A Simulated Intermediate State for Folding and Aggregation Provides Insights into ΔN6 β2-Microglobulin Amyloidogenic Behavior

A major component of ex vivo amyloid plaques of patients with dialysis-related amyloidosis (DRA) is a cleaved variant of β2-microglobulin (ΔN6) lacking the first six N-terminal residues. Here we perform a computational study on ΔN6, which provides clues to understand the amyloidogenicity of the full-length β2-microglobulin. Contrary to the wild-type form, ΔN6 is able to efficiently nucleate fibrillogenesis in vitro at physiological pH. This behavior is enhanced by a mild acidification of the medium such as that occurring in the synovial fluid of DRA patients. Results reported in this work, based on molecular simulations, indicate that deletion of the N-terminal hexapeptide triggers the formation of an intermediate state for folding and aggregation with an unstructured strand A and a native-like core. Strand A plays a pivotal role in aggregation by acting as a sticky hook in dimer assembly. This study further predicts that the detachment of strand A from the core is maximized at pH 6.2 resulting into higher aggregation efficiency. The structural mapping of the dimerization interface suggests that Tyr10, His13, Phe30 and His84 are hot-spot residues in ΔN6 amyloidogenesis

Description of Methicillin-resistant Staphylococcus pseudintermedius from canine pyoderma in Minas Gerais state, Brazil

ABSTRACT Methicillin-resistant Staphylococcus pseudintermedius (MRSP) is of worldwide concern in veterinary medicine. The identification of resistant strains is necessary for proper treatment and the prevention of its propagation among animals. This study aimed to identify S. pseudintermedius isolated from canine pyoderma and evaluate their resistance profiles. Lesions from 25 dogs with pyoderma were sampled. Bacterial isolates were subjected to phenotypic and genotypic analysis for identification of the causative agent. S. pseudintermedius isolates were subjected to SmaI macrorestriction analysis and PFGE for genetic grouping, and PCR to identify the presence of the mecA gene. Their resistance profiles against 12 antimicrobials were also assessed. According to the microbiological analysis, 70 of the 75 isolates obtained were S. pseudintermedius. The isolates presented PFGE patterns, with similarity varying between 84.6 and 100%, and were grouped into 19 clusters. Despite a high frequency of mecA-positive isolates (66 out 70), only 12 presented resistances to oxacillin. Multi-resistance was identified in 29 isolates. The high frequency of MRSP isolated in this study highlights the relevance of identifying resistant strains to lead proper clinical treatment. Keywords: Staphylococcus pseudintermedius, canine pyoderma, mecA, PFGE, antimicrobial resistance RESUMO Staphylococcus pseudintermedius meticilina-resistente (MRSP) é de preocupação mundial na medicina veterinária. A identificação de cepas resistentes é necessária a um tratamento adequado e à prevenção d

Precision restoration: a necessary approach to foster forest recovery in the 21st century

We thank S. Tabik, E. Guirado, and Garnata Drone SL for fruitful debates about the application of remote sensing and artificial intelligence in restoration. E. McKeown looked over the English version of the manuscript. Original drawings were made by J. D. Guerrero. This work was supported by projects RESISTE (P18-RT-1927) from the Consejeria de Economia, Conocimiento, y Universidad from the Junta de Andalucia, and AVA201601.19 (NUTERA-DE I), DETECTOR (A-RNM-256-UGR18), and AVA2019.004 (NUTERA-DE II), cofinanced (80%) by the FEDER Program. F.M.-R. acknowledges the support of the Agreement 4580 between OTRI-UGR and the city council of La Zubia. We thank an anonymous reviewer for helpful comments that improved the manuscript.Forest restoration is currently a primary objective in environmental management policies at a global scale, to the extent that impressive initiatives and commitments have been launched to plant billions of trees. However, resources are limited and the success of any restoration effort should be maximized. Thus, restoration programs should seek to guarantee that what is planted today will become an adult tree in the future, a simple fact that, however, usually receives little attention. Here, we advocate for the need to focus restoration efforts on an individual plant level to increase establishment success while reducing negative side effects by using an approach that we term “precision forest restoration” (PFR). The objective of PFR will be to ensure that planted seedlings or sowed seeds will become adult trees with the appropriate landscape configuration to create functional and self-regulating forest ecosystems while reducing the negative impacts of traditional massive reforestation actions. PFR can take advantage of ecological knowledge together with technologies and methodologies from the landscape scale to the individual- plant scale, and from the more traditional, low-tech approaches to the latest high-tech ones. PFR may be more expensive at the level of individual plants, but will be more cost-effective in the long term if it allows for the creation of resilient forests able to providemultiple ecosystemservices. PFR was not feasible a few years ago due to the high cost and low precision of the available technologies, but it is currently an alternative that might reformulate a wide spectrum of ecosystem restoration activities.Junta de Andalucia P18-RT-1927European Commission AVA201601.19 A-RNM-256-UGR18 AVA2019.004OTRI-UGR 4580city council of La Zubia 458

Fifth European Dirofilaria and Angiostrongylus Days (FiEDAD) 2016

Peer reviewe

Mini-FLOTAC for the diagnosis of Eimeria infection in goats: An alternative to McMaster

Caprine coccidiosis is responsible for remarkable economic losses. Diagnosis must therefore take into account a number of epidemiological and clinical factors supported by laboratory investigations. The detection of Eimeria oocysts and the determination of oocysts per gram of faeces (OPG) require a trustworthy oocyst count technique. Mini-FLOTAC is a new apparatus from the FLOTAC family, which was designed for optimal examination of faecal sample suspensions in each flotation chamber (total volume = 2 mL) and which permits a maximum magnification of 400x. Faecal samples from sixteen goats reared in an intensive goat farm were qualitatively (simple flotation) and quantitatively analyzed. A comparison between McMaster (McM) and Mini-FLOTAC was carried out, by performing 288 different readings. Eimeria arloingi, E. caprovina and E. ninakohlyakimovae were the most prevalent species. The mean OPG detected by Mini-FLOTAC was higher than the values observed with McMaster techniques (P0.05) but lower than those resulted from McM 0.3 mL. Thereby, the present study suggests that the Mini-FLOTAC is a promising technique for detecting and counting Eimeria spp. in goat faeces

Staphylococcus aureus undergoes major transcriptional reorganization during growth with Enterococcus faecalis in milk

Previous studies have demonstrated the antagonistic potential of lactic acid bacteria (LAB) present in raw milk microbiota over Staphylococcus aureus, albeit the molecular mechanisms underlying this inhibitory effect are not fully understood. In this study, we compared the behavior of S. aureus ATCC 29213 alone and in the presence of a cheese-isolated LAB strain, Enterococcus faecalis 41FL1 in skimmed milk at 30 °C for 24 h using phenotypical and molecular approaches. Phenotypic analysis showed the absence of classical staphylococcal enterotoxins in co-culture with a 1.2-log decrease in S. aureus final population compared to single culture. Transcriptional activity of several exotoxins and global regulators, including agr, was negatively impacted in co-culture, contrasting with the accumulation of transcripts coding for surface proteins. After 24 h, the number of transcripts coding for several metabolite responsive elements, as well as enzymes involved in glycolysis and acetoin metabolism was increased in co-culture. The present study discusses the complexity of the transcriptomic mechanisms possibly leading to S. aureus attenuated virulence in the presence of E. faecalis and provides insights into this interspecies interaction in a simulated food context

Growth and conformation changes in the young Lusitano horse: evaluation from birth to one year of age

Nowadays, there is a rising interest in the Lusitano breed as a sport horse. Besides the suggested relationship between growth rate and skeletal development, a better understanding of growing patterns could contribute for an accurate estimation of nutritional requirements in the growing horse. Therefore, the main objective of this study was to evaluate growth and development in Lusitano foals, from birth to one year of age, under extensive management conditions in Portugal. Thirty five foals from three stud farms were monthly weighed and withers height (WH), girth (G) and cannon circumference (CC) were measured. Average age at weaning was 7 mo (209±5d). Quadratic models were best fitted to describe the variation of body weight (BW), G, WH and CC. The effect of farm was significant for BW, G, and CC (P<0.0001), suggesting a management influence. Estimated BW at 7 and 12 mo of age in the three groups, varied between 211.1-253.8 kg and 274.6 327.7 kg, respectively, representing 42.2-50.8 % and 54.9-65.5 % of Lusitano mature BW (500kg). ADG until weaning varied between 0.786-0.888 kg/d, decreasing afterwards in the post-weaning period to 0.258-0.493 kg/d. Weight gain between birth and weaning represents 71.5-80.9 % of total weight gain until 12 mo of age. Estimated values for WH, G and CC at 12 mo of age varied between 135.4-140.9 cm, 145.4-157.5 cm and 16.7-19.0 cm, respectively. These results indicate a similar growth pattern to those described in other sport light breeds when submitted to moderate feeding levels, during the first year of life.vo