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Opto-fluidically multiplexed assembly and micro-robotics

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Light(Science & Applications) 2024年第3期13卷 544-554页

作者： elena Erben Weida Liao Antonio Minopoli nicola Maghelli Eric Lauga Moritz Kreysing Max Planck Institute of Molecular Cell Biology and Genetics Dresden 01307Germany Center for Systems Biology Dresden 01307Germany Institute of Biological and Chemical Systems–Biological Information Processing.Karlsruhe Institute of Technology(KIT) Eggenstein-Leopoldshafen 76344Germany Department of Applied Mathematics and Theoretical Physics University of CambridgeCambridge CB30WAUK

Techniques for high-definition micromanipulations,such as optical tweezers,hold substantial interest across a wide range of ***,their applicability remains constrained by material properties and laser *** while microfluidic manipulations have been suggested as an alternative,their inherent capabilities are limited and further hindered by practical challenges of implementation and *** we show that the iterative application of laser-induced,localized flow fields can be used for the relative positioning of multiple micro-particles,irrespectively of their material *** to the standing theoretical proposal,our method keeps particles mobile,and we show that their precision manipulation is non-linearly accelerated via the multiplexing of temperature stimuli below the heat diffusion *** resulting flow fields are topologically rich and mathematically *** represent unprecedented microfluidic control capabilities that are illustrated by the actuation of humanoid micro-robots with up to 30 degrees of freedom,whose motions are sufficiently well-defined to reliably communicate personal characteristics such as gender,happiness and *** results constitute high-definition micro-fluidic manipulations with transformative potential for assembly,micro-manufacturing,the life sciences,robotics and optohydraulically actuated micro-factories.

关键词： manipulation fluid assembly

Dielectric Spectroscopy, a Modern Method for Microstructural Characterization of Materials

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材料科学与工程（中英文A版） 2014年第1期4卷 18-26页

作者： doina elena Gavrila Department of Physics University "Politehnica" Bucharest Splaiul Independentei 313 Romania

Cognitive impairment in multiple sclerosis: lessons from cerebrospinal fluid biomarkers

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Neural Regeneration Research 2021年第1期16卷 36-42页

作者： Lorenzo Gaetani nicola Salvadori elena Chipi Lucia Gentili Angela Borrelli Lucilla Parnetti Massimiliano Di Filippo Section of Neurology Department of MedicineUniversity of PerugiaPerugiaItaly

Cognitive impairment is a common clinical manifestation of multiple sclerosis,but its pathophysiology is not completely *** and grey matter injury together with synaptic dysfunction do play a *** measurement of biomarkers in the cerebrospinal fluid and the study of their association with cognitive impairment may provide interesting in vivo evidence of the biological mechanisms underlying multiple sclerosis-related cognitive *** far,only a few studies on this topic have been published,giving interesting results that deserve further *** fluid biomarkers of different pathophysiological mechanisms seem to reflect different neuropsychological patterns of cognitive deficits in multiple *** aim of this review is to discuss the studies that have correlated cerebrospinal fluid markers of immune,glial and neuronal pathology with cognitive impairment in multiple *** preliminary,these findings suggest that cerebrospinal fluid biomarkers show some correlation with cognitive performance in multiple sclerosis,thus providing interesting insights into the mechanisms underlying the involvement of specific cognitive domains.

关键词： biomarkers cerebrospinal fluid cognitive impairment information processing speed memory multiple sclerosis

Long-term normothermic machine perfusion of fatty livers:towards transplanting untransplantable livers?

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Hepatobiliary Surgery and Nutrition 2024年第4期13卷 681-685页

作者： Damiano Patrono nicola De Stefano elena Vissio Alessandro Gambella Renato Romagnoli General Surgery 2U–Liver Transplant Unit Azienda Ospedaliero Universitaria Cittàdella Salute e della Scienza di TorinoTurinItaly Pathology Unit Azienda Ospedaliero Universitaria Cittàdella Salute e della Scienza di TorinoTurinItaly Department of Medical Sciences University of TurinTurinItaly

Since the very early days of clinical liver transplantation(LT),transplant surgeons and professionals have been confronted with the increased risk of failure associated with the use of fatty liver grafts(1).Notwithstanding the wide variability in steatosis assessment across different centers and pathologists(2),utilization of livers with moderate(≥30%)or severe(≥60%)macrovesicular steatosis has been consistently associated with an increased risk of primary non-function,early allograft dysfunction,acute kidney injury,as well as inferior graft and patient survival(3).The mechanisms behind the increased susceptibility of steatotic livers to ischemia-reperfusion injury(IRI)are multiple,including disturbances to microcirculation due to sinusoidal narrowing,increased oxidative stress upon reperfusion and enhanced lipid peroxidation,leading to an increased release of inflammatory mediators like IL6,IL1βand so-called damage associated molecular patterns(DAMP),like cell-free DNA and mitochondrial ***,this is reflected by hepatocyte death by necrosis rather than apoptosis,pseudopeliotic steatosis(i.e.,the expulsion of lipid droplets into the extracellular space)and lately,by tissue remodelling and fibrosis(4,5).

关键词： Liver transplantation(LT) steatosis macrovesicular steatosis large droplet fat normothermic machine perfusion

Highly sensitive force measurements in an optically generated, harmonic hydrodynamic trap

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eLight 2021年第1期1卷 69-77页

作者： Iliya D.Stoev Benjamin Seelbinder elena Erben nicola Maghelli Moritz Kreysing Max Planck Institute of Molecular Cell Biology and Genetics Pfotenhauerstraße 10801307 DresdenGermany. Centre for Systems Biology Pfotenhauerstraße 10801307 DresdenGermany. Cluster of Excellence Physics of Life TU DresdenDresdenGermany.

The use of optical tweezers to measure forces acting upon microscopic particles has revolutionised fields from material science to cell ***,despite optical control capabilities,this technology is highly constrained by the material properties of the probe,and its use may be limited due to concerns about the effect on biological *** we present a novel,optically controlled trapping method based on light-induced hydrodynamic ***,we leverage optical control capabilities to convert a translationally invariant topological defect of a flow field into an attractor for colloids in an effectively one-dimensional harmonic,yet freely rotatable *** the need to stabilise particle dynamics along an unstable axis,this novel trap closely resembles the isotropic dynamics of optical *** magnetic beads,we explicitly show the existence of a linear force-extension relationship that can be used to detect femtoNewton-range forces with sensitivity close to the thermal *** force measurements remove the need for laser-particle contact,while also lifting material constraints,which renders them a particu-larly interesting tool for the life sciences and engineering.

关键词： Force measurements Optofluidics Hydrodynamic trap Thermoviscous flows

Protective effect of resveratrol against cadmium-induced toxicity on ovine oocyte in vitro maturation and fertilization

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Journal of Animal Science and Biotechnology 2023年第1期14卷 152-165页

作者： Anna Rita Piras Federica Ariu Alessio Maltana Giovanni Giuseppe Leoni nicola Antonio Martino Antonella Mastrorocco Maria elena Dell’Aquila Luisa Bogliolo Department of Veterinary Medicine University of Sassari07100 SassariSardiniaItaly. Department of Biosciences Biotechnologies&BiopharmaceuticsUniversity of Bari Aldo Moro70125 BariItaly.

Background:Heavy metal cadmium(Cd)is a widespread environmental contaminant with a potential toxicity that might negatively affect female reproduction and *** has been reported that Cd exposure impaired the quality of oocytes and led to a defective maturation and fertilization,through oxidative stress ***(Res)is a natural polyphenol with strong antioxidant properties that exhibited protective role in preventing oocyte redox homeostasis disruption and quality ***,we explored whether the addition of Res to in vitro maturation(IVM)medium might act as a protection against Cd-induced toxicity on ovine oocyte maturation and ***,we evaluated the effect of supplementing IVM medium with two different Res concentrations(1and 2μmol/L)on nuclear maturation and fertilization of oocytes matured under CdCl2(2μmol/L)***,the concentration of 1μmol/L Res was selected to analyse the effects of this compound on intracellular ROS levels,mitochondrial(mt)distribution and activity,chromatin configuration,cytoskeleton morphology,cortical granules(CGs)distribution and mRNA expression of genes associated with cellular response to oxidative stress(***1,SOD 1,GPX1,GSR,CAT)in Cd-exposed in vitro matured ***:We found that 1μmol/L Res restored the reduced oocyte meiotic competence induced by Cd exposure as well as,Res sustained oocyte ability to be normally fertilized and decreased polyspermic fertilization at both tested ***,we demonstrated that 1μmol/L Res mitigated Cd-induced alterations of oocyte cytoplasmic maturation by reducing reactive oxygen species(ROS)accumulation,preventing mt dysfunction,maintaining the correct meiotic spindle and cortical F-actin assembly and the normal cortical granule distribution as well as up-regulating SIRT1,SOD1 and GPX1 ***:Taken together,our findings highlighted the beneficial influence exerted by Res in preventing Cdinduced disturbance of

关键词： Cadmium In vitro maturation Oocyte Ovine Resveratrol

Localization of AKAP4 and tubulin proteins in sperm with reduced motility

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Asian Journal of Andrology 2007年第5期9卷 641-649页

作者： elena Moretti Giacomo Scapigliati nicola Antonio Pascarelli Baccio Baccetti Giulia Collodel Department of General Surgery Biology Section University of Siena Regional Referral Center for Male InfertilitySiena 53100 Italy

Aim： To perform screening, related to A-kinase anchoring proteins 4 （AKAP4） and tubulin proteins, in spermatozoa with absent or severely reduced motility in order to detect the status of the fibrous sheath and the axonemal structure. Methods： An immunocytochemical study of tubulin, used as a positive control, and AKAP4 was carded out to detect the presence and the distribution of these proteins in different sperm samples. The morphological characteristics of sperm were studied by transmission electron microscope （TEM） and the results were elaborated using a formula reported in previous studies. PCR was carried out on DNA extracted from peripheral blood lymphocytes to analyse partial sequences of the Akap4 and Akap3 genes. Results： Immunolabelling of tubulin and AKAP4 showed different patterns, which led us to divide the patients into groups. In group I, the absence of AKAP4 and tubulin was revealed, although these patients did not show alterations in the Akap4/Akap3 binding site. TEM evaluation highlighted that a high presence of necrosis was associated with total sperm immotility. In group Ⅱ, a regular AKAP4 and tubulin signal was present, although motility was reduced and TEM analysis revealed the presence of immaturity. In group Ⅲ, in which a weak AKAP4 label associated with normal tubulin staining and reduced motility was observed, a severe disorganization of the fibrous sheath was highlighted by TEM. Conclusion： While the role of AKAP4 in sperm motility is unclear, absent or weak AKAP4-1abelling seems to be associated with absent or weak sperm motility.

关键词： AKAP4 immunocytochemistry motility, sperm transmission electron microscope

18,X,Y aneuploidies and transmission electron microscopy studies in spermatozoa from five carriers of different reciprocal translocations

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Asian Journal of Andrology 2009年第3期11卷 325-332页

作者： elena Moretti nicola Antonio Pascarelli Valentina Giannerini Michela Geminiani Cecilia Anichini Giulia Collodel Department of Biomedical Sciences Applied Biology Section University of Siena Siena 53100 Italy Department of Pediatrics Obstetrics and Reproductive Medicine University of Siena Siena 53100 Italy

We analysed ejaculated spermatozoa from five infertile men with different balanced reciprocal translocations to contribute to the study of meiotic segregation of chromosomes 18, X and Y and also to evaluate sperm morphology by transmission electron microscopy （TEM） analysis. Conventional lymphocyte karyotype analyses highlighted dif- ferent reciprocal balanced translocations： t（12; 13）, t（4;9）, t（X;8）, t（8; 10） and t（3; 16）. Semen analysis was performed by light and TEM. Fluorescence in situ hybridization was performed directly on sperm nuclei using centromeric probes for chromosomes 18, X and Y. The carriers of the balanced reciprocal translocations considered in the present study showed a very similar pattern of sperm pathologies： diffused presence of apoptosis and immaturity. All patients showed meiotic segregation derangements, highlighted by the presence of sperm diploidies and sex chromosome disomies particularly related to the failure of the first meiotic division. However, an increased incidence of chromosome 18 aneuploidy was detected in spermatozoa from t（X;8） and t（8;10） carriers. We have also reported values from sex chromosomes such as t（X;8）, although the X chromosome was involved in translocation. Since patients with reciprocal translocations and spermatogenetic impairment are candidates for intracytoplasmic sperm injection cycles, the study of sperm parameters, and particularly of the level of aneuploidy rates, would provide better information for couples at risk and would contribute to the data in the literature for a better understanding of the effects of chromosomal rearrangement on the whole meiotic process and, in particular, on chromosomes not involved in translocation.

关键词： electron microscopy fluorescence in situ hybridization altered karyotype spermatozoa reciprocal translocation

Vitamin D and acute myocardial infarction

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World Journal of Cardiology 2017年第1期9卷 14-20页

作者： Valentina Milazzo Monica De Metrio nicola Cosentino Giancarlo Marenzi elena Tremoli Centro Cardiologico Monzino I.R.C.C.S.20138 MilanItaly

Vitamin D deficiency is a prevalent condition,cutting across all ethnicities and among all age groups,and occurring in about 30%-50% of the population. Besides vitamin D established role in calcium homeostasis,its deficiency is emerging as a new risk factor for coronary artery disease. Notably,clinical investigations have suggested that there is an association between hypovitaminosis D and acute myocardial infarction(AMI). Not only has it been linked to incident AMI,but also to increased morbidity and mortality in this clinical setting. Moreover,vitamin D deficiency seems to predispose to recurrent adverse cardiovascular events,as it is associated with post-infarction complications and cardiac remodeling in patients with AMI. Several mechanisms underlying the association between vitamin D and AMI risk can be involved. Despite these observational and mechanistic data,interventional trials with supplementation of vitamin D are controversial. In this review,we will discuss the evidence on the association between vitamin D deficiency and AMI,in terms of prevalence and prognostic impact,and the possible mechanisms mediating it. Further research in this direction is warranted and it is likely to open up new avenues for reducing the risk of AMI.

关键词： Vitamin D Acute myocardial infarction Incidence Prognosis