85 research outputs found
Supercolonial structure of invasive populations of the tawny crazy ant Nylanderia fulva in the US
Background: Social insects are among the most serious invasive pests in the world, particularly successful at monopolizing environmental resources to outcompete native species and achieve ecological dominance. The invasive success of some social insects is enhanced by their unicolonial structure, under which the presence of numerous queens and the lack of aggression against non-nestmates allow high worker densities, colony growth, and survival while eliminating intra-specific competition. In this study, we investigated the population genetics, colony structure and levels of aggression in the tawny crazy ant, Nylanderia fulva, which was recently introduced into the United States from South America. Results: We found that this species experienced a genetic bottleneck during its invasion lowering its genetic diversity by 60%. Our results show that the introduction of N. fulva is associated with a shift in colony structure. This species exhibits a multicolonial organization in its native range, with colonies clearly separated from one another, whereas it displays a unicolonial system with no clear boundaries among nests in its invasive range. We uncovered an absence of genetic differentiation among populations across the entire invasive range, and a lack of aggressive behaviors towards conspecifics from different nests, even ones separated by several hundreds of kilometers. Conclusions: Overall, these results suggest that across its entire invasive range in the U.S.A., this species forms a single supercolony spreading more than 2000 km. In each invasive nest, we found several, up to hundreds, of reproductive queens, each being mated with a single male. The many reproductive queens per nests, together with the free movement of individuals between nests, leads to a relatedness coefficient among nestmate workers close to zero in introduced populations, calling into question the stability of this unicolonial system in which indirect fitness benefits to workers is apparently absent.Fil: Eyer, Pierre André. Texas A&M University; Estados UnidosFil: McDowell, Bryant. Texas A&M University; Estados UnidosFil: Johnson, Laura N. L.. Texas A&M University; Estados UnidosFil: Calcaterra, Luis Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Fundación para el Estudio de Especies Invasivas; ArgentinaFil: Fernández, María Belén. Fundación para el Estudio de Especies Invasivas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Shoemaker, Dewayne. University of Tennessee; Estados UnidosFil: Puckett, Robert T.. Texas A&M University; Estados UnidosFil: Vargo, Edward L.. Texas A&M University; Estados Unido
Susceptibility mapping of shallow landslides inducing debris flows: a comparison of physics-based approaches
The assessment of timing and potential locations of rainfallinduced shallow landslides through mathematical models represents a challenge for the assessment of landslide hazard, especially in cases with limited or not available data. In fact, modeling slope hydrological response and stability requires accurate estimates of unsaturated/saturated hydraulic and geotechnical properties of materials involved in landsliding, as well as climate and topography. Such aspect is relevant for the prediction of location and timing of landslide events, which is greatly needed to reduce their catastrophic effects in terms of economic losses and casualties. To such a scope, we present the comparison of results of two physics-based models applied to the assessment of susceptibility to shallow rainfall-induced landslides in Valtellina region (northern Italy). The analyses were carried out considering effects of availability, resolution and type of data concerning spatial distribution, thickness and properties of soils coverings. For such a scope, the Transient Rainfall Infiltration and Grid-Based Regional Slope-Stability (TRIGRS) and the Climatic Rainfall Hydrogeological Modeling Experiment (CHRyME) models were considered. The study emphasizes issues in performing distributed numerical slope stability modeling depending on the availability of spatially distributed soil properties which hamper the quality of physic-based models. Further analyses aimed at the probabilistic assessment of landslide spatial distribution, related to a specific value of rainfall threshold, can be considered as potentially applicable to multi-scale landslide hazard mapping and extendable to other similar mountainous frameworks
Conservation of Zebrafish MicroRNA-145 and Its Role during Neural Crest Cell Development
The neural crest is a multipotent cell population that develops from the dorsal neural fold of vertebrate embryos in order to migrate extensively and differentiate into a variety of tissues. A number of gene regulatory networks coordinating neural crest cell specification and differentiation have been extensively studied to date. Although several publications suggest a common role for microRNA-145 (miR-145) in molecular reprogramming for cell cycle regulation and/or cellular differentiation, little is known about its role during in vivo cranial neural crest development. By modifying miR-145 levels in zebrafish embryos, abnormal craniofacial development and aberrant pigmentation phenotypes were detected. By whole-mount in situ hybridization, changes in expression patterns of col2a1a and Sry-related HMG box (Sox) transcription factors sox9a and sox9b were observed in overexpressed miR-145 embryos. In agreement, zebrafish sox9b expression was downregulated by miR-145 overexpression. In silico and in vivo analysis of the sox9b 3′UTR revealed a conserved potential miR-145 binding site likely involved in its post-transcriptional regulation. Based on these findings, we speculate that miR-145 participates in the gene regulatory network governing zebrafish chondrocyte differentiation by controlling sox9b expressionThis research was funded by a CONICET External Grant (March 2018 to A.M.J.W.), an ANPCyT PICT Grant (PICT-2017-0509 to A.M.J.W.), and a CONICET PIP Grant (PIP-2015-0719 to N.B.C.)S
Evaluation of the applicability of sediment transport models to dam filling prediction in different Italian geological contexts
Artificial reservoirs are crucial infrastructures, since they allow for the management of the water resource they store and for their role in the hydroelectric production. Water is modulated and stored inside artificial basins built upstream of the dams for hydroelectric, industrial, drinking, irrigation, and flood mitigation purposes. However, as time passes, the deposition of solid material, transported by rivers flowing into the reservoir, reduces its storage capacity. In this work, a novel physicallybased erosion and sediment transport model developed by Politecnico di Milano (SMART-SED) is used to estimate dam filling in different Italian geological contexts. The present model differs from others in the literature since it can automatically detect drainage zones and it works at a basin scale, requiring few input parameters that can be easily downloaded from global or government databases. Moreover, it is based on robust and unconditionally stable numerical techniques, and it guarantees the mass conservation. The proposed model was applied to four watersheds, two in the Southern Alps and two in the Southern Apennines, with catchment areas ranging from 5 to 48 km2. After the model calibration on the local geological context, a validation of the obtained results was accomplished considering different time intervals and the available sediment filling data. It was observed that the SMART-SED model, initially developed for the evaluation of fluvial hazard and of sediment transport in mountainous areas, was also suitable for the estimation of dam filling. Results indeed show a precise approximation of the order of magnitude of the cumulative sediment volume produced inside the catchments and transported to the water basins. In the framework of a complex problem affecting the production of “clean” energy in a changing world, SMART-SED could become a useful tool also for dam management
Relationship Between Short-Term Blood Pressure Variability and Subclinical Renal Damage in Essential Hypertensive Patients
The authors aimed to analyze the relationship between subclinical renal damage, defined as the presence of microalbuminuria or an estimated glomerular filtration rate (eGFR) between 30 mL/min/1.73 m(2) and 60 mL/min/1.73 m(2) and short-term blood pressure (BP) variability, assessed as average real variability (ARV), weighted standard deviation (SD) of 24-hour BP, and SD of daytime and nighttime BP. A total of 328 hypertensive patients underwent 24-hour ambulatory BP monitoring, 24-hour albumin excretion rate determination, and eGFR calculation using the Chronic Kidney Disease Epidemiology Collaboration equation. ARV of 24-hour systolic BP (SBP) was significantly higher in patients with subclinical renal damage (P=.001). This association held (P=.04) after adjustment for potential confounders. In patients with microalbuminuria, ARV of 24-hour SBP, weighted SD of 24-hour SBP, and SD of daytime SBP were also independently and inversely related to eGFR. These results seem to suggest that in essential hypertension, short-term BP variability is independently associated with early renal abnormalities
Novel Variant in Exon 3 of the BMP4 Gene Resulted in Ectopic Posterior Pituitary, Craniocervical Junction Dysmorphism and Limb Anomaly
Introduction. Pituitary differentiation involves a large number of transcription factors. In particular, BMP4 expression is fundamental for pituitary gland commitment from the ventral diencephalon, suppressing Shh expression in Rathke's pouch. Pathogenic variants in BMP4 are reported in the literature with a broad phenotypic spectrum, including pituitary and brain malformations. Case Presentation. A five-year-old girl came to medical attention following a mild cervical trauma with onset of cervical pain. On clinical examination at birth, postaxial polydactyly type B of the left hand was observed and removed at 10 months of age. A cervical radiography was performed, and a suspicion of craniocervical junction malformation was made. A magnetic resonance imaging of the cervical spine was made, showing an ectopic posterior pituitary, associated with dysmorphism of the craniocervical junction. The anthropometric parameters were pubertal Tanner stage 1, weight 16 kg (z-score: -1.09), height 107 cm (z-score: -0.76), and BMI 14 kg/m(2) (z-score: -0.92). Normal hormonal assessment was detected. Genetic analysis via next generation sequencing showed a novel de novo heterozygous variant (c.277 G > T, p.Glu93*) in exon 3 of BMP4. Discussion. We described a novel mutation in BMP4, resulting in ectopic posterior pituitary with normal hormonal assessment, associated to craniocervical junction dysmorphism and limb anomaly. It is important to monitor patient's growth and puberty and to screen the onset of symptoms related to the deficiency of one or more anterior as well as posterior pituitary hormones
Estimated clinical outcomes and cost-effectiveness associated with provision of addiction treatment in US primary care clinics
IMPORTANCE: US primary care practitioners (PCPs) are the largest clinical workforce, but few provide addiction care. Primary care is a practical place to expand addiction services, including buprenorphine and harm reduction kits, yet the clinical outcomes and health care sector costs are unknown.
OBJECTIVE: To estimate the long-term clinical outcomes, costs, and cost-effectiveness of integrated buprenorphine and harm reduction kits in primary care for people who inject opioids.
DESIGN, SETTING, AND PARTICIPANTS: In this modeling study, the Reducing Infections Related to Drug Use Cost-Effectiveness (REDUCE) microsimulation model, which tracks serious injection-related infections, overdose, hospitalization, and death, was used to examine the following treatment strategies: (1) PCP services with external referral to addiction care (status quo), (2) PCP services plus onsite buprenorphine prescribing with referral to offsite harm reduction kits (BUP), and (3) PCP services plus onsite buprenorphine prescribing and harm reduction kits (BUP plus HR). Model inputs were derived from clinical trials and observational cohorts, and costs were discounted annually at 3%. The cost-effectiveness was evaluated over a lifetime from the modified health care sector perspective, and sensitivity analyses were performed to address uncertainty. Model simulation began January 1, 2021, and ran for the entire lifetime of the cohort.
MAIN OUTCOMES AND MEASURES: Life-years (LYs), hospitalizations, mortality from sequelae (overdose, severe skin and soft tissue infections, and endocarditis), costs, and incremental cost-effectiveness ratios (ICERs).
RESULTS: The simulated cohort included 2.25 million people and reflected the age and gender of US persons who inject opioids. Status quo resulted in 6.56 discounted LYs at a discounted cost of 203 000-34 400 per LY). During a 5-year time horizon, BUP plus HR cost an individual PCP practice approximately $13 000.
CONCLUSIONS AND RELEVANCE: This modeling study of integrated addiction service in primary care found improved clinical outcomes and modestly increased costs. The integration of addiction service into primary care practices should be a health care system priority
Self-perceived physical level and fitness performance in children and adolescents with inflammatory bowel disease
Background: Inflammatory bowel disease (IBD) patients show a higher risk of developing metabolic and cardiovascular diseases due to the presence of systemic low-grade chronic inflammation. Exercise can improve cardiovascular fitness and modulate the inflammatory processes. We evaluated the physical activity (PA) level and the fitness performance of children and adolescents with IBD. Patients and methods: We considered 54 pediatric patients with IBD (14.6 ± 2.2; 22 M), including CD (n = 27) UC (n = 24) and IBD unclassified (n = 3), and 70 healthy children. In all children, the Physical Activity Questionnaire (PAQ-C) and the International Fitness Enjoyment Scale were self-reported and recorded. Results: PAQ-C showed significant difference in PA levels in patients with IBD compared to controls (p < 0.001). A decrease in general fitness (p = 0.003), cardiorespiratory fitness (p = 0.002), strength (p = 0.01), speed agility (p = 0.003), and flexibility (p = 0.01) were also detected between patients and controls. Speed agility was related to age (p = 0.02) and BMI z-score (p = 0.01), and flexibility to BMI z-score (p = 0.05). We noted a correlation between PA levels and physician global assessment (p = 0.021) and activity disease severity (p = 0.025). Conclusions: A poorer PA level and poor physical competence were found in patients with IBD compared to healthy children and adolescents. Monitored exercise could provide multiple benefits at both physical and psychological levels
Activation of Enteroendocrine Cells via TLRs Induces Hormone, Chemokine, and Defensin Secretion
Abstract
Enteroendocrine cells are known primarily for their production of hormones that affect digestion, but they might also be implicated in sensing and neutralizing or expelling pathogens. We evaluate the expression of TLRs and the response to specific agonists in terms of cytokines, defensins, and hormones in enteroendocrine cells. The mouse enteroendocrine cell line STC-1 and C57BL/6 mice are used for in vitro and in vivo studies, respectively. The presence of TLR4, 5, and 9 is investigated by RT-PCR, Western blot, and immunofluorescence analyses. Activation of these receptors is studied evaluating keratinocyte-derived chemokine, defensins, and cholecystokinin production in response to their specific agonists. In this study, we show that the intestinal enteroendocrine cell line STC-1 expresses TLR4, 5, and 9 and releases cholecystokinin upon stimulation with the respective receptor agonists LPS, flagellin, and CpG-containing oligodeoxynucleotides. Release of keratinocyte-derived chemokine and β-defensin 2 was also observed after stimulation of STC-1 cells with the three TLR agonists, but not with fatty acids. Consistent with these in vitro data, mice showed increased serum cholecystokinin levels after oral challenge with LPS, flagellin, or CpG oligodeoxynucleotides. In addition to their response to food stimuli, enteroendocrine cells sense the presence of bacterial Ags through TLRs and are involved in neutralizing intestinal bacteria by releasing chemokines and defensins, and maybe in removing them by releasing hormones such as cholecystokinin, which induces contraction of the muscular tunica, favoring the emptying of the distal small intestine
Predictors of drug prescription in nursing home residents: results from the INCUR study
Polypharmacy represents a major clinical and public health issue in older persons. We aimed to measure the prevalence of polypharmacy, and the main predictors of drug prescription in nursing home residents. Post hoc analyses of the "Incidence of pNeumonia and related ConseqUences in nursing home Residents" (INCUR) study were conducted. Polypharmacy was defined as the prescription of 5 or more drugs. A frailty index (FI) was computed according to the model proposed by Rockwood and Mitnitski using 36 health deficits, including diseases, signs, symptoms, and disabilities. Linear regression models were performed to identify the main predictors of the number of prescribed drugs. The INCUR study enrolled 800 patients (mean [SD] age 86.2 [4.1] years, 74.1% women). The mean number of medications prescribed at the baseline was 8.5 (SD 4.1). Prevalence of polypharmacy was found 86.4%. The mean FI was 0.38 (SD 0.10). A fully adjusted linear multivariate regression model found an inverse and independent association between age and number of prescribed drugs (beta - 0.07, 95% CI - 0.13, - 0.02; p = 0.005). Conversely, the FI was independently and positively associated with the number of medications (beta 4.73, 95% CI 1.17, 8.29; p = 0.009). The prevalence of polypharmacy is high among older persons living in nursing home. Age and FI are significantly associated with the number of drugs. The number of prescribed drugs tends to decrease with age, whereas a direct association with frailty is reported
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