Análise do perfil microbiológico de agentes causadores de mastite bovina e sua relação com a qualidade do leite em uma fazenda do Sul de Minas Gerais/Analysis of the microbiological profile of causative agents of bovine mastitis and their relationship with milk quality in a south farm of Minas Gerais

A mastite é caracterizada pela inflamação de glândulas mamárias causada principalmente por bactérias e tendo como principal isolado o coco Gram positivo Staphylococcus aureus. Neste trabalho, a prevalência de mastite foi avaliada quanto à interferência na qualidade e na composição do leite em uma pequena fazenda no município de Campos Gerais – MG. Amostras de leite de 27 animais em lactação (saudáveis e positivos para mastite em suas formas clínica e subclínica) foram analisadas quanto à composição (teores de gordura, de proteína, de lactose e de sólidos totais), contagem de células somáticas e caracterização microbiológica com posterior avaliação de perfil de sensibilidade a diversos antibióticos. Observamos diferença significativa entre os grupos quanto ao teor de lactose, mas o número de animais analisados não apresentou correlação estatística entre patologia e composição. Nos animais positivos para mastite foram isolados Staphylococcus aureus (37,5%), Escherichia coli (25,0%), Streptococcus sp. (12,5%) e leveduras (25,0%); sendo os microrganismos sensíveis à maioria dos antimicrobianos testados. Também foi avaliada a capacidade de formação de biofilme por isolados de S. aureus em que observamos a formação de biofilme em 66,66% dos isolados. Estes dados chamam a atenção para a necessidade de uma correta identificação do agente causador da mastite para um tratamento direcionado da mesma, visando estratégias de controle mais eficientes e, consequentemente, auxiliando na melhora da qualidade do leite, propiciando assim com que os consumidores possam adquirir produtos lácteos com maior qualidade e segurança

Identificação e análise de resistência à oxacilina de bactérias residentes da microbiota nasal de indivíduos hospitalizados e não hospitalizados no Município de Varginha – MG/ Identification and oxacillin resistance analysis of isolated bacteria from nasal microbiota of hospitalized and non-hospitalized individuals from the City of Varginha-MG

Increasing rates of antibiotic-resistant microbial infections, both in hospitals and in society, have raised considerable concern for the health community, as these infectious diseases continue to be the leading cause of mortality worldwide. The nasal microbiota is an important reservoir of pathogenic bacteria. Resident microorganisms of the nasal microbiota have shown high rates of mutagenicity and antimicrobial resistance. This study aimed to identify which bacteria are present in the nasal cavity of people in the community and their susceptibility profile to the antibiotics discussed above, and finally to make a comparison between the data obtained in the community and the data obtained from individuals hospitalized in previous research. This purpose was achieved from the analysis of samples of nasal material from students of the University Center of Southern Minas - UNIS / MG. The samples were collected by sterile swab and subsequently analyzed in the microbiology laboratory of the same institution. Finally, oxacillin susceptibility testing was performed using the Mueller Hinton Agar Disc Diffusion technique following the standardization of the Clinical & Laboratory Standards Institute (CLSI). A higher number of oxacillin-resistant bacteria was found in hospitalized subjects. However, although in smaller numbers, resistant bacteria were found in the individuals of society, reflecting the need for an incentive to develop new drugs and especially methods that slow down the increase of resistance and contribute to the awareness about the proper use of antibiotics

Schistosoma mansoni SmKI-1 or Its C-Terminal Fragment Induces Partial Protection Against S. mansoni Infection in Mice

Current schistosomiasis control strategies are mainly based on chemotherapy, but the development of a vaccine against this parasitic disease would contribute to a long-lasting decrease in disease spectrum and transmission. When it comes to vaccine candidates, several genes encoding Schistosoma mansoni proteins expressed at the mammalian host–parasite interface have been tested. Among the most promising molecules are the proteins present on the tegument and digestive tract of the parasite. In this study, we evaluate the potential of SmKI-1, the first Kunitz-type protease inhibitor functionally characterized in S. mansoni, as a vaccine candidate. Bioinformatic analysis points to the C-terminal fragment as the main region of the molecule responsible for the development of a potential protective immune response induced by SmKI-1. Therefore, for the vaccine formulations, we produced the recombinant (r) SmKI-1 and two different fragments, its Kunitz (KI) domain and its C-terminal tail. First, we demonstrate that mice immunized with recombinant SmKI-1 (rSmKI-1) or its fragments, formulated with Freund’s adjuvant, induced the production of IgG-specific antibodies. Further, all vaccine formulations tested here also induced a Th1-type of immune response, as suggested by the production of IFN-γ and TNF-α by protein-stimulated cultured splenocytes. However, the protective effect conferred by vaccination was only observed in groups which received rSmKI-1 or C-terminal domain vaccines. Mice administered with rSmKI-1 demonstrated reduction of 47% in worm burden, 36% in egg number in mouse livers, and 33% in area of liver granulomas. Additionally, mice injected with C-terminal domain showed reduction of 28% in worm burden, 38% in egg number in liver, and 25% in area of liver granulomas. In contrast, KI domain immunization was unable to reduce worm burden and ameliorate liver pathology after challenge infection. Taken together, our data demonstrated that SmKI-1 is a potential candidate for use in a vaccine to control schistosomiasis, and its C-terminal tail seems to be the main region of the molecule responsible for protection conferred by this antigen

S. mansoni SmKI-1 Kunitz-domain: Leucine point mutation at P1 site generates enhanced neutrophil elastase inhibitory activity.

The Schistosoma mansoni SmKI-1 protein is composed of two domains: a Kunitz-type serine protease inhibitor motif (KD) and a C-terminus domain with no similarity outside the genera. Our previous work has demonstrated that KD plays an essential role in neutrophil elastase (NE) binding blockage, in neutrophil influx and as a potential anti-inflammatory molecule. In order to enhance NE blocking capacity, we analyzed the KD sequence from a structure-function point of view and designed specific point mutations in order to enhance NE affinity. We substituted the P1 site residue at the reactive site for a leucine (termed RL-KD), given its central role for KD's inhibition to NE. We have also substituted a glutamic acid that strongly interacts with the P1 residue for an alanine, to help KD to be buried on NE S1 site (termed EA-KD). KD and the mutant proteins were evaluated in silico by molecular docking to human NE, expressed in Escherichia coli and tested towards its NE inhibitory activity. Both mutated proteins presented enhanced NE inhibitory activity in vitro and RL-KD presented the best performance. We further tested RL-KD in vivo in an experimental model of monosodium urate (MSU)-induced acute arthritis. RL-KD showed reduced numbers of total cells and neutrophils in the mouse knee cavity when compared to KD. Nevertheless, both RL-KD and KD reduced mice hypernociception in a similar fashion. In summary, our results demonstrated that both mutated proteins showed enhanced NE inhibitory activity in vitro. However, RL-KD had a prominent effect in diminishing inflammatory parameters in vivo

data_sheet_1_Schistosoma mansoni SmKI-1 or Its C-Terminal Fragment Induces Partial Protection Against S. mansoni Infection in Mice.PDF

<p>Current schistosomiasis control strategies are mainly based on chemotherapy, but the development of a vaccine against this parasitic disease would contribute to a long-lasting decrease in disease spectrum and transmission. When it comes to vaccine candidates, several genes encoding Schistosoma mansoni proteins expressed at the mammalian host–parasite interface have been tested. Among the most promising molecules are the proteins present on the tegument and digestive tract of the parasite. In this study, we evaluate the potential of SmKI-1, the first Kunitz-type protease inhibitor functionally characterized in S. mansoni, as a vaccine candidate. Bioinformatic analysis points to the C-terminal fragment as the main region of the molecule responsible for the development of a potential protective immune response induced by SmKI-1. Therefore, for the vaccine formulations, we produced the recombinant (r) SmKI-1 and two different fragments, its Kunitz (KI) domain and its C-terminal tail. First, we demonstrate that mice immunized with recombinant SmKI-1 (rSmKI-1) or its fragments, formulated with Freund’s adjuvant, induced the production of IgG-specific antibodies. Further, all vaccine formulations tested here also induced a Th1-type of immune response, as suggested by the production of IFN-γ and TNF-α by protein-stimulated cultured splenocytes. However, the protective effect conferred by vaccination was only observed in groups which received rSmKI-1 or C-terminal domain vaccines. Mice administered with rSmKI-1 demonstrated reduction of 47% in worm burden, 36% in egg number in mouse livers, and 33% in area of liver granulomas. Additionally, mice injected with C-terminal domain showed reduction of 28% in worm burden, 38% in egg number in liver, and 25% in area of liver granulomas. In contrast, KI domain immunization was unable to reduce worm burden and ameliorate liver pathology after challenge infection. Taken together, our data demonstrated that SmKI-1 is a potential candidate for use in a vaccine to control schistosomiasis, and its C-terminal tail seems to be the main region of the molecule responsible for protection conferred by this antigen.</p

data_sheet_2_Schistosoma mansoni SmKI-1 or Its C-Terminal Fragment Induces Partial Protection Against S. mansoni Infection in Mice.PDF

<p>Current schistosomiasis control strategies are mainly based on chemotherapy, but the development of a vaccine against this parasitic disease would contribute to a long-lasting decrease in disease spectrum and transmission. When it comes to vaccine candidates, several genes encoding Schistosoma mansoni proteins expressed at the mammalian host–parasite interface have been tested. Among the most promising molecules are the proteins present on the tegument and digestive tract of the parasite. In this study, we evaluate the potential of SmKI-1, the first Kunitz-type protease inhibitor functionally characterized in S. mansoni, as a vaccine candidate. Bioinformatic analysis points to the C-terminal fragment as the main region of the molecule responsible for the development of a potential protective immune response induced by SmKI-1. Therefore, for the vaccine formulations, we produced the recombinant (r) SmKI-1 and two different fragments, its Kunitz (KI) domain and its C-terminal tail. First, we demonstrate that mice immunized with recombinant SmKI-1 (rSmKI-1) or its fragments, formulated with Freund’s adjuvant, induced the production of IgG-specific antibodies. Further, all vaccine formulations tested here also induced a Th1-type of immune response, as suggested by the production of IFN-γ and TNF-α by protein-stimulated cultured splenocytes. However, the protective effect conferred by vaccination was only observed in groups which received rSmKI-1 or C-terminal domain vaccines. Mice administered with rSmKI-1 demonstrated reduction of 47% in worm burden, 36% in egg number in mouse livers, and 33% in area of liver granulomas. Additionally, mice injected with C-terminal domain showed reduction of 28% in worm burden, 38% in egg number in liver, and 25% in area of liver granulomas. In contrast, KI domain immunization was unable to reduce worm burden and ameliorate liver pathology after challenge infection. Taken together, our data demonstrated that SmKI-1 is a potential candidate for use in a vaccine to control schistosomiasis, and its C-terminal tail seems to be the main region of the molecule responsible for protection conferred by this antigen.</p