Controlling Coxiella burnetii in naturally infected sheep, goats and cows, and public health implications: a scoping review.

Q fever is a worldwide zoonotic disease which domestic ruminants are the main source of infection for humans. This scoping review summarizes the control measures currently available to reduce Coxiella burnetii (Cb) infection in naturally infected sheep, goat and cattle herds. A total of 28 articles were included in the review. A lack of methodological standardization was noted in the articles analyzed. The results indicated that long-term vaccination in cows reduces bacterial excretion in milk and environmental contamination. In small ruminants, the results of vaccination in terms of efficacy are variable. In goats, there is a reduction in bacterial excretion, unlike in sheep, where a long-term vaccination program is necessary to reduce bacterial excretion. Moreover, the high persistence of viable Cb in the environment means that control measures for sheep are needed for several years. The use of antibiotics as a control measure in cows and sheep was not found to reduce excretion. However, the combination of vaccination with antibiotic therapy appears to have positive effects in small ruminants in terms of controlling outbreaks of Q fever. Hygiene and biosecurity measures are the basic means for controlling Cb infection on ruminant farms and ensuring public health.

In Vitro Interaction between Mycoplasma agalactiae and Small Ruminants' Endogenous Bacterial Strains of Enterococcus spp. and Coagulase-Negative Staphylococcus.

Recently, an antimicrobial effect on Mycoplasma agalactiae (Ma), the main etiological agent of contagious agalactia (CA), was reported in vitro with strains of Enterococcus spp. from ovine and caprine milk. The aim of this work was to evaluate the interaction of Ma with the same Enterococcus spp. isolated from other anatomical locations (vagina) and other bacterial populations present in milk, such as coagulase-negative staphylococci (CNS). The vaginal Enterococcus strains and the raw milk CNS were isolated from sheep and goats. Experimental in vitro conditions were prepared to assess the growth of Ma with and without the presence of these strains. The selected vaginal strains were identified as Enterococcus (E.) hirae and E. mundtii, and the strains of CNS were identified as Staphylococcus petrasii. Different interactions of Ma with ovine and caprine wild vaginal strains of Enterococcus and dairy strains of CNS are described for the first time: Ma can grow exponentially during 15 h with the selected strains, although with certain strains, its optimal growth can be negatively affected (p < 0.05). The colonization and/or excretion of Ma could, therefore, be influenced by certain endogenous bacterial strains. Our results increase the knowledge about possible bacterial ecology dynamics surrounding CA.

[In the beginning it was zoonosis: One Health to combat this and future pandemics. SESPAS Report 2022]. / En el principio fue la zoonosis: One Health para combatir esta y futuras pandemias. Informe SESPAS 2022.

The new pandemic, COVID-19, highlighted the importance of the animal-human-environment interface in the emergence of zoonoses. The jump of the species barrier is considered a rare event although the number of emerging infectious diseases increased significantly in the second half of the 20th century. Most of them transmitted from wildlife to humans. Several elements can contribute to the emergence of zoonoses: human interaction on ecosystems, biodiversity loss, changes in land use, climate change, trade in or consumption of wildlife. There are different stages in the adaptation of an animal pathogen into a specialized human pathogen, varying from its presence in animals without human infection to a pathogen exclusive to humans. The history of zoonoses allows the identification of critical points for their control, as well as the identification of probable virus or bacteria involved in future pandemics. Concerning COVID-19, the knowledge of the possible reservoirs of SARS-CoV-2 contributed to decision-making during the pandemic. Therefore, and given the variety of scenarios that allow the jump of species barrier or the evolution of pathogens in a new host, One Health strategies for zoonosis emergence surveillance should be implemented.

Comparison of Commercial Enzyme-linked Immunosorbent Assays for Diagnosis of Contagious Agalactia Caused By Mycoplasma Agalactiae.

Introduction: Contagious agalactia (CA) is a disease affecting small ruminants with worldwide distribution and caused by several mycoplasmas, especially M. agalactiae. The main option for systematic diagnosis under monitoring control programmes is the enzyme-linked immunosorbent assay (ELISA) test. Material and Methods: This study was designed to appraise the performance of two commercial indirect ELISA tests using M. agalactiae p48 protein and one using total protein, for antibody detection in small ruminants after natural infection with different M. agalactiae strains. We carried out the test evaluation using sera of confirmed M. agalactiae-positive goats with clinical signs. In addition, test agreement was assessed by kappa between the three commercial ELISA tests. Results: All three ELISA tests showed high validity scores (Youden's J: 72.9-84%). The sensitivity values for the P48 protein-based tests were 76.9% and 84.6%, and was 79% for the total protein-based test. The specificity of all tests was 100%. In addition, between the total protein-based ELISA test and the other two ELISA tests based on the P48 protein, the agreement was substantial (kappa: 0.762-0.763) and the agreement between the latter two tests was almost perfect (kappa: 0.93). Conclusion: The validity parameters for all tests allowed their application for diagnostic purposes in lactating goats excreting M. agalactiae in milk and presenting clinical signs. The agreements show that any of these ELISA tests could be equally well used for diagnosis in programmes against CA.

Perceived Impact of the COVID-19 Lockdown on the Family Context of Foster and Non-Foster Families.

The COVID-19 pandemic and the resulting lockdown have had a far-reaching impact across all levels of society. In Spain, severe restrictions were placed on people's mobility, and leaving the home was only possible under special circumstances. This study analyzes the impact of lockdown on the family context of foster and non-foster families, focusing particularly on their levels of cohesion, adaptability, and perceived stress. It also examines a series of variables that may have influenced foster families' perceptions of their family context during lockdown. Data were gathered through an online survey that was completed by 347 individuals corresponding to 100 foster families and 247 non-foster families from different regions of Spain. Analyses were descriptive and exploratory in nature. The results appear to suggest that lockdown has had a greater impact on the family context of non-foster families. With respect to foster families' experiences of lockdown, variables such as loss of employment and having a child with special educational needs would seem to be important. For both types of families, lockdown has provided an opportunity to improve certain aspects of their family context. Given that further lockdowns of some degree may be necessary in the future, it is important to ensure that families have access to the psychoeducational resources they need to maintain, as far as possible, a positive family context.

Perceived stress, resources and adaptation in relation to the COVID-19 lockdown in Spanish foster and non-foster families.

The lockdown imposed as a result of the COVID-19 pandemic has placed unprecedented stress on families. The family is a key system in relation to child development, and when birth families are unable to meet their child's needs, foster carers become an important source of support in their development. The Double ABC-X Model of family stress and adaptation considers that a family's capacity to cope with stressful situations is influenced by pile-up of stressors, family resources and perception of the situation. Following this model, the study aimed to determine the impact of the COVID-19 lockdown on family stress and functioning. The sample comprised 347 Spanish adults (100 with foster families and 247 with non-foster families) who completed a survey during lockdown. The results showed that certain sociodemographic variables (gender, income, working from home, characteristics of the home and children with special educational needs) were associated with stressors during lockdown, perception of the lockdown, and family adaptation to stress during lockdown. Associations were also found between stressors, family resources, perception of lockdown, and family adaptation in foster and non-foster families, with the former having a more positive perception of the lockdown experience. The relevance of the results and their implications are discussed.

Energy-Efficient Wireless Communication Strategy for Precision Agriculture Irrigation Control.

In smart farming, precision agriculture irrigation is essential to reduce water consumption and produce higher crop yields. Closed-loop irrigation based on soil moisture measurements has demonstrated the capability to achieve a considerable amount of water savings while growing healthy crops. Automated irrigation systems are typically implemented over wireless sensor networks, where the sensing devices are battery-powered, and thus they have to manage energy constraints by implementing efficient communication schemas. Self-triggered control is an aperiodic sampling strategy capable of reducing the number of networked messages compared to traditional periodical sampling. In this paper, we propose an energy-efficient communication strategy for closed-loop control irrigation, implemented over a wireless sensor network, where event-driven soil moisture measurements are conducted by the sensing devices only when needed. Thereby, the self-triggered algorithm estimates the occurrence of the next sampling period based on the process dynamics. The proposed strategy was evaluated in a pecan crop field and compared with periodical sampling implementations. The experimental results show that the proposed adaptive sampling rate technique decreased the number of communication messages more than 85% and reduced power consumption up to 20%, while still accomplishing the system control objectives in terms of the irrigation efficiency and water consumption.

An Approach to the Use of Glycol Alkoxysilane-Polysaccharide Hybrids in the Conservation of Historical Building Stones.

Stone consolidants have been widely used to protect historical monuments. Consolidants and hydrophobic formulations based on the use of tetraethoxysilane (TEOS) and alkylalkoxysilanes as precursors have been widely applied, despite their lack of solubility in water and requirement to be applied in organic media. In the search for a "greener" alternative based on silicon that has potential use in this field, the use of tetrakis(2-hydroxyethyl)silane (THEOS) and tris(2-hydroxyethyl)methyl silane (MeTHEOS) as precursors, due their high water solubility and stability, is proposed in this paper. It is already known that THEOS and MeTHEOS possess remarkable compatibility with different natural polysaccharides. The investigated approach uses the water-soluble silanes THEOS-chitosan and MeTHEOS-chitosan as a basis for obtaining hybrid consolidants and hydrophobic formulations for the conservation of siliceous and calcareous stones. In the case of calcareous systems, their incompatibility with alkoxysilanes is known and is expected to be solved by the developed hybrid consolidant. Their application in the conservation of building stones from historical and archeological sites from Guanajuato, México was studied. The evaluation of the consolidant and hydrophobic formulation treatment was mainly conducted by determining the mechanical properties and contact angle measurements with satisfactory results in terms of the performance and compatibility with the studied stones.

Revisiting the System Silanes-Polysaccharides: The Cases of THEOS-Chitosan and MeTHEOS-Chitosan.

The glycol alkoxysilanes, tetrakis(2-hydroxyethyl)silane (THEOS), and tris(2-hydroxyethyl)methyl silane (MeTHEOS) are water soluble derivatives of tetraethoxysilane (TEOS) and methyltriethoxysilane (MeTEOS) and precursors of the system silane-chitosan reviewed in this work. The glycol modified alkoxysilanes are obtained by transesterification reaction of TEOS or MeTEOS with ethylene glycol. The reaction evolution is monitored by 29 Si NMR. It is possible to observe the formation of the various species of glycol alkoxysilanes in equilibrium as the reaction proceeds showing that the oligomers formation is favored at longer reaction times with the final product tendency to gel keeping the complete water solubility. The glycol alkoxysilanes are synthesized at moderated reaction conditions, by using the Piers-Rubinsztajn (PR) reaction. Additionally, it is already known that THEOS is compatible with different natural polysaccharides as chitosan and the same behavior has been demonstrated in this work for MeTHEOS. Several reports refer studies regarding the system THEOS-polysaccharides to synthesize hybrid materials. The system THEOS-chitosan is known but the characterization as well as the way silane-chitosan interact has not been studied in detail. In the present report, chemical evidence of the covalent interactions THEOS- and MeTHEOS-chitosan based on NMR studies (13 C and 29 Si) are presented as intended.

The relationship of counterfactual reasoning and false belief understanding: the role of prediction and explanation tasks

The relation between the prediction and explanation of the false belief task (FBT) with counterfactual reasoning (CFR) was explored. Fifty eight 3-5 year-olds received a prediction or an explanation FBT, a belief attribution task and some counterfactual questions of increasing difficulty. Linguistic comprehension was also controlled. CFR highly predicted FBT in the explanation version but not in the prediction one. Additionally, results in the explanation version indicate that CFR underlies achievements prior to the understanding of the representational mind and stimulates the explicitness of the mental domain. This study identifies the conditions under which CFR becomes a fundamental cognitive tool for social cognition. The results obtained contribute to the dialog between the two major theoretical approaches: theory-theory and simulation theory

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[Occupational exposure to influenza virus of the wild birds]. / Exposición ocupacional a los virus influenza de las aves silvestres.

Wild waterfowl are considered the main natural reservoir of influenza viruses and they have contributed to the reassortment of both pandemic viruses and viruses responsible for outbreaks of avian influenza in wild and domestic species. In order to determinate the factors involved, we reviewed the human cases of avian influenza related to the management of wild birds, the use of personal protective equipment, as well as the basis of surveillance programs of highly pathogenic avian influenza in wild birds in Spain. The direct transmission of influenza virus from wild birds to humans is a rare event. However, our epidemiological context is influenced by climate change and marked by the presence of migratory routes from territories where infection may be present. Thus and due to the clinical, economical and public health implications that such infections may have, the different groups exposed to wild birds (veterinarians, biologists, ornithologists, conservationists, field technicians, environmental officers, falconers, hunters, etc.) should know which are the possible sources of infection and how to handle the personal protective equipment. Besides, it is important that those groups know the current sanitary situation regarding avian influenza so they can consequently adapt their activities and employ proper protective measures, in addition to providing valuable information for surveillance programs.

Las aves acuáticas silvestres representan el principal reservorio natural de los virus influenza y han participado en el reordenamiento tanto de virus pandémicos como de los virus responsables de los brotes de gripe aviar en las especies domésticas y silvestres. Con el objetivo de conocer los determinantes implicados, en el presente trabajo se revisaron los casos humanos de influenza aviar asociados al manejo de avessilvestres y la utilización de los equipos de protección personal, así como las bases de la vigilancia de la influencia aviar altamente patógena en aves silvestres en España. Las evidencias existentes permiten concluir que la transmisión directa de virus influenza desde las aves silvestres al ser humano es un evento raro. No obstante, nuestro contexto epidemiológico se encuentra influido por el cambio climático y queda marcado por la presencia de rutas migratorias desde territorios donde la infección puede estar presente. Por ello, y ante las implicaciones clínicas, económicas y para la salud pública que dichas infecciones pueden tener, los diferentes colectivos expuestos a las aves silvestres (veterinarios, biólogos, ornitólogos, conservacionistas, técnicos de campo, agentes medioambientales, cetreros, cazadores, etc.) deberían conocer las posibles fuentes de contagio y manejar correctamente los equipos de protección personal. Al mismo tiempo, es importante que dichos grupos conozcan la situación sanitaria actualizada respecto a la influenza aviar, para adaptar sus actividades en consecuencia y poder aplicar las medidas de protección de forma proporcionada a la misma, amén de aportar una valiosa información para los programas de vigilancia.

Exposición ocupacional a los virus influenza de las aves silvestres / Occupational exposure to influenza virus of the wild birds

Las aves acuáticas silvestres representan el principal reservorio natural de los virus influenza y han participado en el reordenamiento tanto de virus pandémicos como de los virus responsables de los brotes de gripe aviar en las especies domésticas y silvestres. Con el objetivo de conocer los determinantes implicados, en el presente trabajo se revisaron los casos humanos de influenza aviar asociados al manejo de avessilvestres y la utilización de los equipos de protección personal, así como las bases de la vigilancia de la influencia aviar altamente patógena en aves silvestres en España. Las evidencias existentes permiten concluir que la transmisión directa de virus influenza desde las aves silvestres al ser humano es un evento raro. No obstante, nuestro contexto epidemiológico se encuentra influido por el cambio climático y queda marcado por la presencia de rutas migratorias desde territorios donde la infección puede estar presente. Por ello, y ante las implicaciones clínicas, económicas y para la salud pública que dichas infecciones pueden tener, los diferentes colectivos expuestos a las aves silvestres (veterinarios, biólogos, ornitólogos, conservacionistas, técnicos de campo, agentes medioambientales, cetreros, cazadores, etc.) deberían conocer las posibles fuentes de contagio y manejar correctamente los equipos de protección personal. Al mismo tiempo, es importante que dichos grupos conozcan la situación sanitaria actualizada respecto a la influenza aviar, para adaptar sus actividades en consecuencia y poder aplicar las medidas de protección de forma proporcionada a la misma, amén de aportar una valiosa información para los programas de vigilancia

Wild waterfowl are considered the main natural reservoir of influenza viruses and they have contributed to the reassortment of both pandemic viruses and viruses responsible for outbreaks of avian influenza in wild and domestic species. In order to determinate the factors involved, we reviewed the human cases of avian influenza related to the management of wild birds, the use of personal protective equipment, as well as the basis of surveillance programs of highly pathogenic avian influenza in wild birds in Spain. The direct transmission of influenza virus from wild birds to humans is a rare event. However, our epidemiological context is influenced by climate change and marked by the presence of migratory routes from territories where infection may be present. Thus and due to the clinical, economical and public health implications that such infections may have, the different groups exposed to wild birds (veterinarians, biologists, ornithologists, conservationists, field technicians, environmental officers, falconers, hunters, etc.) should know which are the possible sources of infection and how to handle the personal protective equipment. Besides, it is important that those groups know the current sanitary situation regarding avian influenza so they can consequently adapt their activities and employ proper protective measures, in addition to providing valuable information for surveillance programs

Escala de Comunicación autopercibida en la relación de pareja (CARP) / Scale of Self-perceived Communication in the Couple Relationship (SCCR)

Este estudio busca construir y validar la Escala de Comunicación autopercibida en la relación de pareja (CARP) con el fin de ofrecer un instrumento sencillo y útil. Participaron 620 personas que mantenían una relación de pareja. Para estudiar la estructura factorial de la escala se dividió aleatoriamente la muestra en dos submuestras, realizándose una validación cruzada mediante análisis factorial exploratorio (AFE) y análisis factorial confirmatorio (AFC). Asimismo, para comprobar que el modelo se mantenía estable al tener en cuenta la variable sexo, se repitió el análisis factorial confirmatorio con las submuestras de mujeres y de hombres y se aplicó un AFC Multigrupo para comprobar la invarianza factorial en función de esta variable. Se ha obtenido una escala de 8 ítems constituida por dos factores que explican el 46.6% de la varianza y que presenta una buena fiabilidad (alfa = .75), comprobándose la invarianza estricta en función del sexo. Esta escala puede ser útil en el campo de la detección, prevención e intervención en situaciones de conflicto entre la pareja

This study aims to design and validate the Scale of Self-perceived Communication in the Couple Relationship (SCCR) in order to provide a straightforward and useful instrument. 620 persons who were in a couple relationship took part in this study. The sample was divided randomly into two subsamples to study the factor structure of the scale, carrying out a cross-validation by using an exploratory factor analysis (EFA) and a confirmatory factor analysis (CFA). Also, and to verify that the model remained stable taking account of the variable gender, the confirmatory factor analysis was repeated with the women and men subsamples, and a multigroup CFA was carried out to check the factor invariance according to this variable An 8-items scale was obtained, made up with two factors explaining 46.6% of the variance who also reported a good reliability (alfa = .75), testing the strict invariance according to the gender. This scale might be useful in the field of detection, prevention and intervention of conflict situations in the couple relationship

[Zoonoses and occupational health in the veterinary profession]. / Zoonosis y salud laboral en la profesión veterinaria.

The veterinary profession implies a greater risk of infection by zoonotic pathogens than the overall population. The aim of the present work was to evaluate the impact of zoonoses on the occupational health of veterinarians reviewing the published surveys addressing this subject. Following these inquiries, between 4% and 64.3% of the surveyed professionals acknowledge to have suffered at least one zoonotic disease, and dermatophytosis is the most frequently described zoonosis. In addition, from a qualitative point of view, it is necessary to highlight the occurrence of different diseases of important clinical seriousness and the existence of infections by antimicrobial-resistant pathogens. Due to the absence of updated studies in Spain, the present work reflects on the need to recognize the health determinants associated to the veterinary profession within the characteristics of our labour market. The available data suggest that the occurrence of zoonoses as occupational diseases is underestimated in Spain. Therefore, performing surveys on occupational health, documenting and publishing cases and reviewing the risks and the impact of zoonotic diseases on the veterinary profession would contribute to the description and notification of such diseases on behalf of the healthcare administration and would also become an essential tool in occupational risk prevention.

La profesión veterinaria presenta mayor riesgo de infección frente a agentes patógenos de carácter zoonósico que la población general. Con el objetivo de valorar el impacto de las zoonosis, el presente trabajo revisa las encuestas publicadas sobre salud laboral en la profesión veterinaria. En dichas encuestas, el rango de profesionales que refieren haber padecido al menos una zoonosis oscila entre el 4% y el 64,3%, siendo la dermatofitosis la zoonosis comunicada con mayor frecuencia. Además, desde el punto de vista cualitativo, cabe destacar la comunicación de diferentes procesos de especial gravedad clínica, así como la existencia documentada de infecciones por agentes patógenos resistentes a los antimicrobianos. Dada la ausencia de estudios actualizados en España, se reflexiona sobre la necesidad de conocer los determinantes de salud asociados a las características del mercado laboral de la profesión en nuestro entorno. Los datos existentes sugieren que la consideración legal de enfermedad profesional para las zoonosis se encuentra infraestimada en nuestro país. Por todo ello, la realización de encuestas de salud laboral, la documentación y publicación de los casos, así como la revisión de los riesgos y el impacto de las zoonosis en la profesión veterinaria, pueden contribuir a la calificación y notificación de dichas enfermedades por parte de la administración sanitaria, al tiempo que suponen una herramienta fundamental en el ámbito de la prevención de riesgos laborales.

23S rRNA and L22 ribosomal protein are involved in the acquisition of macrolide and lincosamide resistance in Mycoplasma capricolum subsp. capricolum.

Mycoplasma capricolum subsp. capricolum (Mcc) is one of the causative agents of contagious agalactia, and antimicrobial therapy is the most commonly applied measure to treat outbreaks of this disease. Macrolides and lincosamides bind specifically to nucleotides at domains II and V of the 23S rRNA. Furthermore, rplD and rplV genes encode ribosomal proteins L4 and L22, which are also implicated in the macrolide binding site. The aim of this work was to study the relationship between mutations in these genes and the acquisition of macrolide and lincosamide resistance in Mcc. For this purpose, in vitro selected resistant mutants and field isolates were studied. This study demonstrates the appearance of DNA point mutations at the 23S rRNA encoding genes (A2058G, A2059G and A2062C) and rplV gene (Ala89Asp) in association to high minimum inhibitory concentration values. Hence, it proves the importance of alterations in 23S rRNA domain V and ribosomal protein L22 as molecular mechanisms responsible for the acquisition of macrolide and lincosamide resistance in both field isolates and in vitro selected mutants. Moreover, these mutations enable us to provide an interpretative breakpoint of antimicrobial resistance for Mcc at MIC 0.8 µg/ml.

Zoonosis y salud laboral en la profesión veterinaria / Zoonoses and occupational health in the veterinary profession

La profesión veterinaria presenta mayor riesgo de infección frente a agentes patógenos de carácter zoonósico que la población general. Con el objetivo de valorar el impacto de las zoonosis, el presente trabajo revisa las encuestas publicadas sobre salud laboral en la profesión veterinaria. En dichas encuestas, el rango de profesionales que refieren haber padecido al menos una zoonosis oscila entre el 4% y el 64,3%, siendo la dermatofitosis la zoonosis comunicada con mayor frecuencia. Además, desde el punto de vista cualitativo, cabe destacar la comunicación de diferentes procesos de especial gravedad clínica, así como la existencia documentada de infecciones por agentes patógenos resistentes a los antimicrobianos. Dada la ausencia de estudios actualizados en España, se reflexiona sobre la necesidad de conocer los determinantes de salud asociados a las características del mercado laboral de la profesión en nuestro entorno. Los datos existentes sugieren que la consideración legal de enfermedad profesional para las zoonosis se encuentra infraestimada en nuestro país. Por todo ello, la realización de encuestas de salud laboral, la documentación y publicación de los casos, así como la revisión de los riesgos y el impacto de las zoonosis en la profesión veterinaria, pueden contribuir a la calificación y notificación de dichas enfermedades por parte de la administración sanitaria, al tiempo que suponen una herramienta fundamental en el ámbito de la prevención de riesgos laborales

The veterinary profession implies a greater risk of infection by zoonotic pathogens than the overall population. The aim of the present work was to evaluate the impact of zoonoses on the occupational health of veterinarians reviewing the published surveys addressing this subject. Following these inquiries, between 4% and 64.3% of the surveyed professionals acknowledge to have suffered at least one zoonotic disease, and dermatophytosis is the most frequently described zoonosis. In addition, from a qualitative point of view, it is necessary to highlight the occurrence of different diseases of important clinical seriousness and the existence of infections by antimicrobial-resistant pathogens. Due to the absence of updated studies in Spain, the present work reflects on the need to recognize the health determinants associated to the veterinary profession within the characteristics of our labour market. The available data suggest that the occurrence of zoonoses as occupational diseases is underestimated in Spain. Therefore, performing surveys on occupational health, documenting and publishing cases and reviewing the risks and the impact of zoonotic diseases on the veterinary profession would contribute to the description and notification of such diseases on behalf of the healthcare administration and would also become an essential tool in occupational risk prevention

Molecular resistance mechanisms of Mycoplasma agalactiae to macrolides and lincomycin.

The extensive use of antimicrobials for disease control has caused a remarkable decrease in antimicrobial susceptibility of different animal mycoplasma species, including Mycoplasma agalactiae (M. agalactiae), the main causative agent of contagious agalactia. However, the molecular mechanisms behind M. agalactiae resistance to macrolides and lincomycin have not yet been elucidated. The aim of the present study was to investigate the association between minimum inhibitory concentration (MIC) values of different antimicrobials and mutations in the 23S rRNA gene and ribosomal proteins L4 and L22, analysing both field isolates (n=50) and in vitro selected resistant mutants of M. agalactiae. The obtained MIC results of the studied field isolates demonstrate an increasing development of tylosin resistance in this bacterium, in comparison to previous studies. Interestingly, predicted amino acid changes in L22 (Ser89Leu and Gln90Lys/His) were the first variations observed when MICs of M. agalactiae started to increase (tylosin MIC ≥0.8µg/ml), whereas mutations at positions 2058 or 2059 of domain V of the 23S rRNA gene appeared from MIC values of 1.6µg/ml. These results were consistent in both field isolates and in vitro selected mutants of M. agalactiae. Thus, although in other mycoplasma species resistance to macrolides and lincosamides had been mainly related to mutations in the 23S rRNA gene, this work demonstrates the role of alterations in ribosomal protein L22 in decreased susceptibility of M. agalactiae. Moreover, these mutations can be used as molecular markers to set an interpretative breakpoint of antimicrobial resistance for M. agalactiae.

Design and implementation of a control structure for quality products in a crude oil atmospheric distillation column.

In recent years, interest for petrochemical processes has been increasing, especially in refinement area. However, the high variability in the dynamic characteristics present in the atmospheric distillation column poses a challenge to obtain quality products. To improve distillates quality in spite of the changes in the input crude oil composition, this paper details a new design of a control strategy in a conventional crude oil distillation plant defined using formal interaction analysis tools. The process dynamic and its control are simulated on Aspen HYSYS® dynamic environment under real operating conditions. The simulation results are compared against a typical control strategy commonly used in crude oil atmospheric distillation columns.