Structure of plasmonic multi spectral Apta sensor and analyzing of bulk and surface sensitivity.

In this work, a multispectral aptasensor structure, including a sub-layer and two side walls, was presented. The cells are positioned at the down and top of the structure, with the down cells oriented perpendicular to the walls and the top cells aligned parallel to the walls. The validity of the findings was verified by the utilization of a numerical simulation technique known as 3D Finite Difference Time Domain (FDTD). The biosensor under consideration exhibits sensitivities of 1093.7 nm/RIU, 754 nm/RIU, and 707.43 nm/RIU in mode III, mode II, and mode I, respectively. In the majority of instances, the quantity of analyte available is insufficient to coat the surface of the sensor thoroughly. Consequently, in this study, the evaluation of surface sensitivity was undertaken alongside bulk sensitivity. The surface sensitivity of the suggested structure for mode II in the sensor layer, with thicknesses of 10, 20, 30, and 70 nm, is measured to be 25, 78, 344, and 717.636 nm/RIU, respectively. Our design incorporates a unique arrangement of sub-layer and side walls, with cells positioned to maximize interaction with the target analyte. This innovative configuration, combined with Ag for its superior plasmonic properties, enables the detection of E. coli O157 with remarkable sensitivity.

Post cataract surgery refractive surprise due to intraocular lens mislabeling.

Key Clinical Message: If an intraocular lens (IOL) is incorrectly labeled, problems can arise for surgeons and patients. Precise biometry is important to accurately determine the IOL power and prevent the implantation of the wrong IOL. Labeling and verifying IOLs with accuracy is crucial to ensuring the best possible results of cataract surgery. Abstract: Mislabeling of IOLs can cause unpredictable problems for surgeons. However, we can prevent incorrect IOLs by using precise biometry to determine accurate IOL power and safely implant the correct IOL. A 50-year-old female with no medical or ocular history came to our clinic complaining of decreased vision in both eyes that had been ongoing for several months. After being diagnosed with cataracts, primary angle closure suspect, and high hyperopia, the patient underwent phacoemulsification surgery. A posterior chamber IOL was implanted, and visco-goniosynechialysis was performed. During follow-up appointments, it was discovered that the patient had an uncorrected visual acuity of 20/50 in her right eye, which was corrected to 20/20 with a + 7.00 D lens. Upon further evaluation, it was determined that the source of the error was due to a manufacturing mislabeling of the IOL power. The patient then underwent successful IOL exchange surgery, and her best-corrected visual acuity became 20/20 with no significant refraction. This case highlights an uncommon source of refractive surprise after phacoemulsification surgery, successfully managed with IOL exchange surgery using the same IOL power from a different brand.

Atypical Central Retinal Artery Occlusion following COVID-19 Infection: A Case Report.

Herein, we report a patient with atypical central retinal artery occlusion (CRAO) following COVID-19 recovery. A 44-year-old male was referred to the emergency room with a history of diplopia and sudden-onset painless visual loss in his left eye. He had a history of 1-week hospitalization for severe COVID-19 infection with pneumonia 3 weeks before, with positive real-time reverse transcription polymerase chain reaction result for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in a nasopharyngeal sample. His visual acuity in the left eye was light perception which became no light perception later. Relative afferent pupillary defect was positive in the left eye. He had anterior chamber and anterior vitreous cells due to spillover and white cotton-wool-like patches in the left eye. He was diagnosed with atypical CRAO with uveitis-like features. After 3 weeks, he developed neovascular glaucoma and was treated with panretinal photocoagulation. In conclusion, SARS-CoV-2-induced vasculopathy and hypercoagulopathy conditions may be involved in the progression of CRAO in our patient. COVID-19 could be a considerable predisposing factor for CRAO.

Enhanced light absorption of organic solar cells based on stopped-trench metal grating.

Here, the influence of dimensional parameters of the trench metal grating on the absorption efficiency of organic solar cells (OSCs) was evaluated. The plasmonic modes were calculated. Due to the capacitance-like charge distribution in a plasmonic configuration, the platform width of grating has a significant influence on the intensity of wedge plasmon polaritons (WPPs) and Gap surface plasmon (GSPs). Stopped-trench gratings would lead to better absorption efficiency than thorough-trenched gratings. The stopped-trench gratings (STG) model with a coating layer showed 77.01% integrated absorption efficiency, which is 19.6% better than previously reported works with 19% less photoactive materials. This model offered 18% integrated absorption efficiency, better than an equivalent planar structure without a coating layer. Specifying the areas with maximum generation on the structure helps us to manage and reduce the thickness and volume of the active layer to control the recombination losses and the cost. We rounded the edges and corners with a curvature radius of 30 nm to investigate tolerance during fabrication. Results demonstrated that the integrated absorption efficiency profile of the blunt model is slightly different from the integrated absorption efficiency profile of the sharp model. Finally, we have studied the wave impedance (Zx) inside the structure. Between the spectrum of λ =∼700 nm to λ=900 nm, an extremely high wave impedance layer was formed. It creates an impedance mismatch between layers and helps us to better trap the incident light ray. STG with a coating layer (STGC) is a promising way to produce OCSs with extremely thin active layers.

Tamoxifen induced maculopathy presenting like macular telangiectasia type 2 in a patient with breast cancer.

INTRODUCTION: Drug-induced crystalline maculopathy has been reported secondary to tamoxifen use for breast cancer treatment. It could be misdiagnosed as macular telangiectasia type 2 (MacTel type 2). CASE REPORT: A 56-year-old woman with a history of diabetes mellitus and breast cancer was referred to our clinic with painless, bilateral, gradual onset of central vision loss for several months. The fundus examination showed the macular pigmentary change in both eyes and a few refractile crystalline deposits in the parafoveal area in the left eye. However, the rest of the retina was normal in both eyes. MANAGEMENT AND OUTCOME: With the diagnosis of tamoxifen-induced maculopathy, the drug was discontinued and supplementary treatment was started. DISCUSSION: In this report, patient medical and drug history was an important and powerful measure. Due to the side effects of long-term use of tamoxifen, we need further studies on the need for retinal screening in these patients.

Minimal Invasive Procedures in Strabismus Surgery: A Narrative Review.

Purpose: To review the principles and different techniques of minimally invasive procedures in strabismus surgery. Methods: This is a narrative review on minimally invasive procedures in strabismus surgery including general aspects and different new modifications on conventional strabismus surgery. We reviewed 24 articles published between 1993 and 2020. Results: Minimal invasive procedures could be categorized into two subsets: one which minimizes conjunctival opening size and another which minimizes the muscle manipulations. Different conjunctival approaches have been introduced, such as Cul-de-sac and minimally invasive strabismus surgery incisions. Furthermore, there are different techniques for extraocular muscle weakening, strengthening, and transposition, such as mini-tenotomy, plication, mini-plication, Nishida, and modified Nishida procedures. Moreover, there are some techniques for handling strabismus in heavy eyes with high myopia and using adjustable sutures for strabismus correction. Conclusions: Minimally invasive procedures in strabismus surgery consist of surgical procedures that minimize tissue disruption, speed up rehabilitation, and often ultimate better outcomes. These techniques could be replaced traditional methods to reduce conjunctival and lid swelling in the direct postoperative period.

Multispectral plasmonic biosensors based on a Penta-supercell metamaterial for detection of prostate-specific antigen: Ultrasensitive in LC resonance mode.

Here, the detection of prostate-specific antigen (PSA) was done using a refractive index sensor based on a plasmonic Penta-supercells metamaterial array. The proposed Penta-supercells metamaterial array consists of four split ring-shaped supercells and a multiplication-shaped supercell in the middle. The results were validated using the three-dimensional Finite-difference time-domain (FDTD) numerical method. The detection of low-concentration biomolecules is a typical drawback of conventional plasmonic biosensors. Our designed Penta-supercells shape biosensor benefits from an ultra-sensitivity. In our designed biosensor, simultaneous excitations of three main plasmon (inductance-capacitance (LC), quadrupole, and dipole) modes can occur, and the LC mode shows a superior sensitivity. The structure was designed optimally, and three different types of metals (Au, Ag, and Al) were examined. LC mode appeiers in Ag and Au and this mode is not seen in Al. Also, the results of this study show the superiority of Ag to Au and Al. Based on the results of this study, the proposed structure achieves a record high sensitivity of 2256 nm/RIU in LC mode and high sensitivity of 1022 nm/RIU in quadrupole mode, and 494 nm/RIU in dipole mode. As another result, the proposed structure is insensitive to orthogonal polarization. The full utilization of these three resonance plasmon modes shows bright prospects for multi-spectral application. In the case of biosensor application, the designed Penta-supercells-based biosensor and its ultra-high sensitivity of 2256 nm/RIU (4.5 times larger than the sensitivity of conventional plasmonic structures) can help the medical to detect low concentrations.

Optic nerve head optical coherence tomography angiography findings in patients with thyroid eye disease: a case-control study.

BACKGROUND: To evaluate changes in the vessel density (VD) of the optic nerve head (ONH) microvasculature in thyroid eye disease (TED) using optical coherence tomography angiography (OCTA). This study aimed to applicate the OCTA as a noninvasive modality in screening TED patients to assess sub-clinical changes. METHODS: In a cross-sectional study, the control group patients were healthy individuals with no ocular abnormalities and were euthyroid. All patients with TED had clinical features of the disease. We divided them into two groups using the clinical activity score (CAS). Patients with CAS scores 0-2 were categorized as group A, and scores three or more as group B. All vessels (AV) and small vessels (SV) VD inside disc and radial peripapillary capillary network were measured using the ONH-OCTA. RESULTS: We evaluated 29 patients with TED and 28 healthy controls. The mean whole image AV VD (mean ± SD: 56.33 ± 2.56, p-value = 0.17) and the mean whole image SV VD (mean ± SD: 49.94 ± 2.56, p-value = 0.16) in the TED group had no statically significant difference compared with the control group (AV mean ± SD: 57.20 ± 20.22, SV mean ± SD: 50.84 ± 2.23). We found a non-significant decrease in AV and SV radial peripapillary capillary VD in the TED group. There was a significant decrease in the mean whole image AV VD (mean ± SD: 54.83 ± 3.07, p-value = 0.005) and the mean whole image SV VD (mean ± SD: 48.60 ± 3.18, p-value = 0.013) in CAS group B compared to group A (AV mean ± SD: 57.45 ± 1.33, SV mean ± SD: 50.95 ± 1.37). CONCLUSION: Our study showed non-significant ONH vascular alterations in patients with TED, including reduced VD of ONH in the radial peripapillary capillary. Patients with higher CAS scores had a more noticeable decrease in ONH microvasculature.

Paracentral Acute Middle Maculopathy and Nonischemic Central Retinal Vein Obstruction in a Young Patient with Protein C Deficiency.

Purpose: To report a case of protein C deficiency with paracentral acute middle maculopathy (PAMM) and nonischemic central retinal vein obstruction (NI-CRVO). Case Report. A previously healthy twenty-one-year-old male was referred with sudden-onset, painless, unilateral paracentral scotomata in the right eye for a week. His uncorrected visual acuity was 20/20 in both eyes. In fundus examination of the right eye, mild venous tortuosity, retinal hemorrhages, and a gray-white opacity in the papillomacular bundle were observed. In the macular spectral-domain optical coherence tomography images, a hyperreflective band was noticed at the level of the inner nuclear layer, indicating PAMM. Fundus appearance and fluorescein angiography findings indicated NI-CRVO diagnosis made. The systemic and laboratory evaluations disclosed a protein C deficiency. Conclusion: In this report, in a healthy young male, combined PAMM and NI-CRVO showed to be the cause of blurred vision in the setting of protein C deficiency.

Changes in Anterior Chamber Parameters Measured by Pentacam in Coronavirus Disease 2019 Infection: A Longitudinal Study.

PURPOSE: To evaluate changes in anterior segment parameters measured by imaging in coronavirus disease 2019 (COVID-19) infection. METHODS: This longitudinal observational study included patients who recovered from COVID-19. All subjects exhibited a confirmed diagnosis of COVID-19 with a positive result of nasopharyngeal reverse transcription-polymerase chain reaction evaluation. Corneal Pentacam (Oculus, Dutenhofen, Germany) imaging was performed at least two weeks after recovery from systemic COVID-19. Measurements were repeated one and three months later. RESULTS: A total of 20 patients, 11 (55%) of whom were females, with a mean age of 35.5 ± 7.1 years (age range: 25-51 years) recovered from nonhospitalized COVID-19 infection, were enrolled in this study. An increase in the keratometry mean front, keratometry mean back, cornea volume, and anterior chamber depth was observed in the longitudinal evaluation; however, they showed no statistical significance. The anterior chamber volume was statistically increased at three-month follow-up, compared to baseline (baseline: 177.8 ± 36.68 mm3; three months: 182.25 ± 39.58 mm3, P=0.048). CONCLUSION: COVID-19 infection may affect the cornea and anterior segment.

Ophthalmic Complications and Managements of Sulfur Mustard Exposure: A Narrative Review.

Sulfur mustard (SM) is a lethal chemical agent that affects many organs, particularly the eyes, respiratory system and skin. Even asymptomatic patients with documented SM vapor exposure may develop organ disorder many years later. Patients with even minor signs in the acute stage may experience late complications that necessitate surgery. Early decontamination and conservative measures could help the patients and decrease the complications. Despite decades of research, there is still no effective treatment for either acute or long-term SM-induced ocular complications. Even after multiple medications and surgical procedures, the majority of patients continue to have symptoms. For dry eye, punctual occlusion, autologous eye drops, and aggressive lubrication are used; for persistent epithelial defects (PED), tarsorrhaphy, amniotic membrane transplant, and stem cell transplantation are used; for total limbal stem cell deficiency (LSCD), living-related conjunctivolimbal allograft and keratolimbal allograft are used; for corneal vascularization, steroids, non-steroidal anti-inflammatory drugs, and anti-vascular endothelial growth factor prescribed; and for corneal opacities, corneal transplantation is done. Platelet rich plasma and topical drops containing stem cell transplantation for LSCD, photodynamic therapy paired with subconjunctival or topical anti-vascular endothelial growth factors for corneal vascularization, topical curcumin and topical ciclosporin-A for dry eye, and orbital fat-derived stem cells for PED are all alternative treatments that can be suggested. Despite the experimental and clinical research on the complications of SM exposure over the past decades, there is still no effective treatment for eye complications. However, supportive medical and surgical management has been applied with relatively good outcome.

Unilateral Acute Central Serous Chorioretinopathy with Inactivated Coronavirus Disease 2019 Vaccination: A Case Report and Review of Literature.

Purpose: To report unilateral acute-onset central serous chorioretinopathy (CSC) following vaccination with inactivated coronavirus disease 2019 (COVID-19) vaccine in a healthy patient. Methods: Case report and review of literature. Results: A 39-year-old male was referred with sudden-onset, painless, unilateral blurred vision in the right eye. His first dose of the Sinopharm vaccine was injected 2 days before. A complete ocular examination revealed central subretinal fluid (SRF) accumulation in favor of CSC in the right eye. Systemic workup disclosed no previous COVID-19 infection or any systemic involvement. After 3 weeks, SRF decreased remarkably without treatment. Conclusions: It is proposed that CSC development can be an ocular adverse effect of COVID-19 vaccination, although it is infrequent. Ophthalmologists should be aware of the possible association between COVID-19 vaccination and ocular adverse effects, but vaccination is the best effectual measure against COVID-19.

Pachychoroid Spectrum Disorder Findings in Patients with Coronavirus Disease 2019.

PURPOSE: To report the occurrence of acute, bilateral, central serous chorioretinopathy (CSC), and pachychoroid spectrum disorder findings in patients with coronavirus disease 2019 (COVID-19). METHODS: In recovered cases of COVID-19 with visual disturbances, complete ocular examinations with multimodal retinal and choroidal evaluation, including enhanced depth imaging optical coherence tomography, fluorescein or indocyanine green angiography, and blue autofluorescence, were obtained. RESULTS: Four COVID-19 recovered patients presented with bilateral blurred vision. Ocular examination and imaging revealed pachychoroid and pachyvessels associated with choroidal hyperpermeability without any obvious intraocular inflammation. Bilateral localized serous retinal detachment was obvious in three cases compatible with pachychoroid associated with CSC manifestation and pachychoroid pigment epitheliopathy in one patient. CSC was resolved with treatment by steroidal antimineralocorticoid (Eplerenone) in two patients and by photodynamic therapy in one patient. None of the patients reported emotional stress and history of corticosteroid consumption. CONCLUSION: Hyperpermeability of the choroid, pachychoroidopathy, or choroidal vessel congestion can be observed or exacerbated in association with COVID-19.

Comparison of pre-hospital triage training by role playing and lecture on nursing students' knowledge, attitude and performance.

Aim: The objective of this study was to determine and compare the effectiveness of two methods of role playing and lecture on knowledge, attitude and performance of nursing' students in the context of pre-hospital triage. Design: This was a pre-test-posttest quasi-experimental study. Methods: A total of 66 nursing students (third year) were assigned to two groups, the control group (N = 23) and intervention group (N = 23). START pre-hospital triage was taught to two groups by using a lecture (control group) and role playing (intervention group) method. Immediately before the intervention and 4 weeks after the training, students' knowledge, attitude and practice in both groups were assessed through a questionnaire and a checklist. Data were analysed using SPSS software version 21. Results: The results showed that the mean scores of knowledge, attitude and performance increased after intervention in both groups (p < .05). The mean (SD) difference of total performance score from baseline to follow-up in the experimental group and the control group was 23.91 (13.83) and 7.00 (13.20), respectively (p < .001). While there was no significant difference between the mean (SD) difference of knowledge and attitude scores in the experimental group and the control group before and after the intervention (p > .05).

Plasmon-enhanced performance of an ultrathin silicon solar cell using metal-semiconductor core-shell hemispherical nanoparticles and metallic back grating.

This paper presents a concept to significantly improve the photocurrent of ultrathin crystalline silicon solar cells using plasmonic hemispherical dielectric-metal (core-shell) nanoparticles and backside gratings. The design of three-dimensional spherical and hemispherical arrays of nanoparticles on top of the surface of 0.8 µm crystalline silicon solar cells was simulated using finite-difference time-domain (FDTD) method. We used the FDTD results to investigate the photocurrent by solving the Poisson and drift diffusion equations. The results indicate an enhancement of between 80% and 93% in the photocurrent for cells with hemispherical Ag and Ag-SiO2 core-shell nanoparticles, respectively, compared to a cell with spherical nanoparticles. In addition, for obtaining a higher photocurrent, triangular gratings were applied on the back side of the absorber and we obtained a photocurrent of 22 mA/cm². The simulated results indicate that the proposed structures increase the spectral response of thin-film crystalline silicon solar cells over a solar spectrum in the range of 400 nm-1200 nm. Finally, we investigated photocurrent as a function of incidence light angle and concluded that this approach is applicable to various thicknesses and shapes of nanoparticles.

Safety evaluation of saffron stigma (Crocus sativus L.) aqueous extract and crocin in patients with schizophrenia.

OBJECTIVES: Saffron is the stigma of Crocus sativus L., which has the potentials to play a role in the treatment of many diseases. Although many researches are now going on this precious spice, there are few data on saffron safety in human, especially in patients with chronic mental illnesses. This study aimed to evaluate the short-term safety and tolerability of both saffron and crocin (its major constituent) in adult patients with schizophrenia. MATERIALS AND METHODS: The capsules of saffron aqueous extract (SAE) and crocin were used to evaluate short-term safety and tolerability in patients with schizophrenia. A double-blind, placebo-controlled study was performed on patients with schizophrenia. The patients were all male and were divided into three 22-patient groups. While receiving their normal treatment, they also received a 12 week treatment with SAE (15 mg twice daily), crocin (15 mg twice daily) or placebo. RESULTS: A total of 61 patients completed the trial; none of them reported a serious side effect. WBC count increased significantly in patients receiving saffron aqua extract (SAE), but it was within the normal range and had no clinical significance. Other hematologic components, markers of thyroid, liver and kidney or inflammation markers had no statistically significant difference among the groups. CONCLUSION: This study showed that SAE and crocin in doses of 15 mg twice daily were safely tolerated in patients with schizophrenia.

How Phytochemicals Prevent Chemical Carcinogens and/or Suppress Tumor Growth?

Phytochemicals are a powerful group of chemicals that are derived from natural resource, especially with plants origin. They have shown to exhibit chemoprevention and chemotherapeutic effects not only in cell lines and in animal models of cancer but also some of them are in the clinical trial phase I and II. Despite numerous reports of these phytochemical effects on cancer, an overview of the mechanisms of their action and their effects on various cellular and molecular functions important in the inhibition of cancer progression has been lacking. In this review, we attempt to catalogue various studies to examine the effect of phytochemicals in cancer initiation, promotion, signaling, and epigenetic changes. Because of the numerous studies in these topics, we only pointed out to some examples in each section.

The attitude of Iranian nurses about do not resuscitate orders.

BACKGROUND: Do not resuscitate (DNR) orders are one of many challenging issues in end of life care. Previous research has not investigated Muslim nurses' attitudes towards DNR orders. AIMS: This study aims to investigate the attitude of Iranian nurses towards DNR orders and determine the role of religious sects in forming attitudes. MATERIALS AND METHODS: In this descriptive-comparative study, 306 nurses from five hospitals affiliated to Tabriz University of Medical Sciences (TUOMS) in East Azerbaijan Province and three hospitals in Kurdistan province participated. Data were gathered by a survey design on attitudes on DNR orders. Data were analyzed using Statistical Package for Social Sciences (SPSS Inc., Chicago, IL) software examining descriptive and inferential statistics. RESULTS: Participants showed their willingness to learn more about DNR orders and highlights the importance of respecting patients and their families in DNR orders. In contrast, in many key items participants reported their negative attitude towards DNR orders. There were statistical differences in two items between the attitude of Shiite and Sunni nurses. CONCLUSIONS: Iranian nurses, regardless of their religious sects, reported negative attitude towards many aspects of DNR orders. It may be possible to change the attitude of Iranian nurses towards DNR through education.