pneumoniae (ATCC 49619), Streptococcus pyogenes (SF37), Streptococcus sanguinis (SK36), Streptococcus mutans (UA1S9), Escherichia coli (ATCC 25922), and the fungus Candida albicans (ATCC 24443). Complexes 1-5 have been found to display effective antimicrobial activity against the series of bacteria and fungi, and some of them are potential candidates for antiseptic or disinfectant drugs. Interaction of Ag complexes with deoxyribonucleic acid (DNA) has been studied by fluorescence spectroscopic techniques, using ethidium bromide (EB) as a fluorescence probe of DNA. The decrease in the fluorescence of DNA EB system on addition of Ag complexes shows that the fluorescence quenching of DNA EB complex occurs and compound 3 is particularly active. Complexes 1-5 exhibit pronounced antiproliferative activity against human malignant melanoma (A375) with an activity often higher than that of AgNO3, which has been used as a control, following the same order of activity inhibition on DNA, i.e., 3 > 2 > 1 > 5 > AgNO3 >> 4.

Determination of chitin content in fungal cell wall: an alternative flow cytometric method

The conventional methods used to evaluate chitin content in fungi, such as biochemical assessment of glucosamine release after acid hydrolysis or epifluorescence microscopy, are low throughput, laborious, time-consuming, and cannot evaluate a large number of cells. We developed a flow cytometric assay, efficient, and fast, based on Calcofluor White staining to measure chitin content in yeast cells. A staining index was defined, its value was directly related to chitin amount and taking into consideration the different levels of autofluorecence. Twenty-two Candida spp. and four Cryptococcus neoformans clinical isolates with distinct susceptibility profiles to caspofungin were evaluated. Candida albicans clinical isolate SC5314, and isogenic strains with deletions in chitin synthase 3 (chs3Δ/chs3Δ) and genes encoding predicted Glycosyl Phosphatidyl Inositol (GPI)-anchored proteins (pga31Δ/Δ and pga62Δ/Δ), were used as controls. As expected, the wild-type strain displayed a significant higher chitin content (P < 0.001) than chs3Δ/chs3Δ and pga31Δ/Δ especially in the presence of caspofungin. Ca. parapsilosis, Ca. tropicalis, and Ca. albicans showed higher cell wall chitin content. Although no relationship between chitin content and antifungal drug susceptibility phenotype was found, an association was established between the paradoxical growth effect in the presence of high caspofungin concentrations and the chitin content. This novel flow cytometry protocol revealed to be a simple and reliable assay to estimate cell wall chitin content of fungi.

A novel flow cytometric protocol for assessment of yeast cell adhesion

Microbial adhesion is a field of recognized relevance and, as such, an impressive array of tools has been developed to understand its molecular mechanisms and ultimately for its quantification. Some of the major limitations found within these methodologies concern the incubation time, the small number of cells analyzed, and the operator's subjectivity. To overcome these aspects, we have developed a quantitative method to measure yeast cells' adhesion through flow cytometry. In this methodology, a suspension of yeast cells is mixed with green fluorescent polystyrene microspheres (uncoated or coated with host proteins). Within 2 h, an adhesion profile is obtained based on two parameters: percentage and cells-microsphere population's distribution pattern. This flow cytometry protocol represents a useful tool to quantify yeast adhesion to different substrata in a large scale, providing manifold data in a speedy and informative manner.

Monitoramento de fungos anemófilos e de leveduras em unidade hospitalar

OBJETIVO: Monitorar e caracterizar fungos anemófilos e leveduras de fontes bióticas e abióticas de uma unidade hospitalar. MÉTODOS: As coletas foram realizadas mensalmente e em dois períodos, do centro cirúrgico e unidades de terapia intensiva adulto e neonatal em hospital de Araraquara, Estado de São Paulo. Para coleta de fungos anemófilos foi utilizado amostrador tipo Andersen de simples estágio. A pesquisa de leveduras foi feita das mãos e de orofaringe de profissionais de saúde, bem como de superfícies de leitos e de maçanetas das áreas críticas. RESULTADOS: Foram recuperados do centro cirúrgico 32 gêneros de fungos anemófilos e 31 das unidades de terapia intensiva. Os gêneros mais freqüentemente isolados foram Cladophialophora spp., Fusarium spp., Penicillium spp., Chrysosporium spp. e Aspergillus spp. Durante o período de estudo, houve reforma e implantação de uma unidade dentro do hospital, que coincidiu com o aumento na contagem de colônias de Cladophialophora spp., Aspergillus spp. e Fusarium spp. Leveduras foram encontradas em 39,4% dos profissionais de saúde (16,7% das amostras dos espaços interdigitais, 12,1% do leito subungueal e 10,6% da orofaringe) e, em 44% das amostras do mobiliário, com predomínio do gênero Candida (C. albicans, C. guilliermondii, C. parapsilosis e C. lusitaniae) seguido por Trichosporon spp. CONCLUSÕES: Observou-se número relativamente elevado de fungos anemófilos (potencialmente patogênicos) em áreas especiais e níveis expressivos de leveduras em fontes bióticas e abióticas. O monitoramento microbiológico ambiental deve ser realizado, principalmente em salas especiais com pacientes imunocomprometidos, sujeitos à exposição de patógenos do meio ambiente, assim como, advindos de profissionais de saúde.

Antimicrobial and cytotoxic assessment of marine cyanobacteria - synechocystis and synechococcus

Aqueous extracts and organic solvent extracts of isolated marine cyanobacteria strains were tested for antimicrobial activity against a fungus, Gram-positive and Gram-negative bacteria and for cytotoxic activity against primary rat hepatocytes and HL-60 cells. Antimicrobial activity was based on the agar diffusion assay. Cytotoxic activity was measured by apoptotic cell death scored by cell surface evaluation and nuclear morphology. A high percentage of apoptotic cells were observed for HL-60 cells when treated with cyanobacterial organic extracts. Slight apoptotic effects were observed in primary rat hepatocytes when exposed to aqueous cyanobacterial extracts. Nine cyanobacteria strains were found to have antibiotic activity against two Gram-positive bacteria, Clavibacter michiganensis subsp. insidiosum and Cellulomonas uda. No inhibitory effects were found against the fungus Candida albicans and Gram-negative bacteria. Marine Synechocystis and Synechococcus extracts induce apoptosis in eukaryotic cells and cause inhibition of Gram-positive bacteria. The different activity in different extracts suggests different compounds with different polarities.

Antimicrobial activity of pyrazine and quinoxaline N,N’-dioxide heterocyclic compounds

The nitrogen heterocyclic organic compounds 1,4 dioxide pyrazine and quinoxaline derivatives have been widely studied due to their potential use as synthetic drugs. The thermochemical study of three N,N´-dioxides: 2,3,5-trimethylpyrazine-1,4-dioxide, tetramethylpyrazine-1,4-dioxide and 6-chloro-2,3-dimethilquinoxaline 1,4-dioxide has been recently developed in order to establish relationships among the energetical, structural and reactivity properties [4,5]. Several studies have reported their pharmacological activity, particularly as antimicrobial agents [1,2,3]. It has also been established a relation between energetical and structural properties and biological activity, once these compounds present N – oxide bonds, increasing their oxidative capacity. The present work reports the study of antimicrobial activity for those compounds against the bacteria Geobacillus stearothermophylus, Staphylococcus aureus, Streptococcus agalactiae, Escherichia coli and also against the yeasts Saccharomyces cerevisiae PYCC 4072, Candida albicans PYCC3436T, Candida tropicalis PYCC, Issatchenka Orientalis PYCC. The determination of the minimal inhibitory concentration (MIC), points to an antimicrobial activity and the preliminary results indicate that these compounds may be potential candidates as antimicrobial drugs with clinical, agriculture or food industries applications.

Antifungal activity of Imidazolidin-4-ones of the antimalarial primaquine

The 5-Isopropyl-3-[4-(6-methoxy-quinolin-8-ylamino)-pentyl]-2,2-dimethyl-imidazolidin-4-one (ValPQacet) was sinthesized through acylation of the anti-malarial primaquine with α-valine and subsequent reaction of the resulting -aminoamide with propanone (Sheme 1).Imidazolidin-4-ones of the anti malarial primaquine are being sinthesized to develop new variants in order to improve more effective treatments against malaria . Recently it has been observed that primaquine derivates could have effect in a new kind of yeast . To study the fungicidal activity against Candida albicans, Candida tropicalis, Issatchenkia orientalis, Sacharomyces cerevisae, the ValPQacet was put in the form of the hydrochloride salt. The minimal inhibitory concentration (MIC) could be determined for all yeast in the concentration range assayed. Also was determined MIC’s of primaquine hydrochloride salt for all yeast, and this shows that the parent drug is less active than our compound. Further studies are being performed to determine viability and cellular injury with this drugs.

Fungidal and bacterial activity of N,N-dimethyl-4-(2,2,2-trichloro-1-(phenylamino)ethyl)aniline

N,N-dimethyl-4-((phenylamino)methyl)aniline (1) was prepared by condensation of aniline and 4-(dimethylamino)benzaldehyde [1] N,N-dimethyl-4-(2,2,2-trichloro-1-(phenylamino)ethyl)aniline (2) was synthesized by trichloromethylation of the imine (N,N-dimethyl-4-((phenylimino)methyl)aniline (1)) with trichloroacetic anhydride under microwave irradiation [2] (Sheme 1). The present work reports the study of bacterial and yeast activity for the compound 2. The bacteria used in this study are Staphylococcus aureus, Escherichia coli and the yeast are Saccharomyces Cerevisiae Candida albican.The results that we will present are the determination of minimal inhibitory concentration (MIC), by means of microdilution by plate method and the specific growth constants for this microorganism. Further studies are being performed to determine viability and cellular injury with this drug.

Efeito da combinação de antibióticos e sinvastatina sobre microrganismos de interesse endodôntico e na expressão de marcadores odontoblásticos

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Mould and yeast identification in archival settings: preliminary results on the use of traditional methods and molecular biology options in Portuguese archives

This project was developed to fully assess the indoor air quality in archives and libraries from a fungal flora point of view. It uses classical methodologies such as traditional culture media – for the viable fungi – and modern molecular biology protocols, especially relevant to assess the non-viable fraction of the biological contaminants. Denaturing high-performance liquid chromatography (DHPLC) has emerged as an alternative to denaturing gradient gel electrophoresis (DGGE) and has already been applied to the study of a few bacterial communities. We propose the application of DHPLC to the study of fungal colonization on paper-based archive materials. This technology allows for the identification of each component of a mixture of fungi based on their genetic variation. In a highly complex mixture of microbial DNA this method can be used simply to study the population dynamics, and it also allows for sample fraction collection, which can, in many cases, be immediately sequenced, circumventing the need for cloning. Some examples of the methodological application are shown. Also applied is fragment length analysis for the study of mixed Candida samples. Both of these methods can later be applied in various fields, such as clinical and sand sample analysis. So far, the environmental analyses have been extremely useful to determine potentially pathogenic/toxinogenic fungi such as Stachybotrys sp., Aspergillus niger, Aspergillus fumigatus, and Fusarium sp. This work will hopefully lead to more accurate evaluation of environmental conditions for both human health and the preservation of documents.

Síntese de acetato de decilo por catálise enzimática em meio supercrítico

Este trabalho teve como objectivo o estudo, em reactor fechado, da produção de ésteres de cadeia longa por catálise enzimática em meio supercrítico com vista ao desenvolvimento de um processo sustentável, tecnologicamente eficiente e limpo e que constitua uma alternativa aos processos químicos tradicionais. Como composto modelo a produzir foi seleccionado o acetato de decilo, um éster com aplicação na indústria de fragrâncias. A reacção estudada foi a transesterificação do acetato de vinilo com o decanol, obtendo-se como principal produto o acetato de decilo. O catalisador escolhido foi a lipase B de Candida antarctica (CALB), imobilizada na resina macroporosa Lewatit B (Novozym 435®). A síntese de acetato de decilo foi estudada numa instalação experimental de alta pressão, equipada com um reactor fechado de volume variável, a operar isotermicamente a 35 ºC e a 100 bar, usando-se como solvente CO2 em condições supercríticas. Fez-se a determinação do conteúdo enzimático por tamanho de partícula de catalisador, tendo-se verificado que as partículas mais pequenas têm uma quantidade específica de enzima mais elevada, havendo uma relação inversamente proporcional entre o conteúdo enzimático e o tamanho de partícula. Verificou-se também que a enzima deve estar localizada numa camada exterior da partícula, seguindo um modelo do tipo “casca de ovo”, sendo a espessura dessa camada de 60 μm (assumindo distribuição uniforme) e independente do tamanho de partícula. Analisaram-se as resistências à transferência de massa, tanto externas como internas. Para as primeiras, fez-se apenas variar a agitação dentro do reactor, mantendo todas as outras condições de operação constantes (temperatura, pressão, quantidade de enzima, tamanho de partícula, concentração de substratos na alimentação). Verificou-se que a partir de 950 r.p.m. as resistências externas à transferência de massa são eliminadas. Relativamente às resistências internas, realizaram-se várias reacções com diferentes tamanhos de partícula, mas com a mesma quantidade de enzima, a mesma concentração dos dois substratos na alimentação, a mesma agitação, temperatura e pressão. Os resultados obtidos mostram que não há influência significativa do tamanho das partículas de catalisador sobre a velocidade inicial de reacção, pelo que as resistências internas à transferência de massa se podem considerar desprezáveis. Estudou-se também o efeito da variação da concentração dos substratos na alimentação sobre as velocidades iniciais de reacção. Observou-se que a partir de uma determinada concentração de decanol em excesso relativamente ao acetato de vinilo, a reacção é inibida pelo álcool. Pelo contrário, a reacção é favorecida quando a alimentação tem excesso de acetato de vinilo, havendo um aumento significativo da sua velocidade inicial. Estes resultados são consistentes com um mecanismo do tipo Ping-pong bi-bi com inibição competitiva por parte do álcool, comum na descrição de reacções enzimáticas de esterificação/transesterificação. Por último, fez-se uma comparação dos resultados obtidos em meio supercrítico (CO2) e em meio orgânico (hexano). Observou-se que as reacções em hexano apresentam uma velocidade inicial significativamente superior.

Prevalencia de deficits nutricionais em criancas menores de cinco anos em Angola

OBJETIVO Estimar a prevalência de déficits nutricionais entre crianças angolanas. MÉTODOS Estudo transversal de base populacional. Para classificação do estado nutricional, foram empregados os critérios da Organização Mundial da Saúde (2006). RESULTADOS Observou-se elevada prevalência de déficits de estatura-para-idade, peso-para-estatura e peso-para-idade (22%, 13% e 7%, respectivamente) entre as crianças. CONCLUSÕES Déficits nutricionais de crianças representam sério problema de saúde pública em Bom Jesus, Angola.