Colony Age of Trichoderma azevedoi Alters the Profile of Volatile Organic Compounds and Ability to Suppress Sclerotinia sclerotiorum in Bean Plants.

Common bean (Phaseolus vulgaris L.) is one of the most important crops in human food production. The occurrence of diseases, such as white mold, caused by Sclerotinia sclerotiorum can limit the production of this legume. The use of Trichoderma has become an important strategy in the suppression of this disease. The aim of the present study was to evaluate the effect of volatile organic compounds (VOCs) emitted by Trichoderma azevedoi CEN1241 in five different growth periods on the severity of white mold in common bean. The in vitro assays were carried out in double-plate and split-plate, and the in vivo assays, through the exposure of the mycelia of S. sclerotiorum to the VOCs of T. azevedoi CEN1241 and subsequent inoculation in bean plants. Chemical analysis by gas chromatography coupled to mass spectrometry detected 37 VOCs produced by T. azevedoi CEN1241, covering six major chemical classes. The profile of VOCs produced by T. azevedoi CEN1241 varied according to colony age and was shown to be related to the ability of the biocontrol agent to suppress S. sclerotiorum. T. azevedoi CEN1241 VOCs reduced the size of S. sclerotiorum lesions on bean fragments in vitro and reduced disease severity in a greenhouse. This study demonstrated in a more applied way that the mechanism of antibiosis through the production of volatile compounds exerted by Trichoderma can complement other mechanisms, such as parasitism and competition, thus contributing to a better efficiency in the control of white mold in bean plants.

BioSin UFMG Club: Engaging a multilevel and multidisciplinary community in synthetic biology.

Learning synthetic biology is often seen as a far distant possibility, restricted to those who have the privilege of an academic career. We propose a student-centered discussion group around synthetic biology, aimed at people from high school onwards with different backgrounds to interact and learn about synthetic biology. We developed a 14-week long program with three modules: "Leveling," "Introducing," and "Discussion." By completing the first two modules, the members should be more comfortable with biological names, structures, concepts, and techniques. The modules developed are available in Portuguese, Spanish, and English via the Open Lab Idea Real website (https://ideareal.org/clube-de-biologia-sintetica/) and can be used to implement the Club either in place or virtually around the world. We put it to practice at Universidade Federal de Minas Gerais (UFMG) creating the Club named BioSin. There are programs such as the International Genetically Engineered Machine (iGEM) competition focused on disseminating synthetic biology. Although iGEM is one fantastic way of learning about synthetic biology, there is a high cost. Because of that, a study and discussion Club is a tool to spread knowledge and engage with the study area.

Mycelial Inhibition of Sclerotinia sclerotiorum by Trichoderma spp. Volatile Organic Compounds in Distinct Stages of Development.

<b>Background and Objective:</b> Fungi of the genus <i>Trichoderma </i>have high versatility in the control of different plant diseases. Among the main mechanisms of action of these fungi against phytopathogenic fungi, the production of Volatile Organic Compounds (VOCs) is mentioned. These compounds are said to inhibit the mycelial growth of various fungal pathogens. The objective of this work was to evaluate the <i>in vitro</i> inhibition of the mycelial growth of <i>Sclerotinia sclerotiorum </i>by VOCs from six <i>Trichoderma </i>strains in different stages of development of the biocontrol agent. <b>Materials and Methods:</b> In this work, the <i>in vitro </i>evaluation of the mycelial growth of the phytopathogen <i>S. sclerotiorum </i>by VOCs from six <i>Trichoderma </i>strains was carried out: <i>T. koningiopsis </i>(CEN1386), <i>T. asperelloides </i>(CEN1397), <i>T. longibrachiatum </i>(CEN1399) <i>T. lentiforme </i>(CEN1416), <i>T</i>. <i>perbedyi</i> (CEN1389) and <i>T. azevedoi</i> (CEN1241). Observations were made at different stages of antagonist development: mycelial Growth Phase (GP), Sporulation Phase (SP) and paired with the Pathogen Phase (PP). Besides, the sporulation of the tested strains was quantified. <b>Conclusion:</b> In all experimental conditions, the VOCs produced by the CEN1241 strain showed a greater inhibitory effect, although the inhibition was less evident when the cultures of <i>S. sclerotiorum </i>were exposed in the GP phase of the antagonist. Greater sporulation was observed with <i>T. lentiforme</i> (CEN1416), a fact not related to a better ability to inhibit <i>S. sclerotiorum</i>, by VOCs.

Clinical pathology differences in laboratory utilization in hospice and nonhospice units.

A significant difference can be observed between hospice and nonhospice philosophy. Nonhospice units direct its effort to cure and sustain patient's life using disease-modifying therapeutic procedures, while hospice units focus on patient's quality of life. However, despite the differences between the 2 basic philosophies in question, both approaches share 1 aspect in common: the correct diagnosis of the patient. In any case above, laboratory analysis is a valuable tool. This work aims to compare the laboratory utilization between nonhospice cancer and hospice cancer units. Laboratory requests from patients within a 1-year period were evaluated and the hospice laboratory profile was presented. We demonstrated that nonhospice unit had a major volume of requested laboratory test than hospice unit, but for inpatients this difference was not so dramatic.

Determinaçao de especies de estafilococos coagulase-negativos de significado clinico / Species identification of coagulase-negative staphylococci of clinical significance

Uma coleçao de 141 amostras de estafilococos coagulase-negativos, isoladas de especimes clinicos, assim como de portadores e ambiente hospitalar, foram analisadas quanto as caracteristicas fisiologicas e propriedades biologicas. Oito especies foram identificadas pelos metodos convencionais segundo Kloos & Schleifer, e corresponderam a S. saprophyticus, S. epidermis, S. cohnil, S. simulans, S. hominis, S. warneri, S. haemolyticus e S. xylosus. Quatorze amostras nao foram identificadas. Atraves da aplicaçao da tecnica de taxonomia numerica se observou uma tendencia para a separaçao em dois grandes grupos, compreendendo S. saprophyticus e S. epidermidis. A partir dai as amostras restantes se identificaram com as outras especies de referencia de diferentes graus de similaridade. O emprego do micrometodo API no estudo de 39 das amostras ja identificadas so permitiu a classificaçao de 17 cepas em especies.

Cinética da sensibilidade bacteriana: proposta de uma função de sensibilidade bacteriana aos antimicrobianos

O comportamento de 52 cepas bacterianas: foi analisado frente a concentrações regularmente crescentes de antibiótico (G). Utilizou-se técnica turbidimétrica, através da medida da densidade ótica (DO). Foram estudadas 40 cepas de enterobactérias, 11 cepas de bactérias anaeróbias estritas e 1 cepa de mycobacterium como representante de gênero de crescimento lento. Uma função de sensibilidade (F sa) é proposta e designada “curva de sensibilidade cinética (CSC). A partir da medida experimental da DO j para cada concentração de antibiótico Cj, j = 0,1...10,5 parâmetros foram estimados para caracterização do comportamento de cada cepa individualmente ao antibiótico (cefalotina para enterobactérias, cloranfenicol para anaeróbios estritos e estreptomicina para micobactéria). A comparação dos parâmetros da CSC com os valores da concentração inibitória mínima (CIM) sugere tratar-se de fenomenologia diferenciada apesar de apresentarem aspectos correlacionáveis. A comparação da CSC utilizando-se os parâmetros estimados ou mesmo diretamente a medida da DO j revelou boa correlação com os resultados obtidos pela técnica de difusão em ágar com disco. Comportamento não regular quanto a dinâmica da CSC foi observado em algumas cepas estudadas. Este fenômeno parece estar relacionado a uma heterogeneidade intrínseca” e uma indeterminação na medida da CIM. As possíveis implicações desta “heterogeneidade” foram analisadas através de simulação. Os resultados obtidos forneceram hipóteses quanto aos mecanismos implicados na dissociação dos testes in vitro e as observações clínicas

The behavior of 52 bacterial strains : was analysed against regular increasing antibiotic concentrations (Cj) by measuring the optical density (Odj). We studied 40 strains of Enterobacteriaceae Mycobacterium tuberculosis. A sensibility function (Fsa) is proposed and designated as “Kinetic Sensibility Curve”. Sttarting from the experimental measure of the OD j to each antibiotic concentration Cj (j = 0,1, … 10), 5 parameters were estimated to characterize the individual response of each strain to the antibiotic. The comparison of the Kinetic Sensibility Curve using the estimated parameters with the values of the minimum inibitory concentration (MIC) obtained by the dilution technique suggests different instrinsic phenomenon, although one can show some similar aspects. The comparison of the estimated parameters or even the experimental DO (j = 10) with the results obtained by the disk diffusion technique revealed good correlation. Some of the strains studied have showed a non-regular dynamics of the Kinetic Sensibility Curve. This phenomenous seems to be related to an intrinsic population heterogeneity of the bacterial population and a MIC indetermination. The possible implications of this heterogeneity was analysed using simulation technique. The obtained results give us some hipotheses about the mechanism implicated in the dissociation between the in vitro tests and the clinical observations