Tag-mediated fractionation of yeast ribosome populations proves the monomeric organization of the eukaryotic ribosomal stalk structure

The analysis of the not well understood composition of the stalk, a key ribosomal structure, in eukaryotes having multiple 12 kDa P1/P2 acidic protein components has been approached using these proteins tagged with a histidine tail at the C-terminus. Tagged Saccharomyces cerevisiae ribosomes, which contain two P1 proteins (P1 alpha and P1 beta) and two P2 proteins (P2 alpha and P2 beta), were fractionated by affinity chromatography and their stalk composition was determined. Different yeast strains expressing one or two tagged proteins and containing either a complete or a defective stalk were used. No indication of protein dimers was found in the tested strains. The results are only compatible with a stalk structure containing a single copy of each one of the four 12 kDa proteins per ribosome. Ribosomes having an incomplete stalk are found in wild-type cells. When one of the four proteins is missing, the ribosomes do not carry the three remaining proteins simultaneously, containing only two of them distributed in pairs made of one P1 and one P2. Ribosomes can carry two, one or no acidic protein pairs. The P1 alpha/P2 beta and P1beta/P2 alpha pairs are preferentially found in the ribosome, but they are not essential either for stalk assembly or function.     

Gene expression,protein profiling,and chemotactic activity of infrapatellar fat pad mesenchymal stem cells in pathologies of the knee joint

The infrapatellar fat pad (IPFP) is a periarticular adipose knee tissue. This tissue contains a large number of mesenchymal stem cells (MSCs). In the present work, we wanted to study the IPFP MSCs and their relationship and differences in two groups, anterior cruciate ligament (ACL) ruptures knees and ostheoarthrosis (OA). The IPFP of 42 patients with OA or ACL rupture were analyzed. Isolation, primary culture, and a genetic and proteomic study of MSCs from IPFP were performed. Gene expression of IL-6, tumor necrosis factor (TNF), IL-8, HSPA1A (Hsp70), CXCL10, RANTES, MMP1, MMP3, TIMP1, and BMP7 was analyzed by real-time quantitative polymerase chain reaction (RT-qPCR). We analyzed MSCs from from 12 diferents patients in two cellular pools (6 from AO disease and 6 from ALC rupture to form two cell pool), for the iTRAQ Proteomic Assay. The conditional media were used in quantitative analysis of MSC soluble factors by Luminex and for de migration assay. A higher gene expression of IL-6, TNF, CXCL10, RANTES, and MMP1 and OPG in MSCs from OA versus ACL (p < 0.05) was observed. Conversely HSPA1A, TIMP1, and RANKL showed a significant lower expression in OA-MSCs (p < 0.05). In the secretome analysis, adipsin and visfantin levels in the supernatants from OA-MSCs were lower (p < 0.05) respect to ACL-MSCs. Also, the monocytic cells migrated two-folds in the presence of conditioned media from OA-MSCs patients versus patients with ACL-MSC. The infrapatellar pad should be considered as an adipose tissue capable of producing and excreting inflammatory mediators directly in the knee joint, influencing the development and progression of knee joint pathologies.     

Prevalence of Strongyloides stercoralis infection and associated clinical symptoms among schoolchildren living in different altitudes of Amhara National Regional State,northwest Ethiopia

BackgroundStrongyloides stercoralis is a parasite that causes strongyloidiasis in humans. It is prevalent in the tropics and sub-tropics where poor sanitation is a common problem. The true prevalence of S. stercoralis in Ethiopia is underestimated due to the lack of a “Gold” standard diagnostic method. Moreover, its prevalence across altitudinal gradient in Amhara Region has not been studied.MethodsA cross-sectional study was conducted among 844 schoolchildren in Amhara Region from April to December 2019. A stool sample was collected from each study participant and processed using formol ether concentration technique (FECT), spontaneous tube sedimentation technique (STST), Baermann concentration technique (BCT), agar plate culture (APC) and real-time polymerase chain reaction (RT-PCR). Data were entered using EpiData and analyzed by SPSS version 23 statistical software. Prevalence of S. stercoralis infection was determined using a single diagnostic technique and combination of techniques. Association of clinical variables with S. stercoralis infection was assessed by logistic regression and independent variables with p<0.05 were considered statistically significant.ResultsPrevalence of soil-transmitted helminths (STHs) and S. mansoni infections was 38.0% and 20.4%, respectively. Among STHs, the prevalence of hookworm infection was 32.8%. Prevalence of S. stercoralis infection was 39.0%, 28.8%, 10.9%, 10.3%, 4.0% and 2.0% by the respective, combinations of the five methods, RT-PCR, APC, BCT, STST and FECT. The highest prevalence rates, 48.2%, 45.0% and 41.1% of S. stercoralis were recorded in the age group of 12–14 years, males and rural dwellers, respectively. Prevalence rates of S. stercoralis infection in highland, semi-highland and lowland areas were 40.4%, 41.8% and 25.9%, respectively. Having abdominal pain (AOR = 2.48; 95% CI:1.65–3.72), cough (AOR = 1.63;95%CI:1.09–2.42), urticaria (AOR = 2.49;95%CI:1.50–4.01) and being malnourished (AOR = 1.44;95%:1.10–2.01) were significantly associated with strongyloidiasis.ConclusionPrevalence of S. stercoralis infection was high and varied across different altitudes in Amhara Region. Some clinical syndromes were found to be significantly associated with S. stercoralis infection. Therefore, proper diagnosis and preventive strategies against S. stercoralis infection are highly recommended to be devised and implemented in Amhara Region.     

Re-examination of global emerging patterns of ocean DMS concentration

During the last decade the number of seawater dimethylsulfide (DMS) concentration measurements has increased substantially. The importance this gas, emitted from the ocean to the atmosphere, may have in the cloud microphysics and hence in the Earth albedo and radiation budget, makes it necessary to accurately reproduce the global distribution. Recently, the monthly global DMS climatology has been updated taking advantage of the threefold increased size and better resolved distribution of the observations available in the DMS database. Here, the emerging patterns found with the previous versions of the database and climatology are explored with the updated versions. The statistical relationships between the seasonalities of DMS concentrations and other variables are re-examined. The positive correlation previously found between surface seawater DMS and the daily-averaged climatological solar radiation dose in the upper mixed layer of the open ocean is confirmed with both the updated DMS database and climatology. Re-examination of the latitudinal match-mismatch between the seasonalities of DMS and phytoplankton, represented by the chlorophyll a concentration, reveals that they are highly positively correlated in latitudes higher than 40°, but anti-correlated in the 20°–40° latitudinal bands of both hemispheres. Overall, these global emerging patterns provide key information to further understanding the factors that control the emission of volatile sulfur from the ocean. The large uncertainties associated with the methodologies used in global computations, however, call for caution in using these emerging patterns as predictive tools, and prompt to the design of time series and process-oriented studies aimed at testing the validity of the observed relationships.     

Analysis by LC/ESI-MS of iophenoxic acid derivatives and evaluation as markers of oral baits to deliver pharmaceuticals to wildlife

Iophenoxic acid and its derivatives (methyl, ethyl, and propyl) are organic chemicals used as markers in baiting campaigns to deliver vaccines, pharmaceuticals, contraceptives or poisons to wildlife. In this study we develop a method of detection of IPA derivatives by LC/ESI-MS (using butyl-IPA as internal standard) obtaining a limit of detection and quantification in wild boar (Sus scrofa) serum of 0.037 μg/ml and 0.123 μg/ml, respectively. The average recovery of IPA derivatives was 88% at levels >0.2 μg/ml, with coefficients of variation <15%. Wild boars in captivity were orally treated with 5 mg/kg b.w. (three adults) or 15 mg/kg b.w (two piglets and three adults) of methyl-, ethyl- and propyl-IPA and the serum levels of these were monitored during 18 months after dosing. Ethyl- and propyl-IPA were detected up to 18 months after a single oral dose in wild boar, especially at 15 mg/kg. Methyl-IPA was detected until 9 months after dosing. Half-lives of methyl-, ethyl- and propyl-IPA were (mean ± SD) 41 ± 5, 183 ± 85 and 165 ± 45 days, respectively. One control piglet not exposed to IPA, but housed in the same facility than treated animals showed detectable IPA levels in serum. Piglets born from mothers exposed to marked baits also showed detectable IPA levels in serum. The high persistence of Et- and Pr-IPA must be considered in the field trials, because the presence of the product at low levels in one animal may not reflect a real ingestion of the marked bait.     

Lack of evidence of paratuberculosis in wild canids from Southwestern Europe

Wild carnivores are at the top of the trophic chain. They are predators and carrion consumers, and thus, prone to come in contact with disease agents contaminating the environment or infecting live or dead animals. We hypothesized that wild canids could be used as sentinels for the detection of regions with higher Mycobacterium avium paratuberculosis (MAP) prevalence in wild and domestic animals. To test this hypothesis, we set up an ELISA to test 262 wolf (Canis lupus) and fox (Vulpes vulpes) sera for MAP-specific antibodies and processed a subset of samples for culture (n = 61), MAP-specific PCR (15) and histopathology (14). In wolves, the optical density (OD) values in the ELISA were continuously distributed. Ten fox sera (4%) had OD readings of over twice the mean, suggesting contact with mycobacteria. However, all samples tested by PCR were negative for both IS900 and ISMAP02 sequences, and samples cultured for MAP yielded no growth. No visible paratuberculosis or tuberculosis-compatible lesions were recorded. On histopathological examination, no lesions compatible with mycobacterial diseases were observed. These results suggest that wild canids show little or no evidence of paratuberculosis and are unlikely to be useful sentinels for the detection of MAP in Southwestern Europe.

     

Beta-Amyloid Impairs Reelin Signaling

Reelin is a signaling protein increasingly associated with the pathogenesis of Alzheimer’s disease that relevantly modulates tau phosphorylation. We have previously demonstrated that β-amyloid peptide (Aβ) alters reelin expression. We have now attempted to determine whether abnormal reelin triggered by Aβ will result in signaling malfunction, contributing to the pathogenic process. Here, we show that reelin forms induced by β-amyloid are less capable of down-regulating tau phosphorylation via disabled-1 and GSK3β kinase. We also demonstrate that the scaffold protein 14-3-3 that increases tau phosphorylation by modulating GSK3β activity, is up-regulated during defective reelin signaling. Binding of reelin to its receptor, mainly ApoER2 in the brain, relays the signal into the cell. We associate the impaired reelin signaling with inefficiency of reelin in forming active homodimers and decreased ability to bind efficiently to its receptor, ApoER2. More remarkably, reelin from Alzheimer cortex shows a tendency to form large complexes instead of homodimers, the active form for signaling. Our results suggest that reelin expression is altered by Aβ leading to impaired reelin signaling.     

Six recommendations for improving monitoring of diseases shared with wildlife: examples regarding mycobacterial infections in Spain

Monitoring is needed to identify changes in disease occurrence and to measure the impact of intervention. Using mycobacterial diseases as an example, we discuss herein the pros and cons of the current Spanish Wildlife Disease Surveillance Scheme providing suggestions for monitoring relevant diseases shared with wildlife in other regions facing similar challenges. Six points should be considered. This includes: (1) making sure the disease is properly monitored in the relevant domestic animals or even in humans; (2) also making sure that background information on wildlife population ecology is available to maximize the benefits of the monitoring effort; (3) selecting the appropriate wildlife hosts for monitoring, while being flexible enough to incorporate new ones if research suggests their participation; (4) selecting the appropriate methods for diagnosis and for time and space trend analysis; (5) deciding which parameters to target for monitoring; and finally (6) establishing a reasonable sampling effort and a suitable sampling stratification to ensure detecting changes over time and changes in response to management actions. Wildlife disease monitoring produces knowledge that benefits at least three different agencies, namely, animal health, public health and conservation, and these should combine efforts and resources. Setting up stable, comprehensive and accurate schemes at different spatial scales should become a priority. Resources are always a limiting factor, but experience shows that combined, cross-collaborative efforts allow establishing acceptable schemes with a low enough cost to be sustainable over time. These six steps for monitoring relevant shared diseases can be adapted to many other geographical settings and different disease situations.