High-throughput microfluidic platform for adherent single cells non-viral gene delivery

The widespread use of gene therapy as a therapeutic tool relies on the development of DNA-carrying vehicles devoid of any safety concerns. In contrast to viral vectors, non-viral gene carriers show promise in this perspective, although their low transfection efficiency leads to the necessity to carry out further optimizations. In order to overcome the limitations of traditional macroscale approaches, which mainly consist of time-consuming and simplified models, a microfluidic strategy has been developed to carry out transfection studies on single cells in a high-throughput and deterministic fashion. A single cell trapping mechanism has been implemented, based on the dynamic variation of fluidic resistances. For this purpose, we designed a round-shaped culture chamber integrated with a bottom trapping junction, which modulates the hydraulic resistance. Several layouts of the chamber were designed and computationally validated for optimization of the single cell trapping efficacy. The optimized chamber layout was integrated in a polydimethylsiloxane (PDMS) microfluidic platform presenting two main functionalities: (i) 288 chambers for trapping single cells, and (ii) a serial dilution generator with chaotic mixing properties, able to deliver to the chambers both soluble factors and non-diffusive particles (i.e., polymer/DNA complexes, polyplexes) under spatio-temporally controlled chemical patterns. The devices were experimentally validated and allowed the trapping of individual human glioblastoma–astrocytoma epithelial-like cells (U87-MG) with a trapping efficacy of about 40%. The cells were cultured within the device and underwent preliminary transfection experiments using 25 kDa linear polyethylenimine (lPEI)-based polyplexes, confirming the potentiality of the proposed platform for the future high-throughput screening of gene delivery vectors and for the optimization of transfection protocols

Microfluidic Platform for Adherent Single Cell High-Throughput Screening

This paper was presented at the 4th Micro and Nano Flows Conference (MNF2014), which was held at University College, London, UK. The conference was organised by Brunel University and supported by the Italian Union of Thermofluiddynamics, IPEM, the Process Intensification Network, the Institution of Mechanical Engineers, the Heat Transfer Society, HEXAG - the Heat Exchange Action Group, and the Energy Institute, ASME Press, LCN London Centre for Nanotechnology, UCL University College London, UCL Engineering, the International NanoScience Community, www.nanopaprika.eu.Traditionally, in vitro investigations on biology and physiology of cells rely on averaging the responses eliciting from heterogeneous cell populations, thus being unsuitable for assessing individual cell behaviors in response to external stimulations. In the last years, great interest has thus been focused on single cell analysis and screening, which represents a promising tool aiming at pursuing the direct and deterministic control over cause-effect relationships guiding cell behavior. In this regard, a high-throughput microfluidic platform for trapping and culturing adherent single cells was presented. A single cell trapping mechanism was implemented based on dynamic variation of fluidic resistances. A round-shaped culture chamber (Φ=250μm, h=25μm) was conceived presenting two connections with a main fluidic path: (i) an upper wide opening, and (ii) a bottom trapping junction which modulates the hydraulic resistance. Several layouts of the chamber were designed and computationally validated for the optimization of the single cell trapping efficacy. The optimized chamber layouts were integrated in a polydimethylsiloxane (PDMS) microfluidic platform presenting two main functionalities: (i) 288 chambers for trapping single cells, and (ii) a chaoticmixer based serial dilution generator for delivering both soluble factors and non-diffusive molecules under spatio-temporally controlled chemical patterns. The devices were experimentally validated and allowed for trapping individual U87-MG (human glioblastoma-astrocytoma epithelial-like) cells and culturing them up to 3 days

Mapping Asbestos-Cement Roofing with Hyperspectral Remote Sensing over a Large Mountain Region of the Italian Western Alps

The World Health Organization estimates that 100 thousand people in the world die every year from asbestos-related cancers and more than 300 thousand European citizens are expected to die from asbestos-related mesothelioma by 2030. Both the European and the Italian legislations have banned the manufacture, importation, processing and distribution in commerce of asbestos-containing products and have recommended action plans for the safe removal of asbestos from public and private buildings. This paper describes the quantitative mapping of asbestos-cement covers over a large mountainous region of Italian Western Alps using the Multispectral Infrared and Visible Imaging Spectrometer sensor. A very large data set made up of 61 airborne transect strips covering 3263 km2 were processed to support the identification of buildings with asbestos-cement roofing, promoted by the Valle d’Aosta Autonomous Region with the support of the Regional Environmental Protection Agency. Results showed an overall mapping accuracy of 80%, in terms of asbestos-cement surface detected. The influence of topography on the classification’s accuracy suggested that even in high relief landscapes, the spatial resolution of data is the major source of errors and the smaller asbestos-cement covers were not detected or misclassified

In vitro and in vivo evaluation of a new active heat moisture exchanger.

INTRODUCTION: In order to improve the efficiency of heat moisture exchangers (HMEs), new hybrid humidifiers (active HMEs) that add water and heat to HMEs have been developed. In this study we evaluated the efficiency, both in vitro and in vivo, of a new active HME (the Performer; StarMed, Mirandola, Italy) as compared with that of existing HMEs (Hygroster and Hygrobac; Mallinckrodt, Mirandola, Italy). METHODS: We tested the efficiency by measuring the temperature and absolute humidity (AH) in vitro using a test lung ventilated at three levels of minute ventilation (5, 10 and 15 l/min) and at two tidal volumes (0.5 and 1 l), and in vivo in 42 patients with acute lung injury (arterial oxygen tension/fractional inspired oxygen ratio 283 +/- 72 mmHg). We also evaluated the efficiency in vivo after 12 hours. RESULTS: In vitro, passive Performer and Hygrobac had higher airway temperature and AH (29.2 +/- 0.7 degrees C and 29.2 +/- 0.5 degrees C, [P < 0.05]; AH: 28.9 +/- 1.6 mgH2O/l and 28.1 +/- 0.8 mgH2O/l, [P < 0.05]) than did Hygroster (airway temperature: 28.1 +/- 0.3 degrees C [P < 0.05]; AH: 27 +/- 1.2 mgH2O/l [P < 0.05]). Both devices suffered a loss of efficiency at the highest minute ventilation and tidal volume, and at the lowest minute ventilation. Active Performer had higher airway temperature and AH (31.9 +/- 0.3 degrees C and 34.3 +/- 0.6 mgH2O/l; [P < 0.05]) than did Hygrobac and Hygroster, and was not influenced by minute ventilation or tidal volume. In vivo, the efficiency of passive Performer was similar to that of Hygrobac but better than Hygroster, whereas Active Performer was better than both. The active Performer exhibited good efficiency when used for up to 12 hours in vivo. CONCLUSION: This study showed that active Performer may provide adequate conditioning of inspired gases, both as a passive and as an active device

Expression of Distal-less, dachshund, and optomotor blind in Neanthes arenaceodentata (Annelida, Nereididae) does not support homology of appendage-forming mechanisms across the Bilateria

The similarity in the genetic regulation of arthropod and vertebrate appendage formation has been interpreted as the product of a plesiomorphic gene network that was primitively involved in bilaterian appendage development and co-opted to build appendages (in modern phyla) that are not historically related as structures. Data from lophotrochozoans are needed to clarify the pervasiveness of plesiomorphic appendage forming mechanisms. We assayed the expression of three arthropod and vertebrate limb gene orthologs, Distal-less (Dll), dachshund (dac), and optomotor blind (omb), in direct-developing juveniles of the polychaete Neanthes arenaceodentata. Parapodial Dll expression marks premorphogenetic notopodia and neuropodia, becoming restricted to the bases of notopodial cirri and to ventral portions of neuropodia. In outgrowing cephalic appendages, Dll activity is primarily restricted to proximal domains. Dll expression is also prominent in the brain. dac expression occurs in the brain, nerve cord ganglia, a pair of pharyngeal ganglia, presumed interneurons linking a pair of segmental nerves, and in newly differentiating mesoderm. Domains of omb expression include the brain, nerve cord ganglia, one pair of anterior cirri, presumed precursors of dorsal musculature, and the same pharyngeal ganglia and presumed interneurons that express dac. Contrary to their roles in outgrowing arthropod and vertebrate appendages, Dll, dac, and omb lack comparable expression in Neanthes appendages, implying independent evolution of annelid appendage development. We infer that parapodia and arthropodia are not structurally or mechanistically homologous (but their primordia might be), that Dll’s ancestral bilaterian function was in sensory and central nervous system differentiation, and that locomotory appendages possibly evolved from sensory outgrowths

Spontaneous Preterm Birth Phenotyping Based on Cervical Length and Immune-Mediated Factors

Cervical length (CL) screening by ultrasonographic measurement is an established tool widely implemented in the clinical protocols of preterm birth (PTB) prediction and prevention. Growing evidence has shown immune-mediated factors in the etiology of spontaneous PTB (sPTB), with robust biological plausibility supporting deep interrelationships with progressive cervical shortening. We explore a retrospective cohort study that examined the sequential measurement of CL and leucocyte markers in both singleton and twin pregnancies.1 The study’s objective was to identify the clinical presentations associated with sPTB in relation to variations in these parameters.1 Progressive CL shortening was associated with higher rates of sPTB in both singletons (4.1% vs 2.7%) and twins (41.9% vs 18.2%) as compared with cases with stable CL. In addition, in singleton pregnancies, individuals in the early preterm birth subgroup with a shortened or stable CL had elevated total white blood cell count, neutrophil count, and neutrophil-to-lymphocyte ratio, along with a reduced lymphocyte-to-monocyte ratio, in comparison with individuals in the full-term birth subgroup. However, in twins, similar changes were exclusive to those with a shortened cervix. Finally, the study quantified the association between immune-related indicators and risk of sPTB, incorporating CL. In singleton pregnancies, an increase in the white blood cell count and neutrophil count was associated with early sPTB for both stable and shortened CL. Conversely, in twins, there was a significantly higher white blood cell count, neutrophil count, and monocyte count only in the subgroup with shortened C

How symmetry between intrafirm knowledge and collaboration structures influences exploratory innovation under conditions of combinability

We examine how symmetry between intrafirm knowledge and collaboration structures influences firms' exploratory innovation performance. Symmetry means that the inventors' collaboration structure mimics their knowledge structure, implying that inventors with similar domain knowledge collaborate, whereas inventors with dissimilar domain knowledge do not. We argue and show that intrafirm symmetry is the commonly used form by most firms, as it is intuitive and pays off on average. However, it also comes with an inherent risk for their exploratory innovation performance. To address this, we include a key condition of a firm's technological environment: the ease or difficulty with which its knowledge domains can be combined. Based on a sample of 170 publicly traded semiconductor firms over 23 years, we find a positive association between the symmetry of a firm's collaboration and knowledge structure and its exploratory innovation performance under average combinability. This relationship changes when firms operate under low or high combinability conditions. Both these conditions favor firms that deviate from symmetry by relying on a parallel, isolated configuration or multidisciplinary configuration. Our contribution to the literature lies herein that we show when firms and their managers should pay attention to stimulating and optimizing collaboration, as has been the dominant focus until now, but also, and equally important, when disbanding this standing collaboration among inventors is more effective for a firm's exploratory innovation. Most firms overlook the risk that comes with a symmetric configuration under conditions of low or high combinability and are better off instead through one of two less common, asymmetric configurations of their inventor collaboration and knowledge structures.<br/

Reference ranges of uterine artery pulsatility index from first to third trimester based on serial Doppler measurements: longitudinal cohort study

Objective: To provide gestational-age (GA)-specific reference ranges for mean uterine artery (UtA) pulsatility index (PI) based on longitudinal data assessment throughout pregnancy. Methods: This was a prospective longitudinal cohort study of singleton low-risk pregnancies with adequate health and nutritional status at the time of enrolment and without fetal anomaly, receiving prenatal care between January 2018 and July 2021 at the Maternal Fetal Medicine Unit of IRCCS San Raffaele Scientific Institute, Milan, Italy. Women were recruited at ≤ 12 + 6 weeks' gestation and underwent serial standardized ultrasound monitoring, including UtA-PI measurement, by experienced certified operators until delivery. Association of UtA-PI with GA was modeled with fractional polynomial regression. Equations for mean ± SD of the estimated curves were calculated, as well as GA-specific reference charts of centiles for UtA-PI from 10 + 0 to 39 + 0 gestational weeks. Results: We included 476 healthy, low-risk pregnant women and a total of 2045 ultrasound scans (median, 4 (range, 3–9) per patient) were available for analysis. Mean UtA-PI was 1.84 ± 0.55, 1.07 ± 0.38 and 0.78 ± 0.23 in the first, second and third trimesters of pregnancy, respectively. Goodness-of-fit assessment revealed that second-degree smoothing was the most accurate fractional polynomial for describing the course of UtA-PI throughout gestation; therefore, it was modeled in a multilevel framework for the construction of UtA-PI curves. We observed a rapid and substantial decrease in mean UtA-PI before 16 weeks, with subsequent smoother decrement of the slope and more stable values from 20 until 39 weeks. The 3rd, 5th, 10th, 25th, 50th, 75th, 90th, 95th and 97th centiles according to GA for UtA-PI are provided, as well as equations to allow calculation of any value as a centile. Conclusions: UtA-PI shows a progressive non-linear decrease throughout pregnancy. The new reference ranges for GA-specific mean UtA-PI constructed using rigorous methodology may have a better performance compared with previous models for screening for placenta-associated diseases in the early stages of pregnancy and for evaluating the potential risk for pregnancy-induced hypertension and/or small-for-gestational age later in pregnancy

Maternal prepregnancy weight as an independent risk factor for congenital heart defect: systematic review and meta‐analysis stratified by subtype and severity of defect

Objective: To assess the association between increased maternal prepregnancy body mass index (BMI) and the risk of congenital heart defect (CHD) in offspring. Methods: This systematic review and meta-analysis searched PubMed/MEDLINE, Web of Science and Scopus from inception to 20 April 2023. Risk estimates were abstracted or calculated for increased BMI categories (overweight, obesity, moderate obesity and severe obesity) compared with normal weight (reference). Fixed-effects or random-effects models were used to combine individual study risk estimates based on the degree of heterogeneity. Sensitivity analyses were conducted to weight pooled estimates for relevant moderators, particularly diabetes before and during pregnancy. Subgroup analyses for specific CHD subtypes were conducted if there were at least two studies with available data. Findings were presented for groups of defects, categorized using severity and topographic–functional criteria, and for individual defects. The certainty of the evidence for each effect estimate was evaluated according to Grading of Recommendations, Assessment, Development and Evaluation (GRADE) guidelines. Results: Overall, 31 studies comprising 4 861 693 patients and 86 136 CHD cases were included. The risk of CHD increased progressively from moderate to severe obesity (pooled odds ratio (OR), 1.15 (95% CI, 1.11–1.20) and 1.39 (95% CI, 1.27–1.53), respectively). Sensitivity analysis indicated that this effect persisted independently of maternal diabetes status before or during pregnancy. In the subgroup analysis, obesity was associated with up to a 1.5-fold increase in the risk of severe CHD (pooled OR, 1.48 (95% CI, 1.03–2.13)). Severe obesity was associated with an even higher risk, with 1.8-times higher odds compared with the reference group for specific CHD subtypes, including tetralogy of Fallot (pooled OR, 1.72 (95% CI, 1.38–2.16)), pulmonary valve stenosis (pooled OR, 1.79 (95% CI, 1.39–2.30)) and atrial septal defect (pooled OR, 1.71 (95% CI, 1.48–1.97)). Conclusions: Maternal weight is a crucial modifiable risk factor for CHD, particularly for severe forms of defect. Further research is needed to investigate whether weight management before pregnancy might serve as a preventive measure against CHD. In pregnant women with obesity, fetal echocardiography should be a routine diagnostic procedure

Time to redefine endometriosis including its pro-fibrotic nature

Endometriosis is currently defined as presence of endometrial epithelial and stromal cells at ectopic sites. This simple and straightforward definition has served us well since its original introduction. However, with advances in disease knowledge, endometrial stromal and glands have been shown to represent only a minor component of endometriotic lesions and they are often absent in some disease forms. In rectovaginal nodules, the glandular epithelium is often not surrounded by stroma and frequently no epithelium can be identified in the wall of ovarian endometriomas. On the other hand, a smooth muscle component and fibrosis represent consistent features of all disease forms. Based on these observations, we believe that the definition of endometriosis should be reconsidered and reworded as 'A fibrotic condition in which endometrial stroma and epithelium can be identified'. The main reasons for this change are: (1) to foster the evaluation of fibrosis in studies on endometriosis pathogenesis using animal models; (2) to limit potential false negative diagnoses if pathologists stick stringently to the current definition of endometriosis requiring the demonstration of endometrial stromal and glands; (3) to consider fibrosis as a potential target for treatment in endometriosis. This opinion article is aimed at boosting the attention paid to a largely neglected aspect of the disease. We hope that targeting the fibrotic process might increase success in developing new therapeutic approaches