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Materials (Basel, Switzerland) Jan 2021Cell therapy usually accompanies cell detachment as an essential process in cell culture and cell collection for transplantation. However, conventional methods based on...
Cell therapy usually accompanies cell detachment as an essential process in cell culture and cell collection for transplantation. However, conventional methods based on enzymatic cell detachment can cause cellular damage including cell death and senescence during the routine cell detaching step due to an inappropriate handing. The aim of the current study is to apply the pH-responsive degradation property of poly (amino ester) to the surface of a cell culture dish to provide a simple and easy alternative method for cell detachment that can substitute the conventional enzyme treatment. In this study, poly (amino ester) was modified (cell detachable polymer, CDP) to show appropriate pH-responsive degradation under mild acidic conditions (0.05% (w/v) CDP, pH 6.0) to detach stem cells (human adipose tissue-derived stem cells (hADSCs)) perfectly within a short period (less than 10 min). Compared to conventional enzymatic cell detachment, hADSCs cultured on and detached from a CDP-coated cell culture dish showed similar cellular properties. We further performed in vivo experiments on a mouse hindlimb ischemia model (1.0 × 10 cells per limb). The in vivo results indicated that hADSCs retrieved from normal cell culture dishes and CDP-coated cell culture dishes showed analogous therapeutic angiogenesis. In conclusion, CDP could be applied to a pH-responsive cell detachment system as a simple and easy nonenzymatic method for stem cell culture and various cell therapies.
PubMed: 33498583
DOI: 10.3390/ma14030491 -
ISRN Pharmacology 2012Exposure of cancer cells to anticancer agents in cultures induces detachment of cells that are usually considered dead. These drug-induced detached cells (D-IDCs) may...
Exposure of cancer cells to anticancer agents in cultures induces detachment of cells that are usually considered dead. These drug-induced detached cells (D-IDCs) may represent a clinical problem for chemotherapy since they may survive anoikis, enter the circulation, invade other tissues and resume proliferation, creating a metastasis, especially in tissues where the bioavailability of anticancer agents is not enough to eliminate all cancer cells. In this study we evaluated the antiproliferative effect of menadione : sodium orthovanadate (M : SO) combination on A549 lung cancer cells as well as the ability of M : SO to induce cell detachment. In addition, we followed the fate and chemosensitivity of M : SO-induced detached cells. Using transwell chambers, we found that a fraction of the M : SO-induced detached cells were viable and, furthermore, were able to migrate, re-attach, and resume proliferation when re-incubated in drug-free media. The total elimination of A549 detachment-resistant cells and M : SO-induced detached cells were successfully eliminated by equivalent M : SO concentration (17.5 μM : 17.5 μM). Thus, M : SO prevented cell migration. Similar results were obtained on DBTRG.05MG human glioma cells. Our data guarantee further studies to evaluate the in vivo occurrence of D-IDCs, their implications for invasiveness and metastasis and their sensitivity to anticancer drugs.
PubMed: 22957270
DOI: 10.5402/2012/307102 -
Acta Ophthalmologica May 2022To provide a detailed analysis of risk factors for pseudophakic retinal detachments (PRD) and pseudophakic retinal breaks (PRB).
PURPOSE
To provide a detailed analysis of risk factors for pseudophakic retinal detachments (PRD) and pseudophakic retinal breaks (PRB).
MATERIALS AND METHODS
We reviewed the medical records of cataract surgeries between 1996 and 2017 at a tertiary care hospital in Austria. A Cox proportional-hazard regression model was used to analyse risk factors for PRD and PRB.
RESULTS
Sixty-five thousand six hundred and sixty-two eyes (45 043 patients) underwent phacoemulsification, and 393 eyes (cumulative incidence 0.6%) were diagnosed with PRD (327 eyes) or PRB (66 eyes) during the follow-up (median 7.1 years, range 0-21). Calculation of adjusted hazard ratios (HR) revealed a hierarchy of risk factors for either event including (from the highest to the lowest risk) posterior capsular rupture (PCR), patient age <65 years (compared with the age group >75 years), male gender and high myopia. Diabetes mellitus was associated with a lower risk. PCR was the strongest risk factor for PRD both in patients with and without perioperative vitrectomy (i.e. vitreous loss), but time to PRD was significantly reduced only following PCR with vitrectomy.
CONCLUSIONS
Posterior capsular rupture, young patient age, male gender and high myopia were risk factors for PRD, but diabetes mellitus was associated with a lower risk. PCR had the strongest association with PRD, regardless of the need for perioperative vitrectomy due to vitreous loss. Time to PRD was reduced in patients with PCR and vitrectomy compared with PCR without the need for vitrectomy or uneventful surgery.
Topics: Aged; Humans; Male; Myopia; Postoperative Complications; Pseudophakia; Retinal Detachment; Retinal Perforations; Retrospective Studies; Risk Factors; Vitrectomy
PubMed: 34258879
DOI: 10.1111/aos.14974 -
Annals of the Royal College of Surgeons... Jan 1976This lecture presents the experience in 200 implantations of human eye-bank vitreous through the pars plana of eyes with complicated retinal detachments. Though the...
This lecture presents the experience in 200 implantations of human eye-bank vitreous through the pars plana of eyes with complicated retinal detachments. Though the success rate was modest, it shows that a large-bore instrument can be passed into the vitreous cavity of the eye with relative impunity and sets the stage for the present popular machine vitrectomy. In addition, the paper presents the author's experience with human vitreous transplantation by the 'open sky' transcorneal technique for otherwise hopeless vitreous opacities.
Topics: Eye Banks; Hemorrhage; Humans; Methods; Retinal Detachment; Surgical Procedures, Operative; Suture Techniques; Tissue Preservation; Transplantation, Homologous; Vitreous Body
PubMed: 769647
DOI: No ID Found -
BMC Medical Genetics Jan 2018Osteogenesis imperfecta (OI) is a rare primarily autosomal dominant condition in which the connective tissues of bones, ligaments and sclerae do not form properly....
BACKGROUND
Osteogenesis imperfecta (OI) is a rare primarily autosomal dominant condition in which the connective tissues of bones, ligaments and sclerae do not form properly. Typically, mutations in COL1A1 and COL1A2 genes lead to the defective formation or quantity of type I collagen, the principle matrix in these tissues. Molecular genetic studies have now elucidated multiple genetic subtypes of the disorder but little literature exists on the risk of retinal tears and detachments in OI.
CASE PRESENTATION
We report the first case of a child with a rare recessive type of OI, subtype VIII, resulting from a P3H1 (also known as LEPRE1) gene mutation presenting with bilateral giant retinal tears and the surgical challenges encountered in performing retinal detachment repair due to scleral thinning. The P3H1 gene encodes for prolyl 3-hydroxylase 1 which is involved in the post-translational modification of not only collagen type I but also types II and V which when mutated may result in pathological posterior vitreous detachment (PVD) and giant retinal tear detachments.
CONCLUSIONS
Genetic analyses are increasingly important in such cases and may guide patient monitoring and potential prophylactic treatment, known to significantly reduce the probability of giant retinal tear detachments in other high-risk collagenopathies such as Stickler Syndrome Type I.
Topics: Child; Collagen Type I; Collagen Type I, alpha 1 Chain; Collagen Type II; Collagen Type V; Genes, Recessive; Genetic Testing; Humans; Male; Membrane Glycoproteins; Osteogenesis Imperfecta; Prolyl Hydroxylases; Protein Processing, Post-Translational; Proteoglycans; Retinal Detachment; Retinal Perforations
PubMed: 29329516
DOI: 10.1186/s12881-018-0521-0 -
Ophthalmology Science Sep 2023To determine the treatment patterns and outcomes of pediatric retinal detachments (RDs) associated with hereditary vitreoretinopathies.
PURPOSE
To determine the treatment patterns and outcomes of pediatric retinal detachments (RDs) associated with hereditary vitreoretinopathies.
DESIGN
Retrospective cohort analysis using IRIS® Registry (Intelligent Research in Sight) database.
PARTICIPANTS
Patients < 18 years old with a rhegmatogenous RD and a systemic disorder associated with vitreoretinal degeneration (e.g., Stickler syndrome) or other malformation of the vitreous from 2013-2019.
METHODS
Cases were identified using International Classification of Diseases, Ninth and Tenth Revisions (ICD-9, ICD-10) diagnostic codes from the IRIS® Registry cohort. Other hereditary vitreoretinopathies that are not encoded by specific ICD code(s) were captured by text search. Nonspecific vitreous abnormality ICD codes were also included. Exclusion criteria included traumatic retinal detachments using ICD codes for ocular trauma and serous or exudative retinal detachment. Surgical procedures were identified using Current Procedural Terminology (CPT) codes for repair of retinal detachment. Baseline demographic information collected included age, gender, race/ethnicity, geographic region of the provider location, and health insurance status.
MAIN OUTCOME MEASURES
Main outcomes measured in this study were average time to first surgery, number of eyes presenting with bilateral detachments, and choice of initial surgical procedure.
RESULTS
A total of 2115 eyes of 1722 patients were identified (mean age, 10.4 years; 58% male). The median time to first surgery was 7 days (interquartile range, 40 days). One thousand four hundred seven eyes of 1134 patients had ≥ 1 year of follow-up, with 506 eyes (36%) developing a fellow eye RD. Thirty-three percent of patients presenting with bilateral detachments, and 349 eyes had initial RD surgery within 1 year of the index date documented by CPT code. Fellow eye detachment occurred a mean of 32 days after initial presentation. The mean number of surgeries per eye within 1 year was 1.68. Best-corrected visual acuity did not improve from a baseline 20/54 to 20/62. The initial procedure was most commonly complex RD repair (n = 176), followed by scleral buckle (n = 102), pars plana vitrectomy (n = 89), laser (n = 59), cryotherapy (n = 5), and pneumatic retinopexy (n = 5). There were 51 new diagnoses of glaucoma and 37 new diagnoses of aphakia within 1 year after the surgical procedure.
CONCLUSIONS
IRIS Registry data provide insight into rare pediatric vitreoretinopathy-associated RDs, which have a high rate of reoperation and fellow eye involvement.
FINANCIAL DISCLOSURES
Proprietary or commercial disclosure may be found after the references.
PubMed: 36950302
DOI: 10.1016/j.xops.2023.100273 -
Journal of the Royal Society of Medicine Dec 1990
Review
Topics: Humans; Retina; Retinal Detachment; Retinal Perforations; Vitrectomy
PubMed: 2269963
DOI: 10.1177/014107689008301210 -
Communications Biology 2019Cell detachment is essential in culturing adherent cells. Trypsinization is the most popular detachment technique, even though it reduces viability due to the damage to... (Comparative Study)
Comparative Study
Cell detachment is essential in culturing adherent cells. Trypsinization is the most popular detachment technique, even though it reduces viability due to the damage to the membrane and extracellular matrix. Avoiding such damage would improve cell culture efficiency. Here we propose an enzyme-free cell detachment method that employs the acoustic pressure, sloshing in serum-free medium from intermittent traveling wave. This method detaches 96.2% of the cells, and increases its transfer yield to 130% of conventional methods for 48 h, compared to the number of cells detached by trypsinization. We show the elimination of trypsinization reduces cell damage, improving the survival of the detached cells. Acoustic pressure applied to the cells and media sloshing from the intermittent traveling wave were identified as the most important factors leading to cell detachment. This proposed method will improve biopharmaceutical production by expediting the amplification of tissue-cultured cells through a more efficient transfer process.
Topics: Animals; CHO Cells; Cell Adhesion; Cell Proliferation; Cell Separation; Cricetulus; Culture Media, Serum-Free; DNA Damage; Equipment Design; Membrane Proteins; Microscopy, Electron, Scanning; Trypsin; Ultrasonic Waves
PubMed: 31701022
DOI: 10.1038/s42003-019-0638-5 -
Biophysical Journal Mar 2022By analyzing the distributions of focal adhesion (FA) lifetimes from different cell types, we found that a gamma distribution best matched the experimental...
By analyzing the distributions of focal adhesion (FA) lifetimes from different cell types, we found that a gamma distribution best matched the experimental distributions. In all but one case, it was a unimodal, non-symmetric gamma distribution. We used a mathematical model of cell motion to help understand the mechanics and data behind the FA lifetime distributions. The model uses a detach-rate function to determine how long an FA will persist before it detaches. The detach-rate function that produced distributions with a best-fit gamma curve that closely matched that of the data was both force and time dependent. Using the data gathered from the matching simulations, we calculated both the cell speed and mean FA lifetime and compared them. Where available, we also compared this relationship to that of the experimental data and found that the simulation reasonably matches it in most cases. In both the simulations and experimental data, the cell speed and mean FA lifetime are related, with longer mean lifetimes being indicative of slower speeds. We suspect that one of the main predictors of cell speed for migrating cells is the distribution of the FA lifetimes.
Topics: Cell Adhesion; Cell Movement; Computer Simulation; Focal Adhesions
PubMed: 35143774
DOI: 10.1016/j.bpj.2022.02.003 -
The Journal of Cell Biology Nov 1982We have described a monoclonal antibody that rounds and detaches chick skeletal myoblasts and myotubes from extracellular substrata. The antibody also inhibits the...
We have described a monoclonal antibody that rounds and detaches chick skeletal myoblasts and myotubes from extracellular substrata. The antibody also inhibits the attachment of myogenic cells to a gelatin-coated substratum but has no detectable effect on myoblast fusion. The cellular response to antibody treatment varies with differentiation and cell type. Young myoblasts and myotubes are rapidly rounded and detached by the antibody. Older myotubes require longer incubation times or higher antibody titers for rounding and detachment. Chick embryo fibroblasts, cardiac cells, and neurons are not similarly rounded and remain attached. Since the antibody also detaches cells from embryonic muscle tissue explants, the cell-substratum interaction perturbed by the antibody appears relevant to the in vivo interaction of myogenic cells with their extracellular matrices. Binding studies using iodinated antibody revealed 2-4 x 10(5) sites per myoblast with an apparent Kd in the range of 2-5 x 10(-9) molar. Embryo fibroblasts bind antibody as well and display approximately twice the number of binding sites per cell. The fluorescence distribution of antigen on myoblasts and myotubes is somewhat punctate and particularly bright along the edge of the myotube. The distribution on fibroblasts was also punctate and was particularly bright along the cell periphery and portions of stress fibers. For both cell types the binding was distinctly different than that reported for collagen, fibronectin, and other extracellular molecules. The antigen, as isolated by antibody affinity chromatography, inhibits antibody-induced rounding. SDS PAGE reveals two unique polypeptides migrating in the region of approximately 120 and 160 kilodaltons (kd). The most straightforward mechanism for the antibody-induced rounding and detachment is the perturbation of a membrane molecule involved in adhesion. The hypothesized transmembrane link between extracellular macromolecules and the cytoskeleton provides an obvious candidate.
Topics: Animals; Antibodies, Monoclonal; Cell Adhesion; Cell Differentiation; Cell Fusion; Cells, Cultured; Chick Embryo; Epitopes; Fibroblasts; Membrane Proteins; Muscles
PubMed: 6183279
DOI: 10.1083/jcb.95.2.654