scholarly journals Development of an in-situ printing system with human platelet lysate based bioink to treat corneal perforation

2021 ◽  
Author(s):  
Jingjing You ◽  
Hannah Frazer ◽  
Sepidar Sayyar ◽  
Zhi Chen ◽  
Xiao Liu ◽  
...  
Keyword(s):  
Rheological Behaviour ◽  
Burst Pressure ◽  
Control Group ◽  
Corneal Tissue ◽  
Corneal Perforation ◽  
Cyanoacrylate Glue ◽  
Cell Compatibility ◽  
Printing System

Purpose: Corneal perforation is a clinical emergency. Tissue glue to seal the perforation, and supplementary topical medication represents existing standard treatment. Previously, our group developed a transparent bioink that showed good cell compatibility and accelerated corneal epithelial cells healing in-vitro. This study aims to develop a novel treatment method for corneal perforation using this bioink. Methods: Rheometry was used to measure bioink behaviour at room and corneal surface temperatures. Bioink adhesiveness to porcine skin and burst pressure limit were also measured. Based on rheological behaviour, a hand-held biopen was developed to extrude the bioink onto the cornea. An animal trial (5 New Zealand white rabbits) to compare bioink and cyanoacrylate glue (control group) impact on a 2mm perforation was conducted to evaluate safety and efficacy. Results: Bioink has higher adhesiveness compared to commercial fibrin glue and can withstand burst pressure approximately 6.4x higher than routine intraocular pressure. Bioink-treated rabbits had lower pain score and faster recovery, despite generating similar scar-forming structure after healing compared to controls. No secondary corneal ulcer was generated in rabbits treated with bioink. Conclusions: This study reports a novel in-situ printing system capable of delivering a transparent bioink to the cornea and successfully treating small corneal perforations. Bioink-treated rabbits recovered faster to completely healed perforation and required no additional analgesia. Both groups showed scarred corneal tissue after healing, however no infection and inflammation was observed 3 weeks. The delivery system was easy to use and may represent an alternative treatment for corneal perforation.

Abstract 2877: A Combined Cell Therapy and In Situ Tissue Engineering Approach for Myocardial Repair

Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Manhal Habib ◽  
Keren Shapira ◽  
Oren Caspi ◽  
Gil Arbel ◽  
Amira Gepstein ◽  
...  
Keyword(s):  
Tissue Engineering ◽  
Functional Performance ◽  
Embryonic Stem ◽  
Neonatal Rat ◽  
Favorable Effect ◽  
Control Group ◽  
Myocardial Repair ◽  
Post Injury

Cell replacement and tissue engineering strategies are emerging as novel therapeutic paradigms for myocardial repair. Here we tested the hypothesis that a combined in situ tissue engineering and cell delivery strategy utilizing transplantable hydrogel-embedded cardiomyocytes [either neonatal rat ventricular cardiomyocytes (NRVCMs) or human embryonic stem cell-derived cardiomyocytes (hESC-CMs)] will improve functional performance in the rat infarction model. Methods and results : A novel liquid biodegradable PEGylated fibrinogen was developed, which was proved to be compatible with cardiomyocyte survival and maturation in vitro . Photopolymerization using UV beam results in a rapid liquid to hydrogel transformation. Animals were randomized to injection of saline, NRVCMs alone, the biopolymer alone, or the combined delivery of the biopolymer and the NRVCMs. Histological studies demonstrated the presence of the hydrogel-embedded cardiomyocytes within the scar tissue. The biopolymer was fully absorbed one month following delivery. Echocardiography revealed typical post-infarction remodeling in the control group (saline injection) as manifested by the deterioration of ejection fraction (EF) by 28±3% (from 43±2% at post-injury baseline to 30±2% at 4 weeks). Injection of the biopolymer or NRVCMs alone prevented this remodeling process (39±2% to 39±2% and 43±3% to 43±2% respectively; p<0.05 when compared to controls). Co-injection of the biopolymer and NRVCMs resulted in the best functional outcome with EF improving by 22±8% from 40±4% to 48±4% (p<0.05 when compared to the saline or biopolymer groups and p=0.07 when compared to NRVCM group). Finally, initial studies also demonstrated a favorable effect following the co-injection of the biopolymer together with hESC-CMs (from a baseline value of 45±1% to 47±1%). Similar improvements in all groups were also noted for other remodeling parameters (LV diastolic area and wall motion score) Conclusions: We describe a novel injectable in-situ-forming hydrogel that functions as an efficient cardiomyocyte carrier for both NRVCM and hESC-CMs and acts synergistically with the grafted cells to prevent the unfavorable post-infarction cardiac remodeling and improve ventricular function in rats.

scholarly journals 221.Effects of exogenous gonadotrophin stimulation on ovarian tissue grafts in the mouse

2004 ◽  
Vol 16 (9) ◽  
pp. 221
Author(s):  
H. Yang ◽  
S. Cox ◽  
J. Shaw ◽  
G. Jenkin
Keyword(s):  
Subcutaneous Tissue ◽  
Ovarian Tissue ◽  
Control Group ◽  
Control Groups ◽  
Hybrid Strain ◽  
Tissue Grafts ◽  
And Control

Ovarian tissue grafts commonly contain only limited numbers of follicles. The functional life span and ability to retrieve as many mature oocytes as possible from ovarian grafts is important when grafting is used to restore fertility. This study aimed to determine whether ovarian grafts responded to exogenous hormones in a similar manner to that of in situ ovaries. Ovaries of C57BlxCBA F1 mice were cut in half and grafted to one of three different graft sites in females of the same F1 line; bursal capsule (BC, n = 12), kidney capsule (KC, n = 6), subcutaneous tissue (SC, n = 24). Three weeks after grafting, half of the graft recipients in each group were treated with 5IU PMSG followed by 5IU hCG 48 hours later. Oocytes were collected directly from the grafted ovaries 10 hours after the hCG injection and fertilized in vitro. Oocytes from the ovaries of superovulated normal mice (n = 4) of the same hybrid strain were used as controls. Two-cell embryos were transferred to pseudopregnant recipients and collected at day 15 of gestation or the animals were allowed to go to term. Mature fertilisable MII oocytes were retrieved from stimulated grafts from all graft sites, however, the number (BC 9, KC 5, SC 2 oocytes per ovary) and proportion of two-cell embryos in each grafted group (BC 52%, KC 32%, SC 32%) was significantly (P < 0.05) lower than in the in vivo matured control (16 oocytes, 85% two-cell). The fetal and placental weights of fetuses produced from graft-derived oocytes were not significantly different to the control group. Phenotypically normal pups were born in each of the graft and control groups. In conclusion, ovarian grafts treated with exogenous gonadotrophins produce significantly fewer mature oocytes and two cell embryos compared to in situ ovaries. Work supported by ARC and NIH RFA.

Local Administration of Magnesium Promotes Meniscal Healing Through Homing of Endogenous Stem Cells: A Proof-of-Concept Study

2019 ◽  
Vol 47 (4) ◽  
pp. 954-967 ◽  
Author(s):  
Zheng-Zheng Zhang ◽  
Yun-Feng Zhou ◽  
Wei-Ping Li ◽  
Chuan Jiang ◽  
Zhong Chen ◽  
...  
Keyword(s):  
Stem Cells ◽  
Meniscal Repair ◽  
Control Group ◽  
Suture Repair ◽  
Blank Group ◽  
Absorbable Sutures ◽  
Meniscal Lesions

Background: Although many strategies have been developed to modify the biological and biomechanical environment of the meniscal suture repair to improve the chances of healing, the failure rates remain high. Thus, new methods to promote meniscal regeneration and repair are needed. Hypothesis: Administration of magnesium (via a repair using magnesium stitches) might enhance recruitment and adherence of endogenous stem cells to the site of the lesion, thereby promoting in situ meniscal regeneration and chondroprotective functions. Study Design: Controlled laboratory study. Methods: Synovial fluid–derived mesenchymal stem cells (SMSCs) were identified and isolated from the knees of rabbits with a meniscal injury of 4 weeks’ duration. An in vitro analysis of adherence and chemotaxis of SMSCs was performed. For the in vivo assay, rabbits (n = 120) with meniscal lesions were divided into 3 groups: repair with high-purity magnesium stitches (Mg group), repair with absorbable sutures (Control group), and no repair (Blank group). Healing of the regenerated tissue and degeneration of the articular cartilage were evaluated by gross and histological analysis at postoperative weeks 1, 3, 6, and 12. The mechanical properties of the repaired meniscus were also analyzed (tensile testing). Results: In vitro, magnesium promoted the adhesion and migration of SMSCs, which were identified and increased in the knee joints with meniscal lesions. Moreover, fibrochondrogenesis of SMSCs was stimulated by magnesium. Compared with the other groups, the Mg group had enhanced tissue regeneration, lower cartilage degeneration, and retained mechanical strength at 12 weeks after meniscal repair. Conclusion/Clinical Relevance: Magnesium could be used for in situ meniscal repair due to the potential capacity of magnesium to recruit endogenous stem cells and promote synthesis of fibrocartilaginous matrix.

scholarly journals CALPAIN ACTIVITY UNDER EXPERIMENTAL INCREASING OF DOPAMINE LEVEL

2019 ◽  
Vol 19 (1S) ◽  
pp. 221-222
Author(s):  
N S Pestereva ◽  
A Z Marshak ◽  
M N Karpenko
Keyword(s):  
Control Group ◽  
Dopamine Level ◽  
Calpain Activity ◽  
In Situ Study ◽  
Calpain 2 ◽  
Casein Zymography ◽  
Experimental Group

The aim of our study was to identify the activity of calpains under conditions of an experimental increase in the level of dopamine. The work was performed at three levels: in vivo, in situ, in vitro. An in situ study was carried on a model of isolated nerve endings - synaptosomes. Using casein zymography in solution with FITC-casein, it was shown that incubation of synaptosomes dopamine leads to calpains secretion into the synaptosomal medium. The dopamine ability to directly activate calpain was demonstrated by casein zymography in a gel. Incubation in an activation buffer containing dopamine instead of the classical activator, calcium chloride, led to the activation of calpain-2. An in vivo experiment was performed on Wistar rats. The experimental group was orally administered the drug L-dopa (100 mg/kg), the control group - saline was injected in the same way.

Correlated Studies of Cellular Interactions Using TEM, Freeze Etching, and SEM

1974 ◽  
Vol 32 ◽  
pp. 320-321
Author(s):  
J. P. Revel
Keyword(s):  
Developmental Stages ◽  
Three Dimensional ◽  
Cell Movement ◽  
Cellular Interactions ◽  
Serial Sections ◽  
Cell Sheets ◽  
Freeze Etching ◽  
Early Developmental

Movement of individual cells or of cell sheets and complex patterns of folding play a prominent role in the early developmental stages of the embryo. Our understanding of these processes is based on three- dimensional reconstructions laboriously prepared from serial sections, and from autoradiographic and other studies. Many concepts have also evolved from extrapolation of investigations of cell movement carried out in vitro. The scanning electron microscope now allows us to examine some of these events in situ. It is possible to prepare dissections of embryos and even of tissues of adult animals which reveal existing relationships between various structures more readily than used to be possible vithout an SEM.

In vitro and in vivo polysaccharides assembly: ultrastructural and cytochemical study of growing plant cell wall components.

1978 ◽  
Vol 36 (2) ◽  
pp. 434-435
Author(s):  
D. Reis ◽  
B. Vian ◽  
J. C. Roland
Keyword(s):  
Cell Wall ◽  
Self Assembly ◽  
Plant Cell Wall ◽  
Higher Plants ◽  
Three Dimensional ◽  
Cytochemical Study ◽  
Wall Components

Wall morphogenesis in higher plants is a problem still open to controversy. Until now the possibility of a transmembrane control and the involvement of microtubules were mostly envisaged. Self-assembly processes have been observed in the case of walls of Chlamydomonas and bacteria. Spontaneous gelling interactions between xanthan and galactomannan from Ceratonia have been analyzed very recently. The present work provides indications that some processes of spontaneous aggregation could occur in higher plants during the formation and expansion of cell wall.Observations were performed on hypocotyl of mung bean (Phaseolus aureus) for which growth characteristics and wall composition have been previously defined.In situ, the walls of actively growing cells (primary walls) show an ordered three-dimensional organization (fig. 1). The wall is typically polylamellate with multifibrillar layers alternately transverse and longitudinal. Between these layers intermediate strata exist in which the orientation of microfibrils progressively rotates. Thus a progressive change in the morphogenetic activity occurs.

In Situ Localization of PPAR Gamma and Uncoupling Protein in Mouse Embryo Sections Using Digoxigenin-Labeled Riboprobes

1996 ◽  
Vol 54 ◽  
pp. 32-33
Author(s):  
C. Jennermann ◽  
S. A. Kliewer ◽  
D. C. Morris
Keyword(s):  
Alkaline Phosphatase ◽  
Room Temperature ◽  
Uncoupling Protein ◽  
Ppar Gamma ◽  
Nuclear Hormone Receptor ◽  
Full Length ◽  
Northern Analysis ◽  
Peroxisome Proliferator

Peroxisome proliferator-activated receptor gamma (PPARg) is a member of the nuclear hormone receptor superfamily and has been shown in vitro to regulate genes involved in lipid metabolism and adipocyte differentiation. By Northern analysis, we and other researchers have shown that expression of this receptor predominates in adipose tissue in adult mice, and appears first in whole-embryo mRNA at 13.5 days postconception. In situ hybridization was used to find out in which developing tissues PPARg is specifically expressed.Digoxigenin-labeled riboprobes were generated using the Genius™ 4 RNA Labeling Kit from Boehringer Mannheim. Full length PPAR gamma, obtained by PCR from mouse liver cDNA, was inserted into pBluescript SK and used as template for the transcription reaction. Probes of average size 200 base pairs were made by partial alkaline hydrolysis of the full length transcripts. The in situ hybridization assays were performed as described previously with some modifications. Frozen sections (10 μm thick) of day 18 mouse embryos were cut, fixed with 4% paraformaldehyde and acetylated with 0.25% acetic anhydride in 1.0M triethanolamine buffer. The sections were incubated for 2 hours at room temperature in pre-hybridization buffer, and were then hybridized with a probe concentration of 200μg per ml at 70° C, overnight in a humidified chamber. Following stringent washes in SSC buffers, the immunological detection steps were performed at room temperature. The alkaline phosphatase labeled, anti-digoxigenin antibody and detection buffers were purchased from Boehringer Mannheim. The sections were treated with a blocking buffer for one hour and incubated with antibody solution at a 1:5000 dilution for 2 hours, both at room temperature. Colored precipitate was formed by exposure to the alkaline phosphatase substrate nitrobluetetrazoliumchloride/ bromo-chloroindlylphosphate.

In-vitro- und In-vivo-Wirkung von Schilddrüsenhormon auf das Wachstum von Neuroblastomzellen

1990 ◽  
Vol 29 (03) ◽  
pp. 120-124
Author(s):  
R. P. Baum ◽  
E. Rohrbach ◽  
G. Hör ◽  
B. Kornhuber ◽  
E. Busse
Keyword(s):  
Cell Differentiation ◽  
Neuroblastoma Cells ◽  
Control Group ◽  
Initial Value ◽  
Initial Rise ◽  
Biphasic Effect ◽  
Contrast Microscopy ◽  
Morphological Sign

The effect of triiodothyronine (T3) on the differentiation of cultured neuroblastoma (NB) cells was studied after 9 days of treatment with a dose of 10-4 M/106 cells per day. Using phase contrast microscopy, 30-50% of NB cells showed formation of neurites as a morphological sign of cellular differentiation. The initial rise of the mitosis rate was followed by a plateau. Changes in cyclic nucleotide content, in the triphosphates and in the activity of the enzyme ornithine decarboxylase (ODC) were assessed in 2 human and 2 murine cell lines to serve as biochemical parameters of the cell differentiation induced by T3. Whereas the cAMP level increased significantly (3 to 7 fold compared with its initial value), the cGMP value dropped to 30 to 50% of that of the control group. ATP and GTP increased about 200%, the ODC showed a decrease of about 50%. The present studies show a biphasic effect of T3 on neuroblastoma cells: the initial rise of mitotic activity is followed by increased cell differentiation starting from day 4 of the treatment.

Anamnestic factors that shape reproductive health of women with repeated unsuccessful popygamy in vitro fertilization

2016 ◽  
pp. 140-143
Author(s):  
N.V. Cotsabin ◽  
◽  
O.M. Makarchuk ◽  
Keyword(s):  
High Risk ◽  
Risk Group ◽  
Polycystic Ovary ◽  
High Risk Group ◽  
Stress Factors ◽  
Control Group ◽  
Fertilization In Vitro ◽  
Infertile Women ◽  
Group I

The proportion of patients with multiple unsuccessful attempts of assisted reproductive technology (ART) is about 30% of all patients treated with the use of ART. Women with history of unsuccessful ART attempts - a special category of patients who require emergency attention and a thorough examination at the stage of preparation for superovulation stimulation,the selection of embryos and endometrium preparation for embryo transfer. The objective: to distinguish high-risk group of unsuccessful attempts based on a detailed analysis of anamnestic and clinical data of infertile women with repeated unsuccessful ART attempts that requires more in-depth study of hormonal features, ovarian reserve and condition of the endometrium. Materials and methods. For better understanding of the problem of repeated unsuccessful ART attempts and сreation of efficient infertility treatment algorithms for these couples we conducted a thorough analysis of anamnestic data of three groups of infertile women (105 patients), which were distributed by age: group I – younger than 35, the II group – from 35 to 40, the III group - over 40 years. These groups of patients were compared with each other and with the control group of healthy women (30 persons). Results. Leading stress factors in the percentage three times prevailed in the group of infertile women and had a direct connection with the fact of procedure «fertilization in vitro» and chronic stressors caused by prolonged infertility. Primary infertility was observed significantly more frequent in patients younger than 35 years (p <0.05), secondary infertility - mostly in the second and third experimental groups (p <0.05). Noteworthy significant percentage of wellknown causes of infertility and idiopathic factor in all groups, and the prevalence of tubal-peritoneal factor in the second and third experimental groups, and endocrine dysfunction in the I experimental group. The most common disorder among this category of woman was polycystic ovary syndrome. Frequency of usual miscarriage among patients of I ana II groups was two times higher than in the third group (p <0.05). Among the experimental groups the leading place belongs urinary tract infection, respiratory tract diseases, pathologies of the cardiovascular system. Data of the stratified analysis show an increase likelihood of repeated unsuccessful ART attempts under the influence of constant chronic stress (odds ratio OR=2.06; 95% CI: 0.95–3.17; p<0.05). Conclusions. Among infertile patients with repeated unsuccessful ART attempts must be separated a high risk group of failures. The identity depends on the duration of infertility, female age and leading combination of factors. Key words: repeated unsuccessful ART attempts, anamnesis, infertility, high risk.

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