Trifurcated Splitting of Water Droplets on Engineered Lithium Niobate Surfaces

Controlled splitting of liquid droplets is a key function in many microfluidic applications. In recent years, various methodologies have been used to accomplish this task. Here, we present an optofluidic technique based on an engineered surface formed by coating a z-cut iron-doped lithium niobate crystal with a lubricant-infused layer, which provides a very slippery surface. Illuminating the crystal with a light spot induces surface charges of opposite signs on the two crystal faces because of the photovoltaic effect. If the light spot is sufficiently intense, millimetric water droplets placed near the illuminated spot split into two charged fragments, one fragment being trapped by the bright spot and the other moving away from it. The latter fragment does not move randomly but rather follows one of three well-defined trajectories separated by 120°, which reflect the anisotropic crystalline structure of Fe:LiNbO3. Numerical simulations explain the behavior of water droplets in the framework of the forces induced by the interplay of pyroelectric, piezoelectric, and photovoltaic effects, which originate simultaneously inside the illuminated crystal. Such a synergetic effect can provide a valuable feature in applications that require splitting and coalescence of droplets, such as chemical microreactors and biological encapsulation and screening.

Shaking Device for Homogeneous Dispersion of Magnetic Beads in Droplet Microfluidics

Magnetic beads (or particles) having a size between 1 and 5 µm are largely used in many biochemical assays devoted to both purification and quantification of cells, nucleic acids, or proteins. Unfortunately, the use of these beads within microfluidic devices suffers from natural precipitation because of their size and density. The strategies applied thus far to cells or polymeric particles cannot be extended to magnetic beads, mainly due to their magnetization and their higher densities. We report an effective shaking device capable of preventing the sedimentation of beads that are stored in a custom PCR tube. After the characterization of the operating principle, the device is validated for magnetic beads in droplets, leading to an equal distribution between the droplets, barely affecting their generation.

Sliding and rolling of yield stress fluid droplets on highly slippery lubricated surfaces

HYPOTHESIS

Droplets of yield stress fluids (YSFs), i.e. fluids that can flow only if they are subjected to a stress above a critical value and otherwise deform like solids, hardly move on solid surfaces due to their high viscosity. The use of highly slippery lubricated surfaces can shed light on the mobility of YSF droplets, which include everyday soft materials, such as toothpaste or mayonnaise, and biological fluids, such as mucus.

EXPERIMENTS

The spreading and mobility of droplets of aqueous solutions of swollen Carbopol microgels were studied on lubricant infused surfaces. These solutions represent a model system of YSFs. Dynamical phase diagrams were established by varying the concentration of the solutions and the inclination angle of the surfaces.

FINDINGS

Carbopol droplets deposited on lubricated surfaces could move even at low inclination angles. The droplets were found to slide because of the slip of the flowing oil that covered the solid substrate. However, as the descending speed increased, the droplets rolled down. Rolling was favored at high inclinations and low concentrations. A simple criterion based on the ratio between the yield stress of the Carbopol suspensions and the gravitational stress acting on the Carbopol droplets was found to nicely identify the transition between the two regimes.

Microfluidic Strategies for Extracellular Vesicle Isolation: Towards Clinical Applications

Extracellular vesicles (EVs) are double-layered lipid membrane vesicles released by cells. Currently, EVs are attracting a lot of attention in the biological and medical fields due to their role as natural carriers of proteins, lipids, and nucleic acids. Thus, they can transport useful genomic information from their parental cell through body fluids, promoting cell-to-cell communication even between different organs. Due to their functionality as cargo carriers and their protein expression, they can play an important role as possible diagnostic and prognostic biomarkers in various types of diseases, e.g., cancers, neurodegenerative, and autoimmune diseases. Today, given the invaluable importance of EVs, there are some pivotal challenges to overcome in terms of their isolation. Conventional methods have some limitations: they are influenced by the starting sample, might present low throughput and low purity, and sometimes a lack of reproducibility, being operator dependent. During the past few years, several microfluidic approaches have been proposed to address these issues. In this review, we summarize the most important microfluidic-based devices for EV isolation, highlighting their advantages and disadvantages compared to existing technology, as well as the current state of the art from the perspective of the use of these devices in clinical applications.

Is there an association between Stevens-Johnson Syndrome and vaccination? A systematic review

AIMS AND BACKGROUND

It is essential to make sure that vaccines are safe, effective, and of good quality. In the past years, there have been some reports of adverse effects regarding vaccination. One of these adverse effects is the development of Stevens-Johnson syndrome. Stevens-Johnson syndrome is a rare, severe, skin disorder, that usually occurs after medication. In Europe, its estimated incidence is of 2-3 cases/million population/year. Therefore, the aim of this study was to investigate, through a systematic review, the association between vaccination and the development of Stevens-Johnson syndrome.

MATERIALS AND METHODS

We performed a systematic review using PubMed, Scopus and Web of Science databases. We included studies dated between January 2000 and February 2018. The main selection criterion was the reporting of the disease, following vaccination.

RESULTS

Ten studies were selected, from a total of 391 studies. Of these, 5 were case reports, 3 were cohort studies and 2 were case-control. All the studies were regarding cases of Stevens-Johnson syndrome after vaccination. The selected studies reported cases following vaccines such as influenza vaccine, smallpox, anthrax and tetanus vaccine, MMR vaccine, varicella vaccine, DTaP-IPV vaccine or rabies vaccine. None of the cohort studies reported statistically significant associations between vaccination and the syndrome. In the case-control studies, it was not observed significant increased risk for the Stevens-Johnson syndrome following the administration of vaccines. Regarding the case reports, there was not sufficient evidence to form a positive association between these two factors, and more studies are needed.

CONCLUSIONS

In this review it was not possible to establish a positive relation between vaccination and the development of Stevens-Johnson syndrome.

The case of Patient Safety Indicator 12 (PSI12): use of administrative data to estimate the incidence of "Postoperative Pulmonary Embolism or Deep Vein Thrombosis". A pilot study in a General Hospital

INTRODUCTION

The AHRQ Quality Indicators (QIs) were created in order to both identify the performance and to track the improvement of patient safety. Patient Safety Indicator 12 (PSI12) is relative to the risk of Post Operatory Pulmonary Embolism or Deep Venous Thrombosis (PO DVT/PE). This pilot study has three main objectives. Firstly, to perform an analysis of the performance of different hospital wards by using administrative data; secondly, to analyze defects in the process that led to the occurrence of the adverse event; thirdly, reviewing the single PO DVT/PE.

METHODS

Data were extracted from a Hospital Information data flow (SIO) and compared to Clinical Discharge Record. PSI12 estimates were computed before and after the screening. Control Charts allowed the static analysis of performance between different hospital wards in 2014. The Ishikawa diagram was drawn for the analysis of the underlying causal process.

RESULTS

The number of PSI12 cases provided by DRGs through SIO data flow decreased from 45 to six after the comparison with the correspondent clinical records. Four clinical records provided full information allowing the analysis of process. The Ishikawa Diagram identified the defects in the process of prophylaxis that resulted into a PO DVT/PE.

DISCUSSIONS

The clinical records screening revealed a lower incidence of PO DVT/PE with respect to the DRGs statistics. Overall the PO DVT/PE occurrence in 2014 fell into the control limits, although the result could be undermined by the low quality of clinical records compilation. The failure in the prophylaxis procedure was imputable to pitfalls in the health care management and to the individual attitude towards patient safety procedures. In conclusion, the reliability and validity of administrative data in monitoring quality and safety are worthy to be explored in the context of further validation studies.

Errors in Medicine: perception of healthcare professionals in the Lazio Region

INTRODUCTION

The error in medicine is always the subject of debate in the scientific debates. The purpose of this study is to evaluate the degree knowledge, attitudes and behaviors of health workers towards the error in the health sector.

METHODS

A survey was carried out involving 435 health profes- sionals working in health facilities of the Lazio region, of which 312 females (71%) and 123 males (28%) with an age between 21 and 68 years. A structured questionnaire was administered for investigating the experiences and opinions about the errors found in medical prac- tice, the causes underlying them and the mistakes that should never be committed. Data were collected, stratified by sex, age, marital status, year of graduation, years of service and the workplace (medical or surgical). The statistical significance was set at p≤0.05.

RESULTS

The 5 errors found more frequently in the clinical prac- tice by health professionals were as follows: errors related to the request for examination (60.9%); errors in the collection of samples (37.5%); errors relating to the delivery of the reports (35.2%); errors due to reporting of examinations (31.7%); errors of history (29.2%). The five cases considered to be the most frequently responsible for such errors were: disorganization (52%); fast (46.4%); tiredness due to excessive workloads, stress (44.6%); negligence and carelessness (41.6%); inattention (41.1). With regard to the errors that you should never commit they were more frequently: exchange of patient or misidentification of the patient (49.2%); administration errors of therapies or medications (47.6%); errors related to surgery (41.6%); errors of prescription therapies or medications (39.3); errors in the reporting of exams (33.6%).

CONCLUSIONS

The results of this study shows the importance of a culture of error in medicine among healthcare professionals, those who have already gained practical experience in health care and therefore better able to perform a critical analysis and evaluation of the errors that occur every day. The continuous training of health professionals is fundamental for promoting patient safety and quality in the healthcare sector.

The role of Pap test screening against cervical cancer: a systematic review and meta-analysis

OBJECTIVE

The first aim of this article is to quantify the role of Pap test in cervical cancer prevention, updating the pool of available studies included in a previous meta-analysis. Potential sources of meta-analysis heterogeneity were investigated as second aim. Further evidence of cost-effectiveness has been provided about age and best time interval to perform Pap test screening.

DATA SOURCES

The articles' search was conducted using four medical electronic databases: PubMed, Google Scholar, ISI Web, and Scopus. Papers published until the 30th November 2013 were included. The research on Google Scholar was limited to the first 10 pages of web for each study design.

METOD OF STUDY SELECTION

A systematic review/meta-analysis was performed according to PRISMA Statement. New-Castle-Ottawa Scale and Jadad have been adopted for articles quality assessment. From 4143 screened articles, 34 met eligibility criteria and 30 case-control studies were included in meta-analysis. Meta-analysis was carried out using StatsDirect2.8.0. Heterogeneity was investigated with qualitative and quantitative approaches in sensitivity-analysis.

TABULATION, INTEGRATION AND RESULTS

Despite a great heterogeneity (Cochran Q=504.466, df=29, p<0.0001; I²=94.3%; 95%CI=93.1%-95.1%), a significant protective effect of Pap test has been identified (OR=0.33; 95%CI=0.268-0.408, P <0.00011) through the meta-analysis. Sensitivity analysis did not provide significant results (R=0.358 R2=0.128 p<0.469).

CONCLUSIONS

The protective role of Pap test against cervical cancer has been confirmed especially among women <40 years. Annual screening still remains the most cost-effective preventive strategy.

Knowledge of Emergency Department Triage nurses in management of patients with mental health needs: comparisons with the Triage Model of Lazio (TLM)

OBJECTIVES

To refer the current competences of Triage Nurses (TRNs) assessing the person with metal health problems in Emergency Departments (ED), and the impact of the Triage Lazio Model (TLM) upon it.

MATERIALS AND METHODS

An anonymous questionnaire was administered to ED TRNs of the Lazio Region. Standardized Cronbach's alpha was used for reliability estimation.

RESULTS

The Cronbach's alpha was 0.4. Two hundred ninety-nine TRNs were interviewed: 66% women, 47% aged 31-40 years, 60% followed TLM. The consideration of the patient as 'one who comes out of the normal', 'a person with altered functions of mind or mental function' and as 'hostile, aggressive and unpredictable' was reported more by females in comparison to the males (OR=1.76; OR=3.50; OR=1.79); TRNs who have not followed the course on TLM had higher probability to consider 'hostile, aggressive and unpredictable' the psychiatric patients (OR=1.87) in comparison with other Triage courses; those who have taken a course on Triage but at least 3 years ago, had a lower probability to consider as 'one who comes out of the normal' (OR=0.55).

CONCLUSIONS

having followed the course TLM, having participated in a recent triage course, male gender, and the seniority in this job appear to be contributing factors for a proper management of psychiatric patients. Continuous improvement of specific knowledge and skills for the management of patients with mental health needs are mandatory.