Evaluación in vitro de Dos Fármacos de Uso Veterinario frente a Patógenos Causantes de Otitis Externa en Perros

The aim of this study was to evaluate the in vitro effect of two drugs of frequent use in veterinary practice against microorganisms isolated after treatment in 27 dogs with otitis externa. Various isolates were obtained from five dogs: two Pseudomonas aeruginosa, three Staphylococcus intermedius, and three yeasts of the genus Malassezia. The level of effectiveness of the antimicrobial drugs was determined by the method of Minimum Inhibitory Concentration (MIC). Gentamicin (3 mg/ml) and clotrimazole (10 mg/ml) solutions were prepared. Bacteria and yeast were brought to a concentration of 1x106 microorganism/ml. In ELISA plates, 150 μl of each bacteria or yeast and 150 μl of gentamicin or clotrimazole was added. Two repetitions and three replicates of each microorganism were considered in the study. As controls, drugs plus water and microorganisms plus water were used, and the volume adjusted to 300 μl each. Growth conditions in the spectrophotometer were 35 °C/10 rpm/24 h, where the growth kinetics of the microorganisms were measured at 660 OD. Results showed that gentamicin at a dose of 3 mg/ml causes an adequate growth inhibition of the bacteria, whereas clotrimazole can be used in the case of otitis caused by yeasts (M. pachidermatis), but at concentrations above 14 mg/ml.El objetivo del presente estudio fue evaluar el efecto in vitro de dos fármacos de uso veterinario frente a microorganismos aislados post-tratamiento en 27 perros con otitis externa. Se aislaron dos cepas de Pseudomonas aeruginosa, tres de Staphylococcus intermedius y tres levaduras del género Malassezia de cinco perros. El nivel de efectividad de los antimicrobianos se determinó por el método de Concentración Inhibitoria Mínima (CIM). Se prepararon soluciones de gentamicina (3 mg/ml) y de clotrimazol (10 mg/ml). Las bacterias y levaduras se llevaron a una concentración de 1x106 microorganismos/ml. En las placas de ELISA se colocó 150 µl de cada bacteria o levadura y 150 µl de gentamicina o clotrimazol. Se hicieron dos repeticiones y tres réplicas de cada microorganismo. Para los controles, se utilizaron los fármacos más agua y microorganismos más agua, ajustados a 300 µl c/u. Las condiciones de crecimiento en el espectrofotómetro fueron de 35 ºC /10 rpm/24 h, donde cada 2 h se midió la cinética de crecimiento del microorganismo a 660 de densidad óptica (DO). Se encontró que la gentamicina en una dosis de 3 mg/ml, produce una inhibición del crecimiento adecuado de las bacterias, en tanto que el clotrimazol podría emplearse en el caso de otitis causadas por levaduras (M. pachidermatis), pero en concentraciones superiores a 14 mg/ml

Relación entre quimerismo xx/xy y el fenotipo pseudohermafrodita masculino en porcinos.

La causa genética del pseudohermafroditismo no está bien dilucidada, sin embargo se han reportado distintos casos de pseudohermafroditas masculinos los cuales en la mayoría de los casos se han tratado de explicar por efectos hormonales sobre las gónadas en formación durante el desarrollo embrionario. Además se ha explorado poco la relación de este fenotipo con la constitución genómica de los organismos que presentan la disfunción sexual. En el presente trabajo se encontró una fuerte relación entre el quimerismo cromosómico XX/XY y el fenotipo pseudohermafrodita masculino exhibido por dos ejemplares de porcinos Landrace X Largewhite similar a lo encontrado en freemartinismo de bovinos

Resurgence of Vaccine-Preventable Diseases in Venezuela as a Regional Public Health Threat in the Americas.

Venezuela's tumbling economy and authoritarian rule have precipitated an unprecedented humanitarian crisis. Hyperinflation rates now exceed 45,000%, and Venezuela's health system is in free fall. The country is experiencing a massive exodus of biomedical scientists and qualified healthcare professionals. Reemergence of arthropod-borne and vaccine-preventable diseases has sparked serious epidemics that also affect neighboring countries. In this article, we discuss the ongoing epidemics of measles and diphtheria in Venezuela and their disproportionate impact on indigenous populations. We also discuss the potential for reemergence of poliomyelitis and conclude that action to halt the spread of vaccine-preventable diseases within Venezuela is a matter of urgency for the country and the region. We further provide specific recommendations for addressing this crisis

Latitude dictates plant diversity effects on instream decomposition

Running waters contribute substantially to global carbon fluxes through decomposition of terrestrial plant litter by aquatic microorganisms and detritivores. Diversity of this litter may influence instream decomposition globally in ways that are not yet understood. We investigated latitudinal differences in decomposition of litter mixtures of low and high functional diversity in 40 streams on 6 continents and spanning 113 degrees of latitude. Despite important variability in our dataset, we found latitudinal differences in the effect of litter functional diversity on decomposition, which we explained as evolutionary adaptations of litter-consuming detritivores to resource availability. Specifically, a balanced diet effect appears to operate at lower latitudes versus a resource concentration effect at higher latitudes. The latitudinal pattern indicates that loss of plant functional diversity will have different consequences on carbon fluxes across the globe, with greater repercussions likely at low latitudes

Venezuela's humanitarian crisis, resurgence of vector-borne diseases, and implications for spillover in the region.

In the past 5-10 years, Venezuela has faced a severe economic crisis, precipitated by political instability and declining oil revenue. Public health provision has been affected particularly. In this Review, we assess the impact of Venezuela's health-care crisis on vector-borne diseases, and the spillover into neighbouring countries. Between 2000 and 2015, Venezuela witnessed a 359% increase in malaria cases, followed by a 71% increase in 2017 (411 586 cases) compared with 2016 (240 613). Neighbouring countries, such as Brazil, have reported an escalating trend of imported malaria cases from Venezuela, from 1538 in 2014 to 3129 in 2017. In Venezuela, active Chagas disease transmission has been reported, with seroprevalence in children (<10 years), estimated to be as high as 12·5% in one community tested (n=64). Dengue incidence increased by more than four times between 1990 and 2016. The estimated incidence of chikungunya during its epidemic peak is 6975 cases per 100 000 people and that of Zika virus is 2057 cases per 100 000 people. The re-emergence of many vector-borne diseases represents a public health crisis in Venezuela and has the possibility of severely undermining regional disease elimination efforts. National, regional, and global authorities must take action to address these worsening epidemics and prevent their expansion beyond Venezuelan borders

Study on multi-ELVES in the Pierre Auger Observatory

Since 2013, the four sites of the Fluorescence Detector (FD) of the Pierre Auger Observatory record ELVES with a dedicated trigger. These UV light emissions are correlated to distant lightning strikes. The length of recorded traces has been increased from 100 μs (2013), to 300 μs (2014-16), to 900 μs (2017-present), to progressively extend the observation of the light emission towards the vertical of the causative lightning and beyond. A large fraction of the observed events shows double ELVES within the time window, and, in some cases, even more complex structures are observed. The nature of the multi-ELVES is not completely understood but may be related to the different types of lightning in which they are originated. For example, it is known that Narrow Bipolar Events can produce double ELVES, and Energetic In-cloud Pulses, occurring between the main negative and upper positive charge layer of clouds, can induce double and even quadruple ELVES in the ionosphere. This report shows the seasonal and daily dependence of the time gap, amplitude ratio, and correlation between the pulse widths of the peaks in a sample of 1000+ multi-ELVES events recorded during the period 2014-20. The events have been compared with data from other satellite and ground-based sensing devices to study the correlation of their properties with lightning observables such as altitude and polarity

A search for ultra-high-energy photons at the Pierre Auger Observatory exploiting air-shower universality

The Pierre Auger Observatory is the most sensitive detector to primary photons with energies above ∼0.2 EeV. It measures extensive air showers using a hybrid technique that combines a fluorescence detector (FD) with a ground array of particle detectors (SD). The signatures of a photon-induced air shower are a larger atmospheric depth at the shower maximum (X$_{max}$) and a steeper lateral distribution function, along with a lower number of muons with respect to the bulk of hadron-induced background. Using observables measured by the FD and SD, three photon searches in different energy bands are performed. In particular, between threshold energies of 1-10 EeV, a new analysis technique has been developed by combining the FD-based measurement of X$_{max}$ with the SD signal through a parameter related to its muon content, derived from the universality of the air showers. This technique has led to a better photon/hadron separation and, consequently, to a higher search sensitivity, resulting in a tighter upper limit than before. The outcome of this new analysis is presented here, along with previous results in the energy ranges below 1 EeV and above 10 EeV. From the data collected by the Pierre Auger Observatory in about 15 years of operation, the most stringent constraints on the fraction of photons in the cosmic flux are set over almost three decades in energy