An ancient testis-specific IQ motif-containing H gene regulates specific transcript isoform expression during spermatogenesis.

Spermatogenic cells express more alternatively spliced RNAs than most whole tissues; however, the regulation of these events remains unclear. Here, we have characterized the function of a testis-specific IQ motif-containing H gene (Iqch) using a mutant mouse model. We found that Iqch is essential for the specific expression of RNA isoforms during spermatogenesis. Using immunohistochemistry of the testis, we noted that Iqch was expressed mainly in the nucleus of spermatocyte and spermatid, where IQCH appeared juxtaposed with SRRM2 and ERSP1 in the nuclear speckles, suggesting that interactions among these proteins regulate alternative splicing (AS). Using RNA-seq, we found that mutant Iqch produces alterations in gene expression, including the clear downregulation of testis-specific lncRNAs and protein-coding genes at the spermatid stage, and AS modifications - principally increased intron retention - resulting in complete male infertility. Interestingly, we identified previously unreported spliced transcripts in the wild-type testis, while mutant Iqch modified the expression and use of hundreds of RNA isoforms, favouring the expression of the canonical form. This suggests that Iqch is part of a splicing control mechanism, which is essential in germ cell biology.

Adenylate kinase 9 is essential for sperm function and male fertility in mammals.

Despite passing routine laboratory tests for semen quality, bulls used in artificial insemination exhibit significant variation in fertility. Routine analysis of fertility data identified a dairy bull with extreme subfertility (10% pregnancy rate). To characterize the subfertility phenotype, a range of in vitro, in vivo, and molecular assays were carried out. Sperm from the subfertile bull exhibited reduced motility and severely reduced caffeine-induced hyperactivation compared to controls. Ability to penetrate the zona pellucida, cleavage rate, cleavage kinetics, and blastocyst yield after IVF or AI were significantly lower than in control bulls. Whole-genome sequencing from semen and RNA sequencing of testis tissue revealed a critical mutation in adenylate kinase 9 (AK9) that impaired splicing, leading to a premature termination codon and a severely truncated protein. Mice deficient in AK9 were generated to further investigate the function of the gene; knockout males were phenotypically indistinguishable from their wild-type littermates but produced immotile sperm that were incapable of normal fertilization. These sperm exhibited numerous abnormalities, including a low ATP concentration and reduced motility. RNA-seq analysis of their testis revealed differential gene expression of components of the axoneme and sperm flagellum as well as steroid metabolic processes. Sperm ultrastructural analysis showed a high percentage of sperm with abnormal flagella. Combined bovine and murine data indicate the essential metabolic role of AK9 in sperm motility and/or hyperactivation, which in turn affects sperm binding and penetration of the zona pellucida. Thus, AK9 has been found to be directly implicated in impaired male fertility in mammals.

Proteomics-based determination of double-stranded RNA interactome reveals known and new factors involved in Sindbis virus infection.

Viruses are obligate intracellular parasites, which depend on the host cellular machineries to replicate their genome and complete their infectious cycle. Long double-stranded (ds)RNA is a common viral by-product originating during RNA virus replication and is universally sensed as a danger signal to trigger the antiviral response. As a result, viruses hide dsRNA intermediates into viral replication factories and have evolved strategies to hijack cellular proteins for their benefit. The characterization of the host factors associated with viral dsRNA and involved in viral replication remains a major challenge to develop new antiviral drugs against RNA viruses. Here, we performed anti-dsRNA immunoprecipitation followed by mass spectrometry analysis to fully characterize the dsRNA interactome in Sindbis virus (SINV) infected human cells. Among the identified proteins, we characterized SFPQ (splicing factor, proline-glutamine rich) as a new dsRNA-associated proviral factor upon SINV infection. We showed that SFPQ depletion reduces SINV infection in human HCT116 and SK-N-BE(2) cells, suggesting that SFPQ enhances viral production. We demonstrated that the cytoplasmic fraction of SFPQ partially colocalizes with dsRNA upon SINV infection. In agreement, we proved by RNA-IP that SFPQ can bind dsRNA and viral RNA. Furthermore, we showed that overexpression of a wild-type, but not an RNA binding mutant SFPQ, increased viral infection, suggesting that RNA binding is essential for its positive effect on the virus. Overall, this study provides the community with a compendium of dsRNA-associated factors during viral infection and identifies SFPQ as a new proviral dsRNA binding protein.

Hyperparasitism in bat flies (Diptera: Streblidae): new records and interaction networks in the Neotropics.

Hyperparasitism is defined as the interaction where one parasite is infected by another parasite. In bat flies (Streblidae and Nycteribiidae), both hyperparasites and microparasites (bacteria, viruses, fungi, and arthropods such as mites) have been documented. Fungi belonging to the order Laboulbeniales are microscopic parasites of a wide diversity of arthropod hosts. Three genera exclusively target bat flies: Arthrorhynchus, which parasitizes species within Nycteribiidae in the Eastern Hemisphere, while genus Gloeandromyces and Nycteromyces parasitize Streblidae in the Western Hemisphere. Among the hyperparasitic arthropods, mites of family Neothrombidiidae, particularly the monospecific genus Monunguis, are known to parasitize bat flies. Here we present the first records of the hyperparasites Monunguis streblida and Gloeandromyces pageanus f. polymorphus parasitizing Streblidae bat flies in Colombia and a summary of these hyperparasitic interactions in the Neotropics. We detected fungi and mites parasitizing bat flies that were collected in the Magdalena River Basin, Colombia, in field expeditions in 2018, 2022, and 2023. We identified 17 bat flies and two species of hyperparasites, specifically M. streblida and the fungi Gloeandromyces. Our search for reports of these interactions in the Neotropics revealed that seven species of Trichobius (Streblidae) are parasitized by M. streblida, whereas Paratrichobius longicrus (Streblidae) is parasitized by Gloeandromyces pageanus f. polymorphus. These interactions have been reported in 11 countries, but our records are the first of M. streblida and Laboulbeniales fungi parasitizing bat flies in Colombia. So far, a total of 14 species of fungi and one species of mite have been associated with 19 species of bat flies, which in turn, are linked to 15 species of Neotropical bats.

Untangling an insect's virome from its endogenous viral elements.

BACKGROUND: Insects are an important reservoir of viral biodiversity, but the vast majority of viruses associated with insects have not been discovered. Recent studies have employed high-throughput RNA sequencing, which has led to rapid advances in our understanding of insect viral diversity. However, insect genomes frequently contain transcribed endogenous viral elements (EVEs) with significant homology to exogenous viruses, complicating the use of RNAseq for viral discovery. METHODS: In this study, we used a multi-pronged sequencing approach to study the virome of an important agricultural pest and prolific vector of plant pathogens, the potato aphid Macrosiphum euphorbiae. We first used rRNA-depleted RNAseq to characterize the microbes found in individual insects. We then used PCR screening to measure the frequency of two heritable viruses in a local aphid population. Lastly, we generated a quality draft genome assembly for M. euphorbiae using Illumina-corrected Nanopore sequencing to identify transcriptionally active EVEs in the host genome. RESULTS: We found reads from two insect-specific viruses (a Flavivirus and an Ambidensovirus) in our RNAseq data, as well as a parasitoid virus (Bracovirus), a plant pathogenic virus (Tombusvirus), and two phages (Acinetobacter and APSE). However, our genome assembly showed that part of the 'virome' of this insect can be attributed to EVEs in the host genome. CONCLUSION: Our work shows that EVEs have led to the misidentification of aphid viruses from RNAseq data, and we argue that this is a widespread challenge for the study of viral diversity in insects.

Why do viruses make aphids winged?

Aphids are hosts to diverse viruses and are important vectors of plant pathogens. The spread of viruses is heavily influenced by aphid movement and behaviour. Consequently, wing plasticity (where individuals can be winged or wingless depending on environmental conditions) is an important factor in the spread of aphid-associated viruses. We review several fascinating systems where aphid-vectored plant viruses interact with aphid wing plasticity, both indirectly by manipulating plant physiology and directly through molecular interactions with plasticity pathways. We also cover recent examples where aphid-specific viruses and endogenous viral elements within aphid genomes influence wing formation. We discuss why unrelated viruses with different transmission modes have convergently evolved to manipulate wing formation in aphids and whether this is advantageous for both host and virus. We argue that interactions with viruses are likely shaping the evolution of wing plasticity within and across aphid species, and we discuss the potential importance of these findings for aphid biocontrol.

Los áfidos albergan diversos virus y son vectores de importantes patógenos de plantas. La propagación de virus está fuertemente influenciada por el movimiento y el comportamiento de los áfidos. En consecuencia, la plasticidad de las alas (en la cual algunos individuos desarrollan alas dependiendo de las condiciones ambientales) es un factor importante en la propagación viral asociada a los áfidos. En este documento revisamos varios ejemplos fascinantes en los que virus de plantas transmitidos por áfidos interactúan con la plasticidad fenotípica de las alas, indirectamente manipulando la fisiología de la planta y directamente a través de interacciones moleculares con los mecanismos de plasticidad fenotípica del áfido. También describimos ejemplos recientes que demuestran como algunos virus específicos de áfidos y elementos virales endógenos localizados en los genomas de áfidos influyen en la formación de alas. Últimamente, discutimos por qué virus no relacionados con diferentes modos de transmisión han evolucionado convergentemente para manipular la formación de alas en áfidos y si este fenómeno es beneficioso para el insecto y el virus. Nosotros objetamos que las interacciones con virus están probablemente influenciando la evolución intra- e interespecífica de la plasticidad de las alas en áfidos, y discutimos el potencial de estos hallazgos para el control biológico de los áfidos.

Severe febrile neutropenia associated with satralizumab in an Argentinian neuromyelitis optica spectrum disorder patient.

BACKGROUND: Recently, satralizumab (interleukin-6 receptor blocker) was approved for seropositive neuromyelitis optica spectrum disorder (NMOSD) patients. In SAkuraSky trial, mild neutropenia was reported in 15% of patients under satralizumab. Most neutropenias were transient; grade 3-4 was not related to serious infections. So far, no severe neutropenia (<100 cell/mm3) has been reported worldwide. METHODS: We present an aquaporin-4-antibody-positive NMOSD patient who developed severe febrile neutropenia 2 weeks after adding satralizumab to her azathioprine treatment. CONCLUSION: Analytic control for satralizumab is recommended at 4 weeks. However, we recommend this control at week 2, in order to closely monitor neutrophil count and prevent further complications.

Increased let-7d-5p in non-alcoholic fatty liver promotes insulin resistance and is a potential blood biomarker for diagnosis.

BACKGROUND AND AIMS: The molecular mechanisms driving non-alcoholic fatty liver disease (NAFLD) are poorly understood; however, microRNAs might play a key role in these processes. We hypothesize that let-7d-5p could contribute to the pathophysiology of NAFLD and serve as a potential diagnostic biomarker. METHODS: We evaluated let-7d-5p levels and its targets in liver biopsies from a cross-sectional study including patients with NAFLD and healthy donors, and from a mouse model of NAFLD. Moreover, the induction of let-7d-5p expression by fatty acids was evaluated in vitro. Further, we overexpressed let-7d-5p in vitro to corroborate the results observed in vivo. Circulating let-7d-5p and its potential as a NAFLD biomarker was determined in isolated extracellular vesicles from human plasma by RT-qPCR. RESULTS: Our results demonstrate that hepatic let-7d-5p was significantly up-regulated in patients with steatosis, and this increase correlated with obesity and a decreased expression of AKT serine/threonine kinase (AKT), insulin-like growth factor 1 (IGF1), IGF-I receptor (IGF1R) and insulin receptor (INSR). These alterations were corroborated in a NAFLD mouse model. In vitro, fatty acids increased let-7d-5p expression, and its overexpression decreased AKT, IGF-IR and IR protein expression. Furthermore, let-7d-5p hindered AKT phosphorylation in vitro after insulin stimulation. Finally, circulating let-7d-5p significantly decreased in steatosis patients and receiver operating characteristic (ROC) analyses confirmed its utility as a diagnostic biomarker. CONCLUSIONS: Our results highlight the emerging role of let-7d-5p as a potential therapeutic target for NAFLD since its overexpression impairs hepatic insulin signalling, and also, as a novel non-invasive biomarker for NAFLD diagnosis.

Possible substantive improvements in the structure of the Quality of Life in Adult Cancer Survivors (QLACS) scale? A study based on its Spanish version.

PURPOSE: Quality of Life in Adult Cancer Survivors (QLACS) scale is one of the most commonly used and validated measures to assess the Health-Related Quality of Life (HRQoL) in this population. However, there are some aspects related to its structure that still deserve consideration. The aim of this study was to test the substantive improvement over the original QLACS structure resulting from several proposals reflected in the literature. METHOD: Using a cross-sectional design and Confirmatory Factorial Analysis, we explored those proposals. Reliability, convergent validity, and factor invariance across three cancer survivorships phases (re-entry, early, and long term) were also analyzed. 1.862 post-treatment survivors of diverse cancer types completed the Spanish versions of QLACS, Brief Symptom Inventory-18 (BSI-18), and Subjective Happiness Scale (SHS). RESULTS: The original model with twelve domains, grouped (with the exception of benefits) into a single total score, versus two subtotal (Generic and Cancer-specific) obtained a good fit. The values of Cronbach's alpha, Composite reliability, Average Variance Extracted indexes, and Pearson correlations supported the internal consistency and temporal stability (interval of 2-3 weeks) of the QLACS. Results also showed its adequate convergent validity and an invariant factor structure across survival periods (re-entry survivorship, early survivorship, long-term survivorship). CONCLUSION: In its original structure, albeit the replacement of the scores on the two subscales by a total score, our results support QLACS as a valid and useful tool for the assessment of HRQoL in post-treatment cancer survivors throughout the different survival phases.

Assessment of the determinants of changes and test-retest reliability in the 6-min walk test performance over a 4-month period in healthy 6-12-year-old children.

PURPOSE: The purpose of the study is to establish the determinants of change in 6-min walk test (6MWT) performance observed in children aged 6-12 years over a 4-month period, and to provide test-retest reliability (4 months) to establish the minimal detectable change (MDC). METHODS: Healthy children aged 6-12 years performed two 6MWT trials separated by a period of 4 months. Multiple linear regression analysis was performed to estimate the percentage of variance explained by the variables potentially predictive of the change in the 6MWT. We employed the intraclass correlation coefficient to assess test-retest reliability. RESULTS: Fifty-nine children (28 boys and 31 girls) were assessed. The change in distance covered during the 6MWT was significantly correlated with the growth in their height (r = 0.679; p < 0.05) and the change in their weight (r = 0.473; p < 0.05). Multiple linear regression analysis shows that the change in distance covered in the 6MWT was only explained by its growth in height (46.0% explained variance). The test-retest reliability was fair-good. After 4 months, we established a 12% change from the initial measurement (79.69 m) as the MDC for a 90% confidence level (MDC90). CONCLUSIONS: The distance covered in the 6MWT improved as the children's age, weight and height increased. The growth children's height was the most important predictor of change in distance covered in the 6MWT. An increase of at least 79.69 m (MDC90) in distance covered in the 6MWT is necessary to attribute the improvement to an intervention and not to the individual's growth.

Avian haemosporidian (Haemosporida: Plasmodium and Haemoproteus) in the department of Arauca, Colombian Orinoquia region.

Avian haemosporidian from the genera Haemoproteus and Plasmodium are a diverse and widely distributed group of vector-borne blood parasites. These parasites can have negative effects on bird survival by influencing several aspects of their life cycle, causing different clinical signs and even death. Colombia has the widest range of bird richness throughout the globe; however, the associations between haemosporidian parasites and wild birds in different ecosystems remain poorly explored. Within this frame of reference, the objective of the present study was to identify and understand haemosporidian associated with resident and migratory wild birds and their lineages in northeast Orinoquia region, Colombia. Birds were captured in 8 localities and blood samples were collected, identifying the presence of haemosporidian parasites through morphological and molecular analysis of the mitochondrial cytochrome b gene. Blood samples from 233 wild birds (86 species) were analyzed for haemosporidian parasites. Sixteen individuals (6.9%) from 15 resident and migratory species were positive for Haemoproteus or Plasmodium. Fourteen haemosporidian lineages were identified, five of them reported for the first time. These new lineages are reported in four resident birds and one boreal migratory bird (Parkesia noveboracensis). This study is the first developed in the department of Arauca and contributes to the knowledge of haemosporidian lineages and their interaction with wild birds in the Colombian Orinoquia region and South America.

Acute Alcohol Intoxication in Pediatric Emergencies.

INTRODUCTION: Alcohol intoxication in pediatrics is a growing problem in our environment. The objectives of this study are to define the prevalence of acute alcohol intoxication in the pediatric emergency department (PED) and to describe the associated symptoms and their relationship with potential risk factors. METHODS AND MATERIAL: This cross-sectional study includes patients younger than 16 years with a diagnosis of acute alcohol intoxication between March 2010 and October 2018 in the PED of a tertiary hospital. Patients with concomitant intoxication by other substances were excluded. The association between qualitative variables was determined using the χ 2 or Fisher exact test and quantitative with the Student t , Mann-Whitney U test, and simple linear regression. RESULTS: There were 136 episodes of alcohol intoxication, which represents a prevalence of 24.1/100,000 emergencies. After excluding 10 patients because of positive screening for other drugs, 126 patients with a mean age of 14.5 years (SD, 1.2 years) were included, 57.9% of whom were women. A total of 25.4% of the patients were younger than 14 years. Ethanolemia was determined in 88.9%, and its mean concentration was 195.7 mg/dL (SD, 56.5 mg/dL), with potentially serious levels (>300 mg/dL) being found in 3.6% of the patients. A relationship was found between the Glasgow Coma Scale score and ethanolemia ( B = -12.7; 95% confidence interval, -8.1 to -17.4; P < 0.001), as well as with potassium ( B = -31, 9; 95% confidence interval, -6.6 to -57.3; P = 0.014). No patient had seizures or hypoglycemia. A total of 10.3% of the patients required admission. CONCLUSIONS: Alcohol intoxication is a rare consultation reason in the PED. They usually present with mild and self-limited symptoms, being the decrease in the level of consciousness and hypokalemia the most frequent symptom and analytical alteration.

Risk Factors of Serious Bacterial Infection in Previously Healthy Children Older Than 90 Days Old With Fever and Neutropenia.

BACKGROUND: The main objective was to determine the clinical or analytical factors that independently predict risk of serious bacterial infection (RSBI) in immunocompetent patients older than 90 days given a diagnosis of fever and for whom neutropenia was an incidental finding. The secondary objective was to describe the prevalence of serious bacterial infections (SBIs). METHODS: This is a 3-year-long, multicenter, prospective analytical and observational study carried out at 6 pediatric emergency departments. Data for epidemiological, clinical, and analytical variables were collected. RESULTS: One hundred forty patients with febrile neutropenia (60.7% mild, 39.3% moderate to severe) were recruited. Serious bacterial infection incidence was 15.0% (95% confidence interval [CI], 9-21): 1 Invasive Bacterial Infection (Staphylococcus epidermidis bacteremia), 10 urinary tract infections, 8 pneumonias, and 2 cellulitis. Median total neutrophil counts per microliter showed no statistically significant differences (P = 0.512; 1000 [750-1200] in SBI patients vs 1100 [800-1300] in non-SBI patients). Higher RSBI was observed in patients with neutrophils less than 20% relative to total leukocytes (SBI, 15, 26.3%) than in those with neutrophils of 20% or greater (SBI, 6, 7.2%) (odds ratio, 4.6; 95% CI, 1.7-12.7). In patients with greater than 5000 leukocytes/µL, a percentage of neutrophils less than 20% was related to a greater RSBI with a trend toward statistical significance (odds ratio, 6.1; 95% CI, 0.7-51.1; P = 0.066). The clinical variables did not show a significant association with RSBI. CONCLUSIONS: None of the clinical or analytical variables assessed were associated with the RSBI. However, according to a post hoc analysis, in patients with greater than 5000 leukocytes/µL, a neutrophil percentage less than 20% could be an independent risk factor for SBI. A thorough physical examination and basic diagnostic tests (urinalysis and chest x-ray) may help to establish a diagnosis of SBI in the vast majority of cases.

Implication of miR-155-5p and miR-143-3p in the Vascular Insulin Resistance and Instability of Human and Experimental Atherosclerotic Plaque.

(1) Background: Cardiovascular diseases (CVDs) are the main cause of death in developed countries, being atherosclerosis, a recurring process underlying their apparition. MicroRNAs (miRNAs) modulate the expression of their targets and have emerged as key players in CVDs; (2) Methods: 18 miRNAs were selected (Pubmed and GEO database) for their possible role in promoting atherosclerosis and were analysed by RT-qPCR in the aorta from apolipoprotein E-deficient (ApoE-/-) mice. Afterwards, the altered miRNAs in the aorta from 18 weeks-ApoE-/- mice were studied in human aortic and carotid samples; (3) Results: miR-155-5p was overexpressed and miR-143-3p was downregulated in mouse and human atherosclerotic lesions. In addition, a significant decrease in protein kinase B (AKT), target of miR-155-5p, and an increase in insulin-like growth factor type II receptor (IGF-IIR), target of miR-143-3p, were noted in aortic roots from ApoE-/- mice and in carotid plaques from patients with advanced carotid atherosclerosis (ACA). Finally, the overexpression of miR-155-5p reduced AKT levels and its phosphorylation in vascular smooth muscle cells, while miR-143-3p overexpression decreased IGF-IIR reducing apoptosis in vascular cells; (4) Conclusions: Our results suggest that miR-155-5p and miR-143-3p may be implicated in insulin resistance and plaque instability by the modulation of their targets AKT and IGF-IIR, contributing to the progression of atherosclerosis.

Bacteria related to tick-borne pathogen assemblages in Ornithodoros cf. hasei (Acari: Argasidae) and blood of the wild mammal hosts in the Orinoquia region, Colombia.

Interest in research on soft ticks has increased in recent decades, leading to valuable insight into their role as disease vectors. The use of metagenomics-based analyses have helped to elucidate ecological factors involved in pathogen, vector, and host dynamics. To understand the main bacterial assemblages present in Ornithodoros cf. hasei and its mammalian hosts, 84 ticks and 13 blood samples from bat hosts (Chiroptera) were selected, and the 16S rRNA gene V4 region was sequenced in five pools (each one related to each host-tick pairing). Bacterial taxonomic assignment analyses were performed by comparing operational taxonomic units (OTUs) shared between ticks and their host blood. This analysis showed the presence of Proteobacteria (38.8%), Enterobacteriaceae (25%), Firmicutes (12.3%), and Actinobacteria (10.9%) within blood samples, and Rickettsiaceae (39%), Firmicutes (25%), Actinobacteria (13.1%), and Proteobacteria (9%) within ticks. Species related to potentially pathogenic genera were detected in ticks, such as Borrelia sp., Bartonella tamiae, Ehrlichia sp. and Rickettsia-like endosymbiont, and the presence of these organisms was found in all analyzed bat species (Cynomops planirostris, Molossus pretiosus, Noctilio albiventris), and O. cf. hasei. About 41-48.6% of bacterial OTUs (genera and species) were shared between ticks and the blood of bat hosts. Targeted metagenomic screening techniques allowed the detection of tick-associated pathogens for O. cf. hasei and small mammals for the first time, enabling future research on many of these pathogens.

Discriminating Bacterial Infection from Other Causes of Fever Using Body Temperature Entropy Analysis.

Body temperature is usually employed in clinical practice by strict binary thresholding, aiming to classify patients as having fever or not. In the last years, other approaches based on the continuous analysis of body temperature time series have emerged. These are not only based on absolute thresholds but also on patterns and temporal dynamics of these time series, thus providing promising tools for early diagnosis. The present study applies three time series entropy calculation methods (Slope Entropy, Approximate Entropy, and Sample Entropy) to body temperature records of patients with bacterial infections and other causes of fever in search of possible differences that could be exploited for automatic classification. In the comparative analysis, Slope Entropy proved to be a stable and robust method that could bring higher sensitivity to the realm of entropy tools applied in this context of clinical thermometry. This method was able to find statistically significant differences between the two classes analyzed in all experiments, with sensitivity and specificity above 70% in most cases.

High-Throughput Fluorescence-Based Screen Identifies the Neuronal MicroRNA miR-124 as a Positive Regulator of Alphavirus Infection.

MicroRNAs (miRNAs) are small regulatory RNAs which act by modulating the expression of target genes. In addition to their role in maintaining essential physiological functions in the cell, miRNAs can also regulate viral infections. They can do so directly by targeting RNAs of viral origin or indirectly by targeting host mRNAs, and this can result in a positive or negative outcome for the virus. Here, we performed a fluorescence-based miRNA genome-wide screen in order to identify cellular miRNAs involved in the regulation of arbovirus infection in human cells. We identified 16 miRNAs showing a positive effect on Sindbis virus (SINV) expressing green fluorescent protein (GFP), among which were a number of neuron-specific ones such as miR-124. We confirmed that overexpression of miR-124 increases both SINV structural protein translation and viral production and that this effect is mediated by its seed sequence. We further demonstrated that the SINV genome possesses a binding site for miR-124. Both inhibition of miR-124 and silent mutations to disrupt this binding site in the viral RNA abolished positive regulation. We also proved that miR-124 inhibition reduces SINV infection in human differentiated neuronal cells. Finally, we showed that the proviral effect of miR-124 is conserved in other alphaviruses, as its inhibition reduces chikungunya virus (CHIKV) production in human cells. Altogether, our work expands the panel of positive regulation of the viral cycle by direct binding of host miRNAs to the viral RNA and provides new insights into the role of cellular miRNAs as regulators of alphavirus infection.IMPORTANCE Arthropod-borne (arbo) viruses are part of a class of pathogens that are transmitted to their final hosts by insects. Because of climate change, the habitat of some of these insects, such as mosquitoes, is shifting, thereby facilitating the emergence of viral epidemics. Among the pathologies associated with arbovirus infection, neurological diseases such as meningitis and encephalitis represent a significant health burden. Using a genome-wide miRNA screen, we identified neuronal miR-124 as a positive regulator of the Sindbis and chikungunya alphaviruses. We also showed that this effect was in part direct, thereby opening novel avenues to treat alphavirus infections.

A genomic island in Brucella involved in the adhesion to host cells: Identification of a new adhesin and a translocation factor.

Adhesion to host cells is the first step in the virulence cycle of any pathogen. In Gram-negative bacteria, adhesion is mediated, among other virulence factors such as the lipopolysaccharides, by specific outer-membrane proteins generally termed adhesins that belong to a wide variety of families and have different evolutionary origins. In Brucella, a widespread zoonotic pathogen of animal and human health concern, adhesion is central as it may determine the intracellular fate of the bacterium, an essential stage in its pathogenesis. In the present paper, we further characterised a genomic locus that we have previously reported encodes an adhesin (BigA) with a bacterial immunoglobulin-like domain (BIg-like). We found that this region encodes a second adhesin, which we have named BigB; and PalA, a periplasmic protein necessary for the proper display in the outer membrane of BigA and BigB. Deletion of bigB or palA diminishes the adhesion of the bacterium and overexpression of BigB dramatically increases it. Incubation of cells with the recombinant BIg-like domain of BigB induced important cytoskeletal rearrangements and affected the focal adhesion sites indicating that the adhesin targets cell-cell or cell-matrix proteins. We additionally show that PalA has a periplasmic localisation and is completely necessary for the proper display of BigA and BigB, probably avoiding their aggregation and facilitating their transport to the outer membrane. Our results indicate that this genomic island is entirely devoted to the adhesion of Brucella to host cells.

How Far Can Life Cycle Assessment Be Simplified? A Protocol to Generate Simple and Accurate Models for the Assessment of Energy Systems and Its Application to Heat Production from Enhanced Geothermal Systems.

Life cycle assessments (LCAs) quantify environmental impacts of systems and support decision-making processes. LCAs are however time-consuming and difficult to conduct for nonexperts, thus calling for simplified approaches for multicriteria environmental assessments. In this paper, a five-step protocol is presented to generate simplified arithmetic equations from a reference parametrized LCA model of an energy system and its application illustrated for an enhanced geothermal system for heat generation with very low direct emissions in continental Europe. The simplified models estimate seven environmental impacts (climate change, freshwater ecotoxicity, human health, minerals and metals, and fossil resources depletion, and acidification) based on six technological parameters: number of injection and production wells, power of the production and injection pump, average well length, thermal power output, and eight background parameters defining the European electricity mix. A global sensitivity analysis identified these parameters as influencing the variance of the environmental impacts the most. Ensuring the representativeness of the reference LCA model and the validity of the simplified models requires thorough assessment. This protocol allows to develop relevant alternatives to detailed LCAs for quick and multicriteria environmental impact assessments of energy systems, showing that LCAs can be simplified to system-specific equations based on few, easily quantified, parameters.

Ticks (Acari: Ixodoidea) associated with mammals in Colombia: a historical review, molecular species confirmation, and establishment of new relationships.

Ticks are considered the second most important vectors of pathogens worldwide, after mosquitoes. This study provides a systematic review of vector-host relationships between ticks and mammals (domestic and wild) and consolidates information from studies conducted in Colombia between 1911 and 2020. Using the PRISMA method, 71 scientific articles containing records for 51 tick species (Argasidae and Ixodidae) associated with mammals are reported. The existing information on tick-mammal associations in Colombia is scarce, fragmented, or very old. Moreover, 213 specimens were assessed based on morphological and molecular analyses, which allowed confirming eight tick species associated with mammals: Amblyomma calcaratum, Amblyomma dissimile, Amblyomma mixtum, Amblyomma nodosum, Amblyomma ovale, Amblyomma varium, Ixodes luciae, and Ixodes tropicalis. Several tick species are molecularly confirmed for Colombia and nine new relationships between ticks and mammals are reported. This research compiles and confirms important records of tick-mammal associations in Colombia.