A zigzag mode of application effectively lowered IOP in glaucoma patients at 6 months with a low incidence of complications despite the longer application time. Comparative studies to assess the ...potential advantages of treating a larger area of ciliary body with this approach are needed.
The purpose of this study is to evaluate the clinical outcome of micropulse transscleral laser cyclophotocoagulation with zigzag mode of application in adult glaucomatous patients.
A prospective single-arm clinical trial included a series of 34 eyes of 30 consecutive patients who underwent micropulse transscleral cyclophotocoagulation (MP-TSCPC) with zigzag technique at a private ophthalmology center. The trial was conducted from March 16, 2021 to April 12, 2021. Patients who had at least 6 months of follow-up were included. MP-TSCPC probe was moved for 2 mm perpendicular to a line 3 mm parallel to the cornea. This aims to cover the largest circumference of the area supposed to hinder the cilliary body. The probe is moved over 3 quadrants for 90 seconds for each quadrant (total 270 s). Defined as an intraocular pressure (IOP) of 6 to 21 mm Hg or a reduction of IOP by 30%. Failure was defined as an inability to meet the criteria for success or need for retreatment.
The mean age of involved patients was 52.9 (±SD: 3.9) years old. The mean IOP before MP-TSCPC was 37.47 (±SD: 11.08) mm Hg, which was significantly reduced to 17.7 (±SD: 7.4) mm Hg in the last follow-up visit at 6 months. Number of medications showed significant reduction from mean 3.44 (±SD: 0.99) to 1.91 (±SD: 1.26) in the last follow-up. Success rate was found to be 88% (30 out of 34 eyes) at the final follow-up, where 9 cases showed complete success (26.5%), whereas 21 (61.8%) cases showed qualified success. Despite the relatively higher parameters used in our study, no cases reported postoperative complications apart from only 1 case of reduced visual acuity by 1 line.
A zigzag mode of application effectively lowered IOP in glaucoma patients at 6 months with a low incidence of complications despite the longer application time. Comparative studies to assess the potential advantages of treating a larger area of ciliary body with this approach are needed.
Aim The aim of this study was to compare mechanical photorefractive keratectomy (PRK) to transepithelial photorefractive keratectomy (tPRK), used to correct mild and moderate myopia, with respect to ...the epithelial thickness mapping (ETM). Setting The study was carried out at Al-Mashreq Eye Center, Cairo, Egypt. Patients and methods This is a prospective comparative study that was carried out on 20 myopic patients (40 eyes), with spherical equivalent (SE) ranging from −1.0 to −5.0 D. The cases were divided into two groups: group A included the right eyes (OD) of all patients, and group B included the left eyes (OS). Group A underwent mechanical PRK using ‘hockey stick’ and excimer laser, using Mel-90 excimer laser with 250 Hz mode, and 0.7-mm spot scanning. Group B underwent tPRK using Mel-90 (8-mm lamellar ablation for 55 μm, 250 Hz). Uncorrected visual acuity (UCVA), manifest refraction, and ETM using AngioVue spectral domain optical coherence tomography systems were performed. The ETM was measured preoperatively and at 1 week, 1 month, and 3 months postoperatively. In addition, postoperative pain was assessed. Results The median preoperative UCVA was 0.3 (range, 0.2–0.4) in both eyes (OU), whereas the median preoperative best-corrected visual acuity was 1 (range, 0.8–1). There was a statistically significant increase in UCVA across the postoperative period in both groups (P<0.001). The median UCVA improved to 0.5 (OU) after 1 week, and to 0.9 (OD) and 1.0 (OS) after 1 month and remained almost the same at 3 months postoperatively. There was a statistically significant decrease in SE at all points of the follow-up period in both groups (P<0.001). A slight change in SE was observed between the first and third month postoperatively in both groups, which was statistically insignificant. Patients reported postoperative pain on the first postoperative day, which was more in the tPRK group. There was a statistically significant change in epithelial thickness across the study period in both groups (P<0.001). The ETM showed a faster epithelial regeneration in group B, which was statistically significant at 1 week postoperatively (P=0.004). The epithelial thickness continued to increase in both groups to reach almost the preoperative value at the third month postoperatively. All cases that showed postoperative haze were less than grade 1.0 (Hanna’s scale). Conclusion Mechanical PRK and tPRK provided very similar results 3 months postoperatively. Both procedures were predictable, effective, and safe. The patients reported postoperative pain on the first postoperative day that was more in the tPRK group. The tPRK group expressed a faster epithelial regeneration than the PRK group at 1 week postoperatively. However, at 3 months postoperatively, the corneal epithelium reached an almost normal thickness in both groups. Visual recovery was noted to be faster in the tPRK group.
Single-kenaf fiber-reinforced polymer composites are typically characterized by relatively low strength and stiffness properties that make them unsuitable for structural applications. However, they ...are lightweight, economical, and ecofriendly. This paper presents a study on the manufacturing and mechanical characterization of bidirectional kenaf (K) fiber-reinforced epoxy composites hybridized with carbon (C) fibers in various stacking sequences and the effects of hybridization on salient physical and mechanical properties. Single and hybrid fiber composites were fabricated utilizing the vacuum infusion molding technique. The density, tensile, flexural, and interlaminar shear properties in hybrid composites increased significantly when carbon fiber volume increased from 9% to 16%. Stacking sequences in a hybrid affected the mechanical properties of the composites. The highest tensile strength and modulus were shown by the seven-layer hybrid composite with an alternate K/C stacking sequence and C layers as skin layers, i.e., C/K/C/K/C/K/C, among all tested hybrid composites. Sandwich design in the hybrid (C2/K3/C2) had higher flexural strength (+300%), flexural modulus (+414%), interlaminar shear strength (+278%), lower water absorption (−46%), and thickness swelling (−30%) compared to single-fiber kenaf/epoxy composites. Density increased by 5% in hybrid composites. The highest fracture toughness (+134%) was achieved using the dual sandwich design structure hybrid (C/K2/C2/K2/C). The developed composite has applications in stairways, walkways, and bridges.
Eugene O’Neill’s The Emperor Jones (1920) is the first ever projection of a black protagonist on Broadway who carries the imprints of white ideals. While the playwright presents the title character ...Brutus Jones as a kleptocrat, he seems to corroborate the fact that the streetwise black Jones’ growing up in New York has a lot to do with his rule as a despot on the island. This paper explores O’Neill’s projection of the American mercantile psyche as seen on the island’s experience of colonial capitalism and the enactment of original sin in America by a journey through Brutus’ personal and racial memory lanes. This article also investigates to what extent Jones is a by-product of the American capitalist system which considers greed as good and money as the bottom line of success.
Visual outcome of implantable phakic contact lens Mostafa, Mohamed; El-Shayeb, Ashraf; El-Shahed, Ahmed
Journal of Egyptian ophthalmological society,
07/2022, Letnik:
115, Številka:
3
Journal Article
Recenzirano
Odprti dostop
Aim To evaluate the visual outcome of implantable phakic contact lens (IPCL) in high myopia.
Setting Al-Mashreq Eye Center, Cairo, Egypt.
Patients and methods Thirty eyes of 17 patients underwent ...surgery to correct high myopia using IPCL (Care Group-India) with a central hole (V2.0). Visual acuity, spherical equivalent, and intraocular pressure (IOP) were evaluated 6 months postoperatively. Anterior chamber parameters Anterior chamber volume (ACV), Anterior chamber depth (ACD), Anterior chamber angle width (ACAW) were measured using Pentacam.
Results After 6 months, spherical equivalent decreased from −14.19±4.2 to −0.18±0.66 D, all cases were within ±1.00 D of intended correction. Best corrected visual acuity (BCVA) remained unchanged in 13% of cases, 13% gained one line, and 74% gained two or more lines. ACV, ACD, and ACAW decreased from 189.77±20.19 mm3, 3.15±0.27 mm, and 37.31±5.63° to 131.4±14.01 mm3, 3.05±0.29 mm, and 23.94±4.81°, respectively. Changes in IOP between preoperative and 6 months postoperatively were statistically insignificant.
Conclusion IPCL is a safe, effective, and predictable surgery to correct high myopia. Most cases gained one or more lines of BCVA. Reduction of ACV did not induce IOP rise during 6 months of follow-up.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Purpose To evaluate changes that occur in foveal avascular zone (FAZ) in diabetic hypertensive patients by optical coherence tomography angiography (OCTA).
Patients and methods OCTA was performed for ...60 eyes of 35 diabetic hypertensive patients. This study was done in Benha University Hospital between February and June 2021. FAZ area was measured by a frame that was centered around it. Moreover, the vessel density was measured also by detecting the superficial vessel density (SVD) and the deep vessel density (DVD).
Results In diabetic hypertensive (60 eyes of 35 patients) with average age 55.52 (±6.88) years and mean duration of the disease 12.17 (±7.15) years, the mean value of the FAZ was 0.37 (±0.54) mm, denoting enlargement of the FAZ diameter. In addition, the vessel density showed that there is decreasing in the SVD (43.9±5.89) and it was correlated to the best-corrected visual acuity and age of the patients (P<0.05), while it was highly correlated to the DVD (P<0.001). On the other hand, there was a decrease in DVD with a mean of 43.17±7.44, which was statistically significant with the age of the patients (P<0.05), but there was no significant relationship with duration of the disease, glycated hemoglobin, and best-corrected visual acuity.
Conclusion OCTA is a noninvasive technique to image the retinal and choroidal vasculature. The study concluded that diabetic retinopathy in the presence of systemic hypertension leads to increasing of the FAZ area. Moreover, it leads to decreasing in both the SVD and DVD. Also, it allows for early detection and easy follow-up of the disease.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
This study investigated the effects of wolframite on the fire resistance and adhesion strength of intumescent fire‐retardant coating (IFRC) using a siloxane‐modified epoxy binder. The modification of ...bisphenol A epoxy was confirmed via Hydrogen‐Nuclear Magnetic Resonance Analysis. The IFRC samples were developed with wolframite (0.25–2.0 wt%) and evaluated for Thermogravimetric analysis (TGA), fire resistance test, furnace fire test for char expansion, morphology and chemical composition, adhesion test and water immersion test. This study identified a coating formulation containing 2.0 wt% of wolframite that showed 57.2% improvement in the residual weight, substrate temperature of 176.7°C and produced a compact char. Field Emission Scanning Electron Microscopy showed that the addition of wolframite reduced pore size thereby increasing the char strength. X‐ray diffraction identified iron neodymium compounds in the char layers, which lowered the pore size resulting in lower substrate temperature. X‐ray photoelectron spectroscopy indicated that the antioxidant capability and the carbon content were increased by 6.9% and 50.3% respectively. The adhesion strength was reduced, however, was within the industrial standards of 2.07 MPa. The water immersion test showed a maximum 66.7% reduction (WF2.0) in the water permeation through the coating.
Zinc (Zn
2+
) is an essential micronutrient and the second most abundant trace metal in the human body. The important role that Zn
2+
plays in hemostasis is exemplified by platelet-related bleeding ...phenotypes coinciding with dietary Zn
2+
deficiency. These phenotypes are rectified upon Zn
2+
supplementation. Labile (unbound) Zn
2+
is present in the plasma at micromolar levels, but is also detected in atherosclerotic plaques, and released from platelet α granules. Therefore, it is likely that localized Zn
2+
concentrations are higher at sites of thrombosis and hemostasis. Exogenous Zn
2+
is a regulator of the hemostatic responses, with roles during coagulation and platelet activation. Extracellular Zn
2+
gains access to the platelet cytosol and induces full platelet activation at high concentrations, and potentiates platelets to activation by conventional agonists at lower concentrations. Zn
2+
-induced platelet activation is dependent on PKC and integrin α
IIb
β
3
, and is associated with tyrosine phosphorylation of platelet proteins. Agonist evoked platelet activation results in intracellular Zn
2+
(Zn
2+
i
) fluctuations that are sensitive to the platelet redox state. Increases in Zn
2+
i
correlate with activation responses, including shape change, granule release, α
IIb
β
3
activation and phosphatidyl-serine exposure, consistent with a role as a second messenger. This review provides insight into the numerous demonstrated and potential roles for Zn
2+
in platelet function during thrombosis and hemostasis, highlighting its increasing acceptance as an intracellular and extracellular platelet regulatory agent.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
•Higher degradation rates and strong antibacterial action induce cytotoxicity.•Copper ions kill metal-resistant bacteria by electron extraction from their cell.•Silver ions bond with the thiol group ...and destroy the bacteria's cell wall.•Gallium ions cause malnutrition of bacteria by blocking iron absorption.•Alkali elements and oxidative states +1 and +2 show strong antibacterial property.
Benefits achieved by the biodegradable magnesium (Mg) and zinc (Zn) implants could be suppressed due to the invasion of infectious microbial, common bacteria, and fungi. Postoperative medications and the antibacterial properties of pure Mg and Zn are insufficient against biofilm and antibiotic-resistant bacteria, bringing osteomyelitis, necrosis, and even death. This study evaluates the antibacterial performance of biodegradable Mg and Zn alloys of different reinforcements, including silver (Ag), copper (Cu), lithium (Li), and gallium (Ga). Copper ions (Cu2+) can eradicate biofilms and antibiotic-resistant bacteria by extracting electrons from the cellular structure. Silver ion (Ag+) kills bacteria by creating bonds with the thiol group. Gallium ion (Ga3+) inhibits ferric ion (Fe3+) absorption, leading to nutrient deficiency and bacterial death. Nanoparticles and reactive oxygen species (ROS) can penetrate bacteria cell walls directly, develop bonds with receptors, and damage nucleotides. Antibacterial action depends on the alkali nature of metal ions and their degradation rate, which often causes cytotoxicity in living cells. Therefore, this review emphasizes the insight into degradation rate, antibacterial mechanism, and their consequent cytotoxicity and observes the correlation between antibacterial performance and oxidation number of metal ions.
A 316L stainless steel (SS) alloy was developed with 1, 3, and 5 vol% titanium (Ti) reinforcement using the powder injection molding route, representing a low-cost option for biomedical implants. The ...investigation encompassed 1300 °C, 1350 °C, and 1380 °C sintering temperatures to ascertain the optimal physical and mechanical properties. Both sintering temperature and Ti influenced sintered density, and Ti mitigated the deleterious effects of residual carbon. At higher sintering temperatures, carbon and silicon tended to migrate and accumulate at the brink of Ti, leading to the formation of intermetallic compounds and increased brittleness. Dispersed Ti particles within the 316L matrix acted as nucleation sites and enhanced solid solubility with improved density. An astounding 96.11 % sintered density was achieved at 3 vol% Ti sample sintered at 1380 °C. During the tensile test, 5 vol% Ti at 1380 °C exhibited a low modulus of 58.9 GPa, which is highly desirable for orthopedic implant application. The XRD, SEM, tensile test, and nano-indentation results collectively provide evidence of beta-titanium formation during the sintering process. Conversely, the sample incorporating 3 vol% titanium, sintered at 1380 °C, demonstrated a balanced performance, showcasing 432.94 ± 12.8 MPa ultimate tensile strength, 3.06 ± 0.17 % elongation, 74.2 GPa modulus, and 322 MPa and 423 MPa 0.2 % offset flexural and compressive yield strengths, respectively. Notably, an improvised wear resistance test underscored its aptitude for sliding wear resistance, solidifying its potential as a promising candidate for biomedical implants.
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