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Sheng Wu Gong Cheng Xue Bao = Chinese... Jul 2021Scaffold-free tissue engineered cell sheet is an emerging technology in biomedical field. It can avoid the adverse effects of scaffold materials, and can be further... (Review)
Review
Scaffold-free tissue engineered cell sheet is an emerging technology in biomedical field. It can avoid the adverse effects of scaffold materials, and can be further assembled to form more complex three-dimensional functional tissues. The construction of cell sheet is mainly based on the culture substrate composed of sensitive materials. By changing the stimulation factors such as temperature, enzyme, light, ion, redox, pH and sugar, the adhesion behavior of the substrate to the cells could be changed to make the cells detach naturally, thus generating the cell sheet. Recent years have seen the development of various simple and efficient construction technologies of cell sheet due to the development of a variety of novel sensitive culture substrates. The resulted cell sheets with excellent performance have greatly expanded their applications. This review summarized the construction methods of tissue engineered cell sheet and discussed the challenges and future perspectives in this field.
Topics: Temperature; Tissue Engineering; Tissue Scaffolds
PubMed: 34327905
DOI: 10.13345/j.cjb.200520 -
Indian Journal of Ophthalmology Dec 2018Rhegmatogenous retinal detachment (RRD) repair is one of the most common vitreoretinal surgeries a surgeon performs. In an ideal scenario, RRD can be repaired with a... (Review)
Review
Rhegmatogenous retinal detachment (RRD) repair is one of the most common vitreoretinal surgeries a surgeon performs. In an ideal scenario, RRD can be repaired with a single surgical intervention; however, despite excellent skill, flawless technique, and the introduction of high-end technology, up to 10% of cases require additional interventions to ultimately repair recurrent detachments. It is thus important to study the outcomes of multiple interventions to understand whether performing repeat vitrectomy on patients with a history of failed surgeries is worthwhile. Thus, recurrent retinal detachment (re-RD) remains a significant challenge for vitreoretinal surgeons as well as the patients considering the economic and the emotional burden of undergoing multiple interventions. The advent of microincision vitrectomy system, perfluorocarbon liquids, and effective intraocular tamponades has opened new doors for managing re-RDs. In this article, we have reviewed and summarized the various causes and approaches for management for optimal anatomical and functional outcomes.
Topics: Disease Management; Humans; Recurrence; Retinal Detachment; Scleral Buckling; Treatment Outcome; Visual Acuity; Vitrectomy
PubMed: 30451176
DOI: 10.4103/ijo.IJO_1212_18 -
Journal of Ophthalmic & Vision Research 2017Giant retinal tears (GRTs) are full-thickness circumferential tears of more than 90 degrees of the retina that are associated with vitreous detachment. They are related... (Review)
Review
Giant retinal tears (GRTs) are full-thickness circumferential tears of more than 90 degrees of the retina that are associated with vitreous detachment. They are related to ocular trauma, high myopia, aphakia, pseudophakia, genetic mutations involving collagen and young age. GRTs comprise 1.5% of all rhegmatogenous retinal detachments and the average age of incidence is 42 years. GRTs are more common in males, as 72% of all cases occur in males. The incidence of GRTs in the general population is estimated to be 0.05 per 100,000 individuals. Common techniques used in the management of GRTs include fluid-air exchange, pneumatic retinopexy, scleral buckling, primary vitrectomy with gas or silicone oil tamponade, and combined scleral buckle-vitrectomies. However, management of GRTs poses a great challenge to physicians due to the high risk of intra- and post-operative complications and the many technical difficulties involved. The advent of perfluorocarbon liquids (PFCL) and the use of micro-incisional surgery for the treatment of GRTs has provided new opportunities for the management of GTRs. Today, retinal reattachment can be achieved in 94-100% of cases.
PubMed: 28299011
DOI: 10.4103/2008-322X.200158 -
Plant-environment Interactions... Aug 2021Leaf level gas-exchange measurements can be made on detached foliage to address the challenge of access to the crown of tall trees. However, detachment may impact leaf...
Leaf level gas-exchange measurements can be made on detached foliage to address the challenge of access to the crown of tall trees. However, detachment may impact leaf gas exchange. This necessitates the study of gas-exchange characteristics of foliage on detached branches to assess the feasibility of using detached branches for gas-exchange analysis. We compared photosynthetic parameters and stomatal conductance in foliage of attached and detached branches of balsam fir [ (L.) Mill.] during the growing season. Data were analyzed using a linear mixed-effect model, with fixed and random effects (branch status and measurement month, and tree number, respectively). Branch detachment had no significant effects on: (i) photosynthesis at the current ambient CO concentration (400 µmol mol, ); (ii) maximum rates of Ribulose-1,5-bisphosphate (RuBP) carboxylation ( ) and regeneration ( ); (iii) the ratio of to (i.e., : ), and (iv) stomatal conductance ( ) during the study period ( = 0.120-0.335). There was a strong seasonal effect on all gas-exchange variables ( ≤ 0.001-0.015). Gas-exchange measurements made on detached foliage during the warm summer months should be performed with care. Reliable gas-exchange measurements can be obtained using balsam fir foliage on detached branches 50-80 cm in length, in cooler growing-season months, up to 30 min after detachment.
PubMed: 37283699
DOI: 10.1002/pei3.10059 -
Journal of Ophthalmic & Vision Research 2018Pregnancy leads to significant changes in the body, which potentially affect the retina. Pregnancy can induce disease, such as that seen in hypertensive retinopathy and... (Review)
Review
Pregnancy leads to significant changes in the body, which potentially affect the retina. Pregnancy can induce disease, such as that seen in hypertensive retinopathy and choroidopathy. It can cause exudative retinal detachments in the HELLP syndrome (hemolysis, elevated liver enzymes and low platelets), disseminated intravascular coagulation (DIC), and thrombotic thrombocytopenic purpura (TTP), and provoke arterial and venous retinal occlusive disease. Pregnancy may also exacerbate pre-existing retinal disease, such as idiopathic central serous chorioretinopathy (ICSC) and diabetic retinopathy. Special consideration needs to be exercised when treating pregnant patients in choosing medications, as well as in selecting diagnostic modalities and surgical methods.
PubMed: 29403592
DOI: 10.4103/jovr.jovr_195_17 -
Frontiers in Robotics and AI 2021Collaborative robots promise to add flexibility to production cells thanks to the fact that they can work not only humans but also humans. The possibility of a direct...
Collaborative robots promise to add flexibility to production cells thanks to the fact that they can work not only humans but also humans. The possibility of a direct physical interaction between humans and robots allows to perform operations that were inconceivable with industrial robots. Collaborative soft grippers have been recently introduced to extend this possibility beyond the robot end-effector, making humans able to directly act on robotic hands. In this work, we propose to exploit collaborative grippers in a novel paradigm in which these devices can be easily attached and detached from the robot arm and used also independently from it. This is possible only with self-powered hands, that are still quite uncommon in the market. In the presented paradigm not only hands can be attached/detached to/from the robot end-effector as if they were simple tools, but they can also remain active and fully functional after detachment. This ensures all the advantages brought in by tool changers, that allow for quick and possibly automatic tool exchange at the robot end-effector, but also gives the possibility of using the hand capabilities and degrees of freedom without the need of an arm or of external power supplies. In this paper, the concept of is introduced and demonstrated through two illustrative tasks conducted with a new tool changer designed for collaborative grippers. The novel tool changer embeds electromagnets that are used to add safety during attach/detach operations. The activation of the electromagnets is controlled through a wearable interface capable of providing tactile feedback. The usability of the system is confirmed by the evaluations of 12 users.
PubMed: 34222348
DOI: 10.3389/frobt.2021.644532 -
Scientific Reports Sep 2021To investigate local cell death differences in the attached and detached retina at different regions in a murine experimental retinal detachment model. Subretinal...
To investigate local cell death differences in the attached and detached retina at different regions in a murine experimental retinal detachment model. Subretinal injection of sodium hyaluronate was performed in eight-week-old C57BL/6J mice. Retinal regions of interest were defined in relation to their distance from the peak of the retinal detachment, as follows: (1) attached central; (2) attached paracentral; (3) detached apex; and (4) detached base. At day 0, the outer nuclear layer cell count for the attached central, attached paracentral, detached apex, and detached base was 1247.60 ± 64.62, 1157.80 ± 163.33, 1264.00 ± 150.7, and 1013.80 ± 67.16 cells, respectively. There were significant differences between the detached base vs. attached central, and between detached base vs. detached apex at day 0. The detached apex region displayed a significant and progressive cell count reduction from day 0 to 14. In contrast, the detached base region did not show progressive retinal degeneration in this model. Moreover, only the detached apex region had a significant and progressive cell death rate compared to baseline. Immediate confounding changes with dramatic differences in cell death rates are present across regions of the detached retina. We speculate that mechanical and regional differences in the bullous detached retina can modify the rate of cell death in this model.
Topics: Animals; Cell Death; Disease Models, Animal; Fluorescent Antibody Technique; Male; Mice; Mice, Inbred C57BL; Photoreceptor Cells, Vertebrate; Retinal Detachment
PubMed: 34552137
DOI: 10.1038/s41598-021-97947-4 -
Biophysical Journal Nov 2020Kinesin-1 is an ATP-driven molecular motor that transports cellular cargo along microtubules. At low loads, kinesin-1 almost always steps forward, toward microtubule...
Kinesin-1 is an ATP-driven molecular motor that transports cellular cargo along microtubules. At low loads, kinesin-1 almost always steps forward, toward microtubule plus ends, but at higher loads, it can also step backward. Backsteps are usually 8 nm but can be larger. These larger backward events of 16 nm, 24 nm, or more are thought to be slips rather than steps because they are too fast to consist of multiple, tightly coupled 8-nm steps. Here, we propose that not only these larger backsteps, but all kinesin-1 backsteps, are slips. We show first that kinesin waits before forward steps for less time than before backsteps and detachments; second, we show that kinesin waits for the same amount of time before backsteps and detachments; and third, we show that by varying the microtubule type, we can change the ratio of backsteps to detachments without affecting forward stepping. Our findings indicate that backsteps and detachments originate from the same state and that this state arises later in the mechanochemical cycle than the state that gives rise to forward steps. To explain our data, we propose that, in each cycle of ATP turnover, forward kinesin steps can only occur before Pi release, whereas backslips and detachments can only occur after Pi release. In the scheme we propose, Pi release gates access to a weak binding K⋅ADP-K⋅ADP state that can slip back along the microtubule, re-engage, release ADP, and try again to take an ATP-driven forward step. We predict that this rescued detachment pathway is key to maintaining kinesin processivity under load.
Topics: Adenosine Triphosphate; Hydrolysis; Kinesins; Kinetics; Microtubules
PubMed: 33091340
DOI: 10.1016/j.bpj.2020.09.034 -
IScience Feb 2020Achieving efficient and biocompatible detachment between adhered wet materials (i.e., tissues and hydrogels) is a major challenge. Recently, photodetachable topological...
Achieving efficient and biocompatible detachment between adhered wet materials (i.e., tissues and hydrogels) is a major challenge. Recently, photodetachable topological adhesion has shown great promise as a strategy for conquering this hurdle. However, this photodetachment was triggered by UV light with poor biocompatibility and penetration capacity. This study describes near-infrared (NIR) light-detached topological adhesion based on polyacrylic acid coated upconverting nanoparticles (UCNP@PAA) and a photodetachable adhesive (termed Cell-Fe). Cell-Fe is a coordinated topological adhesive consisting of carboxymethylcellulose and Fe that can be photodecomposed by UV light. To prepare a substrate for NIR-detached topological adhesion, UCNP@PAA and Cell-Fe were mixed and brushed on the surface of the model adherent. The UCNP@PAA can harvest NIR light and convert it into UV light, triggering the decomposition of the Cell-Fe and inducing the detachment. This NIR-detached topological adhesion is also feasible in deep tissue because of the ability of NIR light to penetrate tissue.
PubMed: 31986480
DOI: 10.1016/j.isci.2020.100832 -
Taiwan Journal of Ophthalmology 2018In this review, we present a concise summary of the more commonly seen types of retinal detachments (RDs) that one can encounter in pediatric patients. A spectrum of... (Review)
Review
In this review, we present a concise summary of the more commonly seen types of retinal detachments (RDs) that one can encounter in pediatric patients. A spectrum of diseases from rhegmatogenous RD in Stickler syndrome, Marfan syndrome, and choroidal coloboma to exudative RD in Coats disease, to tractional RD in persistent fetal vasculature, and combined RDs in familial exudative vitreoretinopathy are described with the management pearls for each.
PubMed: 30637194
DOI: 10.4103/tjo.tjo_104_18