Comb-assisted cavity ring-down spectroscopy of a buffer-gas-cooled molecular beam

We demonstrate continuous-wave cavity ring-down spectroscopy of a partially hydrodynamic molecular beam emerging from a buffer-gas-cooling source. Specifically, the (ν1 + ν3) vibrational overtone band of acetylene (C2H2) around 1.5 μm is accessed using a narrow-linewidth diode laser stabilized against a GPS-disciplined rubidium clock via an optical frequency comb synthesizer. As an example, the absolute frequency of the R(1) component is measured with a fractional accuracy of ∼1 × 10(-9). Our approach represents the first step towards the extension of more sophisticated cavity-enhanced interrogation schemes, including saturated absorption cavity ring-down or two-photon excitation, to buffer-gas-cooled molecular beams

Experimental observation of optical frequency combs in doubly resonant second harmonic generation

Continuously-driven microresonators, whose nonlinear response is dominated by the third-order Kerr nonlinearity, have proven to be valid alternatives to comb sources based on femtosecond mode-locked lasers [1]. More recenlty, the direct generation of optical frequency combs (OFCs) entirely through quadratic interactions has also been demonstrated in singly resonant cavity second harmonic generation (SHG) and in cw pumped nearly degenerate optical parametric oscillation [2,3]. Interestingly, theoretical studies on doubly resonant cavity SHG predicted the emergence of OFCs with a much lower threshold with respect to the singly resonant configurations, as well as rich nonlinear dynamics [4]

Placental Circulation Intact Trial (PCI-T)—Resuscitation With the Placental Circulation Intact vs. Cord Milking for Very Preterm Infants: A Feasibility Study

Background: Preterm newborns receiving briefly delayed cord clamping or cord milking at birth have better neonatal outcomes. However, the time frame in which both these procedures are performed (< 60 s of life) is too short to explore the possible beneficial effects on early infant postnatal adaptation and outcomes of a prolonged transfusion strategy associated with neonatal respiration.Methods and Design: We have designed a randomized, multicenter, controlled two-phase study: phase 1 to assess the feasibility of carrying out the protocol in a large randomized trial, and phase 2 to assess the efficacy of bedside assistance with intact placental circulation for 3 min in comparison to cord milking to improve outcome in the neonatal period; we present here the feasibility and safety phase of the study. Outcomes included feasibility (recruitment rate of two patients per month, compliance with the trial interventions, completeness of data collection, >90% of infants receiving echographic assessments in the first 24 h) and safety variables (5 min Apgar score, delivery room intubation rate, CRIB II score, admission temperature, maximum hemoglobin concentration and hematocrit in the first 24 h and maximum serum bilirubin value) in the two study groups. We also evaluated the same safety variables in infants delivered during the study period but not recruited.Results: A total of 40 infants were enrolled. In all cases the protocol was completed and all feasibility outcomes were reached. Infants assisted with an intact placental circulation have a higher 5 min Apgar score but their admission temperature was lower than milked infants. Delivery room intubation rate, CRIB II score and peak serum bilirubin value were comparable in both groups. Infants who were not subjected to a placental transfusion strategy (excluded patients) had a higher delivery room intubation rate with respect to both study groups.Conclusion: Delaying cord clamping until 3 min of life was challenging but feasible and appeared to be safe. However, admission temperature must be strictly monitored and a more efficacious warming system could be implemented to prevent hypothermia during the procedure.Trial Registration: Clinicaltrials,gov NCT02671305 (date of registration: 26 JAN 2016). https://clinicaltrials.gov/ct2/show/NCT0267130

Immunotherapy in Pancreatic Cancer: Why Do We Keep Failing? A Focus on Tumour Immune Microenvironment, Predictive Biomarkers and Treatment Outcomes

The advent of immunotherapy and targeted therapies has dramatically changed the outcomes of patients affected by many malignancies. Pancreatic cancer (PC) remains one the few tumors that is not treated with new generation therapies, as chemotherapy still represents the only effective therapeutic strategy in advanced-stage disease. Agents aiming to reactivate the host immune system against cancer cells, such as those targeting immune checkpoints, failed to demonstrate significant activity, despite the success of these treatments in other tumors. In many cases, the proportion of patients who derived benefits in early-phase trials was too small and unpredictable to justify larger studies. The population of PC patients with high microsatellite instability/mismatch repair deficiency is currently the only population that may benefit from immunotherapy; nevertheless, the prevalence of these alterations is too low to determine a real change in the treatment scenario of this tumor. The reasons for the unsuccess of immunotherapy may lie in the extremely peculiar tumor microenvironment, including distinctive immune composition and cross talk between different cells. These unique features may also explain why the biomarkers commonly used to predict immunotherapy efficacy in other tumors seem to be useless in PC. In the current paper, we provide a comprehensive and up-to-date review of immunotherapy in PC, from the analysis of the tumor immune microenvironment to immune biomarkers and treatment outcomes, with the aim to highlight that simply transferring the knowledge acquired on immunotherapy in other tumors might not be a successful strategy in patients affected by PC

Molecular origin of the two-step mechanism of gellan aggregation

Among hydrocolloids, gellan is one of the most studied polysaccharides due to its ability to form mechanically stable gels. Despite its long-standing use, the gellan aggregation mechanism is still not understood because of the lack of atomistic information. Here, we fill this gap by developing a new gellan force field. Our simulations offer the first microscopic overview of gellan aggregation, detecting the coil to single-helix transition at dilute conditions and the formation of higher-order aggregates at high concentration through a two-step process: first, the formation of double helices and then their assembly into superstructures. For both steps, we also assess the role of monovalent and divalent cations, complementing simulations with rheology and atomic force microscopy experiments and highlighting the leading role of divalent cations. These results pave the way for future use of gellan-based systems in a variety of applications, from food science to art restoration

Mixed connective tissue disease : state of the art on clinical practice guidelines

© Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.Mixed connective tissue disease (MCTD) is a complex overlap disease with features of different autoimmune connective tissue diseases (CTDs) namely systemic sclerosis, poly/dermatomyositis and systemic lupus erythematous in patients with antibodies targeting the U1 small nuclear ribonucleoprotein particle. In this narrative review, we summarise the results of a systematic literature research which was performed as part of the European Reference Network on Rare and Complex Connective Tissue and Musculoskeletal Diseases project, aimed at evaluating existing clinical practice guidelines (CPGs) or recommendations. Since no specific CPGs on MCTD were found, other CPGs developed for other CTDs were taken into consideration in order to discuss what can be applied to MCTD even if designed for other diseases. Three major objectives were proposed for the future development of CPGs: MCTD diagnosis (diagnostic criteria), MCTD initial and follow-up evaluations, MCTD treatment. Early diagnosis, epidemiological data, assessment of burden of disease and QOL aspects are among the unmet needs identified by patients.This publication was funded by the European Union’s Health Programme (2014-2020)info:eu-repo/semantics/publishedVersio