Physical and chemical mechanisms involved in adhesion of orthodontic bonding composites: in vitro evaluations

BackgroundBond strength of orthodontic composite is strongly influenced by molecular and structural mechanisms. Aim of this in vitro study was to compare bond strength of light-cure orthodontic composites by measuring debonding forces and evaluating locations of bond failure. Investigations on chemical compositions clarified adhesive behaviors and abilities, exploring effects of ageing processes in this junction materials.MethodsTwelve enamel discs, from human premolars, were randomly coupled to one orthodontic adhesive system (Transbond XT (TM) 3 M UNITEK, USA, Light-Cure Orthodontic Paste, LEONE, Italy and Bisco Ortho Bracket Paste LC, BISCO, Illinois) and underwent to Shear Bond Strength test. Metallic brackets were bonded to twenty-seven human premolar, with one of the adhesive systems, to quantify, at FE-SEM magnifications, after debonding, the residual material on enamel and bracket base surfaces. Raman Spectroscopy analysis was performed on eight discs of each composites to investigate on chemical compositions, before and after accelerated aging procedures in human saliva and sugary drink.ResultsOrthodontic adhesive systems showed similar strength of adhesion to enamel. The breakage of adhesive-adherent bond occurs in TXT at enamel-adhesive interface while in Bisco and Leone at adhesive-bracket interface. Accelerated in vitro aging demonstrated good physical-chemical stability for all composites, Bisco only, was weakly contaminated with respect to the other materials.ConclusionA similar, clinically adequate and acceptable bond strength to enamel for debonding maneuvers was recorded in all orthodontic adhesive systems under examination. No significant chemical alterations are recorded, even in highly critical situations, not altering the initial mechanical properties of materials

Translating proteomic into functional data: An high mobility group A1 (HMGA1) proteomic signature has prognostic value in breast cancer

Cancer is a very heterogeneous disease, and biological variability adds a further level of complexity, thus limiting the ability to identify new genes involved in cancer development. Oncogenes whose expression levels control cell aggressiveness are very useful for developing cellular models that permit differential expression screenings in isogenic contexts. HMGA1 protein has this unique property because it is a master regulator in breast cancer cells that control the transition from a nontumorigenic epithelial-like phenotype toward a highly aggressive mesenchymal-like one. The proteins extracted from HMGA1-silenced and control MDA-MB-231 cells were analyzed using label-free shotgun mass spectrometry. The differentially expressed proteins were cross-referenced with DNA microarray data obtained using the same cellular model and the overlapping genes were filtered for factors linked to poor prognosis in breast cancer gene expression meta-data sets, resulting in an HMGA1 protein signature composed of 21 members (HRS, HMGA1 reduced signature). This signature had a prognostic value (overall survival, relapse-free survival, and distant metastasis-free survival) in breast cancer. qRT-PCR, Western blot, and immunohistochemistry analyses validated the link of three members of this signature (KIFC1, LRRC59, and TRIP13) with HMGA1 expression levels both in vitro and in vivo and wound healing assays demonstrated that these three proteins are involved in modulating tumor cell motility. Combining proteomic and genomic data with the aid of bioinformatic tools, our results highlight the potential involvement in neoplastic transformation of a restricted list of factors with an as-yet-unexplored role in cancer. These factors are druggable targets that could be exploited for the development of new, targeted therapeutic approaches in triple-negative breast cancer

Echocardiography-guided management of preterms with patent ductus arteriosus influences the outcome: a cohort study

Introduction: Echocardiography (ECHO) with color flow Doppler is considered as the gold standard to identify a hemodynamic patent ductus arteriosus (hs-PDA). However, the optimal diagnostic and therapeutic management for newborns with hs-PDA is still controversial. We aimed to investigate two clinical strategies: (1) targeted treatment based on ECHO criteria and (2) treatment based on ECHO criteria in addition to clinical signs and symptoms. Materials and Methods: This is a cohort study including all neonates consecutively admitted in the Neonatal Intensive Care Unit of University La Sapienza in Rome, with gestational age <32 weeks or body birth weight <1,500 g and with a diagnosis of hs-PDA as confirmed by ECHO evaluation performed within 72 h of life. We classified the babies in two cohorts: (A) pharmacological treatment immediately after ECHO screening and (B) pharmacological therapy for PDA was administered when the relevance of a hs-PDA was associated with clinical signs of hemodynamic instability. Results: We considered as primary outcome newborns who survived without any morbidities (A: 48.1% vs. B: 22.2%, p = 0.022). In particular, we found that the rate of intraventricular hemorrhage stage ≥2 was increased in cohort B (A: 3.7% vs. B 24.4%, p = 0.020). A multivariate analysis showed that assignment to cohort A independently influences the primary outcome. Conclusions: Adopting an hs-PDA management option based on ECHO-directed therapy regardless of symptoms may reduce the morbidity and improve the survival of very low birth weight infants

Umbilical cord medication in healthy full-term newborns: a before-after uncontrolled quality improvement study

Umbilical cord care can be a stressful practice for parents. Complications of cord care can increase neonatal morbidity and mortality. The extracts of Arnica montana (AM) have been reported to possess antibacterial, anti-inflammatory, antifungal, and immunomodulatory activities. We aim to demonstrate the efficacy of AM on cord detachment and parents’ stress level induced by cord medication in healthy full-term newborns. We enrolled full-term infants with a birth weight ≥ 2500 g in healthy conditions. Cord stumps of infants in the PRE-group were cleaned and dried, while cord stumps of infants in the POST-group were cleaned, dried, and medicated with a natural topic dermo-protective powder containing AM. After discharge, we interviewed parents on the stump status during follow-up visits in a pediatric office at 7 and 14 days of life, or by phone calls after follow-up visits. Long-rank test showed that time of cord separation of newborns in the PRE-group was significantly higher compared to that in the POST-group (p < 0.001). Parents of newborns in the PRE-group were significantly more stressed during cord medication compared to parents in the POST-group (2.0 (1.2 to 2.1) vs 1.0 (0.8 to 1.3), p = 0.011). Multivariate analysis showed a significantly linear relation with group assignment for cord separation (p < 0.001) and parents’ stress during the medication (p = 0.033). Conclusion: The use of a natural topic dermo-protective powder containing AM reduces the time of cord separation, improves parents’ stress level, and reduces the risk of complications

An observational study to assess Italian obstetrics providers' knowledge about preventive practices and diagnosis of congenital cytomegalovirus

Congenital cytomegalovirus (cCMV) infection can be easily prevented by hygienic measures. Up to date the majority of the studies in literature highlighted a reduction in cCMV antenatal counseling and its prevention. Our purpose was to evaluate obstetrics providers' knowledge about cCMV infection, management and the behavioral practices to avoid it. This is a cross-sectional survey carried out in Umberto I Hospital, "Sapienza"University of Rome between November 2019 and January 2020. We recruited 148 specialists and residents in Obstetrics and Gynecology through online anonymous multiple-choice 13-questions, 10 min-survey comparing responses between the two groups. A total of 94.6% of all participants said they always prescribe cytomegalovirus (CMV) serum screening: 73.6% of them regularly counsel about preventive practices, with specialists recording higher percentages (85.4 vs. 65.1%, p<0.005). We identified a good knowledge about the diagnostic pathway, but only 58.1% of our population knows the correct time of late amniocentesis. 12.2% of providers do not consider magnetic resonance (MRI) as a complementary exam. Prevention of maternal seroconversion is crucial: even if our data show an acceptable knowledge about antenatal counseling, we encourage clinicians to firmly inform and educate women about behavioral measures

Rescue of Replication-Competent ZIKV Hidden in Placenta-Derived Mesenchymal Cells Long After the Resolution of the Infection

The Zika virus (ZIKV) genome, its negative-strand viral proteins, and virus-like particles were detected in placenta-derived mesenchymal cells (MSCs), indicating that ZIKV persists after virus clearance from maternal blood and can be rescued by in vitro cultivation. We report for the first time the presence of replication-competent ZIKV in MSCs from an asymptomatic woman who acquired infection during pregnancy

A function blocking anti-mouse integrin α5β1 antibody inhibits angiogenesis and impedes tumor growth in vivo

<p>Abstract</p> <p>Background</p> <p>Integrins are important adhesion molecules that regulate tumor and endothelial cell survival, proliferation and migration. The integrin α5β1 has been shown to play a critical role during angiogenesis. An inhibitor of this integrin, volociximab (M200), inhibits endothelial cell growth and movement <it>in vitro</it>, independent of the growth factor milieu, and inhibits tumor growth <it>in vivo </it>in the rabbit VX2 carcinoma model. Although volociximab has already been tested in open label, pilot phase II clinical trials in melanoma, pancreatic and renal cell cancer, evaluation of the mechanism of action of volociximab has been limited because this antibody does not cross-react with murine α5β1, precluding its use in standard mouse xenograft models.</p> <p>Methods</p> <p>We generated a panel of rat-anti-mouse α5β1 antibodies, with the intent of identifying an antibody that recapitulated the properties of volociximab. Hybridoma clones were screened for analogous function to volociximab, including specificity for α5β1 heterodimer and blocking of integrin binding to fibronectin. A subset of antibodies that met these criteria were further characterized for their capacities to bind to mouse endothelial cells, inhibit cell migration and block angiogenesis <it>in vitro</it>. One antibody that encompassed all of these attributes, 339.1, was selected from this panel and tested in xenograft models.</p> <p>Results</p> <p>A panel of antibodies was characterized for specificity and potency. The affinity of antibody 339.1 for mouse integrin α5β1 was determined to be 0.59 nM, as measured by BIAcore. This antibody does not significantly cross-react with human integrin, however 339.1 inhibits murine endothelial cell migration and tube formation and elicits cell death in these cells (EC₅₀= 5.3 nM). In multiple xenograft models, 339.1 inhibited the growth of established tumors by 40–60% (<it>p </it>< 0.05) and this inhibition correlates with a concomitant decrease in vessel density.</p> <p>Conclusion</p> <p>The results herein demonstrate that 339.1, like volociximab, exhibits potent anti-α5β1 activity and confirms that inhibition of integrin α5β1 impedes angiogenesis and slows tumor growth <it>in vivo</it>.</p