21 research outputs found

    Autonomous object harvesting using synchronized optoelectronic microrobots

    Get PDF
    Optoelectronic tweezer-driven microrobots (OETdMs) are a versatile micromanipulation technology based on the application of light induced dielectrophoresis to move small dielectric structures (microrobots) across a photoconductive substrate. The microrobots in turn can be used to exert forces on secondary objects and carry out a wide range of micromanipulation operations, including collecting, transporting and depositing microscopic cargos. In contrast to alternative (direct) micromanipulation techniques, OETdMs are relatively gentle, making them particularly well suited to interacting with sensitive objects such as biological cells. However, at present such systems are used exclusively under manual control by a human operator. This limits the capacity for simultaneous control of multiple microrobots, reducing both experimental throughput and the possibility of cooperative multi-robot operations. In this article, we describe an approach to automated targeting and path planning to enable open-loop control of multiple microrobots. We demonstrate the performance of the method in practice, using microrobots to simultaneously collect, transport and deposit silica microspheres. Using computational simulations based on real microscopic image data, we investigate the capacity of microrobots to collect target cells from within a dissociated tissue culture. Our results indicate the feasibility of using OETdMs to autonomously carry out micromanipulation tasks within complex, unstructured environments

    A low-cost paper-based platform for fast and reliable screening of cellular interactions with materials

    Get PDF
    A paper-based platform was developed and tested for studies on basic cell culture, material biocompatibility, and activity of pharmaceuticals in order to provide a reliable, robust and low-cost cell study platform. It is based upon a paper or paperboard support, with a nanostructured Latex coating to provide an enhanced cell growth and sufficient barrier properties. Wetting is Limited to regions of interest using a flexographically printed hydrophobic polydimethylsiloxane Layer with circular non-print areas. The nanostructured coating can be substituted for another coating of interest, or the regions of interest functionalized with a material to be studied. The platform is fully up-scalable, being produced with roll-to-roll rod coating, flexographic and inkjet printing methods. Results show that the platform efficiency is comparable to multi-well plates in colorimetric assays in three separate studies: a cell culture study, a biocompatibility study, and a drug screening study. The color intensity is quantified by using a common office scanner or an imaging device and the data is analyzed by a custom computer software without the need for expensive screening or analysis equipment

    Sex-related Differences in Systemic Sclerosis: A Multicenter Cross-sectional Study From the National Registry of the Italian Society for Rheumatology

    Get PDF
    OBJECTIVE: There is still a great deal to learn about the influence of sex in systemic sclerosis (SSc). In this respect, national registries provide large and homogeneous patient cohorts for analytical studies. We therefore investigated a wide-ranging and well-characterized SSc series with the aim of identifying sex differences in disease expression, with a special focus on demographic, clinical, and serological characteristics. METHODS: A multicenter SSc cohort of 2281 patients, including 247 men, was recruited in the Italian Systemic sclerosis PRogression INvestiGation (SPRING) registry. Demographic data, disease manifestations, serological profile, and internal organ involvement were compared. RESULTS: The overall female/male ratio was 8.2:1. Female/male ratios for limited cutaneous SSc, diffuse cutaneous SSc, and SSc sine scleroderma subsets were 8.7:1, 4.9:1, and 10.7:1, respectively. A shorter time from onset of Raynaud phenomenon to SSc diagnosis, an increased prevalence of the diffuse cutaneous subset, renal crisis, and digital ulcers were found in males, whereas a significantly higher percentage of sicca syndrome, serum antinuclear antibodies, antiextractable nuclear antigens, anti-La/SSB, and anticentromere protein B was detected in the female group. Males exhibited lower left ventricular ejection fraction, as well as higher prevalence of conduction blocks, arrhythmias, ground glass, and honeycombing. Moreover, forced vital capacity and total lung capacity were medially lower in men than in women. Finally, males were more frequently treated with immunosuppressive drugs. CONCLUSION: Our study further supports the presence of several sex-related differences in patients with SSc. These differences were pronounced in the severity of cutaneous, peripheral vascular, and cardiopulmonary involvement for male patients, whereas an increased prevalence of sicca syndrome and a specific autoantibody profile characterized the female sex

    Practice pattern for the use of intravenous iloprost for the treatment of peripheral vasculopathy in systemic sclerosis: A case–control study from the Italian national multicenter “SPRING” (Systemic Sclerosis Progression InvestiGation) Registry

    Get PDF
    Background: Intravenous iloprost has been widely used for the treatment of systemic sclerosis peripheral vasculopathy. No agreement has been found on the regimen and the dosage of intravenous iloprost in different scleroderma subset conditions. This study aimed to evaluate the modalities of intravenous iloprost administration within a large cohort of systemic sclerosis patients from the SPRING Registry and to identify any associated clinical-demographic, instrumental or therapeutic data.Patients and Methods: Data of systemic sclerosis patients treated with intravenous iloprost for at least 1 year (case group) were retrospectively analyzed, including different timing and duration of intravenous iloprost session, and compared with those of untreated patients (control group).Results: Out of 1895 analyzed patients, 937 (49%) received intravenous iloprost treatment, while 958 (51%) were assigned to the control group. Among cases, about 70% were treated every 4 weeks, 24% with an interval of more than 4 weeks, and only 6% of less than 4 weeks. Most patients receiving the treatment every 4 weeks, or less, underwent infusion cycle for 1 day only, while if it was scheduled with an interval of more than 4 weeks, a total number of 5 consecutive days of infusions was the preferred regimen. The comparison between the two groups revealed that patients treated with intravenous iloprost had a higher frequency of DUs (p < 0.001), pitting scars (p < 0.001), diffuse cutaneous involvement (p < 0.001), interstitial lung disease (p < 0.002), as well as higher rates of anti-topoisomerase I, "late" scleroderma pattern at nailfold videocapillaroscopy. These findings were confirmed by multivariate analysis.Conclusion: Our data provide a picture on the Italian use of intravenous iloprost among systemic sclerosis patients and showed that it was usually employed in patients with a more aggressive spectrum of the disease. The disparity of intravenous iloprost treatment strategies in the different centers suggests the need of a rational therapeutical approach based on the clinical characteristics of different patients' subsets

    Geographical heterogeneity of clinical and serological phenotypes of systemic sclerosis observed at tertiary referral centres. The experience of the Italian SIR-SPRING registry and review of the world literature

    Get PDF
    Introduction: Systemic sclerosis (SSc) is characterized by a complex etiopathogenesis encompassing both host genetic and environmental -infectious/toxic- factors responsible for altered fibrogenesis and diffuse microangiopathy. A wide spectrum of clinical phenotypes may be observed in patients' populations from different geographical areas. We investigated the prevalence of specific clinical and serological phenotypes in patients with definite SSc enrolled at tertiary referral centres in different Italian geographical macro-areas. The observed findings were compared with those reported in the world literature.Materials and methods: The clinical features of 1538 patients (161 M, 10.5%; mean age 59.8 +/- 26.9 yrs.; mean disease duration 8.9 +/- 7.7 yrs) with definite SSc recruited in 38 tertiary referral centres of the SPRING (Systemic sclerosis Progression INvestiGation Group) registry promoted by Italian Society of Rheumatology (SIR) were obtained and clustered according to Italian geographical macroareas.Results: Patients living in Southern Italy were characterized by more severe clinical and/or serological SSc phenotypes compared to those in Northern and Central Italy; namely, they show increased percentages of diffuse cutaneous SSc, digital ulcers, sicca syndrome, muscle involvement, arthritis, cardiopulmonary symptoms, interstitial lung involvement at HRCT, as well increased prevalence of serum anti-Scl70 autoantibodies. In the same SSc population immunusppressive drugs were frequently employed. The review of the literature underlined the geographical heterogeneity of SSc phenotypes, even if the observed findings are scarcely comparable due to the variability of methodological approaches.Conclusion: The phenotypical differences among SSc patients' subgroups from Italian macro-areas might be correlated to genetic/environmental co-factors, and possibly to a not equally distributed national network of information and healthcare facilities

    An ecotoxicological study on tin- and bismuth-catalysed PDMS based coatings containing a surface-active polymer

    No full text
    Novel films were prepared by condensation curing reaction of a poly(dimethyl siloxane) (PDMS) matrix with bismuth neodecanoate and dibutyltin diacetate catalysts. An ecotoxicological study was performed on the leachates of the coatings using the bacterium Vibrio fischeri, the unicellular alga Dunaliella tertiolecta, the crustacean Artemia salina and the fish Sparus aurata (larvae) as testing organisms. A copper-based self-polishing commercial paint was also tested as reference. The results showed that the tin-catalysed coatings and the copper paint were highly toxic against at least two of the four test organisms, whereas bismuth-catalysed coatings did not show any toxic effect. Moreover, the same biological assessment was also carried out on PDMS coatings containing a surface-active fluorinated polymer. The toxicity of the entire polymeric system resulted only from the tin catalyst used for the condensation curing reaction, as the bismuth catalysed coatings incorporating the surface-active polymer remained atoxic toward all the tested organisms
    corecore