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Visto como um dos principais problemas econômicos e sanitários nas propriedades brasileiras, a mastite bovina mostra-se como uma doença de grande prevalência dentre os animais de produção. Um dos principais gargalos referente a tal enfermidade é a resistência antimicrobiana, em especial, quando a etiologia está associada a bactéria Staphylococcus aureus. Nessa perspectiva, o presente trabalho tem por objetivo discorrer sobre o perfil de resistência de S. aureus e alguns fatores envolvidos. Para tal, os dados foram apresentados na forma de uma revisão narrativa da literatura, tendo como embasamento estudos indexados as plataformas: Portal de Periódicos CAPES-MEC e SciELO. Foi verificado na pesquisa bibliográfica um acentuado perfil de resistência antimicrobiana do S. aureus, sendo os antibióticos menos eficazes a Penicilina e Ampicilina e o de melhor eficácia no tratamento a Cefalotina. Outros dados compilados foram: o de que animais mais velhos possuem maior chance de apresentarem resistência aos tratamentos antimicrobianos e de que em algumas situações o custo-benefício do tratamento de mastite subclínica por S. aureus não traz retornos econômicos, mas somente na melhoria da qualidade do leite. Nesse contexto, ressalta-se a importância de novas pesquisas para traçar a evolução da resistência antimicrobiana do S. aureus, bem como fomentar atividades extencionistas para educação no campo sobre os corretos procedimentos terapêuticos da mastite bovina.

INTRODUÇÃO: Os ecossistemas de água doce sustentam uma enorme biodiversidade e fornecem bens e serviços ambientais de importância para as populações humanas. O uso do sequenciamento massivo de fragmentos amplificados de DNA derivados de amostras de ambientes fluviais poderiam ser usados para determinar a biodiversidade e composição das comunidades microbianas destes ambientes. Em ambientes aquáticos, os sedimentos se tornam um local ideal para o crescimento microbiano, uma vez que nesse ambiente os microrganismos podem se fixar e realizar seu metabolismo. As características dos sedimentos refletem o status trófico e a função ecológica dos rios, porque os sedimentos contêm milhares de microrganismos, que interagem com a matéria orgânica e afetam diretamente os ecossistemas. OBJETIVOS: Caracterizar as comunidades microbianas do sedimento do leito do Rio São Francisco na região da Serra da Canastra em Minas Gerais. MATERIAIS E METODOS: Foram coletadas amostras do sedimento do rio São Francisco em 3 áreas distintas: na nascente do rio (20°14'35.27"S 46°26'47.44"O), Casca D’Anta (20°19'52.95"S 46°21'56.53"O) e área rural (20°10'19.33"S 45°42'57.98"O). As amostras foram levadas ao laboratório para extração de DNA. A caracterização das comunidades procarióticas típicas de cada amostra foi realizada através do sequenciamento da região V4 do gene rDNA 16S. Os dados gerados foram submetidos à plataforma de análise de dados de microbiomas QIIME2TM e seguindo os parâmetros sugeridos pelo The Earth Microbiome Project. Ao final foi gerada uma tabela contento a lista de OTUs presentes em cada amostra e seu grupo procariótico classificado de Domínio à até o nível taxonômico mais refinado possível. RESULTADOS: Foram encontrados diversos filos (Cyanobacteria, Actinobacteria, Cloriflexi, Actinobacteria, Verrucomicrobia, etc), famílias (Micrococcaceae, Anaerolinaeceae, Bacillales, Pseudomonadaceae, Acidobacteriales, Burkholderiaceae e Xanthobacteriace) e gêneros (Paraburkholderia, Streptococcus, Acidothermus, Reseiarcus e Pseudomonas) sendo que alguns são dominantes em certos ambientes. CONCLUSÃO: Os resultados apresentados nesse estudo são importantes para a compreensão da ecologia e funcionalidade das comunidades microbianas nos ambientes amostrados.

Ornithonyssus sylviarum is a hematophagous mite present in wild, domestic, and synanthropic birds. However, this mite can affect several vertebrate hosts, including humans, leading to dermatitis, pruritus, allergic reactions, and papular skin lesions. This study evaluated the epidemiological characteristics of O. sylviarum attacks on poultry workers, including data on laying hens, infrastructure and management of hen houses, and reports of attacks by hematophagous mites. In addition, a case of mite attack on a farm worker on a laying farm in the Midwest region in Minas Gerais is presented. It was found that 60.7% farm workers reported attacks by hematophagous mites. Correspondence analysis showed an association between reports of mite attacks in humans with (1) presence of O. sylviarum in the hen house, (2) manual removal of manure by employees, and (3) history of acaricide use. The specimens collected from the location were confirmatively identified as O. sylviarum. O. sylviarum attacks ave not been reported when manure was removed in a shorter time interval and did not use acaricide in the sheds when the removal was done by manure conveyor belt. Parasitism by O. sylviarum should be considered a relevant occupational hazard affecting employees working in direct contact with commercial egg-laying hens in Minas Gerais. We emphasized the need to monitor hen infestations by this mite to improve the development of mite control strategies. RESUMO: Ornithonyssus sylviarum é um ácaro hematófago de aves silvestres, domésticas e sinantrópicas. No entanto, este ácaro pode afetar vários hospedeiros vertebrados, incluindo humanos, levando a dermatites, prurido, reações alérgicas e lesões cutâneas papulosas. O presente estudo avaliou os aspectos epidemiológicos do ataque de O. sylviarum em trabalhadores de granjas avícolas e descreveu um relato de caso em uma granja de postura. Este estudo utilizou um banco de dados secundário com informações sobre as poedeiras, infraestrutura e manejo dos galinheiros e relatos de ataques por ácaros hematófagos. Foi apresentado um caso de ataque de ácaro a um trabalhador rural no Centro-Oeste em Minas Gerais. Houve uma frequência de 60,7% de trabalhadores que relataram ter sido atacados por ácaros hematófagos em fazendas. A análise de correspondência mostrou uma associação entre relatos de ataques de ácaros em humanos com (1) presença de O. sylviarum na fazenda, (2) remoção manual de esterco por funcionários da fazenda e (3) histórico de uso de acaricidas. Os espécimes coletados do local foram identificados como O. sylviarum. Não há ataques de O. sylviarum, quando a remoçãodo esterco é feita em menor intervalo de tempo, e não se utiliza acaricida nos galpões quando a remoção é feita por esteira transportadora de esterco. Conclui-se que o parasitismo por O. Sylviarum deve ser considerado como um risco ocupacional relevante, que afeta trabalhadores que trabalham diretamente com poedeiras comerciais em Minas Gerais. Ressaltamos a necessidade de monitorar as infestações de aves por esse ácaro, a fim de melhorar o desenvolvimento de estratégias de controle.

Phthiraptera are lice highly adapted to living as permanent and obligatory ectoparasites of birds and mammals. High infestations by biting lice contribute to the low productivity, loss quality of the eggs, besides weight decrease of chickens. Therefore, this study aimed to evaluate and to characterize the risks involved with the presence of biting lice in laying chicken from Minas Gerais, Brazil, throught a Multiple Correspondence Analysis (MCA). A secondary database with information regarding 402 chicken houses from 42 properties of laying hens from the same region was used and adapted for this study. The variables that composed the correspondence model were selected through Chi-square tests (p ≤ 0.05). A risk index was designed to relate the presence of biting lice out of variables such as risk factors related to the presence of these ectoparasites. The MCA graphic designed to conduct the epidemiological characterization of the presence of biting lice presented a Chi-square accumulated value of 53.59%. There was an association between the risk index and the synanthropic birds, subsistence hens, presence of lice and other ectoparasites in shelters and ectoparasites control. These results provide knowledge about the Phthiraptera epidemiology. Besides that, this information may contribute to the decision-making process in order to reduce the risk of possible infestations in poultry farms and the negative effects of the infestations.

In this study, we designed and developed novel biocompatible ZnS quantum dot (QD) nano-immunoconjugates to detect cancer cells strictly via an environmentally-friendly chemistry process. ZnS QDs were capped by chitosan-based ligands that were chemically conjugated at room temperature with an antibody-specific cancer biomarker for non-Hodgkin lymphoma using a one-pot aqueous colloidal route. The nano-immunoconjugates were extensively characterised by several spectroscopic and morphological approaches and biological assays. The results demonstrated that ultra-small colloidal ZnS nanocrystals with an average diameter of 3.7 nm were produced and stabilised by the chitosan-antibody conjugates. In addition, they exhibited intense fluorescence activity and were effective for specific targeting, labelling, and bioimaging of cancerous lymphocyte B-cells. Moreover, the results of in vitro cell viability assays using fibroblast cell line indicated that the ZnS-nanoconjugates were cytocompatible. These may be used in numerous applications in oncology diagnosis and nanomedicine.

The evaluation of the health status of wild populations has received much attention in conservation projects, as it is considered an important but neglected component of species’ ecological fitness. Considering the increasing interest in the conservation and health of Neotropical wildlife species, the aim of this study was to improve the knowledge on blood parameters of maned wolf (Chrysocyon brachyurus) populations from two different protected areas. We performed comparisons of hematological and serum biochemistry data (urea and creatinine dosage) from a total of 17 healthy adult maned wolves cage-trapped and chemically restrained in Serra do Cipo National Park (four females and three males) and Galheiro Private Natural Reserve (four females and six males), both located in Southeast Brazil. Lymphocyte counts were significantly higher in males from the smallest and non-buffered area, the private reserve, which most likely reflects differences in pathogen exposure. Serum creatinine and urea concentrations were higher in females and in animals of both genders from the largest and buffered area, the national park, the latter of which we hypothesized to be an effect of greater protein intake due to higher prey availability. The results highlight that there are slight differences in physiological parameters between populations of wild mammal species, which must be taken into account in health evaluations or assessments of the effects of anthropogenic disturbance on wildlife health.

Wild canids are under many pressures, including habitat loss, fragmentation and disease. The current lack of information on the status of wildlife health may hamper conservation efforts in Brazil. In this paper, we examined the prevalence of canine pathogens in 21 free-ranging wild canids, comprising 12 Cerdocyon thous (crab-eating fox), 7 Chrysocyon brachyurus (maned wolf), 2 Lycalopex vetulus (hoary fox), and 70 non-vaccinated domestic dogs from the Serra do Cipó National Park area, Southeast Brazil. For wild canids, seroprevalence of antibodies to canine parvovirus, canine adenovirus, canine coronavirus and Toxoplasma gondii was 100 (21/21), 33 (7/21), 5 (1/19) and 68 (13/19) percent, respectively. Antibodies against canine distemper virus, Neospora caninum or Babesia spp. were not found. We tested domestic dogs for antibodies to canine parvovirus, canine distemper virus and Babesia spp., and seroprevalences were 59 (41/70), 66 (46/70), and 42 (40/70) percent, respectively, with significantly higher prevalence in domestic dogs for CDV (P

The aims of this study were to devise a process for raising antibodies against Brazilian Bothrops venom in chicken egg yolks, to determine the best delipidation method for the preparation of the aqueous extract and to define the best purification conditions for IgY bothropic antivenom produced in eggs from hens immunized with Brazilian standard bothropic antigen. A group of nine Single Comb White Leghorn laying hens were immunized with venom from five different species of pit vipers of the genus Bothrops. The immunization process was carried out in three cycles, each performed six weeks apart. For extraction, the egg yolk was diluted 1:10 in distilled water, adjusted to a pH of 5.0, subjected to a freeze-thaw cycle, centrifuged and filtered before being precipitated with 20%(w/v) ammonium sulfate salt. This methodology retrieved 2.57 mg of IgY/ml of yolk from eggs. This preparation yielded antibodies capable of neutralizing lethal toxic activity of the pool of Bothrops sp venoms from five species, with an effective dose (ED50) of 365 microL/2 LD50 and, 1.0 mL of IgY antivenom neutralized 0.154 mg of venom.

Background Despite the crucial role of domestic dogs as reservoirs for zoonosis and some of the most threatening diseases for wild carnivores such as distemper and parvovirosis, little is known about the epidemiological features and the risk factors involved in pathogen exposure of dogs that live in human/wildlife interfaces and actually contacts wildlife. Through a cross-sectional serological approach and questionnaire survey, we assessed the prevalence along with individual and environment-associated risk factors for four important viral diseases of rural dogs living in households around six Atlantic Forest fragments in southeast Brazil. Results Widespread exposure to canine parvovirus (97 %), canine distemper virus (15 %) and canine adenovirus (27 %) was detected, but none for canine coronavirus. Dogs from small private reserves were more exposed to parvovirus and canine distemper virus than those from larger state parks. Exposure was associated with dog sex and age, lack of health care and the number of people in the households. Remarkably, factors linked to free-ranging behaviour of dogs were associated with the exposure for all pathogens detected. Conclusions According to identified associations, reducing viral pathogen exposure in dogs will require inhibiting dog’s movements and access to nearby forests and villages and improving veterinary assistance. Promoting dog vaccination and population control through sterilization around protected areas is also necessary. The study provides support for preventive management actions aimed to protect the health of rural dogs, and consequently of Atlantic Forest’s wild carnivores.

Cancer remains one of the world's most devastating diseases with millions of fatalities and new cases every year. In this work, we attempted to develop a facile "enzyme-free" fluoroimmunoassay based on the novel nanoconjugates composed of CdS quantum dots (QDs) as the fluorescent inorganic core and an antibody-modified polysaccharide as the organic shell, modeling their possible application for the in vitro diagnosis of non-Hodgkin lymphoma (NHL) cancer. Chitosan was conjugated with an anti-CD20 polyclonal antibody (pAbCD20) by the formation of covalent amide bonds. In the sequence, these chitosan-antibody conjugates were utilized as direct ligands for the surface biofunctionalization of CdS QDs (CdS/chitosan-pAbCD20) using a single-step colloidal process in aqueous medium at room temperature. The most relevant physico-chemical properties of these nanoconjugates were assessed by morphological and spectroscopic techniques. The results indicated that CdS nanocrystals were produced with an average diameter of 2.5 nm and with cubic zinc blende crystalline nanostructure. The CdS-immunoconjugates (CdS/chitosan-pAbCD20) presented colloidal hydrodynamic diameter (HD) of 15.0 ± 1.2n m. In addition, the results evidenced that the "enzyme-free" QD-linked immunosorbent assay (QLISA) was effective for the in vitro detection against the antigen CD20 (aCD20) based on fluorescent behavior of the CdS nanoconjugates. Moreover, the CdS-immunoconjugates were successfully used for fluorescence bioimaging of NHL cancer cells. Finally, the cell viability results using different cell cultures based on LDH, MTT and Resazurin bio-assays have demonstrated no cytotoxicity of the new CdS-chitosan bioconjugates relative to the standard controls. Thus, CdS conjugates may offer a promising platform for the future development of in vitro and in vivo applications for the detection and diagnosis of NHL cancer cells.

Despite undeniable advances in medicine in recent decades, cancer is still one of the main challenges faced by scientists and professionals in the health sciences as it remains one of the world's most devastating diseases with millions of fatalities and new cases every year. Thus, in this work, we endeavored to synthesize and characterize novel multifunctional immunoconjugates composed of quantum dots (QDs) as the fluorescent inorganic core and antibody-modified polysaccharide as the organic shell, focusing on their potential applications for in vitro diagnosis of non-Hodgkin lymphoma (NHL) cancer tumors. Chitosan was covalently conjugated with anti-CD20 polyclonal antibody (pAbCD20) via formation of amide bonds between amines and carboxyl groups. In the sequence, these biopolymer-antibody immunoconjugates were utilized as direct capping ligands for biofunctionalization of CdS QDs (CdS/chitosan-pAbCD20) using a single-step process in aqueous medium at room temperature. The nanostructures were characterized by UV-vis spectroscopy, photoluminescence spectroscopy (PL), FTIR, and transmission electron microscopy (TEM) with selected area electron diffraction. The TEM images associated with the UV-vis optical absorption results indicated formation of ultrasmall nanocrystals with average diameters in the range of 2.5-3.0 nm. Also, the PL results demonstrated that the immunoconjugates exhibited "green" fluorescent activity under ultraviolet excitation. Moreover, using in vitro laser light scattering immunoassay (LIA), the QDs/immunoconjugates have shown binding affinity against antigen CD20 (aCD20) expressed by lymphocyte-B cancer cells. In summary, innovative fluorescent nanoimmunoconjugate templates were developed with promising perspectives to be used in the future for detection and imaging of cancer tumors.

The maned wolf, Chrysocyon brachyurus, is an endangered Neotropical canid that survives at low population densities. Diseases are a potential threat for its conservation but to date have been poorly studied. We performed clinical evaluations and investigated the presence of infectious diseases through serology and coprologic tests on maned wolves from Galheiro Natural Private Reserve, Perdizes City, Minas Gerais State, southeastern Brazil. Fifteen wolves were captured between 2003 and 2008. We found high prevalences of antibody to canine distemper virus (CDV; 13/14), canine parvovirus (CPV; 4/14), canine adenovirus type 2 (13/14), canine coronavirus (5/11), canine parainfluenza virus (5/5), and Toxoplasma gondii (6/8), along with Ancylostomidae eggs in all feces samples. Antibodies against Leishmania sp. were found in one of 10 maned wolves, and all samples were negative for Neospora caninum. Evidence of high exposure to these viral agents was also observed in unvaccinated domestic dogs from neighboring farms. High prevalence of viral agents and parasites such as CDV, CPV, and Ancylostomidae indicates that this population faces considerable risk of outbreaks and chronic debilitating parasites. This is the first report of exposure to canine parainfluenza virus in Neotropical free-ranging wild canids. Our findings highlight that canine pathogens pose a serious hazard to the viability of maned wolves and other wild carnivore populations in the area and emphasize the need for monitoring and protecting wildlife health in remaining fragments of the Cerrado biome.

The aim of this study was to evaluate Porcine parvovirus (PPV) and Porcine circovirus 2 (PCV2) infection in dams and their offspring and the role of antibody protection on these infections. Sera were collected from gilts and sows by venipuncture and from umbilical cord of newborn pre-suckle piglets for the detection of PCV2 and PPV antibodies by immunoperoxidase monolayer and haemmaglutination inhibition assays, respectively. Gilts and sows sera were submitted to viral detection by PCR, as well as heart, lung, tonsil and lymph nodes samples from stillborn and mummified fetuses. High antibody titers before artificial insemination (AI) (>5.120 and >2.560 UHA for PCV2 and PPV, respectively), were found associated with viremia and fetal exposure for both PCV2 and PPV, respectively, in gilts and sows, regardless of pregnancy stage. These infections resulted in litters with mummified, stillborn, as well as seropositive and viable newborns. These findings bring new evidence about the lack of antibody protection against PCV2 and PPV infections in dams, indicating that more studies are necessary about the role of humoral response against both pathogens.

CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerais CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior FINEP - Financiadora de Estudos e Projetos, Financiadora de Estudos e Projetos Neste trabalho foi realizado o design, a síntese e a caracterização de membranas de hidrogéis híbridos à base de derivado de celulose funcionalizado com carboximetil (CMC), com dois graus de substituição (DS = 0,77 e 1,22), reticulados quimicamente pelo ácido cítrico (CA) e modificados, separadamente, com polietilenoglicol (PEG), incorporados com nanopartículas de prata (AgNPs) e bioconjugado com droga anticâncer, doxorrubicina (DOX). Os resultados demonstraram que os hidrogéis produzidos à base de CMC apresentaram comportamento superabsorvente com propriedades moduladas pelo grau de substituição do polímero, pelo teor de ácido cítrico e pela adição do PEG, das AgNPs e da DOX. A formação da estrutura reticulada ocorreu especialmente pela reação dos grupos hidroxilas da CMC com o ácido cítrico e os hidrogéis de CMC, CMC-PEG e CMCAgNPs apresentaram comportamento não-citotóxico. A adição de PEG levou à uma maior reticulação da rede polimérica na mesma direção do aumento da concentração do reticulante ácido cítrico (CA) e afetou drasticamente as propriedades nanomecânicas do material. Os híbridos de CMC-AgNPs apresentaram atividade antibacteriana eficaz contra patógenos gram positivos (Staphylococcus aureus) e contra as cepas gramnegativas (Escherichia coli e Pseudomonas aeruginosa). Nos estudos com bioconjugados polímero-droga, utilizando hidrogel de CMC com dois graus de substituição (DS = 0,77 e 1,22) e o fármaco cloridrato de doxorrubicina foi formada ligação covalente amida por interação dos grupos aminos da DOX com grupos carboxílicos da CMC, que foi confirmada com a caracterização por espectroscopia de FTIR. Os hidrogéis de CMC conjugados com doxorrubicina apresentaram a possibilidade de controlar a liberação da droga em função do grau de substituição da CMC e formação da ligação covalente droga-polímero, resultando, inclusive em uma liberação mais lenta para as células normais, permitindo uma redução dos efeitos agudos em células não-tumorais. Portanto, neste trabalho foram desenvolvimentos hidrogéis com características físicoquímicas, mecânicas e biológicas compatíveis para a utilização como biomateriais para potenciais aplicações no tratamento de feridas e regeneração epitelial e ainda com a possibilidade de incorporação de propriedades antibacterianas e antitumorais. This study focused on the design, synthesis and comprehensive characterization of environmentally friendly hydrogel membranes based on carboxymethyl cellulose (CMC) for wound dressing and skin repair substitutes. These new CMC hydrogels were prepared with two degrees of functionalization (DS = 0.77 and 1.22) and chemically crosslinked with citric acid (CA) for tuning their properties. Additionally, CMC-based hybrids were obtained by blending with polyethylene glycol (PEG) and nanocomposites with antibacterial and antitumor properties were synthesized combining CMC and silver nanoparticles (AgNPs) and by conjugation of doxorubicin (DOX) with CMC polymer, respectively. The results demonstrated that superabsorbent hydrogels (SAP) were produced which was significantly dependent on the concentration CA crosslinker, the DS of CMC, the addition of PEG as network modifier, the presence of AgNPs and DOX chemotherapeutic. The spectroscopical characterizations indicated that the mechanism of CA crosslinking was mostly associated with the chemical reaction with CMC hydroxyl groups and the CMC-based hydrogels (CMC, CMC-PEG and CMC-AgNPs) were cytocompatible considering the in vitro cell viability responses. In addition, PEG played an important role on the formation of a hybrid polymeric network with very distinct morphological and nanomechanical features. CMC–AgNP nanohybrids demonstrated highly effective antibacterial activity against gram-positive multi-resistant wound/skin pathogens (Staphylococcus aureus) and moderate effect towards gramnegative strains (Escherichia coli and Pseudomonas aeruginosa). The carbohydrate-based prodrug composed of CMC bioconjugated with DOX by covalent amide bonds demonstrated the effect of CMC hydrogel network structure with distinct degree of substitution regarding to the process of bioconjugation and on tailoring the DOX release kinetics in vitro and the cytotoxicity towards melanoma cancer cells in vitro. Therefore, SAP hydrogels were designed and produced with properties that are tunable through the extension of crosslinking and degree of substitution of carboxymethyl groups of the cellulose backbone. To this end, they are envisioned as promising hydrogels with key properties for assisting skin wound healing and regeneration, offering promising perspectives for skin disease applications associated with antibacterial activity and topical chemotherapy of melanoma.