Electro-Mechanical Characterization and Modeling of a Broadband Piezoelectric Microgenerator Based on Lithium Niobate.

Vibration energy harvesting based on piezoelectric transducers is an attractive choice to replace single-use batteries in powering Wireless Sensor Nodes (WSNs). As of today, their widespread application is hindered due to low operational bandwidth and the conventional use of lead-based materials. The Restriction of Hazardous Substances legislation (RoHS) implemented in the European Union restricts the use of lead-based piezoelectric materials in future electronic devices. This paper investigates lithium niobate (LiNbO3) as a lead-free material for a high-performance broadband Piezoelectric Energy Harvester (PEH). A single-clamped, cantilever beam-based piezoelectric microgenerator with a mechanical footprint of 1 cm2, working at a low resonant frequency of 200 Hz, with a high piezoelectric coupling coefficient and broad bandwidth, was designed and microfabricated, and its performance was evaluated. The PEH device, with an acceleration of 1 g delivers a maximum output RMS power of nearly 35 µW/cm2 and a peak voltage of 6 V for an optimal load resistance at resonance. Thanks to a high squared piezoelectric electro-mechanical coupling coefficient (k2), the device offers a broadband operating frequency range above 10% of the central frequency. The Mason electro-mechanical equivalent circuit was derived, and a SPICE model of the device was compared with experimental results. Finally, the output voltage of the harvester was rectified to provide a DC output stored on a capacitor, and it was regulated and used to power an IoT node at an acceleration of as low as 0.5 g.

Integrated Approach of Life Cycle Assessment and Experimental Design in the Study of a Model Organic Reaction: New Perspectives in Renewable Vanillin-Derived Chemicals.

This work is focused on performing a quantitative assessment of the environmental impacts associated with an organic synthesis reaction, optimized using an experimental design approach. A nucleophilic substitution reaction was selected, employing vanillin as the substrate, a phenolic compound widely used in the food industry and of pharmaceutical interest, considering its antioxidant and antitumoral potential. To carry out the reaction, three different solvents have been chosen, namely acetonitrile (ACN), acetone (Ace), and dimethylformamide (DMF). The syntheses were planned with the aid of a multivariate experimental design to estimate the best reaction conditions, which simultaneously allow a high product yield and a reduced environmental impact as computed by Life Cycle Assessment (LCA) methodology. The experimental results highlighted that the reactions carried out in DMF resulted in higher yields with respect to ACN and Ace; these reactions were also the ones with lower environmental impacts. The multilinear regression models allowed us to identify the optimal experimental conditions able to guarantee the highest reaction yields and lowest environmental impacts for the studied reaction. The identified optimal experimental conditions were also validated by experimentally conducting the reaction in those conditions, which indeed led to the highest yield (i.e., 93%) and the lowest environmental impacts among the performed experiments. This work proposes, for the first time, an integrated approach of DoE and LCA applied to an organic reaction with the aim of considering both conventional metrics, such as reaction yield, and unconventional ones, such as environmental impacts, during its lab-scale optimization.

A guide for kernel generalized regression methods for genomic-enabled prediction.

The primary objective of this paper is to provide a guide on implementing Bayesian generalized kernel regression methods for genomic prediction in the statistical software R. Such methods are quite efficient for capturing complex non-linear patterns that conventional linear regression models cannot. Furthermore, these methods are also powerful for leveraging environmental covariates, such as genotype × environment (G×E) prediction, among others. In this study we provide the building process of seven kernel methods: linear, polynomial, sigmoid, Gaussian, Exponential, Arc-cosine 1 and Arc-cosine L. Additionally, we highlight illustrative examples for implementing exact kernel methods for genomic prediction under a single-environment, a multi-environment and multi-trait framework, as well as for the implementation of sparse kernel methods under a multi-environment framework. These examples are followed by a discussion on the strengths and limitations of kernel methods and, subsequently by conclusions about the main contributions of this paper.

Management of Asbestos Containing Materials: A Detailed LCA Comparison of Different Scenarios Comprising First Time Asbestos Characterization Factor Proposal.

This work addresses the complex issue of asbestos containing materials (ACMs) management, by focusing on the scenario of six municipalities comprised in the Reggio Emilia province of Emilia Romagna Italian region. Particularly, the life cycle assessment (LCA) methodology was applied in order to assess in a quantitative and reliable manner the human toxicity as well as the ecotoxicity impacts associated with all of the different phases of ACMs management. The latter comprises mapping of ACMs, creation of a risk map for defining priority of intervention, encapsulation and removal of ACMs, as well as the as obtained asbestos containing waste (ACW) end of life. Particularly, a thermal inertisation treatment performed in a continuous industrial furnace was considered as the innovative end of life scenario to be compared with what actually was provided by the legislation of many countries worldwide, that is, the disposal of ACW in a controlled landfill for hazardous wastes. A characterization factor for asbestos fibers released both in outdoor air and in occupational setting was proposed for the first time and included in the USEtox 2.0 impact assessment method. This allowed us to reliably and quantitatively highlight that inertisation treatments should be the preferred solutions to be adopted by local and national authorities, especially if the obtained inert material finds application as secondary raw materials, thus contributing to a decrease in the environmental damage (limited to its toxicological contributions) to be associated with asbestos management.

Cost analysis of a long-term randomized controlled study in biliary duct-to-duct anastomotic stricture after liver transplantation.

Multiple plastic stent (MPS) for biliary anastomotic stricture (AS) after liver transplantation requires multiple procedures with consequent costs. To compare the success, adverse events and treatment-related costs of fully covered self-expandable metal stents (FCSEMS) versus MPS. Thirty liver transplant (LT) patients with clinically relevant naïve AS were prospectively randomized to FCSEMS or MPS, with stent numbers increased at 3-month intervals. Treatment costs per patient were calculated for endoscopic retrograde cholangiopancreatography (including all devices and stents) and overall hospital stay. Radiological success was achieved in 73% of FCSEMS (median indwelling period of 6 mos) and 93% of MPS patients (P = NS) (median period of 11 mos). AS recurrence occurred in 36% of FCSEMS and 7% of MPS patients (P = NS), and AS re-treatment was needed in 53% and 13% (P < 0.01), respectively, during follow-up of 60 (34-80) months. Stents migrated after 29% and 2.6% of FCSEMS and MPS procedures, respectively (P < 0.01). Including re-treatments, long-term clinical success was achieved in 28/30 (93%) patients. Overall treatment-related costs were similar between groups. In the subgroup of LT patients in clinical remission after first-line treatment, treatment costs were 41% lower per FCSEMS patient compared with MPS patients. FCSEMS did not perform better than MPS. FCSEMS migration increased the rate of re-treatment and costs.

Expanding endoscopic treatment strategies for pancreatic leaks following pancreato-duodenectomy: a single centre experience.

BACKGROUND AND AIM: Clinically relevant pancreatic leaks of jejunal-pancreatic anastomosis after pancreato-duodenectomy (PD) occur in 9-15% of cases. Endoscopic strategies for management of pancreatic fistula, may allow to avoid reoperation and shorten times for fistula closure, but are still understudied and not widely performed. Aim of the present paper is to describe different endoscopic techniques used to treat such conditions. METHODS: It was a retrospective, single centre, study. All patients who underwent endoscopic treatment for pancreatic leaks following PD between 1st January 2013 and 31th May 2019 at our Centre were reviewed. Depending on the morphology and severity of the leak, four main endoscopic techniques were performed: (1) trans-anastomotic intraductal pancreatic stent insertion; (2) lumen-apposing metal stent between the jejunal loop and the retroperitoneum toward the pancreatic stump insertion ("yoyo-stent"); (3) large calibre nose-to-retroperitoneum drain insertion; (4) when a wide damage of the jejunal wall or a coexistent biliary-jejunal leak were observed, triple metal stent insertion was performed as follow in order to close the defect: enteral fully-covered SEMS in the jejunal stump, a pancreatic metal stent into the Wirsung duct and a fully-covered SEMS across the bilio-digestive anastomosis, through the meshes of the enteral stent. In all cases, surgical drain was simultaneously retracted. RESULTS: We identified 13 patients who underwent endoscopic treatment for POPF after PD. In total, 5 patients underwent "Yoyo stent insertion", 3 with nose-to-collection drain placement and four patients were treated with triple-stent insertion; in only one patient intrapancreatic SEMS insertion was performed. Technical success was 100% and clinical success was 83.3%. Mean time for leak closure was 4.8 days (range 2-10). During the follow-up interval, no leak recurrences were observed. CONCLUSIONS: Our experience confirms efficacy and safety of endoscopic management of POPF following pancreatoduodenectomy management. Endoscopy should play a central role in this clinical scenario.

A Self-Powered and Battery-Free Vibrational Energy to Time Converter for Wireless Vibration Monitoring.

Wireless sensor nodes (WSNs) are the fundamental part of an Internet of Things (IoT) system for detecting and transmitting data to a master node for processing. Several research studies reveal that one of the disadvantages of conventional, battery-powered WSNs, however, is that they typically require periodic maintenance. This paper aims to contribute to existing research studies on this issue by exploring a new energy-autonomous and battery-free WSN concept for monitor vibrations. The node is self-powered from the conversion of ambient mechanical vibration energy into electrical energy through a piezoelectric transducer implemented with lead-free lithium niobate piezoelectric material to also explore solutions that go towards a greener and more sustainable IoT. Instead of implementing any particular sensors, the vibration measurement system exploits the proportionality between the mechanical power generated by a piezoelectric transducer and the time taken to store it as electrical energy in a capacitor. This helps reduce the component count with respect to conventional WSNs, as well as energy consumption and production costs, while optimizing the overall node size and weight. The readout is therefore a function of the time it takes for the energy storage capacitor to charge between two constant voltage levels. The result of this work is a system that includes a specially designed lead-free piezoelectric vibrational transducer and a battery-less sensor platform with Bluetooth low energy (BLE) connectivity. The system can harvest energy in the acceleration range [0.5 g-1.2 g] and measure vibrations with a limit of detection (LoD) of 0.6 g.

Biomolecular Evaluation of Piceatannol's Effects in Counteracting the Senescence of Mesenchymal Stromal Cells: A New Candidate for Senotherapeutics?

Several investigations on senescence and its causative role in aging have underscored the importance of developing senotherapeutics, a field focused on killing senescent cells and/or preventing their accumulation within tissues. Using polyphenols in counteracting senescence may facilitate the development of senotherapeutics given their presence in the human diet, their confirmed tolerability and absence of severe side effects, and their role in preventing senescence and inducing the death of senescent cells. Against that background, we evaluated the effect of piceatannol, a natural polyphenol, on the senescence of mesenchymal stromal cells (MSCs), which play a key role in the body's homeostasis. Among our results, piceatannol reduced the number of senescent cells both after genotoxic stress that induced acute senescence and in senescent replicative cultures. Such senotherapeutics activity, moreover, promoted the recovery of cell proliferation and the stemness properties of MSCs. Altogether, our findings demonstrate piceatannol's effectiveness in counteracting senescence by targeting its associated pathways and detecting and affecting P53-dependent and P53-independent senescence. Our study thus suggests that, given piceatannol's various mechanisms to accomplish its pleiotropic activities, it may be able to counteract any senescent phenotypes.

Green Deep Eutectic Solvents for Microwave-Assisted Biomass Delignification and Valorisation.

Aiming to fulfil the sustainability criteria of future biorefineries, a novel biomass pretreatment combining natural deep eutectic solvents (NaDESs) and microwave (MW) technology was developed. Results showed that NaDESs have a high potential as green solvents for lignin fractionation/recovery and sugar release in the following enzymatic hydrolysis. A new class of lignin derived NaDESs (LigDESs) was also investigated, showing promising effects in wheat straw delignification. MW irradiation enabled a fast pretreatment under mild condition (120 °C, 30 min). To better understand the interaction of MW with these green solvents, the dielectric properties of NaDESs were investigated. Furthermore, a NaDES using the lignin recovered from biomass pretreatment as hydrogen bond donor was prepared, thus paving the way for a "closed-loop" biorefinery process.

Spatial modes for transmission of chikungunya virus during a large chikungunya outbreak in Italy: a modeling analysis.

BACKGROUND: The spatial spread of many mosquito-borne diseases occurs by focal spread at the scale of a few hundred meters and over longer distances due to human mobility. The relative contributions of different spatial scales for transmission of chikungunya virus require definition to improve outbreak vector control recommendations. METHODS: We analyzed data from a large chikungunya outbreak mediated by the mosquito Aedes albopictus in the Lazio region, Italy, consisting of 414 reported human cases between June and November 2017. Using dates of symptom onset, geographic coordinates of residence, and information from epidemiological questionnaires, we reconstructed transmission chains related to that outbreak. RESULTS: Focal spread (within 1 km) accounted for 54.9% of all cases, 15.8% were transmitted at a local scale (1-15 km) and the remaining 29.3% were exported from the main areas of chikungunya circulation in Lazio to longer distances such as Rome and other geographical areas. Seventy percent of focal infections (corresponding to 38% of the total 414 cases) were transmitted within a distance of 200 m (the buffer distance adopted by the national guidelines for insecticide spraying). Two main epidemic clusters were identified, with a radius expanding at a rate of 300-600 m per month. The majority of exported cases resulted in either sporadic or no further transmission in the region. CONCLUSIONS: Evidence suggest that human mobility contributes to seeding a relevant number of secondary cases and new foci of transmission over several kilometers. Reactive vector control based on current guidelines might allow a significant number of secondary clusters in untreated areas, especially if the outbreak is not detected early. Existing policies and guidelines for control during outbreaks should recommend the prioritization of preventive measures in neighboring territories with known mobility flows to the main areas of transmission.

Effectiveness of Ultra-Low Volume insecticide spraying to prevent dengue in a non-endemic metropolitan area of Brazil.

Management of vector population is a commonly used method for mitigating transmission of mosquito-borne infections, but quantitative information on its practical public health impact is scarce. We study the effectiveness of Ultra-Low Volume (ULV) insecticide spraying in public spaces for preventing secondary dengue virus (DENV) cases in Porto Alegre, a non-endemic metropolitan area in Brazil. We developed a stochastic transmission model based on detailed entomological, epidemiological and population data, accounting for the geographical distribution of mosquitoes and humans in the study area and spatial transmission dynamics. The model was calibrated against the distribution of DENV cluster sizes previously estimated from the same geographical setting. We estimated a ULV-induced mortality of 40% for mosquitoes and found that the implemented control protocol avoided about 24% of symptomatic cases occurred in the area throughout the 2015-2016 epidemic season. Increasing the radius of treatment or the mortality of mosquitoes by treating gardens and/or indoor premises would greatly improve the result of control, but trade-offs with respect to increased efforts need to be carefully analyzed. We found a moderate effectiveness for ULV-spraying in public areas, mainly due to the limited ability of this strategy in effectively controlling the vector population. These results can be used to support the design of control strategies in low-incidence, non-endemic settings.

Advanced Monitoring Systems Based on Battery-Less Asset Tracking Modules Energized through RF Wireless Power Transfer.

Asset tracking involving accurate location and transportation data is highly suited to wireless sensor networks (WSNs) featuring battery-less nodes that can be deployed in virtually any environment and require little or no maintenance. In response to the growing demand for advanced battery-less sensor tag solutions, this article presents a system for identifying and monitoring the speeds of assets in a WSN with battery-less tags that receive all their operating energy through radio frequency (RF) wireless power transfer (WPT) architecture, and a unique measurement approach to generate time-domain speed readouts. The assessment includes performance characteristics and key features of a system on chip (SoC) purposely designed to power a node through RF WPT. The result is an innovative solution for RF to DC conversion able to address the principal difficulties associated with maximum power conversion efficiency (PCE) with sensitivity and vice versa, a strategy, and a design optimization model to indicate the number of readers required for reliable asset identification and speed measurement. Model validation is performed through specific tests. Experimental results demonstrating the viability of the proposed advanced monitoring system are provided.

Spreading depolarizations trigger caveolin-1-dependent endothelial transcytosis.

OBJECTIVE: Cortical spreading depolarizations (CSDs) are intense and ubiquitous depolarization waves relevant for the pathophysiology of migraine and brain injury. CSDs disrupt the blood-brain barrier (BBB), but the mechanisms are unknown. METHODS: A total of six CSDs were evoked over 1 hour by topical application of 300 mM of KCl or optogenetically with 470 nm (blue) LED over the right hemisphere in anesthetized mice (C57BL/6 J wild type, Thy1-ChR2-YFP line 18, and cav-1-/- ). BBB disruption was assessed by Evans blue (2% EB, 3 ml/kg, intra-arterial) or dextran (200 mg/kg, fluorescein, 70,000 MW, intra-arterial) extravasation in parietotemporal cortex at 3 to 24 hours after CSD. Endothelial cell ultrastructure was examined using transmission electron microscopy 0 to 24 hours after the same CSD protocol in order to assess vesicular trafficking, endothelial tight junctions, and pericyte integrity. Mice were treated with vehicle, isoform nonselective rho-associated kinase (ROCK) inhibitor fasudil (10 mg/kg, intraperitoneally 30 minutes before CSD), or ROCK-2 selective inhibitor KD025 (200 mg/kg, per oral twice-daily for 5 doses before CSD). RESULTS: We show that CSD-induced BBB opening to water and large molecules is mediated by increased endothelial transcytosis starting between 3 and 6 hours and lasting approximately 24 hours. Endothelial tight junctions, pericytes, and basement membrane remain preserved after CSDs. Moreover, we show that CSD-induced BBB disruption is exclusively caveolin-1-dependent and requires rho-kinase 2 activity. Importantly, hyperoxia failed to prevent CSD-induced BBB breakdown, suggesting that the latter is independent of tissue hypoxia. INTERPRETATION: Our data elucidate the mechanisms by which CSDs lead to transient BBB disruption, with diagnostic and therapeutic implications for migraine and brain injury.

Concise Review: The Effect of Low-Dose Ionizing Radiation on Stem Cell Biology: A Contribution to Radiation Risk.

Exposure to high levels of ionizing radiation (IR) (>0.5 Gy) negatively affects health, but less is known about the effects of low-dose ionizing radiation (LDIR). Recent evidence suggests that it may have profound effects on cellular functions. People are commonly exposed to LDIR over natural background levels from numerous sources, including LDIR from medical diagnosis and therapy, air travel, illegal IR waste dumpsites, and occupational exposures in the nuclear and medical sectors. Stem cells reside for long periods of time in our bodies, and this increases the possibility that they may accumulate genotoxic damage derived from extrinsic LDIR or intrinsic sources (such as DNA replication). In this review, we provide an overview of LDIR effects on the biology of stem cell compartments. The principal findings and issues reported in the scientific literature are discussed in order to present the current understanding of the LDIR exposure risk and assess whether it may impact human health. We first consider the general biological consequences of LDIR exposure. Following this, we discuss the effects of LDIR on stem cells as discovered through in vitro and in vivo studies. Stem Cells 2018;36:1146-1153.

Endo-therapies for biliary duct-to-duct anastomotic stricture after liver transplantation: Outcomes of a nationwide survey.

BACKGROUND: The most appropriate endo-therapeutic approach to biliary anastomotic strictures is yet to be defined. AIM: To retrospectively report on the endo-therapy of duct-to-duct anastomotic strictures during 2013 in Italy. METHODS: Data were collected from 16 Endoscopy Units at the Italian Liver Transplantation Centers (BASALT study group). RESULTS: Complete endo-therapy and follow-up data are available for 181 patients: 101 treated with plastic multistenting, 26 with fully covered self-expandable metal stenting and 54 with single stenting. Radiological success was achieved for 145 patients (80%), that is, 88% of plastic multistenting, 88% of self-expandable metal stenting and 61% of single stenting (P < 0.001 vs plastic multistenting; P < 0.05 vs self-expandable metal stenting). After first-line endo-therapy failure, the patients underwent a second-line endo-therapy with plastic multistenting for 25%, fully covered self-expandable metal stenting for 53% and single stenting for 22% of cases, and radiological success was achieved for 84%, that is, 100%, 85% and 63% with plastic multistenting, self-expandable metal stenting and single stenting (P < 0.05 vs plastic multistenting or self-expandable metal stenting) respectively. Procedure-related complications occurred in 7.8% of endoscopic retrograde cholangiopancreatographies. Overall, clinical success was achieved in 87% of patients after a median follow-up of 25 months. CONCLUSION: Plastic multistenting is confirmed as the preferred first-line treatment, while fully covered self-expandable metal stenting as rescue option for biliary anastomotic strictures. Single stenting has sub-optimal results and should be abandoned.

A multi-center analysis of readmission after cardiac surgery: Experience of The Northern New England Cardiovascular Disease Study Group.

BACKGROUND: Readmissions after cardiac surgery are common and associated with increased morbidity, mortality and cost of care. Policymakers have targeted coronary artery bypass grafting to achieve value-oriented health care milestones. We explored the causes of readmission following cardiac surgery among a regional consortium of hospitals. METHODS: Using administrative data, we identified patients readmitted to the same institution within 30 days of cardiac surgery. We performed standardized review of readmitted patients' medical records to identify primary and secondary causes of readmission. We evaluated causes of readmission by procedure and tested for univariate associations between characteristics of readmitted patients and nonreadmitted patients in our clinical registry. RESULTS: Of 2218 cardiac surgery patients, 272 were readmitted to the index hospital within 30 days for a readmission rate of 12.3%. Median time to readmission was 9 days (interquartile range 4-16 days) and only 13% of patients were evaluated in-office before readmission. Readmitted patients were more likely to have had valve surgery (31.3% vs 22.7%) than patients not readmitted. Readmitted patients were also more likely to have preoperative creatinine more than or equal to 2 mg/dL (P = .015) or congestive heart failure (CHF) (P = .034), require multiple blood transfusions or sustained inotropic support (P < .001), and experience postoperative atrial fibrillation (P = .022) or renal insufficiency (P < .001). Infection (26%), pleural or pericardial effusion (19%), arrhythmia (16%), and CHF (11%) were the most common primary etiologies leading to readmission. CONCLUSIONS: Ensuring early follow-up for high-risk patient groups while improving early detection and management of the principal drivers of readmission represent promising targets for decreasing readmission rates.

Strategies and Techniques for Powering Wireless Sensor Nodes through Energy Harvesting and Wireless Power Transfer.

The continuous development of internet of things (IoT) infrastructure and applications is paving the way for advanced and innovative ideas and solutions, some of which are pushing the limits of state-of-the-art technology. The increasing demand for Wireless Sensor Nodes (WSNs) able to collect and transmit data through wireless communication channels, while often positioned in locations that are difficult to access, is driving research into innovative solutions involving energy harvesting (EH) and wireless power transfer (WPT) to eventually allow battery-free sensor nodes. Due to the pervasiveness of radio frequency (RF) energy, RF EH and WPT are key technologies with the potential to power IoT devices and smart sensing architectures involving nodes that need to be wireless, maintenance free, and sufficiently low in cost to promote their use almost anywhere. This paper presents a state-of-the-art, ultra-low power 2.5 µ W highly integrated mixed signal system on chip (SoC), for multi-source energy harvesting and wireless power transfer. It introduces a novel architecture that integrates an ultra-low power intelligent power management, an RF to DC converter with very low power sensitivity and high power conversion efficiency (PCE), an Amplitude-Shift-Keying/Frequency-Shift-Keying (ASK/FSK) receiver and digital circuitry to achieve the advantage to cope, in a versatile way and with minimal use of external components, with the wide variety of energy sources and use cases. Diverse methods for powering Wireless Sensor Nodes through energy harvesting and wireless power transfer are implemented providing related system architectures and experimental results.

Irradiation of Mesenchymal Stromal Cells With Low and High Doses of Alpha Particles Induces Senescence and/or Apoptosis.

The use of high-linear energy transfer charged particles is gaining attention as a medical tool because of the emission of radiations with an efficient cell-killing ability. Considerable interest has developed in the use of targeted alpha-particle therapy for the treatment of micrometastases. Moreover, the use of helium beams is gaining momentum, especially for treating pediatric tumors. We analyzed the effects of alpha particles on bone marrow mesenchymal stromal cells (MSCs), which have a subpopulation of stem cells capable of generating adipocytes, chondrocytes, and osteocytes. Further, these cells contribute toward maintenance of homeostasis in the body. MSCs were irradiated with low and high doses of alpha particles or X-rays and a comparative biological analysis was performed. At a low dose (40 mGy), alpha particles exhibited a limited negative effect on the biology of MSCs compared with X-rays. No significant perturbation of cell cycle was observed, and a minimal increase in apoptosis or senescence was detected. Self-renewal was preserved as revealed by the CFU assay. On the contrary, with 2000 mGy alpha particles, we observed adverse effects on the vitality, functionality, and stemness of MSCs. These results are the consequence of different proportion of cells targeted by alpha particles or X-rays and the quality of induced DNA damage. The present study suggests that radiotherapy with alpha particles may spare healthy stem cells more efficaciously than X-ray treatments, an observation that should be taken into consideration by physicians while planning irradiation of tumor areas close to stem cell niches, such as bone marrow. J. Cell. Biochem. 118: 2993-3002, 2017. © 2017 Wiley Periodicals, Inc.

Point shear-wave elastography in chronic pancreatitis: A promising tool for staging disease severity.

BACKGROUND: Objectives: ElastPQ®-pSWE is an ultrasound technique developed to stage disease severity in patients with chronic liver diseases. Little data is available about its application to the pancreas. We aimed to assess the feasibility and reproducibility of pancreatic stiffness (PS) measurements in patients with chronic pancreatitis and their relationship with clinical and laboratory data. MATERIAL AND METHODS: 52 consecutive patients with chronic pancreatitis (CP) (40 males; median age 60 years) underwent hepatic and pancreatic pSWE. Liver stiffness was measured by transient elastography, 42 healthy subjects being controls (25 males; median age 54 years). Pancreatic pSWE inter-observer agreement was analyzed by intraclass correlation coefficient (ICC). The effects of clinical, laboratory and US data on PS measurements were evaluated by linear regression. RESULTS: pSWE was feasible in all the CP patients, but one. Pancreatic stiffness was significantly higher in CP patients than healthy controls (4.3 ± SD 2.4 vs. 2.8 ± SD 1.1 kPa, respectively, p = 0.001). Significantly higher values in the CP group were observed in patients with longer disease duration (>10 vs. ≤10 years) (5.8 ± SD 4 vs. 3.9 ± SD 1.5 kPa, respectively, p = 0.01), on chronic analgesic drugs (6.0 vs. 3.5 kPa, p < 0.05) and with lower body weight (p < 0.05, r = -0.38). At multivariate analysis all the three variables resulted independently associated to the pancreatic stiffness value. The ICC for PS was 0.77. CONCLUSIONS: ElastPQ®-pSWE is promising and reproducible in assessing pancreatic stiffness, which mainly reflects disease length and severity. Accordingly, its use is of potential value in stratifying CP patients by identifying those with a more serious degree of disease.

Exploring vector-borne infection ecology in multi-host communities: A case study of West Nile virus.

In this study, we develop a model to investigate how ecological factors might affect the dynamics of a vector-borne pathogen in a population composed by different hosts which interact with each other. Specifically, we consider the case when different host species compete with each other, as they share the same habitat, and the vector might have different feeding preference, which can also be time dependent. As a prototypical example, we apply our model to study the invasion and spread, during a typical season, of West Nile virus in an ecosystem composed of two competent avian host species and possibly of dead-end host species. We found that competition and vector feeding preferences can profoundly influence pathogen invasion, influencing its probability to start an epidemic, and influencing transmission rates. Finally, when considering time-dependent feeding preferences, as observed in the field, we noted that the virus circulation could be amplified and that the timing of epidemic peaks could be changed. Our work highlights that ecological interactions between hosts can have a profound influence on the dynamics of the pathogen and that, when modeling vector-borne infections, vector feeding behavior should, for this reason, be carefully evaluated.