David Acosta Viana - Academia.edu (original) (raw)

Papers by David Acosta Viana

The ability to monitor vital signs in a hospital environment can be improved by information techn... more The ability to monitor vital signs in a hospital environment can be improved by information technology, specifically by IoT for healthcare. This technology allows services ranging from monitoring and analysis of vital signs in various environments and times of everyday life. This paper presents patient scenarios associated with data on heart rate, respiratory rate, blood pressure and peripheral oxygen saturation. By monitoring these data it is possible to calculate the risk score using the EWS (Early Warning Score), assisting health teams, reducing intervention times and improving data accuracy. The results obtained in this study demonstrate that individual monitoring and risk analysis, in hospital or other settings, besides improving the quality of care, can reduce the time to identify which patients are at risk, increasing the accuracy of the monitored signals.

Animals, 2020

The appearance of methicillin-resistant strains of Staphylococcus aureus (MRSA) in several animal... more The appearance of methicillin-resistant strains of Staphylococcus aureus (MRSA) in several animal species (including rabbits) has set off alarms for their capacity to act as reservoirs for this bacterium. This is especially important in wild animals given its epidemiological implications. The objectives of this study were to identify and characterize S. aureus, specifically MRSA, strains in wild lagomorph high-density areas. Ten hares and 353 wild rabbits from 14 towns with a high rabbit density in the Valencian region (eastern Spanish coast) were sampled. Swabs from the nasal cavity, ears, perineum and lesions (when present) were taken for microbiological studies. The detection of different genes and antibiotic susceptibility studies were also carried out. Of all the animals, 41.3% were positive for S. aureus, of which 63.3% were MRSA. Ears were the anatomical location with more S. aureus and MRSA strains. The more frequently identified MLST type was ST1945 (97.1%, 136/140). The me...

Anais Estendidos do XIX Simpósio Brasileiro de Computação Aplicada à Saúde (SBCAS), 2019

O Transtorno do Espectro Autista (TEA) está entre os problemas de saúde mental que mais prejudica... more O Transtorno do Espectro Autista (TEA) está entre os problemas de saúde mental que mais prejudicam o desenvolvimento infantil. Em geral, pessoas com o autismo precisam de suporte de habilidades linguísticas, comportamentais e sociais para serem bem-sucedidas. O presente trabalho buscou conhecer os principais desafios vivenciados por crianças com TEA e seus familiares/cuidadores, com base nas dificuldades relatadas pelos próprios familiares destas crianças e pela equipe multiprofissional que as acompanha. Os resultados encontrados podem subsidiar pesquisas futuras voltadas à atenuação dessas necessidades.

The following communication is an approach to the issues comprehending basic habitability in Afri... more The following communication is an approach to the issues comprehending basic habitability in African sub-Saharan cities, perceived in the experiences of urban planning, which may point out the prospective path of these developing territories. The subsequent synopsis-focused on the urban African experiences, from the post independence period up to today-consists in a brief reflection on the process which has led to the current context of survival and rupture, which defines the habitational compound of sub-Saharan Africa. Thusly, we will try to comment on the possible routes which may lead to a sustainable-and more effective-operational pattern, concerning the urban solutions apprehended as corner stones for a basic and more adequate habitability for this part of the African continent. Considering that the majority of the population who lives in peripheral neighbourhoods, lacking the basic infra-structures and urban services, organizes itself in spontaneous occupations, we can conclude that one of the contemporaneous African urban spaces' characteristics is, in fact, its rapid mutability that reports to an imprecise and gradually informal dynamism. If we regard the «shelter» factor as one of the main functions of the complex system formed by any urban African agglomerate, we will soon acknowledge the quite long list of problems caused by the disabilities concerning the housing in sub-Saharan Africa. If the current cultural paradigm does not evolve in a steadfast beat, and if we take under consideration the African regional urban developing, there is an obvious risk of increasing the territorial, social and cultural fragmentation, which will then cause an image of anachronism, asymmetry and lack of structure of the African landscape. More than merely a debate about the civilization archetype, these issues are about reflecting on experiences of urban planning that lead to the pondering on the possible responses to be given to the current issue, against the ill use of investment means and the wasting of synergies that the occupation models of the suburban frontiers imply nowadays, by the melting of the different communities.

Staphylococcus aureus es un patógeno muy versátil capaz de producir un amplio espectro de enferme... more Staphylococcus aureus es un patógeno muy versátil capaz de producir un amplio espectro de enfermedades en un gran número de hospedadores. En la especie cunícola produce una inflamación supurativa en prácticamente todos los órganos y localizaciones y, con frecuencia, una septicemia fatal. Se estudiaron 329 aislados de S. aureus procedentes de casos clínicos de 39 granjas cunícolas de la Comunidad Valenciana. Se realizó su tipado molecular, utilizando como criterio de selección el polimorfismo en la longitud de los fragmentos de restricción del producto de PCR del gen de la coagulasa, de la proteína A y del clumping factor B, obteniéndose 16 tipos diferentes de S. aureus. De estos aislados se seleccionaron 38 cepas representativas de cada tipo molecular y lesión de procedencia. Se analizaron por PCR diferentes genes implicados en la patogenia de S. aureus, comprobándose que cepas del mismo tipo molecular mostraban semejanza en los factores de patogenicidad, independientemente del tipo de lesión de procedencia, implicando una gran variabilidad. Esta falta de relación entre las lesiones producidas por las diferentes cepas y su arsenal genético podría indicarnos o bien que los factores de patogenicidad no tienen implicación directa en las lesiones o, lo más probable, que la inmunidad del hospedador juega un importante papel en la patogenia del proceso.

The Veterinary Journal, 2015

Staphylococcal infection causes substantial economic losses in commercial rabbit production syste... more Staphylococcal infection causes substantial economic losses in commercial rabbit production systems, and is associated with a wide variety of lesions, including chronic suppurative mastitis, which mainly affects breeding females. Most chronic staphylococcal infections in rabbits are caused by the ST121 lineage of Staphylococcus aureus, although other less common lineages, such as ST96 can also be involved. The aims of the present study were to characterise the host immune response in natural cases of mastitis in rabbits caused by S. aureus, to evaluate any relationship between peripheral and local immunity and to investigate the effect of different S. aureus genotypes on these immune responses. Adult multiparous female rabbits that were affected with chronic staphylococcal mastitis (n = 204) were enrolled into the study. Histological and immunohistochemical evaluations of mammary glands were undertaken, as well as flow cytometric analyses of blood. S. aureus isolates from the mammary glands were identified by multilocus sequence typing. Differences in the number of infiltrating cells were detected, depending on the type of pathology, with more immature lesions demonstrating greater cellularity, characterised by greater numbers of T lymphocytes, macrophages and plasma cells. A relationship was seen between the cells in blood and mammary tissues, the most notable being the positive correlation between monocytes and tissue macrophages. When glands were infected with ST96 strains, fewer granulocytes (P < 0.01) and greater numbers of B cells (P < 0.01), T cells (P < 0.001), CD4 + T cells (P < 0.001) and CD8 + T cells (P < 0.01) were detected, compared with mammary glands that were infected by ST121 strains of S. aureus.

Nature Genetics, 2015

This is a repository copy of A single natural nucleotide mutation alters bacterial pathogen host ... more This is a repository copy of A single natural nucleotide mutation alters bacterial pathogen host tropism.

The aim of this study was to determine how genetic type could affect the physiological and immune... more The aim of this study was to determine how genetic type could affect the physiological and immune status of commercial rabbits at weaning, as well as their performance and health during the growing period. The study was conducted on a total of 2904 young rabbits weaned at 30 days, belonging to three different genetic types (line H, founded for litter size at birth and selected for litter size at weaning during 17 generations; line LP, founded for reproductive longevity criteria and selected for litter size at weaning for 7 generations; and line R, founded and selected during 25 generations for average daily gain from the 4 th to the 9 th week of life). Two different diets were used during lactation. The two diets were both isoenergetic and isoproteic but their main energy source differed, being either animal fat (AF) or cereal starch (CS). Leukocyte subsets were characterised at weaning, and growing performance was studied until 58 days of age (feed intake, live weight, mortality by digestive disorders and morbidity) for both medicated and nonmedicated dietary versions. At weaning, young rabbits fed an AF lactating diet evidenced greater B lymphocyte count (+ 46%) than those fed a CS diet. Blood from LP rabbits had higher counts for total B, T CD5 + and CD8 + lymphocytes with respect to H and R (on av. +40, +57, +28, and +27%, respectively; P<0.05), and CD4 + lymphocytes, monocytes and granulocytes with respect to R (on av. +24, +32 and +44%, respectively; P<0.05) at weaning. LP line rabbits also showed lower mortality by digestive disorders (on av. −8 points of percentage) and morbidity (on av. −4 points) than those from H and R lines during the growing period (P<0.05). R animals presented higher feed intake and daily weight gain, and a lower feed conversion ratio than H and LP animals (on av. +16.7±2.7 g dry matter/day, +10.3±0.4 g/day and −0.22±0.04 g dry matter/g, respectively). In conclusion, the foundation of a line for reproductive longevity, which has been previously reported to give greater robustness (low environmental sensitivity) to their reproductive 3 stock, could have also conferred a greater immunological development at weaning to their offspring, as well as a better ability to confront digestive disorders as compared to other lines founded or selected exclusively for productive criteria.

Veterinary Immunology and Immunopathology, 2012

How selection for reproduction or foundation for longevity could have affected blood lymphocyte p... more How selection for reproduction or foundation for longevity could have affected blood lymphocyte populations of rabbit does under conventional and heat stress conditions.

Veterinary Record, 2007

The main reasons for culling adult rabbit does on two Spanish rabbit farms were investigated for ... more The main reasons for culling adult rabbit does on two Spanish rabbit farms were investigated for a year. The most important conditions were mastitis (33.3 per cent), followed by subcutaneous abscesses (9.9 per cent) and pyometra (8.7 per cent). Staphylococcus aureus infections were the most severe problem, the organism being isolated from 69.2 per cent of infected animals. Pasteurella species were more prevalent in cases of pyometra and pneumonia. Two strains of S aureus were identified by using polymorphism of the coagulase gene as the criterion. One of these strains was responsible for the majority of the staphylococcal infections and was isolated from several pathological processes.

The Veterinary Journal, 2011

Staphylococcal mastitis is one of the main reasons for culling adult does from commercial rabbitr... more Staphylococcal mastitis is one of the main reasons for culling adult does from commercial rabbitries. The aim of this study was describe the spectrum of gross and microscopic lesions in 178 cases of chronic staphylococcal mastitis in adult does and to determine whether there is a correlation between Staphylococcus aureus genotypes and pathology. On the basis of histopathology, chronic mastitis was differentiated into abscesses (66.3%), suppurative mastitis with a lobular pattern (7.9%), cellulitis (19.6%) and mixed lesions (6.2%). Pathological presentations were not related to S. aureus genotype.

Proceedings of the National Academy of Sciences, 2009

A surprising example of interspecies competition is the production by certain bacteria of hydroge... more A surprising example of interspecies competition is the production by certain bacteria of hydrogen peroxide at concentrations that are lethal for others. A case in point is the displacement of Staphylococcus aureus by Streptococcus pneumoniae in the nasopharynx, which is of considerable clinical significance. How it is accomplished, however, has been a great mystery, because H 2 O 2 is a very well known disinfectant whose lethality is largely due to the production of hyperoxides through the abiological Fenton reaction. In this report, we have solved the mystery by showing that H 2 O 2 at the concentrations typically produced by pneumococci kills lysogenic but not nonlysogenic staphylococci by inducing the SOS response. The SOS response, a stress response to DNA damage, not only invokes DNA repair mechanisms but also induces resident prophages, and the resulting lysis is responsible for H 2 O 2 lethality. Because the vast majority of S. aureus strains are lysogenic, the production of...

Molecular Microbiology, 2010

El artículo seleccionado no se encuentra disponible por ahora a texto completo por no haber sido ... more El artículo seleccionado no se encuentra disponible por ahora a texto completo por no haber sido facilitado todavía por el investigador a cargo del archivo del mismo.

Journal of Fish Diseases, 2013

Journal of Comparative Pathology, 2013

Introduction: Staphylococcus aureus is an adaptable and opportunistic pathogen capable of causing... more Introduction: Staphylococcus aureus is an adaptable and opportunistic pathogen capable of causing different lesions ranging from mild to severe depending on the infecting bacterial strain. Staphylococcal mastitis is one of the main causes of culling of adult rabbit does from commercial rabbitries. The objective of this study was to characterize the acute lesions in mammary glands infected with two different strains of S. aureus (A1/II1/d and B1/IV2/a).

Cornea, 2014

Staphylococcus aureus is the predominant pathogen that causes keratitis, and the rate of occurren... more Staphylococcus aureus is the predominant pathogen that causes keratitis, and the rate of occurrence of drug-resistant S. aureus is increasing. However, little is known about its clinical epidemiology in Japan. This study was designed to characterize the genotypes of methicillin-susceptible S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA) isolates from keratitis and healthy conjunctival sacs. Thirty keratitis isolates (19 MSSA and 11 MRSA) and 18 healthy conjunctival sac isolates (16 MSSA and 2 MRSA) obtained before cataract surgery were used. They were characterized by multilocus sequence typing. The prevalence of Panton-Valentine leukocidin was determined. In multilocus sequence typing analysis, ST5 and ST764 (ST5 variant) were the most frequently identified sequence types in MRSA strains from both keratitis and healthy conjunctival sacs. ST188 was the most frequently identified sequence type in the 19 MSSA isolates from keratitis (4 isolates, 21.1%), but was only identified in 1 of the 16 commensal MSSA strains. ST8 was found to be predominant among the 16 commensal MSSA strains (5 isolates, 31.3%). None of the isolates had Panton-Valentine leukocidin genes. MRSA isolates from keratitis and healthy conjunctival sacs may have similar genotypic characteristics, but certain clones occur more often among MSSA isolates from keratitis than among commensal MSSA strains. These results suggest that specific MSSA lineages that possess genotypic characteristics can more effectively cause keratitis.

XXXI Symposium de …, 2006

RESUMEN Staphylococcus aureus es el estafilococo más importante en la patología cunícola, ya que ... more RESUMEN Staphylococcus aureus es el estafilococo más importante en la patología cunícola, ya que se encuentra instaurado en la mayoría de explotaciones industriales originando una medicación, en ocasiones excesiva, que da lugar a multitud de resistencias en los ...

XXXI Symposium de …, 2006

RESUMEN La gestación abdominal se define como la implantación y desarrollo de un óvulo fertilizad... more RESUMEN La gestación abdominal se define como la implantación y desarrollo de un óvulo fertilizado o un embrión en la cavidad peritoneal. Se clasifica como gestación abdominal primaria, si no hay evidencia de rotura uterina, y como secundaria, cuando hay rotura ...

The ability to monitor vital signs in a hospital environment can be improved by information techn... more The ability to monitor vital signs in a hospital environment can be improved by information technology, specifically by IoT for healthcare. This technology allows services ranging from monitoring and analysis of vital signs in various environments and times of everyday life. This paper presents patient scenarios associated with data on heart rate, respiratory rate, blood pressure and peripheral oxygen saturation. By monitoring these data it is possible to calculate the risk score using the EWS (Early Warning Score), assisting health teams, reducing intervention times and improving data accuracy. The results obtained in this study demonstrate that individual monitoring and risk analysis, in hospital or other settings, besides improving the quality of care, can reduce the time to identify which patients are at risk, increasing the accuracy of the monitored signals.

Animals, 2020

The appearance of methicillin-resistant strains of Staphylococcus aureus (MRSA) in several animal... more The appearance of methicillin-resistant strains of Staphylococcus aureus (MRSA) in several animal species (including rabbits) has set off alarms for their capacity to act as reservoirs for this bacterium. This is especially important in wild animals given its epidemiological implications. The objectives of this study were to identify and characterize S. aureus, specifically MRSA, strains in wild lagomorph high-density areas. Ten hares and 353 wild rabbits from 14 towns with a high rabbit density in the Valencian region (eastern Spanish coast) were sampled. Swabs from the nasal cavity, ears, perineum and lesions (when present) were taken for microbiological studies. The detection of different genes and antibiotic susceptibility studies were also carried out. Of all the animals, 41.3% were positive for S. aureus, of which 63.3% were MRSA. Ears were the anatomical location with more S. aureus and MRSA strains. The more frequently identified MLST type was ST1945 (97.1%, 136/140). The me...

Anais Estendidos do XIX Simpósio Brasileiro de Computação Aplicada à Saúde (SBCAS), 2019

O Transtorno do Espectro Autista (TEA) está entre os problemas de saúde mental que mais prejudica... more O Transtorno do Espectro Autista (TEA) está entre os problemas de saúde mental que mais prejudicam o desenvolvimento infantil. Em geral, pessoas com o autismo precisam de suporte de habilidades linguísticas, comportamentais e sociais para serem bem-sucedidas. O presente trabalho buscou conhecer os principais desafios vivenciados por crianças com TEA e seus familiares/cuidadores, com base nas dificuldades relatadas pelos próprios familiares destas crianças e pela equipe multiprofissional que as acompanha. Os resultados encontrados podem subsidiar pesquisas futuras voltadas à atenuação dessas necessidades.

The following communication is an approach to the issues comprehending basic habitability in Afri... more The following communication is an approach to the issues comprehending basic habitability in African sub-Saharan cities, perceived in the experiences of urban planning, which may point out the prospective path of these developing territories. The subsequent synopsis-focused on the urban African experiences, from the post independence period up to today-consists in a brief reflection on the process which has led to the current context of survival and rupture, which defines the habitational compound of sub-Saharan Africa. Thusly, we will try to comment on the possible routes which may lead to a sustainable-and more effective-operational pattern, concerning the urban solutions apprehended as corner stones for a basic and more adequate habitability for this part of the African continent. Considering that the majority of the population who lives in peripheral neighbourhoods, lacking the basic infra-structures and urban services, organizes itself in spontaneous occupations, we can conclude that one of the contemporaneous African urban spaces' characteristics is, in fact, its rapid mutability that reports to an imprecise and gradually informal dynamism. If we regard the «shelter» factor as one of the main functions of the complex system formed by any urban African agglomerate, we will soon acknowledge the quite long list of problems caused by the disabilities concerning the housing in sub-Saharan Africa. If the current cultural paradigm does not evolve in a steadfast beat, and if we take under consideration the African regional urban developing, there is an obvious risk of increasing the territorial, social and cultural fragmentation, which will then cause an image of anachronism, asymmetry and lack of structure of the African landscape. More than merely a debate about the civilization archetype, these issues are about reflecting on experiences of urban planning that lead to the pondering on the possible responses to be given to the current issue, against the ill use of investment means and the wasting of synergies that the occupation models of the suburban frontiers imply nowadays, by the melting of the different communities.

Staphylococcus aureus es un patógeno muy versátil capaz de producir un amplio espectro de enferme... more Staphylococcus aureus es un patógeno muy versátil capaz de producir un amplio espectro de enfermedades en un gran número de hospedadores. En la especie cunícola produce una inflamación supurativa en prácticamente todos los órganos y localizaciones y, con frecuencia, una septicemia fatal. Se estudiaron 329 aislados de S. aureus procedentes de casos clínicos de 39 granjas cunícolas de la Comunidad Valenciana. Se realizó su tipado molecular, utilizando como criterio de selección el polimorfismo en la longitud de los fragmentos de restricción del producto de PCR del gen de la coagulasa, de la proteína A y del clumping factor B, obteniéndose 16 tipos diferentes de S. aureus. De estos aislados se seleccionaron 38 cepas representativas de cada tipo molecular y lesión de procedencia. Se analizaron por PCR diferentes genes implicados en la patogenia de S. aureus, comprobándose que cepas del mismo tipo molecular mostraban semejanza en los factores de patogenicidad, independientemente del tipo de lesión de procedencia, implicando una gran variabilidad. Esta falta de relación entre las lesiones producidas por las diferentes cepas y su arsenal genético podría indicarnos o bien que los factores de patogenicidad no tienen implicación directa en las lesiones o, lo más probable, que la inmunidad del hospedador juega un importante papel en la patogenia del proceso.

The Veterinary Journal, 2015

Staphylococcal infection causes substantial economic losses in commercial rabbit production syste... more Staphylococcal infection causes substantial economic losses in commercial rabbit production systems, and is associated with a wide variety of lesions, including chronic suppurative mastitis, which mainly affects breeding females. Most chronic staphylococcal infections in rabbits are caused by the ST121 lineage of Staphylococcus aureus, although other less common lineages, such as ST96 can also be involved. The aims of the present study were to characterise the host immune response in natural cases of mastitis in rabbits caused by S. aureus, to evaluate any relationship between peripheral and local immunity and to investigate the effect of different S. aureus genotypes on these immune responses. Adult multiparous female rabbits that were affected with chronic staphylococcal mastitis (n = 204) were enrolled into the study. Histological and immunohistochemical evaluations of mammary glands were undertaken, as well as flow cytometric analyses of blood. S. aureus isolates from the mammary glands were identified by multilocus sequence typing. Differences in the number of infiltrating cells were detected, depending on the type of pathology, with more immature lesions demonstrating greater cellularity, characterised by greater numbers of T lymphocytes, macrophages and plasma cells. A relationship was seen between the cells in blood and mammary tissues, the most notable being the positive correlation between monocytes and tissue macrophages. When glands were infected with ST96 strains, fewer granulocytes (P < 0.01) and greater numbers of B cells (P < 0.01), T cells (P < 0.001), CD4 + T cells (P < 0.001) and CD8 + T cells (P < 0.01) were detected, compared with mammary glands that were infected by ST121 strains of S. aureus.

Nature Genetics, 2015

This is a repository copy of A single natural nucleotide mutation alters bacterial pathogen host ... more This is a repository copy of A single natural nucleotide mutation alters bacterial pathogen host tropism.

The aim of this study was to determine how genetic type could affect the physiological and immune... more The aim of this study was to determine how genetic type could affect the physiological and immune status of commercial rabbits at weaning, as well as their performance and health during the growing period. The study was conducted on a total of 2904 young rabbits weaned at 30 days, belonging to three different genetic types (line H, founded for litter size at birth and selected for litter size at weaning during 17 generations; line LP, founded for reproductive longevity criteria and selected for litter size at weaning for 7 generations; and line R, founded and selected during 25 generations for average daily gain from the 4 th to the 9 th week of life). Two different diets were used during lactation. The two diets were both isoenergetic and isoproteic but their main energy source differed, being either animal fat (AF) or cereal starch (CS). Leukocyte subsets were characterised at weaning, and growing performance was studied until 58 days of age (feed intake, live weight, mortality by digestive disorders and morbidity) for both medicated and nonmedicated dietary versions. At weaning, young rabbits fed an AF lactating diet evidenced greater B lymphocyte count (+ 46%) than those fed a CS diet. Blood from LP rabbits had higher counts for total B, T CD5 + and CD8 + lymphocytes with respect to H and R (on av. +40, +57, +28, and +27%, respectively; P<0.05), and CD4 + lymphocytes, monocytes and granulocytes with respect to R (on av. +24, +32 and +44%, respectively; P<0.05) at weaning. LP line rabbits also showed lower mortality by digestive disorders (on av. −8 points of percentage) and morbidity (on av. −4 points) than those from H and R lines during the growing period (P<0.05). R animals presented higher feed intake and daily weight gain, and a lower feed conversion ratio than H and LP animals (on av. +16.7±2.7 g dry matter/day, +10.3±0.4 g/day and −0.22±0.04 g dry matter/g, respectively). In conclusion, the foundation of a line for reproductive longevity, which has been previously reported to give greater robustness (low environmental sensitivity) to their reproductive 3 stock, could have also conferred a greater immunological development at weaning to their offspring, as well as a better ability to confront digestive disorders as compared to other lines founded or selected exclusively for productive criteria.

Veterinary Immunology and Immunopathology, 2012

How selection for reproduction or foundation for longevity could have affected blood lymphocyte p... more How selection for reproduction or foundation for longevity could have affected blood lymphocyte populations of rabbit does under conventional and heat stress conditions.

Veterinary Record, 2007

The main reasons for culling adult rabbit does on two Spanish rabbit farms were investigated for ... more The main reasons for culling adult rabbit does on two Spanish rabbit farms were investigated for a year. The most important conditions were mastitis (33.3 per cent), followed by subcutaneous abscesses (9.9 per cent) and pyometra (8.7 per cent). Staphylococcus aureus infections were the most severe problem, the organism being isolated from 69.2 per cent of infected animals. Pasteurella species were more prevalent in cases of pyometra and pneumonia. Two strains of S aureus were identified by using polymorphism of the coagulase gene as the criterion. One of these strains was responsible for the majority of the staphylococcal infections and was isolated from several pathological processes.

The Veterinary Journal, 2011

Staphylococcal mastitis is one of the main reasons for culling adult does from commercial rabbitr... more Staphylococcal mastitis is one of the main reasons for culling adult does from commercial rabbitries. The aim of this study was describe the spectrum of gross and microscopic lesions in 178 cases of chronic staphylococcal mastitis in adult does and to determine whether there is a correlation between Staphylococcus aureus genotypes and pathology. On the basis of histopathology, chronic mastitis was differentiated into abscesses (66.3%), suppurative mastitis with a lobular pattern (7.9%), cellulitis (19.6%) and mixed lesions (6.2%). Pathological presentations were not related to S. aureus genotype.

Proceedings of the National Academy of Sciences, 2009

A surprising example of interspecies competition is the production by certain bacteria of hydroge... more A surprising example of interspecies competition is the production by certain bacteria of hydrogen peroxide at concentrations that are lethal for others. A case in point is the displacement of Staphylococcus aureus by Streptococcus pneumoniae in the nasopharynx, which is of considerable clinical significance. How it is accomplished, however, has been a great mystery, because H 2 O 2 is a very well known disinfectant whose lethality is largely due to the production of hyperoxides through the abiological Fenton reaction. In this report, we have solved the mystery by showing that H 2 O 2 at the concentrations typically produced by pneumococci kills lysogenic but not nonlysogenic staphylococci by inducing the SOS response. The SOS response, a stress response to DNA damage, not only invokes DNA repair mechanisms but also induces resident prophages, and the resulting lysis is responsible for H 2 O 2 lethality. Because the vast majority of S. aureus strains are lysogenic, the production of...

Molecular Microbiology, 2010

El artículo seleccionado no se encuentra disponible por ahora a texto completo por no haber sido ... more El artículo seleccionado no se encuentra disponible por ahora a texto completo por no haber sido facilitado todavía por el investigador a cargo del archivo del mismo.

Journal of Fish Diseases, 2013

Journal of Comparative Pathology, 2013

Introduction: Staphylococcus aureus is an adaptable and opportunistic pathogen capable of causing... more Introduction: Staphylococcus aureus is an adaptable and opportunistic pathogen capable of causing different lesions ranging from mild to severe depending on the infecting bacterial strain. Staphylococcal mastitis is one of the main causes of culling of adult rabbit does from commercial rabbitries. The objective of this study was to characterize the acute lesions in mammary glands infected with two different strains of S. aureus (A1/II1/d and B1/IV2/a).

Cornea, 2014

Staphylococcus aureus is the predominant pathogen that causes keratitis, and the rate of occurren... more Staphylococcus aureus is the predominant pathogen that causes keratitis, and the rate of occurrence of drug-resistant S. aureus is increasing. However, little is known about its clinical epidemiology in Japan. This study was designed to characterize the genotypes of methicillin-susceptible S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA) isolates from keratitis and healthy conjunctival sacs. Thirty keratitis isolates (19 MSSA and 11 MRSA) and 18 healthy conjunctival sac isolates (16 MSSA and 2 MRSA) obtained before cataract surgery were used. They were characterized by multilocus sequence typing. The prevalence of Panton-Valentine leukocidin was determined. In multilocus sequence typing analysis, ST5 and ST764 (ST5 variant) were the most frequently identified sequence types in MRSA strains from both keratitis and healthy conjunctival sacs. ST188 was the most frequently identified sequence type in the 19 MSSA isolates from keratitis (4 isolates, 21.1%), but was only identified in 1 of the 16 commensal MSSA strains. ST8 was found to be predominant among the 16 commensal MSSA strains (5 isolates, 31.3%). None of the isolates had Panton-Valentine leukocidin genes. MRSA isolates from keratitis and healthy conjunctival sacs may have similar genotypic characteristics, but certain clones occur more often among MSSA isolates from keratitis than among commensal MSSA strains. These results suggest that specific MSSA lineages that possess genotypic characteristics can more effectively cause keratitis.

XXXI Symposium de …, 2006

RESUMEN Staphylococcus aureus es el estafilococo más importante en la patología cunícola, ya que ... more RESUMEN Staphylococcus aureus es el estafilococo más importante en la patología cunícola, ya que se encuentra instaurado en la mayoría de explotaciones industriales originando una medicación, en ocasiones excesiva, que da lugar a multitud de resistencias en los ...

XXXI Symposium de …, 2006

RESUMEN La gestación abdominal se define como la implantación y desarrollo de un óvulo fertilizad... more RESUMEN La gestación abdominal se define como la implantación y desarrollo de un óvulo fertilizado o un embrión en la cavidad peritoneal. Se clasifica como gestación abdominal primaria, si no hay evidencia de rotura uterina, y como secundaria, cuando hay rotura ...