Adhesion to and biofilm formation on IB3-1 bronchial cells by Stenotrophomonas maltophilia isolates from cystic fibrosis patients

<p>Abstract</p> <p>Background</p> <p><it>Stenotrophomonas maltophilia </it>has recently gained considerable attention as an important emerging pathogen in cystic fibrosis (CF) patients. However, the role of this microorganism in the pathophysiology of CF lung disease remains largely unexplored. In the present study for the first time we assessed the ability of <it>S. maltophilia </it>CF isolates to adhere to and form biofilm in experimental infection experiments using the CF-derived bronchial epithelial IB3-1cell line. The role of flagella on the adhesiveness of <it>S. maltophilia </it>to IB3-1 cell monolayers was also assessed by using <it>fliI </it>mutant derivative strains.</p> <p>Results</p> <p>All <it>S. maltophilia </it>CF isolates tested in the present study were able, although at different levels, to adhere to and form biofilm on IB3-1 cell monolayers. Scanning electron and confocal microscopy revealed <it>S. maltophilia </it>structures typical of biofilm formation on bronchial IB3-1 cells. The loss of flagella significantly (P < 0.001) decreased bacterial adhesiveness, if compared to that of their parental flagellated strains. <it>S. maltophilia </it>CF isolates were also able to invade IB3-1 cells, albeit at a very low level (internalization rate ranged from 0.01 to 4.94%). Pre-exposure of IB3-1 cells to <it>P. aeruginosa </it>PAO1 significantly increased <it>S. maltophilia </it>adhesiveness. Further, the presence of <it>S. maltophilia </it>negatively influenced <it>P. aeruginosa </it>PAO1 adhesiveness.</p> <p>Conclusions</p> <p>The main contribution of the present study is the finding that <it>S. maltophilia </it>is able to form biofilm on and invade CF-derived IB3-1 bronchial epithelial cells, thus posing a rationale for the persistence and the systemic spread of this opportunistic pathogen in CF patients. Experiments using <it>in vivo </it>models which more closely mimic CF pulmonary tissues will certainly be needed to validate the relevance of our results.</p

Small Deletion at the 7q21.2 Locus in a CCM Family Detected by Real-Time Quantitative PCR

Cerebral cavernous malformations (CCMs) represent a common autosomal dominant disorder that predisposes patients to haemorrhagic strokes and focal neurological signs. About 56% of the hereditary forms of CCMs have been so far associated with mutations in the KRIT1 (Krev Interaction Trapped 1) gene, located at 7q21.2 (CCM1 locus). We described the complete loss of 7q21.2 locus encompassing the KRIT1 gene and 4 flanking genes in a CCM family by using a dense set of 12 microsatellite markers. The complete loss of the maternal copy of KRIT1 gene region was confirmed by Real-Time Quantitative Polymerase Chain Reaction (RT-QPCR) and the same approach was used for expression analysis. Additional RT-QPCR analysis showed the extension of the deletion, for a total of 700 kb, to the adjacent downstream and upstream-located genes, MTERF, AKAP9, CYP51A1, as well as a partial loss of the ANKIB1 gene. Here we report the molecular characterization of an interstitial small genomic deletion of the 7q21.2 region in a CCMs affected family, encompassing the KRIT1 gene. Our findings confirm the loss of function mechanism for the already known CCM1 locus, without any evident involvement of the other deleted genes. Moreover, our investigations highlight the usefulness of the RT-QPCR to the molecular characterization of the breakpoints genomic deletions and to the identification of internal deleted genes involved in the human genetic diseases

SATURN: A Technological Demonstration Mission for Distributed SAR Imaging

The OHB-Italia S.p.A-led consortium is in the midst of Phase B of SATURN (Synthetic AperTure radar cUbesat foRmation flyiNg), part of ALCOR, an Italian Space Agency (ASI) programme promoting the development of the next generation Italian CubeSats. SATURN is a demonstration mission that features Multiple-Input-Multiple-Output (MIMO) technology applied to a Swarm of CubeSats equipped with Synthetic Aperture Radar (SAR) for Earth Observation. MIMO is based on cooperative active sensors, where each one transmits signals and receives the illuminated common area backscatter related to the entire swarm, increasing measurement performances with a trend approximatively equal to the square of the number of sensors. The complete SATURN constellation features 16 mini-swarms, each of 3 CubeSats, spread over 4 SSOs equally spaced by 3 hours of local time. The constellation is designed to provide an average revisit time of 1.5 h and an interferometric revisit time of 1 day worldwide. The aim of this demonstration mission is to verify MIMO technology applied to SAR on a mini-swarm of 3 CubeSats in close formation on a Low Earth Down-Dusk Sun Synchronous Orbit. Using OHB-I’s M3Multi Mission Modular platform equipped with a miniaturized SAR Instrument, developed by ARESYS S.r.l. and Airbus Italia S.p.A., our mission is able to achieve a resolution of 5x5 m over a 30 km swath. Thus, SATURN enables low-cost, scalable SAR missions for affordable access to space for public and private entities, overcoming the single point of failure of one large and complex satellite. Subsequent swarms, deploying from 3 to 48 CubeSats, are expected to bring technological innovations and improve Italy’s competitiveness in the European and global Earth Observation scenario

Audiogenic epileptic DBA/2 mice strain as a model of genetic reflex seizures and SUDEP

Epilepsy is a chronic neurological disease characterized by abnormal brain activity, which results in repeated spontaneous seizures. Sudden unexpected death in epilepsy (SUDEP) is the leading cause of seizure-related premature death, particularly in drug-resistant epilepsy patients. The etiology of SUDEP is a structural injury to the brain that is not fully understood, but it is frequently associated with poorly controlled and repeated generalized tonic–clonic seizures (GTCSs) that cause cardiorespiratory and autonomic dysfunctions, indicating the involvement of the brainstem. Both respiratory and cardiac abnormalities have been observed in SUDEP, but not much progress has been made in their prevention. Owing to the complexity of SUDEP, experimental animal models have been used to investigate cardiac and/or respiratory dysregulation due to or associated with epileptic seizures that may contribute to death in humans. Numerous rodent models, especially mouse models, have been developed to better understand epilepsy and SUDEP physiopathology. This review synthesizes the current knowledge about dilute brown agouti coat color (DBA/2) mice as a possible SUDEP model because respiratory arrest (RA) and sudden death induced by audiogenic generalized seizures (AGSs) have been observed in these animals. Respiratory/cardiac dysfunction, brainstem arousal system dysfunction, and alteration of the neurotransmitter systems, which are observed in human SUDEP, have also been observed in these mice. In particular, serotonin (5-HT) alteration and adenosine neurotransmission appear to contribute to not only the pathophysiological mechanisms of medication but also seizure-related respiratory dysfunctions in this animal model. These neurotransmitter systems could be the relevant targets for medication development for chronic epilepsy and SUDEP prevention. We reviewed data on AGSs in DBA/2 mice and the relevance of this model of generalized tonic–clonic epilepsy to human SUDEP. Furthermore, the advantages of using this strain prone to AGSs for the identification of possible new therapeutic targets and treatment options have also been assessed

Initial Experience Using the New pHLO 0.072-inch Large-Bore Catheter for Direct Aspiration Thrombectomy in Acute Ischemic Stroke

Purpose A direct aspiration, first pass technique (ADAPT) has been introduced as a rapid and safe thrombectomy strategy in patients with intracranial large vessel occlusion (LVO). The aim of the study is to determine the technical feasibility, safety, and functional outcome of ADAPT using the newly released large bore pHLO 0.072-inch aspiration catheter (AC; Phenox). Materials and Methods We performed a retrospective analysis of data collected prospectively (October 2019–November 2021) from 2 comprehensive stroke centers. Accessibility of the thrombus, vascular recanalization, time to recanalization, and procedure-related complications were evaluated. National Institutes of Health stroke scale scores at presentation and discharge and the modified Rankin scale (mRS) score at 90 days post-procedure were recorded. Results Twenty-five patients (14 female, 11 male) with occlusions of the anterior circulation were treated. In 84% of cases, ADAPT led to successful recanalization with a median procedure time of 28 minutes. In the remaining cases, successful recanalization required (to a total of 96%; modified thrombolysis in cerebral infarction score 2b/3) the use of stent retrievers. No AC-related complications were reported. Other complications included distal migration of the thrombus, requiring a stent-retriever, and symptomatic PH2 hemorrhage in 16% and 4%, respectively. After 3 months, 52% of the patients had mRS scores of 0–2 with an overall mortality rate of 20%. Conclusion Results from our retrospective case series revealed that thrombectomy of LVOs with pHLO AC is safe and effective in cases of large-vessel ischemic stroke. Rates of complete or near-complete recanalization after the first pass with this method might be used as a new benchmark in future trials

Lopinavir/Ritonavir and Darunavir/Cobicistat in Hospitalized COVID-19 Patients: Findings From the Multicenter Italian CORIST Study

Background: Protease inhibitors have been considered as possible therapeutic agents for COVID-19 patients. Objectives: To describe the association between lopinavir/ritonavir (LPV/r) or darunavir/cobicistat (DRV/c) use and in-hospital mortality in COVID-19 patients. Study Design: Multicenter observational study of COVID-19 patients admitted in 33 Italian hospitals. Medications, preexisting conditions, clinical measures, and outcomes were extracted from medical records. Patients were retrospectively divided in three groups, according to use of LPV/r, DRV/c or none of them. Primary outcome in a time-to event analysis was death. We used Cox proportional-hazards models with inverse probability of treatment weighting by multinomial propensity scores. Results: Out of 3,451 patients, 33.3% LPV/r and 13.9% received DRV/c. Patients receiving LPV/r or DRV/c were more likely younger, men, had higher C-reactive protein levels while less likely had hypertension, cardiovascular, pulmonary or kidney disease. After adjustment for propensity scores, LPV/r use was not associated with mortality (HR = 0.94, 95% CI 0.78 to 1.13), whereas treatment with DRV/c was associated with a higher death risk (HR = 1.89, 1.53 to 2.34, E-value = 2.43). This increased risk was more marked in women, in elderly, in patients with higher severity of COVID-19 and in patients receiving other COVID-19 drugs. Conclusions: In a large cohort of Italian patients hospitalized for COVID-19 in a real-life setting, the use of LPV/r treatment did not change death rate, while DRV/c was associated with increased mortality. Within the limits of an observational study, these data do not support the use of LPV/r or DRV/c in COVID-19 patients

Different strategies for mechanical VENTilation during CardioPulmonary Bypass (CPBVENT 2014): Study protocol for a randomized controlled trial

Background: There is no consensus on which lung-protective strategies should be used in cardiac surgery patients. Sparse and small randomized clinical and animal trials suggest that maintaining mechanical ventilation during cardiopulmonary bypass is protective on the lungs. Unfortunately, such evidence is weak as it comes from surrogate and minor clinical endpoints mainly limited to elective coronary surgery. According to the available data in the academic literature, an unquestionable standardized strategy of lung protection during cardiopulmonary bypass cannot be recommended. The purpose of the CPBVENT study is to investigate the effectiveness of different strategies of mechanical ventilation during cardiopulmonary bypass on postoperative pulmonary function and complications. Methods/design: The CPBVENT study is a single-blind, multicenter, randomized controlled trial. We are going to enroll 870 patients undergoing elective cardiac surgery with planned use of cardiopulmonary bypass. Patients will be randomized into three groups: (1) no mechanical ventilation during cardiopulmonary bypass, (2) continuous positive airway pressure of 5 cmH2O during cardiopulmonary bypass, (3) respiratory rate of 5 acts/min with a tidal volume of 2-3 ml/Kg of ideal body weight and positive end-expiratory pressure of 3-5 cmH2O during cardiopulmonary bypass. The primary endpoint will be the incidence of a PaO2/FiO2ratio <200 until the time of discharge from the intensive care unit. The secondary endpoints will be the incidence of postoperative pulmonary complications and 30-day mortality. Patients will be followed-up for 12 months after the date of randomization. Discussion: The CPBVENT trial will establish whether, and how, different ventilator strategies during cardiopulmonary bypass will have an impact on postoperative pulmonary complications and outcomes of patients undergoing cardiac surgery. Trial registration: ClinicalTrials.gov, ID: NCT02090205. Registered on 8 March 2014