687 research outputs found
Nitinol Carbofilm coated stents for peripheral applications: Study in the porcine model
Purpose: Testing the safety and foreign body reaction (FBR) of a nitinol self-expandable carbon-coated stent system in the porcine animal model at different follow-up (FU) periods. Methods: Fifteen minipigs received 30 carbon-coated self-expandable nitinol stents in iliac arteries. Explants were carried out at 7 (3 animals), 30 (4 animals), 90 (4 animals) and 180 (4 animals) day FU, for evaluation of acute, sub-acute and chronic biological response to the implanted devices. Histological, immunohistochemical, histomorphometric and scanning electron microscopy (SEM) analyses were performed to assess inflammatory reaction, endothelialization process, neointimal growth and cellular composition. Results: Thirty stents were successfully implanted. No mural thrombi were observed at gross examination or by angiography. Histologically no significant inflammatory reaction was detected: the stents appeared covered by a thin monolayer of endothelial cells even at 7 day FU. The neointima presented homogeneous growth and moderate thickness after 30, 90 and 180 days explants (0.38± 0.36 mm, 0.33± 0.30 mm, 0.27± 0.25 mm respectively). Internal and external elastic laminae were intact in 95% of stented arteries. Histological data validations of vessel endothelialization was obtained with SEM for the seven day follow-up group. Conclusions: This study showed good remarkable technical performances, minimal FBR and biocompatibility comparable with other available pre-clinical experimentation
Semilinear elliptic problems in : the interplay between the potential and the nonlinear term
It is considered a semilinear elliptic partial differential equation in
with a potential that may vanish at infinity and a nonlinear
term with subcritical growth. A positive solution is proved to exist depending
on the interplay between the decay of the potential at infinity and the
behavior of the nonlinear term at the origin. The proof is based on a
penalization argument, variational methods, and estimates. Those
estimates allow dealing with settings where the nonlinear source may have
supercritical, critical, or subcritical behavior near the origin. Results that
provide the existence of multiple and infinitely many solutions when the
nonlinear term is odd are also established
Saccharomyces cerevisiae-Based Probiotics as Novel Antimicrobial Agents to Prevent and Treat Vaginal Infections
Vaginal infections affect 70% of women during their lifetimes and account for millions of annual doctors' visits. These infections are predominantly represented by vulvovaginal candidiasis (VVC) and bacterial vaginosis (BV). Although standard antimicrobial agents remain the major strategy for the prevention and treatment of vaginal infections, both VVC and BV are difficult to treat due to high rates of resistance and recurrence, high probability of complications, and negative effects on the vaginal microbiota. This review focuses on a new approach of yeast-based probiotics for the prevention and/or treatment of these common vaginal infections
The imprints of the Galactic Bar on the Thick Disk with RAVE
We study the kinematics of a local sample of stars, located within a cylinder of 500 pc radius centered on the Sun, in the RAVE data set. We find clear asymmetries in the v R v∞ velocity distributions of thin and thick disk stars: there are more stars moving radially outward for low azimuthal velocities and more radially inward for high azimuthal velocities. Such asymmetries have been previously reported for the thin disk as being due to the Galactic bar, but this is the first time that the same type of structures are seen in the thick disk. Our findings imply that the velocities of thick-disk stars should no longer be described by Schwarzschilds, multivariate Gaussian or purely axisymmetric distributions. Furthermore, the nature of previously reported substructures in the thick disk needs to be revisited as these could be associated with dynamical resonances rather than to accretion events. It is clear that dynamical models of the Galaxy must fit the 3D velocity distributions of the disks, rather than the projected 1D, if we are to understand the Galaxy fully
Stillbirth occurrence during COVID-19 pandemic: A population-based prospective study
Objectives: Data collected worldwide on stillbirth (SB) rates during the Covid-19 pandemic are contradictory. Variations may be due to methodological differences or population characteristics. The aim of the study is to assess the changes in SB rate, risk factors, causes of death and quality of antenatal care during the pandemic compared to the control periods. Methods: This prospective study is based on the information collected by the Emilia-Romagna Surveillance system database. We conducted a descriptive analysis of SB rate, risk factors, causes of death and quality of cares, comparing data of the pandemic (March 2020-June 2021) with the 16 months before. Results: During the pandemic, the SB rate was 3.45/1,000 births, a value in line with the rates of previous control periods. Neonatal weight >90th centile was the only risk factor for SB that significantly changed during the pandemic (2.2% vs. 8.0%; p-value: 0.024). No significant differences were found in the distribution of the causes of death groups. Concerning quality of antenatal cares, cases evaluated with suboptimal care (5.2%) did not change significantly compared to the control period (12.0%), as well as the cases with less than recommended obstetric (12.6% vs. 14%) and ultrasound evaluations (0% vs. 2.7%). Conclusions: During the COVID-19 pandemic, no significant differences in SB rates were found in an area that maintained an adequate level of antenatal care. Thus, eventual associations between SB rate and the COVID-19 infection are explained by an indirect impact of the virus, rather than its direct effect
First-trimester prediction of gestational hypertension through the bioelectrical impedance analysis of the body composition
OBJECTIVE: Obesity is a risk factor for the development of gestational hypertension, with important consequences for both the mother and fetus. This prospective observational study aims to propose an early prediction model of hypertensive disorders in pregnancy among obese women, through the bioelectrical impedance analysis (BIA) at the first trimester, thus allowing early recognition of obese women that are at risk to develop gestational hypertension, in order to target preventive interventions. PATIENTS AND METHODS: Singleton obese women (BMI ≥ 30 kg/m2) between the 9th and 12th week of pregnancy were included in the study. The exclusion criteria were chronic diseases, like type 2 diabetes mellitus, hypertension, and other medical pre-existing conditions. Eligible women were followed up at 20, 28, and 36 weeks of gestation by measuring blood pressure, weight, and body composition with the use of the BIA. The diagnosis of gestational hypertension was made after the 20th week of gestation. Pregnancy and perinatal outcomes were then recorded. RESULTS: Of the 479 women included in the study, 85 (17.7%) developed gestational hypertension; the remaining 394 (82.3%) resulted to be normotensive. A higher rate of nulliparous women was found in the hypertensive group (50.6% vs. 37.6%, p = 0.02), together with a higher rate of induction of labor (55.3% vs. 40.9%, p = 0.02) and of small for gestational age (SGA) newborns (12.9% vs. 6.9%, p = 0.03). Significant differences emerged in the body composition between the two groups already from the first trimester, indeed women developing gestational hypertension showed elevated values of Total body Mass, FM, FFM, TBW (p < 0.02), and of leg's FM, FFM (p < 0.006). At the multivariate logistics regression, the risk of developing gestational hypertension resulted higher in women with elevated total body water levels in the first trimester (OR 1.10 95% CI 1.04 -1.92). CONCLUSIONS: The BIA is a rapid, easy, non-invasive, and inexpensive tool to evaluate the body composition of obese pregnant women. It represents a promising predictor of hypertensive disorders in pregnancy, which allows an early identification of the patients at risk of developing gestational hypertension, thus opening a window of opportunity for strictly monitoring and target preventive intervention
Resolving a guanine-quadruplex structure in the SARS-CoV-2 genome through circular dichroism and multiscale molecular modeling
The genome of SARS-CoV-2 coronavirus is made up of a single-stranded RNA fragment that can assume a specific secondary structure, whose stability can influence the virus's ability to reproduce. Recent studies have identified putative guanine quadruplex sequences in SARS-CoV-2 genome fragments that are involved in coding for both structural and non-structural proteins. In this contribution, we focus on a specific G-rich sequence referred to as RG-2, which codes for the non-structural protein 10 (Nsp10) and assumes a guanine-quadruplex (G4) arrangement. We provide the secondary structure of RG-2 G4 at atomistic resolution by molecular modeling and simulation, validated by the superposition of experimental and calculated electronic circular dichroism spectra. Through both experimental and simulation approaches, we have demonstrated that pyridostatin (PDS), a widely recognized G4 binder, can bind to and stabilize RG-2 G4 more strongly than RG-1, another G4 forming sequence that was previously proposed as a potential target for antiviral drug candidates. Overall, this study highlights RG-2 as a valuable target to inhibit the translation and replication of SARS-CoV-2, paving the way towards original therapeutic approaches against emerging RNA viruses.Parallel or hybrid? A combination of multiscale molecular modeling and circular dichroism is used to predict a G-quadruplex structure at atomistic resolution in the SARS-CoV-2 genome
Structure and Dynamics of RNA Guanine Quadruplexes in SARS-CoV-2 Genome. Original Strategies against Emerging Viruses
Guanine quadruplex (G4) structures in the viral genome have a key role in modulating viruses' biological activity. While several DNA G4 structures have been experimentally resolved, RNA G4s are definitely less explored. We report the first calculated G4 structure of the RG-1 RNA sequence of SARS-CoV-2 genome, obtained by using a multiscale approach combining quantum and classical molecular modeling and corroborated by the excellent agreement between the corresponding calculated and experimental circular dichroism spectra. We prove the stability of the RG-1 G4 arrangement as well as its interaction with G4 ligands potentially inhibiting viral protein translation
Induction of Labor According to Medical Indications: A Critical Evaluation through a Prospective Study
Background: The induction of labor (IOL) is a common obstetric intervention, steadily increasing (one out four pregnancies) in the last years. This procedure should be considered only when there is a medical indication, and when the benefits outweigh the maternal and/or fetal risks of waiting for spontaneous onset of labor. Therefore, this study aims to compare the efficacy of the IOL in terms of induction to delivery time, mode of delivery, and neonatal well-being among different evidence-based and non-evidence-based indications. Methods: This prospective study was conducted at the University Hospital of Modena, between January and December 2020. We included singleton pregnant women undergoing IOL, at the term. Intrauterine deaths, small for gestational age fetuses <5th centile as well women with hypertensive disorders were excluded. Women have been subdivided into 3 groups based on the indication to IOL: premature rupture of membranes (PROM), post-date pregnancy (>41 weeks + 3 days), and non-evidence-based indications (NEBI). The primary outcome is the time occurring between IOL and delivery (TIME), analyzing separately by parity. Moreover, mode of delivery and neonatal wellbeing were evaluated. Results: A total of 585 women underwent IOL in the study period. Overall, the median TIME between IOL and delivery was 19 hours, and the mean cesarean section CS rate was 15.5% (91/585). Pregnancies induced for postdate and non-evidencebased indications registered respectively a significantly higher mean time (p < 0.001), compared with women induced for PROM. This occurred both in nulliparous and multiparous women. Moreover, at multivariate analysis, the IOL TIME ≥24 hours was significantly influenced by Bishop score (p = 0.000) and NEBI (p = 0.02) in nulliparous and by gestational age (p = 0.000) and NEBI (p = 0.02) in multiparous. Moreover, CS rate was significantly influenced by Bishop score (p = 0.003) in nulliparous and by gestational age (p = 0.01) in multiparous. Finally, neonatal intensive care unit (NICU) admission resulted significantly influenced only by gestational age (p = 0.002) in multiparous. Conclusions: Our study confirms that IOL in non-evidence-based indications, leads to an increase in induction to delivery time comparing with women induced for PROM, both in nulliparous and multiparous women, thus it should be justified and carefully evaluated. Further randomized controlled trials (RCT) conducted in European/Italian settings are needed to determine the perinatal outcomes of IOL in non-evidence-based indications
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