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The teaching-learning process becomes more attractive when practical classes are used as part of methodological tools. Aiming (i) to stimulate the interest of high school students in the microbiological world and (ii) to provide didactic experience for microbiology graduate students, practical classes were undertaken. These classes were carried out during 2016 and 2017 using the infrastructure at Universidade Federal de Viçosa. Briefly, laboratory classes were prepared and taught by microbiology graduate students and an evaluation questionnaire was answered by the participants after the classes. Approximately 95% of high school students, from both years, evaluated the experience outside the school routine as very good and good; in detail, 90.09% (2016) and 100% (2017) of graduate students evaluated this experience as very good and good. The relationship between high school and graduate students also increased the curiosity of the former regarding the university environment. Accordingly, information retention regarding the ‘microbiology world’ was verified after 1 year and the students were able to remember important terms related to the microbiology class. In addition, this work allowed graduate and high school students to build a closer relationship and created an excellent teaching-learning strategy for both.

The RNA chaperone Hfq regulates diverse processes in numerous bacteria. In this study, we compared phenotypes (growth rate, adherence, response to different stress conditions and virulence in Galleria mellonella) of wild-type (WT) and isogenic hfq mutants of three serovars (1, 8 and 15) of the porcine pathogen Actinobacillus pleuropneumoniae. Similar growth in rich broth was seen for all strains except Ap1∆hfq, which showed slightly reduced growth throughout the 24 h time course, and the complemented Ap8∆hfqC mutant had a prolonged lag phase. Differences were seen between the three serovar WT strains regarding adherence, stress response and virulence in G. mellonella, and deletion of hfq affected some, but not all of these phenotypes, depending on serovar. Complementation by expression of cloned hfq from an endogenous promoter only restored some WT phenotypes, indicating that complex regulatory networks may be involved, and that levels of Hfq may be as important as presence/absence of the protein regarding its contribution to gene regulation. Our results support that Hfq is a pleiotropic global regulator in A. pleuropneumoniae, but serovar-related differences exist. These results highlight the importance of testing multiple strains/serovars within a given species when determining contributions of global regulators, such as Hfq, to expression of complex phenotypes.

Várias estações de piscicultura que trabalham com a produção de alevinos ou peixes ornamentais têm apresentado problemas relacionados à predação de larvas, pós-larvas e alevinos por ninfas de insetos da Ordem Odonata. Dessa forma, objetivou-se fazer um levantamento de espécies de odonatos presentes em tanques de criação de peixes em dois municípios da região centro-oeste de Minas Gerais, assim como avaliar o efeito de Bacillus thuringiensis var. israelensis de Barjac sobre ninfas de Pantala flavescens (Fabricius, 1798) (Odonata: Libellulidae). Durante um período de três meses, foram realizadas coletas quinzenais, sendo os insetos adultos capturados com o auxílio de redes entomológicas e as ninfas, através de peneiras de malha fina, acopladas a cabos de madeira. As ninfas capturadas foram levadas para o laboratório onde foram individualizadas em caixas de isopor com capacidade para 2L, vedadas em sua extremidade superior com filó. Logo após a emergência dos adultos, esses foram mortos, acondicionados em envelopes e enviados para serem identificados. Os experimentos laboratoriais foram conduzidos em sala climatizada à 25 ± 2°C, UR de 70 ± 10% e fotofase de 12 horas. Ninfas de segundo ínstar de P. flavescens foram individualmente acondicionadas em caixas de isopor contendo cada uma 500mL de água livre de cloro e, estando essas no terceiro, quinto e sétimo ínstares, foram tratadas com B. thuringiensis var. israelensis, através do produto microbiano Vectobac®, em formulação granulada. O produto foi aplicado diretamente na água do recipiente de criação, em concentração indicada para o controle de larvas de culicídeos, duas concentrações superiores e duas inferiores a essa, além da testemunha, na qual não se aplicou o produto. As avaliações foram realizadas a 24, 48 e 72 horas após a aplicação do produto, registrando-se o número de insetos mortos em cada tratamento. Em ambos os experimentos, as ninfas foram alimentadas com larvas de mosquito da Família Culicidae e peixes recém-nascidos da espécie Poecilia cf. vivípara (Schneider, 1801). Foram identificadas as seguintes espécies: Ischnura fluvialis Selys, 1876; Aphylla theodorina (Navas, 1933); Brachymesia furcata (Hagen, 1861); Erythrodiplax fusca (Rambur, 1842); Miathyria marcella (Selys, 1857); Micrathyria almeidai Santos, 1945; Micrathyria hesperis Ris, 1911; Orthemis discolor (Burmeister, 1839); Perithemis mooma Kirby, 1889 e P. flavescens. Não houve efeito significativo do produto microbiano sobre a espécie estudadaSeveral psiculture stations that deal with fingerlings or ornamental fishes rearing have presented some problems with larvae preying, post-larvae and fingerlings by Odonata Order insect nymphs. Thus, the aim of this work was to survey the Odonata species present in fish-raising tanks in two towns of the Midwest region of Minas Gerais, and also to evaluate the effect of Bacillus thuringiensis var. Barjac israelensis on Pantala flavescens nymphs (Fabricius, 1798) (Odonata: Libellulidae). Fortnightly collections were performed over a three month period. The adult insects were captured with entomological nets and the nymphs with fine mesh sieves, coupled to wooden handles. The captured nymphs were taken to the laboratory where they were individualized in 2L plastic foam boxes and sealed in its upper extremity with tulle. Soon after the adults emergence, they were killed, packed into envelopes and sent to be identified. The laboratory experiments were conducted in an acclimatized room at 25 ± 2°C, RH of 70 ± 10% and 12-hour photophase. Second instar P. flavescens nymphs were packed individually into plastic foam boxes containing 500mL of chlorine free water each one. When they were in the third, fifth and seventh instars, they were treated with B. thuringiensis var. israelensis through the microbial product Vectobac® in granulate formulation. The product was directly applied to the rearing container water at the concentration denoted for the control of culicidae larvae, two superior concentrations, two inferior and also another one, where the product was not applied. The evaluations were done at 24, 48 and 72 hours after the product application, recording the dead insects number in each treatment. In both experiments, the nymphs were fed with Culicidae larvae and new-born fishes of the species Poecilia cf. vivipara Schneider, 1801. The following species were identified: Ischnura fluvialis Selys, 1876; Aphylla theodorina (Navas, 1933); Brachymesia furcata (Hagen, 1861); Erythrodiplax fusca (Rambur, 1842); Miathyria marcella (Selys, 1857); Micrathyria almeidai Santos, 1945; Micrathyria hesperis Ris, 1911; Orthemis discolor (Burmeister, 1839); Perithemis mooma Kirby, 1889 and P. flavescens. There were no significant microbial product effects on the studied species

A presença de formigas (Hymenoptera: Formicidae) em ambientes hospitalares pode constituir um problema de saúde pública, especialmente por serem vetores mecânicos de organismos patogênicos. O trabalho teve como objetivo realizar o levantamento de formigas e analisar a presença de bactérias a elas associadas em dois hospitais regionais de médio porte da cidade de Divinópolis, MG. As coletas foram realizadas mensalmente, durante um período de seis meses. Foram coletadas formigas Pheidole sp1 e sp2, Linepithema humile, Wasmannia auropunctata, Camponotus sp1 e sp2, Odontomachus sp, Solenopsis sp, Acromyrmex sp e Tapinoma melenocephalum. Observou-se que estas transportavam mecanicamente Pseudomonas aeruginosa, Enterococcus, Streptococcus, Staphylococcus patogênico e não patogênico e Escherichia coli. Tais resultados evidenciam a propensão à ocorrência de infecções hospitalares nesses locais pela transmissão mecânica de agentes patogênicos por formigas. The presence of ants (Hymenoptera: Formicidae) in hospital environments may constitute a public health problem, especially since they are mechanical vectors for pathogenic organisms. This study aimed to survey the ant populations and analyze the presence of bacteria associated with them in two medium-sized regional hospitals in the municipality of Divinópolis, Minas Gerais, Brazil. Specimens were collected every monthly over a six-month period. The following ant species were found: Pheidole sp1 and sp2, Linepithema humile, Wasmannia auropunctata, Camponotus sp1 and sp2, Odontomachus sp, Solenopsis sp, Acromyrmex sp and Tapinoma melenocephalum. It was observed that these ants mechanically transported Pseudomonas aeruginosa, Enterococcus, Streptococcus, Escherichia coli and non-pathogenic and pathogenic Staphylococcus. These results show the propensity for occurrences of hospital infections at these sites caused by mechanical transmission of pathogens by ants.

The presence of ants (Hymenoptera: Formicidae) in hospital environments may constitute a public health problem, especially since they are mechanical vectors for pathogenic organisms. This study aimed to survey the ant populations and analyze the presence of bacteria associated with them in two medium-sized regional hospitals in the municipality of Divinópolis, Minas Gerais, Brazil. Specimens were collected every monthly over a six-month period. The following ant species were found: Pheidole sp1 and sp2, Linepithema humile, Wasmannia auropunctata, Camponotus sp1 and sp2, Odontomachus sp, Solenopsis sp, Acromyrmex sp and Tapinoma melenocephalum. It was observed that these ants mechanically transported Pseudomonas aeruginosa, Enterococcus, Streptococcus, Escherichia coli and non-pathogenic and pathogenic Staphylococcus. These results show the propensity for occurrences of hospital infections at these sites caused by mechanical transmission of pathogens by ants.

Several psiculture stations that deal with fingerlings or ornamental fishes rearing have presented some problems with larvae preying, post-larvae and fingerlings by Odonata Order insect nymphs. Thus, the aim of this work was to survey the Odonata species present in fish-raising tanks in two towns of the Midwest region of Minas Gerais , and also to evaluate the effect of Bacillus thuringiensis var. Barjac israelensis on Pantala flavescens nymphs (Fabricius, 1798) (Odonata: Libellulidae). Fortnightly collections were performed over a three month period. The adult insects were captured with entomological nets and the nymphs with fine mesh sieves, coupled to wooden handles. The captured nymphs were taken to the laboratory where they were individualized in 2L plastic foam boxes and sealed in its upper extremity with tulle. Soon after the adults emergence, they were killed, packed into envelopes and sent to be identified. The laboratory experiments were conducted in an acclimatized room at 25 ± 2°C, RH of 70 ± 10% and 12-hour photophase. Second instar P. flavescens nymphs were packed individually into plastic foam boxes containing 500mL of chlorine free water each one. When they were in the third, fifth and seventh instars, they were treated with B. thuringiensis var. israelensis through the microbial product Vectobac® in granulate formulation. The product was directly applied to the rearing container water at the concentration denoted for the control of culicidae larvae, two superior concentrations, two inferior and also another one, where the product was not applied. The evaluations were done at 24, 48 and 72 hours after the product application, recording the dead insects number in each treatment. In both experiments, the nymphs were fed with Culicidae larvae and new-born fishes of the species Poecilia cf. vivipara Schneider, 1801. The following species were identified: Ischnura fluvialis Selys, 1876; Aphylla theodorina (Navas, 1933); Brachymesia furcata (Hagen, 1861); Erythrodiplax fusca (Rambur, 1842); Miathyria marcella (Selys, 1857); Micrathyria almeidai Santos, 1945; Micrathyria hesperis Ris, 1911; Orthemis discolor (Burmeister, 1839); Perithemis mooma Kirby, 1889 and P. flavescens . There were no significant microbial product effects on the studied species