Dwarf shrub facilitates seedling recruitment and plant diversity in semiarid grasslands

The facilitation mechanism maintains ecosystem richness by increasing seedling recruitment. Overgrazed grasslands of northwestern Patagonia are invaded by shrubs that could promote the seedling recruitment of forage species. We investigated the role of Acaena splendens shrubs on the maintenance of diversity and its usefulness as a nurse shrub in the recruitment of Festuca pallescens, a grass of high forage value present with a low cover in degraded grasslands. To test the performance of A.splendens as a nurse plant in non-degraded grassland, we recorded the species richness four years inside of A. splendens senescent shrubs and in gaps among dominant tussock grasses. Species were grouped in four functional groups: annual and biannual herbs and grasses, perennial herbs, perennial grasses and shrubs. To test the usefulness of A. splendens in the restoration of degraded grassland, we monitored the seedling emergence and survival of F. pallescens inside A. splendens and in gaps. We related seedling survival to meteorological and microenviron-mental conditions. Species richness was higher in Acaena nurse plants than in gaps. The frequency of functional groups, with exception of annual and biannual herbs and grasses, were higher in Acaena than in gaps. Seedling emergence and survival of F. pallescens were higher in Acaena, but the seedlings died in summer in both microsites. Mean maximum temperature was higher and mean minimum humidity lower in gaps than in Acaena during spring. However, the spring-summer season in which we monitored F. pallescens survival, was exceptionally dry and hot, affecting the survival of F. pallescens seedlings. Our results show that A. splendens act as a nurse species increasing the richness in the non-degraded grassland and facilitating the seedling recruitment of an important forage species in the degraded grassland. Nevertheless, the facilitation mechanism will fail in drought conditions, indicating that this restoration tool is limited by climate.Fil: Gonzalez, Sofia Laura. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche. Laboratorio de Ecotono; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Ghermandi, Luciana. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche. Laboratorio de Ecotono; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentin

Alien plant species on roadsides of the northwestern Patagonian steppe (Argentina)

The introduction of alien species represents one of the greatest threats to biodiversity worldwide. Highway construction increases the dispersal and invasion of exotic plant species. This study examined the assembly process of the plant communities to determine whether the roadsides of the Patagonian steppe represent a reservoir and dispersal source of invasive exotic species. We analyzed the composition of exotic and native species and functional groups present in the established vegetation and seed banks of roadsides and reference areas nearby. The type of dispersal of exotic and native species at the roadsides was also evaluated. Total cover and that of exotic and native species was lower at the roadsides than in the reference areas; however, at the roadsides the cover and seed abundance of exotic species was higher than that of native species. In the roadsides vegetation, native shrubs such as Acaena splendens predominated, along with exotic perennial herbs and grasses which were mainly represented by Rumex acetosella. In the seed bank the predominant species were exotic perennial herbs, also represented by R. acetosella, annual exotic species such as Epilobium brachycarpum and Verbascum thapsus, and annual native species such as Heliotropium paronychioides. No exotic shrubs were found either at the roadsides or in the reference areas. The species at the roadsides did not present a dominant type of dispersal. The abundance of exotic species at the roadsides, both in the aboveground vegetation and the seed bank, may be due to the stressful environment and the characteristics of the species themselves, such as the ability to form seed banks. This work revealed that the roadsides of the Patagonian steppe constitute reservoirs of invasive exotic species, highlighting the importance of identifying them and controlling their spread, with a view to generating ecosystem management programs.Fil: Chichizola, Giselle. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Patagonia Norte. Instituto de Investigaciones En Biodiversidad y Medioambiente. Subsede San Martín de Los Andes-inibioma | Universidad Nacional del Comahue. Centro Regional Universitario Bariloche. Instituto de Investigaciones En Biodiversidad y Medioambiente. Subsede San Martín de Los Andes-inibioma.; ArgentinaFil: Gonzalez, Sofia Laura. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Patagonia Norte. Instituto de Investigaciones En Biodiversidad y Medioambiente. Subsede San Martín de Los Andes-inibioma | Universidad Nacional del Comahue. Centro Regional Universitario Bariloche. Instituto de Investigaciones En Biodiversidad y Medioambiente. Subsede San Martín de Los Andes-inibioma.; ArgentinaFil: Rovere, Adriana. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Patagonia Norte. Instituto de Investigaciones En Biodiversidad y Medioambiente. Subsede San Martín de Los Andes-inibioma | Universidad Nacional del Comahue. Centro Regional Universitario Bariloche. Instituto de Investigaciones En Biodiversidad y Medioambiente. Subsede San Martín de Los Andes-inibioma.; Argentin

Mapping the wildland-urban interface from houses locations and terrain slope in Patagonia Argentina

Urbanization of forested areas increases the surface of wildland-urban interface (WUI), where fire is the primary hazard for humans and ecosystems. We determined the WUI using a novel approach in NW Patagonia, Argentina and evaluated its relationship with the fire ignition points. The WUI expands a greater distance on upslopes, where the rate of fire spread is highest. The WUI reaches the maximum distance under the most hazardous conditions: houses surrounded by fuels with steep slopes towards them. In the Bariloche district in 2021, the WUI included 81% of the houses and occupied 37% (11,006 ha) of the total study area. Between 2015 and 2021, 77% of fire ignitions occurred in the WUI, highlighting the relevance of urban growth planification and the management of fuel load to reduce wildfire riskFil: Sanucci, Corina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Gonzalez, Sofia Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Ghermandi, Luciana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentin

Germinación de Oenothera odorata, onagráceae ruderal endémica de Argentina

Onagraceae es una familia bien definida de plantas con flores y muy utilizada por el hombre. En Argentina posee numerosas representantes indígenas, distribuidas en 8 géneros y 75 especies, sien-do el 19% de las especies endémicas. Muchas onagráceas son ruderales y facilitan el establecimiento de especies más tardías, siendo útiles para la restauración de áreas degradadas. Dada la importancia de conocer las características de las semillas y de la germinación para su utilización en proyectos de restauración, se indagó sobre aspectos fisiológicos básicos de la germinación de Oenotheraodorata Jacq., hierba ruderal endémica de Argentina. El material se colectó de taludes y bordes de la Ruta Na-cional 40, dentro del éjido municipal de San Carlos de Bariloche, en la Provincia Fitogeográfica Patagónica. La construcción de rutas genera áreas degradadas denudadas de vegetación, donde la especie O. odorata podría utilizarse para iniciar los trabajos de revegetación y consolidar el sustrato. Se evaluó el porcentaje de germinación (G), el tiempo medio de germinación (MGT) y el tiempo hasta el inicio de la germinación (TUG) de un control (C) y de tratamientos pre-germinativos: estra-tificación húmeda fría de 45 días (CMS), escarificación mecánica con bisturí (MS). Los porcentajes de germinación fueron elevados (98% CMS, 96% MS, 93% C), solo se registraron diferencias entre CMS y C. El MGT fue menor en el tratamiento de CMS, respecto al C, pero fue similar al de MS. El TUG fue de 4 días para todos los tratamientos. En conclusión, la especie carece de mecanismos de dormición bajo las condiciones experimentales, lo que sumado al hecho de crecer en ambientes disturbados, ser endémica, y capturar metales pesados, la convierte en una especie propicia para utilizarse en trabajos de restau-ración ecológica en áreas afectadas por el transporte.The Onagraceae are a well-defined family of flowering plants much used by man. Many representatives of this group, which contains 75 species belonging to 8 genera, are indigenous to Argentina, and 19% of these are commonly found throughout the country. Many Onagraceae are ruderal and promote the subsequent establishment of other species, thus contributing to the restoration of degraded areas. Since it is important to know the characteristics of seeds to be used in restoration projects, we studied the basic germination physiology of Oenothera odorata Jacq., a ruderal plant indigenous to Argentina. Material was collected from roadsides and embankments along National highway 40 in the municipality of San Carlos de Bariloche, which lies within the Patagonian phytogeographic province. Road construction generates degraded areas where O. odorata could be used to initiate revegetation and consolidate the substrate. We evaluated percentage germination (G), mean germination time (MGT) and time till initiation of germination (TUG) of a control (C) and of the following pre-germination treatments: 45 days cold moist stratification (CMS) and mechanical scarification with a scalpel (MS). Germination percentages were high (98% CMS, 96% MS, 93% C), with differences recorded only between CMS and C. MGT was lower in the CMS treatment than the control, but similar to MS. TUG was 4 days for all treatments. In conclusion, this species lacks dormancy mechanisms under these experimental conditions, which, together with the fact that it grows in disturbed sites, is endemic, and captures heavy metals, makes it suitable for use in the ecological restoration of areas affected by transport systems.Fil: Chichizola, Giselle. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Rovere, Adriana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Gonzalez, Sofia Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentin

Fire hazard assessment at different scales in the wildland-urban interface of semiarid areas of northern Patagonia

Wildland-urban interface (WUI) fires have increased in the last decades, putting lives and homes at risk, and fire hazard assessment is a useful tool to develop plans for prevention and fire management. In northwestern Patagonia, the WUI areas are principally located around the urbanized zones that are not only cities or towns but settlements surrounded by the natural environment. In Patagonia, there are the largest and most ancient national parks of Argentina with areas where former settlers develop their livestock activities. We assessed the fire hazard in the Laguna Blanca National Park (LBNP) located in Neuquén province (Patagonia, Argentina) dominated by steppe vegetation. We performed the study at two scales: community and species. Community scale comprised the variables vegetation cover, slope, and rock fragments, whereas species scale included flammability variables of dominant species (tussock grasses and shrubs) at leaf- and plant-level. We integrated all variables at different scales and grouped the vegetation units into three classes using multivariate analysis. Finally, we established three fire hazard categories for each vegetation unit: low, moderate, and high, to elaborate a fire hazard map. Three vegetation units, which represented 37% of the area of the park, were categorized with high fire hazard because of the high cover and horizontal continuity of dominant vegetation. The tussock grass Pappostipa speciosa and the shrubs Mulinum spinosum, Nassauvia axillaris, and Anarthorphyllum rigidum were the most flammable species and the most frequent species in the park. Land uses in the park (i.e., transhumance and tourism) would be regulated with the collaboration of settlers because increase the vulnerability to wildfires. Our fire hazard map constitutes a valuable tool because it identified the most vulnerable WUI in the LBNP. This study emphasizes the need to include flammability and fuel load studies in fire management plans to better protect human lives and natural resources in protected areas.Fil: Gonzalez, Sofia Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Arias Aller, Soledad. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Ghermandi, Luciana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentin

Seed germination of Phacelia secunda (Boraginaceae) and Eryngium paniculatum (Apiaceae), perennial herbs from Patagonia Argentine

El objetivo fue evaluar los requerimientos de germinación de Phacelia secunda J.F. Gmel. y Eryngium paniculatum Cav. y Dombey ex F. Delaroche, herbáceas perennes colonizadoras de ambientes degradados del noroeste patagónico argentino y de interés para la restauración ecológica. Se evaluó el porcentaje, tiempo medio e inicio de germinación en un control (C) y dos tratamientos pre-germinativos: escarificación mecánica con bisturí (EM) y estratificación húmeda fría durante 45 días (EHF). En P. secunda, el porcentaje de germinación en el tratamiento EHF (2%) fue menor que en el C (24%) y el tratamiento EM (16%). En E. paniculatum se encontraron diferencias entre el C (94%) y el tratamiento EHF (82%), pero no entre el C y EM (91%). El tratamiento EHF aceleró el inicio de la geminación en ambas especies. Las semillas de P. secunda mostraron baja capacidad de germinación siendo necesario evaluar nuevos tratamientos. Eryngium paniculatum mostró alta capacidad germinativa aún en el control, lo que evidencia que no requiere tratamientos pregerminativos específicos.The aim was to evaluate the seed germination requirements of Phacelia secunda J.F. Gmel. and Eryngium paniculatum Cav. y Dombey ex F. Delaroche, perennial herbaceous colonizers of degraded environments of northwest Argentinian Patagonia and of interest for ecological restoration. The germination percentage, mean germination time and time until initiation of germination of a control (C) and two pre-germination treatments: Mechanical scarification with a scalpel (EM) and 45 days cold moist stratification (EHF) were evaluated. In P. secunda, the germination percentage in EHF treatment (2%) was lower than in C (24%) and EM (16%) treatment. In E. paniculatum, differences between C (94%) and EHF (82%) were found, but not between C and EM (91%). EHF treatment accelerated the germination initiation in both species. Seeds of P. secunda showed low germination capacity being necessary to evaluate new treatments. Eryngium paniculatum showed high germination capacity in the control. Thus this species does not require specific pre-germination treatments.Fil: Chichizola, Giselle. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Rovere, Adriana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Gonzalez, Sofia Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentin

Islet-1 specifies the identity of hypothalamic melanocortin neurons and is critical for normal food intake and adiposity in adulthood

Food intake and body weight regulation depend on proper expression of the proopiomelanocortin gene (Pomc) in a group of neurons located in the mediobasal hypothalamus of all vertebrates. These neurons release POMC-encoded melanocortins, which are potent anorexigenic neuropeptides, and their absence from mice or humans leads to hyperphagia and severe obesity. Although the pathophysiology of hypothalamic POMC neurons is well understood, the genetic program that establishes the neuronal melanocortinergic phenotype and maintains a fully functional neuronal POMC phenotype throughout adulthood remains unknown. Here, we report that the early expression of the LIM-homeodomain transcription factor Islet 1 (ISL1) in the developing hypothalamus promotes the terminal differentiation of melanocortinergic neurons and is essential for hypothalamic Pomc expression since its initial onset and throughout the entire lifetime. We detected ISL1 in the prospective hypothalamus just before the onset of Pomc expression and, from then on, Pomc and Isl1 coexpress. ISL1 binds in vitro and in vivo to critical homeodomain binding DNA motifs present in the neuronal Pomc enhancers nPE1 and nPE2, and mutations of these sites completely disrupt the ability of these enhancers to drive reporter gene expression to hypothalamic POMC neurons in transgenic mice and zebrafish. ISL1 is necessary for hypothalamic Pomc expression during mouse and zebrafish embryogenesis. Furthermore, conditional Isl1 inactivation from POMC neurons impairs Pomc expression, leading to hyperphagia and obesity. Our results demonstrate that ISL1 specifies the identity of hypothalamic melanocortin neurons and is required for melanocortin-induced satiety and normal adiposity throughout the entire lifespanFil: Nasif, Sofia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular; ArgentinaFil: Silva Junqueira de Souza, Flavio. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Gonzalez, Laura Elisabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular; ArgentinaFil: Yamashita, Miho. University of Michigan. Department of Molecular and Integrative Physiology; Estados UnidosFil: Orquera, Daniela Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular; ArgentinaFil: Low, Malcolm J.. University of Michigan. Department of Molecular and Integrative Physiology; Estados UnidosFil: Rubinstein, Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. University of Michigan. Department of Molecular and Integrative Physiology; Estados Unido

SOX2 Expression and Transcriptional Activity Identifies a Subpopulation of Cancer Stem Cells in Sarcoma with Prognostic Implications

Stemness in sarcomas is coordinated by the expression of pluripotency factors, like SOX2, in cancer stem cells (CSC). The role of SOX2 in tumor initiation and progression has been well characterized in osteosarcoma. However, the pro-tumorigenic features of SOX2 have been scarcely investigated in other sarcoma subtypes. Here, we show that SOX2 depletion dramatically reduced the ability of undifferentiated pleomorphic sarcoma (UPS) cells to form tumorspheres and to initiate tumor growth. Conversely, SOX2 overexpression resulted in increased in vivo tumorigenicity. Moreover, using a reporter system (SORE6) which allows to monitor viable cells expressing SOX2 and/or OCT4, we found that SORE6+ cells were significantly more tumorigenic than the SORE6- subpopulation. In agreement with this findings, SOX2 expression in sarcoma patients was associated to tumor grade, differentiation, invasive potential and lower patient survival. Finally, we studied the effect of a panel of anti-tumor drugs on the SORE6+ cells of the UPS model and patient-derived chondrosarcoma lines. We found that the mithramycin analogue EC-8042 was the most efficient in reducing SORE6+ cells in vitro and in vivo. Overall, this study demonstrates that SOX2 is a pro-tumorigenic factor with prognostic potential in sarcoma. Moreover, SORE6 transcriptional activity is a bona fide CSC marker in sarcoma and constitutes an excellent biomarker for evaluating the efficacy of anti-tumor treatments on CSC subpopulations.This work was supported by the Agencia Estatal de Investigación (AEI) [MINECO/Fondo Europeo de Desarrollo Regional (FEDER) (SAF-2016-75286-R to R.R.), ISC III/FEDER (Miguel Servet Program CPII16/00049 to R.R., Sara Borrell Program CD16/00103 to S.T.M. and PI16/00280 and PI19/00560 to J.M.G-P) and Consorcio CIBERONC CB16/12/00390)] and the Plan de Ciencia Tecnología e Innovación del Principado de Asturias/FEDER (IDI/2018/155) to J.P.R and Predoctoral Fellowship Severo Ochoa (BP-17-108) to O.E.S

Prevalence of Intestinal Coccidia: First Description of Cyclosporidiosis Associated with Diarrhea in Children in Colombia

Background: In Colombia, the studies about the etiology of acute diarrhea disease (ADD) in children by using standard stool culture techniques methods and DNA detection tools for intestinal virus show that viral origin was the most frequent, however still between 16 to 45% of the cases of unknown etiology. Specific staining techniques or high sensitivity molecular methods for the intestinal coccidia Cryptosporidium sp and Cyclospora sp have been not applied in the Colombian studies, for this reason, the current situation of these intestinal coccidia in Colombia as cause of diarrhea is unknown.  Objective: To estimate the frequency of Cryptosporidium sp. and Cyclospora sp. and to analyze the association between infection and clinical manifestations on children with acute diarrhea consulting the pediatrics emergency service of a third level Hospital. Methods:  An observational descriptive study was performed in 150 children that consulted the emergency service at the Hospital San Juan de Dios in Armenia, Colombia, in the period between April 1st and May 31st of 2022. We applied questionnaires and collected primary data from clinical records of children, as well as stool samples of each child after receiving informed consent from the parents and/or legal guardian of the minors. To identify the pathogenic intestinal coccidia (Cryptosporidium sp. and Cyclospora sp.), we used stool fresh preparations with 1% iodine and stained by a modified Ziehl Nielsen coloration protocol (Kinyoun stain). Samples were examined by expert microbiologists on a light microscope with a 40x objective. Prevalence and odds ratios were estimated. For statistical analysis differences in proportions among groups were compared via the X2 test and Fisher exact test. For non-parametric data, differences of means between two groups were analyzed through a Kruskall-Wallis test. Differences of medians were analyzed via Kruskal-Wallis test for non-parametric variables and analysis of variance (ANOVA) for parametric variables; statistical significance was considered when p ≤ 0.05. Statistical calculations were made by using software factors in Epi Info 7.2 Epi-Info version 3.5.1 (CDC, Atlanta).  Results: The prevalence of infection in the children that went to the urgency service was of 19,7% by Cryptosporidium sp. and 10,9% by Cyclospora sp. The 59,2% of children with cryptosporidiosis and 66,6% of children with cyclosporidiosis were hospitalized. There was a statistically significant association between the presence of parasite in stools and fever in cyclosporidiosis (93,3% of children with cyclosporidiosis vs. 56% by other causes, OR 10,7 IC95% 1,3-84; p= 0,004).  Conclusions: The study results indicate the need to use specific diagnostic techniques to identify Cryptosporidium sp and Cyclospora sp in children with diarrhea, because they are frequent and are treatable with specific antiparasitic medication. We recommend that its search should be done systematically

Plasma miRNA profile at COVID-19 onset predicts severity status and mortality

BACKGROUND: MicroRNAs (miRNAs) have a crucial role in regulating immune response against infectious diseases, showing changes early in disease onset and before the detection of the pathogen. Thus, we aimed to analyze the plasma miRNA profile at COVID-19 onset to identify miRNAs as early prognostic biomarkers of severity and survival. METHODS AND RESULTS: Plasma miRNome of 96 COVID-19 patients that developed asymptomatic/mild, moderate and severe disease was sequenced together with a group of healthy controls. Plasma immune-related biomarkers were also assessed. COVID-19 patients showed 200 significant differentially expressed (SDE) miRNAs concerning healthy controls, with upregulated putative targets of SARS-CoV-2, and inflammatory miRNAs. Among COVID-19 patients, 75 SDE miRNAs were observed in asymptomatic/mild compared to symptomatic patients, which were involved in platelet aggregation and cytokine pathways, among others. Moreover, 137 SDE miRNAs were identified between severe and moderate patients, where miRNAs targeting the SARS CoV-2 genome were the most strongly disrupted. Finally, we constructed a mortality predictive risk score (miRNA-MRS) with ten miRNAs. Patients with higher values had a higher risk of 90-days mortality (hazard ratio = 4.60; p-value < 0.001). Besides, the discriminant power of miRNA-MRS was significantly higher than the observed for age and gender (AUROC = 0.970 vs. 0.881; p = 0.042). CONCLUSIONS: SARS-CoV-2 infection deeply disturbs the plasma miRNome from an early stage of COVID-19, making miRNAs highly valuable as early predictors of severity and mortality