Markers characterizing corneal damage during aging of rat

Aging is a biological phenomenon that involves an increase of oxidative stress associated with gradual degradation of the structure and function of the cornea. Gender differences and subsequent deterioration of cornea is an interesting topic, especially yet few data are available concerning the impact of age, especially on the corneal. One hundred male and female Wistar albino rats ages 3, 6, 18, 24, and 30 months (n=10 equal for male and female) were used. At the time interval, cornea were investigated by light and transmission electron microscopy (TEM), immunohistochemistry of caspase 3 (casp3), glial fibrillar acidic protein(GFAP) and CD45 and  flow cytometry of DNA, bcl-2-like protein 4 (BAX), transforming growth factor beta (TGF-β) and Cd45 (lymphocyte common antigen). Light and TEM investigation  revealed apparent deterioration of atrophy of corneal epithelium with vesicular vacuolar degeneration, hyalinization of stromal collagen fibrils and swelling and degeneration of the endothelial lining the descemet's membrane. There was apparent loss of keratocytes within corneal stroma. Immunohistochemistry of casp 3 and CD45 were markedly increased manifesting cell damage. GFAP showed apparent reduction of innervation of corneal stroma and endothelium layer. Flow cytometry of DNA, Bax and TGF revealed increased apoptic cell death of cornea of 30M-old rats. We concluded that aging contributed to an apparent increase of cellular damage of different corneal region associated with alterations of cell markers

Insertion of a foldable hydrophobic IOL through the trabeculectomy fistula in cases with Microincision cataract surgery combined with trabeculectomy

BACKGROUND: The use of conventional foldable hydrophobic intraocular lenses (IOLs) in microincision cataract surgery (MICS) currently requires wound enlargement. We describe a combined surgical technique of MICS and trabeculectomy with insertion of a foldable IOL through the trabeculectomy fistula. METHODS: After completion of MICS through two side port incisions, a 3.2 mm keratome is used to enter the anterior chamber under the previously outlined scleral flap. An Acrysof multi piece IOL (Alcon labs, Fort Worth, Tx) is inserted into the capsular bag through this incision. The scleral flap is then elevated and a 2 × 2 mm fistula made with a Kelly's punch. The scleral flap and conjunctival closure is performed as usual. RESULTS: Five patients with primary open angle glaucoma with a visually significant cataract underwent the above mentioned procedure. An IOL was implated in the capsular bag in all cases with no intraperative complications. After surgery, all patients obtained a best corrected visual acuity of 20/20, IOL was well centered at 4 weeks follow up. The mean IOP (without any antiglaucoma medication) was 13.2 + 2.4 mm Hg at 12 weeks with a well formed diffuse filtering bleb in all the cases. CONCLUSION: The technique of combining MICS with trabeculectomy and insertion of a foldable IOL through the trabeculectomy fistula is a feasible and valuable technique for cases which require combined cataract and glaucoma surgery

Risk Factors for Tube Shunt Exposure: A Matched Case-Control Study

Purpose. To evaluate potential risk factors for developing tube shunt exposure in glaucoma patients. Patients and Methods. Forty-one cases from 41 patients that had tube shunt exposure from 1996 to 2005 were identified from the Robert Cizik Eye Clinic and Bascom Palmer Eye Institute. Each case was matched with 2 controls of the same gender and with tube shunts implanted within 6 months of the index case. Conditional logistic regression was used to determine risk factors. Results. The study cohort includes a total of 121 eyes from 121 patients. The mean age was 63.6 ± 19.7 years, ranging from 1 to 96 years. The average time to exposure was 19.29 ± 23.75 months (range 0.36–85.74 months). Risk factors associated with tube exposure were Hispanic ethnicity (; OR = 3.6; 95% CI, 1.3–9.7), neovascular glaucoma (; OR = 28.5; 95% CI, 2.6–316.9), previous trabeculectomy (; OR = 5.3; 95% CI, 1.6–17.7), and combined surgery (; OR = 3.7; 95% CI, 1.1–12.7). Conclusions. Hispanic ethnicity, neovascular glaucoma, previous trabeculectomy, and combined surgery were identified as potential risk factors for tube shunt exposure. These potential risk factors should be considered when determining the indication for performing tube shunt implantation and the frequency of long-term followup

Improving the biopharmaceutical attributes of mangiferin using vitamin E-TPGS co-loaded self-assembled phosholipidic nano-mixed micellar systems

The current research work encompasses the development, characterization, and evaluation of self-assembled phospholipidic nano-mixed miceller system (SPNMS) of a poorly soluble BCS Class IV xanthone bioactive, mangiferin (Mgf) functionalized with co-delivery of vitamin E TPGS. Systematic optimization using I-optimal design yielded self-assembled phospholipidic nano-micelles with a particle size of  80% of drug release in 15 min. The cytotoxicity and cellular uptake studies performed using MCF-7 and MDA-MB-231 cell lines demonstrated greater kill and faster cellular uptake. The ex vivo intestinal permeability revealed higher lymphatic uptake, while in situ perfusion and in vivo pharmacokinetic studies indicated nearly 6.6- and 3.0-folds augmentation in permeability and bioavailability of Mgf. In a nutshell, vitamin E functionalized SPNMS of Mgf improved the biopharmaceutical performance of Mgf in rats for enhanced anticancer potency

Biochemical and Ultrastructural Changes in Lens during Aging of Wistar Albino Rats

Aims: To correlate the age-related structural changes in lens with its contents of amino acids and minerals involved in its functional activity (sodium, calcium, magnesium and copper). Study Design: Experimental study. Place and Duration of Study: Department of Zoology, Faculty of Science, Mansoura University, Egypt, between June 2009 and July 2011. Methodology: One hundred male and female albino rats of the Wistar strain (Rattus norvegicus) aging 1, 6, 18, 30 & 42 months were used during experimentation. At the mentioned ages, the animals were sacrificed by diethyl ether and ocular regions were dissected and lens separated. Amino acids content were determined in both lenses of five individuals. In the other five individuals, unilateral ectomized lenses were subjected for chemical determination of calcium, sodium, cupper and magnesium. The rest lenses on the other side were fixed in 10% phosphate buffered formalin followed by 2.5% glutaraldhyde for scanning electron microscopic investigation. Statistically analysis was carried out by the help of SPSS software. Results: The estimated amino acids were altered in both sexes with advancement of aging. The lens amino acids; taurine, prolline, serine, threonine, methionine, lysine and arginine were markedly increased during aging comparing with apparent depletion of asparate, valine and methionine. The alterations in amino acid contents were parallel with increased accumulation of calcium, sodium and cupper and a depletion of magnesium content. Scanning Electron Microscopic (SEM) observations exhibited sequences of changes of the structures of lens fibers and their pattern of attachments during the advancement of aging. In the advanced aged group, the lens fibers become fragile and widely separated as a result of loosely attached of the interfibrillar junctions of the ball and socket especially at 30 & 42 month old rats. Conclusion: Aging led to alterations of lens fibers at ultrastructural levels associated with diversity of changes in their amino acids contents parallel with increase accumulation of sodium, calcium and cupper and a decrease of magnesium content. The observed findings may be attributed to the increase of advanced glycation end products initiated oxidative stress, impairing lens structure and function

Gamma rays-assisted bacterial synthesis of bimetallic silver-selenium nanoparticles: powerful antimicrobial, antibiofilm, antioxidant, and photocatalytic activities

Abstract Background Bimetallic nanoparticles (BNPs) has drawn a lot of attention especially during the last couple of decades. A bimetallic nanoparticle stands for a combination of two different metals that exhibit several new and improved physicochemical properties. Therefore, the green synthesis and design of bimetallic nanoparticles is a field worth exploring. Methods In this study, we present a green synthesis of silver nanoparticles (Ag NPs), selenium (Se) NPs, and bimetallic Ag-Se NPs using Gamma irradiation and utilizing a bacterial filtrate of Bacillus paramycoides. Different Techniques such as UV-Vis., XRD, DLS, SEM, EDX, and HR-TEM, were employed for identifying the synthesized NPs. The antimicrobial and antibiofilm activities of both the Ag/Se monometallic and bimetallic Ag-Se NPs were evaluated against some standard microbial strains including, Aspergillus brasiliensis ATCC16404, Candida albicans ATCC10231, Alternaria alternate EUM108, Fusarium oxysporum EUM37, Escherichia coli ATCC11229, Bacillus cereus ATCC15442, Klebsiella pneumoniae ATCC13883, Bacillus subtilis ATCC15442, and Pseudomonas aeruginosa ATCC6538 as a model tested pathogenic microbes. The individual free radical scavenging potentials of the synthesized Ag NPs, Se NPs, and bimetallic Ag-Se NPs were determined using the DPPH radical scavenging assay. The degradation of methylene blue (MB) dye in the presence of the synthesized Ag NPs, Se NPs, and bimetallic Ag-Se NPs was used to assess their photocatalytic behavior. Results According to the UV-Vis. spectrophotometer, the dose of 20.0 kGy that results in Ag NPs with the highest O.D. = 3.19 at 390 nm is the most effective dose. In a similar vein, the optimal dose for the synthesis of Se NPs was 15.0 kGy dose with O.D. = 1.74 at 460 nm. With a high O.D. of 2.79 at 395 nm, the most potent dose for the formation of bimetallic Ag-Se NPs is 15.0 kGy. The recorded MIC-values for Ag-Se NPs were 62.5 µg mL− 1, and the data clearly demonstrated that C. albicans was the organism that was most susceptible to the three types of NPs. The MIC value was 125 µg mL− 1 for both Ag NPs and Se NPs. In antibiofilm assay, 5 µg mL− 1 Ag-Se NPs inhibited C. albicans with a percentage of 90.88%, E. coli with a percentage of 90.70%, and S. aureus with a percentage of 90.62%. The synthesized NPs can be arranged as follows in decreasing order of antioxidant capacity as an antioxidant result: Ag-Se NPs > Se NPs > Ag NPs. The MB dye degradation in the presence of the synthesized Ag NPs, Se NPs, and bimetallic Ag-Se NPs was confirmed by the decrease in the measured absorbance (at 664 nm) after 20 min of exposure to sunlight. Conclusion Our study provides insight towards the synthesis of bimetallic NPs through green methodologies, to develop synergistic combinatorial antimicrobials with possible applications in the treatment of infectious diseases caused by clinically and industrial relevant drug-resistant strains

Potential antibacterial, antibiofilm, and photocatalytic performance of gamma-irradiated novel nanocomposite for enhanced disinfection applications with an investigated reaction mechanism

Abstract Background Water scarcity is now a global challenge due to the population growth and the limited amount of available potable water. In addition, modern industrialization, and microbial pathogenesis is resulting in water pollution on a large scale. Methods In the present study, reusable Co0.5Ni0.5Fe2O4/SiO2/TiO2 composite matrix was incorporated with CdS NPs to develop an efficient photocatalyst, and antimicrobial agents for wastewater treatment, and disinfection purpose. The antibacterial performance of the gamma-irradiated samples was evaluated against various types of Gram-positive bacteria using ZOI, MIC, antibiofilm, and effect of UV-exposure. Antibacterial reaction mechanism was assessed by bacterial membrane leakage assay, and SEM imaging. In addition, their photocatalytic efficiency was tested against MB cationic dye as a typical water organic pollutant. Results Our results showed that, the formed CdS NPs were uniformly distributed onto the surface of the nanocomposite matrix. While, the resulted CdS-based nanocomposite possessed an average particle size of nearly 90.6 nm. The antibacterial performance of the prepared nanocomposite was significantly increased after activation with gamma and UV irradiations. The improved antibacterial performance was mainly due to the synergistic effect of both TiO2 and CdS NPs; whereas, the highest photocatalytic efficiency of MB removal was exhibited in alkaline media due to the electrostatic attraction between the cationic MB and the negatively-charged samples. In addition, the constructed heterojunction enabled better charge separation and increased the lifetime of the photogenerated charge carriers. Conclusion Our results can pave the way towards the development of efficient photocatalysts for wastewater treatment and promising antibacterial agents for disinfection applications

Nanomaterial-based drug delivery systems as promising carriers for patients with COVID-19

Once the World Health Organization (WHO) declared the COVID-19 outbreak to be pandemic, massive efforts have been launched by researchers around the globe to combat this emerging infectious disease. Here we review the most recent data on the novel SARS-CoV-2 pathogen. We analyzed its etiology, pathogenesis, diagnosis, prevention, and current medications. After that, we summarized the promising drug delivery application of nanomaterial-based systems. Their preparation routes, unique advantages over the traditional drug delivery routes and their toxicity though risk analysis were also covered. We also discussed in detail the mechanism of action for one example of drug-loaded nanomaterial drug delivery systems (Avigan-contained nano-emulsions). This review provides insights about employing nanomaterial-based drug delivery systems for the treatment of COVID-19 to increase the bioavailability of current drugs, reducing their toxicity, and to increase their efficiency