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The bovine respiratory disease (BRD) complex is a multifactorial and multietiological disease entity described in all geographic regions of Brazil. This brief review discusses aspects related to epidemiology, etiologic agents, clinical and pathological manifestations, and challenges in the diagnosis of BRD in Brazil. The main infectious disease agents associated with respiratory outbreaks in cattle from Brazil are bovine alphaherpesvirus type 1, bovine viral diarrhea virus, bovine respiratory syncytial virus, and Mycoplasma bovis. Ovine gammaherpesvirus-2 and HoBi-like pestivirus have been associated with the development of pneumonia in adult cattle and calves, respectively in Brazil, and should be considered as possible causes of BRD. Additionally, studies using epidemiological data, histopathological and molecular associations with morbidity and mortality should be carried out in Brazil, to demonstrate the real impacts of BRD on livestock. O complexo da doença respiratória bovina (DRB) é uma enfermidade multifatorial e multietiológica descrita em todas as regiões geográficas do Brasil. Essa breve revisão discute os aspectos relacionados epidemiologia, aos agentes etiológicos, as manifestações clínicas e patológicas e os desafios no diagnóstico da DRB no Brasil. Os principais agentes associados a surtos respiratórios brasileiros são: alfaherpesvírus bovino tipo 1, vírus da diarreia viral bovina, vírus sincicial respiratório bovino e Mycoplasma bovis. Gammaherpesvirus-ovino tipo-2 e HoBi-like pestivírus foram associados ao desenvolvimento de pneumonia em bovinos adultos e bezerros no país, respectivamente, e devem ser considerados como possíveis agentes no desenvolvimento da DRB. Adicionalmente, mais estudos utilizando dados epidemiológicos, associação histopatológica e molecular com morbidade e mortalidade devam ser realizados no Brasil, para demonstrar os verdadeiros efeitos de DRB em bovinos confinados.

217 p.-60 fig.-16 tab.-anexos., [EN]Nowadays, antibiotic resistance is one of the most urgent global health issues to be tackled. Among the infective bacteria, Gram-negative ones are the main causative agents of nosocomial infections, causing an important death burden, partly due to anti-microbial resistance. Currently, phage therapy research is experiencing a renaissance as a viable alternative or complement to common antimicrobial chemotherapy. Not only complete virion particles but also phage-derived products have a series of advantages over antibiotics. In particular, phage (endo)lysins are the phage-encoded proteins re-sponsible for bacterial host lysis and subsequent death due to their cell wall lytic activity. Lysins are being repurposed to be exogenously applied, in a purified form, against bac-teria, functioning as lytic antimicrobials, and thus are also called ‘enzybiotics’. Among the many advantages of enzybiotics, we may cite their lower chance to provoke resistance in the target bacteria and their versatility to be screened and engineered using bioinfor-matic and biotechnological tools. The current literature already proves that enzybiotics are efficient in killing Gram-positive bacteria. However, they have been deemed less effective against Gram-negative ones due to the presence of the outer membrane, which acts as a permeability barrier that prevents the access of the exogenously added enzyme to its target (the bacterial peptidoglycan). However, not only some recent engineering efforts have rendered lysins active against Gram-negative ‘from without’, but also there are reports of some lysins from phages that infect Gram-negatives that are intrinsically active against such bacteria. Such an intrinsic activity has been related to antimicrobial peptide-like regions located within the lysins. However, the evolutionary importance of those regions or their actual spread among the Gram-negative phage lysins is still un-known., In this thesis, a full design and development path towards the obtention of phage lysin-based antimicrobials especially directed against Gram-negative pathogens was in-vestigated. Firstly, a comprehensive database of lysin sequences was compiled and an-alysed to detect structural features related to the architecture of the corresponding bac-terial hosts. This analysis supported a widespread appearance of antimicrobial peptide-like subdomains within a relevant subpopulation of lysins from Gram-negative bacteria infecting phages. Making use of this database, a bioinformatic screening method was set up to predict antimicrobial peptide-like regions within the lysin sequences to select a set of enzybiotic candidates with the potential to interact (and disrupt) the Gram-negative outer membrane. In this way, an enzybiotic candidate, named Pae87, was selected for researching its intrinsic activity against Gram-negative pathogens, particularly Pseudo-monas aeruginosa, and to serve as a scaffold for the developing of efficient antimicrobialmolecules. A three-dimensional model of the protein with a bound peptidoglycan frag-ment was obtained in the course of this research. In this way, a putative substrate-bind-ing subdomain was identified within the very catalytic domain of the protein. In addition, the ability of Pae87 to bind and disrupt the Gram-negative outer membrane was proven, and it was related to a specific C-terminal region termed peptide P87. This peptide had an antimicrobial activity of its own, comparable to that of the full protein. Moreover, pep-tide P87 was enhanced by rational point mutation and thus the derived peptide P88 was obtained. Peptide P88 had a greater bactericidal efficiency against a similar range of Gram-negative bacteria but no dramatic increase in its cytotoxic effect against eukaryotic cells was found. In order to improve the therapeutic potential of P88, its synergistic ac-tivity with a set of antibiotics was tested. The peptide displayed a potent in vitro synergy when used in combination with various antibiotics with intracellular targets (namely mac-rolides, chloramphenicol, and tetracycline). Using this strategy, the effective concentra-tion of peptide (and antibiotics) was 4-fold reduced. Additionally, Pae87 activity was en-hanced by fusing it to a calcium-binding domain, giving rise to the Pae87F chimera. The calcium-binding activity was expected to improve the outer membrane-disrupting ability of the enzyme or its attachment to it by binding the cations that usually stabilize the outer membrane. In this way, the use of this kind of domain as enhancing modules for engi-neering enzybiotics was for the first time demonstrated., Finally, a strategy for the in vivo enzybiotics behaviour enhancement was developed. Since lysins in vivo half-life is known to be rather short (30-60 min), one of the currently explored approaches for enzybiotics administration is encapsulation and controlled re-lease. Based on the Streptococcus pneumoniae surface structure, which stands out for the presence of choline residues that serve as anchorage for physiologically relevant surface proteins, a chitosan-based polymer was designed. Such a polymer was grafted with diethylaminoethanol (DEAE) moieties which can act as a structural and functional analogue of choline. Therefore, the nanoparticles prepared with chitosan-DEAE were able to specifically bind choline-binding proteins. Due to this ability, the treatment of pneumococcal cultures with chitosan-DEAE nanoparticles provoked the chaining of the bacterial cells because of the competitive inhibition of housekeeping choline-binding pro-teins responsible for daughter cell separation. The chitosan-DEAE nanoparticles were thus also able to bind choline-binding enzybiotics, such as the antipneumococcal Cpl-711, and release it in a controlled manner, although with some cytotoxic effect against eukaryotic cells. Altogether, the results presented in this thesis investigate state-of-the-art tools and methods for the development of alternative, phage-derived antimicrobials to tackle some of the most relevant public health issues that we have to face in the years to come., [ES]Hoy en día, la resistencia a antibióticos es uno de los problemas de salud mundial más urgentes que deben abordarse. Entre las bacterias infecciosas, las Gram-negativas son los principales agentes causantes de infecciones nosocomiales, provocando una importante mortalidad, en parte debido a la resistencia a antimicrobianos. Actualmente, la investigación en terapia fágica está experimentando un renacimiento, entendida como alternativa viable o complemento de la quimioterapia antimicrobiana común. No solo las partículas fágicas completas sino también los productos derivados de fagos tienen una serie de ventajas sobre los antibióticos. En particular, las (endo)lisinas fágicas son las proteínas codificadas por los fagos que son responsables de la lisis y muerte bacteriana debido a su actividad enzimática que hidroliza la pared celular. Las lisinas se están re-utilizando para aplicarlas exógenamente en forma purificada contra bacterias, funcio-nando como antimicrobianos líticos y, por ello, también se denominan "enzibióticos". Entre las muchas ventajas de los enzibióticos, podemos citar su menor probabilidad de provocar resistencias en las bacterias diana y su versatilidad para ser detectadas y di-señadas utilizando herramientas bioinformáticas y biotecnológicas. La literatura actual prueba que los enzibióticos son altamente eficaces contra bacterias Gram-positivas. Sin embargo, se han considerado menos efectivos contra las Gram-negativas, debido a la presencia de la membrana externa que actúa como una barrera de permeabilidad que impide el acceso de la enzima exógenamente añadida a su diana (el peptidoglicano bacteriano). Sin embargo, no solo existen recientes estrategias de ingeniería de proteí-nas que han producido lisinas activas contra Gram negativas "desde fuera", sino que, además, hay ejemplos en la literatura de algunas lisinas de fagos que infectan a Gram-negativas que son intrínsecamente activas contra dichas bacterias. Tal actividad intrín-seca se ha relacionado con regiones similares a péptidos antimicrobianos presentes en las propias lisinas. Sin embargo, aún se desconoce la importancia evolutiva de esas regiones o su propagación real entre las lisinas de fagos que infectan a bacterias Gram-negativas., En esta tesis se ha llevado a cabo una estrategia completa de diseño y desarrollo de antimicrobianos basados en lisinas fágicas, especialmente dirigidos contra patógenos Gram-negativos. En primer lugar, se compiló y analizó una base de datos exhaustiva de secuencias de lisinas para detectar características estructurales relacionadas con la ar-quitectura de los hospedadores bacterianos correspondientes. En este análisis se ob-servó la presencia generalizada de subdominios similares a péptidos antimicrobianos dentro de una subpoblación relevante de lisinas de fagos de Gram-negativas. Haciendo uso de esta base de datos, se estableció un método de cribado bioinformático para predecir regiones similares a péptidos antimicrobianos dentro de las secuencias de lisi-nas con el objetivo de obtener un conjunto de candidatos a enzibióticos con el potencial de interactuar (y desestructurar) la membrana externa Gram-negativa. De esta manera, un enzibiótico candidato, denominado Pae87, fue seleccionado para investigar su acti-vidad intrínseca contra patógenos Gram-negativos, particularmente Pseudomonas ae-ruginosa, y para servir como base para el desarrollo de moléculas antimicrobianas efi-cientes. En el curso de la investigación, se obtuvo un modelo tridimensional de esta proteína conteniendo un fragmento de peptidoglicano unido. De esta manera, se identi-ficó un posible subdominio de unión a sustrato dentro del propio dominio catalítico de la proteína. Además, se demostró la capacidad de Pae87 para unirse y permeabilizar la membrana externa Gram-negativa, y esta actividad se relacionó con una región C-ter-minal específica denominada péptido P87. Este péptido mostró actividad antimicrobiana propia, comparable a la de la proteína completa. Además, el péptido P87 se potenció mediante mutaciones puntuales racionales y como resultado se obtuvo el péptido deri-vado P88. El péptido P88 mostró una mayor eficacia bactericida contra un rango similar de bacterias Gram-negativas, pero sin un aumento importante en su efecto citotóxico contra células eucariotas. Para mejorar el potencial terapéutico de P88, se probó su actividad sinérgica con un conjunto de antibióticos. El péptido mostró una potente siner-gia in vitro cuando se usó en combinación con varios antibióticos con dianas intracelu-lares (a saber, macrólidos, cloranfenicol y tetraciclina). Usando esta estrategia, la con-centración efectiva de péptidos (y antibióticos) se redujo 4 veces. La actividad de Pae87 también se mejoró, en este caso, fusionándola con un dominio de unión a calcio, dando lugar a la quimera Pae87F, esperando que la actividad de unión al calcio mejorara la capacidad de alteración de la membrana externa de la enzima o bien su unión a ella mediante la unión de los cationes que normalmente estabilizan la membrana externa. De esta forma, se ha demostrado por primera vez el posible uso de este tipo de dominios como módulos para mejorar enzibióticos mediante ingeniería de proteínas., Finalmente, se desarrolló una estrategia para mejorar el comportamiento in vivo de enzibióticos. Dado que se sabe que la vida media in vivo de las lisinas es bastante corta (30-60 min), uno de los enfoques actualmente explorados para la administración de en-zibióticos es su encapsulación y liberación controlada. Basándonos en la estructura su-perficial de Streptococcus pneumoniae, que destaca por la presencia de residuos de colina que sirven de anclaje para proteínas superficiales fisiológicamente relevantes, se diseñó un polímero a base de quitosano. Dicho polímero se derivatizó con dietila-minoetanol (DEAE) que pueden actuar como un análogo estructural y funcional de la colina. Por ello, las nanopartículas preparadas con quitosano-DEAE resultaron ser ca-paces de unir específicamente proteínas de unión a colina. Debido a esta capacidad, el tratamiento de cultivos neumocócicos con nanopartículas de quitosano-DEAE provocó el encadenamiento de las células bacterianas debido a la inhibición competitiva de las proteínas de unión a colina responsables de la separación de las células hijas. Las na-nopartículas de quitosano-DEAE también fueron capaces de unir enzibióticos de unión a colina, como el antineumocócico Cpl-711, y liberarlo de forma controlada, aunque con cierto efecto citotóxico en las células eucariotas.En conjunto, los resultados presentados en esta tesis proporcionan herramientas y métodos de última generación para el desarrollo de antimicrobianos alternativos deriva-dos de fagos para abordar algunos de los problemas de salud pública más relevantes que tendremos que enfrentar en los próximos años., Rroyecto SAF2017-88664-R del Ministerio de Economía y Competitividad (MINECO)

We have recently read the article by Chaung et al1 describing a case of SARS‐CoV‐2 and HCoV‐HKU1 coinfection. The HCoV‐HKU1 is also a member of the Betacoronavirus. In addition to other coronaviruses in different regions of the world, there is an increasing number of reports of coinfections in SARS‐CoV‐2/COVID‐19. Then, we would like to take the opportunity to discuss some of them,1-10 as there are not yet reviews on this emerging issue of COVID‐19. Currently, the evidence suggests that the coinfection rates between SARS‐CoV‐2 and other respiratory pathogens would be higher than initially expected, which represents a challenge for the diagnosis and treatment.

Este artículo tiene como objetivo principal estudiar las formas burlescas en el poema épico Argentina y conquista del Río de la Plata, de Martín del Barco Centenera. En primer lugar, se abordará el concepto «tradiciones discursivas» que permitirá un encuadre más amplio del texto. Luego, se comentará la presencia de la heteroglosia en la construcción del poema, la que se ejemplificará en el uso de anécdotas y de tres recursos humorísticos: la ironía dramática y la sátira, vinculadas con cierta retórica del infortunio, y el grotesco. Estas características se unen al estilo didáctico presente en el poema, todo lo cual produce un texto que aporta innovaciones a la propia tradición., The epidemiological and clinical management of cystic fibrosis (CF) patients suffering from acute pulmonary exacerbations or chronic lung infections demands continuous up dating of medical and microbiological processes associated with the constant evolution of pathogens during host colonization. In order to monitor the dynamics of these processes, it is essential to have expert systems capable of storing and subsequently extracting the information generated from different studies of the patients and microorganisms isolated from them. In this work we have designed and developed an on-line database based on an information system that allows to store, manage and visualize data from clinical studies and microbiological analysis of bacteria obtained from the respiratory tract of patients suffering from cysticfibrosis. The information system, named Cystic Fibrosis Cloud database is available on the http://servoy.infocomsa.com/cfc database site and is composed of a main database and a web-based interface, which uses Servoy’s product architecture based on Java technology. Although the CFC database system can be implemented as a local program for private use in CF centers, it can also be used, updated and shared by different users who can access the stored information in a systematic, practical and safe manner. The implementation of the CFC database could have a significant impact on the monitoring of respiratory infections, the prevention of exacerbations, the detection of emerging organisms, and the adequacy of control strategies forlung infections in CF patients., Centro de Investigación y Desarrollo en Fermentaciones Industriales

Para determinar la frecuencia de bacterias patógenas y su susceptibilidad antimicrobiana en muestras nasofaringeas de niños indígenas waraos de la comunidad María López, municipio Benítez del estado Sucre, con edades comprendidas entre 0 y 10 años, se procesaron 49 muestras recolectadas durante el período enero-marzo de 2008. La identificación bacteriana se realizó aplicando estudios bacteriológicos convencionales y la susceptibilidad antimicrobiana mediante el método de difusión en disco, siguiendo lineamientos del Instituto de Estándares de Laboratorios Clínicos (CLSI). Los resultados indicaron la presencia de Moraxella catarrhalis (28,6%), Streptococcus pneumoniae (26,5%), Staphylococcus aureus (14,3%) y Haemophilus influenzae (6,1%) en niños con y sin sintomatología. Las bacterias patógenas aisladas del tracto respiratorio superior fueron más frecuentes en el grupo de 0 a 5 años de edad, identificándose, principalmente, S. pneumoniae. Con respecto a la susceptibilidad antimicrobiana, S. pneumoniae mostró resistencia a tetraciclina (46,2%), trimetoprim-sulfametoxazol (38,5%), clindamicina (33,3%) y penicilina (23,1%). Los aislados de S. aureus expresaron sensibilidad a todos los antimicrobianos ensayados. El total de aislados de M. catarrhalis mostró resistencia a ampicilina y penicilina, además, resultaron productores de β-lactamasas. La presencia de bacterias patógenas a nivel nasofaríngeo en la población infantil, representa un riesgo para el desarrollo de infecciones severas del tracto respiratorio We collected and `processed 49 nasopharynx samples taken from indigenous Warao children 0-10 years old who lived at the María Lopez community of the Benitez Municipalit at Sucre State, with the purpose of determining the frequency of pathogenic bacteria and their antimicrobial sensitivity in samples collected from these children during the January-March 2008 period. The bacterial identification was obtained by applying conventional bacteriological methods and the antimicrobial sensitivity was determined by the disc diffusion method, following the guidelines of the Clinical Laboratory Standards Institute. The results showed presence of Moraxella catarrhalis (28.6%), Streptococcus pneumoniae (26.5%), Staphylococcus aureus (14.3%) and Haemophilus influenza (6.1%) in children with and without symptoms. The pathogenic bacteria isolated from the upper respiratory tract were more frequent in the 0-5 year old group and the most frequent identification was S. pneumoniae. Regarding antimicrobial sensitivity, S. pneumoniae was resistant to tetracycline (46.2%), trimetoprim-sulphametoxazol (38.5%), clindamicyn (33.3%) and penicillin (23.1%). The S. aureus isolates were sensitive to all the antimicrobials studied. All the M. catarrhalis isolates were resistant to ampicillin and penicillin and were also β-lactamase producers. The presence of pathogenic bacteria at the nasopharynx level in child populations signifies a risk for the development of severe respiratory tract infections

O exame bacteriológico é um dos principais parâmetros que auxiliam o diagnóstico e manuseio da infecção respiratória dos pacientes com Fibrose Cística (FC). Os microrganismos que colonizam e infectam o paciente fibrocístico determinam o tratamento, a qualidade de vida, as perspectivas para o transplante e a sua sobrevida global. A identificação precisa de patógenos respiratórios é essencial para o tratamento da infecção, seja como guia para o uso adequado de antibióticos por longos períodos para os pacientes com infecção bacteriana crônica ou para a aplicação adequada de medidas de controle de infecção. Embora exista um espectro limitado de patógenos respiratórios classicamente associados à doença respiratória na FC, um número crescente de microrganismos vem sendo reconhecido como potenciais agentes patogênicos. O espectro de patógenos em FC varia com a idade do paciente, mas, de uma forma geral, é bem estabelecido na literatura que existem quatro bactérias “clássicas”: Staphylococcus aureus, Haemophilus influenzae, Pseudomonas aeruginosa e o complexo B. cepacia (CBC). A maior sobrevida dos pacientes fibrocísticos, os quais são submetidos a ciclos repetidos de antibióticos, bem como o uso de novas metodologias de diagnóstico microbiológico contribuíram para o reconhecimento de patógenos emergentes ou “não-clássicos”, como Stenotrophomonas maltophilia, Achromobacter xylosoxidans e micobactérias nãotuberculosas (NMT) além de outros (Ralstonia sp, Cupriavidus sp, Pandoraea sp, Inqulinus limosus, Aspergillus sp , etc.). A principal bactéria envolvida com a doença respiratória em FC é a P.aeruginosa a qual durante o curso da infecção crônica pode apresentar variações fenotípicas peculiares aos pacientes fibrocísticos (crescimento em forma mucóide e em biofilme, hipermutabilidade, perda de flagelo, etc.) Portanto é necessário monitorar o surgimento de cepas de patógenos clássicos e não-clássicos principalmente aqueles mais resistentes aos antibióticos, como S. aureus resistentes a meticilina (MRSA) e P. aeruginosa resistente aos carbapenêmicos. Além disso é importante avaliar, através do exame bacteriológico, possíveis reduções de carga microbiana pulmonar, especialmente de P. aeruginosa e CBC, visto que a erradicação total destes patógenos é, invariavelmente, impossível em FC. The bacteriological culture is one of the main parameters that support the diagnosis and management of the respiratory infection in patients with cystic fibrosis (CF). The microorganisms that colonize and infect CF patients determine the treatment, quality of life, the lung transplant possibility and their overall survival. The accurate identification of respiratory pathogens is essential for the treatment of infection, either to guide the appropriate use of antibiotics for long periods to patients with chronic bacterial infection or to the proper implementation of infection control measures. Although there is a limited spectrum of respiratory pathogens classically associated with the respiratory disease in CF, an increasing number of microorganisms has been recognized as potential pathogens. The spectrum of pathogens in CF varies with the patients age but, in general, it is well established in the literature that there are four "classic" pathogens: Staphylococcus aureus, Haemophilus influenzae, Pseudomonas aeruginosa and the B. cepacia complex (Bcc). The longer survival of CF patients who undergo repeated cycles of antibiotics and the use of new methods of microbiological diagnosis contributed to the recognition of emerging or "non-classical" pathogens, such as Stenotrophomonas maltophilia, Achromobacter xylosoxidans, and nontuberculous mycobacteria (NMT) and other (Ralstonia sp, Cupriavidus sp, Pandoreae sp, Inqulinus limosus, Aspergillus sp, etc.) The main bacteria involved in respiratory disease in CF is P. aeruginosa which during the course of the chronic infection may present phenotypic variations peculiar to patients with cystic fibrosis (growth in the mucoid form and in biofilm, hipermutation, loss of flagella, etc.). Therefore it is necessary to monitor the emergence of classic and non-classical classics pathogens especially those resistant to antibiotics, such as S. aureus resistant to methicillin (MRSA) and P. aeruginosa resistant to carbapenems. Furthermore it is important to evaluate through the bacteriological examination, possible reductions in the pulmonary microbial load, especially P. aeruginosa and the Bcc, since the total eradication of these pathogens is invariably impossible in CF.