Effectiveness of Two Types of Photostimulable Phosphor Plate Plastic Barrier Envelopes for Prevention of Microbiological Contamination

Abstract Objective: To compare the effectiveness of two types of commercially available photostimulable phosphor plate (PSP) protective barrier envelopes to prevent microbiological contamination. Material and Methods: In this cross-sectional study, 80 barrier envelopes were tested in 40 volunteers. The PSP plates were placed individually in Asia Teb and Soredex protective barrier envelopes and were placed in the mouth for two minutes, similar to periapical films. The protective barrier envelopes were then removed under sterile conditions, and the sensors were placed on different culture media. The number of colonies on each plate was counted. Data were analyzed using SPSS via McNemar and Wilcoxon tests. Results: Bacterial growth was noted in 17.5% of PSPs with Soredex, and 32.5% of PSPs with Asia Teb barrier envelopes. Gram-positive bacilli were the most commonly isolated bacteria. The difference between the Asia Teb and Soredex barrier envelopes for the protection of microbiological contamination was not significant (p>0.05). Conclusion: The use of different types of protective barrier envelopes was not sufficient for prevention of microbiological contamination of PSP plates, and some adjunct modalities were required to decrease microbiological contamination of PSP plates.

La pubertad en niños chilenos muestra un adelantamiento en el inicio del crecimiento testicular / Age of onset of puberty in Chilean boys according to testicular volume and Tanner stage

Background: A secular trend towards a younger age of puberty onset has been reported in Chilean girls. Aim: To evaluate the age of onset of puberty and prevalence of early puberty in Chilean boys. Material and Methods: A pediatric endocrinologist examined 319 children attending schools in central Santiago. Pubertal development was assessed by testicular volume (TV) and genital inspection (GI) using Tanner graduation. Precocious and early puberty development was diagnosed if TV ≥ 4 ml or GI > stage 2 occurred in boys younger than 9 years and at 9-10 years of age, respectively. Results: Pubertal onset occurred at 10.2 ± 1.5 years according to TV and at 11.1 ± 1.6 years according to GI (p < 0.01). Before the age of nine, 15.2% of children had a VT ≥ 4 ml, 3% had genital changes in GI and only 3% had both changes simultaneously. Early puberty was observed in 23.8% of children according to TV and 9.5% according to GI. However, no child of less than 11 years old had a TV ≥ 4 ml, genital changes and pubic hair simultaneously. Late pubertal stages occurred at the same age according to both criteria used. Body mass index z score was not associated with the age of pubertal onset. Conclusions: Testicular enlargement occurs one year earlier than changes in genitalia according to inspection. Testicular growth, but not late stages of puberty, are occurring one year earlier than previously reported in Chile 10 years ago.

Efeitos do aditivo do leite materno com ferro sobre as propriedades bacteriostáticas do leite materno / Effects of human milk fortifier with iron on the bacteriostatic properties of breast milk

OBJETIVO: Comparar o crescimento bacteriano em colostro puro e colostro com aditivo do leite materno contendo ferro. MÉTODOS: Foram comparadas 78 amostras de colostro puro ou colostro com adição de aditivo do leite materno contendo ferro para avaliar o crescimento de Escherichia coli, Staphylococcus aureus e Pseudomonas aeruginosa. Para a análise qualitativa, discos de papel-filtro foram imersos em amostras de cada grupo e incubados por 48 horas com 10¹ Unidades Formadoras de Colônias/mL de cada cepa. Para a avaliação quantitativa, 1 mL de cada cepa contendo 10(7) Unidades Formadoras de Colônias/mL foi homogeneizado com 1 mL, tanto de colostro puro quanto de colostro com aditivo do leite materno, espalhado em placa de Petri e incubado a 37ºC. O número de Unidades Formadoras de Colônias foi contado 24 horas depois. RESULTADOS: A análise qualitativa não mostrou nenhuma diferença no crescimento bacteriano. Na avaliação quantitativa, o crescimento de Escherichia coli (EC) no grupo C foi de 29,4±9,7 x 10(6) CFU/mL, enquanto no grupo FM85 foi de 31,2±10,8 x 10(6) CFU/mL. A diferença entre o crescimento médio foi de 1,9±4,9 x 10(6) CFU/mL (p = 0,001). Não houve diferenças no crescimento de Staphylococcus aureus e Pseudomonas aeruginosa. CONCLUSÃO: A adição de ferro a essa concentração reduz a ação bacteriostática do leite materno contra Escherichia coli.

OBJECTIVE: To compare bacterial growth in pure colostrum versus colostrum with human milk fortifier (HMF) containing iron. METHODS: The growth of Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa in 78 samples of pure colostrum or colostrum with added iron-containing HMF was compared. For qualitative analysis, filter paper discs were immersed in samples from each group and incubated for 48 hours with 10¹ colony forming units (CFUs)/mL of each strain. For quantitative assessment, 1 mL of each strain containing 10(7) CFUs/mL was homogenized with 1 mL of either colostrum or colostrum with human milk fortifier, seeded into a Petri dish, and incubated at 37ºC. Twenty-four hours later, the number of CFUs was counted. RESULTS: The qualitative analysis showed no difference in bacterial growth. In the quantitative evaluation, E. coli growth in the control group was 29.4±9.7 x 10(6) CFU/ mL, while in the HMF group it was 31.2±10.8 x 10(6) CFU/mL. The difference between the average growth was 1.9±4.9 x 10(6) CFU/mL (p = 0.001). There were no differences in S. aureus and P. aeruginosa growth. CONCLUSION: Addition of iron at this concentration reduces breast milk bacteriostatic action against E. coli.

Ação de bacteriocinas de bactérias láticas no controle de Listeria monocytogenes e no aumento da vida de prateleira de mortadela fatiada / Use of bacteriocins from lactic acid bacteria in the control of Listeria monocytogenes and in the shelf life extension of sliced mortadella

As bacteriocinas são peptídeos antimicrobianos produzidos por algumas bactérias, que atuam como bio-conservantes e têm grande potencial de aplicação em produtos cárneos. Estudos mostram que as bacteriocinas de bactérias lácticas (BAL) a serem utilizadas em um determinado alimento são mais eficientes quando produzidas por bactérias lácticas isoladas do mesmo tipo de alimento. Este estudo objetivou obter novas BAL produtoras de bacteriocinas a partir de mortadela fatiada, caracterizar as bacteriocinas produzidas, obter a bacteriocina semi-purificada e verificar seu potencial de aplicação in vitro e in situ no controle de Listeria monocytogenes e na vida de prateleira (VDP) de mortadela fatiada. Foram obtidos 19 isolados de BAL comprovadamente produtoras de bacteriocinas, que foram avaliadas quanto ao espectro de ação frente a uma grande variedade de bactérias Gram positivas e Gram negativas, e estabilidade em diferentes pH. As que apresentaram melhor estabilidade e inibiram maior número de bactérias foram avaliadas quanto a estabilidade térmica e resistência a diferentes agentes químicos e concentrações de NaCl. As que apresentaram maior resistência foram submetidas a testes de otimização da produção da bacteriocina em diferentes combinações de tempo/temperatura. Com base nestes resultados, selecionou-se um isolado que identificado como Lactobacillus curvatus pelo sequenciamento do gene 16S e confirmado por reações de PCR com primers específicos. A bacteriocina produzida por este isolado foi submetida a uma purificação por extração ácida e aplicada em fatias de mortadela experimentalmente contaminadas com um pool de cepas de Listeria monocytogenes, observando-se as contagens deste patógeno durante o armazenamento em refrigeração (7°C) por 40 dias em embalagem à vácuo. Paralelamente, foi realizada contagem de bactérias láticas para avaliar o efeito da bacteriocina nesta população, responsável pela VDP deste produto. A bacteriocina parcialmente purificada foi ...

Bacteriocins are peptides with antimicrobial properties produced by some bacteria, that act as bio-preservatives with great potential of application in meat products. Several studies show that bacteriocins from lactic acid bacteria (LAB) to be used in a specific food product have a better performance when produced by LAB isolated from the same kind of product. This study aimed to obtain new bacteriocinogenic LAB from sliced Bologna, to characterize the bacteriocins produced, to obtain a semi-purified bacteriocin, and to verify its potential of application in vitro and in situ in the control of Listeria monocytogenes and in the shelf-life of sliced bologna. 19 bacteriocin producer LAB, were evaluated as to spectrum of action against a great variety of Gram positives and Gram negatives bacteria and pH stability. The ones with better stability and that inhibited a larger number of bacteria were evaluated according to its thermal stability and resistance against different chemical agents and NaCl concentrations. The ones that showed better resistance were submitted to tests to optimize the bacteriocin production in different combinations of time and temperature. Based on these results, one was selected, identified as Lactobacillus curvatus by gene 16S sequencing and confirmed by PCR reactions with specific primers. The bacteriocin produced by this strain was submitted to partial purification by acid extraction and was applied in mortadella slices experimentally contaminated with a pool of L. monocytogenes strains, observing the counts of this pathogen along refrigerated (7ºC) storage fo r 40 days in vacuum package. Parallel, it was done LAB counts to evaluate the effect of the bacteriocin on this population, responsible for limiting the shelf life of this product. The semi-purified bacteriocin was able to reduce 1 log cicle of the initial population of L. monocytogenes in the sliced mortadella, which was maintained during the 40 days of analysis. Along the whole...

Ficus cunia agglutinin for recognition of bacteria.

Interaction of bacteria with lectin using anti-lectin antibody by ELISA is an established method. In the present study, we have devised a simple ELISA using a biotinylated lectin and antibiotin-HRP. Ficus cunia agglutinin (FCA), which has shown the specificity towards alpha/beta anomers of GlcNAc and other-NAc containing sugars like LacNAc and GlcNAcbeta(1-4/6)GlcNAc, was used as a model lectin for the study of interaction with immobilized microorganisms on ELISA plate. The bacterial cells of E. coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Bacillus subtilis and Staphylococcus aureus showed binding with FCA and the degree of binding was dependent on the bacterial surface antigen. This method is considered a simple technique to study the lectin-bacteria interaction.

Alteraciones inmunológicas en endocarditis infecciosa / Immunological alterations in infectious endocarditis

La EI es una patología compleja, en cuya patogenia convergen factores de diversa naturaleza: infecciosos, hemodinámicos, inmunológicos, entre otros. La infección crónica constituye un estímulo antigénico persistente que induce una respuesta inmune que resulta ineficiente frente al agresor, llevando a la aparición de múltiples alteraciones inmunológicas, entre ellas alteraciones autoinmunes. Estas pueden tener o no una traducción clínica, incluso pueden simular una enfermedad autoinmune o de base inmune, por lo que el diagnóstico diferencial preciso y oportuno es fundamental. Si bien condiciones coexistentes, asociadas a inmunodeficiencia, pueden favorecer la aparición de la EI, o incidir en una mayor mortalidad, no se ha encontrado un defecto inmunológico específico en esta patología.

Identificaçåo de bactérias gram positivas resistentes à vancomicina / Identification of vancomycin resistant gram positive bacteria

Infecçöes por bactérias Gram positivas resistentes à vancomicina têm surgido com aior frequência nos últimos anos, causando problemas clínicos e terapêuticos. Os laboratórios de microbiologia devem adequar-se técnicamente para detecçåo e identificaçåo destes microorganismos. Apresentamos uma revisåo bibliográfica sobre a importância clínica destes agentes bem como um fluxograma simplificado para sua correta identificaçåo

Atividade antimicrobiana em xantonas / Antimycrobial activity in xanthones

Cerca de treze xantonas isoladas de duas espécies do gênero Haploclathra foram submetidos à açäo de microorganismos-teste. Foram eleitos um fungo (Thielaviopsis paradoxa), uma bactéria Gram-positiva (Corynebacterium michiganense pv michiganense) e uma bactéria Gram-negativa (Pseudomonas syringae pv pisi). Nenhuma das xantonas testadas apresentou resultados positivos na inibiçäo do crescimento dos microorganismos em questäo.

Estudo da atividade antimicrobiana de extrato de folha de Aristolochia gigantea Mart e Zucc / Study of the antimycrobial activity of extracts from the leaves of Aristolochia gigantea Mart and Zucc

Foram investigadas as atividades antibacteriana e antifúngica dos extratos éter de petróleo e alcaloídico de folhas de Aristolochia gigantea Mart e Zucc, pelo método de difusäo em agar. O extrato éter de petróleo mostrou atividade contra uma bactéria Gram-positiva. O extrato alcaloídico apresentou atividade contra duas bactérias Gram-positivas. Uma Gram-negativa, näo apresentando qualquer atividade antifúngica.