scholarly journals Comparative Study of Corneal Endothelial Cell Damage after Femtosecond Laser Assisted Deep Stromal Dissection

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Ting Liu ◽  
Jingjing Zhang ◽  
Dapeng Sun ◽  
Wenjie Sui ◽  
Yangyang Zhang ◽  
...  
Keyword(s):  
Femtosecond Laser ◽  
Cell Damage ◽  
Endothelial Damage ◽  
Lamellar Keratoplasty ◽  
Control Group ◽  
Electron Microscopic ◽  
Anterior Lamellar Keratoplasty ◽  
Bed Thickness ◽  
Scanning Electron

Purpose.To find a relatively safe designed stromal bed thickness to avoid endothelial damage for lamellar keratoplasty with an Allegretto Wavelight FS200 femtosecond laser.Methods.Twelve rabbits were randomly divided into 50 μm and 150 μm groups according to the anticipated residue stromal bed thickness preparation with a femtosecond laser. Six rabbits without laser cutting were used as a control group. Central endothelial images were analyzed with in vivo confocal microscopy and scanning electron microscopy. The apoptosis of endothelium was evaluated with Hoechst 33342 staining and a TUNEL assay.Results.The endothelium of the 50 μm group had extensive injuries upon in vivo confocal and scanning electron microscopic observation, and minor injuries were observed in the 150 μm group. Moreover, more apoptotic cells were observed in the 50 μm group.Conclusions.When using a FS200 femtosecond laser assisted anterior lamellar keratoplasty, there was minor endothelium damage with a 150 μm stromal bed, and a more than 150 μm thickness stromal bed design may prevent the damage of corneal endothelium.

Haemostatic Clot Formation at Anastomosis of Synthetic Venous Graft in Defibrinogenated Dogs: A Scanning Electron Microscopic Study

1981 ◽  
Vol 45 (03) ◽  
pp. 276-281 ◽  
Author(s):  
S Ishimaru ◽  
E Berglin ◽  
H-A Hansson ◽  
A-C Teger-Nilsson ◽  
G William-Olsson
Keyword(s):  
Vena Cava ◽  
Treated Group ◽  
Control Group ◽  
Electron Microscopic ◽  
Scanning Electron Microscopic Study ◽  
Fibrin Network ◽  
Scanning Electron Microscopic ◽  
Expanded Polytetrafluoroethylene Graft ◽  
Morphological Differences ◽  
Scanning Electron

SummaryA segment of the inferior vena cava was replaced by an expanded polytetrafluoroethylene graft in 13 dogs. Five of them served as a control group, while the other 8 were moderately or severely defibrinogenated with subcutaneous batroxobin. Plasma fibrinogen decreased to extremely low values throughout the experiment in the defibrinogenated dogs except in the moderately treated group in which it temporarily rose to 0.72-0.87 g/1 on the first postoperative day.Scanning electron microscopic observations of the haemostatic clot formed at the anastomoses of the graft revealed no significant morphological differences in platelet adhesion and/or aggregation between the three groups. These findings confirmed that platelets play a key role in primary haemostasis during defibrinogenation.The fibrin network was slightly diminished and only short fibrin filaments could be seen in the moderately and severely defibrinogenated groups respectively. These differences in composition of the clots are discussed in relation to their haemostatic capacity.

An Electron Microscopic Study of Platelet Thrombus Formation in the Rabbit with Particular Regard to 5-Hydroxytryptamine Release

1967 ◽  
Vol 18 (03/04) ◽  
pp. 592-604 ◽  
Author(s):  
H. R Baumgartner ◽  
J. P Tranzer ◽  
A Studer
Keyword(s):  
Endothelial Cells ◽  
Endothelial Cell ◽  
Vessel Wall ◽  
Thrombus Formation ◽  
Endothelial Damage ◽  
Electron Microscopic ◽  
Rabbit Ear ◽  
Basement Lamina ◽  
Platelet Thrombus

SummaryElectron microscopic and histologic examination of rabbit ear vein segments 4 and 30 min after slight endothelial damage have yielded the following findings :1. Platelets do not adhere to damaged endothelial cells.2. If the vessel wall is denuded of the whole endothelial cell, platelets adhere to the intimai basement lamina as do endothelial cells.3. The distance between adherent platelets as well as endothelial cells and intimai basement lamina measures 10 to 20 mµ, whereas the distance between aggregated platelets is 30 to 60 mµ.4. 5-hydroxytryptamine (5-HT) is released from platelets during viscous metamorphosis at least in part as 5-HT organelles.It should be noted that the presence of collagen fibers is not necessary for platelet thrombus formation in vivo.

Protective Effect of Boswellic Resin Against Memory Loss and Alzheimer’s Induced by Aluminum Tetrachloride and D-Galactose (Experimental study in Mice)

2020 ◽  
Author(s):  
K. Zerrouki ◽  
N. Djebli ◽  
L. Gadouche ◽  
I. Erdogan Orhan ◽  
F. SezerSenol Deniz ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Protective Effect ◽  
Cell Damage ◽  
Memory Loss ◽  
Control Group ◽  
Total Extract ◽  
Swiss Mice ◽  
Octyl Acetate

Nowadays, because of the industrialization, a lot of contaminant were available ; the consequences of this availability are apparition of diseases including neurodegeneration. Neurodegenerative diseases of the human brain comprise a variety of disorders that affect an increasing percentage of the population. This study is based on the effect of the Boswellic resin, which is from a medicinal plant and known for its antioxidant effects on nerve cell damage. The objective of this work was to evaluate the in vitro and in vivo effects of the Boswellic resin on anticholinesterase activity and Alzheimer’s disease (AD) induced by D-galactose and aluminum tetrachloride in Swiss mice. Chemical composition of the resin essential oil was identified by the CG-MS analysis. The antioxidant activity was also assessed by the DMPD and metal chelation methods. In order to understand the mechanism of memory improvement, the acetylcholinesterase, AChE, and butyrylcholinesterase, BChE, inhibitory assays were performed. In vivo part of the study was achieved on Swiss mice divided into four groups: control, AD model, treated AD, and treated control group. The identification of chemical composition by CG-MS reach the 89.67% of the total extract compounds presented some very important molecules (p-Cymene, n-Octyl acetate, α-Pinene…). The present study proves that Boswellic resin improves memory and learning in treated Alzheimer’s group, modulates the oxidative stress and be involved in the protective effect against amyloid deposition and neurodegeneration, and stimulates the immune system in mice’s brain.

Experimental rationale for using a viscoprotection of the corneal endothelium on the graft formed with a femtosecond laser for the descemet stripping endothelial keratoplasty

2021 ◽  
pp. 94-96
Author(s):  
I.S. Tkachenko ◽  
◽  
B.E. Malyugin ◽  
S.A. Borzenok ◽  
D.S. Ostrovskiy ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Femtosecond Laser ◽  
Corneal Endothelium ◽  
Hydroxypropyl Methylcellulose ◽  
Lamellar Keratoplasty ◽  
Confocal Laser ◽  
Control Group ◽  
Endothelial Keratoplasty ◽  
Descemet Stripping Endothelial Keratoplasty ◽  
Experimental Group

Purpose. To rationale experimentally the use of a viscoprotection of the corneal endothelium on the graft formed with a femtosecond laser for the descemet stripping endothelial keratoplasty. Material and methods. In our study, we used 12 pig's corneoscleral discs. The preservation time before the experiment averaged 12±4 hours. The corneas were divided into 2 groups. In the operating room, the graft was formed using an LDV Z8 femtosecond laser (Ziemer, Switzerland) from the endothelial side. Before applanation of the donor cornea and femtolaser head, a 1% solution of hydroxypropyl methylcellulose (HPMC) was applied to the endothelium - experimental group. The control group was appraised according to the standard technique, with the application of a few drops of a solution for storing the corneas. Then the applanation was monitored and evaluated by laser optical coherence tomography. Then the graft was separated from the bed and transferred to a conservation medium. Under laboratory conditions, to determine the viability of endothelial cells, the graft was stained with a «vital» dye with the commercial name Life and Dead (Abcam, UK) and placed in a confocal laser scanning microscope. Endothelial cells were counted using the ImageJ software. Results. In the experimental and control groups, the number of living endothelial cells (EC) was 91.06±1.49% and 83.86±2.14%, respectively (p<0.001). The number of dead ECs in the control group was 7.2±0.65% more than in the experimental group and amounted to 16.14±2.14% and 8.94±1.49%, respectively (p<0.001). Conclusion. The study demonstrated that the use of viscoprotection of the corneal graft endothelium for posterior lamellar keratoplasty is quite effective, and significantly reduces the loss of EC at the stage of cutting out the graft with a femtosecond laser. Key words: descemet stripping endothelial keratoplasty, femtosecond laser, vital dyes.

scholarly journals Femtosecond laser-assisted anterior lamellar keratoplasty (FSALK) versus microkeratome-assisted anterior lamellar keratoplasty (MALK) for the treatment of anterior corneal dystrophy.

2016 ◽  
Vol 15 (2) ◽  
Author(s):  
Radwan Almousa ◽  
Sheraz M Daya
Keyword(s):  
Visual Acuity ◽  
Femtosecond Laser ◽  
Visual Outcome ◽  
Corneal Dystrophy ◽  
Lamellar Keratoplasty ◽  
Secondary Outcome ◽  
Clinical Recurrence ◽  
Corneal Scarring ◽  
Anterior Lamellar Keratoplasty

Purpose: To compare the visual outcome of femtosecond laser-assisted anterior keratoplasty (FSALK) and microkeratome-assisted anterior lamellar keratoplasty (MALK) in anterior corneal dystrophy.  Methods: retrospective comparative chart review of 7 eyes that underwent FSALK and 7 eyes that underwent MALK. The primary outcome was the visual outcome of both procedures. The secondary outcome was the recurrence of the corneal dystrophies.Results: Mean follow-up time was 30±14(7-51) months for the FSALK group and 127±28(80-127) months for the MALK group. In the FSALK group the preoperative best spectacle-corrected visual acuity (BSCVA) improved from 20/63 to 20/25 at 36 months. In the MALK group there was 1 eye with documented BSCVA over 36 months follow-up; it improved from 20/160 preoperatively to 20/32 at 36 months. Uncorrected visual acuity (UCVA) at 36 months improved from 20/100 preoperatively to 20/63 in the FSALK group and from 20/200 preoperatively to 20/63 in the MALK group. Five eyes with Reis-Bucklers showed a clinical recurrence at a mean of 142±13(125-152) months. Two eyes with granular dystrophy showed a clinical recurrence at 23 and 80 months of follow-up. One eye in the MALK group had epithelial ingrowth. One eye in the FSALK group with compromised ocular surface due to 2 previous penetrating keratoplasty, suffered bacterial keratitis that ended up with corneal scarring. Conclusion: Both procedures improve visual outcome for anterior corneal dystrophy. FSALK has theoretical advantages over MALK; however, larger prospective studies are needed to prove this.

scholarly journals Scanning electron microscopic examination of enamel surface after fixed orthodontic treatment: In-vivo study

2012 ◽  
Vol 140 (1-2) ◽  
pp. 22-28 ◽  
Author(s):  
Tijana Sessa ◽  
Jelena Civovic ◽  
Tina Pajevic ◽  
Jovana Juloski ◽  
Milos Beloica ◽  
...  
Keyword(s):  
Electron Microscopic Examination ◽  
Surface Damage ◽  
Multivariate Regression Analysis ◽  
Enamel Surface ◽  
Orthodontic Appliances ◽  
Electron Microscopic ◽  
Fixed Orthodontic Appliances ◽  
Tooth Surfaces ◽  
Scanning Electron

Introduction. Therapy with fixed orthodontic appliances starts with bracket bonding and ends with debonding of brackets, leaving enamel surface varied. Objective. The aim of this pilot study was to examine enamel surface before and after debonding of orthodontic brackets by the use of scanning electron microscopy (SEM). Methods. Epoxy replicas of four patients? premolars indicated for therapy with fixed orthodontic appliances were made and brackets were bonded to their teeth with a different adhesives (Enlight, No-mix, Fuji Ortho LC and Heliosit Orthodontic) (n=4). Two months later, brackets on premolars were debonded and amounts of adhesive left on the tooth surfaces and the bracket bases were evaluated with the adhesive remnant index (ARI). After resin removal, epoxy replicas were made and the surface of premolars was evaluated with the enamel surface index (ESI). All replicas of premolars (n=32) were prepared for SEM examination and compared under different magnifications. Tooth damage was estimated based on correlation between ARItooth and ESI. Results. Pearson?s ?2 test showed no significant differences between ARItooth and ARIbracket of four materials used. Nonparametric correlations showed significant differences between ARItooth and ARIbracket, ESI and ARItooth, and between ESI and ARIbracket. Increasing of ARItooth is followed with the descent of ARIbracket and the ascent of ESI. Multivariate regression analysis showed a significant correlation between ESI and ARItooth. Conclusion. Most bond failures took place at enamel-adhesive interface. ARItooth was a predictor to enamel surface damage. The type of material did not affect enamel surface damage.

scholarly journals Scanning electron microscopic study of ovary and oviduct of crossbred dairy cows with ovarian hypoplasia

2021 ◽  
Vol 52 (2) ◽  
Author(s):  
V. R. Annie ◽  
K. M. Lucy ◽  
N. Ashok ◽  
S. Maya ◽  
Hiron M. Harshan ◽  
...  
Keyword(s):  
Dairy Cows ◽  
Ovarian Tissue ◽  
Control Group ◽  
Electron Microscopic ◽  
Scanning Electron Microscopic Study ◽  
Epithelial Cell Surface ◽  
Large Round ◽  
Livestock Productivity ◽  
The Right ◽  
Scanning Electron

Hypoplasia of ovary is one of the major causes of infertility in dairy cattle, which is characterized by absence of oestrus cycle, affecting livestock productivity and economics to a great extent. This study was conducted on the female genitalia collected from 100 dairy cows/heifers from the Meat Technology Unit, Mannuthy which included six animals culled on account of factors other than infertility with normal genitalia (control group) and remaining animals with a known history of infertility. Two animals of 22 months and 24 months of age showed bilateral ovarian hypoplasia. The history revealed that the animals were healthy, but had not shown oestrus. Grossly ovaries of the first animal appeared as pink-coloured, small, wrinkled, flattened, elongated structures without any follicles or CL. Second animal showed inactive, small, flat, streak-like left ovary without any cyclical structures. But the right ovary showed a single large corpus haemorrhagicum on the caudal end. Then ovarian tissue was fixed in 2 percent gluteraldehyde in 0.1 M phosphate buffer at pH 7.3. Under scanning electron microscopy, the ovary exhibited an uneven surface with clefts and grooves. The surface cells lost their normal appearance without any microvilli. Large round smooth germ cells were also observed on the ovarian surface. In the oviduct, the mucosa was lined by nonciliated cells having rounded surface interspersed among shrunken cells. The epithelial cell surface was covered with bulbous processes. Ciliated cells were not observed in the present study. Ovarian abnormality is reported to be the main cause of altered morphology of the surface epithelial cells and change in the ultrastructure of oviductal mucosa.

Cell interactions of Listeria monocytogenes L forms and peritoneal exudative cells in rats

1993 ◽  
Vol 39 (11) ◽  
pp. 1014-1021 ◽  
Author(s):  
L. Mihailova ◽  
N. Markova ◽  
T. Radoucheva ◽  
D. Veljanov ◽  
S. Radoevska
Keyword(s):  
Listeria Monocytogenes ◽  
Peritoneal Cavity ◽  
Electron Microscopic Examination ◽  
Lavage Fluid ◽  
Host Cells ◽  
Electron Microscopic ◽  
Cellular Defense ◽  
Scanning Electron Microscopic ◽  
Scanning Electron

Listeria monocytogenes 4b and its forms without cell walls (L forms of a protoplastic type) were used to study in vivo interactions with host cells. Samples of peritoneal lavage fluid were obtained from rats intraperitoneally inoculated at intervals between 1 and 15 days after challenge, for scanning electron microscopic, bacteriological, biochemical, and cytometrical investigations. Scanning electron microscopic examination revealed continuous adhesion of L forms on the macrophage surface up to 15 days after inoculation. The persistence of the L forms within the peritoneal cavity was also shown bacteriologically at all sample times, while the parental bacterial forms were isolated from the peritoneal cavity up to 7 days after challenge. The total count of peritoneal exudative cells determined by automated flow peroxidase cytometry peaked on the 15th day in animals infected with parental forms, while in animals infected with L forms the peak was lower and the macrophage population was predominant. The glycolytic and acid phosphatase activity of peritoneal exudative cells was two times higher in rats infected with L forms as compared with rats infected with the L. monocytogenes parental forms on the 3rd day after challenge. An understanding of the nature of the interactions between L forms of L. monocytogenes and peritoneal exudative cells found in vivo could be used to establish the influence of L forms on host cellular defense mechanisms.Key words: Listeria monocytogenes, L forms, peritoneal exudative cells, electron microscopy.

Femtosecond laser-assisted deep anterior lamellar keratoplasty: A safer option in keratoconus surgery

2021 ◽  
pp. 112067212110590
Author(s):  
Cristina Monterosso ◽  
Marco Antonini ◽  
Antonio Di Zazzo ◽  
Daniele Gaudenzi ◽  
Luigi Caretti ◽  
...  
Keyword(s):  
Visual Acuity ◽  
Femtosecond Laser ◽  
Lamellar Keratoplasty ◽  
Deep Anterior Lamellar Keratoplasty ◽  
Persistent Epithelial Defect ◽  
Corrected Visual Acuity ◽  
Anterior Lamellar Keratoplasty ◽  
Best Corrected Visual Acuity ◽  
Persistent Epithelial Defects

Purpose To evaluate postoperative safety of femtosecond laser deep anterior lamellar keratoplasty performed with an innovative anvil profile in keratoconus patients. Methods This is a single-center, retrospective cohort study. We reviewed medical records of 89 keratoconus patients that underwent femtosecond laser deep anterior lamellar keratoplasty surgery (46 eyes) and manual deep anterior lamellar keratoplasty (47 eyes). Inclusion criteria required: age > 18 years old, best-corrected visual acuity < 0.3 LogMAR, continuous suture of the graft, postoperative immunomodulant regimen with dexamethasone 0.1% for 6 months and at least 12 months follow-up. Previous eye surgery, hydrops, and other ocular disease were excluded. The main outcome measures were postoperative events: rejections, persistent epithelial defects, and graft failures. Results During the follow-up (20 ± 6 months) graft rejection was diagnosed in 0 of femtosecond laser deep anterior lamellar keratoplasty versus 6 (17%) of manual deep anterior lamellar keratoplasty [ p 0.027], persistent epithelial defect in 0 of femtosecond laser deep anterior lamellar keratoplasty versus in 4 (11%) of manual deep anterior lamellar keratoplasty [ p 0.048] and graft failure occurred in 4 (11%) of manual deep anterior lamellar keratoplasty. The best-corrected visual acuity, after removal of sutures, was better in the femtosecond laser deep anterior lamellar keratoplasty group 0.09 ± 0.08 LogMAR versus 0.16 ± 0.13 LogMAR in manual deep anterior lamellar keratoplasty [ p 0.035] group although refractive spherical equivalent and cylinder, topographic average keratometry and cylinder were similar. Conclusions Anvil-shaped femtosecond laser deep anterior lamellar keratoplasty in keratoconus surgery increases safety and readiness of recovery, decreasing the incidence of corneal rejection, epithelial defects, graft failures, and producing better best-corrected visual acuity after removal of sutures.

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