Highly sensitive detection of the neurodegenerative biomarker Tau by using the concentration effect of the pyro-electrohydrodynamic jetting

It is largely documented that neurodegenerative diseases can be effectively treated only if early diagnosed. In this context, the structural changes of some biomolecules such as Tau, seem to play a key role in neurodegeneration mechanism becoming eligible targets for an early diagnosis. Post-translational modifications are responsible to drive the Tau protein towards a transition phase from a native disorder conformation into a preaggregation state, which then straight recruits the final fibrillization process. Here, we show for the first time the detection of pre-aggregated Tau in artificial urine at femto-molar level, through the concentration effect of the pyro-electrohydrodynamic jet (p-jet) technique. An excellent linear calibration curve is demonstrated at the femto-molar level with a limit of detection (LOD) of 130 fM. Moreover, for the first time we show here the structure stability of the protein after p-jet application through a deep spectroscopic investigation. Thanks to the small volumes required and the relatively compact and cost-effective characteristics, this technique represents an innovative breakthrough in monitoring the early stage associated to neurodegeneration syndromes in different scenarios of point of care (POC) and such as for example in long-term human space exploration missions.

Drop-on-Demand Pyro-Electrohydrodynamic Printing of Nematic Liquid Crystal Microlenses

Inkjet printing of liquid crystal (LC) microlens arrays is particularly appealing for the development of switchable 2D/3D organic light-emitting diode (OLED) displays, as the printing process ensures that the lenses can be deposited directly and on-demand onto the pixelated OLED layer without the need for additional steps, thus simplifying fabrication complexity. Even if different fabrication technologies have been employed and good results in LC direct printing have already been achieved, all the systems used require costly equipment and heated nozzles to reduce the LC solution's viscosity. Here, we present the direct printing of a nematic LC (NLC) lens by a Drop-on-Demand (DoD) inkjet printing by a pyro-electrohydrodynamic effect for the first time. The method works at ambient temperature and avoids dispensing nozzles, thus offering a noncontact manipulation approach of liquid with high resolution and good repeatability on different kinds of substrates. NLC microlenses are printed on different substrates and fully characterized. Polarization properties are evaluated for various samples, i.e., NLC lenses on unaligned and indium-tin oxide (ITO) aligned. Moreover, an in-depth characterization of the NLC lenses is reported by polarized optical microscopy and by analyzing the birefringence in digital holographic microscopy.

Primary malignant phyllodes tumors of the breast: A retrospective analysis from a referral center

BACKGROUND

The treatment for primary malignant phyllodes tumors of the breast (B-MPT) consists of wide local excision with negative margins (≥1 cm). However, because of their rarity, prognostic factors, type of surgery and adjuvant treatments are still a matter of debate.

METHODS

We conducted a single-center retrospective study to describe outcomes and prognostic factors of patients with primary B-MPT, who underwent breast surgery from January 2000 to December 2021. The primary endpoint was the cumulative incidence of any recurrence. Secondary endpoints were the cumulative incidences of distant and local recurrences.

RESULTS

131 patients were included, of whom all received surgery, 5 adjuvant anthracycline-based chemotherapy and 15 radiation therapy. After a median follow-up of 6.4 years, the cumulative incidences at 5-years of any, local and distant recurrences were of 26% (95% Confidence Interval [CI], 4-34%), 16% (95%CI, 10-24%) and 10% (95%CI, 5.3-16%), respectively. Tumor size ≥ 5 cm was associated with higher distant recurrences (p = 0.05); instead, among small tumors (<5 cm), distant recurrences were higher in those with heterologous differentiation and/or multifocal disease (p = 0.06). Type of breast surgery (mastectomy vs. lumpectomy/excision) was not found to be significantly associated with distant (p = 0.32) or local (p = 0.17) recurrence, even after controlling local recurrence incidence for negative pathologic prognostic factors (p = 0.17).

CONCLUSIONS

The natural history of B-MPT is burdened by local and distant recurrences. Pathologic prognostic factors (i.e., tumor size, heterologous differentiation and multifocal disease) more than the type of wide breast surgery (mastectomy vs. lumpectomy) seem to represent the most significant prognostic factor for recurrences.

Oscillation Dynamics of Dielectric Polymer Droplets during Electrohydrodynamic Jetting in a Wide Range of Viscosities

The electrohydrodynamic (EHD) jetting of fluids is used for several applications such as inkjet printing, atomization of analyte in mass spectrometry, liquid metal alloy ion sources, and electrospinning of polymer fibers. Historically, the bulk of research has focused on nonviscous, highly conductive fluids which are most suitable for EHD spray and printing, while there is relatively little experimental work on EHD jetting of highly viscous liquid dielectrics. We studied the dynamics of oscillation and pulsating jetting from a suspended drop of polydimethylsiloxane (PDMS) polymers in an electric field, with particular attention to the viscosity dependence of the oscillation period and meniscus elongation and contraction time over a wide viscosity range (102-105 cSt). The reported results could help the appropriate design of EHD processes and may open new possibilities for the rheological characterization of liquid polymers using small volumes at the scale of nanoliters.

Miniaturized, high numerical aperture confocal fluorescence detection enhanced with pyroelectric droplet accumulation for sub-attomole analyte diagnosis

To meet the growing demand for early fatal disease screening among large populations, current fluorescence detection instruments aiming at point-of-care diagnosis have the tendency to be low cost and high sensitivity, with a high potential for the analysis of low-volume, multiplex analytes with easy operation. In this work, we present the development of a miniaturized, high numerical aperture confocal fluorescence scanner for sub-micro-liter fluid diagnosis. It is enhanced with high-rate analyte accumulation using a pyroelectro-hydrodynamic dispensing system for generating tiny, stable sample droplets. The simplified confocal fluorescence scanner (numerical aperture 0.79, working distance 7.3 mm) uses merely off-the-shelf mass-production optical components. Experimental results show that it can achieve a high-sensitive, cost-efficient detection for sub-micro-liter, low-abundant (0.04 µL, 0.67 attomoles) fluid diagnosis, promising for point-of-care diagnosis.

Respiratory challenges and ventilatory management in different types of acute brain-injured patients

Acute brain injury (ABI) covers various clinical entities that may require invasive mechanical ventilation (MV) in the intensive care unit (ICU). The goal of MV, which is to protect the lung and the brain from further injury, may be difficult to achieve in the most severe forms of lung or brain injury. This narrative review aims to address the respiratory issues and ventilator management, specific to ABI patients in the ICU.

Genetic Alterations of Melanoma Brain Metastases: A Systematic Review and Meta-Analysis

BACKGROUND

Data on molecular alterations harbored by melanoma brain metastases (MBMs) are limited, and this has hampered the development of more effective therapeutic strategies. We conducted a systematic review and meta-analysis of all the studies reporting DNA sequencing data of MBMs, in order to identify recurrently mutated genes and molecular pathways significantly enriched for genetic alterations.

METHODS

We searched PubMed, Embase and Scopus for articles published from the inception of each database to June 30, 2021. We included in the analysis all the studies that reported individual patient data on DNA sequencing of MBMs, assessing single nucleotide variants (SNVs) and/or gene copy number variations (CNVs) in at least five tumor samples. Meta-analysis was performed for genes evaluated for SNVs and/or CNVs in at least two studies. Pooled proportions of samples with SNVs and/or CNVs was calculated by applying random-effect models based on the DerSimonian-Laird method. Gene-set enrichment analysis (GSEA) was performed to identify molecular pathways significantly enriched for mutated genes.

RESULTS

Ten studies fulfilled the inclusion criteria and were included in the analysis, for a total of 531 samples of MBMs evaluated. Twenty-seven genes were found recurrently mutated with a meta-analytic rate of SNVs higher than 5%. GSEA conducted on the list of these 27 recurrently mutated genes revealed vascular endothelial growth factor-activated receptor activity and transmembrane receptor protein tyrosine kinase activity to be among the top 10 gene ontology (GO) molecular functions significantly enriched for mutated genes, while regulation of apoptosis and cell proliferation were among the top 10 significantly enriched GO biological processes. Notably, a high meta-analytic rate of SNVs was found in several actionable cancer-associated genes, such as all the vascular endothelial growth factor (VEGF) receptor isoforms (i.e., Flt1 and Flt2 genes, for both SNV rate: 0.22, 95% CI 0.04-0.49; KDR gene, SNV rate: 0.1, 95% CI 0.05-0.16). Finally, two tumor suppressor genes were characterized by a high meta-analytic rate of CNVs: CDKN2A/B (CNV rate: 0.59, 95% CI 0.23-0.90) and PTEN (CNV rate: 0.31, 95% CI 0.02-0.95).

CONCLUSION

MBMs harbored actionable molecular alterations that could be exploited as therapeutic targets to improve the poor prognosis of patients.

Association of Anticancer Immune Checkpoint Inhibitors With Patient-Reported Outcomes Assessed in Randomized Clinical Trials: A Systematic Review and Meta-analysis

IMPORTANCE

The association of immune checkpoint inhibitors (ICIs) with patient quality of life has been poorly explored.

OBJECTIVE

To evaluate patient-reported outcomes (PROs) assessed in randomized clinical trials (RCTs) of immunotherapy-based treatments.

DATA SOURCES

This systematic review and random-effects meta-analysis used RCTs identified in PubMed, MEDLINE, Embase, and Scopus from database inception to June 1, 2021.

STUDY SELECTION

A total of 2259 RCTs were identified that assessed ICIs as monotherapy or in combination with chemotherapy or combined with another ICI and/or targeted therapy vs control groups not containing immunotherapy in patients with advanced solid tumors. Studies were reviewed independently by 2 authors.

DATA EXTRACTION AND SYNTHESIS

This meta-analysis followed the PRISMA guidelines and recommendations of the Setting International Standards in Analyzing Patient-Reported Outcomes and Quality of Life Endpoints Data Consortium.

MAIN OUTCOMES AND MEASURES

The coprimary aims of the meta-analysis were (1) pooled differences between treatment groups in the mean change of PRO score from baseline to 12 and 24 weeks of follow-up and (2) pooled differences between treatment groups in the time to deterioration of PRO score. For each end point, RCTs have been analyzed according to the type of treatment administered in the experimental group: ICIs given as monotherapy, ICIs combined with chemotherapy, or ICIs in association with another ICI and/or with targeted therapies.

RESULTS

Of the 2259 identified RCTs, 34 (18 709 patients) met the selection criteria and were analyzed. In the group of 19 RCTs testing ICIs as monotherapy, the pooled between-groups difference of mean change from baseline to 12 weeks of follow-up was 4.6 (95% CI, 2.8-6.4), and the mean change from baseline to 24 weeks of follow-up was 6.1 (95% CI, 4.2-8.1), significantly favoring ICIs. The pooled difference was 1.4 (95% CI, -0.4 to 3.2) at week 12 and 2.5 (95% CI, -0.8 to 5.9) at week 24 in the group of 8 RCTs testing ICIs combined with chemotherapy and 2.1 (95% CI, -0.8 to 5.0) at week 12 and 2.1 (95% CI, -0.4 to 4.5) at week 24 in the group of 8 RCTs testing other ICI-containing combinations. The time to deterioration was significantly longer in the immunotherapy-containing groups compared with control groups in all 3 groups of RCTs evaluated (hazard ratios of 0.80 [95% CI, 0.70-0.91] for ICIs as monotherapy, 0.89 [95% CI, 0.78-1.00] for ICIs plus chemotherapy, and 0.78 [95% CI, 0.63-0.96] for other ICI-containing combinations).

CONCLUSIONS AND RELEVANCE

Immune checkpoint inhibitors as monotherapy appear to have a favorable association with patient-reported quality of life and can be combined with other classes of anticancer drugs without worsening this quality of life.

Extracorporeal membrane oxygenation (ECMO) in COVID-19 patients: a pocket guide for radiologists

During the coronavirus disease 19 (COVID-19) pandemic, extracorporeal membrane oxygenation (ECMO) has been proposed as a possible therapy for COVID-19 patients with acute respiratory distress syndrome. This pictorial review is intended to provide radiologists with up-to-date information regarding different types of ECMO devices, correct placement of ECMO cannulae, and imaging features of potential complications and disease evolution in COVID-19 patients treated with ECMO, which is essential for a correct interpretation of diagnostic imaging, so as to guide proper patient management.

Respiratory and peripheral muscular ultrasound characteristics in ICU COVID 19 ARDS patients

PURPOSE

Severe cases of coronavirus disease 2019 develop ARDS requiring admission to the ICU. This study aimed to investigate the ultrasound characteristics of respiratory and peripheral muscles of patients affected by COVID19 who require mechanical ventilation.

MATERIALS AND METHODS

This is a prospective observational study. We performed muscle ultrasound at the admission of ICU in 32 intubated patients with ARDS COVID19. The ultrasound was comprehensive of thickness and echogenicity of both parasternal intercostal and diaphragm muscles, and cross-sectional area and echogenicity of the rectus femoris.

RESULTS

Patients who survived showed a significantly lower echogenicity score as compared with those who did not survive for both parasternal intercostal muscles. Similarly, the diaphragmatic echogenicity was significantly different between alive or dead patients. There was a significant correlation between right parasternal intercostal or diaphragm echogenicity and the cumulative fluid balance and urine protein output. Similar results were detected for rectus femoris echogenicity.

CONCLUSIONS

The early changes detected by echogenicity ultrasound suggest a potential benefit of proactive early therapies designed to preserve respiratory and peripheral muscle architecture to reduce days on MV, although what constitutes a clinically significant change in muscle echogenicity remains unknown.

Instant in situ formation of a polymer film at the water–oil interface

The water–oil interface is an environment that is often found in many contexts of the natural sciences and technological arenas. This interface has always been considered a special environment as it is rich in different phenomena, thus stimulating numerous studies aimed at understanding the abundance of physico-chemical problems that occur there. The intense research activity and the intriguing results that emerged from these investigations have inspired scientists to consider the water–oil interface even as a suitable setting for bottom-up nanofabrication processes, such as molecular self-assembly, or fabrication of nanofilms or nano-devices. On the other hand, biphasic liquid separation is a key enabling technology in many applications, including water treatment for environmental problems. Here we show for the first time an instant nanofabrication strategy of a thin film of biopolymer at the water–oil interface. The polymer film is fabricated in situ, simply by injecting a drop of polymer solution at the interface. Furthermore, we demonstrate that with an appropriate multiple drop delivery it is also possible to quickly produce a large area film (up to 150 cm²). The film inherently separates the two liquids, thus forming a separation layer between them and remains stable at the interface for a long time. Furthermore, we demonstrate the fabrication with different oils, thus suggesting potential exploitation in different fields (e.g. food, pollution, biotechnology). We believe that the new strategy fabrication could inspire different uses and promote applications among the many scenarios already explored or to be studied in the future at this special interface environment.

A completely new method for easy and quick formation of a thin polymer film at the special setting of a stratified oil/water interface. Morphological SEM and quantitative full-field characterization have been reported using digital holography.

A validation study of a continuous automatic measurement of the mechanical power in ARDS patients

The mechanical power (MP) is the energy delivered into the respiratory system over time. It can be computed as a direct measurement of the inspiratory area of the airway pressure and volume loop during the respiratory cycle or calculated by "power equations". The absence of a bedside computation limited its widespread use. Recently, it has been developed an automatic monitoring system inside of a mechanical ventilator.

PURPOSE

Our aim was to investigate the repeatability and the accuracy of the measured MP at different PEEP values and tidal volume compared with the calculated MP.

MATERIAL AND METHODS

MP was measured and calculated in sedated and paralyzed ARDS patients at low and high tidal volume, at 5-10-15 cmH₂O of PEEP both in volume and pressure-controlled ventilation. The same measurements were performed twice.

RESULTS

Fifty ARDS patients were enrolled. MP was measured and calculated for a total of 300 measurements. The bias and limits of agreement were 0.38 from -1.31 to 2.0 J/min. The measured and calculated MP were similar in each ventilatory condition.

CONCLUSIONS

The mechanical power measured by a new automatic real time system implemented in a mechanical ventilator was repeatable and accurate compared with the computed one.

Applying deep neural networks and inertial measurement unit in recognizing irregular walking differences in the real world

Falling injuries pose serious health risks to people of all ages, and knowing the extent of exposure to irregular surfaces will increase the ability to measure fall risk. Current gait analysis methods require overly complicated instrumentation and have not been tested for external factors such as walking surfaces that are encountered in the real-world, thus the results are difficult to extrapolate to real-world situations. Artificial intelligence approaches (in particular deep learning networks of varied architectures) to analyze data collected from wearable sensors were used to identify irregular surface exposure in a real-world setting. Thirty young adults wore six Inertial Measurement Unit (IMU) sensors placed on their body (right wrist, trunks at the L5/S1 level, left and right thigh, left and right shank) while walking over eight different surfaces commonly encountered in the living community as well as occupational settings. Three variations of deep learning models were trained to solve this walking surface recognition problem: 1) convolution neural network (CNN); 2) long short term memory (LSTM) network and 3) LSTM structure with an extra global pooling layer (Global-LSTM) which learns the coordination between different data streams (e.g. different channels of the same sensor as well as different sensors). Results indicated that all three deep learning models can recognize walking surfaces with above 0.90 accuracy, with the Global-LSTM yielding the best performance at 0.92 accuracy. In terms of individual sensors, the right thigh based Global-LSTM model reported the highest accuracy (0.90 accuracy). Results from this study provide further evidence that deep learning and wearable sensors can be utilized to recognize irregular walking surfaces induced motion alteration and applied to prevent falling injuries.

Jejunoileal diverticula: a broad spectrum of complications

BACKGROUND

Small bowel diverticula are a rare condition occurring mainly in the elderly. They can be isolated or multiple and can involve the duodenum, jejunum and ileum. Acute complications are extremely rare, with an aspecific pattern of symptoms. The aim of the study is to report the different patterns of presentation of patients with complicated jejunoileal diverticula.

METHODS

This is a retrospective descriptive study on a consecutive series of patients admitted for complicated jejunoileal diverticula in four Italian surgical departments between 2012 and 2019. Complications included acute diverticulitis, bleeding, perforation and intestinal obstruction. Patients presenting with complicated duodenal or Meckel's diverticula were not included.

RESULTS

Twenty-six patients were enrolled. The median age was 77 (46-94) years. Abdominal pain, fever and nausea/vomiting were the most frequent symptoms at presentation. Abdominal computed tomography (CT) was diagnostic in 35% of patients. Ten (38%) patients had bowel perforation, nine (35%) acute diverticulitis, five (19%) bowel obstruction and two (8%) had intestinal bleeding. Twenty-one (81%) patients underwent surgery, two (8%) were managed by CT-guided drainage of collections and three (11%) were treated with antibiotics. One patient died post-operatively. The median hospital stay was 9 (5-62) days.

CONCLUSION

Acutely complicated jejunoileal diverticula are infrequent, but a strong suspect should be raised whenever elderly patients are admitted for unspecific abdominal pain with a non-diagnostic CT scan. Conservative management may be offered in very selected cases if a diagnosis is obtained, but in most instances, surgery is both diagnostic and therapeutic.

Analysis of anaerobic digester mixing: comparison of long shafted paddle mixing vs gas mixing

The anaerobic digestion (AD) process is influenced by a variety of operation parameters, such as sludge rheology, mixing, temperature, solid retention time (SRT), hydraulic retention time (HRT) and solids concentration. The optimum in the mixing lies somewhere between no-mixing and continuous mixing, as the lack or excessive mixing can lead to poor AD performance instead. A three-dimensional computational fluid dynamics steady/unsteady model, incorporating the rheological properties of the sludge, was developed and applied to quantify mixing in a full-scale anaerobic digester. Mechanical and gas mixing solutions were taken into account, keeping constant the daily energy consumption. Results, consisting of velocity magnitude and patterns, dead zone formation and turbulence levels were discussed. Compared to the mechanical mixing, gas mixing had lower percentage of dead zones (about 5% against 50%), larger maximum velocity (about 3 m/s against 1 m/s) as well as larger turbulent kinetic energy levels (0.24 m²/s² against 0.001 m²/s²).

Quick liquid packaging: Encasing water silhouettes by three-dimensional polymer membranes

One of the most important substances on Earth is water. It is an essential medium for living microorganisms and for many technological and industrial processes. Confining water in an enclosed compartment without manipulating it or by using rigid containers can be very attractive, even more if the container is biocompatible and biodegradable. Here, we propose a water-based bottom-up approach for facile encasing of short-lived water silhouettes by a custom-made adaptive suit. A biocompatible polymer self-assembling with unprecedented degree of freedom over the water surface directly produces a thin membrane. The polymer film could be the external container of a liquid core or a free-standing layer with personalized design. The membranes produced have been characterized in terms of physical properties, morphology and proposed for various applications from nano- to macroscale. The process appears not to harm cells and microorganisms, opening the way to a breakthrough approach for organ-on-chip and lab-in-a-drop experiments.

Lung recruitment: What has computed tomography taught us in the last decade?

Although chest X-ray remains a fundamental lung imaging technique, through the years, CT scan has significantly improved our knowledge of the pathophysiological process and currently is the reference lung imaging tool for both a visual and quantitative computer-based analysis. The application of lung CT in the early phase of ARDS has led to changes in the clinical management in up of thirty percent of the patients. Although CT requires the transportation of the patient to the radiological department and exposes the patient to high dose of radiation, given the several information that CT can offer, it should be applied at least one time, in the early phase in all ARDS patients. CT plays an irreplaceable role to describe and assess the lung recruitability and to help a more physiological setting of mechanical ventilation.

On the Complex and Reversible Pathways of CdSe Quantum Dots Driven by Pyroelectric-Dielectrophoresis

Electrophoresis (EP) and dielectrophoresis (DEP) are the two well-established methodologies to manipulate nanoparticles (NPs). Recently, DEP by a virtual electrode platform was demonstrated on ferroelectric substrates, where the driving force is due to the strong electric field generated by the pyroelectric effect, thus opening new scenarios for manipulating the matter. Such an innovative approach named pyroelectric-DEP has several advantages over traditional EP and DEP. However, a detailed study on this novel approach is required for understanding the complex pathways traced by NPs under the action of the pyroelectric-driven forces and thus for explaining the final patterns. Here, we investigate experimentally the dynamic behavior of CdSe NPs through time-lapse fluorescence microscopy imaging. Complete visualization and measurement of the directed-assembling process of NPs immersed in polydimethylsiloxane fluid is reported, which shows some unpredicted results with respect to the previous works, thus opening the route for designing in principle a reversible and switchable device allowing two different and reversible final NP-patterned states. The observed phenomena are fully analyzed by experimental and simulated analysis, and the movements of NPs is performed to elucidate in depth the involved processes. The investigation furnishes an interesting result that the complex behavior of the NPs can be fully comprehended and explained by considering the superposition of both EP and DEP forces.

Easy Printing of High Viscous Microdots by Spontaneous Breakup of Thin Fibers

Electrohydrodynamic jetting is emerging as a successful technique for printing inks with resolutions well beyond those offered by conventional inkjet printers. However, the variety of printable inks is still limited to those with relatively low viscosities (typically <20 mPa s) due to nozzle clogging problems. Here, we show the possibility of printing ordered microdots of high viscous inks such as poly(lactic-co-glycolic acid) (PLGA) by exploiting the spontaneous breakup of a thin fiber generated through nozzle-free pyro-electrospinning. The PLGA fiber is deposited onto a partially wetting surface, and the breakup is achieved simply by applying an appropriate thermal stimulation, which is able to induce polymer melting and hence a mechanism of surface area minimization due to the Plateau-Rayleigh instability. The results show that this technique is a good candidate for extending the printability at the microscale to high viscous inks, thus extending their applicability to additional applications, such as cell behavior under controlled morphological constraints.

Endowing a plain fluidic chip with micro-optics: a holographic microscope slide

Lab-on-a-Chip (LoC) devices are extremely promising in that they enable diagnostic functions at the point-of-care. Within this scope, an important goal is to design imaging schemes that can be used out of the laboratory. In this paper, we introduce and test a pocket holographic slide that allows digital holography microscopy to be performed without an interferometer setup. Instead, a commercial off-the-shelf plastic chip is engineered and functionalized with this aim. The microfluidic chip is endowed with micro-optics, that is, a diffraction grating and polymeric lenses, to build an interferometer directly on the chip, avoiding the need for a reference arm and external bulky optical components. Thanks to the single-beam scheme, the system is completely integrated and robust against vibrations, sharing the useful features of any common path interferometer. Hence, it becomes possible to bring holographic functionalities out of the lab, moving complexity from the external optical apparatus to the chip itself. Label-free imaging and quantitative phase contrast mapping of live samples are demonstrated, along with flexible refocusing capabilities. Thus, a liquid volume can be analyzed in one single shot with no need for mechanical scanning systems.

Direct Writing of Microfluidic Footpaths by Pyro-EHD Printing

In this study, we report a direct writing method for the fabrication of microfluidic footpaths by pyro-electrohydrodynamic (EHD) jet printing. Here, we propose the use of a nozzle-free three-dimensional printing technique for the fabrication of printed structures that can be embedded in a variety of soft, transparent, flexible, and biocompatible polymers and thus easily integrated into lab-on-chip devices. We prove the advantage of the high resolution and flexibility of pyro-EHD printing for the realization of microfluidic channels well below the standard limit in dimension of conventional ink-jet printing technique and simply adaptable to the end-user desires in terms of geometry and materials. Starting from the description of the innovative approach proposed for the channel fabrication, we demonstrate the design, fabrication, and proof of a microfluidic matrix of interconnected channels. The method described here could be a breakthrough technology for the fabrication of in situ implantable, stretchable, and biocompatible devices, opening new routes in the field of biomedical engineering and wearable electronics.

Forward electrohydrodynamic inkjet printing of optical microlenses on microfluidic devices

We report a novel method for direct printing of viscous polymers based on a pyro-electrohydrodynamic repulsion system capable of overcoming limitations on the material type, geometry and thickness of the receiving substrate. In fact, the results demonstrate that high viscosity polymers can be easily manipulated for optical functionalizing of lab-on-a-chip devices through demonstration of direct printing of polymer microlenses onto microfluidic chips and optical fibre terminations. The present system has great potential for applications from biomolecules to nano-electronics. Moreover, in order to prove the effectiveness of the system, the optical performance of such microlenses has been characterized by testing their imaging capabilities when the fibroblast cells were allowed to flow inside the microfluidic channel, showing one of their possible applications on-board a LoC platform.

Maxillofacial trauma in the emergency department: pearls and pitfalls in airway management

Maxillofacial trauma poses a challenge for the anesthesiologist because injuries can often compromise the patient's airways. Airway maintenance is the first step in the American College of Surgeons Advance Trauma Life Support (ATLS®) protocol. However, clinical dilemmas may arise about the best way to manage a potentially life-threatening injury. There are no recommendations about the best time to intubate, the warning signs for deciding to intubate, or which device should be used when difficulty is expected. In this context the ATLS® approach is important but not sufficient. It is also necessary to recognize and be able to manage specific problems in this scenario where clinical priorities may be conflicting, may suddenly change or may be hidden. This clinical review discusses the complexity of this scenario, providing an overview of the conditions at greatest risk for airway obstruction and the options for airway management, on the basis of the recent literature. Clinicians must recognize the milestones and pitfalls of this topic in order to adopt a systematic approach for airway management, to identify specific characteristics associated with it, and to establish the utility of different instruments for airway management.

Glutamine Supplementation in Intensive Care Patients: A Meta-Analysis of Randomized Clinical Trials

The role of glutamine (GLN) supplementation in critically ill patients is controversial. Our aim was to analyze its potential effect in patients admitted to intensive care unit (ICU).We performed a systematic literature review through Medline, Embase, Pubmed, Scopus, Ovid, ISI Web of Science, and the Cochrane-Controlled Trials Register searching for randomized clinical trials (RCTs) published from 1983 to 2014 and comparing GLN supplementation to no supplementation in patients admitted to ICU. A random-effect meta-analysis for each outcome (hospital and ICU mortality and rate of infections) of interest was carried out. The effect size was estimated by the risk ratio (RR).Thirty RCTs were analyzed with a total of 3696 patients, 1825 (49.4%) receiving GLN and 1859 (50.6%) no GLN (control groups). Hospital mortality rate was 27.6% in the GLN patients and 28.6% in controls with an RR of 0.93 (95% CI = 0.81-1.07; P = 0.325, I = 10.7%). ICU mortality was 18.0 % in the patients receiving GLN and 17.6% in controls with an RR of 1.01 (95% CI = 0.86-1.19; P = 0.932, I = 0%). The incidence of infections was 39.7% in GLN group versus 41.7% in controls. The effect of GLN was not significant (RR = 0.88; 95% CI = 0.76-1.03; P = 0.108, I = 56.1%).These results do not allow to recommend GLN supplementation in a generic population of critically ills. Further RCTs are needed to explore the effect of GLN in more specific cohort of patients.

Early outcome of liver transplantation performed with organs procured from brain death donors with transient or sustained cardio-circulatory collapse

BACKGROUND

Aim of this study was to compare early graft function after transplantation of recipients transplanted with livers procured from donors after brain death who experienced transient or sustained cardio-circulatory collapse.

METHODS

We retrospectively analysed patients who underwent liver transplantation (LTx) at our Institution from January 2010 to May 2012. Recipients were divided into 3 groups: those who received livers from brain death donors who experienced reversible cardio-circulatory arrest before organ procurement (RCA); those who experienced sustained cardio-circulatory collapse, treated with extra-corporeal membrane oxygenation support as rescue therapy of refractory cardiogenic shock (ECMO). Standard donors were considered as reference group (REF). Postoperative graft function, Primary Non-Function (PNF), and complications during the first 30 days were analysed.

RESULTS

102 LTx were analysed (76 REF, 22 RCA and 4 ECMO). The main cause of donor's death was post-anoxic coma in RCA and ECMO, cerebrovascular accident in REF. SGOT in REF, RCA, and ECMO donors were 27 [17-43], 54 [34-92], 716 [190-962] respectively, SGPT 17 [12-34], 46 [27-73], 84 [51-175] UI/L respectively, both P<0.01. All recipients had similar SGOT (P=0.48), SGPT (P=0.75) and Model for End-Stage Liver Disease scores (P=0.98) before LTx; similar graft cold and warm ischemia time and serum lactate levels at the end of surgery. After LTx, Intensive Care Unit stay and the incidence of PNF were similar.

CONCLUSION

The use of livers procured from donors after brain death that experienced transient or sustained cardio-circulatory collapse was associated with early graft function comparable to that of standard donors.

Active accumulation of very diluted biomolecules by nano-dispensing for easy detection below the femtomolar range

Highly sensitive detection of biomolecules is of paramount interest in many fields including biomedicine, safety and eco-pollution. Conventional analyses use well-established techniques with detection limits ~1 pM. Here we propose a pyro-concentrator able to accumulate biomolecules directly onto a conventional binding surface. The operation principle is relatively simple but very effective. Tiny droplets are drawn pyro-electro-dynamically and released onto a specific site, thus increasing the sensitivity. The reliability of the technique is demonstrated in case of labelled oligonucleotides diluted serially. The results show the possibility to detect very diluted oligonucleotides, down to a few hundreds of attomoles. Excellent results are shown also in case of a sample of clinical interest, the gliadin, where a 60-fold improved detection limit is reached, compared with standard ELISA. This method could open the way to a mass-based technology for sensing molecules at very low concentrations, in environmental as well as in diagnostics applications.

Spontaneous assembly of carbon-based chains in polymer matrixes through surface charge templates

Stable chains of carbon-based nanoparticles were formed directly in polymer matrixes through an electrode-free approach. Spontaneous surface charges were generated pyroelectrically onto functionalized ferroelectric crystals, enabling the formation of electric field gradients that triggered the dipole-dipole interactions responsible for the alignment of the particles, while embedded in the polymer solution. The phenomenon is similar to the dielectrophoretic alignment of carbon nanotubes reported in the literature. However, here the electric fields are generated spontaneously by a simple heat treatment that, simultaneously, aligns the particles and provides the energy necessary for curing the host polymer. The result is a polymer sheet reinforced with well-aligned chains of carbon-based particles, avoiding the invasive implementation of appropriate electrodes and circuits. Because polymers with anisotropic features are of great interest for enhancing the thermal and/or the electrical conductivity, the electrode-free nature of this technique would improve the scaling down and the versatility of those interconnections that find applications in many fields, such as electronics, sensors, and biomedicine. Theoretical simulations of the interactions between the particles and the charge templates were implemented and appear in good agreement with the experimental results. The chain formation was characterized by controlling different parameters, including surface charge configuration, particle concentration, and polymer viscosity, thus demonstrating the reliability of the technique. Moreover, micro-Raman spectroscopy and scanning electron microscopy were used for a thorough inspection of the assembled chains.

Mechanistic evaluation of the transfection barriers involved in lipid-mediated gene delivery: interplay between nanostructure and composition

Here we present a quantitative mechanism-based investigation aimed at comparing the cell uptake, intracellular trafficking, endosomal escape and final fate of lipoplexes and lipid-protamine/deoxyribonucleic acid (DNA) (LPD) nanoparticles (NPs) in living Chinese hamster ovary (CHO) cells. As a model, two lipid formulations were used for comparison. The first formulation is made of the cationic lipid 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) and the zwitterionic lipid dioleoylphosphocholine (DOPC), while the second mixture is made of the cationic 3β-[N-(N,N-dimethylaminoethane)-carbamoyl] cholesterol (DC-Chol) and the zwitterionic helper lipid dioleoylphosphatidylethanolamine (DOPE). Our findings indicate that lipoplexes are efficiently taken up through fluid-phase macropinocytosis, while a less efficient uptake of LPD NPs occurs through a combination of both macropinocytosis and clathrin-dependent pathways. Inside the cell, both lipoplexes and LPD NPs are actively transported towards the cell nucleus, as quantitatively addressed by spatio-temporal image correlation spectroscopy (STICS). For each lipid formulation, LPD NPs escape from endosomes more efficiently than lipoplexes. When cells were treated with DOTAP-DOPC-containing systems the majority of the DNA was trapped in the lysosome compartment, suggesting that extensive lysosomal degradation was the rate-limiting factors in DOTAP-DOPC-mediated transfection. On the other side, escape from endosomes is large for DC-Chol-DOPE-containing systems most likely due to DOPE and cholesterol-like molecules, which are able to destabilize the endosomal membrane. The lipid-dependent and structure-dependent enhancement of transfection activity suggests that DNA is delivered to the nucleus synergistically: the process requires both the membrane-fusogenic activity of the nanocarrier envelope and the employment of lipid species with intrinsic endosomal rupture ability.

Graded-size microlens array by the pyro-electrohydrodynamic continuous printing method

In the present work, the pyro-electrohydrodynamic technique was used for the realization of tunable-size microlens arrays. Poly(methyl methacrylate) dissolved in different solvent mixtures was used as the polymeric material for the realization of the microstructures. By controlling the experimental parameters and in particular, the volume of the drop reservoir, graded-size square arrays of tens of microlenses with focal length in the range 1.5-3 mm were produced. Moreover, the optical quality and geometrical features were investigated by profilometric and interferometric analysis.

Colorectal liver metastasis with intrabiliary growth: case report and review of the literature

Colorectal liver metastases with intrabiliary growth are uncommon and difficult to characterize by radiology alone. We present the case of a 61-year-old woman previously operated on for a left colon cancer who developed a metacronous lesion at liver segment II-III. Radiologic workup was indicative for cholangiocarcinoma. Thus, the patient underwent an anatomical left lateral hepatectomy. Pathology showed instead a colorectal metastases with intrabiliary growth. We suggest that in cases of radiological uncertainty between an intrabiliary growth metastasis and a cholangiocarcinoma, the correct surgical strategy should always be an anatomical liver resection without preoperative biopsy because it would not change the operative planning and instead it may increase the risk of dissemination.

Noninvasive ventilation in chest trauma: systematic review and meta-analysis

PURPOSE

Single studies of Noninvasive Ventilation (NIV) in the management of acute respiratory failure in chest trauma patients have produced controversial findings. The aim of this study is to critically review the literature to investigate whether NIV reduces mortality, intubation rate, length of stay and complications in patients with chest trauma, compared to standard therapy.

METHODS

We performed a systematic review and meta-analysis of randomized controlled trials, prospective and retrospective observational studies, by searching PubMed, EMBASE and bibliographies of articles retrieved. We screened for relevance studies that enrolled adults with chest trauma who developed mild to severe acute respiratory failure and were treated with NIV. We included studies reporting at least one clinical outcome of interest to perform a meta-analysis.

RESULTS

Ten studies (368 patients) met the inclusion criteria and were included for the meta-analysis. Five studies (219 patients) reported mortality and results were quite homogeneous across studies, with a summary relative risk for patients treated with NIV compared with standard care (oxygen therapy and invasive mechanical ventilation) of 0.26 (95 % confidence interval 0.09-0.71, p = 0.003). There was no advantage in mortality of continuous positive airway pressure over noninvasive pressure support ventilation. NIV significantly increased arterial oxygenation and was associated with a significant reduction in intubation rate, in the incidence of overall complications and infections.

CONCLUSIONS

These results suggest that NIV could be useful in the management of acute respiratory failure due to chest trauma.