Risk factors and prognosis of pediatric rhegmatogenous retinal detachment in Egypt: a university hospital based study.

AIM: To study and compare the predisposing factors and clinical features of pediatric, adult, and elderly rhegmatogenous retinal detachment (RRD). METHODS: This is an observational analytic cross-sectional study in which patients with RRD admitted for surgery during 6mo period were divided into 3 age groups: pediatric (<18y), adult (18-60y), and elderly (>60y). Patients' demographic data, clinical features, RRD predisposing factors/features including myopia (axial length ≥26.5 mm), aphakia/pseudophakia, blunt trauma, peripheral retinal degenerations, history of RRD in the fellow eye, and surgical interventions/findings were recorded and analyzed. RESULTS: Totally 142 patients (142 eyes) were studied: 26 (18.31%) pediatrics, 86 (60.56%) adults, and 30 (21.13%) elderly. Elderly patients had a significantly higher intraocular pressures and cataracts compared to the other 2 groups (P=0.04). The RRD extent was larger in pediatric group (mostly 4 quadrants) compared to adults and elderly (mostly 2 quadrants), but it was not statistically insignificant (P=0.242). There were not statistically significantly differences in proliferative vitreoretinopathy (PVR) rate, posterior vitreous detachment (PVD) rate, number, site, shape, and size of breaks in three groups. All three groups had macular detachment in all eyes. Myopia and peripheral retinal degenerations were found to be more significant in adults (P=0.049, P=0.035, respectively), while blunt trauma was higher but insignificant in pediatric eyes (P=0.052). Pars plana vitrectomy (PPV) with silicone oil as a tamponade was the most used surgery in all groups. CONCLUSION: There are no significant difference in PVR rate in pediatric eyes but a significant higher rate of total RRD. Blunt trauma is more frequent in pediatrics eyes while myopia and/or peripheral retinal degenerations are more frequent in older ages. The rate of PPV as a choice for surgery is similar among all age groups.

Divisions in a Fibrillar Adhesive Increase the Adhesive Strength.

To realize the potential of bioinspired fibrillar adhesive applications ranging from biomedical devices to robotic grippers, there has been a significant effort to improve their adhesive strength and understanding of the underlying adhesion and detachment mechanisms. These efforts include changes to the backing layer, which connects the roots of all of the pillars in the fibrillar adhesive. However, previous approaches such as thickness or elastic modulus changes are selectively advantageous to the adhesive strength depending on the substrate condition because of the trade-off between conformity to misaligned/rough surfaces and increased interfacial stress concentrations. In this work, we explore mechanical divisions (cuts) in the backing layer as a new approach to improve the adhesive strength without this trade-off. We combine experiments and finite element analysis (FEA) to study the effect of the divisions, which decouples the mechanical interaction between the pillars on the divided layers, and show that the adhesive strength can be improved regardless of the substrate condition. Tensile adhesion experiments show increased adhesive strength with cuts to a micropost array (150 µm diameter posts) by approximately 25% for 4 divisions. In situ imaging of pillar detachment shows a transition of the detachment process from a peel-like detachment to a random detachment sequence. FEA simulations of the detachment process suggest that the increased strength may originate from a simultaneous enhancement of the load distribution between the pillars and the compliance of the backing layer.

Corrosion Resistance of Sulfur-Selenium Alloy Coatings.

Despite decades of research, metallic corrosion remains a long-standing challenge in many engineering applications. Specifically, designing a material that can resist corrosion both in abiotic as well as biotic environments remains elusive. Here a lightweight sulfur-selenium (S-Se) alloy is designed with high stiffness and ductility that can serve as an excellent corrosion-resistant coating with protection efficiency of ≈99.9% for steel in a wide range of diverse environments. S-Se coated mild steel shows a corrosion rate that is 6-7 orders of magnitude lower than bare metal in abiotic (simulated seawater and sodium sulfate solution) and biotic (sulfate-reducing bacterial medium) environments. The coating is strongly adhesive, mechanically robust, and demonstrates excellent damage/deformation recovery properties, which provide the added advantage of significantly reducing the probability of a defect being generated and sustained in the coating, thus improving its longevity. The high corrosion resistance of the alloy is attributed in diverse environments to its semicrystalline, nonporous, antimicrobial, and viscoelastic nature with superior mechanical performance, enabling it to successfully block a variety of diffusing species.

Graphene fatigue through van der Waals interactions.

Graphene is often in contact with other materials through weak van der Waals (vdW) interactions. Of particular interest is the graphene-polymer interface, which is constantly subjected to dynamic loading in applications, including flexible electronics and multifunctional coatings. Through in situ cyclic loading, we directly observed interfacial fatigue propagation at the graphene-polymer interface, which was revealed to satisfy a modified Paris' law. Furthermore, cyclic loading through vdW contact was able to cause fatigue fracture of even pristine graphene through a combined in-plane shear and out-of-plane tear mechanism. Shear fracture was found to mainly initiate at the fold junctions induced by cyclic loading and propagate parallel to the loading direction. Fracture mechanics analysis was conducted to explain the kinetics of an exotic self-tearing behavior of graphene during cyclic loading. This work offers mechanistic insights into the dynamic reliability of graphene and graphene-polymer interface, which could facilitate the durable design of graphene-based structures.

Efficacy of non-fovea-sparing ILM peeling for symptomatic myopic foveoschisis with and without macular hole.

AIM: To study anatomical and visual outcomes of pars plana vitrectomy (PPV) with non-fovea-sparing (entire) internal limiting membrane (ILM) peeling in eyes with myopic foveoschisis (MF). METHODS: Prospective interventional case series of eyes undergoing PPV with entire ILM peeling for symptomatic MF. MAIN OUTCOME MEASURES: Preoperative spectral domain optical coherence tomography (SD-OCT) epiretinal membrane, anomalous posterior vitreous detachment, vitreoschisis and postoperative changes in SD-OCT central foveal thickness (CFT), ellipsoid zone defect, foveal detachment (FD), macular hole (MH) diameter (if present) and best-corrected visual acuity (BCVA) in logarithm of the minimum angle of resolution (logMAR). RESULTS: This study included 21 eyes (21 patients) with mean age 60.4±13.1, 15 females (71.4%). All patients achieved complete postoperative reattachment by SD-OCT (no FD) 6 months post vitrectomy, with no iatrogenic intraoperative or postoperative MH, and with significant improvement in final BCVA from 1.6±0.30 to1.0±0.2 logMAR, and in CFT from 918.2±311.4 to182.3±33.1 µm. Patients were subdivided into subgroup A: 11 eyes without MH; and subgroup B: 10 eyes with MH, the latter had significant improvement in MH diameter (p=0.005). Preoperative BCVA was a significant risk factor for visual gain, while preoperative FD and CFT were significant for CFT change. CONCLUSION: Vitrectomy with non-fovea-sparing (entire) ILM peeling resulted in a significant functional and anatomical improvement in eyes with MF with/without MH with no reported complications. Results are comparable to fovea-sparing ILM peeling.

Functional and structural outcomes of ILM peeling in uncomplicated macula-off RRD using microperimetry & en-face OCT.

PURPOSE: To investigate functional and structural outcomes of internal limiting membrane (ILM) peeling during primary vitrectomy for uncomplicated macula-off rhegmatogenous retinal detachment (RRD). METHODS: In this prospective interventional randomized comparative study, 43 eyes (43 patients) were randomly divided into group A (20), and group B (23), with and without ILM peeling respectively. Patients were evaluated clinically, and by spectral-domain optical coherence tomography (SD-OCT) and microperimetry (MP) following silicone oil removal. Main outcome measures were functional-MP (mean and foveal retinal sensitivity; MRS, FRS) and best-corrected visual acuity (BCVA)-and anatomical-en-face image analysis (retinal dimples), and SD-OCT changes [epiretinal membrane (ERM), subretinal fluid (SRF), ellipsoid zone disruption, central subfoveal thickness (CSFT), and foveal contour]. RESULTS: All eyes achieved complete postoperative attachment with mean BCVA 1.0 ± 0.4 logMAR (6/60) in group A, and 0.4 ± 0.4 logMAR (6/15) in group B (p < 0.001). MRS and FRS were significantly higher in group B (p = 0.037 and 0.036 respectively). En-face OCT showed retinal dimples in all patients in group A (29.17 ± 7.67 dimples), compared to none in group B (p = 0.007). ERM did not develop in any eye in group A, while it developed in 17.4% of eyes in group B (p = 0.05). CONCLUSION: Although ILM peeling prevented ERM, it resulted in poorer visual outcome in these uncomplicated RRD cases, and might be better reserved only for complicated cases.

Why Poor Vision Despite an Attached Retina following Primary Vitrectomy in Egyptian Patients?

OBJECTIVE: To correlate findings on spectral domain optical coherence tomography (SD-OCT) and best-corrected visual acuity (BCVA) following primary vitrectomy for rhegmatogenous retinal detachment (RRD). METHODS: In this prospective, interventional, non-randomized case series, 71 eyes with RRD of intermediate severity underwent primary vitrectomy followed by SD-OCT one month later. Main outcome measures were inner segment/outer segment (IS/OS) junction line and external limiting membrane (ELM) disruption. RESULTS: All patients achieved reattachment with mean BCVA of 0.77 ± 0.36 logMAR. There was statistically significant correlation between each length of IS/OS and ELM defect on the one hand, and BCVA on the other hand. CONCLUSION: The extent of IS/OS and ELM disruption explains the poor visual outcome in successful RD surgery with an otherwise normal foveal contour.

Comparison Between Sublingual and Vaginal Administration of Misoprostol in Management of Missed Abortion.

AIM: The aim of the present study is to compare between sublingual administration of misoprostol and vaginal administration in the management of missed abortion. MATERIALS AND METHODS: The study was conducted in El-Shatby Maternity Hospital on 160 patients diagnosed as missed abortion by ultrasonographic examination. Cases were divided into two groups according to the methods of misoprostol administration, whether sublingual or vaginal. Patients of the two groups were observed for the times of uterine colic starting, cervical dilation, and conceptus expulsion, along with recording of any side effects. RESULT: During the follow-up of our cases we found that sublingual route is more effective than vaginal route in the management of missed abortion. The difference between the two groups in percentage of conceptus expulsion was statistically significant. The most common side effects were nausea which was present in 55 % of cases in group I (sublingual) and in 40 % of cases in group II (vaginal) then severe pain in 25 % of cases in group I (sublingual) and in 20 % of cases in group II (vaginal) and hyperpyrexia in 15 % of cases in group I (sublingual) and in 5 % of cases in group II (vaginal). CONCLUSION: Sublingual administration of misoprostol is more effective than its vaginal administration in missed abortion management. Side effect of misoprostol as nausea, vomiting, fever is more common with sublingual administration in comparison with its vaginal administration.

New nitrogenous compounds from a Red Sea sponge from the Gulf of Aqaba.

Chemical investigation of an unknown marine sponge, which was collected in the Gulf of Aqaba (Jordan), afforded a new brominated alkaloid 3-amino-1-(2-amino-4-bromophenyl)propan-1-one (1), as well as 7-bromoquinolin-4(1H)-one (2) which had previously only been reported as a synthetic compound. In addition, caulerpin (6), previously only known to be produced by algae, was likewise isolated. Furthermore, three known alkaloids including (Z)-5-(4-hydroxybenzylidene)-hydantoin, (Z)-6-bromo-3'-deimino-2',4'-bis(demethyl)-3'-oxoaplysinopsin, and 6-bromoindole-3-carbaldehyde (3-5), were also obtained. All compounds were unambiguously elucidated based on extensive 1D and 2D NMR spectroscopy, LCMS, as well as by comparison with the literature and tested for their cytotoxic activity toward the mouse lymphoma cell line L5178Y.

Cardiac catheterisation in nonagenarians: Single center experience.

OBJECTIVE: To explore the treatment, procedure related risks, and outcomes of patients older than 90 years of age undergoing cardiac catheterization. METHODS: We retrospectively studied 32 patients ≥ 90 years (93.0 ± 1.2 years) who underwent cardiac catheterisation in a tertiary specialist hospital (0.2% of 14,892 procedures during three years). The results were compared to a patient cohort younger than 90 years of age. RESULTS: Baseline characteristics revealed a higher prevalence of diabetes (P < 0.001), chronic obstructive pulmonary disease (P < 0.04), previous myocardial infarction (P < 0.02), and complex coronary anatomy (SYNTAX score 33 vs. 19) in nonagenarians. Patients < 90 years of age showed more hyperlipidemia (P < 0.01) and previous percutaneous coronary interventions (P < 0.015). Nonagenarians underwent coronary angiography more often for acute coronary syndrome (ACS) (P < 0.003), were presented more often in cardiogenic shock (P < 0.003), and were transferred faster to coronary angiography in cases of ACS (P < 0.0001). The observed in-hospital mortality rate (13% study group vs. 1% control group; P < 0.003) in nonagenarians was lower than the calculated rate of thrombolysis in myocardial infarction (TIMI) and global registry of acute cardiac events (GRACE) mortality and strongly influenced by the severity of clinical presentation and the presence of co-morbidities. CONCLUSION: Despite the common scepticism that cardiac catheterisation exposes patients ≥ 90 years to an unwarranted risk, our data demonstrate an acceptable incidence of complications and mortality in this group of patients.

External and intestinal parasites of pet dogs with reference to zoonotic toxocariasis.

Examination of 3000 pet dogs over two years at the Veterinary Teaching Hospital, Faculty of Veterinary Medicine revealed external and internal parasites. The external parasites were Rhipicephalus sanguineus, Ctenocephalus felis, Sarcoptes canis, and Sarcoptes scabiei. The internal parasites were Echinococcus granulosus, Dipylidium caninum, rare Heterophyes heterophyes, and Toxocara canis. Toxocara eggs were detected in 9.83%. The results were discussed with reference to zoonotic toxocariasis.

ELISA-seroprevalence of Toxoplasma gondii in draught horses in Greater Cairo, Egypt.

Toxoplasma gondii is one of the important zoonotic parasites of worldwide. In this paper the seroprevalence of T. gondii in draught horses (3-15 years) including 90 males and 10 females in the first half of the year 2009 was studied. The result showed that the overall ELISA-T. gondii antibodies were 25% of the horses in Greater Cairo, 50% (females) and 22.2% (males).

Efficacy of temperature, and two commonly used molluscicides and fertilizers on Fasciola gigantica eggs.

This study evaluated the effect of temperature, molluscicides (Copper sulphate and Niclosamide), fertilizers (Superphosphate and Ammonium sulphate) on the hatchability of Fasciola gigantica eggs. The results showed that hatchability decreased to 4% when eggs were incubated in bile secretion at 37 degrees C for 5 days and to 1.4% for 10 days, but few eggs incubated in water at 37 degrees C hatched. Bile secretion at 37 degrees C was a poor medium for in-vitro egg preservation. But, hatching occurred only when eggs were transferred to water at 26 degrees C. Temperature fluctuation from 26-4 degrees C or from 32-4 degrees C had an inhibitory effect on embryos development (35.2% & 32.3%, respectively) as compared to controls (60% & 63.9%, respectively). The incubation period (19 & 17 days) was higher than controls (14 & 12 days, respectively). The LC50 & LC90 of Copper sulphate and Niclosamide against Biomphalaria alexandrina and Lymnaea natalenesis had no toxic effect on Fasciola eggs. The higher concentrations of Copper sulphate (30 ppm) and Niclosamide (1 ppm) slightly lower eggs hatchability rate than controls. The rate decreased by increasing the exposure time from 3 to 6 hours with both molluscicides. Ammonium sulphate had a lethal effect on eggs, but Superphosphate had some inhibitory effect on egg development, which increased by increasing Superphosphate concentration or with the prolongation of the exposure time.

The diagnostic efficacy of Fasciola gigantica coproantigen in naturally infected cattle and buffaloes.

Monoclonal antibody sandwich ELISA was used detect F. gigantica coproantigen in 33 selected animals according to the faecal history to evaluate sensitivity and specificity by using three different rabbit hyper-immune sera; Copro HIS, Egg HIS and ES HIS. The results showed that Copro HIS & ES HIS detected F. gigantica coproantigen in faecal of naturally infected cattle and buffaloes, but egg HIS failed. The 26-28 KDa coproantigen proved sensitivity (81.8%) and specificity (90.9%) in diagnosis of fascioliasis. Also, there was a positive statistical significance between number of F. gigantica egg per gm faeces (EPG) and mean sandwich ELISA OD. values for copro-antigen. For diagnostic value of F. gigantica coproantigen in comparison with ES antigen, EITB was done on field sera of cattle and buffaloes of known faecal history. The F. gigantica coproantigen bands of 27.6 & 72.1 KDa were specific for diagnosis animal fascioliasis, but the 72.1 KDa was less sensitive than the 27.6 KDs. The immunoblotting reaction was more intensive the with fractionated ES antigen than with fractionated coproantigen.

Efficacy of some Fasciola gigantica antigens.

The present study tested the antigenic relationship between the three Egyptian strain of Fasciola gigantica antigens; coproantigen, excretory-secretory and egg antigens, versus their related hyper-immune sera and select the most specific one. By using SDS-PAGE, a structural homology was demonstrated in F. gigantica ES and egg antigens. This homology was resided in the components of the similar molecular weights between both antigens. When no cross-reaction was recorded with the coproantigen, the intense cross-reaction occurred between ES and egg antigens in ELISA technique. This was attributed to the presence of common bands at 18.0, 20.4 and 27.6 KDa in between them. Consequently, the F. gigantica coproantigen and Copro HIS reflected the lowest level of the cross-reaction with the other evaluated F. gigantica antigens. The cross-reaction elucidated in the present study between the F. gigantica ES and egg antigens was mainly at the low serum dilutions. The distinction between the specific and the cross-reactive binding activities was clear ly marked with the highly diluted sera.

Zoonotic hydatidosis in donkeys: post mortum examination in the Zoo, Giza, Egypt.

A total of 17 out of 160 donkeys slaughtered had hepatic hydatidosis as proved macroscopically and microscopically. The epidemiology of zoonotic echinococcosis/hydatidosis was reviewed and discussed.

HLA alleles in Egyptian HCV genotype-4 carriers.

Risk factors affecting asymptomatic HCV carriers as well as intrafamilial HCV transmission are not completely known. We hypothesized that immunological factors related to HLA profiles may affect the intrafamilial transmission. We investigated the possible association between HLA class I & II genes and the presence of HCV infection, as well as their possible role in intrafamilial tramsmition. One hundred forty five individuals comprising 40 families were recruited from bone marrow transplantation (BMT) unit at the National Cancer Institute, Cairo University. Serologic class I and generic class II MHC alleles were determined. Hepatitis C virus was detected by enzyme immunoassay (EIA) and confirmed by INNO-LIA. Detection of viral RNA was also confirmed by RT-PCR and HCV genotyping was done by immunoblotting (INNO-LiPA) and direct sequencing by TrueGene kit. Out of the 145 serum samples, 33 were positive for HCV antibodies by EIA and confirmed by both immunoblotting techniques and RT-PCR. Twenty-eight of them were eligible for HCV typing. The genotypes detected were 4, 2a, 1a and 1b. A mixed infection by more than one genotype was detected in 9 cases. Six families had 2 or more members reactive for HCV antibodies. Intrafamilial transmission was confirmed by HCV-sequence in 3 families. HLA class I & II alleles A28, A29, B14 & DR7 were significantly encountered in HCV positive than negative cases (p=0.040, 0.003, 0.001 & 0.010 respectively). In addition, two cases showed evidence of viral clearance, both expressed B50 (21) allele. We conclude that, there is a possible impact of both class I and class II alleles on HCV infection, resistance, clearance and intrafamilial transmission.